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31.
Dr. Shu Min Tan Dr. Carmen C. Mayorga-Martinez Prof. Zdeněk Sofer Prof. Martin Pumera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6479-6483
Efficient exfoliation and downsizing of Sb2S3 and Bi2S3 layered compounds by using scalable bipolar electrochemistry on their suspensions in aqueous media are here demonstrated. The resulting samples were characterized in detail by transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy; their electrochemistry toward hydrogen evolution was also investigated. Hydrogen evolution ability of exfoliated Sb2S3 and Bi2S3 was investigated and compared to the bulk counterparts. 相似文献
32.
Kang Yang Chang-Shan Yang Xing-Xian Dong Dr. Yu-Hui Tan Prof. Yun-Zhi Tang Dr. Wen-Juan Wei 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(26):5887-5892
Smart multifunctional molecular ferroelectrics bearing high Curie temperatures and diverse excellent physical properties, such as second harmonic generation (SHG) responses, luminescence, and semiconductivity, among others, have significant applications but have seldom been documented. Herein, the rare-earth metals Nd and Pr are introduced into a simple molecular system (nBu4N )3[M(NO3)x(SCN)y] (nBu4N=tetrabutyl ammonium, M=rare-earth metal, nBu=CH3CH2CH2CH2), and two new multifunctional molecular ferroelectrics are obtained: (nBu4N )3[Nd(NO3)4(SCN)2] ( 1 ) and (nBu4N )3[Pr(NO3)4(SCN)2] ( 2 ). Their distinct heat and dielectric anomaly dependence on temperature verifies that compounds 1 and 2 experience high-temperature para-ferroelectric phase transitions at 408 and 413 K, respectively. Strikingly, both molecular ferroelectrics possess large spontaneous polarization with Ps values of 9.05 and 8.50 μC cm−2, respectively, and are further characterized by the appearance of multiple intersecting non-180° domains and polarization switching behavior. In particular, compounds 1 and 2 show good stability with only a small decrease in SHG intensity after switching cycles, suggesting that they have great potential for application in nonlinear optical (NLO) switches. Simultaneously, the rare-earth compounds 1 and 2 present bright yellow–red and bright green fluorescence, respectively, at room temperature. 相似文献
33.
Dr. Jiaqing Wang Weiyi Tan Dr. Guanying Li Difei Wu Hongjian He Jiashu Xu Meihui Yi Prof. Dr. Ye Zhang S. Ali Aghvami Prof. Dr. Seth Fraden Prof. Dr. Bing Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(66):15116-15120
Although lipids contribute to cancer drug resistance, it is challenging to target diverse range of lipids. Here, we show enzymatically inserting exceedingly simple synthetic lipids into membranes for increasing membrane tension and selectively inhibiting drug resistant cancer cells. The lipid, formed by conjugating dodecylamine to d -phosphotyrosine, self-assembles to form micelles. Enzymatic dephosphorylation of the micelles inserts the lipids into membranes and increases membrane tension. The micelles effectively inhibit a drug resistant glioblastoma cell (T98G) or a triple-negative breast cancer cell (HCC1937), without inducing acquired drug resistance. Moreover, the enzymatic reaction of the micelles promotes the accumulation of the lipids in the membranes of subcellular organelles (e.g., endoplasmic reticulum (ER), Golgi, and mitochondria), thus activating multiple regulated cell death pathways. This work, in which for the first time membrane tension is increased to inhibit cancer cells, illustrates a new and powerful supramolecular approach for antagonizing difficult drug targets. 相似文献
34.
35.
Wang Xinglei Guo Hangxu Wang Fan Tan Tianshe Wu Hang Zhang Hongxia 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(3):1151-1165
Journal of Radioanalytical and Nuclear Chemistry - In this study, the halloysite nanotubes was characterized and the adsorption of Th(IV) and U(VI) on halloysite nanotubes was investigated as a... 相似文献
36.
Sustainable synthesis of quinolines (pyridines) catalyzed by a cheap metal Mn(I)-NN complex catalyst
This study represents the first example of a bidentate phosphine-free manganese(I)-NN complex catalyst for the synthesis of quinolines (pyridines) through acceptorless dehydrogenative condensation of various secondary alcohols with amino alcohols. The coupling reactions occurred at 3 mol% catalyst loading and 110°C, and tolerated diverse functional groups. Moderate to excellent yields ranging from 45% to 89% were achieved after 12 hr of reaction. The present protocol provides a concise and environmentally friendly method for the construction of heterocyclic compounds. 相似文献
37.
Overview of finite elements simulation of temperature profile to estimate properties of materials 3D-printed by laser powder-bed fusion 下载免费PDF全文
Habimana Jean Willy 李辛未 Yong Hao Tan 陈哲 Mehmet Cagirici Ramadan Borayek Tun Seng Herng Chun Yee Aaron Ong 李朝将 丁军 《中国物理 B》2020,(4):98-109
Laser powder bed fusion(LPBF),like many other additive manufacturing techniques,offers flexibility in design expected to become a disruption to the manufacturing industry.The current cost of LPBF process does not favor a try-anderror way of research,which makes modelling and simulation a field of superior importance in that area of engineering.In this work,various methods used to overcome challenges in modeling at different levels of approximation of LPBF process are reviewed.Recent efforts made towards a reliable and computationally effective model to simulate LPBF process using finite element(FE)codes are presented.A combination of ray-tracing technique,the solution of the radiation transfer equation and absorption measurements has been used to establish an analytical equation,which gives a more accurate approximation of laser energy deposition in powder-substrate configuration.When this new analytical energy deposition model is used in in FE simulation,with other physics carefully set,it enables us to get reliable cooling curves and melt track morphology that agree well with experimental observations.The use of more computationally effective approximation,without explicit topological changes,allows to simulate wider geometries and longer scanning time leading to many applications in real engineering world.Different applications are herein presented including:prediction of printing quality through the simulated overlapping of consecutive melt tracks,simulation of LPBF of a mixture of materials and estimation of martensite inclusion in printed steel. 相似文献
38.
To make further understanding of terahertz(THz)wave generation from liquid water,we study THz wave emission from water lines of different diameters.The water line with a smaller diameter generates a stronger THz electric field for the diameters from 0.2 mm to 0.5 mm.The THz electric field strength and polarity change with the relative position between the incident laser and water line.Moreover,the THz energy has an optimal radiation angle of about 60°.A two-dimensional dipole array model is introduced to illustrate the phenomenon.Our observations contribute to optimizing the scheme of the liquid THz source. 相似文献
39.
Tan Wei Ren Yuanlin Guo Yingbin Liu Yansong Liu Xiaohui Qu Hongqiang 《Cellulose (London, England)》2022,29(12):6941-6962
Cellulose - A novel DOPO derived multi-claw reactive flame retardant (DMCFR) was designed to improve the flame retardancy of lyocell fabric. The chemical structure of DMCFR was identified by proton... 相似文献
40.
Nonlinear Dynamics - Despite depleting the resources in their environments, some species and societies are capable of sustainable habitat expansion by alternating between a low-growth migratory... 相似文献