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111.
Bin Zhou Yedi Xing Prof. Shu Miao Prof. Mingrun Li Prof. Wen‐Hua Zhang Prof. Can Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(39):12426-12431
A facile colloidal approach to synthesize Ag8(Ge1?x,Snx)(S6?y,Sey) nanocrystals (NCs) in a highly controlled way across the entire compositional ranges (0≤x≤1, 0≤y≤6) has been developed. The NCs exhibit a uniform size distribution, highly crystalline structure, over 1 g scalable synthesis, and tunable band gaps in the range of 0.88–1.45 eV by varying their chemical compositions. The Ag8GeS6 NCs with a band gap of approximately 1.45 eV were employed as a model light harvester to assess their applicability in solar cells by a full solution‐processing device, yielding an efficiency of 0.28 % under AM1.5 illumination, demonstrating their application potential in solar energy utilization. 相似文献
112.
Solvothermal Transformation of a Calcium Oleate Precursor into Large‐Sized Highly Ordered Arrays of Ultralong Hydroxyapatite Microtubes 下载免费PDF全文
Dr. Bing‐Qiang Lu Prof. Dr. Ying‐Jie Zhu Feng Chen Chao Qi Xin‐Yu Zhao Jing Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(23):7116-7121
Hydroxyapatite (HAP), a well‐known member of the calcium phosphate family, is the major inorganic component of bones and teeth in vertebrates. The highly ordered arrays of HAP structures are of great significance for hard tissue repair and for understanding the formation mechanisms of bones and teeth. However, the synthesis of highly ordered HAP structure arrays remains a great challenge. In this work, inspired by the ordered structure of tooth enamel, we have successfully synthesized three‐dimensional bulk materials with large sizes (millimeter scale) that are made of highly ordered arrays of ultralong HAP microtubes (HOAUHMs) by solvothermal transformation of calcium oleate precursor. The core–shell‐structured oblate sphere consists of a core that is composed of HAP nanorods and a shell that consists of highly ordered HAP microtube arrays. The prepared HOAUHMs are large: 6.0 mm in diameter and up to 1.4 mm in thickness. With increasing solvothermal reaction time, the HOAUHMs grow larger; the microtubes become more uniform and more ordered. This work provides a new synthetic method for synthesizing highly ordered arrays of uniform HAP ultralong microtubes that are promising for biomedical applications. 相似文献
113.
A sensitive fluorescent probe, 2,2'-bisbenzimidazole (L), for CN has been developed. This structurally simple receptor displays great selectivity for the cyanide anion over other common inorganic anions in an aqueous environment. In addition, further study demonstrates the lower detection of the fluorescence response of the sensor to CN is in 10 9 mol/L range. Thus, the present probe should be applicable as a practical system for the monitoring of cyanide concentrations in aqueous samples. 相似文献
114.
Xiaojian Shi Yelian Miao Jie Yu Chen Jun Chen Wenli Li Xun He Jining Wang 《Applied biochemistry and biotechnology》2014,172(6):3042-3053
Freeze-tolerant baker’s yeasts are required for the processing of frozen doughs. The present study was carried out to investigate the cell survival rate after frozen storage and the change of fermentability in dough due to frozen storage, and to discuss quantitatively the relationship of freeze tolerance with intracellular trehalose, amino acids, and glycerol, using six types of baker’s yeasts as the test materials. The experimental results showed that the fermentability of yeast cells in frozen dough was strongly correlated with the cell survival rate. The baker’s yeast with a higher level of cell survival rate had a larger increase in the total intracellular compound content after frozen storage, and the cell survival rate increased linearly with increasing total intracellular compound content in frozen yeast cells. Trehalose was a primary compound affecting freeze tolerance, followed by glutamic acid, arginine, proline, asparagic acid, and glycerol. The basic information provided by the present study is useful for exploring the freeze-tolerance mechanisms of baker’s yeast cells, breeding better freeze-tolerant baker’s yeast strains, and developing more effective cryoprotectants. 相似文献
115.
G-protein-coupled receptors (GPCRs) are the largest family of human membrane proteins and serve as primary targets of approximately one-third of currently marketed drugs. In particular, adenosine A1 receptor (A1AR) is an important therapeutic target for treating cardiac ischemia–reperfusion injuries, neuropathic pain, and renal diseases. As a prototypical GPCR, the A1AR is located within a phospholipid membrane bilayer and transmits cellular signals by changing between different conformational states. It is important to elucidate the lipid–protein interactions in order to understand the functional mechanism of GPCRs. Here, all-atom simulations using a robust Gaussian accelerated molecular dynamics (GaMD) method were performed on both the inactive (antagonist bound) and active (agonist and G-protein bound) A1AR, which was embedded in a 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine (POPC) lipid bilayer. In the GaMD simulations, the membrane lipids played a key role in stabilizing different conformational states of the A1AR. Our simulations further identified important regions of the receptor that interacted distinctly with the lipids in highly correlated manner. Activation of the A1AR led to differential dynamics in the upper and lower leaflets of the lipid bilayer. In summary, GaMD enhanced simulations have revealed strongly coupled dynamics of the GPCR and lipids that depend on the receptor activation state. © 2019 Wiley Periodicals, Inc. 相似文献
116.
Phosgene has attracted wide attention because of its important applications and value in modern industry, agriculture, and other fields, though it easily leaks and is difficult to detect. In this work, we designed and synthesized a naphthalimide-based fluorescent probe, which is easy to prepare, stable, and able to discriminate between phosgene, acetyl chloride, oxalyl chloride, thionyl chloride, phosphorus oxychloride, and tosyl chloride. Our results indicate that the probe can react with phosgene selectively and sensitively, showing remarkable ratiometric fluorescence changes. Furthermore, the probe can be made into test strips, which can determine phosgene in air effectively. The present work provides a novel class of naphthalimide-based derivatives with potential application in phosgene sensing in real time simply and safely with further optimization. 相似文献
117.
Mengfei Qiao Ying Wang Quan Wang Guangzhi Hu Xamxikamar Mamat Shusheng Zhang Shuangyin Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(7):2710-2716
The low catalytic activity and poor mass transport capacity of platinum group metal free (PGM-free) catalysts seriously restrict the application of proton-exchange membrane fuel cells (PEMFCs). Catalysts derived from Fe-doped ZIF-8 could in theory be as active as Pt/C thanks to the high intrinsic activity of FeN4; however, the micropores fail to meet rapid mass transfer. Herein, an ordered hierarchical porous structure is introduced into Fe-doped ZIF-8 single crystals, which were subsequently carbonized to obtain an FeN4-doped hierarchical ordered porous carbon (FeN4/HOPC) skeleton. The optimal catalyst FeN4/HOPC-c-1000 shows excellent performance with a half-wave potential of 0.80 V in 0.5 m H2SO4 solution, only 20 mV lower than that of commercial Pt/C (0.82 V). In a real PEMFC, FeN4/HOPC-c-1000 exhibits significantly enhanced current density and power density relative to FeN4/C, which does not have an optimized pore structure, implying an efficient utilization of the active sites and enhanced mass transfer to promote the oxygen reduction reaction (ORR). 相似文献
118.
Anthony Jolly Dandan Miao Maxime Daigle Jean‐Franois Morin 《Angewandte Chemie (International ed. in English)》2020,59(12):4624-4633
The solution‐phase synthesis is one of the most promising strategies for the preparation of well‐defined graphene nanoribbons (GNRs) in large scale. To prepare high quality, defect‐free GNRs, cycloaromatization reactions need to be very efficient, proceed without side reaction and mild enough to accommodate the presence of various functional groups. In this Minireview, we present the latest synthetic approaches for the synthesis of GNRs and related structures, including alkyne benzannulation, photochemical cyclodehydrohalogenation, Mallory and Pd‐ and Ni‐catalyzed reactions. 相似文献
119.
120.
在异质性生境中,种内功能性状变异有助于植物对环境的适应,进而影响种群更新、群落构建和生态系统过程。探讨了种内叶经济性状的变异及受生境异质性的塑造情况。以千岛湖片段化生境中的常见种檵木(Loropetalum chinense )的幼苗为研究对象,测定了200株檵木幼苗个体水平的7个叶经济性状(比叶面积SLA、叶全碳量C、叶全氮量N等)及其对应的生境因子(郁闭度、土壤全碳量、土壤全氮量等),采用相关性检验、主成分分析和线性混合效应模型等方法探讨片段化森林中檵木幼苗的种内叶经济性状变异及生境异质性对该变异的驱动作用。结果显示:(1) 在7个叶经济性状所构成的21对相关性分析中,有12对显著相关。经主成分分析降维后,主成分1(PC1)占性状总变异的43.02%,主要与比叶面积、叶绿素浓度、叶全氮量呈正相关,与叶干物质质量分数和叶碳氮比呈负相关,体现了檵木的种内叶经济谱,可反映叶片的最大光合效率。(2)片段化对生境条件和叶经济性状均有影响。岛屿森林群落的郁闭度显著低于大陆。相对于大陆,岛屿中的檵木幼苗趋向于更小的PC1值(缓慢投资-收益策略);大岛边缘较大岛内部偏向于更小的PC1值。(3)生境因子中,郁闭度对PC1具有显著正效应。研究表明,片段化生境中的檵木在幼苗阶段存在叶经济谱,生境片段化可通过影响生境条件进而改变檵木幼苗的叶经济性状。随着生境片段化程度的加剧,檵木幼苗的叶经济性状逐渐向缓慢投资-收益策略靠拢。 相似文献