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91.
92.
M. D. Deshpande Ravindra Pandey Miguel A. Blanco Arun Khalkar 《Journal of nanoparticle research》2010,12(4):1129-1136
We report the magnetic properties of small Ni13-nAln\hbox{Ni}_{13-n}\hbox{Al}_n clusters with n = 0–13 calculated in the framework of density functional theory. The cluster magnetic moment decreases with the sequential
substitution of Ni by Al atoms, which can be attributed to a greater degree of hybridization that forces the pairing of the
electrons in the molecular orbitals of Ni and Al. For Ni7Al6, the complete quenching of the cluster magnetic moment appears to be due to the antiferromagnetic alignment of atomic spins
as revealed by the spin density plots. 相似文献
93.
The first step toward developing complete cell circuitry is to build quantitative networks for enzyme reactions. The conventional King-Altman-Hill (KAH) algorithm for topological analysis of enzyme networks, adapted from electrical networks, is based on “Reaction Graphs” that, unlike electrical circuits, are not quantitative, being straightforward renderings of conventional schematics of reaction mechanisms. Therefore, we propose the use of “Reaction Route (RR) Graphs” instead, as a more suitable graph-theoretical representation for topological analysis of enzyme reaction networks. The RR Graphs are drawn such that they are not only useful for visualizing the various reaction routes or pathways, but unlike Reaction Graphs possess network properties consistent with requisite kinetic, mass balance, and thermodynamic constraints. Therefore, they are better than the conventional Reaction Graphs for topological representation and analysis of enzyme reactions, both via the KAH methodology as well as via numerical matrix inversion. The difference between the two is highlighted based on the example of a single enzyme reaction network for the conversion of 7,8-dihydrofolate and NADPH into 5,6,7,8-tetrahydrofolate and NADP+, catalyzed by the enzyme dihydrofolate reductase. 相似文献
94.
Ashok Kumar Palakurthi Thirupathi Dongala Ravindra Kumar Yalavarthi Jayashree Anireddy 《Biomedical chromatography : BMC》2020,34(2):e4755
The main objective of this study was to establish an efficient extraction procedure for the estimation of telmisartan, amlodipine and chlorthalidone from their combination in sample matrix using an analytical quality by design approach. Initial screening studies were performed for optimization of a suitable diluent to extract active components from sample matrix. Further, the same study was extended for the identification of critical method attributes and the factors affecting the analytical target profile. This study also explains the rugged and robust quantitative determination of combinations drugs with a shorter run time. The design of experimental studies confirms that the current center point parameters are well suited to recoveries. The chromatographic separation was achieved with an X-Terra RP8, 150 × 4.6 mm, 3.5 μm column with an isocratic mobile phase (mixture of 20 mm aqueous ammonium acetate and acetonitrile). To demonstrate the stability-indicating nature of the optimized method, forced degradation studies were conducted and proved. The optimized method was validated according to International Conference on Harmonization guidelines. 相似文献
95.
Ravindra R. Shinde Dattatray Gaikwad Mazahar Farooqui 《Journal of heterocyclic chemistry》2020,57(11):3907-3917
A new series of 2-(4-(benzo[d]thiazol-5-ylsulfonyl)piperazin-1-yl)-N-substituted acetamide (5a-5k) compounds have been synthesized, and these compounds were characterized with spectral data like IR, NMR, and Mass spectroscopy. All compounds were evaluated in vitro for their efficacy as antimicrobial against Gram-positive and Gram-negative pathogenic bacterial strains such as Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa using ciprofloxacin as a standard and fungal strains like Candida albicans and Aspergillus fumigatus as compared with standard drug Clotrimazole, and Molecular docking study shows that all these compounds were having good to excellent correlation binding energy as compared with binding energy of standard drugs. 相似文献
96.
An inexpensive and safer reagent system comprising of PMHS and ZnCl2 has been developed for the selective reduction of carbonyl compounds to corresponding alcohols. 相似文献
97.
Synthesis and Spectral Characterization of Related Substances of Lacidipine,an Antihypertensive Drug
V. V. N. K. V. Prasada Raju Ganta Madhusudhan Reddy Vedantham Ravindra Vijayavitthal T. Mathad P. K. Dubey 《合成通讯》2013,43(12):2137-2145
Five related substances (impurities) were detected in lacidipine bulk drug substance by a simple high-performance liquid chromatographic method (HPLC) and were identified by liquid chromatography–mass spectrometry (LC-MS). These related substances were independently synthesized, characterized, and co-injected with the sample containing impurities. 相似文献
98.
Ravindra D. Jadhav Hitesh D. Mistry Hashim Motiwala Kishorkumar S. Kadam Shivaji Kandre Amol Gupte Ashok K. Gangopadhyay Rajiv Sharma 《Journal of heterocyclic chemistry》2013,50(4):774-780
Hydroxy (tosyloxy) iodobenzene (HTIB), a hypervalent iodine reagent, has been extensively used for oxidative transformations. We have developed a one‐pot synthesis wherein aldoximes when reacted with alkynes in the presence of HTIB result in the direct formation of isoxazoles. This simple and straightforward reaction allows for ease of purification while leading to the formation of high purity 3,5‐disubstituted isoxazoles in moderate yields. 相似文献
99.
Kumar Vijay Kushwaha Vikram Gandhi Yashika Mishra Sujeet K. Charde Vaibhav Jagtap Chandrashekhar Babu G. Singh Arjun Singh Ravindra Srikanth Narayanam 《平面色谱法杂志一现代薄层色谱法》2022,35(1):23-33
JPC – Journal of Planar Chromatography – Modern TLC - A new, simple, selective, sensitive, precise, and robust high-performance thin-layer chromatography (HPTLC) method for the... 相似文献
100.
Dr. Rajendran Manikandan Dr. Ravindra S. Phatake Prof. N. Gabriel Lemcoff 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(29):e202200634
The photochemical isomerization of α,β- to β,γ-unsaturated ketones through a 1,5-hydrogen atom transfer mechanism under mild conditions with high efficiency and selectivity is reported. The reaction is carried out in the absence of metal catalysts or other additives, and its stereoselectivity can be tuned by selecting appropriate solvent mixtures. The reaction‘s scope and tolerance towards functional groups, including light-sensitive halogens, free acids and alcohols, were studied, providing reliable access to a wide variety of β,γ-unsaturated ketones. This methodology details the deconjugation of a wide range of unsaturated ketones and, when combined with olefin metathesis, provides an efficient process for either dehomologation or one-carbon double-bond migration of terminal alkenes. 相似文献