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排序方式: 共有380条查询结果,搜索用时 62 毫秒
121.
Ahmed Alsaedi Bashir Ahmad Mokhtar Kirane Belgacem Rebiai 《Mathematical Methods in the Applied Sciences》2019,42(12):4378-4393
Local and blowing‐up solutions for the Cauchy problem for a system of space and time fractional evolution equations with time‐nonlocal nonlinearities of exponential growth are considered. The existence and uniqueness of the local mild solution is assured by the Banach fixed point principle. Then, we establish a blow‐up result by Pokhozhaev capacity method. Finally, under some suitable conditions, an estimate of the life span of blowing‐up solutions is established. 相似文献
122.
Yong Zhou Jia Wei He Bashir Ahmad Nguyen Huy Tuan 《Mathematical Methods in the Applied Sciences》2019,42(18):6775-6790
In this paper, we study a backward problem for an inhomogeneous fractional diffusion equation in a bounded domain. By applying the properties of Mittag‐Leffler functions and the method of eigenvalue expansion, we establish some results about the existence, uniqueness, and regularity of the mild solutions as well as the classical solutions of the proposed problem in a weighted Hölder continuous function space. 相似文献
123.
124.
Hayat M. Marafie Mohammed S. El-Ezaby Bashir A. Abd-El-Nabey Nabil Kittaneh 《Transition Metal Chemistry》1982,7(4):227-233
Summary The stability constants of ternary CoII, NiII, CuII, ZnII and CdII complexes containing pyridoxamine as a first and ethylenediamine as a second ligand were determined by pH titration at I =0.50M NaNO3 and 30 °C. Most of the complexes are protonated, probably on the pyridoxamine moiety. The formation of the ternary complex species is discussed in terms of binary species formation. Spectral characteristics of some of the ternary complex systems are discussed.Part X. Binary, Ternary and Quaternary Complexes Involved in Systems of Pyridoxamine-Glycine or Glycylglycine-Imidazole with Some Bivalent Metal Ions,21st Internat. Conf. on Coord. Chem., Toulouse, France (1980); 相似文献
125.
Hallmann L Bashir A Strunskus T Adelung R Staemmler V Wöll Ch Tuczek F 《Langmuir : the ACS journal of surfaces and colloids》2008,24(11):5726-5733
The formation of self-assembled monolayers of benzylmercaptan (BM) and p-cyanobenzylmercaptan (pCBM) on Au(111) surfaces is investigated by a combination of X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS), and scanning tunneling microscopy (STM). The NEXAFS results of pCBM are supported by ab initio calculations. It is found that BM as well as pCBM form well-ordered monolayers with the molecules oriented almost perpendicular to the surface. BM forms a ( radical 3 x radical 3)R30 degrees structure whereas pCBM forms a slightly different c(7 x 7) hexagonal structure. No phase separation is detected for the adsorption of a 1:1 mixture of the two molecules. The implications of the results for the covalent attachment of transition-metal complexes to thiol-functionalized surfaces are discussed. 相似文献
126.
Amber Khuram Pervez Akram Waseem Bashir Muhammad Anser Khan Muhammad Sajid Kousar Anila 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2355-2366
Journal of Thermal Analysis and Calorimetry - At higher ambient temperatures during summer months, the cell temperature of a photovoltaic (PV) module increases to 50–60 °C and sometimes... 相似文献
127.
Hira Aslam Shazia Shukrullah Muhammad Yasin Naz Hareem Fatima Sami Ullah Abdullah G. Al-Sehemi 《Particle & Particle Systems Characterization》2021,38(12):2100179
Magnetically guided drug transportation is a technique in which magnetic pharmaceutical transporters in organisms are controlled by applied magnetic forces to deliver drugs to the desired location. Different magnetic drug delivery systems (MDDSs) are developed to treat a variety of illnesses, particularly cancer and neurological disorders. However, a unique magnetic setup is required in each application for an effective magnetically guided drug aiming to direct the drug-carrying nanocarriers to the intended area. The current and future perspectives of MDDS are investigated in this study by considering their biological functions, deliverable efficiency, complexity, and the nature of the externally applied magnetic field. Despite the fact that MDDSs have low cytotoxicity, regulated magneto reactivity, extended circulation lifespan, and high surface stability, very few clinical studies have been conducted to date in order to achieve optimized therapeutic efficacy before entering the market. In recent studies, the development of novel magnetic medication transporting carriers is preferred over direct magnetic medication administration. Better functional magnetic targeting technologies are required for such breakthroughs to enter clinical trials. Because MDDSs are unlikely to work in all clinical situations, more focused research is needed to replace or improve the strategy for treating multiple illnesses. 相似文献
128.
Muhammad U. Farooq Muhammad Y. Naz Muhammad I. Hussain Shazia Shukrullah Mohamed M. Makhlouf 《Particle & Particle Systems Characterization》2021,38(7):2100073
As several multi-target drug delivery approaches are successfully identified through preclinical screening, their clinical success is often hampered by challenges such as poor circulation stability, dissimilarities in the pharmacokinetics of different drugs, as well as targeting inefficiency. Gold nanoparticles (AuNPs) are adopted as promising nanocarriers in the co-delivery of multiple therapeutic drugs for combination therapy. The pH-responsive AuNPs are synthesized and incorporated with multiple chemotherapeutic drugs, such as doxorubicin and bleomycin. Such structures can work as drug carriers to treat cervical carcinoma by adopting a quality by design approach. The designed nanocarrier is characterized by adopting a range of physicochemical and morphological techniques. In vitro drug release and cytotoxicity of optimized nanocarriers are assessed to cervical tumor epithelial cells. The results highlight the notable advantages of colloidal AuNPs, including sustained drug release, therapeutic agent delivery with high stability, and biocompatibility for more effective treatment of cervical carcinoma. Furthermore, by improving the biodistribution and/or bioavailability profiles, it is believed that the two-in-one approach may therefore give evidence on the fate of co-loaded nanocarrier as a promising trajectory for successful clinical translation against ovarian carcinoma to achieve maximum therapeutic synergy for an individual patient. 相似文献
129.
Ahmed Alsaedi Bashir Ahmad Mokhtar Kirane Maryem Al‐Yami 《Mathematical Methods in the Applied Sciences》2017,40(4):1280-1287
Sufficient conditions are obtained for the nonexistence of solutions to the nonlinear higher order pseudo‐parabolic equation where is the Kohn‐Laplace operator on the (2N + 1)‐dimensional Heisenberg group , m≥1,p > 1. Then, this result is extended to the case of a 2 × 2‐system of the same type. Our technique of proof is based on judicious choices of the test functions in the weak formulation of the sought solutions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
130.
A single-crystal CaF2 (111) was irradiated with single and multiple laser (Ti:sapphire, 800 nm, 25 fs) shots at fluences ranging from 0.25 to 1.5 J cm?2. In this fluence regime, a single laser pulse usually leads to typical bump-like features ranging from 200 nm to 1.5 μm in diameter and 10–50 nm in height. These bumps are related to compressive stresses due to a pressure build-up induced by fast laser heating and their subsequent relaxation. When CaF2 is irradiated with successive (in our case 20) shots at a laser fluence of 1.5 J cm?2, nanocavities at the top of the microbumps are observed. The formation of these nanocavities is regarded as an explosion and is attributed to the explosive expansion generated by shock waves due to laser-induced plasma after the nonlinear absorption of the laser energy by the material. Such kinds of surface structures at the nanometre scale could be attractive for nanolithography. 相似文献