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1 INTRODUCTION Benzimidazole is an interesting heterocyclic ring because it is present in various naturally occurring drugs, such as omeprazole, astemizole and emedastine difumarate[1]. The efficacy of substituted benzimidazoles in the treatment of parasitic infections is well known[2~4], and the pharmacophores in parasitic chemotherapy are established by benzimidazole-substituted moieties. Bis(2-benzimidazoles) and some substituted bis- (benzimi-dazol-2-yl) alkanes have attracted much…  相似文献   
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A complex [Cd(NCS)2(Vim)4] (where Vim=1-vinylimidazole) was synthesized and it′s crystal structure was determined by X-ray diffraction technique. The compound crystallizes in the Monoclinic space group P21/c with the parameters: a=0.858 50(17) nm, b=0.909 90(18) nm, c=1.782 3(4) nm, β=100.14(3)°, V=1.370 5(5) nm3, Z=2. In the structure, each Cd atom is coordinated by four 1-vinylimidazole ligands and a pair of monodentate isothiocyanic groups, affording a compressed octahedral CdN6 core. The NCS- anions are trans and four N atoms from the 1-vinylimidazole ligands define the equatorial plane. From the cyclic voltammogram measurement in H2O, we know that the electrode reaction was a quasi-reversible process. CCDC: 630897.  相似文献   
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基于TGA-FTIR联用技术研究ABS树脂的热氧降解行为   总被引:1,自引:0,他引:1  
采用热失重-傅立叶变换红外光谱(TGA-FTIR)联用技术研究了空气气氛下ABS树脂的热稳定性及热氧降解失重情况。研究了ABS在4个不同升温速率下的失重情况;采用TGA-FTIR联用技术对10℃/min等速升温下ABS失重过程的逸出气体进行分析;采用热分解动力学方法分析ABS的热氧降解过程,计算热分解活化能。结果表明,ABS的TGA曲线有两个失重区间:第一区间是ABS的急剧氧化降解过程,活化能(Ea)为191.8~262.8 kJ.mol-1,第二区间是成炭产物的氧化,Ea约为139.7 kJ.mol-1;升温速率越小,ABS热氧降解速率越慢,交联成炭产物越多,有利于抑制ABS的降解;由FTIR测试和Ea变化发现,热氧降解反应为多步复杂反应,初期时氧化反应和氧化断链同时进行,并以氧化断链反应为主,随着分子链上产生的双键增多发生交联反应,失重率大于80%时开始炭化反应,最终交联炭层发生氧化反应生成CO2。  相似文献   
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用氨水对木材进行预处理, 去除其中的木质素, 再经过高温碳化和活化处理, 得到孔道有序排列的多级孔径三维碳材料, 于150 ℃下熔融吸附硫, 得到高容量 S@C复合电极材料. 扫描电子显微镜(SEM)、 X射线衍射(XRD)、 拉曼光谱及表面吸附实验等测试结果表明, 该碳材料呈现各向异性多级孔径的三维结构, 孔道与树干生长方向平行有序排列; 经过KOH活化后的碳材料孔道内壁上出现较多微孔, 从而具有较大的孔容和比表面积. 以S@C复合材料作正极组装了锂/硫电池, 电化学性能测试结果表明, 电池首次放电比容量达1595 mA·h/g, 接近于硫电极材料的理论比容量1670 mA·h/g.  相似文献   
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本文合成了一种新型配位聚合物[Cu(pa)(vim)2]n(pa为邻苯二甲酸阴离子,vim为1-乙烯基-1H-咪唑),并用x射线单晶衍射仪和元素分析表征了其单晶结构。晶体属单斜晶系,C2/c空间群,晶胞参数分别为:a=1.6527(3) nm, b=0.81800(16) nm, c=1.4463(3) nm, β=113.19(3)°, V=1.7973(7) nm3, Z=4, Dc=1.537 g?cm-3。 [I>2σ(I)]时:R1=0.0476, wR2=0.1235,对所有数据:R1=0.0693, wR2=0.1355。配合物的结构中存在沿着c轴的zigzag聚合链。每个铜原子位于晶体中心,与两个N原子和两个O原子进行配位,形成了扭曲的平面结构。电化学研究表明在配合物中Cu2+/Cu+的氧化还原是一个单电子的准可逆过程。  相似文献   
6.
The title compound Cd(Eim)3Cl2 (Eim = N-ethylimidazole) I has been synthesized and structurally characterized by single-crystal X-ray diffraction. The compound crystallizes in the monoclinic system, space group P2 1 with a = 8.0460(16), b = 29.186(6), c = 8.8960(18)A,β= 100.06(3)°, C15H24CdCl2N6, Mr = 471.71, V = 2056.9(7)A^3 Z = 4, Dc = 1.523 g/cm^3,/1 = 1.330 mm^-1, F(000) = 952, the final R = 0.0455 and wR = 0.0723. The title compound crystallizes with two molecules in the asymmetric unit. Each Cd^II ion is coordinated by three Eim ligands and two Cl anions in a trigonal bipyramidal geometry in two molecules. The weak intermolecular C-H……Cl hydrogen bonds link the molecules into two independent hydrogen-bonded chains running along the c axis. According to the cyclic voltammogram measurement in H2O, the electrode reaction should be a quasi-reversible process.  相似文献   
7.
The title compound I (C22H24MnN10S2, Mr = 547.57) has been synthesized and structurally characterized by single-crystal X-ray diffraction. The compound crystallizes in the monoclinic system, space group P2 1/c with a = 8.6010(17), b = 9.0180(18), c = 17.773(4)A, β = 101.79(3)°, V = 1349.5(5)A^3, Z = 2, Dc = 1.348 g/cm^3,/1 = 0.674 mm^-1, F(000) = 566, the final R = 0.0488 and wR = 0.1289. In the structure, each Mn atom is coordinated by four Vim (Vim = 1-vinylimidazole) ligands and a pair of monodentate isothioeyanic groups, affording a compressed oetahedral MnN6 core.  相似文献   
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