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61.
合成了单元化学式为-Cu[(CH_3O)_2PO_2]_2-的铜(Ⅱ)与磷酸二甲酯的配位聚合物。测定了4000—100 cm~(-1)谱区内的红外光谱, 讨论了某些谱带的归属, 解释了配位化合物形成后的光谱变化。由单晶X-射线衍射法确定此配合物的晶体属单斜晶系,空间群为P2_1/c, 晶胞参数a=1.0704(4), b=0.5093(2), c=1.9737(6) nm; β=96.23(3)°; V=1.0696(6) nm~3; Z=4. M=313.5, F(000)=636e, D_c=1.943 g·cm~(-3)。铜与五个配体中的五个非酯氧配位成四角锥体, 相邻两铜原子以对称的“O—P—O”桥和不对你的“O—P—O”桥相连, 形成一维链状配位聚合物。 相似文献
62.
Dr. Abdus Samad Dr. Aamir Shafique Prof. Udo Schwingenschlögl Dr. ZongWei Ji Prof. Guangfu Luo 《Chemphyschem》2022,23(10):e202200041
Monolayer, bilayer, and bulk BSi are studied to explore their application potential as anode materials of Li-ion batteries. Structural stability and metallicity are obtained in each case. The Li storage capacities of monolayer and bilayer BSi are 1378 and 689 mAh g−1, respectively, with average open circuit voltages of 1.30 and 0.47 V as well as Li diffusion barriers of 0.48 and 0.27 eV. Bulk BSi realizes a layered structure in the presence of a small amount of Li and its Li diffusion barrier of 0.48 eV is identical to that of graphite and lower than that of bulk Si (0.58 eV). The Li storage capacity of bulk BSi is found to be 689 mAh g−1, i. e., much higher than that of graphite (372 mAh g−1). The volume expansion turns out to be 33 % and the chemical bonds remain intact at full lithiation, outperforming the 72 % volume expansion of bulk Si at the same capacity and thus pointing to excellent cyclability. 相似文献
63.
64.
优化了碱性阴离子交换膜燃料电池(AAEMFC)使用的气体扩散电极(GDE),发现催化层中PTFE含量与催化剂担载量对电池性能与其电化学动力学特征影响很大.采用i-V曲线,开路电压,电池内阻与在线的电化学阻抗谱与动力学分析,评估了所制GDE的电化学性能.在所研究的AAEMFC电极催化层中,PTFE的最佳含量是20%,Pt载量对膜电极三相界面、催化层导电性与催化剂利用率的影响极大.当制备的GDE催化层中Pt/C的Pt载量为1.0mg/cm2,PTFE含量为20%时,AAEMFC的峰电流密度在50oC达到了213mW/cm2.兼顾Pt催化剂的利用率与成本,在没有明显影响电池性能的情况下,Pt的担载量可降至0.5mg/cm2. 相似文献
65.
ONCONNECTIVITYOFTHEESSENTIALSPECTRAOFTOEPLITZOPERAtORSWITHSYMBOLSINH∞+C¥CAOGUANGFU;SUNSHANLI(DepartmentofMathematics,JinnUniv... 相似文献
66.
Chen Xiaoman Cao Guangfu Guo Kunyu 《Journal of Mathematical Analysis and Applications》2000,250(2):1666
The present paper shows that the algebra
generated by {C| Aut(Bn)} is cyclic on H2(Bn), and any nonconstant function f H2(Bn) is a cyclic vector of
. In addition, the hypercyclic and cyclic composition operators will be discussed. 相似文献
67.
ALS抑制剂合理分子设计的研究进展 总被引:6,自引:0,他引:6
以乙酰乳酸合成酶为靶标合理设计开发新型超高效除草剂是当前除草剂化学研究中的重要领域。结合本课题组的研究工作,从ALS抑制剂的结构特征、分子力学与量子化学研究、定量构效关系(QSAR)与三维定量构效关系(3D-QSAR)研究、非线性QSAR研究以及新型除草剂的分子设计等几个方面对该领域的研究现状进行了总结报道,并对该领域的发展前景及存在的问题进行了展望。 相似文献
68.
Pingyuan Wang Meining Wang Xuefeng Zhang Guangfu Yang Ao Zhang 《Tetrahedron》2012,68(27-28):5386-5390
Glycals have served as excellent substrates in the glycosidation reactions with arylamines to construct both C–C and C–N linkages simultaneously. However, the high reactivity and moisture/alcohol-sensitivity is also responsible for several side reactions. Herein we reported that 2,3-unsaturated glycosides can be used as alternatives of glycals to take part in the corresponding glycosidation as well. Therefore, with 10% of InBr3 or InI3 as the catalyst, 2,3-unsaturated glycosides containing various C-1 alkoxy groups reacted with arylamines smoothly and produced the glycosidation products in moderate to good yields as a pair of diastereomers with variant diastereoselectivity. 相似文献
69.
Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is one of the most significant targets for a large family of in- hibitors that may be used as herbicide, bactericide, fungicide, or photosensitizing activator to treat cancer through photodynamic therapy (PDT). Molecular docking and CoMFA were combined in a multistep framework with the ultimate goal of identifying important factor contributing to the activity of PPO inhibitors. As a continuation of the previous research work on the development of new PPO inhibitors, the bioassay results indicated that good PPO in- hibitors were discovered in all of the three chemical series with ICs0 values ranging from 0.010 to 0.061 pmol·L ^-1. Using the crystal structure of tobacco mitochondrial PPO (mtPPO) as template, all the compounds were docked into the enzyme active site. The docking pose of each compound was subsequently used in a receptor-based alignment, leading to the development of a significant CoMFA model with r^2 value of 0.98 and q^2 (cross validation r^2) value of 0.63. This novel multistep framework gives insight into the and it can be extended to other classes of PPO inhibitors. In be particularly applicable in virtual screening procedures. structural characteristics for the binding of inhibitors, addition, the simplicity of the proposed approach may 相似文献
70.
设X是齐型空间.设Tj,1和Tj,2是具有非光滑核的奇异积分箅子,或者是±I(I是恒等算子).令Toeplitz型算子Tb=N∑j=1Tj,1MbTj,2,其中Mbf(x)=6(x)f(x).研究了当b∈BMO(X)时,Tb(f)在加权情况下的有界性,以及当b∈BMO(X)时,与经典Carderón-Zygmund算子相联的Tb(f)在Morrey空间上的有界性. 相似文献