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You searched for: Publication year rev 7985-2015 Remove constraint Publication year rev: 7985-2015 Subject term dioxane Remove constraint Subject term: dioxane
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1. A biomimetic 3D microtubule-orientated poly(lactide-co-glycolide) scaffold with interconnected pores for tissue engineering

Author:
Hong Shen; Yuguang Niu; Xixue Hu; Fei Yang; Shenguo Wang; Decheng Wu
Source:
Journal of materials chemistry B 2015 v.3 no.21 pp. 4417-4425
ISSN:
2050-7518
Subject:
benzene; bioactive properties; biomimetics; cell culture; chemistry; dioxane; extracellular matrix; fibroblast growth factor 2; freezing point; microtubules; myocytes; porosity; rabbits; separation; smooth muscle; solvents; tissue engineering; viability
Abstract:
... An ideal tissue engineering scaffold should imitate physical and biochemical cues of natural extracellular matrix and have interconnected porous structures with high porosity to provide adequate space for cell seeding, growth and proliferation, as well as nutrient delivery and metabolized product elimination. In this study, we examined the feasibility of fabricating microtubule-orientated poly(lac ...
DOI:
10.1039/c5tb00167f

2. A chiral phosphoric acid catalyst for asymmetric construction of 1,3-dioxanes

Author:
Akira Matsumoto; Keisuke Asano; Seijiro Matsubara
Source:
Chemical communications 2015 v.51 no.58 pp. 11693-11696
ISSN:
1364-548X
Subject:
catalysts; chemical reactions; dioxane; enantioselectivity; phosphoric acid; polyketides
Abstract:
... A novel method of enantioselective 1,3-dioxane construction via a hemiacetalization/intramolecular oxy-Michael addition cascade by a chiral phosphoric acid catalyst was developed. The product was successfully transformed into an optically active 1,3-polyol motif, indicating that the proposed reaction can provide useful chiral building blocks for the de novo synthesis of polyketides. ...
DOI:
10.1039/c5cc04124d

3. A novel transformation of β-1,2,3-thiadiazol-5-yl enamines into thieno[2,3-d]pyridazines

Author:
Yuri Rozin; Sergey Zhidovinov; Tetyana Beryozkina; Yuri Shafran; Gert Lubec; Oleg Eltsov; Pavel Slepukhin; Uwe Knippschild; Joachim Bischof; Wim Dehaen; Vasiliy Bakulev
Source:
Tetrahedron letters 2015 v.56 no.12 pp. 1545-1547
ISSN:
0040-4039
Subject:
carboxylic acids; chemical bonding; chemical reactions; chemical structure; dioxane; enamines; organochlorine compounds; pyridazines; secondary amines; temperature
Abstract:
... Reactions of β-1,2,3-thiadiazol-5-yl enamines with acetyl chloride in 1,4-dioxane lead to the formation of either dienamines or novel thieno[2,3-d]pyridazines depending on the time and reaction temperature. Conditions were found for the selective synthesis of thieno[2,3-d]pyridazines. A plausible mechanism involves formation of C–S and C–C bonds and a novel ring rearrangement of 5-vinyl-1,2,3-thia ...
DOI:
10.1016/j.tetlet.2015.02.013

4. A triazine-based porous organic polymer: a novel heterogeneous basic organocatalyst for facile one-pot synthesis of 2-amino-4H-chromenes

Author:
Sudipta K. Kundu; Asim Bhaumik
Source:
RSC advances 2015 v.5 no.41 pp. 32730-32739
ISSN:
2046-2069
Subject:
2-naphthol; X-ray diffraction; aldehydes; carbon; catalytic activity; condensation reactions; cyanuric chloride; differential thermal analysis; dioxane; moieties; nitrogen; nuclear magnetic resonance spectroscopy; organocatalysts; polymers; resorcinol; scanning electron microscopy; sorption; stable isotopes; synthesis; thermogravimetry; transmission electron microscopy
Abstract:
... A new triazine-based porous organic polymer TPOP-2 has been synthesized through the reaction between cyanuric chloride and tris(2-aminoethyl)amine in anhydrous 1,4-dioxane under N₂ atmosphere. The porous polymer has been characterized by powder X-ray diffraction, N₂ sorption, HR TEM, FE SEM, ¹³C CPMAS NMR, CO₂-TPD, TG-DTA and FT IR spectroscopic tools. Due to the high density of amine and triazine ...
DOI:
10.1039/c5ra00951k

5. An optical-fiber sensor based on time-gated fluorescence for detecting water content in organic solvents

Author:
Dawei Huang; Yongxin Bing; Hao Yi; Wei Hong; Cui Lai; Qingwei Guo; Chenggang Niu
Source:
Analytical methods 2015 v.7 no.11 pp. 4621-4628
ISSN:
1759-9679
Subject:
acetonitrile; acrylamides; analytical methods; detection limit; dioxane; ethanol; europium; fluorescence; fluorescent dyes; glass; optical fibers; solvents; triethylene glycol; water content
Abstract:
... In this paper, the authors proposed an optical-fiber sensor based on time-gated fluorescence with high sensitivity for water content determination in organic solvents, and a type of europium ion fluorescent chelate (EIFC) with a long fluorescence lifetime was synthesized and used as the fluorescent indicator. Covalent immobilization was used to solve the problem caused by the leakage of fluorescen ...
DOI:
10.1039/c5ay00110b

6. Application of polymeric macroporous supports for temperature-responsive chromatography of pharmaceuticals

Author:
Alexandros Lamprou; Agni-Faviola-Mika Gavriilidou; Giuseppe Storti; Miroslav Soos; Massimo Morbidelli
Source:
Journal of chromatography 2015 v.1407 pp. 90-99
ISSN:
0021-9673
Subject:
binding capacity; brushes; chromatography; dioxane; drugs; gelation; hydrophobic bonding; hydrophobicity; mass transfer; methanol; monoclonal antibodies; pH; packaging materials; peptides; polymers; porous media; proteins; sodium chloride; solvents; statistical analysis; temperature
Abstract:
... A macroporous particulate support prepared previously by reactive gelation under shear and functionalized with poly(N-isopropylacrylamide), PNIPAM, brushes of variable length is applied for temperature-responsive chromatography, whereby temperature modulates hydrophobic interactions. Several different analytes, including small pharmaceuticals, peptides, proteins and monoclonal antibodies are emplo ...
DOI:
10.1016/j.chroma.2015.06.028

7. Aromatic evolution of wine packed in virgin and recycled PET bottles

Author:
Clara Dombre; Peggy Rigou; Jérémie Wirth; Pascale Chalier
Source:
Food chemistry 2015 v.176 pp. 376-387
ISSN:
0308-8146
Subject:
alcohols; bottles; dioxane; esters; flavor; furfural; glass; odor compounds; oxygen; permeability; pyruvic acid; sorption; wines
Abstract:
... The evolution of the aromatic profile of a rosé wine packed in glass, virgin and recycled PET bottles was studied. Wine stored in PET and glass bottles was clearly differentiated after 5months of storage but only by a limited number of compounds. More pronounced decrease of oxygen sensitive compounds such as methionol was observed in PET bottles as well as the apparition of oxidative and ageing ar ...
DOI:
10.1016/j.foodchem.2014.12.074

8. Bio-based PBS copolyesters derived from a bicyclic d-glucitol

Author:
Elena Zakharova; Abdelilah Alla; Antxon Martínez de Ilarduya; Sebastián Muñoz-Guerra
Source:
RSC advances 2015 v.5 no.57 pp. 46395-46404
ISSN:
2046-2069
Subject:
biodegradability; condensation reactions; crystal structure; dioxane; glass transition temperature; glycols; hydrolysis; melting; melting point; microstructure; molecular weight; polybutylene succinate; polyesters; sorbitol; thermal stability
Abstract:
... 2,4:3,5-di-O-methylene-d-glucitol (Glux-diol) was used for the synthesis of poly(butylene succinate) (PBS) copolyesters by melt polycondensation. Glux-diol possess a rigid bicyclic asymmetric structure made of two fused 1,3-dioxane rings and two hydroxyl functions at the end positions. Copolyesters were prepared over the whole range of compositions with molecular weights varying from 26 000 to 46  ...
DOI:
10.1039/c5ra03844h

9. Bio-based solvents for the Baylis–Hillman reaction of HMF

Author:
Jia-Neng Tan; Mohammed Ahmar; Yves Queneau
Source:
RSC advances 2015 v.5 no.85 pp. 69238-69242
ISSN:
2046-2069
Subject:
dioxane; ethanol; hydroxymethylfurfural; isopropyl alcohol; solvents
Abstract:
... The Baylis–Hillman reaction of HMF was investigated in various bio-based solvent systems and in water. Although pure water is able to promote the reaction, aqueous mixtures with ethanol, isopropanol, methyl-THF (MeTHF), tetrahydrofurfuryl-alcohol (THFA) show better overall efficacy for the HMF Baylis–Hillman reaction than pure water or the pure bio-based solvent. Such solvent systems can replace T ...
DOI:
10.1039/c5ra14554f

10. Catalytic behaviour of TiO₂–ZrO₂ binary oxide synthesized by sol–gel process for glucose conversion to 5-hydroxymethylfurfural

Author:
Luqman Atanda; Adib Silahua; Swathi Mukundan; Abhijit Shrotri; Gilberto Torres-Torres; Jorge Beltramini
Source:
RSC advances 2015 v.5 no.98 pp. 80346-80352
ISSN:
2046-2069
Subject:
catalysts; catalytic activity; dioxane; glucose; hydroxymethylfurfural; oxides; polymers; sol-gel processing; solvents
Abstract:
... The catalytic application of as-synthesized TiO₂–ZrO₂ binary oxides was examined for the conversion of glucose to produce 5-hydroxymethylfurfural (HMF). Highest HMF yield (74%) at glucose concentration of 5 wt% was obtained with TiO₂–ZrO₂ (1/1) and Amberlyst 70 catalyst system in a water–THF biphasic reaction system. Notably, a much higher HMF yield (86%) was achieved when the organic phase of the ...
DOI:
10.1039/c5ra15739k

11. Cyclopentyl methyl ether–NH₄X: a novel solvent/catalyst system for low impact acetalization reactions

Author:
Ugo Azzena; Massimo Carraro; Ashenafi Damtew Mamuye; Irene Murgia; Luisa Pisano; Giuseppe Zedde
Source:
Green chemistry 2015 v.17 no.6 pp. 3281-3284
ISSN:
1463-9270
Subject:
aldehydes; ammonium salts; catalysts; dioxane; green chemistry; ketones; methyl ethers; solvents
Abstract:
... Cyclopentyl methyl ether, a low impact ether forming a positive azeotrope with water, was successfully employed as a solvent in the synthesis of 1,3-dioxanes and 1,3-dioxolanes carried out under Dean-Stark conditions by the acetalization of aliphatic and aromatic aldehydes or ketones, employing ammonium salts as environmentally friendly acidic catalysts. ...
DOI:
10.1039/c5gc00465a

12. Development and validation of thin layer chromatography method for simultaneous determination of seven chlorophenoxy and benzoic acid herbicides in water

Author:
Z. S. Kavrakovski; V. Gj. Rafajlovska
Source:
Journal of analytical chemistry 2015 v.70 no.8 pp. 995-1000
ISSN:
1061-9348
Subject:
2,4,5-T; 2,4-D; MCPA (herbicide); MCPB (herbicide); acetic acid; aluminum; benzene; benzoic acid; correlation; densitometry; detection limit; dicamba; dioxane; groundwater; silica gel; thin layer chromatography
Abstract:
... Thin layer chromatography (TLC) densitometric method for simultaneous determination of seven chlorophenoxy and benzoic acid herbicides (2,4-D; 2,4,5-T; MCPA; 2,4-DP; MCPP; Dicamba and MCPB) in water samples was developed and validated. A mobile phase consisted of benzene−dioxane−glacial acetic acid in ratio of 45: 10: 2 and TLC silica gel 60 F₂₅₄ aluminium plate were used. Detection was carried ou ...
DOI:
10.1134/S1061934815080122

13. Diastereoselective Synthesis of Protected 1,3-Diols by Catalytic Diol Relocation

Author:
Goodwin Justin A.; Ballesteros Carl F.; Aponick Aaron
Source:
Organic letters 2015 v.17 no.22 pp. 5574-5577
ISSN:
1523-7052
Subject:
bismuth; chemical reactions; chemical structure; diastereoselective synthesis; diastereoselectivity; dioxane; glycols; gold
Abstract:
... A complementary diastereoselective gold(I) or bismuth(III) catalyzed tandem hemiacetalization/dehydrative cyclization of 1,5-monoallylic diols was developed to access 1,3-dioxolanes and dioxanes. This methodology provides rapid access to protected 1,3-diols under mild conditions with high levels of diastereoselectivity. ...
DOI:
10.1021/acs.orglett.5b02725

14. Dimeric resorcinarene salt capsules with very tight encapsulation of anions and guest molecules

Author:
Fangfang Pan; N. Kodiah Beyeh; Kari Rissanen
Source:
RSC advances 2015 v.5 no.71 pp. 57912-57916
ISSN:
2046-2069
Subject:
ammonium; anions; crystallization; dioxane; encapsulation; methanol; trapping
Abstract:
... Crystallization of N-cyclohexyl ammonium resorcinarene triflate from methanol results in a dimeric capsule capable of trapping two triflate anions and two methanol molecules within a 341 ų cavity while with 1,4-dioxane as a guest it forms a new larger dimeric capsule with volume of 679 ų encapsulating four 1,4-dioxane and four water molecules, resulting in packing coefficients of 0.75 and 0.67, ...
DOI:
10.1039/c5ra11905g

15. Direct conversion of carbohydrates to γ-valerolactone facilitated by a solvent effect

Author:
Jinglei Cui; Jingjing Tan; Tiansheng Deng; Xiaojing Cui; Hongyan Zheng; Yulei Zhu; Yongwang Li
Source:
Green chemistry 2015 v.17 no.5 pp. 3084-3089
ISSN:
1463-9270
Subject:
catalysts; cellulose; dioxane; ethanol; fructose; glucose; green chemistry; inulin; lactones; maltose; methanol; recycling; ruthenium; solvents; starch; sucrose; titanium dioxide
Abstract:
... The carbohydrates (cellulose, starch, inulin, maltose, sucrose, glucose and fructose) were converted efficiently into γ-valerolactone (GVL) over combined H₃PW₁₂O₄₀ and Ru/TiO₂ catalysts under mild conditions. The basicity of oxygen-containing solvents had a remarkable effect on the acid strength of H₃PW₁₂O₄₀, which resulted in great variation in the yield of GVL. H₃PW₁₂O₄₀ was more effective in 20 ...
DOI:
10.1039/c5gc00110b

16. Dynamics and Mechanism of UV-Damaged DNA Repair in Indole–Thymine Dimer Adduct: Molecular Origin of Low Repair Quantum Efficiency

Author:
Guo Xunmin; Liu Zheyun; Song Qinhua; Wang Lijuan; Zhong Dongping
Source:
Journal of physical chemistry 2015 v.119 no.8 pp. 3446-3455
ISSN:
1520-5207
Subject:
DNA; DNA repair; acetonitrile; biomimetics; dioxane; electron transfer; models; physical chemistry; solvents
Abstract:
... Many biomimetic chemical systems for repair of UV-damaged DNA showed very low repair efficiency, and the molecular origin is still unknown. Here, we report our systematic characterization of the repair dynamics of a model compound of indole–thymine dimer adduct in three solvents with different polarity. By resolving all elementary steps including three electron-transfer processes and two bond-brea ...
DOI:
10.1021/jp512413t

17. Effect of complete dissolution in LiCl/DMSO on the isolation and characteristics of lignin from wheat straw internode

Author:
Feng Gu; Wenjuan Wu; Zhiguo Wang; Toyoma Yokoyama; Yongcan Jin; Yuji Matsumoto
Source:
Industrial crops and products 2015 v.74 pp. 703-711
ISSN:
0926-6690
Subject:
carbohydrates; chemistry; dimethyl sulfoxide; dioxane; enzymatic hydrolysis; lignin; lithium chloride; milling; nuclear magnetic resonance spectroscopy; wheat straw
Abstract:
... A modified cellulolytic enzyme lignin (CEL) protocol, named regeneration cellulolytic enzyme lignin (RCEL), was developed for the enhancement of carbohydrate removal and lignin extraction with short ball milling hours. The process of complete dissolution in lithium chloride/dimethyl sulfoxide (LiCl/DMSO) and regeneration in water prior to enzymatic hydrolysis were applied for improving the isolati ...
DOI:
10.1016/j.indcrop.2015.06.002

18. Enhanced Emission of Polyethyleneimine-Coated Copper Nanoclusters and Their Solvent Effect

Author:
Ling Yu; Wu Jing Jing; Gao Zhong Feng; Li Nian Bing; Luo Hong Qun
Source:
The Journal of Physical Chemistry C 2015 v.119 no.48 pp. 27173-27177
ISSN:
1932-7455
Subject:
acetonitrile; color; copper; dimethyl sulfoxide; dioxane; ethylene glycol; fluorescence; nanoparticles; nanosilver; physical chemistry; polyethyleneimine; silver; solvents; spectral analysis; tetrahydrofuran
Abstract:
... The solvent-dependent properties of polyethyleneimine (PEI)-capped Cu nanoclusters are discussed in this study. The PEI-encapsulated Cu nanoclusters were dispersed in 12 polar organic solvents, and in water and alcohols, the nanoclusters display similar properties and could be stable in the dark. Moreover, Cu nanoclusters exhibit a blue shift of the emission peak in tetrahydrofuran (THF) and 1,4-d ...
DOI:
10.1021/acs.jpcc.5b09488

19. Evaluating effects of benzene–ethanol extraction on molecular weight of lignin isolated from pretreated bamboo substrate

Author:
Xiaojuan Ma; Xin Zheng; Ling Lin; Lihui Chen; Shrikant Survase; Liulian Huang; Shilin Cao
Source:
Wood science and technology 2015 v.49 no.5 pp. 945-955
ISSN:
0043-7719
Subject:
Fourier transform infrared spectroscopy; bamboos; dioxane; hydrolysis; lignin; molecular weight; nuclear magnetic resonance spectroscopy; solubility
Abstract:
... In a previous study by the authors, it was found that benzene–ethanol extraction (BAE) could remove some of the lignin fragments from pretreated bamboo substrate and therefore cause a decrease in the lignin content of the substrate. In the present study, lignin was isolated by dioxane extraction of enzyme hydrolysis of ball-milled substrate (CEL method), and the effects of BAE on lignin molecular ...
DOI:
10.1007/s00226-015-0735-7

20. Evidence of 1,4-Dioxane Attenuation at Groundwater Sites Contaminated with Chlorinated Solvents and 1,4-Dioxane

Author:
Adamson David T.; Anderson R. Hunter; Mahendra Shaily; Newell Charles J.
Source:
Environmental Science & Technology 2015 v.49 no.11 pp. 6510-6518
ISSN:
1520-5851
Subject:
bioremediation; correlation; data collection; dioxane; discriminant analysis; dissolved oxygen; groundwater; half life; metals; monitoring; oxidation; solvents; temporal variation; wells; California
Abstract:
... There is a critical need to develop appropriate management strategies for 1,4-dioxane (dioxane) due to its widespread occurrence and perceived recalcitrance at groundwater sites where chlorinated solvents are present. A comprehensive evaluation of California state (GeoTracker) and Air Force monitoring records was used to provide significant evidence of dioxane attenuation at field sites. Temporal ...
DOI:
10.1021/acs.est.5b00964

21. Experimental Investigation and Thermodynamic Assessment of Phase Equilibria in the PLLA/Dioxane/Water Ternary System for Applications in the Biomedical Field

Author:
Ruggiero Flavia; Netti Paolo Antonio; Torino Enza
Source:
Langmuir 2015 v.31 no.47 pp. 13003-13010
ISSN:
1520-5827
Subject:
biodegradability; calorimetry; dioxane; hydrogen bonding; interface phenomena; medical equipment; nanomaterials; physical phases; polylactic acid; separation; solvents; thermodynamics; tissues; titration
Abstract:
... Fundamental understanding of thermodynamic of phase separation plays a key role in tuning the desired features of biomedical devices. In particular, phase separation of ternary solution is of remarkable interest in processes to obtain biodegradable and biocompatible architectures applied as artificial devices to repair, replace, or support damaged tissues or organs. In these perspectives, thermall ...
DOI:
10.1021/acs.langmuir.5b02460

22. Fabrication of a high-flux thin film composite hollow fiber nanofiltration membrane for wastewater treatment

Author:
Tian-Yin Liu; Li-Xia Bian; Hao-Ge Yuan; Bo Pang; Ya-Kai Lin; Yu Tong; Bart Van der Bruggen; Xiao-Lin Wang
Source:
Journal of membrane science 2015 v.478 pp. 25-36
ISSN:
0376-7388
Subject:
cyclic ethers; dextran; dioxane; industrial wastewater treatment; nanofiltration; oil and gas industry; organic carbon; permeability; piperazine; polymerization; porosity; tensile strength; thin film composite membranes; total dissolved solids
Abstract:
... A high-flux thin film composite (TFC) hollow fiber nanofiltration (NF) membrane was fabricated using a barrier layer of polypiperazine amide synthesized via interfacial polymerization (IP) on a previously prepared dual-layer (PES/PVDF) hollow fiber substrate, which was synthesized via the two-step TIPS/NIPS method. The permeability of the TFC membrane was smaller by an order of magnitude than that ...
DOI:
10.1016/j.memsci.2014.12.029

23. Fabrication of a thin film nanocomposite hollow fiber nanofiltration membrane for wastewater treatment

Author:
Tian-Yin Liu; Zai-Hao Liu; Rui-Xin Zhang; Yao Wang; Bart Van der Bruggen; Xiao-Lin Wang
Source:
Journal of membrane science 2015 v.488 pp. 92-102
ISSN:
0376-7388
Subject:
artificial membranes; crosslinking; dioxane; drinking water; electrolytes; hydrophilicity; industrial wastewater treatment; nanocomposites; nanofiltration; nanoparticles; nanopores; permeability; phosphates; pollutants; polymerization; thermoplastics; water purification
Abstract:
... A thin film nanocomposite (TFN) hollow fiber membrane containing nanoporous SAPO-34 nanoparticles was prepared on the dual-layer (PES/PVDF) hollow fiber substrate. The nanoparticle exposed TFN membrane (TFN(DOX)) was fabricated via the co-solvent (dioxane) assisted interfacial polymerization process. The TFN(DOX) had a larger nanoporosity and a higher crosslinking degree, which simultaneously led ...
DOI:
10.1016/j.memsci.2015.04.020

24. HRP-mediated polyacrylamide graft modification of raw jute fabric

Author:
Ruirui Liu; Aixue Dong; Xuerong Fan; Qiang Wang; Yuanyuan Yu; Artur Cavaco-Paulo
Source:
Journal of molecular catalysis 2015 v.116 pp. 29-38
ISSN:
1381-1177
Subject:
Fourier transform infrared spectroscopy; acrylamides; aromatic compounds; catalytic activity; contact angle; dioxane; fabrics; gel chromatography; hydrophilicity; jute; lignin; mass spectrometry; nitrogen content; nuclear magnetic resonance spectroscopy; peroxidase; polyacrylamide; polymerization; scanning electron microscopy
Abstract:
... The horseradish peroxidase (HRP)/hydrogen peroxide system can catalyze the free-radical polymerization of aromatic compounds such as lignins. In this study, to improve the hydrophilicity of lignin-rich jute fabrics, acrylamide (AM) was grafted onto their surface by HRP-mediated oxidative polymerization. The resulting AM-lignin graft polymer in jute fibers, from which the lignin was removed by extr ...
DOI:
10.1016/j.molcatb.2015.03.004

25. Highly ordered monolithic structures by directional freezing and UV-initiated cryopolymerisation. Evaluation as stationary phases in high performance liquid chromatography

Author:
R. Dario Arrua; Emily F. Hilder
Source:
RSC advances 2015 v.5 no.87 pp. 71131-71138
ISSN:
2046-2069
Subject:
biochemical compounds; composite polymers; crystals; dioxane; freezing; high performance liquid chromatography; hydrophobic interaction chromatography; liquid nitrogen; polyethylene glycol; polymerization; porous media; solvents; temperature
Abstract:
... Rigid aligned polymers were prepared by directional freezing and photo-initiated cryopolymerisation. Poly[poly(ethyleneglycol) diacrylate] (polyPEGDA) and poly(butyl methacrylate-co-ethylene glycol dimethacrylate) [poly(BuMA-co-EDMA)] macroporous polymers were prepared by directional freezing of the polymerisation mixture in liquid nitrogen and photo-initiated polymerisation in the frozen state. T ...
DOI:
10.1039/c5ra15114g

26. How Well Do MWL and CEL Preparations Represent the Whole Hardwood Lignin?

Author:
Ewellyn Capanema; Mikhail Balakshin; Rui Katahira; Hou-min Chang; Hasan Jameel
Source:
Journal of wood chemistry and technology 2015 v.35 no.1 pp. 17-26
ISSN:
1532-2319
Subject:
chemistry; dioxane; enzymatic hydrolysis; hardwood; lignin; milling; nuclear magnetic resonance spectroscopy
Abstract:
... Hardwood lignin preparations were isolated using classical milled wood lignin (MWL) and cellulolytic enzyme lignin (CEL) protocols. Furthermore, we managed to produce a lignin preparation of a very high yield, above 90%, with high purity and minimal structural degradation. This was achieved by dissolution and regeneration of milled wood prior to enzymatic hydrolysis, along with the use of 80% diox ...
DOI:
10.1080/02773813.2014.892993

27. Immobilization of trypsin in organic and aqueous media for enzymatic peptide synthesis and hydrolysis reactions

Author:
Julia Stolarow; Manuel Heinzelmann; Wladimir Yeremchuk; Christoph Syldatk; Rudolf Hausmann
Source:
BMC biotechnology 2015 v.15 no.1 pp. 77
ISSN:
1472-6750
Subject:
aqueous solutions; dioxane; drugs; enzyme activity; hydrolysis; magnetism; mass transfer; microparticles; models; peptides; solvents; swine; trypsin
Abstract:
... BACKGROUND: Immobilization of enzymes onto different carriers increases enzyme’s stability and reusability within biotechnological and pharmaceutical applications. However, some immobilization techniques are associated with loss of enzymatic specificity and/or activity. Possible reasons for this loss are mass transport limitations or structural changes. For this reason an immobilization method mus ...
DOI:
10.1186/s12896-015-0196-y
PubMed:
26286267
PubMed Central:
PMC4545374

28. Importance of solvent association in the estimation of antioxidant properties of phenolic compounds by DPPH method

Author:
Andrzej L. Dawidowicz; Małgorzata Olszowy; Małgorzata Jóźwik-Dolęba
Source:
Journal of food science and technology 2015 v.52 no.7 pp. 4523-4529
ISSN:
0022-1155
Subject:
2,2-diphenyl-1-picrylhydrazyl; antioxidant activity; antioxidants; butylated hydroxyanisole; butylated hydroxytoluene; caffeic acid; dioxane; dissociation; energy; ethyl acetate; ferulic acid; gallic acid; methanol; solvents; temperature
Abstract:
... The presented paper shows the influence of temperature increase in the range typically used during antioxidant measurements (15–35 °C) on the estimation of antioxidant properties of phenolic compounds (caffeic acid, ferulic acid, gallic acid, trolox, butylhydroxyanisole, butylhydroxytoluene and 2,6-diisopropylphenol) in associating and non-associating solvents. A significant influence of temperatu ...
DOI:
10.1007/s13197-014-1451-2
PubMed:
26139920
PubMed Central:
PMC4486522

29. In(OTf)3-mediated synthesis of substituted pyridazines

Author:
Meng-Yang Chang; Yi-Ju Lu; Yu-Chieh Cheng
Source:
Tetrahedron 2015 v.71 pp. 6840-6845
ISSN:
0040-4020
Subject:
chemical reactions; chemical structure; dioxane; pyridazines
Abstract:
... In(OTf)3 (4c)-mediated one-pot (4+2) cyclocondensation of γ-alkynones 3 with N2H4(aq) in dioxane affords substituted pyridazines 5 in good yields via a sequential desulfonative or dehydrogenative aromatization. The facile transformation proceeds by a facile synthetic sequence starting with an α-propargylation of β-ketosulfones 1 and a cyclocondensation of γ-alkynones 3 with N2H4(aq). The method pr ...
DOI:
10.1016/j.tet.2015.07.025

30. In-situ activation of persulfate by iron filings and degradation of 1,4-dioxane

Author:
Hua Zhong; Mark L. Brusseau; Yake Wang; Ni Yan; Lauren Quig; Gwynn R. Johnson
Source:
Water research 2015 v.83 pp. 104-111
ISSN:
0043-1354
Subject:
X-ray diffraction; dioxane; electron paramagnetic resonance spectroscopy; energy-dispersive X-ray analysis; free radicals; groundwater; iron; oxidation; pH; quartz; sand; scanning electron microscopy; sulfates
Abstract:
... Activation of persulfate by iron filings and subsequent degradation of 1,4-dioxane (dioxane) was studied in both batch-reactor and column systems to evaluate the potential of a persulfate-enhanced permeable reactive barrier (PRB) system for combined oxidative-reductive removal of organic contaminants from groundwater. In batch experiments, decomposition of persulfate to sulfate and degradation of ...
DOI:
10.1016/j.watres.2015.06.025
PubMed:
26141426
PubMed Central:
PMC4546906

31. Influence of the composition of water–organic mixtures and the properties of organic solvents on thermochemical characteristics of l-methionine dissolution at 298.15K

Author:
Valeriy I. Smirnov; Valentin G. Badelin
Source:
Thermochimica acta 2015 v.616 pp. 20-26
ISSN:
0040-6031
Subject:
acetone; acetonitrile; acidity; amino acids; aqueous solutions; calorimetry; chemical interactions; cohesion; dimethyl sulfoxide; dimethylformamide; dioxane; energy; energy density; enthalpy; solvents
Abstract:
... The enthalpies of l-methionine dissolution in aqueous solution of acetonitrile, 1,4-dioxane, acetone, dimethylsulfoxide, formamide, N-methylformamide, N,N-dimethylformamide and N,N-dimethylacetamide were determined by calorimetric method at 298.15K and organic solvent mole fractions up to x2∼0.35. The standard enthalpies of solution (ΔsolH°) and transfer (ΔtrH°) of l-methionine from water to a mix ...
DOI:
10.1016/j.tca.2015.08.006

32. Isolation and Structural Characterization of the Milled Wood Lignin, Dioxane Lignin, and Cellulolytic Lignin Preparations from Brewer’s Spent Grain

Author:
Jorge Rencoret; Pepijn Prinsen; Ana Gutierrez; Angel T. Martinez; Jose C. del Rio
Source:
Journal of agricultural and food chemistry 2015 v.63 no.2 pp. 603-613
ISSN:
0021-8561
Subject:
acetates; derivatization; dioxane; ethers; gas chromatography-mass spectrometry; grasses; lignin; nuclear magnetic resonance spectroscopy; pyrolysis; resinols; spent grains; wood
Abstract:
... The structure of the lignin from brewer’s spent grain (BSG) has been studied in detail. Three different lignin preparations, the so-called “milled-wood” lignin (MWL), dioxane lignin (DL), and cellulolytic lignin (CEL), were isolated from BSG and then thoroughly characterized by pyrolysis GC/MS, 2D-NMR, and derivatization followed by reductive cleavage (DFRC). The data indicated that BSG lign ...
DOI:
10.1021/jf505808c

33. Lewis-acid catalyzed N-acyliminium ion cyclodimerization: synthesis of symmetrical 1,4-dioxanes

Author:
Bakhat Ali; Julio Zukerman-Schpector; Fernando P. Ferreira; Anwar Shamim; Daniel C. Pimenta; Hélio A. Stefani
Source:
Tetrahedron letters 2015 v.56 no.9 pp. 1153-1158
ISSN:
0040-4039
Subject:
Lewis acids; catalytic activity; chemical reactions; chemical structure; dioxane; hydrochloric acid
Abstract:
... The cyclodimerization reaction of N-substituted-5-hydroxy-pyrrolydinones promoted by BF3·Et2O and HCl to obtain symmetrical 1,4-dioxane derivatives was achieved in moderate to good yields, mild conditions, and short reaction times. These transformations render a promising alternative route that provides access to diverse 1,4-dioxane derivatives with a wide structural diversity. ...
DOI:
10.1016/j.tetlet.2015.01.059

34. Ligand and copper free Sonogashira coupling to achieve 2-alkynyl d-glucal derivatives: regioselective electrophile promoted nucleophilic 5-endo-dig cyclization

Author:
Anwar Shamim; Stanley N.S. Vasconcelos; Bakhat Ali; Lucas Sousa Madureira; J. Zukerman-Schpector; Hélio A. Stefani
Source:
Tetrahedron letters 2015 v.56 no.43 pp. 5836-5842
ISSN:
0040-4039
Subject:
Lewis acids; Lewis bases; acetates; alkynes; ambient temperature; chemical reactions; chemical structure; chlorides; copper; dioxane; ligands; palladium; regioselectivity
Abstract:
... A general approach for the synthesis of 2-alkynyl-d-glucal derivatives has been achieved through a ligand and copper-free Sonogashira coupling of 2-iodo-3,4,6-tri-O-acetyl-d-glucal and terminal alkynes using palladium acetate in DMF at room temperature with very good to excellent yields. The scope of this reaction is shown by regioselective electrophile promoted nucleophilic (EPN) 5-endo-dig cycli ...
DOI:
10.1016/j.tetlet.2015.08.052

35. Metal-coordination-driven mixed ligand binding in supramolecular bisporphyrin tweezers

Author:
Sk Asif Ikbal; Avinash Dhamija; Sankar Prasad Rath
Source:
Chemical communications 2015 v.51 no.74 pp. 14107-14110
ISSN:
1364-548X
Subject:
X-radiation; chemical reactions; dioxane; ligands; magnesium; mixing; nuclear magnetic resonance spectroscopy; polymers; pyrazines; pyrimidines; ultraviolet-visible spectroscopy
Abstract:
... Mg(ii)bisporphyrin has been used as an efficient host for the selective binding of guest ligands. In the presence of heterogeneous guest pairs, 2-aminopyrimidine/pyrazine and 2-aminopyrimidine/1,4-dioxane, 2-aminopyrimidine is bound selectively inside the bisporphyrin cavity whereas pyrazine/1,4-dioxane is bound outside to produce 1D mixed ligand polymers. UV-vis, ¹H NMR spectra and X-ray structur ...
DOI:
10.1039/c5cc04882f

36. Multifaceted Synthetic Route to Functional Polyacrylates by Transesterification of Poly(pentafluorophenyl acrylates)

Author:
Das Anindita; Theato Patrick
Source:
Macromolecules 2015 v.48 no.24 pp. 8695-8707
ISSN:
1520-5835
Subject:
Fourier transform infrared spectroscopy; Lewis bases; acrylates; alkynes; amino acids; carbon dioxide; catalytic activity; composite polymers; crosslinking; dimethylformamide; dioxane; geraniol; hydrogels; lactic acid; natural resources; pH; polyacrylic acid; solvents; transesterification; zwitterions
Abstract:
... Synthesis of functional polyacrylates by 4-dimethylaminopyridine (DMAP) catalyzed trans-esterification of poly(pentafluorophenyl acrylate) (polyPFPA) is reported. High fidelity and versatility of this strategy was exemplified by near quantitative conversion with diverse functional alcohols (primary, secondary as well as phenolic) featuring reactive groups like alkene, alkyne or acrylate, enabling ...
DOI:
10.1021/acs.macromol.5b02293

37. Multifunctional polybenzoxazine nanocomposites containing photoresponsive azobenzene units, catalytic carboxylic acid groups, and pyrene units capable of dispersing carbon nanotubes

Author:
Mohamed Gamal Mohamed; Chi-Hui Hsiao; Faliang Luo; Lizong Dai; Shiao-Wei Kuo
Source:
RSC advances 2015 v.5 no.56 pp. 45201-45212
ISSN:
2046-2069
Subject:
Fourier transform infrared spectroscopy; benzoic acid; carbon nanotubes; carboxylic acids; catalysts; catalytic activity; dioxane; dispersibility; heat production; moieties; nanocomposites; polymerization; temperature; thermal stability; thermogravimetry
Abstract:
... In this study, we synthesized a new multifunctional benzoxazine monomer Azo-COOH-Py BZ—featuring an azobenzene unit, a carboxylic acid group, and a pyrene moiety—through the reaction of 4-(4-hydroxyphenylazo)benzoic acid (Azo-COOH), paraformaldehyde, and aminopyrene (Py-NH₂) in 1,4-dioxane. Fourier transform infrared (FTIR) spectroscopy and ¹H and ¹³C nuclear magnetic resonance spectroscopy confir ...
DOI:
10.1039/c5ra07983g

38. Muscadine grape seed oil as a novel source of tocotrienols to reduce adipogenesis and adipocyte inflammation

Author:
Lu Zhao; Yavuz Yagiz; Changmou Xu; Jiang Lu; Soonkyu Chung; Maurice R. Marshall
Source:
Food & function 2015 v.6 no.7 pp. 2293-2302
ISSN:
2042-650X
Subject:
Vitis rotundifolia; adipocytes; adipogenesis; anti-inflammatory activity; dioxane; gamma-tocotrienol; gene expression; grapeseed oil; hexane; humans; inflammation; interleukin-6; interleukin-8; messenger RNA; obesity; olive oil; peroxisome proliferator-activated receptor gamma; protein synthesis; rice bran; seasonal variation; secretion; solid phase extraction; stem cells; triacylglycerols
Abstract:
... Tocotrienols are unsaturated forms of vitamin E previously shown to reduce adipogenesis and adipose inflammation. In this study, muscadine grape seed oil (MGSO) was identified as a novel source of tocotrienols containing significant amounts of α- and γ-tocotrienol (T3) with minor seasonal changes. The aim of this study was to assess the anti-adipogenic and anti-inflammatory potential of MGSO by us ...
DOI:
10.1039/c5fo00261c

39. Nature of reactant and influence of water on the supramolecular patterns and luminescent properties of organic salts comprising (1,1′-biphenyl)-4,4′-disulfonate and triphenylmethanaminium

Author:
Ya-Nan Li; Li-Hua Huo; Zhao-Peng Deng; Xin-Yu Xie; Zhi-Biao Zhu; Shan Gao
Source:
RSC advances 2015 v.5 no.52 pp. 41692-41706
ISSN:
2046-2069
Subject:
X-ray diffraction; amines; cations; dimethyl sulfoxide; dioxane; emissions factor; ethanol; hydrogen bonding; luminescence; methanol; organic salts; solvents; sulfonates; thermogravimetry
Abstract:
... The solvent reaction of 1,1′-biphenyl-4,4′-disulfonic acid (H₂BPDSA) and triphenylmethylamine (TPMA) gives rise to fourteen supramolecular compounds, namely, 2(HTPMA)⁺·(BPDSA)²⁻·(H₂O) (1), 2(HTPMA)⁺·(BPDSA)²⁻·(MeOH) (2), 2(HTPMA)⁺·(BPDSA)²⁻·(EtOH) (3), 2(HTPMA)⁺·(BPDSA)²⁻·3(n-PrOH) (4), 2(HTPMA)⁺·(BPDSA)²⁻·2(n-BuOH) (5), 2(HTPMA)⁺·(BPDSA)²⁻·2(n-PeOH) (6), 2(HTPMA)⁺·(BPDSA)²⁻·4(DMF) (7), 2(HTPMA)⁺· ...
DOI:
10.1039/c5ra04497a

40. New antimalarial 3-methoxy-1,2-dioxanes: optimization of cellular pharmacokinetics and pharmacodynamics properties by incorporation of amino and N-heterocyclic moieties at C4

Author:
D. P. Sonawane; M. Persico; Y. Corbett; G. Chianese; A. Di Dato; C. Fattorusso; O. Taglialatela-Scafati; D. Taramelli; C. Trombini; D. D. Dhavale; A. Quintavalla; M. Lombardo
Source:
RSC advances 2015 v.5 no.89 pp. 72995-73010
ISSN:
2046-2069
Subject:
Plasmodium falciparum; chloroquine; cytotoxicity; dioxane; endothelial cells; inhibitory concentration 50; moieties; pharmacodynamics; pharmacokinetics; structure-activity relationships
Abstract:
... A new series of nineteen 3-methoxy-1,2-dioxanes containing an amino moiety at C4 was designed, synthesized and tested for in vitro antimalarial activity against chloroquine sensitive (CQ-S) D10 and chloroquine resistant (CQ-R) W2 strains of Plasmodium falciparum (Pf). Cytotoxicity against the human endothelial cell line (HMEC-1) was also evaluated. The introduced modifications resulted in a notabl ...
DOI:
10.1039/c5ra10785g

41. Novel biodegradable poly(propylene fumarate)-co-poly(l-lactic acid) porous scaffolds fabricated by phase separation for tissue engineering applications

Author:
Xifeng Liu; A. Lee Miller II; Brian E. Waletzki; Michael J. Yaszemski; Lichun Lu
Source:
RSC advances 2015 v.5 no.27 pp. 21301-21309
ISSN:
2046-2069
Subject:
adsorption; biodegradability; bones; composite polymers; dioxane; fumarates; hydrophobicity; medicine; propylene; separation; temperature; thermal properties; tissue engineering
Abstract:
... Scaffolds with intrinsically interconnected porous structures are highly desirable in tissue engineering and regenerative medicine. In this study, three-dimensional polymer scaffolds with highly interconnected porous structures were fabricated by thermally induced phase separation of novel synthesized biodegradable poly(propylene fumarate)-co-poly(l-lactic acid) in a dioxane/water binary system. D ...
DOI:
10.1039/c5ra00508f
PubMed:
26989483
PubMed Central:
PMC4792309

42. On the rearrangement of some Z-arylhydrazones of 3-benzoyl-5-phenylisoxazoles into 2-aryl-4-phenacyl-2H-1,2,3-triazoles: a kinetic study of the substituent effects in Boulton–Katritzky reactions

Author:
Vincenzo Frenna; Antonio Palumbo Piccionello; Domenico Spinelli; Franco Ghelfi
Source:
Tetrahedron 2015 v.71 pp. 7315-7322
ISSN:
0040-4020
Subject:
Gibbs free energy; chemical reactions; chemical structure; data collection; dioxane; temperature
Abstract:
... The rearrangement of eight new Z-arylhydrazones of 3-benzoyl-5-phenylisoxazoles (3d–k) into the relevant 2-aryl-4-phenacyl-2H-1,2,3-triazoles (4d–k) in dioxane/water solution at different proton concentrations has been quantitatively studied in a wide temperature range (293–333 K). The data collected together with some our previous ones on compounds 3a–c have allowed a deep study of the substituen ...
DOI:
10.1016/j.tet.2015.04.007

43. Optimized methods for obtaining cellulose and cellulose sulfates from birch wood

Author:
Boris N. Kuznetsov; Svetlana A. Kuznetsova; Vladimir A. Levdansky; Alexandr V. Levdansky; Natalia Yu. Vasil’eva; Nikolay V. Chesnokov; Natalia M. Ivanchenko; Laurent Djakovitch; Catherine Pinel
Source:
Wood science and technology 2015 v.49 no.4 pp. 825-843
ISSN:
0043-7719
Subject:
Betula; Fourier transform infrared spectroscopy; Raman spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; acetic acid; atomic force microscopy; catalysts; cellulose; delignification; dioxane; hydrogen peroxide; lignin; nuclear magnetic resonance spectroscopy; pyridines; scanning electron microscopy; sulfates; sulfuric acid; wood
Abstract:
... The methods of obtaining cellulose and cellulose sulfates from birch wood based on the use of one-step catalytic delignification of wood by hydrogen peroxide in acetic acid–water medium were studied. The conditions of birch wood oxidative delignification by acetic acid/hydrogen peroxide mixtures in the presence of sulfuric acid catalyst were optimized in order to obtain an acceptable yield of cell ...
DOI:
10.1007/s00226-015-0723-y

44. Photoredox-Catalyzed Tandem Insertion/Cyclization Reactions of Difluoromethyl and 1,1-Difluoroalkyl Radicals with Biphenyl Isocyanides

Author:
Zhang Zuxiao; Tang Xiaojun; Dolbier William R.
Source:
Organic letters 2015 v.17 no.18 pp. 4401-4403
ISSN:
1523-7052
Subject:
ambient temperature; biphenyl; catalysts; chemical structure; cyclization reactions; dioxane; free radicals; oxidation; phenanthridines
Abstract:
... Using visible-light photoredox conditions, difluoromethylation and 1,1-difluoroalkylation of biphenyl isocyanides have allowed the synthesis of a series of 6-(difluoromethyl)- and 6-(1,1-difluoroalkyl)phenanthridines via tandem addition/cyclization/oxidation processes. The reactions are carried out in wet dioxane at room temperature using fac-Ir(ppy)₃ as catalyst to form a large variety of substit ...
DOI:
10.1021/acs.orglett.5b02061

45. Polymer grafting onto polyurethane backbone via Diels–Alder reaction

Author:
Soykan Agar; Hakan Durmaz; Ufuk Saim Gunay; Gurkan Hizal; Umit Tunca
Source:
Journal of polymer science 2015 v.53 no.4 pp. 521-527
ISSN:
0887-624X
Subject:
ambient temperature; anthracenes; composite polymers; dioxane; ethylene glycol; nuclear magnetic resonance spectroscopy; phase transition; polyurethanes; thermal analysis; toluene; ultraviolet-visible spectroscopy
Abstract:
... The aliphatic polyurethane with pendant anthracene moieties (PU‐anthracene) was prepared from polycondensation of anthracen‐9‐yl methyl 3‐hydroxy‐2‐(hydroxymethyl)‐2‐methylpropanoate (anthracene diol), 1 with hexamethylenediisocyanate in the presence of dibutyltindilaurate in CH₂Cl₂at room temperature for 10 days. Thereafter, the PU‐anthracene (Mₙ,GPC= 12,900 g/mol, Mw/Mₙ= 1.87, relative to PS sta ...
DOI:
10.1002/pola.27466

46. Practical and efficient ipso-iodination of arylboronic acids via KF/I2 system

Author:
Francesco Tramutola; Lucia Chiummiento; Maria Funicello; Paolo Lupattelli
Source:
Tetrahedron letters 2015 v.56 no.9 pp. 1122-1123
ISSN:
0040-4039
Subject:
acids; chemical reactions; chemical structure; dioxane; iodine
Abstract:
... A facile and effective iododeboronation of variously substituted aryl and heteroarylboronic acids through activation and subsequent ipso-introduction of iodine is presented. The use of KF and I2 at 80°C in 1,4-dioxane furnishes iodinated compounds in high yields. ...
DOI:
10.1016/j.tetlet.2015.01.040

47. Preparation and characterization of high boiling solvent lignin-based polyurethane film with lignin as the only hydroxyl group provider

Author:
Zhen Jia; Chunxiang Lu; Pucha Zhou; Lu Wang
Source:
RSC advances 2015 v.5 no.66 pp. 53949-53955
ISSN:
2046-2069
Subject:
air; ambient temperature; ash content; boiling; coatings; dioxane; freeze drying; hardness; hydrophilicity; lignin; moieties; nitrogen; polyols; polyurethanes; solvents; tensile strength; thermal properties; thermogravimetry
Abstract:
... A novel diisocyanate-modified lignin-based polyurethane (LPU) film was facilely prepared using renewable lignin as the only hydroxyl group provider at ambient temperature and pressure for the first time. The lignin was extracted through a modified high boiling solvent (HBS) method with 1,4-dioxane as the solvent, and then dried through freeze drying. The ash content of the HBS lignin sample was ab ...
DOI:
10.1039/c5ra09477a

48. Preparation of poly(L-lactic acid) microfiltration membranes by a nonsolvent-induced phase separation method with the aid of surfactants

Author:
Hiromi Minbu; Akihito Ochiai; Tomoyuki Kawase; Masayuki Taniguchi; Douglas R. Lloyd; Takaaki Tanaka
Source:
Journal of membrane science 2015 v.479 pp. 85-94
ISSN:
0376-7388
Subject:
artificial membranes; bacteria; bovine serum albumin; dioxane; industry; microfiltration; polylactic acid; polysorbates; separation; shrinkage; surfactants
Abstract:
... Microfiltration membranes of poly(L-lactic acid) (PLLA) have been prepared by a nonsolvent-induced phase separation method with the aid of surfactants. Surfactants with hydrophilic-lipophilic balance (HLB) values of 14.9–15.6 were found to be useful in reducing the shrinkage in thickness of the PLLA membrane. Among the surfactants examined, Tween 80 was the best for preparing microfiltration membr ...
DOI:
10.1016/j.memsci.2015.01.021

49. Rapid and high-density covalent immobilization of Rhizomucor miehei lipase using a multi component reaction: application in biodiesel production

Author:
Mehdi Mohammadi; Maryam Ashjari; Shaghayegh Dezvarei; Maryam Yousefi; Mohadese Babaki; Javad Mohammadi
Source:
RSC advances 2015 v.5 no.41 pp. 32698-32705
ISSN:
2046-2069
Subject:
1-propanol; Rhizomucor miehei; biodiesel; carboxylic ester hydrolases; dioxane; fatty acid methyl esters; fuel production; immobilized enzymes; isopropyl alcohol; leaching; methanol; nanoparticles; oils; pH; silica; sodium chloride; solvents; thermal stability; transesterification
Abstract:
... Aldehyde-functionalized silica and silica nanoparticles (SBA-15) were prepared as a matrix system for enzyme immobilization. Immobilization of Rhizomucor miehei lipase (RML) on these supports was performed via a multicomponent reaction under extremely mild conditions (25 °C, pH 7). Investigation on the mechanism of this reaction confirmed the Ugi four-component immobilization approach. The loading ...
DOI:
10.1039/c5ra03299g

50. Reductive opening of carbohydrate phenylsulfonylethylidene (PSE) acetals

Author:
Florence Chéry; Elena Cabianca; Arnaud Tatibouët; Ottorino De Lucchi; Thisbe K. Lindhorst; Patrick Rollin
Source:
Carbohydrate research 2015 v.417 pp. 117-124
ISSN:
0008-6215
Subject:
carbohydrates; dioxane; ethers; iodides; regioselectivity; samarium; sodium
Abstract:
... The phenylsulfonylethylidene (PSE) acetal is a relatively new protecting group in carbohydrate chemistry. However, carbohydrate-derived phenylsulfonylethylidene (PSE) acetals show a different behavior in reductive desulfonylation than simple symmetrical acetals. Here we have investigated various SET-type reaction conditions in order to open PSE acetals regioselectively and to produce chiral ω-hydr ...
DOI:
10.1016/j.carres.2015.09.011

51. Removal of dioxane pollutants from water by using Al-doped single walled carbon nanotubes

Author:
Z. Izakmehri; M. Ardjmand; M. Darvish Ganji; E. Babanezhad; A. Heydarinasab
Source:
RSC advances 2015 v.5 no.59 pp. 48124-48132
ISSN:
2046-2069
Subject:
adsorption; aluminum; carbon nanotubes; dioxane; pollutants; pollution control; solvents; toxicity
Abstract:
... The detection and fast enrichment of toxic organic pollutants are challenging issues in the field of environmental science. We have studied the adsorption of dioxane on perfect, defected, and Al-doped CNTs by DFT calculations adopting the vdW forces corrections (vdW-DF). The accuracy of the vdW-DF results have been evaluated against the state-of-the-art B3LYP-D3 level of theory and it was shown th ...
DOI:
10.1039/c5ra07611k

52. Selective enrichment of polyunsaturated fatty acids by hydrolysis of fish oil using immobilized and stabilized Rhizomucor miehei lipase preparations

Author:
Mehdi Mohammadi; Zohreh Habibi; Shaghayegh Dezvarei; Maryam Yousefi; Maryam Ashjari
Source:
Food and bioproducts processing 2015 v.94 pp. 414-421
ISSN:
0960-3085
Subject:
1-propanol; Rhizomucor miehei; acetonitrile; adsorption; biocatalysts; carboxylic ester hydrolases; copper; dimethyl sulfoxide; dioxane; epoxides; fish oils; hydrolysis; isopropyl alcohol; polyunsaturated fatty acids; silica; solvents; thermal stability
Abstract:
... Immobilization of Rhizomucor miehei lipase (RML) by two different methods is reported. In the first approach RML was directly immobilized on epoxy functionalized silica particles in a mild condition. In the other approach and to perform oriented immobilization, the epoxy functionalized support was partially modified by introducing iminodiacetic acid groups fallowed by addition of Cu2+. In this typ ...
DOI:
10.1016/j.fbp.2014.05.007

53. Self-Assembly Behavior of Amphiphilic C60-End-Capped Poly(vinyl ether)s in Water and Dissociation of the Aggregates by the Complexing of the C60 Moieties with Externally Added γ-Cyclodextrins

Author:
Motoyanagi Jin; Kurata Akihiro; Minoda Masahiko
Source:
Langmuir 2015 v.31 no.8 pp. 2256-2261
ISSN:
1520-5827
Subject:
aqueous solutions; dioxane; dissociation; fullerene; gamma-cyclodextrin; hydrophobicity; moieties; polymerization; polymers; solvents; titration
Abstract:
... C₆₀-end-capped polymers consisting of an amphiphilic poly(2-methoxyethyl vinyl ether) (PMOVE) main chain were synthesized by living cationic polymerization using a C₆₀-functionalized initiator (C₆₀VE-TFA) in the presence of EtAlCl₂ as an activator and dioxane as an added base. The obtained polymers (C₆₀-PMOVE) dissolved in a wide range of solvents including water and exhibited solvatochromism depe ...
DOI:
10.1021/la504341s

54. Silver nanoparticle based highly selective and sensitive solvatochromatic sensor for colorimetric detection of 1,4-dioxane in aqueous media

Author:
Anshu Kumar; Gaurav Vyas; Madhuri Bhatt; Shreya Bhatt; Parimal Paul
Source:
Chemical communications 2015 v.51 no.88 pp. 15936-15939
ISSN:
1364-548X
Subject:
chemical reactions; citrates; color; colorimetry; dioxane; groundwater; nanoparticles; nanosilver; reactive oxygen species; silver; vapors
Abstract:
... A citrate stabilised silver nanoparticle (Ci-AgNP) based solvatochromic sensor, which functions as a highly selective and sensitive colorimetric probe for 1,4-dioxane in aqueous media is reported. The surfaces of the AgNPs generate reactive oxygen species, which promote the degradation of 1,4-dioxane assembled in the vicinity of the nanoparticle surfaces through charge transfer interactions. Durin ...
DOI:
10.1039/c5cc06744h

55. Simple and Efficient Furfural Production from Xylose in Media Containing 1-Butyl-3-Methylimidazolium Hydrogen Sulfate

Author:
Peleteiro Susana; da Costa Lopes Andre M.; Garrote Gil; Parajó Juan Carlos; Bogel-Łukasik Rafał
Source:
Industrial & Engineering Chemistry Research 2015 v.54 no.33 pp. 8368-8373
ISSN:
1520-5045
Subject:
catalysts; chemistry; dioxane; engineering; furfural; hydrogen; ionic liquids; sulfates; toluene; xylose
Abstract:
... The acidic 1-butyl-3-methylimidazolium hydrogen sulfate ([bmim][HSO₄]) ionic liquid was explored as both a reaction medium and a catalyst in the furfural production from xylose. Preliminary experiments were carried out at 100–140 °C for 15–480 min in systems containing just xylose dissolved in [bmim][HSO₄] in the absence of externally added catalysts. More than 95% xylose conversion was achieved w ...
DOI:
10.1021/acs.iecr.5b01771

56. Simple and efficient procedures for selective preparation of 3-haloindoles and 2,3-dihaloindoles by using 1,3-dibromo-5,5-dimethylhydantoin and 1,3-dichloro-5,5-dimethylhydantoin

Author:
Jianwei Yan; Tianjun Ni; Fulin Yan
Source:
Tetrahedron letters 2015 v.56 no.9 pp. 1096-1098
ISSN:
0040-4039
Subject:
catalysts; chemical reactions; chemical structure; dioxane; ethylene dichloride; indoles; solvents
Abstract:
... Simple and efficient synthetic procedures for the selective preparation of 3-bromo/3-chloroindoles and 2,3-dibromo/2,3-dichloroindoles by using 1,3-dibromo-5,5-dimethylhydantoin (DBDMH) and 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) were developed. Using 1,4-dioxane as the solvent, a variety of indoles, treated with 0.55equiv DBDMH/DCDMH, afford the corresponding 3-bromo/3-chloroindoles selectivel ...
DOI:
10.1016/j.tetlet.2015.01.080

57. Solvent Effect and Two-Photon Optical Properties of Triphenylamine-Based Donor–Acceptor Fluorophores

Author:
Zhang Yilin; Jiang Meijuan; Han Guang-Chao; Zhao Ke; Tang Ben Zhong; Wong Kam Sing
Source:
The Journal of Physical Chemistry C 2015 v.119 no.49 pp. 27630-27638
ISSN:
1932-7455
Subject:
absorption; acetonitrile; dioxane; fluorescence; fluorescent dyes; hexane; optical properties; photons; solvents
Abstract:
... In this work we present a systematic investigation on the optical properties of two triphenylamine (TPA)-based donor–acceptor fluorophores: TPA-PA (phenylaldehyde) and TPA-BMO ((Z)-4-benzylidene-2-methyloxazol-5(4H)-one). The two compounds are dissolved in nine different organic solvents as dilute solutions in order to analyze the effect of solvent on their linear and nonlinear optical properties. ...
DOI:
10.1021/acs.jpcc.5b06762

58. Solvent Influence on Thickness, Composition, and Morphology Variation with Dip-Coating Rate in Supramolecular PS-b-P4VP Thin Films

Author:
Roland Sébastien; Gamys Cé Guinto; Grosrenaud Josué; Boissé Stéphanie; Pellerin Christian; Prud’homme Robert E.; Bazuin C. Geraldine
Source:
Macromolecules 2015 v.48 no.14 pp. 4823-4834
ISSN:
1520-5835
Subject:
capillarity; chloroform; composite polymers; dioxane; drying; evaporation rate; hardness; hydrogen bonding; micelles; solvents; toluene
Abstract:
... Recent literature has shown that the thickness of dip-coated films has a V-shaped dependence on dip-coating rate when very slow rates are included. For supramolecular block copolymer films, small molecule (SM) uptake and film morphology are also rate-dependent, as shown previously for a poly(styrene-b-4-vinylpyridine) (PS–P4VP) block copolymer in THF solutions containing naphthol (NOH) and naphtho ...
DOI:
10.1021/acs.macromol.5b00847

59. Solvent- and Microwave-Assisted Dehydrations of Polyols to Anhydro and Dianhydro Polyols

Author:
Robinson J. Michael; Wadle Amber M.; Reno Mark D.; Kidd Ryan; Barrett Hinsz Staci R.; Urquieta Jacqueline
Source:
Energy & Fuels 2015 v.29 no.10 pp. 6529-6535
ISSN:
1520-5029
Subject:
catalysts; dioxane; mannitol; microwave radiation; microwave treatment; solvents; sorbitol; sulfates; sulfuric acid; temperature; xylitol
Abstract:
... Carbohydrate polyol (sorbitol, mannitol, and xylitol) dehydrations by both strong and weak acid catalysts were enhanced by microwave irradiation when performed in aqueous dioxane. Reaction conditions such as the percent of water, type and concentration of acid, reaction time, and temperature were varied. Reactions with different conditions were compared by using the “combined severity” parameter. ...
DOI:
10.1021/acs.energyfuels.5b02167

60. Study to explore assorted interfaces of an ionic liquid prevailing in solvent systems by physicochemical approach

Author:
Tanusree Ray; Mahendra Nath Roy
Source:
RSC advances 2015 v.5 no.109 pp. 89431-89440
ISSN:
2046-2069
Subject:
Fourier transform infrared spectroscopy; acetonitrile; bromine; dioxane; ionic liquids; refractive index; temperature; tetrabutylammonium compounds; tetrahydrofuran; viscosity
Abstract:
... The electrolytic conductivities, densities, viscosities, refractive indices and FT-IR studies of 1-butyl-pyridinium bromide ([bupy]Br) have been studied in 1,4 dioxane, tetrahydrofuran, and acetonitrile at different temperatures. The molar conductivities observed were explained with the manifestation of the formation of ion-pairs and triple ion formation. The limiting ionic conductances have been ...
DOI:
10.1039/c5ra17123g

61. Supramolecular functionalized polybenzoxazines from azobenzene carboxylic acid/azobenzene pyridine complexes: synthesis, surface properties, and specific interactions

Author:
Mohamed Gamal Mohamed; Chi-Hui Hsiao; Kuo-Chih Hsu; Fang-Hsien Lu; His-Kang Shih; Shiao-Wei Kuo
Source:
RSC advances 2015 v.5 no.17 pp. 12763-12772
ISSN:
2046-2069
Subject:
Fourier transform infrared spectroscopy; aniline; azo compounds; benzoic acid; carboxylic acids; contact angle; diazonium compounds; dioxane; heat production; hydrogen bonding; moieties; nuclear magnetic resonance spectroscopy; phenol; polymerization; pyridines; sodium hydroxide; sodium nitrite; temperature; thermogravimetry
Abstract:
... In this study we synthesized Azo-COOH BZ, a new benzoxazine derivative containing both azobenzene and carboxylic acid units, through the reaction of 4-(4-hydroxphenylazo)benzoic acid (Azo-COOH, itself prepared through a diazonium reaction of 4-aminobenzoic acid with phenol in the presence sodium nitrite and NaOH) with paraformaldehyde and aniline in 1,4-dioxane. Fourier transform infrared (FTIR) s ...
DOI:
10.1039/c4ra15107k

62. Synthesis and characterization of nanostructured PS-b-P4VP/Fe₂O₃ thin films with magnetic properties prepared by solvent vapor annealing

Author:
I. Barandiaran; G. Kortaberria
Source:
RSC advances 2015 v.5 no.116 pp. 95840-95846
ISSN:
2046-2069
Subject:
annealing; composite polymers; dioxane; exposure duration; ferric oxide; films (materials); maghemite; magnetic properties; magnetism; nanocomposites; nanoparticles; solvents; vapors
Abstract:
... In this work hybrid organic/inorganic nanocomposites with magnetic properties, based on a PS-b-P4VP block copolymer and Fe₂O₃ maghemite nanoparticles have been prepared. The nanoparticles were surface modified with PS brushes by the grafting through method. The morphology of the neat block copolymer and nanocomposites was analyzed by AFM. For nanostructuring, thin films were annealed under dioxane ...
DOI:
10.1039/c5ra21477g

63. Synthesis and enzymatic resolution of racemic 2,3-epoxy propyl esters obtained from glycerol

Author:
Yara Jaqueline Kerber Araujo; Naga Prasad Avvari; Derisvaldo Rosa Paiva; Dênis Pires de Lima; Adilson Beatriz
Source:
Tetrahedron letters 2015 v.56 no.13 pp. 1696-1698
ISSN:
0040-4039
Subject:
Thermomyces; butyrates; carboxylic acids; carboxylic ester hydrolases; catalysts; chemical reactions; chemical structure; dioxane; epichlorohydrins; glycerol; potassium; salts; sodium
Abstract:
... A method is described for the synthesis of (±)-2,3-epoxy propyl esters from glycerol, involving reaction of epichlorohydrin with sodium or potassium salts of carboxylic acids in the presence of TBAB as catalyst, with moderate to excellent yields. Kinetic resolution of glycidyl butyrate by lipase of Thermomyces lanuginosa has been achieved with remarkable enantiomeric excess (ee >99%) using 1,4-dio ...
DOI:
10.1016/j.tetlet.2015.02.046

64. Synthesis of Fullerene-Fused Dioxanes/Dioxepanes: Ferric Perchlorate-Mediated One-Step Reaction of [60]Fullerene with Diols

Author:
Zhang Xiao-Feng; Li Fa-Bao; Wu Jun; Shi Ji-Long; Liu Zhan; Liu Li
Source:
Journal of organic chemistry 2015 v.80 no.12 pp. 6037-6043
ISSN:
1520-6904
Subject:
chemical reactions; chemical structure; diethylene glycol; dioxane; ethers; fullerene; organic chemistry; perchlorates; reaction mechanisms; triethylene glycol
Abstract:
... The facile one-step reaction of [60]fullerene with various diols in the presence of ferric perchlorate afforded a series of rare fullerene-fused dioxanes/dioxepanes. Nevertheless, the reaction of [60]fullerene with diethylene glycol, triethylene glycol, and tripropylene glycol promoted by ferric perchlorate unexpectedly generated fullerene-fused dioxanes instead of the anticipated fullerene-fused ...
DOI:
10.1021/acs.joc.5b00360

65. Synthesis of endoperoxides by domino reactions of ketones and molecular oxygen

Author:
L. Novkovic; M. Trmcic; M. Rodic; F. Bihelovic; M. Zlatar; R. Matovic; R. N. Saicic
Source:
RSC advances 2015 v.5 no.120 pp. 99577-99584
ISSN:
2046-2069
Subject:
dioxane; ketones; oxygen; potassium hydroxide; potassium tert-butoxide
Abstract:
... Domino reactions of ketones with molecular oxygen in the presence of potassium hydroxide and potassium t-butoxide afford cyclic hydroperoxy acetals (3,5-dihydroxy-1,2-dioxanes). Mixed endoperoxides can also be obtained in a three-component reaction of two ketones and oxygen. ...
DOI:
10.1039/c5ra13476e

66. Tacticity Separation of Poly(methyl methacrylate) by Multidetector Thermal Field-Flow Fractionation

Author:
Greyling Guilaume; Pasch Harald
Source:
Analytical chemistry 2015 v.87 no.5 pp. 3011-3018
ISSN:
1520-6882
Subject:
acetonitrile; diffusivity; dioxane; fractionation; isomers; microstructure; molecular weight; nuclear magnetic resonance spectroscopy; polymethylmethacrylate; solvents; tetrahydrofuran
Abstract:
... For the first time, thermal field-flow fractionation (ThFFF) has been used for the separation of poly(methyl methacrylate) (PMMA) with regard to molecular microstructure. PMMA exists in three different isomeric forms, namely, isotactic, syndiotactic, and atactic. ThFFF analysis of the different PMMA isomers in tetrahydrofuran, acetonitrile (ACN), and dioxane reveals that isomers with similar molec ...
DOI:
10.1021/ac504651p

67. Temperature-Invariant Aqueous Microgels as Hosts for Biomacromolecules

Author:
Mastour Tehrani Sepehr; Lu Yijie; Guerin Gerald; Soleimani Mohsen; Pichugin Dmitry; Winnik Mitchell A.
Source:
Biomacromolecules 2015 v.16 no.10 pp. 3134-3144
ISSN:
1526-4602
Subject:
acetone; aminolysis; annealing; catalytic activity; chemical bonding; denaturation; dioxane; enzymatic reactions; enzyme stability; ethanolamine; hydrogels; methanol; peroxidase; polyacrylamide; polymerization; solvents; temperature; thermal stability
Abstract:
... Immobilization of enzymes on solid supports has been widely used to improve enzyme recycling, enzyme stability, and performance. We are interested in using aqueous microgels (colloidal hydrogels) as carriers for enzymes used in high-temperature reactions. These microgels should maintain their volume and colloidal stability in aqueous media up to 100 °C to serve as thermo-stable supports for enzyme ...
DOI:
10.1021/acs.biomac.5b00768

68. Thermal property of an aggregation-induced emission fluorophore that forms metal–ligand complexes with Zn(ClO₄)₂ of salicylaldehyde azine-functionalized polybenzoxazine

Author:
Mohamed Gamal Mohamed; Ruey-Chorng Lin; Jia-Huei Tu; Fang-Hsien Lu; Jin-Long Hong; Kwang-Un Jeong; Chih-Feng Wang; Shiao-Wei Kuo
Source:
RSC advances 2015 v.5 no.80 pp. 65635-65645
ISSN:
2046-2069
Subject:
aniline; condensation reactions; crosslinking; differential scanning calorimetry; dioxane; fluorescence; fluorescent dyes; heat production; hydrazine; hydroxybenzaldehyde; metal ions; mixing; perchlorates; photoluminescence; polymerization; temperature; thermal properties; thermogravimetry; zinc
Abstract:
... In this report, we designed a new and simple salicylaldehyde azine-functionalized benzoxazine (azine-BZ) monomer via Mannich condensation reaction of aniline and paraformaldehyde with 1,2-bis(2,4-dihydroxybenzylidene)hydrazine in 1,4-dioxane. Compared with 3-phenyl-3,4-dihydro-2H-benzoxazine monomer (263 °C), the maximum exothermic peak of azine-BZ shifted to a lower temperature (213 °C) based on ...
DOI:
10.1039/c5ra09409g

69. Tocopherol and tocotrienol homologs in parenteral lipid emulsions

Author:
Zhidong Xu; Kevin A. Harvey; Thomas M. Pavlina; Gary P. Zaloga; Rafat A. Siddiqui
Source:
European journal of lipid science and technology 2015 v.117 no.1 pp. 15-22
ISSN:
1438-7697
Subject:
alpha-tocopherol; dioxane; emulsions; fish; gamma-tocopherol; gastrointestinal system; high performance liquid chromatography; humans; hydrophobicity; oils; olives; patients; physicians; quantitative analysis; silica; soybeans; tocotrienols
Abstract:
... Parenteral lipid emulsions, which are made of oils from plant and fish sources, contain different types of tocopherols and tocotrienols (vitamin E homologs). The amount and types of vitamin E homologs in various lipid emulsions vary considerably and are not completely known. The objective of this analysis was to develop a quantitative method to determine levels of all vitamin E homologs in various ...
DOI:
10.1002/ejlt.201400182
PubMed:
25685054
PubMed Central:
PMC4315900

70. Toward an Understanding of Inhomogeneities in Structure of Lignin in Green Solvents Biorefinery. Part 1: Fractionation and Characterization of Lignin

Author:
Sun Yong-Chang; Wang Min; Sun Run-Cang
Source:
ACS sustainable chemistry 2015 v.3 no.10 pp. 2443-2451
ISSN:
2168-0485
Subject:
Tamarix; biorefining; carbohydrates; dioxane; fractionation; gel chromatography; lignin; molecular weight; nuclear magnetic resonance spectroscopy; raw materials; solvents; wood
Abstract:
... To investigate the inhomogeneity of the lignin, milled wood lignin (MWL), organosolv lignin (OL), and alkaline lignin (AL) were sequentially fractionated from Tamarix spp. with dioxane, alkaline organosolv, and alkaline solutions, respectively. The carbohydrates associated with three lignins were comparatively analyzed, and the molecular weight and polydispersity of lignins were determined by gel ...
DOI:
10.1021/acssuschemeng.5b00809

71. Tunable tissue scaffolds fabricated by in situ crosslink in phase separation system

Author:
Xifeng Liu; Wenjian Chen; Carl T. Gustafson; A. Lee Miller II; Brian E. Waletzki; Michael J. Yaszemski; Lichun Lu
Source:
RSC advances 2015 v.5 no.122 pp. 100824-100833
ISSN:
2046-2069
Subject:
biodegradability; cell growth; crosslinking; dioxane; extracellular matrix; fumarates; polymers; propylene; separation; strength (mechanics); tissue engineering; tissue repair
Abstract:
... Three-dimensional (3-D) scaffolds with intrinsic porous structures are desirable in various tissue regeneration applications. In this study, a unique method that combines thermally induced phase separation with a photocrosslinking process was developed for the fabrication of 3-D crosslinked polymer scaffolds with densely interconnected porous structures. Biodegradable poly(propylene fumarate)-co-p ...
DOI:
10.1039/c5ra19406g
PubMed:
26989479
PubMed Central:
PMC4792294

72. Use of Food and Packaging Model Matrices to Investigate the Antioxidant Properties of Biorefinery Grass Lignins

Author:
Veronique Aguie-Beghin; Laurence Foulon; Paola Soto; David Cronier; Elena Corti; Frederic Legee; Laurent Cezard; Bridgitte Chabbert; Marie-Noelle Maillard; Wouter J. J. Huijgen; Stephanie Baumberger
Source:
Journal of agricultural and food chemistry 2015 v.63 no.45 pp. 10022-10031
ISSN:
0021-8561
Subject:
2,2-diphenyl-1-picrylhydrazyl; antioxidant activity; biorefining; cellulose; depolymerization; dioxane; ethanol; films (materials); food packaging; free radical scavengers; free radicals; grasses; lignin; linoleic acid; oxidation; rosemary
Abstract:
... The antioxidant properties of grass lignins recovered from an alkaline industrial process and from different ethanol organosolv pretreatment processes were compared using two types of tests: (i) classical radical 2,2′-diphenyl-1-picrylhydrazyl (DPPH•) scavenging tests in dioxane/water or ethanol and (ii) tests involving multiphasic systems (lipid dispersion in water or cellulose film suspended in ...
DOI:
10.1021/acs.jafc.5b03686

73. Use of Gamma-Valerolactone as an Illuminating Liquid and Lighter Fluid

Author:
Fábos Viktória; Lui Matthew Y.; Mui Yiu Fung; Wong Yuet Yan; Mika László T.; Qi Long; Cséfalvay Edit; Kovács Viktória; Szűcs Tibor; Horváth István T.
Source:
ACS sustainable chemistry 2015 v.3 no.9 pp. 1899-1904
ISSN:
2168-0485
Subject:
ammonia; ammonium sulfate; catalysts; charcoal; dioxane; ethanol; formic acid; glass; lamps; levulinic acid; neutralization; odors; smoke; sulfuric acid; volatile organic compounds
Abstract:
... The sulfuric acid-catalyzed conversion of paper wastes in gamma-valerolactone (GVL) or dioxane leads to the formation of levulinic acid (LA) and formic acid (FA), which can be converted to GVL by transfer-hydrogenation using the Shvo catalyst in situ or separately. The isolation of LA and FA was assisted by the neutralization of the sulfuric acid with ammonia to form a biphasic system. While the a ...
DOI:
10.1021/acssuschemeng.5b00465

74. Use of quantitative structure–property relationships to study the solvation process of 18-crown-6

Author:
Marina Reis; Nelson Nunes; Ruben Elvas- Leitão; Filomena Martins
Source:
Thermochimica acta 2015 v.604 pp. 140-144
ISSN:
0040-6031
Subject:
dioxane; enthalpy; models; quantitative structure-activity relationships; solutes; solvents
Abstract:
... Solution enthalpies of 18-crown-6 have been obtained for a set of 14 protic and aprotic solvents at 298.15K. The complementary use of Solomonov’s methodology and a QSPR-based approach allowed the identification of the most significant solvent descriptors that model the interaction enthalpy contribution of the solution process (ΔintHᴬ/S). Results were compared with data previously obtained for 1,4- ...
DOI:
10.1016/j.tca.2015.02.005