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73.
T. V. V. Ramakrishna Anil J. Elias 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2513-2521
Dialkylamino substituted cyclic carbaphosphazenes, (R 2 NCN) 2 (NPCl 2 ) were prepared and reacted with the ferrocene derived hydroxymethyl phosphine sulfide FcCH(CH 3 )P(S)(CH 2 OH) 2 after dilithiation to yield a series of new spirocyclic derivatives of cyclic carbaphosphazenes having ferrocenyl pendant groups. To confirm the formation of six membered spirocycles and to compare their spectral features, transesterification reactions of FcCH(CH 3 )P(S)(CH 2 OH) 2 also were carried out with P(NR 2 ) 3 , yielding the six membered heterocycles FcCH 2 P(S)(CH 2 O) 2 PNR 2 (R = Me, Et). The compounds were characterized by 1 H, 31 P, 13 C NMR, mass spectra, and elemental analysis. 相似文献
74.
Ravindra Mahadev Patil Anil A. Ghanwat Satyanarayana Ganugapati 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):114-123
Well-defined four-arm star poly(?-caprolactone)-block-poly(cyclic carbonate methacrylate) (PCL-b-PCCMA) copolymers were synthesized by combining ring-opening polymerization (ROP) with atom transfer radical polymerization (ATRP). First, a four-arm poly(?-caprolactone) (PCL) macroinitiator [(PCL-Br)4] was prepared by the ROP of ?-CL catalyzed by stannous octoate at 110°C in the presence of pentaerythritol as the tetrafunctional initiator followed by esterification with 2-bromoisobutyryl bromide. The sequential ATRP of CCMA monomer was carried out by using the (PCL-Br)4 tetrafunctional macroinitiator (MI) and in the presence of CuBr/2, 2′-bipyridyl system in DMF at 80°C with [(MI)]:[CuBr]:[bipyridyl] = 1:1:3 to yield block polymers with controlled molecular weights (Mn (NMR) = 10700 to 27300 g/mol) by varying block lengths and with moderately narrow polydispersities (Mw/Mn = 1.2–1.4). Block copolymers with different PCL: PCCMA copolymer composition such as 50:50, 70:30 and 74:26 were prepared with good yields (48-74%). All these block copolymers were well characterized by NMR, FTIR and GPC and tested their thermal properties by DSC and TGA. 相似文献
75.
B.K. Sharma P. Singh M. Shekhawat K. Sarbhai Y.S. Prabhakar 《SAR and QSAR in environmental research》2013,24(3-4):365-383
76.
Reaction of TFA with sodium borohydride in THF is a loss of thermal control involving the evolution of Hydrogen gas. The investigation of the process by RC1e and ARSST showed that the criticality class of the reaction is dependant on the addition of TFA. Heat of reaction (Q r), adiabatic temperature rise (ΔT ad), and MTSR data are obtained from RC1e experiment. Exothermic onset temperature, Pressure rise, and self heat rate data are obtained from ARSST experiments. The correlation of these data was utilized to define the criticality class of the reaction under different conditions. The reaction with uncontrolled addition of TFA falls in the undesirable criticality class 5. Vent size data are obtained from the adiabatic calorimeter for undesirable reaction. The criticality class can be changed to class 2 with controlled addition. Accordingly, interlock system to control the undesired reaction and appropriate vent relief system are provided. 相似文献
77.
An efficient, facile preparation of aldehyde 1,1‐diacetates (acylals) in excellent yields catalyzed by RuCl3 · xH2O is described. Ketones do not react under these conditions. 相似文献
78.
Kalkote Uttam Ramrao Choudhary Anil Ramkumar Natu Arvind Anant Ayyangar Nagaraja Ramanuja 《合成通讯》2013,43(10-11):1129-1135
1-Alkylaminoanthraquinones ( 2 a-f) and 1,4-bisalkylaminoanthraquinones ( 4 a-c) were prepared from aminoanthraquinones ( 1,3 ) by alkylation with alkyl sulphate/alkyl halide in presence of powdered sodium hydroxide, potassium carbonate and phase transfer catalyst. 相似文献
79.
M. Anil Kumar K. R. Kishore Kumar Reddy M. Veeranarayana Reddy C. Devendranath Reddy 《合成通讯》2013,43(13):2089-2095
An efficient and direct approach for the α-thiocyanation of ketones with α-hydrogens has been developed using ammonium thiocyanate as a thiocyanating agent and oxone as an oxidant in methanol. 相似文献
80.
1‐[(Substituted carbamoyl)amino]‐1H,3H‐1λ5‐[1,3,2]oxazaphospholo[3,4‐a]benzimidazol‐1‐ones were synthesized by reacting benzimidazole 2‐methanol (4) with different chlorides of carbamidophosphoric acids (3) in the presence of triethylamine at 40–45°C. Their 1H, 13C, and 31P NMR spectral data were discussed. The title compounds were tested for their activity against the fungi Aspergillus niger and Fusarium solani and bacteria Staphylococcus aureus and Escherichia coli. These compounds showed moderate antibacterial activity when compared with antifungal activity. 相似文献