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991.
Yu-Xin Guo Xiao-Ye Jin Zhi-Yu Xia Chong Chen Wei Cui Bo-Feng Zhu 《Electrophoresis》2020,41(9):649-656
In this study, a small set of ancestry informative SNPs was selected to differentiate African, European, East and South Asian samples, which was detected by the next-generation sequencing technology. A total of 127 Chinese Shaanxi Han individuals were collected as test samples. No statistically significant linkage disequilibrium of any pair of loci or departure from Hardy–Weinberg equilibrium of each locus was observed in the test population. To evaluate the performance of ancestry assignment using this panel, admixture analysis, principal component analysis, and likelihood ratio calculations were conducted based on the 1000 genome data and test samples. All populations were clustered into four groups, African, European, South and East Asian populations, which were consistent with their geographical origins. The pairwise fixation index (FST) between populations from different continental groups ranged from 0.140 to 0.621 with average 0.415, and the pairwise FST between populations from the same continent ranged from 0.000 to 0.056 with average 0.012. The likelihood ratio results of 125 test individuals indicated that their ancestry components were highly possible from East Asia. In conclusion, this small set of ancestry informative SNPs can be used as a reliable tool to identify and quantify ancestry components of unknown samples. 相似文献
992.
Daoyuan Zheng Yurong Guo Mingxing Zhang Xia Feng Lina Zhu Lijuan Qiu Xiaoning Jin Guangjiu Zhao 《Journal of computational chemistry》2020,41(10):976-985
Organic semiconductors (OSCs) materials are currently under intense investigation because of their potential applications such as organic field-effect transistors, organic photovoltaic devices, and organic light-emitting diodes. Inspired by the selenization strategy can promote anisotropic charge carrier migration, and selenium-containing compounds have been proved to be promising materials as OSCs both for hole and electron transfer. Herein, we now explore the anisotropic transport properties of the series of selenium-containing compounds. For the compound containing Se Se bond, the Se Se bond will break when attaching an electron, thus those compounds cannot act as n-type OSCs. About the different isomer compounds with conjugated structure, the charge transfer will be affected by the stacking of the conjugated structures. The analysis of chemical structure and charge transfer property indicates that Se-containing materials are promising high-performance OSCs and might be used as p-type, n-type, or ambipolar OSCs. Furthermore, the symmetry of the selenium-containing OSCs will affect the type of OSCs. In addition, there is no direct relationship between the R groups with their performance, whether it or not as p-type OSCs or n-types. This work demonstrates the relationship between the optoelectronic function and structure of selenium-containing OSCs materials and hence paves the way to design and improve optoelectronic function of OSCs materials. 相似文献
993.
串联环化及环加成反应是合成具有复杂多环骨架化合物的重要手段[1].重氮酰胺类化合物可发生分子内环化生成isomünchnone中间体,作为1,3-偶极子中间体和亲偶极子发生环加成反应,构建含氧桥环骨架的化合物(Scheme1)[2].金属铑(Ⅱ)催化剂能够与重氮酰胺化合物生成铑卡宾中间体,通过羰基官能团分子内进攻铑卡宾生成isomünchnone中间体,然后和双键或叁键发生串联环化反应,形成氧桥环骨架. 相似文献
994.
Yonggui Liu Dr. Guoyong Luo Dr. Xing Yang Shichun Jiang Prof. Dr. Wei Xue Prof. Dr. Yonggui Robin Chi Prof. Dr. Zhichao Jin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(1):450-456
The aromatic nitrogen atoms of heteroarylaldehydes are activated by carbene catalysts to react with ketone electrophiles. Multi-functionalized cyclic N,O-acetal products are afforded in good to excellent yields and optical purities. Our reaction involves the formation of an unprecedented aza-fulvene-type acylazolium intermediate. A broad range of N-heteroaromatic aldehydes and electron-deficient ketone substrates works effectively in this transformation. Several of the chiral N,O-acetal products afforded through this protocol exhibit excellent antibacterial activities against Ralstonia solanacearum (Rs) and are valuable in the development of novel agrichemicals for plant protection. 相似文献
995.
Dr. Liqin Zhang Prof. Dr. Sai Wang Dr. Zunyi Yang Dr. Shuichi Hoshika Sitao Xie Jin Li Dr. Xigao Chen Dr. Shuo Wan Dr. Long Li Prof. Dr. Steven A. Benner Prof. Dr. Weihong Tan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(2):673-678
Expanding the number of nucleotides in DNA increases the information density of functional DNA molecules, creating nanoassemblies that cannot be invaded by natural DNA/RNA in complex biological systems. Here, we show how six-letter GACTZP DNA contributes this property in two parts of a nanoassembly: 1) in an aptamer evolved from a six-letter DNA library to selectively bind liver cancer cells; and 2) in a six-letter self-assembling GACTZP nanotrain that carries the drug doxorubicin. The aptamer-nanotrain assembly, charged with doxorubicin, selectively kills liver cancer cells in culture, as the selectivity of the aptamer binding directs doxorubicin into the aptamer-targeted cells. The assembly does not kill untransformed cells that the aptamer does not bind. This architecture, built with an expanded genetic alphabet, is reminiscent of antibodies conjugated to drugs, which presumably act by this mechanism as well, but with the antibody replaced by an aptamer. 相似文献
996.
Siquan Zhang Guang Cheng Liping Guo Ning Wang Prof. Bien Tan Prof. Shangbin Jin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(15):6063-6070
Methods to synthesize crystalline covalent triazine frameworks (CTFs) are limited and little attention has been paid to development of hydrophilic CTFs and photocatalytic overall water splitting. A route to synthesize crystalline and hydrophilic CTF-HUST-A1 with a benzylamine-functionalized monomer is presented. The base reagent used plays an important role in the enhancement of crystallinity and hydrophilicity. CTF-HUST-A1 exhibits good crystallinity, excellent hydrophilicity, and excellent photocatalytic activity in sacrificial photocatalytic hydrogen evolution (hydrogen evolution rate up to 9200 μmol g−1 h−1). Photocatalytic overall water splitting is achieved by depositing dual co-catalysts in CTF-HUST-A1, with H2 evolution and O2 evolution rates of 25.4 μmol g−1 h−1 and 12.9 μmol g−1 h−1 in pure water without using sacrificial agent. 相似文献
997.
Shan Jin Manman Zhou Xi Kang Xiaowu Li Wenjun Du Xiao Wei Shuang Chen Dr. Shuxin Wang Prof. Manzhou Zhu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(10):3919-3923
The high-dimensional (that is, three-dimensional (3D)) assembly of nanomaterials is an effective means of improving their properties; however, achieving this assembly at the atomic level remains challenging. Herein, we obtained a novel nanocluster, [Au8Ag57(Dppp)4(C6H11S)32Cl2]Cl (Dppp=1,3-bis(diphenylphosphino)propane) showing a 3D octameric assembly mode involving the kernel penetration of eight complete icosahedral Au@Ag10Au2 units for the first time. The atomically precise structure was determined by single-crystal X-ray diffraction, and further confirmed by thermogravimetric analysis, X-ray photoelectron spectroscopy, and electrospray ionization mass spectrometry measurements. Furthermore, ligand-induced transformation prompted the conversion of [Au8Ag57(Dppp)4(C6H11S)32Cl2]Cl, with complete octameric fusion into [Au8Ag55(Dppp)4(C6H11S)34][BPh4]2, with incomplete octameric fusion. These observations will hopefully facilitate further research on the assembly of M13 nanobuilding blocks. 相似文献
998.
Jiayi Li Liding Wang Zifeng Zhao Xiaoyue Li Xiao Yu Peihao Huo Qionghua Jin Zhiwei Liu Zuqiang Bian Chunhui Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(21):8287-8294
As a kind of photoluminescent material, CuI complexes have many advantages such as adjustable emission, variable structures, and low cost, attracting attention in many fields. In this work, two novel two-coordinate CuI-N-heterocyclic carbene complexes were synthesized, and they exhibit unique dual emission properties, fluorescence and phosphorescence. The crystal structure, packing mode, and photophysical properties under different conditions were systematically studied, proving the emissive mechanism to be the locally excited state of the carbazole group. Based on this mechanism, ultralong room-temperature phosphorescence (RTP) with a lifetime of 140 ms is achieved by selective deuteration of the carbazole group. These results deepen the understanding of the luminescence mechanism and design strategy for two-coordinate CuI complexes, and prove their potential in applications as ultralong RTP materials. 相似文献
999.
Guohai Deng Shujun Lei Dr. Sudip Pan Jiaye Jin Prof. Guanjun Wang Prof. Lili Zhao Prof. Mingfei Zhou Prof. Gernot Frenking 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(46):10487-10500
Homoleptic Group 4 metal carbonyl cation and neutral complexes were prepared in the gas phase and/or in solid neon matrix. Infrared spectroscopy studies reveal that both zirconium and hafnium form eight-coordinate carbonyl neutral and cation complexes. In contrast, titanium forms only the six-coordinate Ti(CO)6+ and seven-coordinate Ti(CO)7. Titanium octacarbonyl Ti(CO)8 is unstable as a result of steric repulsion between the CO ligands. The 20-electron Zr(CO)8 and Hf(CO)8 complexes represent the first experimentally observed homoleptic octacarbonyl neutral complexes of transition metals. The molecules still fulfill the 18-electron rule, because one doubly occupied valence orbital does not mix with any of the metal valence atomic orbitals. Zr(CO)8 and Hf(CO)8 are stable against the loss of one CO because the CO ligands encounter less steric repulsion than Zr(CO)7 and Hf(CO)7. The heptacarbonyl complexes have shorter metal−CO bonds than that of the octacarbonyl complexes due to stronger electrostatic and covalent bonding, but the significantly smaller repulsive Pauli term makes the octacarbonyl complexes stable. 相似文献
1000.
分别采用一步水热法和两步水热法在导电玻璃(FTO)上制备了二氧化钛(TiO2)纳米棒(NR)阵列和TiO2分枝纳米棒(B-NR)阵列。 利用低温化学浴沉积法(CBD)在TiO2纳米棒阵列(NRA)和TiO2分枝纳米棒阵列(B-NRA)基底上沉积Sb2S3纳米粒子(NPs)。 接着分别旋涂聚-3已基噻吩(P3HT)和2,2'7,7'-四-(二甲氧基二苯胺)螺芴(Spiro-OMeTAD)组装成TiO2(NRA)/Sb2S3/P3HT/Spiro-OMeTAD和TiO2(B-NRA)/Sb2S3/P3HT/ Spiro-OMeTAD为光活性层的杂化太阳电池。 结果表明,由TiO2(NRA)/Sb2S3/P3HT/Spiro-OMeTAD复合膜结构组装的杂化太阳电池的光电转换效率(PCE)是2.92%,而由TiO2(B-NRA)/Sb2S3/P3HT/Spiro-OMeTAD复合膜结构组装的杂化太阳电池的PCE提高到了4.67%。 相似文献