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101.
Device calibration impacts security of quantum key distribution 总被引:1,自引:0,他引:1
Jain N Wittmann C Lydersen L Wiechers C Elser D Marquardt C Makarov V Leuchs G 《Physical review letters》2011,107(11):110501
Characterizing the physical channel and calibrating the cryptosystem hardware are prerequisites for establishing a quantum channel for quantum key distribution (QKD). Moreover, an inappropriately implemented calibration routine can open a fatal security loophole. We propose and experimentally demonstrate a method to induce a large temporal detector efficiency mismatch in a commercial QKD system by deceiving a channel length calibration routine. We then devise an optimal and realistic strategy using faked states to break the security of the cryptosystem. A fix for this loophole is also suggested. 相似文献
102.
Manisha Sharma Arti Maheshwari Nitin Bindal 《Journal of heterocyclic chemistry》2013,50(Z1):E116-E120
Some new derivatives of 3‐chloro‐1‐(4a,10b‐diazaphenanthrene‐2‐yl)‐4‐phenyl azetidin‐2‐one were synthesized through the reaction of N‐{4‐[phenyldiazenyl] phenyl}‐N‐[phenyl methylene] amine with 4‐[phenyldiazenyl] aniline. The resulting 3‐chloro‐4‐phenyl‐1‐{4‐[phenyldiazenyl] phenyl} azetidin‐2‐one intermediate in benzene was irradiated in a Pyrex vessel with 350 nm UV light in a photochemical reactor to give the desired derivatives (4a–j) . Structures of the new compounds were verified on the basis of spectral and elemental methods of analyses. Nine of the prepared compounds were tested for their anti‐inflammatory effects; most of these compounds showed potent and significant results compared with indomethacin. 相似文献
103.
Nitin D. Gaikwad Sachin V. Patil Vivek D. Bobade 《Journal of heterocyclic chemistry》2013,50(3):519-527
A series of new 1‐[4‐(2,3,4‐substituted‐phenyl) thiazol‐2‐yl]‐3‐(2,3,4‐substituted‐phenyl)‐1H‐pyrazole‐4‐carbaldehyde ( 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i , 4j , 4k , 4l , 4m ), 4‐[4‐(4‐substituted‐phenyl) thiazol‐2‐yl]‐3‐(4‐substituted‐phenyl)‐1‐phenyl‐1H‐pyrazole ( 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i ), 4‐[4‐(4‐substituted phenyl)thiazol‐2‐yl]‐1‐phenyl‐1H‐pyrazol‐3‐amine ( 10a , 10b , 10c , 10d , 10e , 10f , 10g ) have been synthesized by using Vilsmeier Haack formylation and Hantzsch reaction in high yield. All the synthesized compounds were tested qualitative (Zone of inhibition) and quantitative antimicrobial activities (MIC). Most of the synthesized compounds showed potent antimicrobial activity against gram positive and gram negative bacteria as well as fungi species. 相似文献
104.
A simple, efficient, and green protocol for synthesis of coumarin-3-carboxylic acids is described via Knoevenagel condensation of Meldrum's acid with ortho-hydroxyaryl aldehydes in [Hmim]Tfa ionic liquid, which was found to give better results than other ionic liquids. Furthermore, ionic liquid is easily reused without any appreciable loss in activity. 相似文献
105.
Nitin R. Patel 《The Journal of the Operational Research Society》1980,31(8):733-741
This paper develops a computational algorithm for estimating the mean objective function value of a stochastic linear programming problem of the passive or wait-and-see type. The algorithm is applied to a problem connected with design of a milk-grid in India and is found to be computationally effective in that case. It is most likely to be useful in the case of fairly large LP problems with a few (<10) stochastic right hand side variables. 相似文献
106.
Inside Cover: A One‐Pot Chemically Cleavable Bis‐Linker Tether Strategy for the Synthesis of Heterodimeric Peptides (Angew. Chem. Int. Ed. 47/2016) 下载免费PDF全文
107.
Tapan Kumar Lai Asima Chatterjee Julie Banerji Deboleena Sarkar Nitin Chattopadhyay 《Helvetica chimica acta》2008,91(10):1975-1983
A microwave‐induced rapid and facile synthesis of the DNA‐intercalating and antimalarial drug cryptolepine is described. The key step in this synthesis involves the aqueous‐phase base‐catalyzed condensation of isatin and 1‐acetyl‐1H‐indol‐3‐yl acetate which has been simplified and expedited by dielectric heating, employing an ordinary domestic microwave oven. The method transforms the synthesis of an important drug molecule from a prohibitively lengthy process to a matter of a few minutes with a much improved yield. Dual absorption and fluorescence is observed from the molecular system in solvents of different polarity thus providing valuable insight into its binding modes toward protein or DNA. 相似文献
108.
The cyclization of amino-alkynes 1 in which an amino group is attached to the aromatic ring, proceeded smoothly using a catalytic amount of Pd(PPh3)4 and benzoic acid in toluene at 120 degrees C, leading to the formation of the 2-substituted tetrahydroquinolines 2. An asymmetric variant of the reaction using the chiral palladium catalyst (prepared in situ by mixing Pd2(dba)3.CHCl3 and (R,R)-RENORPHOS) was also explored. The absolute configuration of the enantiomerically enriched tetrahydroquinolines, obtained in this way, was determined by converting them to the known compounds and was found to be R. The alkaloids such as (+/-)-galipinine, (+/-)-angustureine, and their optically active form were synthesized by using this reaction as a key step. 相似文献
109.
Muchate Niramaya S. Kadam Nitin S. Rajurkar Nilima S. Nikam Tukaram D. 《平面色谱法杂志一现代薄层色谱法》2017,30(3):193-198
JPC – Journal of Planar Chromatography – Modern TLC - 20-Hydroxyecdysone (20E), an imperative phytoecdysteroid, regulates several biochemical and physiological processes during the... 相似文献
110.