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181.
Dr. Jia Wang Xuhui Liu Dr. Chunxu Wang Wanyi Zhang Prof. Zhengkun Qin 《ChemistryOpen》2022,11(2):e202100208
The spin polarization of carbon nanomaterials is crucial to design spintronic devices. In this paper, the first-principles is used to study the electronic properties of two defect asymmetric structures, Cap-(9, 0)-Def [6, 6] and Cap-(9, 0)-Def [5, 6]. We found that the ground state of Cap-(9, 0)-Def [6, 6] is sextet and the ground state of Cap-(9, 0)-Def [5, 6] is quartet, and the former has a lower energy. In addition, compared with Cap-(9, 0) CNTs, the C adatom on C30 causes spin polarization phenomenon and Cap-(9, 0)-Def [6, 6] has more spin electrons than Cap-(9, 0)-Def [5, 6] structure. Moreover, different adsorb defects reveal different electron accumulation. This finding shows that spin polarization of the asymmetric structure can be adjusted by introducing adatom defects. 相似文献
182.
The study of multiple complex catalytic mechanisms is currently one of the great scientific issues for the application of high-energy solid propellants. Two novel heterobimetallic metal-organic frameworks (MOFs), Ba4Pb4(CH3CO2)8 [(CH6CO2)4Pb](CH3CO2)4 (PbBa-MOF) and Ba2Ni(CO2H)6(OH2)4 (NiBa-MOF), were prepared via the solvothermal method, and their structures and composition were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FTIR) techniques and N2 adsorption/desorption experiment. The thermal decomposition characteristics of the two MOFs and their catalytic performances on the hexanitro hexaazaisowurtzitane (CL-20) thermolysis were also studied by differential scanning calorimetr (DSC) and thermogravimetric-fourier transform infrared spectroscopy-mass spectrum (TG-FTIR-MS) methods. The results showed that the NiBa-MOF presented a lower initial decomposition temperature than the PbBa-MOF, and the difference of the MOFs structures affected the starting point of thermal decomposition. Compared with the pure CL-20, the thermolysis peak temperature and apparent activation energy (Ea) of the CL-20/PbBa-MOF mixture were decreased by 2.2 °C and 23.76 kJ?mol?1, respectively. The Ea of CL-20/NiBa-MOF mixture was lower and 42.01 kJ?mol?1, indicating the better catalytic activity of NiBa-MOF. The thermolysis catalytic mechanisms were studied by analyzing the transformation of gas products during the pyrolysis of mixtures. The effect of these two MOFs on the CL-20 thermolysis is primarily owing to the strong attraction of metal cations to electronics, bimetallic synergistic catalysis, and the release of active free radicals. Furthermore, the laser ignition and flame propagation features showed that these two MOFs reduced the minimum ignition power density and ignition delay time of the CL-20, and the flame becomes brighter and more luminous. The influence of the two MOFs on the flame bright spot of CL-20 based mixtures was described. 相似文献
183.
Dr. Xiaohui Zhang Neng Qin Dr. Hongbo Cui Prof. Guijian Guan Prof. Ming-Yong Han 《化学:亚洲杂志》2021,16(20):3038-3054
As a promising technique to potentially address the energy crisis and environmental issues, photocatalysis has been reported widely to exhibit various outstanding behaviors in production of new fuels/chemicals and treatment of contaminants. The photocatalytic performance is extremely dependent on the used photocatalysts, so that the design and preparation of efficient photocatalysts are critically important for significantly improving the photocatalytic activity. Among various strategies, the hybridization of metal with semiconductors has recently been attracting more and more research interest owing to their expended spectral absorption, promoted transferring rate of charge carriers and Plasmon-enhanced effect. In this minireview, the metal-facilitated hybrid photocatalysts are overviewed comprehensively to first reveal unique functions of metals in improvement of photoactivity and summarize the emerging metal-involved hybrid systems. Subsequently, the synthetic methods towards hybrid photocatalysts are introduced and their practical applications are emphasized in environmental remediation including degradation of organic pollutants, conversion of harmful gases, treatment of heavy metal ions and sterilization of bacteria. At the end, the challenges for industrializing these hybrid photocatalysts are discussed carefully and future development is suggested rationally. 相似文献
184.
Xingge Wu Zhigang Zhang Zhiyong He Zhaojun Wang Fang Qin Maomao Zeng Jie Chen 《Molecules (Basel, Switzerland)》2021,26(5)
The aim of this research was to investigate the effect of the number of freeze–thaw cycles (0, 1, 3, 5, and 7) on porcine longissimus protein and lipid oxidation, as well as changes in heterocyclic aromatic amines (HAAs) and advanced glycation end products (AGEs) and their precursors. We analyzed the relationship among HAAs, AGEs, oxidation, and precursors and found the following results after seven freeze–thaw cycles. The HAAs, Norharman and Harman, were 20.33% and 16.67% higher, respectively. The AGEs, Nε-carboxyethyllysine (CEL) and Nε-carboxymethyllysine (CML), were 11.81% and 14.02% higher, respectively. Glucose, creatine, and creatinine were reduced by 33.92%, 5.93%, and 1.12%, respectively after seven freeze–thaw cycles. Norharman was significantly correlated with thiobarbituric acid reactive substances (TBARS; r2 = 0.910) and glucose (r2 = −0.914). Harman was significantly correlated to TBARS (r2 = 0.951), carbonyl (r2 = 0.990), and glucose (r2 = −0.920). CEL was correlated to TBARS (r2 = 0.992) and carbonyl (r2 = 0.933). These changes suggest that oxidation and the Maillard reaction during freeze–thaw cycles promote HAA and AGE production in raw pork. 相似文献
185.
Qin Shun-Shun Liu Jing-Long Hu Feng Jia Ai-Quan Xu Chao Zhang Qian-Feng 《Journal of Cluster Science》2021,32(6):1593-1599
Journal of Cluster Science - Interaction of [Pb(SiPr)2]n with 1.5 equiv. of AgNO3 in DMF under aerobic conditions at room temperature gave a cationic lead-centered thiolate cluster... 相似文献
186.
WeiPing Liu ZhiHong Li JiangJun He XiaoDong Tang Gang Lian Zhu An JianJun Chang Han Chen QingHao Chen XiongJun Chen ZhiJun Chen BaoQun Cui XianChao Du ChangBo Fu Lin Gan Bing Guo GuoZhu He Alexander Heger SuQing Hou HanXiong Huang Ning Huang BaoLu Jia LiYang Jiang Shigeru Kubono JianMin Li KuoAng Li Tao Li YunJu Li Maria Lugaro XiaoBing Luo HongYi Ma ShaoBo Ma DongMing Mei YongZhong Qian JiuChang Qin Jie Ren YangPing Shen Jun Su LiangTing Sun WanPeng Tan Isao Tanihata Shuo Wang Peng Wang YouBao Wang Qi Wu ShiWei Xu ShengQuan Yan LiTao Yang Yao Yang XiangQing Yu Qian Yue Sheng Zeng HuanYu Zhang Hui Zhang LiYong Zhang NingTao Zhang QiWei Zhang Tao Zhang XiaoPeng Zhang XueZhen Zhang ZiMing Zhang Wei Zhao Zuo Zhao Chao Zhou JUNA Collaboration 《中国科学:物理学 力学 天文学(英文版)》2016,59(4):642001
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of~(25)Mg(p,γ)~(26)Al,~(19)F(p,α)~(16)O,~(13)C(α,n)~(16)O and ~(12)C(α,γ)~(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given. 相似文献
187.
Sharp leading edges with a millimeter-scale radius are required for hypersonic vehicles from aerodynamic reasons. However, with the leading edges being so sharp, stagnation regions at wing and tail leading edges suffer a hostile thermal environment. Therefore, a high-temperature heat pipe is considered to be integrated into the structure of the leading edge to reduce the temperature of the stagnation point. In this paper, a superalloy-refractory composite-container-“wall” combined with the wick and working fluid structure is proposed, which is proved to be a feasible design of a heat pipe for the semi-passive thermal protection system (TPS). The effects of different material of the exterior surface on the temperature distributions are investigated. The effect of the half wedge angle, the design length and porosity of the wick is also investigated to find the effect of the geometry of the structure of the leading edge on the operation of the heat pipe. 相似文献
188.
We report the dependence of Brillouin linewidths on the pump power below the threshold of Brillouin lasing in a silica fiber. The Stokes Brillouin shift in a silica fiber is nearly unchanged, and its linewidth decreases with increasing pump power. However, the anti-Stokes Brillouin shift becomes smaller and its linewidth larger with increasing pump power. We explain these experimental results by the distributed fluctuating source model. 相似文献
189.
Chromatographia - In this study, a poly(glycidyl methacrylate) nanoparticle (PGMA NP)-coated column system with two antibiotics as selector was constructed for enantioseparation. The PGMA NP... 相似文献
190.
Yufeng Cao Yanmei Chen Zhecheng Zhang Jin Wang Xiaolei Yuan Qin Zhao Yue Ding Yong Yao 《中国化学快报》2021,32(1):349-352
In this communication,a new supramolecualr amphiphile was successfully constructed based on water soluble pillar[5]arene and a unique guest which contain a CO2 responsive tertiary amine unit and a UV responsive coumarin group.When guest molecule 1 dispersed in water,it self-assembled into sheet-like structures.Upon bubbling CO2,1 transformed into 1 H due to the tertiary amine unit was protonated,accompany the nano-sheets transformed into vesicles.Further irradiation of 1 H with 365 nm light for 3 h,the coumarin group reacted with each other to form bola-type amphiphie 2 H.In this case,vesicles collapsed and re-assembled into nano-tubes.However,when addition of WPS into the solution of 1 H,the vesicles transformed into micelles,this is due to the formation of supramolecular amphiphile WP5&1 H.Upon irradiation of WP5&1 H with 365 nm light for 3 h,nano-ribbons observed instead of micelles in the solution.Notably,nanotubes from 2 H could also transform into nano-ribbons after adding WPS.The selfassembly process and the resultant assemblies were characterized by TEM,SEM,DLS,SAXS and NMR technologies.Due to both CO2 and light are "green" for living organisms,we anticipated our system can offer the possibilities in "on demand" drug absorption and release. 相似文献