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排序方式: 共有1321条查询结果,搜索用时 15 毫秒
1.
X-ray emission for Ar11+ ions impacting on various targets in the collisions near the Bohr velocity 下载免费PDF全文
Xian-Ming Zhou 《中国物理 B》2021,30(8):83201-083201
X-ray emission from the collisions of 3 MeV Ar11+ ions with V, Fe, Co, Ni, Cu, and Zn is investigated. Both the x-rays of the target atom and projectile are observed simultaneously. The x-ray yield is extracted from the original count. The inner-shell ionization cross section is estimated by the binary encounter approximation model and compared with the experimental result. The remarkable result is that the Ar K-shell x-ray yield is diminished with the target atomic number increasing, which is completely opposite to the theoretical calculation. That is interpreted by the competitive consumption of the energy loss for the ionization of inner-shell electrons between the projectile and target atom. 相似文献
2.
Na Wang Hang Yao Qi Tao Jing Sun Hao Ma Yang Wang ChengCheng Zhou Hongying Fan Hongxia Shao Aijian Qin Dawei Su Chenyin Wang Hui Chong 《中国化学快报》2022,33(1):252-256
Two amphiphilic TPE E/Z isomers with aggregation induced emission(AIE) property have been synthesized and characterized. The logarithmic fluorescent intensity of the two molecules was in positive relationship with logarithmic viscosity of liquid. To note, the Z-TPE isomer exhibited more sensitivity in the viscosity of liquid sensing in comparison with the corresponding E-TPE counterpart(around 1.80 folds).Furthermore, two molecules could be used as fluorescent sensors for mechanical properties(v... 相似文献
3.
We investigate a (2+1)-dimensional shallow water wave equation and describe its nonlinear dynamical behaviors in physics. Based on the N-soliton solutions, the higher-order fissionable and fusionable waves, fissionable or fusionable waves mixed with soliton molecular and breather waves can be obtained by various constraints of special parameters. At the same time, by the long wave limit method, the interaction waves between fissionable or fusionable waves with higher-order lumps are acquired. Combined with the dynamic figures of the waves, the properties of the solution are deeply studied to reveal the physical significance of the waves. 相似文献
4.
A novel ZnCo2O4/Bi2O3 heterojunction photocatalyst was prepared via balling method. The enhanced photocatalytic activity is mainly attributed to the broad photoabsorption and low recombination rate of photogenerated electron-hole pairs, which is driven by the photogenerated potential difference formed at the ZnCo2O4/Bi2O3 heterojunction interface. 相似文献
5.
Hao Niu Xue Yang Qian Wang Xiaoyan Jing Kui Cheng Kai Zhu Ke Ye Guiling Wang Dianxue Cao Jun Yan 《Journal of Energy Chemistry》2020,(7):105-113,I0004
It is highly desirable to design and synthesize two-dimensional nanostructured electrode materials with high electrical conductivity,large electrolyte-accessible surface area and more exposed active sites for energy storage applications.Herein,MXene/Co Al-LDH heterostructure has been prepared through electrostatic ordered hetero-assembly of monolayer MXene and edge-rich Co Al-LDH nanosheets in a faceto-face manner on molecular-scale for supercapacitor applications.Benefiting from the unique structure,strong interfacial interaction and synergistic effects between MXene and Co Al-LDH nanosheets,the electrical conductivity and exposed electrolyte-accessible active sites are significantly enhanced.The asprepared MXene/Co Al-LDH-80%(ML-80)film exhibits high volumetric capacity of 2472 C cm-3 in 3 M KOH electrolyte with high rate capability of 70.6%at 20 A g-1.Notably,to the best of our knowledge,the high volumetric capacity is the highest among other previously reported values for supercapacitors in aqueous electrolytes.Furthermore,our asymmetric supercapacitor device fabricated with ML-80 and MXene/graphene composite as cathode and anode,respectively,exhibits impressive volumetric energy density of 85.4 Wh L-1 with impressive cycling stability of 94.4%retention ratio after 30,000 continuous charge/discharge cycles. 相似文献
6.
Rational design of highly efficient and durable electrocatalysts with low cost to replace noblemetal based catalysts for seawater electrolysis is extremely desirable, but challenging. In this work, we demonstrate a rapid electrodeposition method by growing P-Ni4Mo on the surface of the copper foam(CF)substrate to synthesize an efficient seawater electrolysis catalyst(P-Ni4Mo/CF). The catalyst exhibited considerable HER performance and stability in alkaline seawater, with th... 相似文献
7.
To enhance transmission efficiency of Pancharatnam–Berry (PB) phase metasurfaces, multilayer splitring resonators were proposed to develop encoding sequences. As per the generalized Snell’s law, the deflection angle of the PB phase encoding metasurfaces depends on the metasurface period’s size. Therefore, it is impossible to design an infinitesimal metasurface unit; consequently, the continuous transmission scattering angle cannot be obtained. In digital signal processing, this study introduces the Fourier convolution principle on encoding metasurface sequences to freely control the transmitted scattering angles. Both addition and subtraction operations between two different encoding sequences were then performed to achieve the continuous variation of the scattering angle. Furthermore, we established that the Fourier convolution principle can be applied to the checkerboard coded metasurfaces. 相似文献
8.
Wei Liu Pengbo Zhai Shengjian Qin Jing Xiao Yi Wei Weiwei Yang Shiqiang Cui Qian Chen Chunqiao Jin Shubin Yang Yongji Gong 《Journal of Energy Chemistry》2021,(5):463-469
Li metal,possessing advantages of high theoretical specific capacity and low electrochemical potential,is regarded as the most promising anode material for next-generation batteries.However,despite decades of intensive research,its practical application is still hindered by safety hazard and low Coulombic efficiency,which is primarily caused by dendritic Li deposition.To address this issue,restraining dendrite growth at the nucleation stage is deemed as the most effective method.By utilizing the difference of electronegativity between boron atoms and carbon atoms,carbon atoms around boron atoms in boron-doped graphene(BG)turn into lithiophilic sites,which can enhance the adsorption capacity to Li+at the nucleation stage.Consequently,an ultralow overpotential of 10 mV at a current density of 0.5 mA/cm2 and a high average Coulombic efficiency of 98.54%over more than 140 cycles with an areal capacity of 2 mAh/cm2 at a current density of 1 m A/cm2 were achieved.BG-Li|LiFePO4 full cells delivered a long lifespan of480 cycles at 0.5 C and excellent rate capability.This work provides a novel method for rational design of dendrite-free Li metal batteries by regulating nucleation process. 相似文献
9.
Zhao-Yang Yuan Zhen-Xing Cao Rui Wu Hui Li Qiong-Jun Xu Hai-Tao Wu Jing Zheng Jin-Rong Wu 《高分子科学》2023,(2):250-257
Recently, numerous mechanically robust synthetic hydrogels have been created. However, unlike natural loading-bearing materials such as cartilages and muscles, most hydrogels have inherently contradictory requirements, obstructing the design of hydrogels with characteristics of robustness and rapid self-recoverability. Herein, we present a facile strategy for constructing mechanically robust and rapidly self-recoverable hydrogels. The linear poly(acrylamide-co-itaconic acid) chains crosslink via... 相似文献
10.
Jian-Hong Gao Lin-Hua Zhang Hao Shen Feng-Bo Sun Xiang Gao Yan-Jie Sun Xin-Zhu Tong Jing Wen Peng-Cheng Li Di Wu Jian-Long Xia Zhi-Tian Liu 《高分子科学》2023,(11):1686-1694
Perylene-3,4-(dicarboxylic monoimide)-9,10-(dicarboxylic monoanhydrate)(PIA) is one key intermediate to construct functionalized perylene diimides(PDIs) for various applications. However, the difficulty in synthesizing chlorinated PIA hinders the study of chlorinated PDIbased materials. Although chlorination has been widely used to modify the properties of organic semiconductors. We successfully synthesize chlorinated PIA via a simple hydrolysis reaction using LiOH as the base, then a PDI dimer ... 相似文献