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1. Ambient volatile organic compounds at a receptor site in the Pearl River Delta region: Variations, source apportionment and effects on ozone formation

Author:
Meng, Yao; Song, Junwei; Zeng, Lewei; Zhang, Yingyi; Zhao, Yan; Liu, Xufei; Guo, Hai; Zhong, Liuju; Ou, Yubo; Zhou, Yan; Zhang, Tao; Yue, Dingli; Lai, Senchao
Source:
Journal of environmental sciences (China) 2022 v.111 pp. 104-117
ISSN:
1001-0742
Subject:
solvents,   etc   ; air; aromatic compounds; diurnal variation; evaporation; gasoline; models; ozone; pollution; river deltas; rivers; volatile organic compounds; China;     Show all 13 Subjects
Abstract:
... We present the continuously measurements of volatile organic compounds (VOCs) at a receptor site (Wan Qing Sha, WQS) in the Pearl River Delta (PRD) region from September to November of 2017. The average mixing ratios of total VOCs (TVOCs) was 36.3 ± 27.9 ppbv with the dominant contribution from alkanes (55.5%), followed by aromatics (33.3%). The diurnal variation of TVOCs showed a strong photochem ...
DOI:
10.1016/j.jes.2021.02.024

2. Spin diffusion transfer difference (SDTD) NMR: An advanced method for the characterisation of water structuration within particle networks

Author:
Gabrielli, Valeria; Kuraite, Agne; da Silva, Marcelo Alves; Edler, Karen J.; Angulo, Jesús; Nepravishta, Ridvan; Muñoz–García, Juan C.; Khimyak, Yaroslav Z.
Source:
Journal of colloid and interface science 2021 v.594 pp. 217-227
ISSN:
0021-9797
Subject:
solvents,   etc   ; equations; starch;     Show all 3 Subjects
Abstract:
... The classical STD NMR protocol to monitor solvent interactions in gels is strongly dependent on gelator and solvent concentrations and does not report on the degree of structuration of the solvent at the particle/solvent interface. We hypothesised that, for suspensions of large gelator particles, solvent structuration could be characterised by STD NMR when taking into account the particle-to-solve ...
DOI:
10.1016/j.jcis.2021.02.094

3. Differentiating bulk nanobubbles from nanodroplets and nanoparticles

Author:
Eklund, Fredrik; Alheshibri, Muidh; Swenson, Jan
Source:
Current opinion in colloid & interface science 2021 v.53 pp. 101427
ISSN:
1359-0294
Subject:
solvents,   etc   ; nanobubbles; ultrasonics;     Show all 3 Subjects
Abstract:
... History has shown that it is not as easy as one might think to differentiate between bulk nanobubbles and nanodroplets or nanoparticles. It is generally easy to detect colloids (i.e. something that looks different, e.g. scatters light differently than its surrounding solvent), but less easy to determine the nature of these colloids. This has led to misinterpretations in the literature, where nanod ...
DOI:
10.1016/j.cocis.2021.101427

4. Separation and recovery of cobalt and nickel from end of life products via solvent extraction technique: A review

Author:
Alvial-Hein, Guillermo; Mahandra, Harshit; Ghahreman, Ahmad
Source:
Journal of cleaner production 2021 v.297 pp. 126592
ISSN:
0959-6526
Subject:
solvents,   etc   ; cobalt; nickel;     Show all 3 Subjects
Abstract:
... The significant development in advanced technologies such as lithium-ion batteries has increased the demand of cobalt and nickel. As a result, continuous supply from primary resources leads cobalt to the critical stage and also affects nickel resources extensively. The presence of limited resources can lead to break in the chain of supply of these metals on demand. Therefore, it is necessary to re ...
DOI:
10.1016/j.jclepro.2021.126592

5. Site-Specific Oxidation of (sp³)C–C(sp³)/H Bonds by NaNO₂/HCl

Author:
Zhao, Jianyou; Shen, Tong; Sun, Zhihui; Wang, Nengyong; Yang, Le; Wu, Jintao; You, Huichao; Liu, Zhong-Quan
Source:
Organic letters 2021 v.23 no.10 pp. 4057-4061
ISSN:
1523-7052
Subject:
solvents,   etc   ; organic chemistry; oxidation;     Show all 3 Subjects
Abstract:
... A site-specific oxidation of (sp³)C–C(sp³) and (sp³)C–H bonds in aryl alkanes by the use of NaNO₂/HCl was explored. The method is chemical-oxidant-free, transition-metal-free, uses water as the solvent, and proceeds under mild conditions, making it valuable and attractive to synthetic organic chemistry. ...
DOI:
10.1021/acs.orglett.1c01303

6. Mechanistically Guided Design of an Efficient and Enantioselective Aminocatalytic α-Chlorination of Aldehydes

Author:
Hutchinson, George; Alamillo-Ferrer, Carla; Burés, Jordi
Source:
Journal of the American Chemical Society 2021 v.143 no.18 pp. 6805-6809
ISSN:
1520-5126
Subject:
solvents,   etc   ; catalysts; enantioselectivity;     Show all 3 Subjects
Abstract:
... The enantioselective aminocatalytic α-chlorination of aldehydes is a challenging reaction because of its tendency to proceed through neutral intermediates in unselective pathways. Herein we report the rational shift to a highly selective reaction pathway involving charged intermediates using hexafluoroisopropanol as solvent. This change in mechanism has enabled us to match and improve upon the yie ...
DOI:
10.1021/jacs.1c02997

7. Dual-state efficient chromophore with pH-responsive and solvatofluorochromic properties based on an asymmetric single benzene framework

Author:
Liu, Huijing; Zhang, Sisi; Ding, Liping; Fang, Yu
Source:
Chemical communications 2021 v.57 no.33 pp. 4011-4014
ISSN:
1364-548X
Subject:
solvents,   etc   ; benzene; fluorescence; pH;     Show all 4 Subjects
Abstract:
... We present a unique single-benzene-based chromophore with asymmetric structure that emits efficient luminescence in both solid and solution states and shows solvatofluorochromism, large Stokes shift (154–219 nm) and an extraordinary wide range of solvent compatibility. The asymmetric structural feature endows this chromophore with significant ratiometric pH-dependent fluorescence for accurate and ...
DOI:
10.1039/d1cc00718a

8. Solvent and catalyst-free bromofunctionalization of olefins using a mechanochemical approach

Author:
Wong, Jonathan; Yeung, Ying-Yeung
Source:
RSC advances 2021 v.11 no.22 pp. 13564-13570
ISSN:
2046-2069
Subject:
solvents,   etc   ; forces; mechanochemistry;     Show all 3 Subjects
Abstract:
... Bromofunctionalizations of olefins are an important class of chemical transformations. N-Bromoimide reagents are commonly used in these reactions but catalysts and chlorinated solvents are often employed to achieve a reasonable reaction rate. In this report, we present a solvent and catalyst-free bromofunctionalization of olefins using mechanical force. ...
DOI:
10.1039/d1ra01816g

9. Reverse synthesis of yolk–shell metal–organic frameworks

Author:
Zhang, Songwei; Fan, Yaqi; Luo, Lianshun; Li, Conger; Ma, Yanhang; Li, Tao
Source:
Chemical communications 2021 v.57 no.27 pp. 3415-3418
ISSN:
1364-548X
Subject:
solvents,   etc   ; coordination polymers; crystallization;     Show all 3 Subjects
Abstract:
... We report the first examples of yolk–shell metal–organic framework (MOF) heterostructures based on topologically distinct MOFs: ZIF-8/ZIF-67 and UiO-66. This was accomplished through an innovative reverse synthesis strategy: A hollow UiO-66 was first constructed; the precusors of the ZIFs were then loaded into the cavity of hollow UiO-66 through a mixed solvent impregnation method; subsequent crys ...
DOI:
10.1039/d1cc00548k

10. Solvent accommodation effect on dispersibility of metal oxide nanoparticle with chemisorbed organic shell

Author:
Tomai, Takaaki; Tajima, Naoya; Kimura, Motoyuki; Yoko, Akira; Seong, Gimyeong; Adschiri, Tadafumi
Source:
Journal of colloid and interface science 2021 v.587 pp. 574-580
ISSN:
0021-9797
Subject:
solvents,   etc   ; dispersibility; molecular weight;     Show all 3 Subjects
Abstract:
... The dispersibility of nanoparticles in solvents remains difficult to predict and control. In this paper, the dispersibility of organically-modified nanoparticles in various solvents with different solvent properties and molecular sizes are investigated. The study indicates that solvent molecular size, in addition to the affinity between organic modifier and solvent molecules, affects the dispersib ...
DOI:
10.1016/j.jcis.2020.11.014

11. Binary non-fullerene-based polymer solar cells with a 430 nm thick active layer showing 15.39% efficiency and 73.38% fill factor

Author:
Pan, Feilong; Luo, Mei; Liu, Xuncheng; Jiang, Haiying; Wang, Zhen; Yuan, Dong; Wang, Qian; Qing, Lechi; Zhang, Zesheng; Zhang, Lianjie; Zou, Yingping; Chen, Junwu
Source:
Journal of materials chemistry A 2021 v.9 no.11 pp. 7129-7136
ISSN:
2050-7496
Subject:
solvents,   etc   ; chemistry; polymers; xylene;     Show all 4 Subjects
Abstract:
... Thickness-sensitive fill factor (FF) is usually encountered by organic active layers with a thickness of several hundred nanometers, which significantly deteriorate the photovoltaic performance of thick-film polymer solar cells (PSCs). Here, paring of high-hole mobility (μₕ) polymer donor Si25 with benzotriazole-fused Y-series non-fullerene acceptor Y14 is proposed to overcome this challenge. Rela ...
DOI:
10.1039/d1ta00287b

12. Insights into iodoplumbate complex evolution of precursor solutions for perovskite solar cells: from aging to degradation

Author:
Li, Bo; Dai, Qilin; Yun, Sining; Tian, Jianjun
Source:
Journal of materials chemistry A 2021 v.9 no.11 pp. 6732-6748
ISSN:
2050-7496
Subject:
solvents,   etc   ; crystallization; humidity;     Show all 3 Subjects
Abstract:
... The power conversion efficiency (PCE) of solution-processed perovskite solar cells (PSCs) is significantly influenced by the characteristics of the perovskite precursor solutions. Iodoplumbate complexes such as PbI₂, PbI₃⁻, and PbI₄²⁻ present in perovskite precursor solution in equilibria dictate the quality of perovskite films and the corresponding optoelectrical performance of PSCs. Meanwhile, t ...
DOI:
10.1039/d0ta12094d

13. Fine-tuning of the optical output in a dual responsive catenane switch

Author:
Deng, Yulin; Lai, Samuel Kin-Man; Kong, Linghui; Au-Yeung, Ho Yu
Source:
Chemical communications 2021 v.57 no.23 pp. 2931-2934
ISSN:
1364-548X
Subject:
solvents,   etc   ; catenanes; cations;     Show all 3 Subjects
Abstract:
... A [2]catenane switch where the intramolecular pyrene excimer emission can be controlled by orthogonal cation binding and solvent polarity change in various amplitudes and dynamic ranges is reported. ...
DOI:
10.1039/d1cc00310k

14. A green metal-free “one-pot” microwave assisted synthesis of 1,4-dihydrochromene triazoles

Author:
Alves, Tânia M. F.; Jardim, Guilherme A. M.; Ferreira, Marco A. B.
Source:
RSC advances 2021 v.11 no.17 pp. 10336-10339
ISSN:
2046-2069
Subject:
solvents,   etc   ; microwave radiation; triazoles;     Show all 3 Subjects
Abstract:
... The synthesis of several 4-aryl-1,4-dihydrochromene-triazoles was achieved via a metal-free “one-pot” procedure using PEG400 as the sole solvent in an eco-friendly process. Using microwave irradiation, the triazole derivatives were obtained in good yields and short reaction times starting from readily accessible building blocks. ...
DOI:
10.1039/d1ra01169c

15. A General Method for the Dibromination of Vicinal sp³ C–H Bonds Exploiting Weak Solvent–Substrate Noncovalent Interactions

Author:
Qi, Zaojuan; Li, Weihe; Niu, Yanning; Benassi, Enrico; Qian, Bo
Source:
Organic letters 2021 v.23 no.7 pp. 2399-2404
ISSN:
1523-7052
Subject:
solvents,   etc   ; ethane; quantum mechanics;     Show all 3 Subjects
Abstract:
... A general procedure of 1,2-dibromination of vicinal sp³ C–H bonds of arylethanes using N-bromosuccinimide as the bromide reagent without an external initiator has been established. The modulation of the strength of the intermolecular noncovalent interactions between the solvent and arylethane ethanes, quantitatively evaluated via quantum chemical calculations, allows us to circumvent the fact that ...
DOI:
10.1021/acs.orglett.0c04235

16. Singlet Fission in a Flexible Bichromophore with Structural and Dynamic Control

Author:
Aster, Alexander; Zinna, Francesco; Rumble, Christopher; Lacour, Jérôme; Vauthey, Eric
Source:
Journal of the American Chemical Society 2021 v.143 no.5 pp. 2361-2371
ISSN:
1520-5126
Subject:
solvents,   etc   ; cations; viscosity; wavelengths;     Show all 4 Subjects
Abstract:
... Singlet fission (SF), i.e., the splitting of a high-energy exciton into two lower-energy triplet excitons, has the potential to increase the efficiency for harvesting spectrally broad light. The path from the photopopulated singlet state to free triplets is complicated by competing processes that decrease the overall SF efficiency. A detailed understanding of the whole cascade and the nature of th ...
DOI:
10.1021/jacs.0c12384

17. [1,3]-Claisen Rearrangement via Removable Functional Group Mediated Radical Stabilization

Author:
Alam, Md Nirshad; Dash, Soumya Ranjan; Mukherjee, Anirban; Pandole, Satish; Marelli, Udaya Kiran; Vanka, Kumar; Maity, Pradip
Source:
Organic letters 2021 v.23 no.3 pp. 890-895
ISSN:
1523-7052
Subject:
solvents,   etc   ; derivatization; enols;     Show all 3 Subjects
Abstract:
... A thermal O-to-C [1,3]-rearrangement of α-hydroxy acid derived enol ethers was achieved under mild conditions. The 2-aminothiophenol protection of carboxylic acids facilitates formation of the [1,3] precursor and its thermal rearrangement via stabilization of a radical intermediate. Experimental and theoretical evidence for dissociative radical pair formation, its captodative stability via aminoth ...
DOI:
10.1021/acs.orglett.0c04109

18. Microfiber aligned hollow fiber membranes from immiscible polymer solutions by phase inversion

Author:
Jung, Jun Tae; Wang, Ho Hyun; Kim, Jeong F.; Jeon, Seong Min; Park, Sang Hyun; Lee, Won Hee; Moon, Sun Ju; Drioli, Enrico; Lee, Young Moo
Source:
Journal of membrane science 2021 v.617 pp. 118654
ISSN:
0376-7388
Subject:
solvents,   etc   ; fluorides; separation;     Show all 3 Subjects
Abstract:
... In this study, we report for the first time a pioneering method to prepare membranes with a fibrous morphology via phase inversion with extremely high pore connectivity. Microfiber aligned hollow fiber membranes were prepared via a polymer blend solution consisting of poly (vinylidene fluoride) with polysulfone in PolarClean® as a green solvent. The microfiber structure appeared only when controll ...
DOI:
10.1016/j.memsci.2020.118654

19. Theoretical study of twin-column recycling chromatography with a solvent-gradient for preparative binary separations

Author:
Wei, Feng; Sang, Jiarong; Zhao, Yingxian
Source:
Journal of chromatography 2021 v.1651 pp. 462306
ISSN:
0021-9673
Subject:
solvents,   etc   ; chromatography; models; sorption isotherms;     Show all 4 Subjects
Abstract:
... Twin-column recycling chromatography with a solvent gradient (TCRC-SG) was investigated with the equilibrium-dispersive chromatography model. The solvent gradient caused by constant addition of a modifier between the two columns created a band compression effect to counterbalance band broadening, so that the target component band neither broadened nor shrunk. Meanwhile, band compression accelerate ...
DOI:
10.1016/j.chroma.2021.462306

20. Drop Spreading and Confinement in Swelling-Driven Folding of Thin Films

Author:
Breid, Derek; Lai, Victoria; Flowers, Andrew T.; Guan, Xianheng; Liu, Qihan; Velankar, Sachin S.
Source:
Langmuir 2021 v.37 no.23 pp. 6985-6994
ISSN:
1520-5827
Subject:
solvents,   etc   ; delamination; mechanics; microstructure; models;     Show all 5 Subjects
Abstract:
... Surface instabilities are a versatile method for generating three-dimensional (3D) surface microstructure. When an elastomeric film weakly bonded to a substrate is swollen with solvent, buckle delamination and subsequent sliding of the film on the substrate lead to the formation of tall, self-contacting, and permanent folds. This paper explores the mechanics of fold development when such folding i ...
DOI:
10.1021/acs.langmuir.1c00520