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1. Factors that determine thione(thiol)–disulfide interconversion in a bis(thiosemicarbazone) copper(ii) complex

Author:
Jeong, Haewon; Kang, Yeji; Kim, Jin; Kim, Byung-Kwon; Hong, Seungwoo
Source:
RSC advances 2019 v.9 no.16 pp. 9049-9052
ISSN:
2046-2069
Subject:
copper,   etc   ; ligands; thiols; zinc;     Show all 4 Subjects
Abstract:
... Solvent-, acidity-, and redox-responsive thione(thiol)–disulfide interconversion were achieved by a dinuclear copper(ii) complex bearing a bis(thiosemicarbazone) (bTSC) ligand. The role of copper(ii) ion coordination was rationalized by parallel comparison with a bare bTSC ligand and zinc(ii) bTSC complexes under identical reaction conditions. ...
DOI:
10.1039/c9ra01115c

2. Copper-catalyzed cross-dehydrogenative coupling between quinazoline-3-oxides and indoles

Author:
Yang, Qin; Yin, Zhijian; Zheng, Lifang; Yuan, Jianjun; Wei, Song; Ding, Qiuping; Peng, Yiyuan
Source:
RSC advances 2019 v.9 no.11 pp. 5870-5877
ISSN:
2046-2069
Subject:
copper,   etc   ; air; catalysts; indoles;     Show all 4 Subjects
Abstract:
... A novel and simple protocol for the synthesis of 4-(indole-3-yl)quinazolines via cross-dehydrogenative coupling of quinazoline-3-oxides and indoles under an air atmosphere has been developed. A series of biheteroaryl products were obtained in moderate to good yields. ...
DOI:
10.1039/c8ra09864f

3. A platform direct compression formulation for low dose sustained-release tablets enabled by a dual particle engineering approach

Author:
Sun, Wei-Jhe; Chen, Hongbo; Aburub, Aktham; Sun, Changquan Calvin
Source:
Powder technology 2019 v.342 pp. 856-863
ISSN:
0032-5910
Subject:
copper nanoparticles,   etc   ; drugs; powders;     Show all 3 Subjects
Abstract:
... Content uniformity (CU) is a well-recognized challenge for low-dose direct compression (DC) tablet formulations. Using a dual particle engineering approach that involves a) forming a segregation-resistant drug-carrier composite to improve CU and b) nanocoating HPMC to enhance flowability, we have developed a platform DC formulation for preparing low-dose drug sustained-release (SR) tablets with ex ...
DOI:
10.1016/j.powtec.2018.10.054

4. Carbon fibers having a nano-arched structure on Co-supersaturated Cu foils

Author:
Odaira, Takumi; Kameoka, Satoshi; Aono, Masami; Terauchi, Masami; Tsai, An-Pang
Source:
Carbon 2019 v.147 pp. 154-156
ISSN:
0008-6223
Subject:
copper; copper nanoparticles,   etc   ; carbon fibers; cobalt; ethylene; foil; graphene; hydrogen;     Show all 8 Subjects
Abstract:
... A unique nano-arched carbon fiber (NACF) structure was formed on Cu-1at.%Co foil prepared by melt-spinning. NACFs were generated in a flow of a C2H4 + H2 (1:1) mixture at both 823 and 873 K on the surfaces of Co particles embedded in the Cu foil. Each NACF was a bundle of a large number of small rods that gradually changed their longitudinal orientations along the [001] graphite growth direction. ...
DOI:
10.1016/j.carbon.2019.02.021

5. Layer-by-layer synthesis of bilayer and multilayer graphene on Cu foil utilizing the catalytic activity of cobalt nano-powders

Author:
Ying, Hao; Wang, Weiwei; Liu, Wenyu; Wang, Le; Chen, Shanshan
Source:
Carbon 2019 v.146 pp. 549-556
ISSN:
0008-6223
Subject:
copper; copper nanoparticles,   etc   ; catalysts; catalytic activity; cobalt; engineering; foil; graphene;     Show all 8 Subjects
Abstract:
... Layer-by-layer synthesis of graphene films has been of considerable interest for the precise layer engineering. However, the additional graphene layer typically forms on the Cu surface but underneath the existing graphene layer, limited by the catalytic substrate mediated growth mechanism. This work introduces a reliable cobalt (Co) nano-powders (NP) assisted technique to synthesis the bilayer gra ...
DOI:
10.1016/j.carbon.2019.02.024

6. Tailoring Co-assembly of Nanodiscs and Block Copolymer-Based Supramolecules by Manipulating Interparticle Interactions

Author:
Hsu, Su-Wen; Xu, Ting
Source:
Macromolecules 2019 v.52 no.7 pp. 2833-2842
ISSN:
1520-5835
Subject:
copper; copper nanoparticles,   etc   ; anisotropy; composite polymers; ligands; nanocomposites;     Show all 6 Subjects
Abstract:
... Anisotropic nanoparticles exhibit interesting properties and their controlled assemblies are highly desirable to generate functional materials. Different from their spherical counterparts, the incorporation of anisotropic nanoparticles in nanostructured polymeric matrices such as block copolymer or supramolecules depends not only on the particle/polymer interactions and relative size ratio between ...
DOI:
10.1021/acs.macromol.9b00069

7. Improved Stability of Metal Nanowires via Electron Beam Irradiation Induced Surface Passivation

Author:
Luo, Beibei; Fang, Yunsheng; Li, Jia; Huang, Zhen; Hu, Bin; Zhou, Jun
Source:
ACS applied materials & interfaces 2019 v.11 no.13 pp. 12195-12201
ISSN:
1944-8252
Subject:
copper; copper nanoparticles,   etc   ; corrosion; irradiation; nanosilver; nanowires; silver;     Show all 7 Subjects
Abstract:
... Suppressing the corrosion of nanoscaled metal materials is a critical issue for various devices. Herein, we demonstrate the electron beam irradiation can be a simple and efficient method to realize silver/copper nanowires protection by transforming the original organic capping agents into dense carbonaceous shells. Single nanowire tests prove the significant stability improvement from 4 days to 20 ...
DOI:
10.1021/acsami.9b00875

8. Organic Molecular Tuning of Many-Body Interaction Energies in Air-Suspended Carbon Nanotubes

Author:
Tanaka, Shunsuke; Otsuka, Keigo; Kimura, Kensuke; Ishii, Akihiro; Imada, Hiroshi; Kim, Yousoo; Kato, Yuichiro K.
Source:
Journal of physical chemistry 2019 v.123 no.9 pp. 5776-5781
ISSN:
1932-7455
Subject:
copper; copper nanoparticles,   etc   ; adsorption; carbon nanotubes; energy; photoluminescence; screening; spectroscopy;     Show all 8 Subjects
Abstract:
... We investigate adsorption effects of copper phthalocyanine molecules on excitons and trions in air-suspended carbon nanotubes. Using photoluminescence excitation spectroscopy, we observe that exciton energy red-shifts gradually with the molecular deposition thickness. The trion emission is also observed at large deposition amounts, which indicates charge transfer between the phthalocyanine molecul ...
DOI:
10.1021/acs.jpcc.8b12496

9. Rapid Programmable Nanodroplet Motion on a Strain-Gradient Surface

Author:
Zhang, Baidu; Liao, Xiangbiao; Chen, Youlong; Xiao, Hang; Ni, Yong; Chen, Xi
Source:
Langmuir 2019 v.35 no.7 pp. 2865-2870
ISSN:
1520-5827
Subject:
copper; copper nanoparticles,   etc   ; deformation; graphene; models; molecular dynamics;     Show all 6 Subjects
Abstract:
... When a nanodroplet is placed on a lattice surface, an inhomogeneous surface strain field perturbs the balance of van der Waals force between the nanodroplet and surface, thus providing a net driving force for nanodroplet motion. Using molecular dynamics and theoretical analysis, we study the effect of strain gradient on modulating the movement of a nanodroplet. Both modeling and simulation show th ...
DOI:
10.1021/acs.langmuir.8b03774

10. Radial micro-cracks in pile-up region of single-crystal Cu in spherical indentation: experimental observation and crystal plastic simulation

Author:
Sun, Zhankun; Li, Fuguo; Zhu, Jinmeng
Source:
Journal of materials science 2019 v.54 no.13 pp. 9875-9886
ISSN:
0022-2461
Subject:
copper,   etc   ; finite element analysis; plasticity;     Show all 3 Subjects
Abstract:
... Spherical indentations with deep penetration were conducted to single-crystal Cu along [001] direction. Zigzag slip bands induced by intersection of two groups of slip bands were found in the indentation pile-up region. On the material surface in the indentation pile-up region, micro-cracks were initiated along the slip bands radial to the indentation impression. The initiation of the micro-crack ...
DOI:
10.1007/s10853-019-03590-w

11. Copper (II) catalyzed homocoupling and heterocoupling of terminal alkynes

Author:
Holganza, Maria Katrina; Trigoura, Leslie; Elfarra, Suzanne; Seo, Yoona; Oiler, Jeremy; Xing, Yalan
Source:
Tetrahedron letters 2019 v.60 no.17 pp. 1179-1181
ISSN:
0040-4039
Subject:
copper,   etc   ; alkynes; chemical reactions; moieties;     Show all 4 Subjects
Abstract:
... Cu(OTf)2 catalyzed homo– and heterocoupling of aromatic and aliphatic terminal alkynes has been developed. Symmetric and unsymmetric 1,3-diynes have been synthesized in good yields under an aerobic condition in the presence of an organic base DBU. This reaction features mild conditions, a wide substrate scope, and excellent functional group compatibility. ...
DOI:
10.1016/j.tetlet.2019.03.057

12. Defects guided wrinkling in graphene on copper substrate

Author:
Pang, Zhenqian; Deng, Bing; Liu, Zhongfan; Peng, Hailin; Wei, Yujie
Source:
Carbon 2019 v.143 pp. 736-742
ISSN:
0008-6223
Subject:
copper,   etc   ; engineering; graphene; temperature; vapors;     Show all 5 Subjects
Abstract:
... Pristine graphene depositing on metallic substrates often wrinkles when the film-substrate system undergoes a temperature drop from the chemical vapor deposition (CVD) chamber to ambient environment. The pattern of wrinkles is governed by the crystallographic planes of the substrates and the defects in the film. In this paper, we report how commonly seen Stone-Wales defects and grain boundaries (G ...
DOI:
10.1016/j.carbon.2018.11.059

13. Development of supramolecular shape-memory polyurethanes based on Cu(II)–pyridine coordination interactions

Author:
Zou, Faxing; Chen, Heng; Chen, Shaojun; Zhuo, Haitao
Source:
Journal of materials science 2019 v.54 no.6 pp. 5136-5148
ISSN:
0022-2461
Subject:
copper,   etc   ; engineering; mixing; polyurethanes; pyridines;     Show all 5 Subjects
Abstract:
... Shape-memory polymers with supramolecular switch have received increasing attention. This study reports the synthesis and characterization of supramolecular shape-memory polyurethane based on Cu(II)–pyridine coordination, obtained by mixing pyridine containing polyurethane with CuCl₂. The results show that there are strong metal–ligand coordination interactions formed between Cu(II) and the pyridi ...
DOI:
10.1007/s10853-018-3179-2

14. Modulation of catalyst enantioselectivity through reversible assembly of supramolecular helices

Author:
Li, Yan; Caumes, Xavier; Raynal, Matthieu; Bouteiller, Laurent
Source:
Chemical communications 2019 v.55 no.15 pp. 2162-2165
ISSN:
1364-548X
Subject:
copper,   etc   ; catalysts; chemical reactions; enantioselectivity;     Show all 4 Subjects
Abstract:
... A multi-configurable catalyst, for which the degree of enantioinduction in successive reactions is varied between 6% ee and 52% ee, is achieved by supporting copper centres at the periphery of supramolecular helices. Precise characterization of the co-assemblies corroborates the relation between helix length and catalyst selectivity. ...
DOI:
10.1039/c8cc09819k

15. Heterogeneous copper-catalyzed direct reduction of C-glycosidic enones to saturated alcohols in water

Author:
Petitjean, L.; de Winter, T. M.; Petrovic, P. V.; Coish, P.; Hitce, J.; Moreau, M.; Bordier, T.; Erythropel, H. C.; Anastas, P. T.
Source:
Green chemistry 2019 v.21 no.2 pp. 238-244
ISSN:
1463-9270
Subject:
copper,   etc   ; catalysts; green chemistry; sugars;     Show all 4 Subjects
Abstract:
... We report a novel method for the reduction of α,β-unsaturated enones to the corresponding fully saturated alcohols in a single procedure. Remarkably, the method employs a heterogeneous copper catalyst in water and only requires resin-treatment for isolation of C-glycosidic alcohols as pure, diastereomeric mixtures. Our methodology was applied to the reduction of aromatic and aliphatic enones which ...
DOI:
10.1039/c8gc02815j

16. MoSe₂–Cu₂S Vertical p–n Nanoheterostructures for High-Performance Photodetectors

Author:
Hassan, Md. Samim; Bera, Susnata; Gupta, Divya; Ray, Samit K.; Sapra, Sameer
Source:
ACS applied materials & interfaces 2019 v.11 no.4 pp. 4074-4083
ISSN:
1944-8252
Subject:
copper,   etc   ; molybdenum; photons; selenium; sulfides;     Show all 5 Subjects
Abstract:
... Heterostructures based on atomically thin two-dimensional layered transition metal dichalcogenides are highly promising for optoelectronic device applications owing to their tunable optical and electronic properties. However, the synthesis of heterostructures with desired materials having proper interfacial contacts has been a challenging task. Here, we develop a colloidal synthetic route for the ...
DOI:
10.1021/acsami.8b16205

17. Comparative tissue distribution and depuration characteristics of copper nanoparticles and soluble copper in rainbow trout (Oncorhynchus mykiss)

Author:
Lindh, Stina; Razmara, Parastoo; Bogart, Sarah; Pyle, Gregory
Source:
Environmental toxicology and chemistry 2019 v.38 no.1 pp. 80-89
ISSN:
0730-7268
Subject:
copper; copper nanoparticles; copper sulfate,   etc   ; Oncorhynchus mykiss; fish; gills; intestines; kidneys; liver; tissue distribution; toxicity;     Show all 11 Subjects
Abstract:
... The continuously growing number of products containing nanoparticles (NPs) makes their presence in the environment inevitable, and given the well‐known toxicity of dissolved metals, concerns regarding the toxicity of metal‐based NPs have been raised. Whether metal‐based NPs present similar or different toxicological effects compared with metal salts is an emerging field. In the present study, rain ...
DOI:
10.1002/etc.4282

18. A novel coumarin-based fluorescent probe for sensitive detection of copper(II) in wine

Author:
Wu, Xiaoming; Wang, Hao; Yang, Shaoxiang; Tian, Hongyu; Liu, Yongguo; Sun, Baoguo
Source:
Food chemistry 2019 v.284 pp. 23-27
ISSN:
0308-8146
Subject:
copper,   etc   ; detection limit; fluorescence; fluorescent dyes; wines;     Show all 5 Subjects
Abstract:
... A novel coumarin-based fluorescent probe (probe 1) for the detection of copper(II) was developed. The fluorescence intensity of probe 1 showed a linear relationship with the concentration of copper(II) in the range 0–16 μM (0–1.02 mg/L) and the limit of detection was 62 nM (3.94 µg/L). The luminescence of probe 1 at the maximum allowable amounts of copper(II) in wine and water could be observed wi ...
DOI:
10.1016/j.foodchem.2019.01.090

19. Iodo-trihalomethanes formation during chlorination and chloramination of iodide-containing waters in the presence of Cu2+

Author:
Liu, Jing; Wang, Jing; Zhang, Jie; Mu, Yang
Source:
The Science of the total environment 2019 v.671 pp. 101-107
ISSN:
0048-9697
Subject:
copper,   etc   ; chlorination; disinfection; humic acids; models; oxidants;     Show all 6 Subjects
Abstract:
... In this study, the impact of Cu2+ on the formation of iodo-trihalomethanes (I-THMs) during chlorination and chloramination of iodide-containing waters was investigated. Initially, the oxidant consumption and evolution of hypoiodous acid (HOI) were determined during disinfection in the presence of Cu2+ and the interaction between natural organic matter humic acid (HA) and Cu2+ was also analyzed. Su ...
DOI:
10.1016/j.scitotenv.2019.03.356

20. Copper-catalyzed enantioselective addition of alcohols to isatin-derived ketimines

Author:
Lu, Jian; Sha, Feng; Wu, Xin-Yan
Source:
Tetrahedron letters 2019 v.60 no.17 pp. 1161-1165
ISSN:
0040-4039
Subject:
copper,   etc   ; chemical reactions; chemical structure; enantioselectivity; ketimines;     Show all 5 Subjects
Abstract:
... The first copper-catalyzed enantioselective addition of alcohols to imines was described. In the presence of 1 mol% Cu(OAc)2 complexed with chiral cyclohexane-based N,P-ligand L4, chiral isatin-derived N,O-aminals were obtained in excellent yields (93–99%) and good-to-excellent enantioselectivities (up to 93% ee) under mild conditions. ...
DOI:
10.1016/j.tetlet.2019.03.049