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1. Partition efficiencies of three different coiled columns for the coil satellite centrifuge at higher rotation speed combinations

Author:
Shinomiya, Kazufusa; Zaima, Kazumasa; Yasue, Miho; Honda, Rika; Sakuma, Yoshiyuki; Harikai, Naoki; Tokura, Koji; Ito, Yoichiro
Source:
Journal of chromatography 2019 v.1596 pp. 134-141
ISSN:
0021-9673
Subject:
solvents,   etc   ; chromatography; satellites; sugars;     Show all 4 Subjects
Abstract:
... The partition efficiencies of three different coiled columns, conventional multilayer coiled column, eccentric coiled column and toroidal coiled column, were evaluated by the separation of 4-methylumbelliferyl sugar derivatives using the coil satellite centrifuge (CSC) with an organic-aqueous two-phase solvent system composed of ethyl acetate/1-butanol/water. The CSC apparatus was reinforced the p ...
DOI:
10.1016/j.chroma.2019.03.010

2. Development of a solvent-reagent selection guide for the formation of thioesters

Author:
Jordan, Andrew; Sneddon, Helen F.
Source:
Green chemistry 2019 v.21 no.8 pp. 1900-1906
ISSN:
1463-9270
Subject:
solvents,   etc   ; green chemistry; thioesters;     Show all 3 Subjects
Abstract:
... For the first time a solvent-reagent guide has been developed with a view to providing greener synthetic conditions for the preparation of thioesters. A number of solvents and reagents were evaluated and optimum conditions were applied to the synthesis of pharmaceutically relevant building block-like molecules. ...
DOI:
10.1039/c9gc00355j

3. Dendrimers in Solution of Linear Polymers: Crowding Effects

Author:
Wengenmayr, Martin; Dockhorn, Ron; Sommer, Jens-Uwe
Source:
Macromolecules 2019 v.52 no.6 pp. 2616-2626
ISSN:
1520-5835
Subject:
solvents,   etc   ; dendrimers; statistics;     Show all 3 Subjects
Abstract:
... We study dendrimers embedded in a solution of linear chains with various degrees of polymerization and concentrations. We distinguish the term “crowding”, addressing the impact of the polymer environment on the dendrimer, from the term “semidilute”, which refers to the state of the polymer environment only. Depending on the length of linear chains, two regimes are observed. Dendrimers in a solutio ...
DOI:
10.1021/acs.macromol.9b00010

4. Dispersive micro-solid phase extraction

Author:
Chisvert, Alberto; Cárdenas, Soledad; Lucena, Rafael
Source:
Trends in analytical chemistry 2019 v.112 pp. 226-233
ISSN:
0165-9936
Subject:
solvents,   etc   ; automation; sorbents; sorption;     Show all 4 Subjects
Abstract:
... Dispersive micro-solid phase extraction (D-μSPE) has gained special attention in the sample preparation process due to its simplicity, speed and efficiency. Different dispersion approaches have been used within this technique to allow a close contact between the sorbent and the donor sample solution during the entrapping step, but also between the sorbent and the solvent in the elution step. This ...
DOI:
10.1016/j.trac.2018.12.005

5. Quantification of azide groups on a material surface and a biomolecule using a clickable and cleavable fluorescent compound

Author:
Sakai, Rika; Iguchi, Hiroki; Maruyama, Tatsuo
Source:
RSC advances 2019 v.9 no.8 pp. 4621-4625
ISSN:
2046-2069
Subject:
solvents,   etc   ; azides; fluorescent dyes;     Show all 3 Subjects
Abstract:
... Here, we propose a novel method for quantifying azide groups on a solid surface and a protein using a clickable and cleavable fluorescent compound. The clickable and cleavable fluorescent compound conjugates with the azide groups on the material surface and the fluorophore is then liberated into the solvent via a cleavage reaction, which can be simply quantified with a conventional fluorometer. ...
DOI:
10.1039/c8ra09421g

6. Highly Enhanced Thermochromic Performance of VO₂ Film Using “Movable” Antireflective Coatings

Author:
Xu, Fang; Cao, Xun; Shao, Zewei; Sun, Guangyao; Long, Shiwei; Chang, Tianci; Luo, Hongjie; Jin, Ping
Source:
ACS applied materials & interfaces 2019 v.11 no.5 pp. 4712-4718
ISSN:
1944-8252
Subject:
solvents,   etc   ; coatings; electricity generation;     Show all 3 Subjects
Abstract:
... The VO₂ film with “movable” antireflective (AR) coating was initially designed and successfully prepared to deal with the challenges that VO₂ faced. The “movable” AR layer, including water and other organic solvents, not only endowed VO₂ with active-passive regulation mode but also dramatically enhanced the thermochromic performance. Furthermore, we combined solid and movable antireflection layer ...
DOI:
10.1021/acsami.8b20794

7. Guest-Dependent Dynamics in a 3D Covalent Organic Framework

Author:
Chen, Yichong; Shi, Zhao-Lin; Wei, Lei; Zhou, Beibei; Tan, Jing; Zhou, Hao-Long; Zhang, Yue-Biao
Source:
Journal of the American Chemical Society 2019 v.141 no.7 pp. 3298-3303
ISSN:
1520-5126
Subject:
solvents,   etc   ; geometry; molecular conformation;     Show all 3 Subjects
Abstract:
... Guest-dependent dynamics having both crystal contraction and expansion upon inclusion of various guests is uncovered in a 3D covalent organic framework (COF) prepared with a facile and scalable method. A molecular-level understanding of how the framework adjusts the node geometry and molecular configuration to perform significant contraction and large amplitude expansion are resolved through synch ...
DOI:
10.1021/jacs.8b13691

8. Catalytic α-Selective Deuteration of Styrene Derivatives

Author:
Puleo, Thomas R.; Strong, Alivia J.; Bandar, Jeffrey S.
Source:
Journal of the American Chemical Society 2019 v.141 no.4 pp. 1467-1472
ISSN:
1520-5126
Subject:
solvents,   etc   ; methanol; styrene;     Show all 3 Subjects
Abstract:
... We report an operationally simple protocol for the catalytic α-deuteration of styrenes. This process proceeds via the base-catalyzed reversible addition of methanol to styrenes in DMSO-d₆ solvent. The concentration of methanol is shown to be critical for high yields and selectivities over multiple competing side reactions. The synthetic utility of α-deuterated styrenes for accessing deuterium-labe ...
DOI:
10.1021/jacs.8b12874

9. Controlled addition of new liquid component into surface droplet arrays by solvent exchange

Author:
Li, Miaosi; Yu, Haitao; Bao, Lei; Dyett, Brendan; Zhang, Xuehua
Source:
Journal of colloid and interface science 2019 v.543 pp. 164-173
ISSN:
0021-9797
Subject:
solvents,   etc   ; droplets; liquids; mixing; prediction;     Show all 5 Subjects
Abstract:
... Microscopic droplets integrating multiple functionalities are essential in the microcompartmentalized related reaction and applications. Solvent exchange is a simple approach for producing femtoliter surface droplets by the transit oversaturation created at the mixing front of a solution by a poor solvent. But it remains challenging to control the compositions in nanodroplets. Our hypothesis is th ...
DOI:
10.1016/j.jcis.2019.02.046

10. Control over the synthesis of homovalent and mixed-valence cubic cobalt-imidazolate cages

Author:
LiangThese authors contributed equally to this work., Liang; Luo, Dong; Zuo, Tao; Zhou, Xiao-Ping; Li, Dan
Source:
Chemical communications 2019 v.55 no.35 pp. 5103-5106
ISSN:
1364-548X
Subject:
solvents,   etc   ; chemical compounds; chemical reactions;     Show all 3 Subjects
Abstract:
... A series of cubic cobalt-imidazolate cages have been successfully synthesized via subcomponent self-assembly in different solvents under solvothermal conditions. The homovalent Coᴵᴵ and mixed-valence Coᴵᴵᴵ,ᴵᴵ-imidazolate cages are assembled with control over the mixed solvent ratio of N,N-diethylformamide/ethanol, respectively. ...
DOI:
10.1039/c9cc02083g

11. Solvent and catalyst free synthesis of 3,4-dihydropyrimidin-2(1H)-ones/thiones by twin screw extrusion

Author:
Carvalho, Reyniel Ben; Joshi, Shreerang V.
Source:
Green chemistry 2019 v.21 no.8 pp. 1921-1924
ISSN:
1463-9270
Subject:
solvents,   etc   ; catalysts; extrusion; green chemistry;     Show all 4 Subjects
Abstract:
... This report describes the synthesis of a few 3,4-dihydropyrimidin-2(1H)-ones/thiones using a twin screw extruder. Use of the extruder allowed the reaction to be carried out without a catalyst or solvent. Twin screw extrusion can also be executed as a continuous process and is easy to scale up. ...
DOI:
10.1039/c9gc00036d

12. Constraint Release Mechanisms for H-Polymers Moving in Linear Matrices of Varying Molar Masses

Author:
Lentzakis, Helen; Costanzo, Salvatore; Vlassopoulos, Dimitris; Colby, Ralph H.; Read, Daniel Jon; Lee, Hyojoon; Chang, Taihyun; van Ruymbeke, Evelyne
Source:
Macromolecules 2019 v.52 no.8 pp. 3010-3028
ISSN:
1520-5835
Subject:
solvents,   etc   ; melting; molecular weight; viscoelasticity;     Show all 4 Subjects
Abstract:
... We investigate the influence of the environment on the relaxation dynamics of well-defined H-polymers diluted in a matrix of linear chains. The molar mass of the linear chain matrix is systematically varied and the relaxation dynamics of the H-polymer is probed by means of linear viscoelastic measurements, with the aim to understand its altered motion in different blends, compared to its pure melt ...
DOI:
10.1021/acs.macromol.9b00251

13. Ag-Catalyzed Chemoselective Decarboxylative Mono- and gem-Difluorination of Malonic Acid Derivatives

Author:
Wang, Zhen; Guo, Cong-Ying; Yang, Cheng; Chen, Jian-Ping
Source:
Journal of the American Chemical Society 2019 v.141 no.14 pp. 5617-5622
ISSN:
1520-5126
Subject:
solvents,   etc   ; chemoselectivity; malonic acid; moieties;     Show all 4 Subjects
Abstract:
... Malonic acid derivatives have been successfully applied in a Ag-catalyzed decarboxylative fluorination reaction, providing an unprecedented route to either gem-difluoroalkanes or α-fluorocarboxylic acids by the judicious selection of base and solvent. This reaction features the use of readily available starting materials, tunable chemoselectivity and good functional group compatibility as well as ...
DOI:
10.1021/jacs.9b00681

14. 1,2-Diazacyclopentane-3,5-diyl Diradicals: Electronic Structure and Reactivity

Author:
Yoshidomi, Shohei; Abe, Manabu
Source:
Journal of the American Chemical Society 2019 v.141 no.9 pp. 3920-3933
ISSN:
1520-5126
Subject:
solvents,   etc   ; homolytic cleavage; photolysis; temperature;     Show all 4 Subjects
Abstract:
... Localized singlet diradicals are key intermediates in bond homolysis. A thorough study of the reactive species is needed to clarify the mechanisms of the homolytic bond cleavage and formation processes. In general, the singlet diradicals are quite short-lived because of the fast radical–radical coupling reactions. The short-lived characteristic has retarded the thorough study on bond homolysis. In ...
DOI:
10.1021/jacs.8b12254

15. High-Speed, High-Efficiency Achiral SFC on a 3 × 20-mm Column Packed with 1.8-µm Particles Facilitated by a Low-Dispersion Chromatograph

Author:
Berger, Terry A.
Source:
Chromatographia 2019 v.82 no.2 pp. 537-542
ISSN:
0009-5893
Subject:
solvents,   etc   ; chromatography; methanol; silica; solutes;     Show all 5 Subjects
Abstract:
... There are almost no reports using 20–30 mm long (or shorter) columns packed with sub-2 µm packings for SFC separation of achiral solutes in the literature, probably because current commercial SFCs have extra-column dispersion of > 80 µL². A modified supercritical fluid chromatograph (SFC) with extra-column dispersion below 5 µL² produced reduced plate heights as low as 2.2, using a 3 × 20-mm colum ...
DOI:
10.1007/s10337-018-3655-5

16. Influence of thermal conductivity on photothermal lens spectroscopy

Author:
Liu, Mingqiang
Source:
Thermochimica acta 2019 v.672 pp. 126-132
ISSN:
0040-6031
Subject:
solvents,   etc   ; nanoparticles; spectroscopy; thermal conductivity;     Show all 4 Subjects
Abstract:
... Thermal conductivity (κ) is a key factor influencing the sensitivity of photothermal techniques. In thermal lens spectroscopy (TLS), photothermal signal was previously regarded as being proportional to 1/κ. Here, I show that the 1/κ dependence of photothermal signal is only valid on condition that the thermal diffusion length (LD) exceeds quintuple the excitation beam radius (ae) for an ensemble s ...
DOI:
10.1016/j.tca.2018.12.022

17. Gradient method transfer after changing the average pore diameter of the chromatographic stationary phase I – One-dimensional sample mixture

Author:
Gritti, Fabrice
Source:
Journal of chromatography 2019 v.1597 pp. 119-131
ISSN:
0021-9673
Subject:
solvents,   etc   ; chemistry; chromatography; models; prediction; thiourea;     Show all 6 Subjects
Abstract:
... Three different approaches designed to transfer gradient methods from a chromatographic column 1 packed with particles (2.7 μm 90 ÅCORTECS-C18 or CORTECS-Triphenyl) to a column 2 packed with the same particles having a larger average pore diameter (APD = 120 Åand 450 Å) are proposed for a one-dimensional sample mixture. Two approaches are based on the variation of the experimental retention plots ...
DOI:
10.1016/j.chroma.2019.03.024

18. Surface modification of TiO2 for the preparation of full-dull polyamide-6 polymers

Author:
Yang, Yu-ting; Yi, Chun-wang
Source:
Journal of materials science 2019 v.54 no.13 pp. 9456-9465
ISSN:
0022-2461
Subject:
solvents,   etc   ; liquids; polymers; temperature; titanium dioxide;     Show all 5 Subjects
Abstract:
... In this study, a novel surface modification approach for preparation of nanoscale titanium dioxide using aluminate coupling agent was developed. By optimizing the adding content of aluminate coupling agent and the reaction temperature, modified titanium dioxide (A-TiO₂) particles with a minimum Z-average size of 32 nm and a narrow PDI of 0.214 were obtained. Further tests revealed that A-TiO₂ was ...
DOI:
10.1007/s10853-019-03549-x

19. Facile preparation of polyacrylonitrile-co-methylacrylate based integrally skinned asymmetric nanofiltration membranes for sustainable molecular separation: An one-step method

Author:
Xu, Yanchao; Tognia, Meudjeu; Guo, Dongxue; Shen, Liguo; Li, Renjie; Lin, Hongjun
Source:
Journal of colloid and interface science 2019 v.546 pp. 251-261
ISSN:
0021-9797
Subject:
solvents,   etc   ; dioxane; methyl orange; nanofiltration; polyacrylonitrile; ultrafiltration;     Show all 6 Subjects
Abstract:
... While polyacrylonitrile (PAN) has been widely used to prepare membranes, it is still not handy to prepare PAN integrally skinned asymmetric (ISA) nanofiltration (NF) membrane via direct immersion precipitation phase inversion method. Herein, a low-cost and commercial polyacrylonitrile-co-methylacrylate, P(AN-co-MA), was demonstrated to prepare ISA NF membranes via a one-step immersion precipitatio ...
DOI:
10.1016/j.jcis.2019.03.067

20. pH-sensitive fluorescent organic nanoparticles: Off-on fluorescent detection of furfural in transformer oil

Author:
Chang, Chao; Han, Lei; Zhao, Yanfang; Li, Feng
Source:
Talanta 2019 v.197 pp. 383-389
ISSN:
0039-9140
Subject:
solvents,   etc   ; fluorescence; furfural; hydroxylamine; nanoparticles; oils; protons;     Show all 7 Subjects
Abstract:
... Furfural content is considered as index to estimate transformer remnant life. Therefore, low cost, highly sensitive methods for determination of furfural are highly desirable. In the present work, we describe a new strategy for furfural detection by tracing the “off-on” fluorescence signals of fluorescent organic nanoparticles (FONPs). Significant H+-dependent emission characteristics in aprotic o ...
DOI:
10.1016/j.talanta.2019.01.053