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991.
台风对沿海地区气溶胶光学特性的影响分析 总被引:3,自引:0,他引:3
利用CE317太阳辐射计对2005年第19号台风登陆前后期问(9月29 H至10月6日)进行观测实验,采用Langley法分析台风对中国大陆沿海地区气溶胶光学特性的影响.指出台风过后气溶胶光学特性明显发生改变,气溶胶大粒子数增多,小粒子数减小.气溶胶光学厚度、Angstr(o)m波长指数α和大气混浊度系数β为测量期间最低分别为0.132(550 nm处),0.861和0.079.同时利用实验期间APS3321空气动力学粒度仪分析的气溶胶单位体积数粗细质粒所占比重、气溶胶粒子尺度谱分布和实测的日际气溶胶粒子数浓度对实验分析结果.α,β进行对比,发现它们之间的一致性很好. 相似文献
992.
993.
Small world effects in the harmonious unifying hybrid preferential model (HUHPM) networks are studied both numerically and analytically. The idea and method of the HUHPM is applied to three typical examples of unweighted BA model, weighted BBV model, and the TDE model, so-called HUHPM-BA, HUHPM-BBV and HUHPM-TDE networks. Comparing the HUHPM with current typical models above, it is found that the HUHPM networks has the smallest average path length and the biggest average clustering coefficient. The results demonstrate that the HUHPM is more suitable not only for the un-weighted models but also for the weighted models. 相似文献
994.
Using the particle-in-cell simulations,we report an efficient scheme to generate a slow wave structure in the electron density of a plasma waveguide,based on the array laser-plasma interaction.The spatial distribution of the electron density of the plasma waveguide is modulated via effective control of the super-Gaussian index and array pattern code of the lasers.A complete overview of the holding time,and the bearable laser's intensity of the electron density structure of the plasma waveguide,is obtained.In addition,the holding time of the slow wave structure of the plasma waveguide is also controlled by adjusting the frequency of the array laser beam.Finally,effects due to ion motion are discussed in detail. 相似文献
995.
Minjian Ma Xiaoxia Yang Jinshuo Qiao Wang Sun Zhenhua Wang Kening Sun 《Journal of Energy Chemistry》2021,(5):209-222
Carbon-fueled solid oxide fuel cells(CF-SOFCs)can electrochemically convert the chemical energy in carbon into electricity,which demonstrate both superior electrical efficiency and fuel utilisation compared to all other types of fuel cells.However,using solid carbon as the fuel of SOFCs also faces some challenges,the fluid mobility and reactive activity of carbon-based fuels are much lower than those of gaseous fuels.Therefore,the anode reaction kinetics plays a crucial role in determining the electrochemical performance of CF-SOFCs.Herein,the progress of various anodes in CF-SOFCs is reviewed from the perspective of material compositions,electrochemical performance and microstructures.Challenges faced in developing high performance anodes for CF-SOFCs are also discussed. 相似文献
996.
Mengdan Qiao Fei Li Xianze Meng Meiling Wang Hanyu Zhu Zhiyong Ji Yingying Zhao Jie Liu Shizhao Wang Xiaofu Guo Jingtao Bi Junsheng Yuan 《Molecules (Basel, Switzerland)》2022,27(17)
The microstructure of a mixed KCl and K2SO4 aqueous solution was studied using X-ray scattering (XRS), Raman spectroscopy, and molecular dynamics simulation (MD). Reduced structure functions [F(Q)], reduced pair distribution functions [G(r)], Raman spectrum, and pair distribution functions (PDF) were obtained. The XRS results show that the main peak (r = 2.81 Å) of G(r) shifted to the right of the axis (r = 3.15 Å) with increased KCl and decreased K2SO4. The main peak was at r = 3.15 Å when the KCl concentration was 26.00% and the K2SO4 concentration was 0.00%. It is speculated that this phenomenon was caused by the main interaction changing, from K-OW (r = 2.80 Å) and OW-OW (r = 2.80 Å), to Cl−-OW (r = 3.14 Å) and K+-Cl− (r = 3.15 Å). According to the trend of the hydrogen bond structure in the Raman spectrum, when the concentration of KCl was high and K2SO4 was low, the destruction of the tetrahedral hydrogen bond network in the solution was more serious. This shows that the destruction strength of the anion to the hydrogen bond network structure in solution was Cl− > SO42−. In the MD simulations, the coordination number of OW-OW decreased with increasing KCl concentration, indicating that the tetrahedral hydrogen bond network was severely disrupted, which confirmed the results of the Raman spectroscopy. The hydration radius and coordination number of SO42− in the mixed solution were larger than Cl−, thus revealing the reason why the solubility of KCl in water was greater than that of K2SO4 at room temperature. 相似文献
997.
Mantong Li Feng Jiang Liangyi Xue Cheng Peng Zhengzheng Shi Zheng Zhang Jia Li Yupeng Pan Xinya Wang Chunqiong Feng Dongfang Qiao Zhenzhong Chen Qizhi Luo Xuncai Chen 《Molecules (Basel, Switzerland)》2022,27(21)
Cancer is a leading cause of death worldwide, with an increasing mortality rate over the past years. The early detection of cancer contributes to early diagnosis and subsequent treatment. How to detect early cancer has become one of the hot research directions of cancer. Tumor biomarkers, biochemical parameters for reflecting cancer occurrence and progression have caused much attention in cancer early detection. Due to high sensitivity, convenience and low cost, biosensors have been largely developed to detect tumor biomarkers. This review describes the application of various biosensors in detecting tumor markers. Firstly, several typical tumor makers, such as neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), prostate-specific antigen (PSA), squamous cell carcinoma antigen (SCCA), carbohydrate, antigen19-9 (CA19-9) and tumor suppressor p53 (TP53), which may be helpful for early cancer detection in the clinic, are briefly described. Then, various biosensors, mainly focusing on electrochemical biosensors, optical biosensors, photoelectrochemical biosensors, piezoelectric biosensors and aptamer sensors, are discussed. Specifically, the operation principles of biosensors, nanomaterials used in biosensors and the application of biosensors in tumor marker detection have been comprehensively reviewed and provided. Lastly, the challenges and prospects for developing effective biosensors for early cancer diagnosis are discussed. 相似文献
998.
999.
Huihuan Wu Sha Tu Zewei Zhuo Rui Jiang Ruijie Zeng Qi Yang Qizhou Lian Weihong Sha Hao Chen 《Molecules (Basel, Switzerland)》2023,28(1)
Ulcerative colitis is a chronic inflammatory bowel disorder that is hard to cure once diagnosed. Bisdemethoxycurcumin has shown positive effects on inflammatory diseases. However, the underlying bioactive interaction between bisdemethoxycurcumin and ulcerative colitis is unclear. The objective of this study was to determine the core target and potential mechanism of action of bisdemethoxycurcumin as a therapy for ulcerative colitis. The public databases were used to identify potential targets for bisdemethoxycurcumin and ulcerative colitis. To investigate the potential mechanisms, the protein-protein interaction network, gene ontology analysis, and Kyoto encyclopedia of genes and genomes analysis have been carried out. Subsequently, experimental verification was conducted to confirm the findings. A total of 132 intersecting genes of bisdemethoxycurcumin, as well as ulcerative coli-tis-related targets, were obtained. SRC, EGFR, AKT1, and PIK3R1 were the targets of highest potential, and the PI3K/Akt and MAPK pathways may be essential for the treatment of ulcerative colitis by bisdemethoxycurcumin. Molecular docking demonstrated that bisdemethoxycurcumin combined well with SRC, EGFR, PIK3R1, and AKT1. Moreover, the in vitro experiments suggested that bisdemethoxycurcumin might reduce LPS-induced pro-inflammatory cytokines levels in RAW264.7 cells by suppressing PI3K/Akt and MAPK pathways. Our study provided a comprehensive overview of the potential targets and molecular mechanism of bisdemethoxycurcumin against ulcerative colitis. Furthermore, it also provided a theoretical basis for the clinical treatment of ulcerative colitis, as well as compelling evidence for further study on the mechanism of bisdemethoxycurcumin in the treatment of ulcerative colitis. 相似文献
1000.
Zhe-Cheng Wei Qiao Wang Li-Jing Min Joanna Bajsa-Hirschel Charles L. Cantrell Liang Han Cheng-Xia Tan Jian-Quan Weng Yu-Xin Li Na-Bo Sun Stephen O. Duke Xing-Hai Liu 《Molecules (Basel, Switzerland)》2023,28(1)
Natural products are a source for pesticide or drug discovery. In order to discover lead compounds with high fungicidal or herbicidal activity, new niacinamide derivatives derived from the natural product niacinamide, containing chiral flexible chains, were designed and synthesized. Their structures were confirmed by 1H NMR, 13C NMR and HRMS analysis. The fungicidal and herbicidal activities of these compounds were tested. The fungicidal activity results demonstrated that the compound (S)-2-(2-chloronicotinamido)propyl-2-methylbenzoate (3i) exhibited good fungicidal activity (92.3% inhibition) against the plant pathogen Botryosphaeria berengriana at 50 μg/mL and with an EC50 of 6.68 ± 0.72 μg/mL, which is the same as the positive control (fluxapyroxad). Compound 3i was not phytotoxic and could therefore be used as a fungicide on crops. Structure-activity relationships (SAR) were studied by molecular docking simulations with the succinate dehydrogenase of the fungal mitochondrial respiratory chain. 相似文献