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91.
宋鹏 翟传磊 李双贵 勇珩 齐进 杭旭登 杨容 成娟 曾清红 胡晓燕 王帅 施意 郑无敌 古培俊 邹士阳 李欣 赵益清 张桦森 张爱清 安恒斌 李敬宏 裴文兵 朱少平 《强激光与粒子束》2015,27(3):032007-68
介绍了辐射流体力学程序LARED集成程序的物理背景、模型方程、数值方法和数值算例。该程序主要应用于激光间接驱动惯性约束聚变的二维整体模拟,兼顾激光直接驱动、辐射驱动靶丸内爆过程和流体不稳定性等物理过程的数值模拟。通过与实验数据、一维辐射流体力学程序进行比对,验证了程序的可靠性。该程序实现了多群输运建模下NIF点火靶的全过程数值模拟,并已应用于惯性约束聚变的物理研究。 相似文献
92.
The example of syn-aldol reaction of cyclohexanone to aldehyde was demonstrated based on chiral diamine organocatalysts and it was realized either by increasing the molecular size of acid additives or by introducing a hydrogen-bond donor into acid additives. 相似文献
93.
Yulin Jie Dr. Xiaojing Liu Zhanwu Lei Shiyang Wang Yawei Chen Fanyang Huang Prof. Ruiguo Cao Prof. Genqiang Zhang Dr. Shuhong Jiao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3533-3538
Lithium metal is an ideal electrode material for future rechargeable lithium metal batteries. However, the widespread deployment of metallic lithium anode is significantly hindered by its dendritic growth and low Coulombic efficiency, especially in ester solvents. Herein, by rationally manipulating the electrolyte solvation structure with a high donor number solvent, enhancement of the solubility of lithium nitrate in an ester-based electrolyte is successfully demonstrated, which enables high-voltage lithium metal batteries. Remarkably, the electrolyte with a high concentration of LiNO3 additive presents an excellent Coulombic efficiency up to 98.8 % during stable galvanostatic lithium plating/stripping cycles. A full-cell lithium metal battery with a lithium nickel manganese cobalt oxide cathode exhibits a stable cycling performance showing limited capacity decay. This approach provides an effective electrolyte manipulation strategy to develop high-voltage lithium metal batteries. 相似文献
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95.
The location of bifurcation points and bifurcation diagrams is important for the understanding of a nonlinear system with parametric resonance. This paper presents a model-less method to predict bifurcations of slightly damped multi-degree-of-freedom nonlinear systems with parametric resonance using transient recovery data in the pre-bifurcation regime. This method is based on the observation that the envelope amplitude of a decaying response in the pre-bifurcation regime recovers more slowly to the equilibrium as the system becomes closer to the bifurcation. Data obtained from both simulations and experiments are used to forecast the location of the bifurcation point and the bifurcation diagram. Forecasting results demonstrate that the method can be used to predict the bifurcation accurately under a set of specific assumptions. 相似文献
96.
脆性梁在纯弯曲断裂时会产生多个碎片, 其断裂过程直接影响弯曲波的产生和传播, 以及产生碎片的平均尺度. 采用内聚力断裂模型对脆性梁的弯曲断裂过程进行有限元数值模拟, 再现了断裂中的裂纹扩展过程, 分析了脆性梁断裂后断裂面弯矩与裂纹张开角之间的规律. 数值结果表明: (1)在一个广泛的材料参数和加载应变率条件下, 断裂面弯矩与裂纹张开角之间均呈相似的单调衰减规律; (2)断裂过程中弯矩做功与断裂面的表面能一致; (3)在纯弯矩作用下, 裂纹前端总是存在压应力区域, 使得断裂末期应力状态较为复杂, 断裂不再是纯弯曲状态. 相似文献
97.
利用溶胶-凝胶和溶剂热联合技术制备了Pr-N-P三元掺杂锐钛矿TiO2(PrNPTO)纳米片,并采用X射线衍射、透射电镜、N2吸附、X射线光电子能谱、UV-vis吸收谱和光致荧光光谱分析技术对其进行了表征.当Pr掺杂量为1.75wt%,焙烧温度为550℃时,制得的PrNPTO在可见和紫外光下光催化降解亚甲基蓝(MB)活性最佳.在模拟太阳光照射下,PrNPTO也表现出优越的光催化降解4-氯酚性能(kapp=3.90×10-2min-1),优于未掺杂、单掺杂和双掺杂TiO2样品,其光活性是P25TiO2的3.33倍(kapp=1.17×10-2min-1).PrNPTO光活性的提高归因于Pr-N-P三元掺杂增强了紫外和可见光吸收,降低了光生载流子复合,增加了表面羟基以及改善了表面织构特性.在模拟太阳光照射下,PrNPTO光催化效率高且光催化性能稳定,适合于环境净化领域的实际应用. 相似文献
98.
99.
Investigations of kinetics and mechanism of chloropinnoite in boric acid aqueous solution at 303 K by Raman spectroscopy 总被引:1,自引:0,他引:1
Xiaoping L Shiyang G Shuping X 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(12):2725-2728
Raman spectroscopy of dissolution and transformation of chloropinnoite in 4.5% (wt.%) boric acid aqueous solution at 303 K has been recorded. The Raman spectra of kinetics process have been obtained. The phase transformation product is 2MgO.3B2O3.15H2O (kurnakovite). The main polyborate anions and their interaction in aqueous solution have been proposed according to the Raman spectrum. Some assignments were tentatively given and the relations between the existing forms of polyborate anions and the crystallizing solid phases have been gained. A mechanism of dissolution and crystallization reactions and the formation condition of kurnakovite in Qinghai-Tibet plateau were proposed and discussed. 相似文献
100.