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91.
Mingtian Li Jun Huang Xuan Zhou Hua Fang Liyun Ding 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(7):m250-m253
The structures reported herein, viz. bis(4‐aminonaphthalene‐1‐sulfonato‐κO)bis(4,5‐diazafluoren‐9‐one‐κ2N,N′)copper(II), [Cu(C10H8NO3S)2(C11H6N2O)2], (I), and poly[[[diaquacadmium(II)]‐bis(μ‐4‐aminonaphthalene‐1‐sulfonato)‐κ2O:N;κ2N:O] dihydrate], {[Cd(C10H8NO3S)2(H2O)2]·2H2O}n, (II), are rare examples of sulfonate‐containing complexes where the anion does not fulfill a passive charge‐balancing role, but takes an active part in coordination as a monodentate and/or bridging ligand. Monomeric complex (I) possesses a crystallographic inversion center at the CuII atom, and the asymmetric unit contains one‐half of a Cu atom, one complete 4‐aminonaphthalene‐1‐sulfonate (ans) ligand and one 4,5‐diazafluoren‐9‐one (DAFO) ligand. The CuII atom has an elongated distorted octahedral coordination geometry formed by two O atoms from two monodentate ans ligands and by four N atoms from two DAFO molecules. Complex (II) is polymeric and its crystal structure is built up by one‐dimensional chains and solvent water molecules. Here also the cation (a CdII atom) lies on a crystallographic inversion center and adopts a slightly distorted octahedral geometry. Each ans anion serves as a bridging ligand linking two CdII atoms into one‐dimensional infinite chains along the [010] direction, with each CdII center coordinated by four ans ligands via O and N atoms and by two aqua ligands. In both structures, there are significant π–π stacking interactions between adjacent ligands and hydrogen bonds contribute to the formation of two‐ and three‐dimensional networks. 相似文献
92.
析氧反应(OER)被认为是电解水的关键限制步骤,已被广泛作为清洁能源方式用于解决能源和环境问题。钙钛矿氧化物(ABO3)具有可调的电子结构、高灵活性的元素组成,能在OER中表现出良好的催化活性。然而,钙钛矿氧化物的合成通常需要经历长时间的高温,极易导致金属的聚集和影响材料的本征活性。气相微波技术可以显著缩短热处理时间,从而减少相关的碳排放。这项技术不仅解决了对碳中性过程日益增长的需求,而且还增加了对合成的控制,以避免产品的不良团聚。本文采用微波热冲法快速制备了二维(2D)多孔La0.2Sr0.8CoO3钙钛矿。伴随微波过程的快速熵增可以有效地暴露La0.2Sr0.8CoO3结构中丰富的活性位点。此外,高能微波冲击过程可以精准地将Sr2+引入到LaCoO3的晶格中,通过增加Co的氧化态来增加氧空位量。这种锶元素取代镧引入的氧空位能极大提高催化剂的本征催化活性。对于碱性电解液中的OER应用,制备的La0.2Sr0.8CoO3在10 mA∙cm−2下展现出了360 mV的过电位,Tafel斜率为76.6 mV∙dec−1。且在经历30000秒的长时间循环测试后仍能维持初始电流密度的97%。这项研究为高活性二维钙钛矿的合成提供了一种简便、快速的策略。 相似文献
93.
Xiaolin Hou Lanlan Wu Ling Yuan Liyun Huang Zhanxiang Jia Yang Chen 《Journal of Radioanalytical and Nuclear Chemistry》1994,185(1):109-118
19 elements, such as Ca, Mg, Fe, Se, Cu, Zn, etc., in hair of 65 patients with chronic bronchitis, pulmonary emphysema and cor-pulmonale diseases and 65 healthy people have been investigated by instrumental neutron activation analysis. The results show that the contents of Ca and Mg are lower and Fe, As and Co are higher in the hair of patients than in healthy persons. The contents of Ca and Mg are lower and Fe is higher in the hair of patients during attack periods of chronic bronchitis than in relaxed periods. The differences are significant (P<0.05–0.01). The content of Ca is closely related to that of Mg in hair (P<0.01). The contents of inorganic elements in the Chinese medicine cough and asthma capsule used to treat chronic bronchitis have been determined. The results show that the contents of elements Ca, Mg, Sr, etc., are higher in this medicine than the average amounts of these elements in 120 other Chinese medicines. 相似文献
94.
Liyun Yu Anne Ladegaard Skov Hussein M. Etmimi Peter E. Mallon Alex Adronov Michael A. Brook 《Journal of polymer science. Part A, Polymer chemistry》2016,54(15):2379-2385
While graphene or graphene oxide can make significant improvements in the properties of a wide variety of polymeric materials, their incorporation can be challenged by incompatibility with the polymeric matrix. The modification of graphene oxide with silicones or silanes using the Piers‐Rubinsztajn reaction improves dispersibility in nonpolar materials, including organic solvents and silicone pre‐elastomers. A high loading (up to 10 wt %) of modified graphene oxide in silicone elastomers could be achieved, which resulted in enhanced mechanical performance and reduced gas permeability. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2379–2385 相似文献
95.
Study of Static Adsorption Capacity of ACF for Xenon at 201 K 总被引:2,自引:0,他引:2
WANG Ya long ** ZHANG Hai tao WANG Xu hui ZHANG Li xing CHEN Li yun XIE Jin chuan 《高等学校化学研究》2002,18(2):216-220
IntroductionTheradioxenonsarenuclearfissionproducts .AccordingtotheComprehensiveNuclear Test BanTreaty (CTBT) ,thenucleareventswhichviolatethetreatymaybefoundbymonitoringradioxenonsinglobalatmospherewithInternationalMonitoringSys tem(IMS) .However ,allxenons… 相似文献
96.
Leheng Wang Wenping Wang Hao Chi Yanjie Wu You Li Yan Fu Chen Zhou Ruixiang Sun Haipeng Wang Chao Liu Zuofei Yuan Liyun Xiu Si‐Min He 《Rapid communications in mass spectrometry : RCM》2010,24(12):1791-1798
Protein sequence database search based on tandem mass spectrometry is an essential method for protein identification. As the computational demand increases, parallel computing has become an important technique for accelerating proteomics data analysis. In this paper, we discuss several factors which could affect the runtime of the pFind search engine and build an estimation model. Based on this model, effective on‐line and off‐line scheduling methods were developed. An experiment on the public dataset from PhosphoPep consisting of 100 RAW files of phosphopeptides shows that the speedup on 100 processors is 83.7. The parallel version can complete the identification task within 9 min, while a stand‐alone process on a single PC takes more than 10 h. On another larger dataset consisting of 1 366 471 spectra, the speedup on 320 processors is 258.9 and the efficiency is 80.9%. Our approach can be applied to other similar search engines. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
97.
98.
In this article, a decoupling scheme based on two‐grid finite element for the mixed Stokes‐Darcy problem with the Beavers‐Joseph interface condition is proposed and investigated. With a restriction of a physical parameter α, we derive the numerical stability and error estimates for the scheme. Numerical experiments indicate that such two‐grid based decoupling finite element schemes are feasible and efficient. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 1066–1082, 2014 相似文献
99.
Liyun Zhang Jun Cheng Er Wang Xu Xian Qin Animesh Samanta Santanu Jana Chi-Lik Ken Lee Young-Tae Chang 《Analytica chimica acta》2014
Due to the prevalent use of polycarbonate plastics and epoxy resins in packaging materials and paints for ships, there has been a widespread global contamination of environmental water sources with bisphenol A (BPA). BPA, an endocrine disruptor, has been found to cause tremendous health problems. Therefore, there is an urgent need for detecting BPA in a convenient and sensitive manner to ensure water safety. Herein, we develop a fluorescent turn-on BPA probe, named Bisphenol Orange (BPO), which could conveniently detect BPA in a wide variety of real water samples including sea water, drain water and drinking water. BPO shows superior selectivity toward BPA and up to 70-fold increase in fluorescence emission at 580 nm when mixed with BPA in water. Mechanistic studies suggest a plausible water-dependent formation of hydrophobic BPA clusters which favorably trap and restrict the rotation of BPO and recover its inherent fluorescence. 相似文献
100.