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101.
102.
金属锂具有最高的理论比容量(3860 mAh·g?1)和最低的还原电势(?3.04 V),是新型高能量密度电池负极材料的最佳选择之一。然而由于金属锂负极表面自发生成的固态电解质界面(SEI)十分不稳定,导致锂枝晶的产生和电池容量快速衰减,严重限制了锂金属电池的商业化应用。因此,本工作利用碳酸双(2,2,2-三氟乙基)酯(DTFEC)添加剂在三维锡锂合金/碳纸负极(SnLi/Cp)表面原位构筑了高机械强度和离子穿透性的含氟化物(LiF和SnF2)保护层,有效地改善了锂负极的倍率性能和循环稳定性。结果显示,SnLi/Cp对称电池在8 mA·cm?2的电流密度下经过100次循环后过电位仅为90 mV。当将电解液降低到12μL(1.5μL·(mAh)?1)时,在5 mA·cm?2的电流密度下对称电池仍具有优异的稳定性;SnLi/Cp||NMC811电池在1C(1.5 mA·cm?2)条件下能稳定循环300圈以上,库伦效率高达98.1%。这种方法能够显著改善锂金属负极的循环稳定性,有助于实现高能量密度锂金属电池的实际应用。 相似文献
103.
深空网测控模式△DOR测量建模与精度分析 总被引:2,自引:0,他引:2
差分干涉测量技术是获取深空探测器高精度角位置信息的重要技术手段. 本文以中国深空网在嫦娥3 号(CE'3 号) 任务中首次应用为背景,论述深空网测控模式差分干涉测量技术的测量模型,相对于传统的短时交替观测模式,该方法能够全时段确保目标航天器的遥测、遥控通信,克服短时交替引起的航天器遥测信息中断以及应急遥控指令无法发送的问题. 基于CE'3 号环月轨道段的实测数据处理结果,通过与事后精密轨道的精度比对表明,测量数据时延精度在1 ns 量级,相应于角位置精度97 nrad(地月距离上CE'3 号位置精度37 m),与具有相似基线构型的采用短时交替模式的CVN 网测量精度在同等量级. 相似文献
104.
ITER极向场馈线系统采用冷屏以降低4K温区低温部件的热负荷。该文对极向场馈线冷屏的初步设计进行介绍,并计算了冷屏的热负荷。 相似文献
105.
106.
A Green function formalism is employed to investigate the effect of magnetocrystalline anisotropy on surface spin waves in semi-infinite Heisenberg ferromagnets at low temperatures T << Tc. The dispersion relations are investigated in detail. The density of states (DOS) of surface spin waves and layered magnetizations are also derived. 相似文献
107.
108.
Rui GUO Jialin ZHANG Songtao ZHAO Xiaojiang YU Shu ZHONG Shuo SUN Zhenyu LI Wei CHEN 《物理化学学报》2017,33(3):627-632
Corannulene (COR) is considered a promising molecular building block for organic electronics owing to its intriguing geometrical and electronic properties. Intensive research efforts have been devoted to understanding the assembly behavior and electronic structure of COR and its derivatives on various metal surfaces via low-temperature scanning tunneling microscopy (LT-STM). Here we report the formation of binary molecular networks of copper hexadecafluorophthalocyanine (F16CuPc)-COR self-assembled on the highly oriented pyrolytic graphite (HOPG) and Ag (111) substrates. Intermolecular hydrogen bonding between F16CuPc and COR facilitates the formation of binary molecular networks on HOPG and further induces a preference for bowl-down configured COR molecules. This observed configuration preference disappears on Ag (111) substrate, where COR molecules lie on the substrate with their bowl openings pointing up and down randomly. We propose that strong interfacial interactions between the molecule and Ag (111) surface constrain the bowl inversion of the COR molecule, which thus retains its initial configuration upon adsorption. 相似文献
109.
Mi Zhou Songtao Cai Jie Li Xin Qian Haha Zheng 《Journal of inclusion phenomena and macrocyclic chemistry》2017,87(1-2):45-51
A novel hybrid magnetic nanoparticle, which was fabricated by Fe3O4 nanoparticle modified with β-cyclodextrin (Fe3O4@SiO2-GPTSCD), was prepared via a flexible method, including thermal decomposition, sol–gel process and ring-opening reaction of epoxy group. The structures had been characterized by fourier transform infrared spectra, transmission electron microscopy, and thermogravimetric analysis. The magnetic property of the resulting nanoparticles was kept, that they could be used for magnetic separation. Most excitingly, they showed high-efficiency catalytic activity with sodium hypochlorite and hydrogen peroxide as the oxidant in selective oxidation of benzyl alcohol, even higher than pure β-cyclodextrin (CD). It suggests that the hybrid nanoparticles are expected to be applied in more extensive fields, due to the combination of the activity of CD immobilized on the surface of nanoparticles and the characteristic of nanomaterials. 相似文献
110.
Haiyun Hou Baojuan Jiao Qingzhong Li Xinlu Lin Songtao Liu 《Journal of solution chemistry》2018,47(11):1875-1901
Over the full molar fraction range, the density, viscosity, refractive index, conductivity and pH at the temperatures (298.15, 308.15, and 318.15) K, mixing enthalpy at T?=?298.15 K, and 1H-NMR were measured for the binary mixtures of x N-methylimidazole (hereafter abbreviated to N-mim)?+?(1???x) methanol, together with ab initio calculations. The thermodynamic parameters of activation for viscous flow were calculated and analyzed. The excess molar volume, viscosity deviation, deviation for the logarithm of viscosity, refractive index deviation and the excess refractive index, excess Gibbs energy of activation of viscous flow and the molar mixing enthalpy were calculated and fitted with a Redlich–Kister equation. The partial molar mixing enthalpies and the protons’ chemical shift changes of N-mim and methanol were calculated and explained. An increase in temperature leads to the excess molar volume becoming more negative, whereas the deviations for the logarithm of viscosity, viscosity deviation and the excess Gibbs energy of activation of viscous flow become less positive; in contrast the refractive index deviation and the excess refractive index become less positive at first and then become more positive. The activation of the viscous fluid is a more ordered process. The physicochemical properties, ab initio calculations, combined with the 1H-NMR results reveal that the molecular interactions among unlike molecules is stronger than that between like ones. There is an ionization process and hydrogen bond interaction between N-mim and methanol, the predominant interaction is N-mim:methanol?=?1:1 hydrogen-bonded network, where the methyl groups of methanol and N-mim, respectively, are electron-withdrawing and electron-donating groups. 相似文献