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991.
Xiu-Feng Hou Peng-Cheng Zhang Shu Liu Hui Wang Yue-Jiang Lin Guo-Xin Jin 《Journal of organometallic chemistry》2008,693(8-9):1462-1468
Five binuclear half-sandwich cobalt complexes, [(η5-C5H4)Co(CO)I2]2SiMe2 (3), [(η5-C5H4)Co(S2C2B10H10)]2SiMe2 (4), [(η5-C5H4)]2Co2(μ2-S2C2B10H10)SiMe2 (5), [(η5-C5H3)CoI2](μ-I)[(η5-C5H3)Co(CO)I](SiMe2)2 (8), [(η5-C5H3)Co(S2C2B10H10)]2(SiMe2)2 (9), were successfully synthesized in moderate yield by the reactions of corresponding ligands, (C5H5)2SiMe2 (1) and (C5H4)2(SiMe2)2 (6), respectively. The molecular structures of 3, 5, 6, 8 and 9 was determined by X-ray crystallographic analysis, which distinctly depict various molecular structures containing the Cp rings and the metal centers with halide or 1,2-dicarba-closo-dodecaborane-1,2-dithiolato ligands. For the (η5-C5H4)2SiMe2 complexes, coordination of the fragments CpCo favors a exo conformation. With the rigid structure of the di-bridged ligand (C5H4)2(SiMe2)2, only cis isomers of the corresponding (η5-C5H3)2(Si2Me2)2 complexes are formed. All the complexes have been well characterized by elemental analysis, NMR and IR spectra. 相似文献
992.
Shaolei Ding Yingbo Shi Baochao Yang Min Hou Dr. Haibing He Prof. Dr. Shuanhu Gao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(2):e202214873
We report herein the asymmetric total synthesis of periglaucines A–C, N,O-dimethyloxostephine and oxostephabenine. The key strategies used include: 1) a RhI-catalyzed regio- and diastereoselective Hayashi-Miyaura reaction to connect two necessary fragments; 2) an intramolecular photoenolization/Diels–Alder (PEDA) reaction to construct the highly functionalized tricyclic core skeleton bearing a quaternary center; 3) a bio-inspired intramolecular Michael addition and transannular acetalization to generate the aza[4.4.3]propellane and the tetrahydrofuran ring. 相似文献
993.
Xingyue He Qing Wu Chen Hou Min Hu Qigang Wang Xia Wang 《Angewandte Chemie (International ed. in English)》2023,62(15):e202218766
Some cellular enzymatic pathways are located within a single organelle, while most others involve enzymes that are located within multiple compartmentalized cellular organelles to realize the efficient multi-step enzymatic process. Herein, bioinspired by enzyme-mediated biosynthesis and biochemical defense, a compartmented nanoreactor (Burr-NCs@GlSOD) was constructed through a self-confined catalysis strategy with burr defect-engineered molybdenum disulfide/Prussian blue analogues (MoS2/PBA) and an interfacial diffusion-controlled hydrogel network. The specific catalytic mechanism of the laccase-like superactivity induced hydrogelation and cascade enzyme catalytic therapy were explored. The confined hydrogelation strategy introduces a versatile means for nanointerface functionalization and provides insight into biological construction of simulated enzymes with comparable activity and also the specificity to natural enzymes. 相似文献
994.
Dr. Tingting Xu Dr. Xudong Hou Dr. Yi Han Dr. Haipeng Wei Dr. Zhengtao Li Prof. Dr. Chunyan Chi 《Angewandte Chemie (International ed. in English)》2023,62(38):e202304937
Polycyclic hydrocarbons consisting of two or more directly fused antiaromatic subunits are rare due to their high reactivity. However, it is important to understand how the interactions between the antiaromatic subunits influence the electronic properties of the fused structure. Herein, we present the synthesis of two fused indacene dimer isomers: s-indaceno[2,1-a]-s-indacene ( s -ID ) and as-indaceno[3,2-b]-as-indacene ( as -ID ), containing two fused antiaromatic s-indacene or as-indacene units, respectively. Their structures were confirmed by X-ray crystallographic analysis. 1H NMR/ESR measurements and DFT calculations revealed that both s -ID and as -ID have an open-shell singlet ground state. However, while localized antiaromaticity was observed in s -ID , as -ID showed weak global aromaticity. Moreover, as -ID exhibited a larger diradical character and a smaller singlet-triplet gap than s -ID . All the differences can be attributed to their distinct quinoidal substructures. 相似文献
995.
Xiao Ling Guo Yun Yin Niu Qing Li Wang Ben Lai Wu Hong Yun Zhang Hong Wei Hou Yi Han Ling Fang Wang 《中国化学快报》2008,19(5):604-606
A novel co-ordination polymer based on IB metal thiocyanates, [Ag2(NCS)2(4,4'-bipy)]. (1)(4,4'-bipy = 4,4'-bispyridine), has been synthesized by the pre-assembly method and characterized by X-ray crystallography. The complex exists as a three- dimensional network consisting of (AgSCN). undulating layers linked by 4,4'-bipy bridges. 相似文献
996.
Highly sensitive amperometric detection of dihydronicotinamide adenine dinucleotide (NADH) by using novel synthesized carbon nanofibers (CNFs) without addition of any mediator has been proposed. The CNFs were prepared by combination of electrospinning technique with thermal treatment method and were applied without any oxidation pretreatment to construct the electrochemical sensor. In amperometric detection of NADH, a linear range up to 11.45 μM with a low detection limit of 20 nM was obtained with the CNF‐modified carbon paste electrode (CNF‐CPE). Good selectivity was exhibited for the simultaneous detection of NADH and its common interferent of ascorbic acid (AA) by differential pulse voltammogram. The attractive electrochemical performance and the versatile preparation process of the CNF‐CPE made it a promising candidate for designing effective NADH sensor. 相似文献
997.
Jiangbo She Chao Gao Kai Cui Chaoqi Hou Wei Zhao Wei Wei Bo Peng 《Structural chemistry》2008,19(6):905-910
A novel neodymium pentafluoropropionate binuclear complex, Nd(C2F5COO)3 · Phen (Phen: 1,10-phenanthroline), was synthesized and characterized by single-crystal X-ray diffraction, elemental analysis,
FT-IR spectra, UV–Vis–NIR absorption, and PL spectra. Single-crystal data show that the complex bears centrosymmetric dinuclear
structure with a planar ligand configuration. Four carboxylato groups act as η2-chelate-μ2-carboxylato-k1O:k1O′-bridge-ligands, the other two occupy the terminal position as monodentate ligands. At the same time, the C–O distances
appear averaged which indicate the three atoms of carboxylato forming electron-conjugate system. Hydrogen bond and π–π-stacking
link the binuclear to two-dimensional sheet. Optical spectra exhibit the complex possesses typical Nd(III) ion absorption
and photoluminescence emission. 相似文献
998.
Coulter–Matthews (CM) bent functions are from to defined by , where and (α,2n)=1. It is not known if these bent functions are weakly regular in general. In this paper, we show that when n is even and α=n+1 (or n−1), the CM bent function is weakly regular. Moreover, we explicitly determine the dual of the CM bent function in this case. The dual is a bent function not reported previously. 相似文献
999.
Lijiao Ma Prof. Shaoqing Zhang Junzhen Ren Guanlin Wang Jiayao Li Zhihao Chen Huifeng Yao Prof. Jianhui Hou 《Angewandte Chemie (International ed. in English)》2023,62(5):e202214088
To modulate the miscibility between donor and acceptor materials both possessing fully non-fused ring structures, a series of electron acceptors (A4T-16, A4T-31 and A4T-32) with different polar functional substituents were synthesized and investigated. The three acceptors show good planarity, high conformational stability, complementary absorption and energy levels with the non-fused polymer donor (PTVT-BT). Among them, A4T-32 possesses the strongest polar functional group and shows the highest surface energy, which facilitates morphological modulation in the bulk heterojunction (BHJ) blend. Benefiting from the proper morphology control method, an impressive power conversion efficiency (PCE) of approaching 16.0 % and a superior fill factor over 0.795 are achieved in the PTVT-BT : A4T-32-based organic photovoltaic cells with superior photoactive materials price advantage, which represent the highest value for the cells based on the non-fused blend films. Notably, this cell maintains ≈84 % of its initial PCE after nearly 2000 h under the continuous simulated 1-sun-illumination. In addition, the flexible PTVT-BT : A4T-32-based cells were fabricated and delivered a decent PCE of 14.6 %. This work provides an effective molecular design strategy for the non-fused non-fullerene acceptors (NFAs) from the aspect of bulk morphology control in fully non-fused BHJ layers, which is crucial for their practical applications. 相似文献
1000.
Dr. Ying-Jie Sun Wen-Da Chen Dr. Ji Liu Jun-Jin Li Yu Zhang Wei-Qi Cai Prof. Li Liu Xin-Jing Tang Jian Hou Prof. Ming Wang Prof. Liang Cheng 《Angewandte Chemie (International ed. in English)》2023,62(5):e202212413
The CRISPR/Cas system is one of the most powerful tools for gene editing. However, approaches for precise control of genome editing and regulatory events are still desirable. Here, we report the spatiotemporal and efficient control of CRISPR/Cas9- and Cas12a-mediated editing with conformationally restricted guide RNAs (gRNAs). This approach relied on only two or three pre-installed photo-labile substituents followed by an intramolecular cyclization, representing a robust synthetic method in comparison to the heavily modified linear gRNAs that often require extensive screening and time-consuming optimization. This tactic could direct the precise cleavage of the genes encoding green fluorescent protein (GFP) and the vascular endothelial growth factor A (VEGFA) protein within a predefined cutting region without notable editing leakage in live cells. We also achieved light-mediated myostatin (MSTN) gene editing in embryos, wherein a new bow-knot-type gRNA was constructed with excellent OFF/ON switch efficiency. Overall, our work provides a significant new strategy in CRISPR/Cas editing with modified circular gRNAs to precisely manipulate where and when genes are edited. 相似文献