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991.
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Nitroarenes can be reduced to the corresponding primary amines in good yields with Cp2TiCl2/Sm system under mild and neutral conditions.  相似文献   
994.
995.
Pua  Aileen  Goh  Rui Min Vivian  Ee  Kim-Huey  Huang  Yunle  Liu  Shao Quan  Lassabliere  Benjamin  Yu  Bin 《Chromatographia》2021,84(5):507-515
Chromatographia - The separation of isomers is one of the key issues in analysing complex natural matrices, thus commanding a higher separating power from the applied analytical system. In this...  相似文献   
996.
Li  Wei  Peng  Min  Pan  Yong  Wu  Yi  Long  Minghui  Lei  Longlong 《Chromatographia》2021,84(11):1049-1056
Chromatographia - An automated online column extraction coupled with high-performance liquid chromatography (HPLC) and equipped with a double-trap column system was developed to determine valproic...  相似文献   
997.
Chiral compounds are known to be important not only because they are the fundamental components of living organisms, but also for their unique chiroptical properties. In recent years, scientists have fabricated several chiral organic supramolecular aggregates by using chiral physical fields, such as vortex flow. Herein, the relationship between dynamic chiroptical properties and rheological nature is discussed, suggesting the shear thinning properties of non-Newtonian fluids might help colloidal particles adopt a chiral arrangement in vortices. Furthermore, the storage modulus of colloids could be increased by adding a linking agent, which successfully kept the dynamic chiroptical properties in the static state. Moreover, the salt effect on the host–guest interaction involved in the colloids was studied, the results suggested a significant enhancement of the transferred dynamic circular dichroism for the achiral guest molecule.  相似文献   
998.
Retaining nitrogen for polyacrylonitrile (PAN) based carbon anode is a cost-effective way to make full use of the advantages of PAN for sodium-ion batteries (SIBs). Here, a simple strategy has been successfully adopted to retain N atoms in situ and increase production yield of a novel composite PAZ by mixing 3 wt % of zinc borate (ZB) with poly (acrylonitrile-co-itaconic acid) (PANIA). Among the prepared carbonised fibre (CF) samples, PAZ-CF-700 maintains the highest N content, retaining 90 % of the original N from PANIA. It represents the highest capacity storage contribution (80.55 %) and the lowest impedance Rct (117 Ω). Consequently, the specific capacity increases from 60 mAh g−1 of PANIA-CF-700 to 190 mAh g−1 of PAZ-CF-700 at a current density of 100 mA g−1. At the same time, PAZ-CF-700 exhibits a good rate performance and excellent long-term cycling stability with a specific capacity of 94 mAh g−1 after 4000 cycles at 1.6 A g−1.  相似文献   
999.
The tribological properties of polyoxymethylene (POM) modified by nano-polytetrafluorethylene (nano-PTFE) were investigated by a block-on-ring wear tester. For comparison, modified POM with micro-polytetrafluoroethylene (micro-PTFE) was also studied. The modified POM with a much lower concentration of nano-PTFE showed the similar tribological properties compared with POM modified by micro-PTFE. The friction coefficient decreased with the increase of nano-PTFE, while the wear rate showed the lowest value when the concentration of nano-PTFE was 2%. Scanning electron microscope (SEM) micrographs revealed that transfer films played an important role in the friction process. The transfer films decreased and stabilized the friction coefficient. Comparing to POM/2%nano-PTFE, when the concentration of nano-PTFE reached 4%, the mechanical properties decreased significantly, possibly due to poor dispersion of nano-PTFE.  相似文献   
1000.
Yuqing Ho  Zhizhen Huang  Xian Huang 《合成通讯》2013,43(9-10):1625-1629
Aryltellurenyl iodides react with Reformatsky reagents in dry THF at room temperature rapidly to produce α-aryltelluro esters in good yields.  相似文献   
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