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991.
Zhaopeng Liu Youming Ni Tantan Sun Wenliang Zhu Zhongmin Liu 《Journal of Energy Chemistry》2021,(3):111-117
Direct converting carbon dioxide into hydrocarbon fuels and value-added chemicals would offer a very attractive approach for efficient utilization of CO2 as a carbon resource.Although,olefins,aromatics and gasoline have been successfully synthesized by CO2 hydrogenation,highly selective conversion of CO2 and H2 into C2+hydrocarbon is still challenging due to a high C-C coupling barrier and inhibiting the production of other long-chain hydrocarbons.Here,we report a composite catalyst made of InZrOx and SSZ-13 molecular sieve(InZrOx+SSZ-13),which exhibits 74.5% propane selectivity at 623 K.The 8-MR micropores and the higher strength of the acid for SSZ-13 benefit the formation of propane.Compared with pure InOx and m-ZrO2 the composite oxide InZrOx containing more oxygen vacancies,exhibits to be more readily reduced by H2 and easier to adsorb and desorb CO2 within the reaction temperature.All those could be beneficial to the activation and conversion of H2 and CO2.The catalytic performance of InZrOx+SSZ-13 in CO2 hydrogenation provides a potential for production of propane. 相似文献
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994.
Improved efficiency and stability of perovskite solar cells with molecular ameliorating of ZnO nanorod/perovskite interface and Mg-doping ZnO 下载免费PDF全文
Despite the advanced efficiency of perovskite solar cells(PSCs),electron transportation is still a pending issue.Here the polymer polyvinylpyrrolidone(PVP)is used to enhance the electron injection,which is thanks to the passivation of the defects at the interface between the ZnO electron transporting layer(ETL)and the perovskite.The application of the PVP layer inhibits the device degradation,and 80%of the primary efficiency is kept after 30 d storage in air condition.Additionally,the efficiency of the device is further enhanced by improving the conductivity and crystallinity of the ZnO ETL via Magnesium(Mg)doping in the ZnO nanorods(ZnO NRs).Moreover,the preparation parameters of the ZnO NRs are optimized.By employing the high-crystallinity ZnO ETL and the PVP layer,the power conversion efficiency(PCE)of the champion device is increased from 16.29%to 19.63%.These results demonstrate the advantages of combining mesoscale manipulation with interface modification and doping together. 相似文献
995.
First-principles analysis of phonon thermal transport properties of two-dimensional WS_2/WSe_2 heterostructures 下载免费PDF全文
The van der Waals(vdW)heterostructures of bilayer transition metal dichalcogenide obtained by vertically stacking have drawn increasing attention for their enormous potential applications in semiconductors and insulators.Here,by using the first-principles calculations and the phonon Boltzmann transport equation(BTE),we studied the phonon transport properties of WS2/WSe2 bilayer heterostructures(WS2/WSe2-BHs).The lattice thermal conductivity of the ideal WS2/WSe2-BHs crystals at room temperature(RT)was 62.98 W/mK,which was clearly lower than the average lattice thermal conductivity of WS2 and WSe2 single layers.Another interesting finding is that the optical branches below 4.73 THz and acoustic branches have powerful coupling,mainly dominating the lattice thermal conductivity.Further,we also noticed that the phonon mean free path(MFP)of the WS2/WSe2-BHs(233 nm)was remarkably attenuated by the free-standing monolayer WS2(526 nm)and WSe2(1720 nm),leading to a small significant size effect of the WS2/WSe2-BHs.Our results systematically demonstrate the low optical and acoustic phonon modes-dominated phonon thermal transport in heterostructures and give a few important guidelines for the synthesis of van der Waals heterostructures with excellent phonon transport properties. 相似文献
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997.
园区综合能源系统(Park integrated energy system,PIES)是满足用户多种用能需求的一种重要途径,但由于内部分布式能源机组出力具有不确定性,且与负荷在时间维度上存在一定的不匹配性,限制了能源利用效率和经济效益的提升.因此,本文首先在构建耦合热电的PIES的基础上,构建了多类型需求响应模型;其... 相似文献
998.
以4,6-二甲基-2-巯基嘧啶、2-巯基苯并噻唑、3-溴丙炔和取代苯甲醛肟为原料,经过亲核取代和Click反应,设计合成了16个含嘧啶、苯并噻唑结构的新型异噁唑衍生物,其收率为21~86%。目标化合物均经过NMR、IR、及HRMS等现代分析方法进行了结构表征,并对化合物进行了体外抗菌活性测试。结果表明其中6个化合物(5b,5d,6b~6h)在浓度为4ug·mL-1时对所测试的大肠杆菌具有明显的抑制活性,5个化合物(5b~5d,5f,6g)在浓度为16ug·mL-1时对所测试的金黄色葡萄球菌有一定的抑制活性,但它们的抑菌活性都低于同浓度下阿莫西林的抑菌活性。该类化合物的合成方法具有反应操作简单和反应条件温和的优点。 相似文献
999.