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41.
与羟基配位是金属离子的一种重要的存在形式. 我们得到了两种半乳糖醇氯化钆配合物, 其中一种为金属离子与配体为2:1的配合物,钆离子与半乳糖醇的三个羟基及六个水分子配位, 其它水分子以结晶水的形式存在, 氯离子不参加配位;另一种配合物根据红外, 元素分析, 差热热重, 远红外以及太赫兹光谱推测可能是钆离子与两个半乳糖醇分子的六个羟基以及三个水分子配位, 形成1:1配合物. 实验结果说明半乳糖醇与稀土离子之间可以形成多种配合物, 金属离子与糖的羟基存在着复杂的相互作用. 相似文献
42.
A regio-and stereo-selective synthesis of multi-substituted 3-pyrrolines has been developed.The multi-substituted 3-pyrrolines were synthesized in good yields by 1,3-dipolar cycloaddition of methyl 2-(phenylselanyl)acrylate with azomethine ylides,followed by N-acylation and oxidation-elimination of phenylseleno group. 相似文献
43.
Two complemental 2′-phosphorothioate oligo-DNA compounds were used as linker molecules to provide the necessary symmetry-breaking mechanism to direct the assembly of 13 nm Au nanoparticles into aggregates with anisotropic optical properties. 相似文献
44.
A novel photooxidative system for degrading toxic organic pollutants is reported. A new complex of Fe2L3(L = bis[2-hydroxybenzaldehyde]hydrazone) synthesized can efficiently activate hydrogen peroxide (H2O2) to oxidize and mineralize the target complexes rhodamine B (RhB) and methyl orange (MO) in aqueous media under ambient temperature and normal pressure and with visible light irradiation. 相似文献
45.
“超浓盐酸”介质中钯微乳萃取行为 总被引:1,自引:0,他引:1
采用多种分子谱学的表征手段, 研究了萃钯有机相中由于酸的共萃导致溶液微观聚集态结构的变化. 研究结果表明, 与高酸度盐酸水溶液平衡后的TBP载钯有机相微乳水团中形成了浓度远大于常规饱和浓盐酸的“超浓盐酸”; 微乳水团内H+和Cl-的大量聚集增浓对Pd离子的络合配位状态产生影响, H+参与了Pd离子配位状态的转变; 有机相“超浓盐酸”形成后, 使得微乳水团中大量存在的H+有可能参与调控水团中各种HmPdClnz+络合离子配位状态的相对含量. 被H+活化的TBP表面活性剂与钯离子的各种配位状态的匹配程度最终决定了钯的萃取行为. 相似文献
46.
A self-progressing chiral self-assembly form an achiral and C6-symmetric molecule, resulting in a chiral amplification with prolonging the time. The system shows three distinct luminescent colors with the change of time in the same solution system. 相似文献
47.
Chao Xiao Wei-Ye Zhao Da-Yang Zhou Yan Huang Ye Tao Wan-Hua Wua Cheng Yang 《中国化学快报》2015,26(7):817-824
Photochromic diarylethenes were deemed to be one of the most promising molecular building blocks for photoresponsive materials. This review gives a brief summary to the recent progress of studies of diarylethenes in supramolecular systems, focusing on their applications in biological systems, photo-responsive mechanical materials and photo-responsive chemosensors. 相似文献
48.
A series of Nd3+-doped Li3NdxV2àx(PO4)3(x = 0.00, 0.02, 0.05, 0.08 or 0.1) composites are synthesized by the rheological phase reaction method. The XRD results indicate that Nd3+ions have been successfully merged into a lattice structure. Doped samples show good electrochemical performance in high discharge rate and long cycle. In the potential range of 3.0–4.3 V, Li3Nd0.08V1.92(PO4)3exhibits an initial discharge capacity of 115.8 m Ah/g at 0.2 C and retain 80.86% of capacity retention at 2 C in the 51 st cycle.In addition, Li3Nd0.05V1.95(PO4)3holds at 100.4 m Ah/g after 80 cycles at 0.2 C with a capacity retention of92.4%. Finally, the CV test proves that the potential polarization of Li3Nd0.08V1.92(PO4)3decreased compared with the un-doped one. 相似文献
49.
Yu-Hai Liu Jia-Jia Shi Dan-Qing Gao Yun-Long Gao Ran Guo Xiao-Feng Ling Shi-Fu Weng Yi-Zhuang Xu Isao Noda Jin-Guang Wu 《中国化学快报》2015,26(2):182-186
In this paper,2D asynchronous spectra generated by using the DAOSD approach was utilized to probe interactions between Nd~(3+) and pyridinium dissolved in aqueous solution.A series of cross peaks in the resultant 2D asynchronous spectrum confirms the occurrence of intermolecular interaction between Nd~(3+)and pyridinium.However,no coordination occurs between Nd~(3+) and pyridinium.Interaction between πelectron from aromatic system and/electron from lanthanide ions account for the appearance of cross peaks in 2D asynchronous spectra.Because of the interaction,the emission spectrum of pyridinium exhibits a significant change when neodymium perchlorate was introduced into the system. 相似文献
50.
Ling Tang Xiao Juan Wu Bao Min Feng Li Ying Shi Xue Yan Fu Yong Qi Wang Mei Feng Liu 《中国化学快报》2011,22(7):835-838
Two new acetylated kaempferol glycosides were isolated from the seeds of Camellia semiserrata Chi,their structures were elucidated as kaempferol-3-O-[(3-O-acetyl)-α-L-rhamnopyranosyl(1→3)(4-O-acetyl)-α-L-rhamnopyranosyl(1→6)-β-D-glucopyranoside] (1) and kaempferol-3-O-[(2-O-acetyl)-α-L-rhamnopyranosyl(1→3)(4-O-acetyl)-α-L-rhamnopyranosyl(1→6)-β-D-gluco -pyranoside](2) by spectral experiments(including ESI-MS,1D- and 2D-NMR). 相似文献