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971.
Cycloparaphenylene (CPP) shows modulated photophysical and electronic properties due to its strained structure and radially oriented π-electron system. Incorporation of CPP into metal-organic frameworks (MOFs) could transfer its extensive properties in solution to porous solids. Moreover, with the unique arrangement of the macrocycles and their interactions with the framework, emerging characteristics are anticipated. As an example of “robust dynamics”, we synthesized the first MOF structure (FDM-1001) with CPP precisely anchored to the ordered framework by employing a [8]CPP-containing linear dicarboxylate linker. Metric relationship between the dynamic macrocycles and the robust backbone creates ideal π-π interactions between them, which leads to an essentially directional arrangement of [8]CPP in the three-dimensional space. Furthermore, the MOF with [8]CPP could be successfully oxidized to generate an infinite array of radicals that show enhanced air stability compared to its molecular analogue. 相似文献
972.
Yan Binggong Kang Lei Kotobuki Masashi He Linchun Liu Bin Jiang Kaiyong 《Journal of Solid State Electrochemistry》2021,25(2):527-534
Journal of Solid State Electrochemistry - We report effectiveness of dopants selected from group 13, such as B, Ga, and In, on the conductivity of Li1.5Al0.5Ge1.5(PO4)3 (LAGP) that is recognized as... 相似文献
973.
974.
Dr. Naixia Lv Jie Yin Wendi Fu Jinrui Zhang Yujun Li Dr. Ding Jiang Dr. Hongping Li Prof. Wenshuai Zhu 《Chemphyschem》2021,22(2):168-177
The rational design of highly active hexagonal boron nitride (h-BN) catalysts at the atomic level is urgent for aerobic reactions. Herein, a doping impurity atom strategy is adopted to increase its catalytic activities. A series of doping systems involving O, C impurities and B, N antisites are constructed and their catalytic activities for molecular O2 have been studied by density functional theory (DFT) calculations. It is demonstrated that O2 is highly activated on ON and BN defects, and moderately activated on CB and CN defects, however, it is not stable on NB and OB defects. The subsequent application in oxidative desulfurization (ODS) reactions proves the ON and C-doped (CB, CN) systems to be good choice for sulfocompounds oxidization, especially for dibenzothiophene (DBT). While the BN antisite is not suitable for such aerobic reaction due to the extremely stable B−O*−B species formed during the oxidation process. 相似文献
975.
Hao Zhuo Xin Chi Mengtian Jiang Prof. Dr. Haibing Xu Prof. Dr. Minghua Zeng 《化学:亚洲杂志》2021,16(9):1165-1170
Attaching AIE-active L1 ([1,1′:2′,1′′:4′′,1′′′-quaterphenyl]-2-yldiphenylphosphane) to AuCl, shortened the distances of P−C bonds to promote electron cloud overlap between AuI and L1 , affords 1 ( L1 AuCl) with aggregation-induced phosphorescence enhancement (AIPE) activity by 3LMCT transitions. Then substituting the coplanar L2 (9-ethynylanthracene) for the Cl− in 1 providing 2 , switches the luminescence to aggregation-caused quenching (ACQ) activity. Furthermore, we restore the performance from ACQ to AIPE by metathesis reactions to transfer 2 into 1 . It is versatile synthetic strategy of reversible transformation between 1 and 2 that switches the luminescence of organogold(I) between AIPE and ACQ through balancing auxiliary ligands around the given metal. 相似文献
976.
Liu Yudong Chen Bing Wang Dengshi Jiang Nan Tan Junkun Fu Jing Wu Baohui Hu Yuanhao Guo Zhihong 《Journal of Thermal Analysis and Calorimetry》2021,144(4):1369-1379
Journal of Thermal Analysis and Calorimetry - The surface tensions of graphene oxide nanofluids of five mass concentrations were measured by the oscillation droplet method in an acoustic levitator.... 相似文献
977.
Zhewen Lu Junqiu Jiang Yi Yang Joshua Lacey Michael J. Brear 《Proceedings of the Combustion Institute》2021,38(1):243-250
This work investigates the oxidation of hydrogen near its second explosion limit in a turbulent flow reactor at pressures of 1 to 8 bar, temperatures of 950 K and an equivalence ratio of 0.035. The concentrations of H2, O2 and H2O are measured along the reactor and simulated using several kinetic models from the literature. These experiments demonstrate evident negative pressure dependence from roughly 1 to 4 bar, with further increases in pressure resuming its positive impact on reaction rates. The simulated and measured species concentrations along the reactor generally agree within a factor of 2.Further investigation is then conducted to measure the rate coefficient of reaction H + O2 (+ M) = HO2 (+M) (R2), which is one of the most sensitive reactions in hydrogen's oxidation chemistry at these conditions. This investigation is conducted by using nitric oxide (NO) as a dopant and measuring the resulting, quasi-steady-state concentrations of NO2. The rate coefficients are obtained at 950 – 1010 K. Combined with literature results, an Arrhenius expression is proposed, = 4.50 × 1020 (T/K)?1.73 [cm6 mole?2 s?1], for the reaction rate at the low-pressure limit over 500 K – 2000 K with N2 as the bath gas. Simulations using the models from the literature with the proposed Arrhenius expression for this reaction then demonstrate improved agreement with the experiments. 相似文献
978.
979.
Chang Su Jin‐Song Gong Jin‐Peng Ye Ji‐Meng He Rui‐Yi Li Min Jiang Yan Geng Yan Zhang Jing‐Hua Chen Zheng‐Hong Xu Jin‐Song Shi 《Macromolecular bioscience》2020,20(9)
Keratin is widely recognized as a high‐quality renewable protein resource for biomedical applications. Despite their extensive existence, keratin resources such as feathers, wool, and hair exhibit high stability and mechanical properties because of their high disulfide bond content. Consequently, keratin extraction is challenging and its application is greatly hindered. In this work, a biological extraction strategy is proposed for the preparation of bioactive keratin and the fabrication of self‐assembled keratin hydrogels (KHs). Based on moderate and controlled hydrolysis by keratinase, keratin with a high molecular weight of approximately 45 and 28 kDa that retain its intrinsic bioactivities is obtained. The keratin products show excellent ability to promote cell growth and migration and are conferred with significant antioxidant ability because of their intrinsically high cysteine content. In addition, without the presence of any cross‐linking agent, the extracted keratin can self‐assemble into injectable hydrogels. The KHs exhibit a porous network structure and 3D culture ability, showing potential in promoting wound healing. This enzyme‐driven keratin extraction strategy opens up a new approach for the preparation of keratin that can self‐assemble into injectable hydrogels for biomedical engineering. 相似文献
980.
Jiang Tian Liu Hannes Hase Sarah Taylor Ingo Salzmann Pat Forgione 《Angewandte Chemie (International ed. in English)》2020,59(18):7146-7153
A library of symmetrical linear oligothiophene was prepared employing decarboxylative cross‐coupling reaction as the key transformation. Thiophene potassium carboxylate salts were used as cross‐coupling partners without the need of co‐catalyst, base, or additives. This method demonstrates complete chemoselectivity and is a comprehensive greener approach compared to the existing methods. The modularity of this approach is demonstrated with the preparation of discreet oligothiophenes with up to 10 thiophene repeat units. Symmetrical oligothiophenes are prototypical organic semiconductors where their molecular electrical doping as a function of the chain length can be assessed spectroscopically. An oligothiophene critical length for integer charge transfer was observed to be 10 thiophene units, highlighting the potential use of discrete oligothiophenes as doped conduction or injection layers in organic electronics applications. 相似文献