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排序方式: 共有660条查询结果,搜索用时 15 毫秒
561.
Su Qin HAN Er Bao LIU Hua LI* Institute of Analytical Science Northwest University Xi’an School of Chemistry Material Science Shanxi Normal University Linfen College of Chemistry Life Science Tianjin Normal University Tianjin 《中国化学快报》2005,(8)
Tetracycline antibiotics (TCs) are active against a wide range of gram-positive and gram-negative bacteria, being extensively used in human and veterinary medicine to treat and prevent bacterial infections1. Among the TCs, TC, OTC and CTC are commercially available and permitted for human administration. However, the degradation products occurring in storage conditions might induce potential adverse effects. Thus, many studies have focused on the development of a rapid, sensitive and reli… 相似文献
562.
Hui Pan~* Mei Qi Zhi Jun Zhang Laboratory of Special Functional Material Henan University Kaifeng PR China 《中国化学快报》2008,19(4):435-437
The radical polymerization of maleic anhydride(MA),styrene(ST)with the vinyl groups introduced onto the surface of the nano-sized silica via solution polymerization method was developed.The methacryloxypropyl nano-sized silica(MPNS)was used as macromonomer and polymerized with maleic anhydride and styrene by initiating with BPO in toluene.The structure and properties of MPNS/SMA nano-composite were characterized by FT-IR spectra and TEM.Meanwhile,it was applied as tanning agent compared with the traditional styrene-maleic anhydride copolymer in leather.It was found that the applied leather had better quality characteristics with the addition of the nano-sized silica. 相似文献
563.
Jian She Zhang Jiu Gao Yu~* Ying Wu Xiao Fei Ma School of Science Tianjin University Tianjin PR China 《中国化学快报》2008,19(4):395-398
In this paper,aliphatic amidediol was synthesized and mixed with glycerol used as a plasticizer for preparing thermoplastic starch(AGPTPS).The yield of aliphatic amidediol was 91%.FF-IR expressed that the mixture of aliphatic amidediol and glycerol formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch.By scanning electron microscope(SEM)native cornstarch granules were proved to transfer to a homogeneous continuous system.After being stored for a period time at room temperature,the mechanical properties of AGPTPS were also studied.As a mixed plasticizer,aliphatic amidediol and glycerol would be practical to extend TPS application scopes. 相似文献
564.
Hui Tang You Jun Zhou~* Yao Wu Li Jia Guo Lv Can Hui Zheng Jun Chen Ju Zhu~* Department of Medicinal Chemistry School of Pharmacy Second Military Medical University Shanghai China 《中国化学快报》2008,19(3):264-268
Novel chiral tetralin compounds were designed and synthesized, and their antifungal activities in vitro were tested. The results showed that all of target compounds had potent antifungal activities, and were stronger than that of control compounds tetrahydroisoquinolines. The binding model of lead molecules in the active site of CYP51 of Candida albicans showed that lead compound specifically interacted with the amino acids residues in the active site, without binding with the heme of CYP51, which was different from azole antifungal drugs. The present study might afford a novel lead molecule to develop non-azole CYP51 inhihitars of fungi. 相似文献
565.
Jin Cui Ming Jie Zhang~* Xiang Qian Wang Nai Jing Cui School of Science Tianjin University Tianjin China 《中国化学快报》2008,(3)
By the addition of rice wine koji,enhancement of the reactivity was observed for the baker's yeast reduction ofβ-keto esters into (S)-β-hydroxy esters with high enantiomeric purity (73-98%). 相似文献
566.
Yi Luo Ping Zhong~* Xiao Hong Zhang Qiu Lian Lin Ye Na Chen College of Chemistry Materials Science Wenzhou University Wenzhou China 《中国化学快报》2008,19(4):383-386
Two species of N-arylpyrazoles containing active amino group were synthesized.And formylations of N-arylpyazoles containing amino in different position of pyrazole rings using Vilsmeier-Haack reaction gave a series of useful pyrazole intermediates.The important features of this protocol were cheap materials,easy process,mild reaction conditions and good yield of products. 相似文献
567.
Tong Wen WANG Le Rong DAI * Institute of Physical Chemistry Peking University Beijing Department of Chemistry Yunnan Normal University Kunming 《中国化学快报》2000,11(12)
In 1992, Mobil researchers introduced a novel concept in the synthesis of mesoporous silicas (M41S)1,2 by using a self-assembled molecular array of surfactant molecules as structure-directing template. Depending on the shape of their templates and the respective resulting pore structure, the M41S family was identified : MCM-41(hexagonal), MCM-48(cubic), and other species. MCM-41 with honeycomb arrays of nonintersecting channels was shown to be the easiest to synthesize1. MCM-48 containin… 相似文献
568.
Ze Lin LI* Bin REN Chun Xing SHE Xiao Ming XIAO Zhong Qun TIAN* Department of Chemistry Hunan Normal University Changsha State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry Xiamen University Xia 《中国化学快报》2001,(10)
The research of electrocatalytic oxidation of small organic molecules such as methanol, formaldehyde and formic acid has been fascinating electrochemists for more than thirty years, owing to its significance in energy conversion and reaction mechanisms. The surface adsorbed species involved in these electrocatalytic reactions, especially reactive and poisoning intermediates, have been investigated by electrochemical, spectroscopic and other physicochemical methods1. However, Raman spectrosco… 相似文献
569.
使用密度泛函理论B3LYP方法和二阶微扰理论MP2方法对由1-甲基尿嘧啶与N-甲基乙酰胺所形成的氢键复合物中的氢键强度进行了理论研究, 探讨了不同取代基取代氢键受体分子1-甲基尿嘧啶中的氢原子对氢键强度的影响和氢键的协同性. 研究表明: 供电子取代基使N-H…O=C氢键键长r(H…O)缩短, 氢键强度增强; 吸电子取代基使N-H…O=C氢键键长r(H…O)伸长, 氢键强度减弱. 自然键轨道(NBO)分析表明: 供电子基团使参与形成氢键的氢原子的正电荷增加, 使氧原子的负电荷增加, 使质子供体和受体分子间的电荷转移量增多; 吸电子基团则相反. 供电子基团使N-H…O=C氢键中氧原子的孤对电子轨道n(O)对N-H的反键轨道σ*(N-H)的二阶相互作用稳定化能增强, 吸电子基团使这种二阶相互作用稳定化能减弱. 取代基对与其相近的N-H…O=C氢键影响更大. 相似文献
570.
特殊的单原子层二维sp2碳结构给石墨烯带来众多独特的性能和潜在的应用. 然而, 单层石墨烯容易聚集并会逐渐重新石墨化, 这成为其应用的一个重要障碍. 本文报道了一种新策略来解决这个问题, 即通过在石墨烯表面引入sp2碳纳米结构作为永久的波纹来阻止石墨烯的聚集和石墨化, 并使之在溶液中易于分散和稳定. 和其他功能化方法不同, 该方法没有引入杂原子, 不破坏石墨烯的结构和功能. 制得的石墨烯具有优异的导电性能(~65000 S·m-1), 并具有较好的溶液稳定性. 相似文献