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1. Improved utilization of active sites for phosphorus adsorption in FeOOH/anion exchanger nanocomposites via a glycol-solvothermal synthesis strategy

Author:
Zhang, Yi; Tang, Qiong; Sun, Yifan; Yao, Chenxu; Yang, Zhen; Yang, Weiben
Source:
Journal of environmental sciences (China) 2022 v.111 pp. 313-323
ISSN:
1001-0742
Subject:
phosphates,   etc   ; adsorbents; adsorption; nanocomposites; nanocrystals; phosphorus; quaternary ammonium compounds; risk; China;     Show all 9 Subjects
Abstract:
... Metal oxide/hydroxide-based nanocomposite adsorbents with porous supporting matrices have been recognized as efficient adsorbents for phosphorus recovery. Aiming at satisfying increasingly restrictive environmental requirements involving improving metal site utilization and lowering metal leakage risk, a glycol-solvothermal confined-space synthesis strategy was proposed for the fabrication of FeOO ...
DOI:
10.1016/j.jes.2021.04.018

2. Biomimetic fabrication and application of fibrous-like nanotubes

Author:
Zhang, Ling; Xu, Yuedan; Jin, Xinyang; Wang, Chaoyang; Li, Mingxing; Zhou, Zihuai; Fu, Baiping
Source:
Life sciences 2021 v.270 pp. 119126
ISSN:
0024-3205
Subject:
calcium phosphates,   etc   ; biomimetics; nanotubes;     Show all 3 Subjects
Abstract:
... To investigate the biomimetic fabrication of fibrous-like organic-inorganic hybrid structures via a simple bottom-up approach, viz. self-assembly of simple molecules, and apply fibrous-like composites as a novel primer to improve dentin bond strengths of self-etch adhesives.The resultants of commercial amorphous calcium phosphate (ACP) nanoparticles and 10-methacryloyloxydecyl dihydrogen phosphate ...
DOI:
10.1016/j.lfs.2021.119126

3. Catalytic Asymmetric C-7 Friedel–Crafts Alkylation/N-Hemiacetalization of 4-Aminoindoles

Author:
He, Hualing; Cao, Yang; Xu, Jun; Antilla, Jon C.
Source:
Organic letters 2021 v.23 no.8 pp. 3010-3014
ISSN:
1523-7052
Subject:
phosphates,   etc   ; catalysts; indoles; magnesium;     Show all 4 Subjects
Abstract:
... A unique catalytic asymmetric C-7 Friedel–Crafts alkylation/N-hemiacetalization cascade reaction of 4-aminoindoles with β,γ-unsaturated α-keto esters has been described. Using a chiral magnesium H₈–BINOL-derived bis(phosphate) complex as catalyst, the resulting functionalized 1,7-annulated indole scaffolds are obtained in high yields (up to 98%) and with good to excellent enantioselectivities (up ...
DOI:
10.1021/acs.orglett.1c00699

4. Carbazole sulfonamide-based macrocyclic receptors capable of selective complexation of fluoride ion

Author:
Luo, Na; Li, Junhong; Sun, Tao; Wan, Suran; Li, Peijia; Wu, Nan; Yan, Ya; Bao, Xiaoping
Source:
RSC advances 2021 v.11 no.17 pp. 10203-10211
ISSN:
2046-2069
Subject:
phosphates,   etc   ; acetates; acetonitrile; fluorides;     Show all 4 Subjects
Abstract:
... Two carbazole sulfonamide-based macrocycles 1 and 2 were facilely synthesized and carefully evaluated for their anion recognition properties. The obtained results revealed that macrocycle 1 with a 1,3-xylyl linker was able to bind fluoride ion more strongly and selectively in acetonitrile medium than its strong competitors (like acetate and dihydrogen phosphate anions), with a large binding consta ...
DOI:
10.1039/d1ra01285a

5. Two methods for the preparation of sitagliptin phosphate via chemical resolution and asymmetric hydrogenation

Author:
Ye, Fei; Zhang, Zhifeng; Zhao, Wenxia; Ding, Jianhai; Wang, Yali; Dang, Xueyan
Source:
RSC advances 2021 v.11 no.8 pp. 4805-4809
ISSN:
2046-2069
Subject:
phosphates,   etc   ; enamines; hydrogenation;     Show all 3 Subjects
Abstract:
... Two effective processes have been developed for the preparation of sitagliptin phosphate. The approach of chemical resolution obtained R-sitagliptin in five steps from commercially available starting materials using the inexpensive NaBH₄ to reduce the enamine and then using (−)-di-p-toluoyl-l-tartaric acid to resolve racemates in 11% yield overall. The route successfully avoids the use of expensiv ...
DOI:
10.1039/d0ra10273c

6. Competitive arsenate and phosphate adsorption on α-FeOOH, LaOOH, and nano-TiO2: Two-dimensional correlation spectroscopy study

Author:
Li, Xiaochen; Yan, Li; Zhong, Wen; Kersten, Michael; Jing, Chuanyong
Source:
Journal of hazardous materials 2021 v.414 pp. 125512
ISSN:
0304-3894
Subject:
phosphates,   etc   ; adsorbents; adsorption; arsenates; calcium;     Show all 5 Subjects
Abstract:
... Competitive adsorption of arsenate (AsO₄³⁻) and phosphate (PO₄³⁻) on α-FeOOH, LaOOH, and nano-TiO₂ was studied using batch adsorption experiments and in-situ flow cell ATR-FTIR coupled with two-dimensional correlation spectroscopy (2D-COS) for the first time. With a higher temporal resolution, our results found a highly dynamic adsorption sequence for AsO₄³⁻ and PO₄³⁻. When AsO₄³⁻ and PO₄³⁻ were s ...
DOI:
10.1016/j.jhazmat.2021.125512

7. Determination of individual oligonucleotide impurities by small amine ion pair-RP HPLC MS and MS/MS: n − 1 impurities

Author:
Roussis, Stilianos G.; Rodriguez, Andrew A.; Rentel, Claus
Source:
Journal of chromatography 2021 v.1169 pp. 122611
ISSN:
1570-0232
Subject:
phosphates,   etc   ; ammonium bicarbonate; esters; oligonucleotides;     Show all 4 Subjects
Abstract:
... Ion pair-reversed phase (IP-RP) HPLC is one of the most widely used methods for the analysis of oligonucleotide impurities. The method is compatible with mass spectrometry and has been used to guide the development of improved synthesis and purification approaches. The ability to detect and characterize impurities depends on the reagents and the IP buffer system employed, as each can directly affe ...
DOI:
10.1016/j.jchromb.2021.122611

8. A fully integrated isotachophoresis with a programmable microfluidic platform

Author:
Shebindu, Adam; Somaweera, Himali; Estlack, Zachary; Kim, Jungtae; Kim, Jungkyu
Source:
Talanta 2021 v.225 pp. 122039
ISSN:
0039-9140
Subject:
phosphates,   etc   ; borates; buffers; microfluidic technology;     Show all 4 Subjects
Abstract:
... Conventional isotachophoresis (ITP) can be used for pre-concentration of a single analyte, but preconcentration of multiple analytes is time consuming due to handling and washing steps required for the extensive buffer optimization procedure. In this work, we present a programmable microfluidic platform (PMP) to demonstrate fully automated optimization of ITP of multiple analytes. By interfacing a ...
DOI:
10.1016/j.talanta.2020.122039

9. Highly regenerative and efficient adsorption of phosphate by restructuring natural palygorskite clay via alkaline activation and co-calcination

Author:
Wei, Yanfu; Guo, Kexin; Wu, Honghai; Yuan, Peng; Liu, Dong; Du, Peixin; Chen, Pengcheng; Wei, Longmeng; Chen, Wei
Source:
Chemical communications 2021 v.57 no.13 pp. 1639-1642
ISSN:
1364-548X
Subject:
phosphates,   etc   ; adsorbents; adsorption; clay; palygorskite;     Show all 5 Subjects
Abstract:
... Herein, we present a new strategy to create a highly regenerative and efficient phosphate adsorbent based on activating natural palygorskite structures. Both the regeneration via alkaline activation and synthesis via co-calcination restructured the palygorskite and created adsorptive metal oxides. The phosphate adsorbent exhibits excellent regeneration performance with high removal capacity. ...
DOI:
10.1039/d0cc07888c

10. Objective functions from Bayesian optimization to locate additional drillholes

Author:
Jafrasteh, Bahram; Suárez, Alberto
Source:
Computers & geosciences 2021 v.147 pp. 104674
ISSN:
0098-3004
Subject:
phosphates,   etc   ; Bayesian theory; expert opinion;     Show all 3 Subjects
Abstract:
... The key available information to choose new locations for drilling are the estimated ore grade values and the corresponding uncertainties at the tentative locations. These pieces of information are combined to generate a single objective function. The mathematical form of the objective function should reflect the effect of these values and their relative importance. Traditional objective function ...
DOI:
10.1016/j.cageo.2020.104674

11. Understanding the effect of oxide components on proton mobility in phosphate glasses using a statical analysis approach

Author:
Omata, Takahisa; Suzuki, Issei; Sharma, Aman; Ishiyama, Tomohiro; Nishii, Junji; Yamashita, Toshiharu; Kawazoe, Hiroshi
Source:
RSC advances 2021 v.11 no.5 pp. 3012-3019
ISSN:
2046-2069
Subject:
phosphates,   etc   ; glass; glass transition temperature;     Show all 3 Subjects
Abstract:
... The models to describe the proton mobility (μH) together with the glass transition temperature (Tg) of proton conducting phosphate glasses employing the glass composition as descriptors have been developed using a statical analysis approach. According to the models, the effects of additional HO₁/₂, MgO, BaO, LaO₃/₂, WO₃, NbO₅/₂, BO₃/₂ and GeO₂ as alternative to PO₅/₂ were found as following. μH at ...
DOI:
10.1039/d0ra10327f

12. Metal ion-triggered Pickering emulsions and foams for efficient metal ion extraction

Author:
Huang, Zhaohui; Sun, Xiuping; Liu, Yihan; Cui, Jiwei; Song, Aixin; Hao, Jingcheng
Source:
Journal of colloid and interface science 2021 v.602 pp. 187-196
ISSN:
0021-9797
Subject:
phosphates,   etc   ; air; anionic surfactants; industrial wastewater; oils;     Show all 5 Subjects
Abstract:
... Emulsions and foams were constructed by using surfactant particles as stabilizers. Bis(2-ethylhexyl) phosphate, abbreviated as HDEHP, was used as both an oil in neutral form and an anionic surfactant in deprotonated form, DEHP⁻. In the system of HDEHP/H₂O, upon adding NaOH, a portion of HDEHP was deprotonated to form DEHP⁻ as stabilizers of O/W emulsions. After introducing some certain metal ions, ...
DOI:
10.1016/j.jcis.2021.05.182

13. Calcium phosphate scaling in osmotically driven membrane processes: Limiting flux behavior and its implications for scaling mitigation

Author:
Fei, Jingyuan; Lyu, You; Zhong, Xia; Wiley, Dianne E.; Liu, Zongwen; She, Qianhong
Source:
Journal of membrane science 2021 v.631 pp. 119351
ISSN:
0376-7388
Subject:
calcium phosphates,   etc   ; calcium; crystallization; osmosis; pH;     Show all 5 Subjects
Abstract:
... Calcium phosphate scaling, a typical inorganic scaling, has been identified as a challenging issue in the operation of osmotically driven membrane processes (ODMPs) especially in pressure-retarded osmosis (PRO) mode where membrane porous substrate faces against the impaired feed solution (FS). During scaling in PRO mode, it has been observed that flux declines to a pseudo-stable level - limiting f ...
DOI:
10.1016/j.memsci.2021.119351

14. PTH resistance

Author:
Mantovani, Giovanna; Elli, Francesca Marta
Source:
Molecular and cellular endocrinology 2021 v.531 pp. 111311
ISSN:
0303-7207
Subject:
phosphates,   etc   ; calcium; homeostasis; hyperparathyroidism; hypoparathyroidism; parathyroid hormone;     Show all 6 Subjects
Abstract:
... Parathyroid hormone (PTH), which is primarily regulated by extracellular calcium changes, controls calcium and phosphate homeostasis. Different diseases are derived from PTH deficiency (hypoparathyroidism), excess (hyperparathyroidism) and resistance (pseudohypoparathyroidism, PHP). Pseudohypoparathyroidism was historically classified into subtypes according to the presence or not of inherited PTH ...
DOI:
10.1016/j.mce.2021.111311

15. Antimicrobial effectiveness of beverage containers made of silver doped PET

Author:
Braun, Sabrina; Ilberg, Vladimir; Langowski, Horst-Christian
Source:
Journal of food engineering 2021 v.300 pp. 110526
ISSN:
0260-8774
Subject:
phosphates,   etc   ; Escherichia coli; glass; iced tea; silver;     Show all 5 Subjects
Abstract:
... Active packaging based on a release of silver ions (Ag⁺) has become a focus of increasing interest. However, applications are rare for beverages in particular, and the question remains whether the amount for antimicrobial effectiveness is below the migration limit of 0.05 mg Ag/kg food proposed by the EFSA. Experiments were performed using E. coli (10⁶ cfu/mL) in distilled water and Z. bailii (<10 ...
DOI:
10.1016/j.jfoodeng.2021.110526

16. Sustainable and green synthesis of 3-methyl-4-arylmethylene-isoxazole-5(4H)-one derivatives under mild conditions using a novel phosphoric acid-based molten salt as catalyst

Author:
Asadi, Shaghayegh Khedmatgozar; Aleaba, Gilda; Daneshvar, Nader; Shirini, Farhad
Source:
Sustainable chemistry and pharmacy 2021 v.21 pp. 100442
ISSN:
2352-5541
Subject:
phosphates,   etc   ; catalysts; cost effectiveness; green chemistry; solvents;     Show all 5 Subjects
Abstract:
... In this work, pyrrolidinium dihydrogen phosphate ([H-Pyrr][H₂PO₄]) was prepared as a novel green molten salt from cheap and commercially available starting materials with a very simple method and identified by various methods including FT-IR and NMR techniques. In continue, this reagent was used as a recyclable and effective catalyst in the synthesis of bioactive potent 3-methyl-4-arylmethylene-iz ...
DOI:
10.1016/j.scp.2021.100442

17. Synthesis of difluoromethylated diarylmethanes via Fe(OTf)₃-catalyzed Friedel–Crafts reaction of 2,2-difluoro-1-arylethyl phosphates

Author:
Yamamoto, Yoshihiko; Takase, Tomoya; Kuroyanagi, Eisuke; Yasui, Takeshi
Source:
Chemical communications 2021 v.57 no.32 pp. 3877-3880
ISSN:
1364-548X
Subject:
phosphates,   etc   ; Lewis acids; aromatic hydrocarbons; chemical reactions;     Show all 4 Subjects
Abstract:
... The Fe(OTf)₃-catalyzed Friedel–Crafts reaction of 2,2-difluoro-1-arylethyl phosphates with electron-rich (hetero)arenes afforded difluoromethylated diarylmethanes. Control experiments showed that Fe(OTf)₃ behaves as the Lewis acid, and that the phosphate leaving group and o- or p-alkoxy substituents on the substrates are necessary for the Fe(OTf)₃-catalyzed reaction to proceed under mild condition ...
DOI:
10.1039/d1cc00765c

18. The use of phosphate minerals for determination of the provenance of flint used by prehistoric communities in East-Central Europe

Author:
Werra, Dagmara H.; Siuda, Rafał
Source:
Quaternary international 2021
ISSN:
1040-6182
Subject:
phosphates,   etc   ; chemical composition; provenance; Poland; Ukraine;     Show all 5 Subjects
Abstract:
... The area of the Vistula is rich in deposits of several kinds of flint that were widely used in prehistoric times: ‘chocolate’, grey white-spotted, Jurassic-Kraków, striped (banded), and on its eastern borders, Volhynian. The differentiation of these flint types and determination of their characteristic features can be achieved by applying mineralogical studies. Samples of flint from Poland and Ukr ...
DOI:
10.1016/j.quaint.2021.04.028

19. Network-Forming Units, Energy Landscapes, and Conductivity Activation Energies in Alkali Borophosphate Glasses: Analytical Approaches

Author:
Bosi, Marco; Fischer, Julian; Maass, Philipp
Source:
Journal of physical chemistry 2021 v.125 no.11 pp. 6260-6268
ISSN:
1932-7455
Subject:
phosphates,   etc   ; borates; glass; landscapes; physical chemistry;     Show all 5 Subjects
Abstract:
... A major challenge in the modeling of ionically conducting glasses is to understand how the large variety of possible chemical compositions and specific features of their structure influence ionic transport quantities. Here we revisit and extend a theoretical approach for alkali borophosphate glasses, where changes of conductivity activation energies with the borate to phosphate mixing ratio are re ...
DOI:
10.1021/acs.jpcc.0c09960

20. Custom pyrolyzer for the pyrolysis of chemical warfare agents

Author:
Van Buren, Daniel J.; Mueller, Thomas J.; Rosenker, Christopher J.; Barcase, John A.; Van Houten, Kelly A.
Source:
Journal of analytical and applied pyrolysis 2021 v.154 pp. 105007
ISSN:
0165-2370
Subject:
phosphates,   etc   ; activation energy; desorption; pyrolysis; sorbents;     Show all 5 Subjects
Abstract:
... Thermal decomposition studies on a chemical warfare agent (CWA) simulant was performed using a custom built pyrolyzer. The goals of this study were to design, build and evaluate a simple pyrolyzer to meet the safety and security requirements necessary to obtain consistent CWA and CWA simulant pyrolysis data from multiple laboratories around the world. A custom made tubular flow reactor was built, ...
DOI:
10.1016/j.jaap.2020.105007