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Wenhu Han Wenkai Liang Cheng Wang Jennifer X. Wen Chung K. Law 《Proceedings of the Combustion Institute》2021,38(3):3575-3583
This work studies numerically the spontaneous initiation and sustenance of a detonation wave from a hot spot with a nonuniform initial temperature embedded within an H2O2 mixture with and without O3 addition. For the case with either no or just a small amount of O3 addition, a weak reaction wave is auto-ignited at the hot spot, accelerates and then transitions to a pulsating detonation, which propagates along the temperature gradient and quenches as it runs into the cold fresh mixture. However, with increasing O3 addition, the possibility of sustenance of a developing detonation within the gradient is significantly enhanced as it enters the cold mixture. Furthermore, the reduced induction time by O3 addition leads to earlier appearance of the spontaneous reaction wave and detonation formation in the cold mixture, demonstrating that quenching of the detonation is largely related to the instability property of the mixture because the shortened induction time reduces substantially the instability. It is also noted that, for 5%O3 addition, a low-temperature flame produced by the O3 reactions is present in front of the spontaneous reaction wave, inducing a local pressure wave, which facilitates spontaneous initiation and sustains the detonation entering the cold mixture. Moreover, O3 addition renders the critical temperature to induce the minimum spontaneous wave speed higher than the crossover temperature, while they are very close for the case without O3. 相似文献
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卢洪洋 刘小雨 丁兵 刘忠 P.Doornenbal A.Obertelli S. M.Lenzi P. M.Walker L. X.Chung B. D.Linh G.Authelet H.Baba D.Calvet F.Chateau A.Corsi A.Delbart J. M.Gheller A.Gillibert T.Isobe V.Lapoux M.Matsushita S.Momiyama T.Motobayashi M.Niikura F.Nowacki H.Otsu C.Péron A.Peyaud E. C.Pollacco J. Y.Roussé H.Sakurai M.Sasano Y.Shiga S.Takeuchi R.Taniuchi T.Uesaka H.Wang K.Yoneda 《原子核物理评论》2020,37(3):548-553
利用放射性束68Fe轰击液氢靶引起的敲出反应,研究了极端丰中子核63,65,67Mn的激发态,指认了它们的自旋宇称,建立了这三个原子核的能级纲图。纲图包含11/2–、9/2–和 7/2– 三个激发态以及$5/2_{\rm{g.s.}}^{-}$ 基态,它们由三条$\Delta I \!=\! 1$ 的$\gamma$ 跃迁连接。这种能级结构与$K \!=\! 5/2$ 时强耦合转动带的特征一致。使用改进的LNPS有效相互作用(LNPSm)的大规模壳模型计算能很好地重现观测到的能级。计算表明,65,67Mn的低位激发态都主要包含处于$4p{\text -}4h$ 的中子组态和$1p{\text -}1h$ 的质子组态。基于实验结果发现,在吸积中子星壳中,与质量数$A \!=\! 63$ 相关的Urca中微子冷却效果比预期的要强很多,而$A \!=\! 65, 67$ 的冷却效果比预期的更弱。 相似文献
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The N-terminal fragment of prohormone brain natriuretic peptide (NT-proBNP) is a commonly used biomarker for the diagnosis of congestive heart failure, although its biological function is not well known. NT-proBNP exhibits heavy O-linked glycosylation, and it is quite difficult to develop an antibody that exhibits glycosylation-independent binding. We developed an antibody that binds to the recombinant NT-proBNP protein and its deglycosylated form with similar affinities in an enzyme immunoassay. The epitope was defined as Gly63–Lys68 based on mimetic peptide screening, site-directed mutagenesis and a competition assay with a peptide mimotope. The nearest O-glycosylation residues are Thr58 and Thr71; therefore, four amino acid residues intervene between the epitope and those residues in both directions. In conclusion, we report that an antibody reactive to Gly63–Lys68 of NT-proBNP exhibits O-glycosylation-independent binding. 相似文献
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Hari M. Srivastava Kun‐Jen Chung Jui‐Jung Liao Shy‐Der Lin Sheng‐Tu Chuang 《Mathematical Methods in the Applied Sciences》2019,42(11):3967-3977
Several recent studies in supply chain system and related areas explored various economic order quantity (EOQ) models for noninstantaneous deteriorating items with imperfect quality and trade credit financing. In particular, in the year 2007, Teng et al investigated an EOQ model in which the supplier offers the retailer the permissible delay period M and the retailer, in turn, provides the trade credit period N (with ) to his/her customers. The main purpose of this article is twofold: (a) It modifies the annual total relevant cost TVC(T) in the study of Teng et al and presents the correct derivations of TVC(T) by applying mathematical analytic tools and techniques. (b) It exposes some logical and mathematical problems in the proof of Theorem 1 in Teng et al. It also corrects and overcomes all of the errors and shortcomings by systematically presenting the complete and mathematical solution procedures in order to locate all optimal solutions for the model in Teng et al. 相似文献
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By taking into account effects of tunneling on the shape of the falloff curves of unimolecular reaction rate constants based on Troe's weak collision integral, a fitting formula for these curves is developed and then examined for several tunneling‐affected reactions. It is demonstrated that, compared to the widely used Troe's formula, the present expression not only substantially enhances the accuracy in fitting for tunneling‐affected reactions, but it is also computationally more efficient in its evaluation. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 43: 31–42, 2011 相似文献