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11.
合成了1-(2-吡啶甲基)-1,2,4-三唑(L)并研究了其与有机锡和羰基钼(钨)的配位反应,合成了通过三唑4位氮原子以单齿形式配位的有机锡衍生物L2SnR2Cl2(R=Me,n-Bu或Ph)和羰基金属配合物LM(CO)5(M=Mo或W),以及N,N螯合双齿配位的四羰基金属配合物LM(CO)4。当用氯化苄处理L时,制得了相应的三唑盐,该盐用氧化银处理后与M(CO)5THF或M(CO)4(NHC5H10)2(NHC5H10为哌啶)反应,得到了基于三唑的氮杂环卡宾衍生物L′M(CO)5和L′M(CO)4(L′=1-(2-吡啶甲基)-4-苄基-1,2,4-三唑-5-碳烯)。X-射线单晶衍射分析表明,在L′M(CO)5中氮杂环卡宾配体L′表现为通过卡宾碳配位的单齿配体;而在L′M(CO)4中,L′表现为通过卡宾碳和吡啶氮原子配位的螯合[C,N]双齿配体。  相似文献   
12.
通过一步溶剂热法合成ZnO/BiOI纳米复合材料,在Bi(NO33·6H2O、KI、ZnO和乙二醇(EG)溶剂中,制备出的样品尺寸和形貌采用X射线粉末衍射(XRD)、场发射扫描电镜(FESEM)、高分辨透射电镜(HRTEM)、紫外-可见漫反射光谱(DRS)、X射线光电子能谱(XPS)、N2吸附-脱附等,对实验所得产物的组成、结构及光学性质等进行表征。以染料罗丹明B(RhB)水溶液和气态乙醛作为降解对象,采用BiOI、ZnO/BiOI和ZnO微纳材料作为光催化剂,通过对BiOI、ZnO/BiOI和ZnO微纳材料在可见光下光催化降解染料罗丹明B(RhB)水溶液和气态乙醛,结果表明多孔微纳材料的ZnO/BiOI具有更高的降解效率,实验表明多孔微纳材料的ZnO/BiOI具有更高的氧空位浓度,因此使其催化活性增强,讨论了其可能的催化活性机理。  相似文献   
13.
An efficient and convenient approach to the synthesis of 3,3,6,6-tetramethyl-9-aryl-1,8-dioxo-octahydroxanthene derivatives using p-dodecylbenzenesulfonic acid (DBSA) as the catalyst (10 mol.%) under ultrasound irradiation is described. This method provides several advantages such as environment friendliness, high yields and simple work-up procedure. In addition, water was chosen as a green solvent.  相似文献   
14.
The migration and predation of grasshoppers inspire the grasshopper optimization algorithm (GOA). It can be applied to practical problems. The binary grasshopper optimization algorithm (BGOA) is used for binary problems. To improve the algorithm’s exploration capability and the solution’s quality, this paper modifies the step size in BGOA. The step size is expanded and three new transfer functions are proposed based on the improvement. To demonstrate the availability of the algorithm, a comparative experiment with BGOA, particle swarm optimization (PSO), and binary gray wolf optimizer (BGWO) is conducted. The improved algorithm is tested on 23 benchmark test functions. Wilcoxon rank-sum and Friedman tests are used to verify the algorithm’s validity. The results indicate that the optimized algorithm is significantly more excellent than others in most functions. In the aspect of the application, this paper selects 23 datasets of UCI for feature selection implementation. The improved algorithm yields higher accuracy and fewer features.  相似文献   
15.
In modem organic chemical research, 4H-benzo-[b]-pyran and their derivatives have attracted strong interest due to their useful biological and pharmacological properties. Herein, we report a clean one-pot synthesis of 2-amino-3-cyano-4-aryl-7,7-dimethyl-5-oxo-4H-5,6,7,8-tetrahydro-benzo-[b]-pyrans from aromatic aldehyde, malononitrile and 5,5-dimethyl-1,3-cyclohexadione using hexadecyl trimethyl ammonium bromide (HTMAB) as the catalyst. This method provides several advantages such as high yield, simple work-up procedure and environmental friendliness. All the products were characterized by 1H NMR and IR analyses.  相似文献   
16.
<正>1 Experimental section 1.1 General information All manipulations of air- and/or moisture-sensitive compounds were performed under nitrogen atmosphere using standard Schlenk techniques. 1H NMR and 13 C NMR spectra were recorded on a Varian XL-300 MHz spectrometer with TMS as the internal standard. Mass spectra were obtained using a HP5959 A spectrometer. IR spectra were recorded using a Nicolet AV-360 spectrometer. Elemental analysis was performed by the Analytical Laboratory of Shanghai Institute of Organic Chemistry(CAS). Mn, Mw, and Mw/Mn values of polymers were determined with a Waters Alliance GPC 2000 series at  相似文献   
17.
以鲱鱼精脱氧核糖核酸(Herring sperm DNA)为研究对象,利用紫外光(UV,200~275 nm,66.4 Lx)激发纳米TiO2发生光催化作用介导产生羟基自由基(Hydroxyl radical,.OH),探讨.OH引发DNA氧化损伤特性。采用凝胶电泳和高效液相色谱(HPLC)分析法跟踪DNA损伤历程;应用电子自旋共振(Electron spinresonance,ESR)及分光光度法跟踪损伤过程氧化物种及H2O2相对浓度的变化;运用生物标准样8-羟基脱氧鸟苷(8-Hydroxy-2’-deoxyguanosine,8-OHdG)为内标物,通过HPLC分析DNA损伤产物,研究DNA损伤机理。结果表明,较单纯UV辐照或暗光(Dark)催化条件,DNA浓度10 mg/L,TiO2浓度1.5 g/L、pH 7~8,紫外光激发纳米TiO2介导产生.OH引发DNA损伤程度最大;DNA损伤为.OH氧化历程,并伴随有深度氧化过程;DNA结构中鸟嘌呤最易氧化损伤,8-OHdG为DNA氧化损伤中间产物及鸟嘌呤氧化损伤的特异产物。  相似文献   
18.
A new oxadiazole-containing cyclotriphosphazene, namely, hexakis-(4-(5-phenyl-1,3,4-oxazodiazol-2-yl)-phenoxy)-cyclotriphosphazene (HPCP) was synthesized. Single-crystal nano- and microbelts of HPCP were self-assembly via two simple solution methods. The shapes of the as-prepared nano- and microstructures can be readily controlled by varying the solvent and aging time in the self-assembly process. A growth mechanism was proposed for the formation of the 1D morphological structures. Crystal structure analysis demonstrated that the overlap between the aryl units attached to the cyclotriphosphazene backbone forms effective intermolecular π-π linking for crystal growth. Electronic and optical properties of the as-prepared nano- and microstructures are investigated.  相似文献   
19.
由2-硝基-1,4-对苯二甲酸和4,4'-联吡啶作为起始原料合成了4个金属银的配位聚合物,{[Ag(4,4'-bipy)]·2-Hnbdc·2H2O·CH3OH}n (1),{[Ag(4,4'-bipy)(2-Hnbdc)]}n (2),{[Ag2(4,4'-bipy)2(2-nbdc)]·2H2O}n (3),和{[Ag2(4,4'-bipy)2(2-nbdc)(H2O)]·2H2O}n (4)。通过IR、元素分析、TG、UV和荧光光谱以及粉末衍射等手段,对配合物进行了表征和性质研究。单晶衍射分析显示,配合物1为1D阴-阳离子型聚合物,配合物2为1D双链结构,且结构中不存在溶剂分子。配合物34均为1D链状结构。结构的多样性主要是由配体构象、硝基对苯二甲酸的配位模式以及弱作用(如π-π堆积、Ag…Ag作用以及氢键等)导致的。结构的不同也使得它们的稳定性、紫外吸收以及荧光光谱存在着差异。  相似文献   
20.
报道了以十二烷基苯磺酸(DBSA)为催化剂,芳醛、丙二腈和5,5-二甲基-1,3-环己二酮为原料于水中一步生成2-氨基-3-氰基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃.该方法具有产率高、操作简便、对环境友好、催化剂可重复使用等优点.  相似文献   
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