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991.
芦氟沙星与牛血清白蛋白结合反应的热力学研究 总被引:2,自引:1,他引:2
用荧光光谱和紫外-可见吸收光谱法研究了在模拟人体生理条件下,芦氟沙星与牛血清白蛋白的结合反应,发现芦氟沙星对牛血清白蛋白有较强的荧光猝灭作用,用Stern-Volmer和Lineweaver-Burk方程处理荧光猝灭数据.得到了反应的结合常数、结合热力学性质和结合位置等参数. 相似文献
992.
采用微波辅助提取-液相色谱-氢化物发生-原子荧光光谱法(LC-HG-AFS)联用技术分析了太湖沉积物中砷的形态[亚砷酸(As(III))、二甲基砷酸钠(DMA)、一甲基砷酸二钠(MMA)和砷酸As(V)]。测得沉积物中以无机砷为主,且以As(V)居多。选定以1mol/L的磷酸和0.1mol/L抗坏血酸为提取液,在微波辅助萃取(功率为60W,时间12min)下,萃取率达79.84%~91.57%,回收率在94.78%~107.6%之间。4种砷的形态在0~160μg/L之间时线性良好,检测限为0.6~2.3μg/L,相对标准偏差RSD为1.62%~2.20%。方法具有简便、快速、灵敏的特点。 相似文献
993.
Tom ezanka 《Journal of separation science》2000,23(4):338-342
Analysis of polyunsaturated fatty acids using high performance liquid chromatography–atmospheric pressure chemical ionization mass spectrometry is described. The standard fatty acid methyl esters from 16 to 22 carbons were analyzed by LC‐MS with APCI. The effect of orifice voltage and total carbon atoms versus number of double bonds in each homologue on the mass spectra is discussed. The correction coefficients for homologues from saturated fatty acids to hexaenoic acid are also mentioned. 相似文献
994.
A coupled LC‐GC method for the analysis of carbazole‐type PANH has been developed and evaluated. Group separation and isolation of carbazoles from interfering acridines in a complex sample matrix was accomplished by using a back‐flush technique and an in situ end‐capped dimethylaminopropyl silica column in the HPLC part of the system. On‐line injection of the carbazole fraction into the GC column was performed with a loop‐type interface utilizing concurrent solvent evaporation technique. An LOD of 1–3 pg of individual carbazole compounds was achieved by nitrogen selective detection using an NPD. The method is shown to be robust and is demonstrated by application to personal exposure measurement in an aluminum reduction plant. 相似文献
995.
P. Kolandaivel N. Suba K. Senthilkumar 《International journal of quantum chemistry》2000,76(5):662-669
Balint Kurti's Fourier grid Hamiltonian method is employed to obtain the molecular wave function and equilibrium bond length for H2 and HF molecules. The density functional theory parameter, namely, the chemical hardness (η) value, was determined for some diatomic hydride molecules using this wave function and the results are found to be in good agreement with the values obtained from the ab initio HF–SCF method. A new formula for chemical hardness (η=1/2Dr, where D is the proportionality constant and r is the internuclear distance) is introduced in binding energy and change of hardness equations to determine the chemical hardness and chemical potential values for different bond lengths. The binding energy and change of hardness values are calculated for H2, H, H, HF, HF+, and HF− molecules and the bond stability is discussed. Finally, the concept of an atom in a molecule is examined in the context of DFT parameters and comparison is made between an atom in a molecule and the isolated atom. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 76: 662–669, 2000 相似文献
996.
Muhammad Fawad Khan Muhammad Sulaiman Carlos Andrs Tavera Romero Ali Alkhathlan 《Entropy (Basel, Switzerland)》2021,23(11)
A unipolar electrohydrodynamic (UP-EHD) pump flow is studied with known electric potential at the emitter and zero electric potential at the collector. The model is designed for electric potential, charge density, and electric field. The dimensionless parameters, namely the electrical source number , the electrical Reynolds number , and electrical slip number , are considered with wide ranges of variation to analyze the UP-EHD pump flow. To interpret the pump flow of the UP-EHD model, a hybrid metaheuristic solver is designed, consisting of the recently developed technique sine–cosine algorithm (SCA) and sequential quadratic programming (SQP) under the influence of an artificial neural network. The method is abbreviated as ANN-SCA-SQP. The superiority of the technique is shown by comparing the solution with reference solutions. For a large data set, the technique is executed for one hundred independent experiments. The performance is evaluated through performance operators and convergence plots. 相似文献
997.
Sanjay Khan K. Sudhakar Mohd Hazwan Yusof Prof. Senthilarasu Sundaram 《Chemical record (New York, N.Y.)》2024,24(3):e202300308
The transition to sustainable transportation has fueled the need for innovative electric vehicle (EV) charging solutions. Building Integrated Photovoltaics (BIPV) systems have emerged as a promising technology that combines renewable energy generation with the infra-structure of buildings. This paper comprehensively reviews the BIPV system for EV charging, focusing on its technology, application, and performance. The review identifies the gaps in the existing literature, emphasizing the need for a thorough examination of BIPV systems in the context of EV charging. A detailed review of BIPV technology and its application in EV charging is presented, covering aspects such as the generation of solar cell technology, BIPV system installation, design options and influencing factors. Furthermore, the review examines the performance of BIPV systems for EV charging, focusing on energy, economic, and environmental parameters and their comparison with previous studies. Additionally, the paper explores current trends in energy management for BIPV and EV charging, highlighting the need for effective integration and recommending strategies to optimize energy utilization. Combining BIPV with EV charging provides a promising approach to power EV chargers, enhances building energy efficiency, optimizes the building space, reduces energy losses, and decreases grid dependence. Utilizing BIPV-generated electricity for EV charging provides electricity and fuel savings, offers financial incentives, and increases the market value of the building infrastructure. It significantly lowers greenhouse gas emissions associated with grid and vehicle emissions. It creates a closed-loop circular economic system where energy is produced, consumed, and stored within the building. The paper underscores the importance of effective integration between Building Integrated Photovoltaics (BIPV) and Electric Vehicle (EV) charging, emphasizing the necessity of innovative grid technologies, energy storage solutions, and demand-response energy management strategies to overcome diverse challenges. Overall, the study contributes to the knowledge of BIPV systems for EV charging by presenting practical energy management, effectiveness and sustainability implications. It serves as a valuable resource for researchers, practitioners, and policymakers working towards sustainable transportation and energy systems. 相似文献
998.
999.
This paper presents a novel approach of M-ary baseband pulse amplitude modulated signal processing via a parameter-optimized nonlinear dynamic system.This nonlinear system usually shows the phenomenon of stochastic resonance by adding noise.To thoroughly discuss the signal processing performance of the nonlinear system,we tune the system parameters to obtain a nonlinear detector with optimal performance.For characterizing the output of the nonlinear system,the derivation of the probability of detection error is given by the system response speed and the probability density function of the nonlinear system output.By varying the noise intensity with fixed system parameters,the phenomenon of stochastic resonance is shown and by tuning the system parameters with fixed noise,the probability of detection error is minimized and the nonlinear system is optimized.The detection performance of the two cases is compared with the theoretical probability of detection error,which is validated by numerical simulation. 相似文献
1000.
以室内三轴压缩试验为基础,运用PFC3D离散元软件生成含有不同形状碎石块的1∶1堆积碎石土数值模型,标定得到相应的细观参数(相对误差控制在10%以内)。改变细观参数,定量探讨其与宏观力学参数(粘聚力和内摩擦角)关系,得到细观参数与粘聚力、内摩擦角的细-宏观参数关系式,并对其可靠性进行了验证。研究发现,(1)粘聚力与接触粘结力、颗粒摩擦系数呈线性正相关;同时受粘结力比值M=σc/τc的影响,当M1时,粘聚力随着M的增加而线性增加;M≥4时,粘聚力趋于稳定。(2)内摩擦角与颗粒摩擦系数呈对数关系,与接触粘结力呈抛物线关系。(3)细-宏观参数关系式是在含水率为7%室内试验结果基础上研究得出,将关系式运用到含水率为9%和11%的室内试验结果进行标定验证:依据含水率为9%和11%室内试验得到的c和φ值,运用细-宏观参数关系式计算得到细观参数,经验证其数值-室内试验结果相对误差在10%以内,说明通过细-宏观力学关系式得到的细观参数符合精度要求,关系式可靠。为后续土石混合体数值试验研究者进行细观参数标定工作提供了参考依据。 相似文献