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1.
2.
All-channel time-dependent quantum mechanical reaction probabilities are reported for the collinear He + H+2(ν = 0, 1, 2) → HeH+ + H reaction at a total energy of 1.2 eV on previously reported diatomics-in-molecule (DIM) and spline fitted ab initio (SAI) surfaces. These results are in agreement with the previous quasiclassical trajectory results in that there is vibrational enhancement of the reaction probability on the SAI surface but not on the DIM surface. This agreement lends support to our previously drawn conclusion that small differences in the potential-energy surface can lead to substantially different dynamic results. 相似文献
3.
S.K. Rangarajan 《Journal of Electroanalytical Chemistry》1975,62(1):31-41
A functional expression is derived valid for evaluating all orders of perturbation in potential when a current of known profile is super-imposed. Generalised expressions for the distortion and the rectification potential are given. The problems of “iR-drop” and “charging current” compensation are also discussed. 相似文献
4.
P. Govindan A. Palamalai K. S. Vijayan K. Dhamodharan S. Subbuthai S. V. Mohan R. V. Subba Rao 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(3):571-574
A method is developed for the selective leaching of 233U from a thorium oxalate cake. The leaching capacity of ammonium carbonate and nitric acid have been investigated, showing that (NH4)2CO3 leads to higher recovery. The maximum leaching efficiency is obtained using 0.5% ammonium carbonate, with a minimal thorium pick-up. A uranium recovery of 94% is obtained after three consecutive contact experiments in carbonate media, with minimal thorium uptake in the leachate. This process was applied to an actual plant stream, allowing the reduction of the 233U -activity from 5.64 to 0.3 Ci/g of thorium oxalate cake. 相似文献
5.
1-Amino-3-methoxypropane (3MPA) and 2-dimethylaminoethanol (DMAE) are potential volatile amines for boiler water treatment and were investigated for their complexation behaviour with copper. Their pKb values were 3.67 and 4.52 at 25°C and they formed coloured complexes with absorption in the region of 644 and 510 nm, respectively. In the pH range 10–11, the Cu-3MPA complex exhibited stepwise reduction and [Cu(3MPA)2]+ was identified, with a stability constant of 109.52. In the pH range 8–10.5, the Cu-DMAE complex exhibited 2e? reduction and the species [Cu(DMAE)2(OH)2] was identified, with a stability constant of 1020.39. A correlation between visible and ESR spectra and reduction behaviour was established. 相似文献
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7.
M. Gopalakrishnan P. Sureshkumar V. Kanagarajan J. Thanusu Shanmugam Govindan Mahesh Reddy Ghanta 《合成通讯》2013,43(13):1923-1926
The p‐toluenesulphonic acid–catalyzed reaction between appropriate cresols and N‐methyl‐3‐phenyl‐3‐hydroxypropylamine in refluxing toluene resulted in the formation of o‐substituted phenol derivatives by an aromatic nucleophilic substitution reaction. 相似文献
8.
Drop calorimetric measurements on a versatile monazite phase loaded with simulated radioactive waste
R. Asuvathraman Kitheri Joseph Jose Joseph M. V. Krishnaiah K. V. Govindan Kutty 《Journal of Thermal Analysis and Calorimetry》2014,117(3):1151-1156
Monazite is one of the candidate ceramic matrices for the immobilization of high level radioactive waste (HLW) from the reprocessing of spent nuclear fuel. The monazite phase, Ce0.8Ca0.2PO4, can accommodate cations of different valences due to the mixed valence state (+3 and +4) of Ce in this compound, by facilitating the oxidation and reduction of the Ce3+ and Ce4+ as required by the in-coming cation. This will assist in accommodating HLW of different compositions in the monazite crystal structure even if the average valence of the HLW elements is other than 3. Therefore, the monazite phase, Ce0.8Ca0.2PO4, can be a versatile host for the immobilization of HLW. The enthalpy increment and heat capacity of this versatile monazite phase and a simulated waste form based on it with 20 mass% HLW oxides were measured by drop calorimetry in the temperature range from 373 to 873 K, and the results are compared with those measured for CePO4. 相似文献
9.
An efficient Pd‐catalyzed method for C—O cross‐coupling of ketoximes and chalcone oximes with activated aryl bromides and bromo‐chalcones has been developed. All oxime ethers were obtained in good to excellent yields by [(π‐allyl)PdCl]2/tBuXPhos ( L7 ) catalyst system. TrixiePhos ( L11 ) was also found to be effective for the oxime coupling. This method offers an easy and smooth coupling of chalcone oximes with activated aryl bromides and bromo‐chalcones, which has not been previously explored. 相似文献
10.
Ramajayam Govindan Mohamed El-Sherbiny Khalid Mohamed Morsy Ibraheem Srinivasan Narasimhan Mohamed EL-Dosoky Mohamed Salama Fazil Ahmad Selvaraj Jayaraman Vishnu Priya Veeraraghavan Srinivasan Vengadassalapathy Surapaneni Krishna Mohan Vidhya Rekha Umapathy Gayathri Rengasamy Shazia Fathima Jaffer Hussain Maheshkumar Poomarimuthu Senthilkumar Kalimuthu 《Molecules (Basel, Switzerland)》2022,27(3)