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61.
Immobilization of HX:[Hmim]X as Halogenating Agent, Recyclable Catalyst and Medium for Conversion of Alcohols to Alkyl Halides 总被引:2,自引:0,他引:2
HX is immobilized by reaction of halogen acid with methylimidazole, and the formed ionic liquid [Hmim]X was used as halogenating agent, catalyst as well as medium for conversion of alcohols to alkyl halides. Excellent yields were obtained. The halides produced could be easily separated from the reaction mixture via simple decantation, and the ionic liquid [Hmim]X could be regenerated conveniently by adding equivalent of halogen acids followed by removal of water. 相似文献
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Hui Wen Yi-rong Liu Kang-ming Xu Teng Huang Chang-jin Hu Wei-jun Zhang Wei Huang 《化学物理学报(中文版)》2013,(6):729-738,I0004
Alkali halide clusters are interesting model systems that can provide information about how crystal properties evolve. To study these properties, a high-resolution atmospheric pressure inlet time-of-flight mass spectrometry (APi-TOF-MS) study of the sequential sodium halides series, C1-(NaC1)n and Br-(NaBr)m, has been reported, and the viability of the APi-TOF- MS equipped with an electrospray ionization source in determining cluster compositions has been demonstrated. The isotopic patterns were well resolved, as n=4 and 7 were determined to be the magic numbers for C1-(NaC1)n clusters, which were particularly abundant in the mass spectra. A global minimum search based on density functional theory enabled basin hopping yield the most stable structures for the mentioned series. The structures exhibit several distinct motifs which can be roughly categorized as linear chain, rock salt, and hexag- onal ring. This work provides an effective way to discover and elucidate the nonstoichiometry sodium halide clusters. These clusters possess very high vertical detachment energies and are generally called as superhalogens, which play important roles in chemistry because they are widely used in the synthesis of new classes of charge-transfer salts. 相似文献
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The catalytic activity of a series of indenylnickel(Ⅱ) halides: (1-R-Ind)Ni(PPh3)X (R=ethyl, cyclopentyl and benzyl, while X=Cl, Br and I), towards styrene polymerization was studied in the presence of NaBPh4 and PPh3. The catalytic property of these halides was related to the substituent group on the indenyl ligand and the halogen atom bonded to the metal atom. Among them, the (1-Et-Ind)Ni(PPh3)Cl/NaBPha/PPh3 system showed the highest activity for the polymerization of styrene, and the polystyrene obtained was a syndio-rich (rr triad) atactic polymer with Mn values in the range of 103--104. The mechanism of the styrene polymerization initiated by the (1-Et-Ind)Ni(PPh3)Cl/NaBPha/PPh3 system was studied. 相似文献
65.
ZHAO Zhen-Qiana b LIU Xia CHEN Wen-Tonga LI Yana WU A-Qinga ZENG Hui-Yia GUO Guo-Conga② HUANG Jin-Shuna a 《结构化学》2006,25(2):159-162
1 INTRODUCTION The alkali metal chalcogenide halides have at- tracted considerable interests since last decades due to their abundant interesting structures and good properties with potential applications[1~8]. The type of M3QX (M = alkali metal, Q = chalcogenide; X = halide) compounds has been well studied. The known structure types of these compounds are only ternary alkali metal oxide halides and can be classified as the following species: 1) cubic anti-perovskite type, such as K3O… 相似文献
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复合卤化物中钐价态的异常变化及其稳定性孙淑清,石春山(中国科学院长春应用化学研究所稀土化学与物理开放实验室长春130022)关键词钐,价态,复合卤化物,光谱Sm2+离子在红区和红外区可以产生4f6组态内的f-f跃迁锐线发射和4f55d组态的d-f跃迁... 相似文献
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本文论证了由于Cl^-是硬碱而I^-是软碱根据电解质迁移自由能△Gt^o(MCl)、△Gt^o(MBr)和△Gt^o(MI)作图外推计算单独离子标准迁移自由能△Gt^o(i)的方法是不正确的。提出了根据△Gt^o(MF)和△Gt^o(MCl)的作图外推法, 对于20wt%和40wt%乙醇-水混合溶剂, 所计算的△Gt^o(i)与碱金属氯化物的△Gt^o(MCl)作图歪推法所计算的值比较一致。用离子选择电极电位法系统地测定了△Gt^o(NaX)(X=F^-、Cl^-、Br^-、I^-)、△Gt^o(LiCl)和△Gt^o(HCl)。 相似文献