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81.
α-n-amylcinnamaldehyde (jasminaldehyde) was obtained with 82 % yield by solid-liquid phase transfer catalysis without solvent within 3 days at room temperature. By use of domestic microwave irradiation, the same yield was obtained within 1 minute at a power of 600 W. 相似文献
82.
Liu Han Yu Aili Liu Huiqiang Chu Sheng Tan Shaozao 《Russian Journal of Applied Chemistry》2017,90(7):1171-1180
Russian Journal of Applied Chemistry - Based on the advantages of graphene and zeolite, respectively, the graphene/zeolite composites with core-shell structure were synthesized. The features of the... 相似文献
83.
Transition-metal oxides are considered to be a promising anode material for lithium-ion batteries(LIBs)due to their high capacities,low cost,and ease of synthesis.Herein,a hybrid nanosheet composed of uniform MoO_2 nanoparticles(NPs) homogeneously immobilized on the reduced graphene oxide nanosheets(MoO_2 NP@rGO) is first synthesized by a self-templating and subsequent calcination treatment.The unique two-dimensional hybridnanosheets provides several merits.rGO can be used as a favorable support for the loading of electrochemically active MoO_2 NPs.Meanwhile,MoO_2 NPs can effectively prevent the stacking of the rGO.The effective combination of MoO_2 NPs and rGO nanosheets furnish additional electrochemically interfacial active sites for extra lithium ion sto rage.Noticeably,the as-fabricated hybrid nanosheets deliver a reversible capacity of 641 mAh/g after 350 cycles at a current density of 1000 mA/g with a good rate capability.The greatly enhanced lithium storage properties of MoO_2 NP@rGO indicate the importance of elaborate construction of novel hybrid hierarchical structures. 相似文献
84.
Mary Marshall Zhaoguo Zhu Rachel Harris Prof. Dr. Kit H. Bowen Wei Wang Jie Wang Chu Gong Prof. Dr. Xinxing Zhang 《Chemphyschem》2021,22(1):5-8
Thorium and its compounds have been widely investigated as important nuclear materials. Previous research focused on the potential use of thorium hydrides, such as ThH2, ThH4, and Th4H15, as nuclear fuels. Here, we report studies of the anion, ThH5−, by anion photoelectron spectroscopy and computations. The resulting experimental and theoretical vertical detachment energies (VDE) for ThH5− are 4.09 eV and 4.11 eV, respectively. These values and the agreement between theory and experiment facilitated the characterization of the structure of the ThH5− anion and showed its neutral counterpart, ThH5 to be a superhalogen. ThH5−, which exhibits a C4v structure with five Th−H single bonds, possesses the largest known H/M ratio among the actinide elements, M. The adaptive natural density partitioning (AdNDP) method was used to further analyze the chemical bonding of ThH5− and to confirm the existence of five Th−H single bonds in the ThH5− molecular anion. 相似文献
85.
Chu Rainer Kwang-Hua 《Journal of Experimental and Theoretical Physics》2016,123(5):822-826
We illustrate the possible acceleration of cosmic rays passing through a kind of amplification channel (via diffusion modes of propagating plane-wave fronts) induced by a rotating system. Our analysis is mainly based on the quantum discrete kinetic model (considering a discrete Uehling-Uhlenbeck collision term), which has been used to study the propagation of plane (e.g., acoustic) waves in a system of rotating gases. 相似文献
86.
87.
Progress in surface modification of magnetic nanoparticles(MNPs)is summarized with regard to organic molecules,macromolecules and inorganic materials.Many researchers are now devoted to synthesizing new types of multi-functional MNPs,which show great application potential in both diagnosis and treatment of disease.By employing an ever-greater variety of surface modification techniques,MNPs can satisfy more and more of the demands of medical practice in areas like magnetic resonance imaging(MRI),fluorescent marking,cell targeting,and drug delivery. 相似文献
88.
Kinetics and Mechanism of the Reaction of a Ruthenium(VI) Nitrido Complex with HSO3− and SO32− in Aqueous Solution 下载免费PDF全文
Dr. Qian Wang Hong Yan Zhao Dr. Wai‐Lun Man Dr. William W. Y. Lam Dr. Kai‐Chung Lau Prof. Tai‐Chu Lau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):10754-10758
The kinetics and mechanism of the reaction of SIV (SO32?+HSO3?) with a ruthenium(VI) nitrido complex, [(L)RuVI(N)(OH2)]+ (RuVIN, L=N,N′‐bis(salicylidene)‐o‐cyclohexyldiamine dianion), in aqueous acidic solutions are reported. The kinetic results are consistent with parallel pathways involving oxidation of HSO3? and SO32? by RuVIN. A deuterium isotope effect of 4.7 is observed in the HSO3? pathway. Based on experimental results and DFT calculations the proposed mechanism involves concerted N?S bond formation (partial N‐atom transfer) between RuVIN and HSO3? and H+ transfer from HSO3? to a H2O molecule. 相似文献
89.
Weihe Xu Kenneth Lauer Yong Chu Evgeny Nazaretski 《Journal of synchrotron radiation》2014,21(6):1367-1369
A rotational stage is a key component of every X‐ray instrument capable of providing tomographic or diffraction measurements. To perform accurate three‐dimensional reconstructions, runout errors due to imperfect rotation (e.g. circle of confusion) must be quantified and corrected. A dedicated instrument capable of full characterization and circle of confusion mapping in rotary stages down to the sub‐10 nm level has been developed. A high‐stability design, with an array of five capacitive sensors, allows simultaneous measurements of wobble, radial and axial displacements. The developed instrument has been used for characterization of two mechanical stages which are part of an X‐ray microscope. 相似文献
90.
Yanfeng Chu Huan Yu Yunti Zhang Guangyan Zhang Yingying Ma Renxi Zhuo Xulin Jiang 《Journal of polymer science. Part A, Polymer chemistry》2014,52(23):3346-3355
Biodegradable amphiphilic ABC Y‐shaped triblock copolymer (MPBC) containing PEG, PBLA, and PCL segments was synthesized via the combination of enzymatic ring‐opening polymerization (ROP) of epsilon‐caprolactone, ROP of BLA‐N‐carboxyanhydride and click chemistry, where PEG, PBLA, and PCL are poly(ethylene glycol), poly(benzyl‐l ‐aspartate), and polycaprolactone, respectively. Propynylamine was employed as ROP initiator for the preparation of alkynyl‐terminated PBLA and methyloxy‐PEG with hydroxyl and azide groups at the chain‐end was used as enzymatic ROP initiator for synthesis of monoazido‐midfunctionalized block copolymer mPEG‐b‐PCL. The subsequent click reaction led to the formation of Y‐shaped asymmetric heteroarm terpolymer MPBC. The polymer structures were characterized by different analyses. The MPBC terpolymer self‐assembled into micelles and physically encapsulated drug doxorubicin (DOX) to form DOX‐loaded micelles, which showed good stability and slow drug release. In vitro cytotoxicity study indicated that the MPBC micelles were nontoxic and the DOX‐loaded micelles displayed obvious anticancer activity similar to free DOX against HeLa cells. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3346–3355 相似文献