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41.
B. A. Ananchenko L. A. Kalinina Yu. N. Ushakova E. G. Fominykh E. V. Koshurnikova 《Russian Journal of Electrochemistry》2009,45(6):684-692
The CaYb2S4 compound and the phases based on it are fabricated. The ranges of solid solutions of CaS and Yb2S3 in calcium thioytterbiate are determined using the methods of x-ray diffraction analysis and conductometry. Average ionic, electronic, cationic, and anionic transport numbers and the coefficients of self-diffusion and diffusion of majority carrier in the Yb2S3 solid solution based on CaYb2S4 are determined by the modified emf method, the polarization Hebb-Wagner method, and potentiostatic chronoammetry. To discuss the mechanism of ionic transfer, the data on the pycnometric and X-ray densities are compared. 相似文献
42.
基于尖晶石晶体结构信息,本文采用热力学三亚晶格模型,将材料热力学计算和第一性原理计算相结合,研究了Zn_xMn_(1-x) Fe_2O_4和Ni_xMn_(1-x)Fe_2O_4立方相中的Zn~(2+)、Ni~(2+)、Mn~(2+)以及Fe~(3+)在8a和16d亚晶格上的占位有序化行为。结果表明:在锰铁氧体中,室温下Mn~(2+)完全占据在8a亚晶格上,Fe~(3+)完全占据在16d亚晶格上,属于正尖晶石结构;随着热处理温度升高,在1 273 K达到热处理平衡时的占位构型为(Fe~(3+)0.09Mn~(2+)0.91)[Fe~(3+)1.91Mn~(2+)0.09]O_4,在热处理温度升至1 473 K时,达到热处理平衡时的占位构型为(Fe~(3+)0.11Mn~(2+)0.89)[Fe~(3+)1.89Mn~(2+)0.11]O_4,均与实验结果符合较好。在锌铁氧体中,室温下Zn~(2+)完全占据在8a亚晶格上,Fe~(3+)完全占据在16d亚晶格上,属于正尖晶石结构;在热处理温度较高时,Zn~(2+)和Fe~(3+)发生部分置换,符合实验结果。在镍铁氧体中,半数的Fe~(3+)在室温下占据在8a亚晶格上,Ni~(2+)与剩下另一半的Fe~(3+)共同占据在16d亚晶格上,仅在热处理温度较高的时候发生微弱变化,亦与已有的实验结果吻合。在此基础上,本文进一步通过热力学模型研究了立方相尖晶石结构的Zn_xMn_(1-x)Fe_2O_4、Ni_xMn_(1-x)Fe_2O_4复合体系中阳离子占位行为与热处理温度对占位的影响规律。 相似文献
43.
采用傅里叶变换红外光谱(FTIR)及其二阶导数谱对不同生长年限当归药材进行分析研究.结果表明,不同生长年限当归药材的红外图谱较为相似,仅从一维谱图上无法反映出不同生长年限当归药材的红外特征谱明显的异同,但通过二阶导数图谱中1771、1747、1712、1559、1514、1466、766、711cm-1和668cm-1处的峰型差异可发现不同生长年限当归药材之间的一些成分存在较明显的差异.由于生长时间不同,导致它们的化学成分存在差异,所以体现了各自的红外特征谱,其中第三年当归药材与第一年和第二年当归药材间差异较大. 相似文献
44.
45.
1 INTRODUCTIONWith the invention of lasers[1] and the observation of second-harmonic generation in quartz[2], nonlinear optics(NLO), as a cornerstone of photonics, has been booming since 1960's. And intense interest has been aroused to search materials exhibiting appropriate nonlinear optical properties suitable for the construction of practical optical devices for the important techniques such as frequency converting, signal processing and optical computing[3~6]. In order to determine … 相似文献
46.
L. A. Novokshonova T. M. Ushakova M. V. Lysova O. I. Kudinova V. G. Krasheninnikov A. L. Lyubimtsev 《Macromolecular Symposia》2007,260(1):107-113
The supported metallocene catalysts were obtained on the layered silicate montmorillonite (MMT), using AlMe3 and AliBu3 for synthesis of alkylaluminoxane directly on a support surface, followed by metallocene supporting. It was shown that the MMT-H2O/AliBu3 forms with ansa-Zr-cenes of C1 and C2-symmetry the significantly more active supported metal-alkyl complexes in propene polymerization, than MMT-H2O/AlMe3. The MMT-H2O/AliBu3 is the effective activator of the ansa-Hf-cenes, in contrast to MAO and MMT-H2O/AlMe3, giving the high active supported catalysts for synthesis of isotactic and elastic polypropene. The character of influence of metallocene fixation on support on the isotactic pentad [mmmm] content in polymer, compared to homogeneous analogues, depends on the metallocene nature. The introduction of borate Ph3CB(C6F5)4 in the case of both Zr-cene and Hf-cene catalysts increases significantly the activity at the reduced ratio of Al/Zr, Hf (100–500 instead of 2000–3000) and stabilizes the catalytic complexes. 相似文献
47.
SABen-Hao CAIXu TAIAn ZHOUDai-Mei 《理论物理通讯》2004,42(3):403-406
We present the simulation results of the net charge fluctuation in Au Au collisions at √Snn=130 GeV from a dynamic model, JPCIAE, and its revisions. The simulations are done for the quark-gluon matter, the directly produced pions, the pion matter, and the hadron matter. The simulated net charge fluctuation of the quark-gluon matter is close to the thermal model prediction for the quark-gluon gas. However, the discrepancy exists comparing the simulated net charge fluctuation for directly produced pions and the pion matter with the thermal model prediction for pion gas and the resonance pion gas, respectively. The net charge fluctuation of hadron matter from default JPCIAE simulations is nearly 3.5 times larger than quark-gluon matter. A discussion is given for the net charge fluctuation as an evidence of QGP phase transition. 相似文献
48.
Pentin M. A. Ananchenko B. A. Kalinina L. A. Kosheleva E. V. Ushakova Yu. N. Murin I. V. 《Russian Journal of Electrochemistry》2019,55(8):785-795
Russian Journal of Electrochemistry - Abstract—Sulfide-conducting ionic salts: calcium thioyttrate and thioytterbate and barium thiosamarate with the citrate-nitrate prehistory and also a... 相似文献
49.
A. P. Ushakova 《Journal of Mathematical Sciences》1998,92(3):3949-3954
The problem of estimation of stability of reconstruction of the multiplicative exponential type is investigated. Some estimates
of the stability are derived.
Proceedings of the Seminar on Stability Problems for Stochastic Models, Hajdúszoboszló, Hungary, 1997, Part I. 相似文献
50.
E. G. Fominykh L. A. Kalinina Yu. N. Ushakova G. I. Shirokova T. I. Rychkova B. A. Ananchenko 《Russian Journal of Electrochemistry》2007,43(5):545-551
Nonstoichiometry of sulfides of cadmium and lead is studied by the method of coulometric titration in electrochemical cells with sulfide-conductive solid electrolytes on the basis of MLn2S4. The range of the homogeneity region is estimated at temperatures 300 to 400°C. A feasible model for the formation of defects in nonstoichiometric sulfides of cadmium and lead is proposed. 相似文献