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121.
Xiao Jian Wang Mei Yang Xi Ji Hua Fu Fu Rong Zhang a Gui Fang Cheng Da Li Yin Qi Dong You b 《中国化学快报》2012,23(6):707-710
A series of benzimidazole derivatives have been designed,synthesized and evaluated for H1 antihistamine activity.Six compounds have showed potent antihistamine H1 activity.The primary SAR analysis indicated that benzyl or benzylidinyl substituted on the exo-nitrogen atom and C2 of the benzimidazole were significant.Further experiments indicated that compound 17d displayed excellent activity to reduce mast cell degranulation,moderate anti-PAF activity and decreased potency on hERG compared to astermizole.Hence compound 17d could serve as anti-allergic agent for further development. 相似文献
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强制沉积法是一种利用自组装原理快速沉积胶体晶体有序阵列的模板方法. 我们利用微机械刻划法加工金属Al薄膜, Al膜厚控制微粒粒径和聚醚砜膜厚控制层数, 成功地制备了用于强制沉积光子晶体的微池装置. 为了检验该微池装置的有效性, 我们分别测试了不同粒径(224, 245和283 nm)单分散聚苯乙烯微球的沉积效果, 并且对其中一种微球(283 nm)进行了不同温度的烘干处理, 检验了烘干温度对该样品表面形貌和光子带隙中心波长的影响. 实验结果表明, 该光子晶体呈面心立方结构, 内部晶格完整, 缺陷较少, 带隙中心波长的实验值与计算值符合得较好. 此外, 烘干处理可以使构成光子晶体的微球发生微观变化, 并导致光子带隙中心波长的蓝移. 相似文献
124.
YANG Jian-Guoa PAN Fu-Youb② SHAO Hongb a 《结构化学》2005,24(11):1286-1289
1 INTRODUCTION Azole derivatives, such as the derivatives of pyra- zole, imidazole, triazole including benzotriazole, te- trazole and indole, have extensive biological activi- ties. They have become the central focus of studies of agricultural chemicals, medicines, plant growth regulating agents and so on[1, 2]. Schiff bases also constitute a good type of biologically active sub- structures. Studies on pyrazole Schiff base-type fun- gicides have been reported[3, 4]. However, some struc- … 相似文献
125.
1 INTRODUCTION There has been increasing interest in the re-search of diode laser-pumped solid-state lasers in re-cent years because of the rapid development of highpower diode lasers. Nd:YAG and Nd:YVO crystalsare commercially available, but limited to low Nd3 (= 1 at.%) doping concentration and to narrow ab-sorption bands near the diode emission wavelengthof 808 nm. Therefore, it is necessary to explore moreefficient crystal materials for diode-pumped solid-state lasers. The alkali … 相似文献
126.
MA Peng-Gaoa ZHANG Ming-Jiea② YANG Qi-Chaob YU Jiu-Gaoa a 《结构化学》2005,24(3):311-314
1 INTRODUCTION Mannich reaction plays an important role in theconstruction of a large variety of nitrogen-containingmolecules, for instance, some pharmaceuticals andnatural products[1, . In practice, phenols and naph- 2]thanols can serve as the substrate of Mannich reac-tion to obtain aminomethylate by the treatment withformaldehyde and amines or nitrogen heterocycliccompounds[3~5]. We report herein the synthesis andcrystal structure of a new nitrogencontaining co… 相似文献
127.
KAN Zi-Guia b CHENG Wen-Dana? WU Dong-Shenga ZHANG Haoa GONG Ya-Jinga ZHU Jinga TONG Hua-Nana a 《结构化学》2005,24(12):1468-1475
1 INTRODUCTION stand the chemical bonding properties and electronic origins of optical transition for solid In(PO3)3, the During the past decades, many indium phosphates crystal energy band and optical response functions have been reported and researched on their conduc- are also calculated. tivity anisotropy, band structure and optical proper- ties[1, . However, to our current knowledge, the com- 2] 2 EXPERIMENTALAND pounds containing alkaline-earth metals are rarely COMPUTATIO… 相似文献
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129.
通过微弧氧化法在Na3PO4+K2Cr2O7电解液中制备了系列铬掺杂二氧化钛薄膜. X射线和扫描电镜显示薄膜的主要晶相为锐钛矿型二氧化钛,且表面为多孔结构. 在可见光照射下,薄膜对降解亚甲基蓝和分解水有着较好的光催化性能,这主要是由铬的掺杂引起的.由于铬的掺杂,一方面在二氧化钛中形成了Cr3+/Cr4+离子对,另一方面在带隙中形成了氧的空位能级. 前者降低了电子-空穴的复合几率,而后者在二氧化钛的禁带中形成了新的能级. 新能级的形成使得由二氧化钛价带跃迁至氧空位能级所需的光子能量减少. 另外探讨了微弧氧化形成掺杂二氧化钛薄膜的机制. 相似文献
130.
A novel hydrochloride quaternary ammonium salt (E)-4-(benzyloxy)-2-(cinnamo- yloxy)-N,N,N-trimethyl-4-oxobutan-1-aminium chloride (C23H29NO4Cl2, Mr = 454.37) has been synthesized via the sequence of acetylation and esterification by using L-carnitine (L-4-N-trimethy- lammonium-3-hydroxybutyric acid, LC) and cinnamic acid as the starting materials, and its crystal structure was determined by single-crystal X-ray diffraction method. The crystal belongs to monoclinic, space group P212121 with a = 10.1670(4), b = 10.4488(4), c = 22.9795(11) ?, V = 2441.18(18) ?3, Z = 4, Dc = 1.236 g/cm3, μ(MoKα) = 0.293 mm?1, F(000) = 960, Flack factor = –0.01(11), the final R = 0.0489 and wR = 0.1550 for 3350 observed reflections (I > 2σ(I)) and R = 0.0953 for all 5648 unique reflections. The crystal structure involves a conjugated system which shows a reverse olefin structure. 相似文献