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991.
Meng-Yu Tsai Yvonne Wu Leia Fan Elaine Jian Jason Lin Jessica Tseng Andy Tseng Renee Wan Eric Lee 《Electrophoresis》2022,43(3):495-500
A simple analytical formula is obtained for the diffusiophoresis of a dielectric fluid droplet in symmetric binary electrolyte solutions under Debye–Hückel approximation valid for weakly charged droplets. The chemiphoresis is found to yield negative mobilities most of the time for droplets of constant surface charge density, which implies that the droplets tend to move away from the source releasing ionic chemicals. This is undesirable in some practical applications like drug delivery with liposomes in terms of conveying the drug-carrying liposomes to the desired area in the human body releasing specific ionic chemicals utilizing the self-guiding nature of diffusiophoresis. The further involvement of the electrophoresis component, however, may change the scenario via the oriented electric field generated by the induced diffusion potential. The lesson here is that while the impact of the chemiphoresis component is determined by nature and uncontrollable, the electrophoresis component serves as an artificially adjustable factor via choosing droplets with the surface charge of appropriate sign in practical applications. The results here have potential use in practical applications such as drug delivery. The portable simple analytical formula is a powerful asset to experimental researchers and design engineers in colloid science and technology to facilitate their works. 相似文献
992.
993.
研究蛋白质互作的化学生物学方法主要有荧光共振能量转移(Fluorescence resonance energy transfer, FRET)、酵母双杂交(Yeast two-hybrid technology, YTH)、免疫共沉淀(Co-immunoprecipitation, Co-IP)等。在此基础上,为了发展一种新的研究生物大分子互作,特别是膜蛋白相互作用的定量计算方法,依据前期研究发现,应用ELISA方法与QAH-NEU-1定量芯片技术检测NLRP2:ShRNAs慢病毒(Lentivirus)感染人脑微血管内皮细胞(Human brain microvascular endothelial cells, HBMEC), 敲除(Knocking down)NLRP2基因后的IL-18的分泌量与对照组比较, 显著提高(IL-18: 998 pg/mL),表明它在炎症免疫中起关键调控作用。本文采用高性能的Discovery Studio 2021(DS2018R2)大分子计算模拟软件,在RCSB PDB数据库中调用蛋白质文件建立其立体结构,应用ZDOCK程序算法探究IL-18亚基(AB亚基或B亚基)与IL-18R互作的空间结构与构象变化,计算找到了相互作用界面的氨基酸的一级序列与二级结构,以及它们之间的相互作用力,并用拉氏图评估对接构象,研究发现B亚基在IL-18与IL-18R的结合中起主要作用。该计算方法与实验方法比较,可快速找到蛋白-蛋白相互作用的构象空间,优化膜蛋白互作的精度;能从原子与量子水平探究细胞因子与膜蛋白受体的互作;更深入解析分子机理,数据精确定量。研究结果表明本文应用ZDOCK算法建立了通过计算模拟膜蛋白生物大分子互作的新领域,为细胞因子与化学因子的多肽类药物开发提供新的思路; 为细菌病毒感染/肿瘤疾病的防治提供科学理论依据; 在分子识别,神经元网络深度学习,生物信息处理领域具有广泛的应用。 相似文献
994.
Francesco Tavella Daniele Giusi Claudio Ampelli 《Current Opinion in Green and Sustainable Chemistry》2022
The direct electrocatalytic production of ammonia (NH3) from N2 and H2O at ambient conditions is one of today's chemical challenges to meet the growing industrial demand for ammonia. Despite numerous studies on designing novel catalysts to activate N2 molecule and elucidating the reaction mechanism, many critical factors (such as gas diffusion and charge transfer limitations that instead promote the side reaction of hydrogen evolution) remain unsolved, suggesting that a breakthrough is needed to improve performance in this challenging reaction. Based on this, we review here recent studies that propose advanced solutions, focusing on: (i) the adoption of a three-dimensional nanoarchitecture of the electrode surface (to favour multi-electron transfer), (ii) the design of cell configuration (including the development of gas diffusion electrodes – GDEs), (iii) the critical aspects of the more efficient lithium-mediated approach in non-aqueous solvents (flooding of the GDE, sustainability of the proton-shuttle system), (iv) new methods for ammonia detection avoiding false positive. 相似文献
995.
In this paper, the Gibbons and Werner technique is used to calculate the weak deflection angle for the black hole solution under the effects of Einstein–Gauss–Bonnet gravity. The Gauss–Bonnet theorem in the limits of weak field is used to evaluate the Gaussian optical curvature in order to obtain the results. The visual effects of the deflection angle on the impact parameter is also looked at and the smallest radius in the non-plasma/plasma medium. Moreover, in order to check the consistency of the results concerning the weak deflection angle, the Keeton and Petters approach is applied to study the deflection angle, which is the expansion of series with a single mass variable, which can be directly addressed by using the post–post Newtonian framework. Furthermore, the deflection angle and shadow under the influence of the plasma is examined by using the motion of particle in a non-magnetized plasma and pressure-free plasma medium as described by the new ray-tracing algorithm. It is shown that plasma as well as Einstein–Gauss-Bonnet gravity corrections are affected by shadows. 相似文献
996.
量子点太阳电池现已成为极具潜力的“第三代” 光伏器件, 其优点体现在材料成本低廉, 制备工艺简便, 以及其敏化剂特有的多激子效应(MEG) 潜能和吸光范围可方便调节等方面. 但是与染料分子敏化剂相比, 量子点敏化剂粒径更大、表面缺乏具有与TiO2结合的官能团, 这导致其在TiO2介孔中渗透阻力大、难以在TiO2表面吸附沉积, 所以量子点沉积手段在电池组装过程中尤为重要. 本文综述了电池组装过程中量子点的沉积方法, 分类阐述了直接生长量子点方法: 化学浴沉积(CBD)和连续离子层吸附生长(SILAR), 以及采用预先合成量子点的沉积方法: 连接分子辅助法(LA)、直接吸附法(DA)和电泳沉积(EPD)方法, 陈述了各沉积方法的发展过程及相应电池性能的改善, 对比了这些沉积方法的优缺点. 突出介绍了预先合成量子点的沉积方法, 特别是近年来不断优化而凸显优势的连接分子辅助法(LA). 总结了此方法快速、均匀沉积以及实现器件高性能的特点, 介绍了此方法沉积表面缺陷更少、结构更完善、材料更“绿色化”的量子点敏化剂的最新研究成果. 相似文献
997.
We use the Schwinger-boson approach to study the anisotropy ferrimagnetic spin-(1/2,1) chain with bond alternation.Based on the effect of bond alternation δ,we obtain energy gap,free energy,and specific heat,respectively.The specific heat with larger bond alternation(δ 0.7) displays a peak at low temperature.Based on the effect of XXZ anisotropy parameter δ,we present excited spectrums,free energy,and specific heat,respectively. 相似文献
998.
Empirical model potentials are found to be very useful for generating most competitive minima of large water clusters, whereas correlated (e.g. second order-Møller–Plesset perturbation (MP2) theory or higher) calculations are necessary for predicting their accurate energetics and vibrational features. The present study reports the structures and energetics of (H2O)32 clusters at MP2 level using aug-cc-pvDZ basis set, starting with low-lying structures generated from model potentials. Such high-end and accurate calculations are made feasible by the cost-effective fragment-based molecular tailoring approach (MTA) in conjunction with the grafting procedure. The latter is found to yield electronic energies with a sub-millihartree accuracy with reference to their full calculation counterparts. The vibrational spectra of nine low-lying (H2O)32 isomers are obtained from the corresponding MTA-based Hessian matrix. All these low-lying isomers show almost similar spectral features, which are in fair agreement with the experiment. The experimental spectrum of (H2O)32 is thus better understood from the vibrational features of this set of very closely spaced isomers. The present case study of (H2O)32 clearly demonstrates the efficacy in obtaining accurate structures, energetics and spectra at correlated level of theory by combining model potential-based structures with fragmentation methods. 相似文献
999.
Ilya E. Titkov Amit Yadav Sergey Yu. Karpov Alexei V. Sakharov Andrey F. Tsatsulnikov Thomas J. Slight Andrei Gorodetsky Edik U. Rafailov 《Laser \u0026amp; Photonics Reviews》2016,10(6):1031-1038
The future generation of modern illumination should not only be cheap and highly efficient, but also demonstrate high quality of light, light which allows better color differentiation and fidelity. Here we are presenting a novel approach to create a white solid‐state light source providing ultimate color rendition necessary for a number of applications. The proposed semi‐hybrid device combines a monolithic blue‐cyan light emitting diode (MBC LED) with a green‐red phosphor mixture. It has shown a superior color rendering index (CRI), 98.6, at correlated color temperature of around 3400 K. The MBC LED epi‐structure did not suffer from the efficiency reduction typical for monolithic multi‐color emitters and was implemented in the two most popular chip designs: “epi‐up” and “flip‐chip”. Redistribution of the blue and cyan band amplitudes in the white‐light emission spectrum, using the operating current, is found to be an effective tool for fine tuning the color characteristics.
1000.
The non-linear free and forced vibrations of simply supported thin circular cylindrical shells are investigated using Lagrange's equations and an improved transverse displacement expansion. The purpose of this approach was to provide engineers and designers with an easy method for determining the shell non-linear mode shapes, with their corresponding amplitude dependent non-linear frequencies. The Donnell non-linear shell theory has been used and the flexural deformations at large vibration amplitudes have been taken into account. The transverse displacement expansion has been made using two terms including both the driven and the axisymmetric modes, and satisfying the simply supported boundary conditions. The non-linear dynamic variational problem obtained by applying Lagrange's equations was then transformed into a static case by adopting the harmonic balance method. Minimisation of the energy functional with respect to the basic function contribution coefficients has led to a simple non-linear multi-modal equation, the solution of which gives in the case of a single mode assumption an expression for the non-linear frequencies which is much simpler than that derived from the non-linear partial differential equation obtained previously by several authors. Quantitative results based on the present approach have been computed and compared with experimental data. The good agreement found was very satisfactory, in comparison with previous old and recent theoretical approaches, based on sophisticated numerical methods, such as the finite element method (FEM), the method of normal forms (MNF), and analytical methods, such as the perturbation method. 相似文献