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Optimizing the electronic spin state and delocalized electron of NiCo_(2)(OH)_(x)/MXene composite by interface engineering and plasma boosting oxygen evolution reaction

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Journal of Energy Chemistry 2022年第8期31卷 129-140,I0004页

作者： Jingyao Xu Xia Zhong Xiaofeng Wu Ying Wang Shouhua Feng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012JilinChina Chinese Acad sci Inst Met ResShenyang Natl Lab Mat SciShenyang 110016LiaoningChina univ sci&technol China Sch Mat Sci&EngnShenyang 110016LiaoningChina State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina

The electrocatalytic activity of transition-metal-based compounds is closely related to the electronic ***,optimizing the surface electron spin state of catalysts remains a ***,we developed a spin-state and delocalized electron regulation method to optimize oxygen evolution reaction(OER)performance by in-situ growth of NiCo_(2)(OH)_(x) using Oswald ripening and coordinating etching process on MXene and plasma treatment.X-ray absorption spectroscopy,magnetic tests and electron paramagnetic resonance reveal that the coupling of NiCo_(2)(OH)_(x) and MXene can induce remarkable spin-state transition of Co^(3+)and transition metal ions electron delocalization,plasma treatment further optimizes the 3 d orbital structure and delocalized electron *** unique Jahn-Teller phenomenon can be brought by the intermediate spin state(t2 _(g)^(5) e_(g)^(1))of Co^(3+),which benefits from the partial electron occupied *** distinct electron configuration(t2_(g)^(5) e_(g)^(1))with unpaired electrons leads to orbital degeneracy,that the adsorption free energy of intermediate species and conductivity were further *** optimized electrocatalyst exhibits excellent OER activity with an overpotential of 268 m V at 10 m A cm^(-2).DFT calculations show that plasma treatment can effectively regulate the d-band center of TMs to optimize the adsorption and improve the OER *** approach could guide the rational design and discovery of electrocatalysts with ideal electron configurations in the future.

关键词： Transition metal compounds Electronic state control of surface/interface Electron spin state Delocalized electron Electrocatalytic material

A Cumulant-Based Adaptive Detection Technique for Optical Wireless Communication Over Strong Turbulence Channels

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China Communications 2008年第1期5卷 22-27页

作者： Wang, Jin Huang, Dexiu Yuan, Xiuhua Huazhong univ sci & technol Wuhan Natl Lab Optoelect Wuhan 430074 Peoples R China

The optical wireless communication (OWC) is afading channel because of the effect of atmosphericattenuation. We introduce a cumulant-based adaptive detection technique to providehigh performance for OWC. The received signalof OWC over strong turbulence channels is assumedto be a mixture of K-distributed fading andGaussian distributed thermal noise. In order tomitigate the fading induced by turbulence, thedecision threshold-updating algorithm based onsecond and higher order cumulants is proposed,which is able to operate in an unknown turbulenceenvironment. The performance of the adaptiveprocessing scheme has been evaluated by meansof Monte Carlo simulations. It is shown that theproposed approach proves valuable for a limitednumber K of memory data.

关键词： Optical wireless communication atmospheric turbulence K-distributed adap- tive detection.

Whole Genome RNAi Screen in C. elegans Identifies CAB-1 as a Novel Regulator of DCV Secretion

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生物化学与生物物理进展 2014年第8期41卷 787-795页

作者： Xia Zhi-Ping Chen Yan Sheng Yi Yi Ya-Lan Song E-Li Xu Tao Chinese Acad sci Inst Biophys Natl Lab Biomacromol Beijing 100101 Peoples R China Huazhong univ sci & technol Coll Life Sci & Technol Wuhan 430074 Peoples R China univ Chinese Acad sci Beijing 100049 Peoples R China

内分泌细胞和神经细胞通过释放激素和神经肽类物质来响应外界刺激，而这些物质的分泌，都是通过致密核心囊泡(dense core vesicle，DCV)来实现的．但是，现阶段关于DCV的生成、转运、释放的机制很大程度上是不清楚的．在本研究中，我们... 详细信息

内分泌细胞和神经细胞通过释放激素和神经肽类物质来响应外界刺激，而这些物质的分泌，都是通过致密核心囊泡(dense core vesicle，DCV)来实现的．但是，现阶段关于DCV的生成、转运、释放的机制很大程度上是不清楚的．在本研究中，我们将线虫的排便行为和肠道分泌联系起来，并以此表型进行全基因组RNAi筛选，寻找调节DCV的新基因．我们成功筛选到了一些在肠道调节DCV生成或释放的基因．其中，CAB-1被确认为特异性调节DCV分泌的重要因子．在肠道中，cab-1突变会降低肠道DCV内容物的分泌，而在神经系统中，CAB-1的缺失也会导致DCV的标识物堆积在突触前，而突触囊泡(synaptic vesicle，SV)不受影响．

关键词：摘要编辑部编辑工作读者

Resource Allocation based on Shared Criterion in OFDMA Distributed Radio Access Network

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China Communications 2010年第1期7卷 16-22页

作者： Yang Bo Tang Youxi univ Elect sci & technol China Natl Key Lab Commun Chengdu 610054 Peoples R China

Distributed radio access network (DRAN) is a novel wireless access architecture and can solve the problem of the available spectrum scarcity in wireless communications. In this paper, we investigate resource allocation for the downlink of OFDMA DRAN. Unlike previous exclusive criterion based algorithms that allocate each subcarrier to only one user in the system, the proposed algorithms are based on shared criterion that allow each subcarrier to be allocated to multiple users through different antennas and to only one user through same antenna. First, an adaptive resource allocation algorithm based on shared criterion is proposed to maximize total system rate under each user's minimal rate and each antenna's maximal power constraints. Then we improve the above algorithm by considering the influence of the resource allocation scheme on single user. The simulation results show that the shared criterion based algorithm provide much higher total system rate than that of the exclusive criterion based algorithm at the expense of the outage performance and the fairness, while the improved algorithm based on shared criterion can achieve a good tradeoff performance.

关键词： resource allocation distributed radio access network (DRAN) orthogonal frequency division multiple access (OFDMA) shared criterion

Soft X-ray in-line holographic experiment

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Chinese science Bulletin 1998年第8期43卷 641-643页

作者： Shaoguang Yang Xingshu Xie Chengzhi Jia Yongfei Zhao Shiping Jiang Yuxuan Zhang Xiaobin Shan Xinyi Zhang univ sci & technol China Ctr Fundamental Phys Hefei 230026 Peoples R China univ sci & technol China Natl Synchrotron Radiat Lab Hefei 230029 Peoples R China

Water window" soft X-ray has some advantages in the microimaging of biological specimens. Soft X-ray holography can give us three-dimensional images of biological cells in their natural condition. Quasi-monochromatic soft X-ray from the polymonochromatic synchrotron radiation is obtained by a zone plate-pinhole linear monochromator at National Synchrotron Radiation Laboratory (NSRL) at Hefei. The pinhole is used to increase the temporal coherence of the soft X-ray, and also to increase the spatial coherence of it. An in-line holographic experiment has been finished with soft X-ray of main wavelength 4.5 nm and pinhole of diameter 0.03 mm. The magnified hologram is reconstructed with He-Ne laser. A smaller pinhole is wanted to be used to improve the coherence of the soft X-ray so as to improve the quality of the hologram.

关键词： soft X-ray microscopy in-line hologram.

ELASTICITY EFFECTS ON THE WATER IMPACT OF AN ELASTIC FLAT-BOTTOM BOX

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Journal of Hydrodynamics 2002年第2期14卷 64-70页

作者： Li, Wan-Ping Liu, Gui-Rong Chan, Eng-Song Huazhong univ. of sci. and technol. Wuhan 430074 China natl. univ. of Singapore Singapore 119260 Singapore

To elucidate the effects of elasticity the hydrodynamic impact of a 2-D flat-bottom shell box onto a water surface was investigated in detail using the finite element code Dytran. An ALE coupling algorithm was employed to handle the interactions between the box and the fluids. In this study, both air and water were treated as compressible fluids and their properties were modeled through the equation of states. Calculated results show that the air cushion plays a very important role buffering the impinging. Under the deformed concave bottom an air cushion layer will be easier to form up. For high impact speed, the pressure for the elastic box is much lower than that for the rigid box. Excited by the impact, the impinging box oscillates with about its natural frequency.

关键词： Air cushioning Compressible flow Elasticity Finite element method Impact testing Water

A Preliminary Raman Investigation of the Lead Titanate Thin Films via Sol-Gel Process

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Journal of Materials science & technology 1997年第4期13卷 306-308页

作者： Zhu, T Han, GR Zhao, GL Ding, ZS Han, ZF univ sci & technol CHINA NATL SYNCHROTRON RADIAT LABHEFEI 230026PEOPLES R CHINA ZHEJIANG univ DEPT MAT SCI & ENGNHANGZHOU 310027PEOPLES R CHINA

Raman spectra of the PbTiO3 films via sol-gel process were investigated by using a Jobin Yvon U1000 system. Compared with the Raman spectra of the PbTiO3 single crystals, Raman peaks of PbTiO3 films shift downward, which is attributed to the stress effect in the PbTiO3 films exerted by the substrate and the size effect on the Raman frequencies.

关键词： Lead compounds

Increased susceptibility to experimental steatohepatitis induced by methionine-choline deficiency in HBs-Tg mice

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Hepatobiliary & Pancreatic Diseases International 2010年第5期9卷 513-519页

作者： Fu, Miao-Miao Sun, Rui Tian, Zhi-Gang Wei, Hai-Ming univ sci & technol China Inst Immunol Sch Life Sci Hefei Natl Lab Phys Sci Microscale Hefei 230027 Peoples R China

BACKGROUND: Worldwide, about 25% of individuals with chronic hepatitis B have fatty liver disease. Lipogenic diets that are completely devoid of methionine and choline induce nonalcoholic fatty liver disease. However, no animal model of nonalcoholic steatohepatitis associated with HBV infection is available, and the influence of viral infection on nutritional hepatic steatosis is unclear. METHODS: We used HBV surface antigen transgenic mice (HBs-Tg mice), which mimic healthy human carriers with hepatitis B surface antigen. The mice were fed with a high-fat methionine-choline-deficient diet (MCD) to build a reliable rodent nutritional model of nonalcoholic steatohepatitis associated with HBV infection, and the changes in body weight and serum triglycerides were measured. Hepatocyte ballooning changes were determined by hematoxylin and eosin staining. The extent of hepatic fat accumulation was evaluated by oil red O staining. Immunohistochemical assays were performed to detect proliferating cell nuclear antigen as an index of cell proliferation. RESULTS: MCD feeding provoked systemic weight loss and liver injury. MCD feeding caused more macrovesicular fat droplets and fat accumulation in the livers of HBs-Tg mice than in wild-type C57BL/6 mice. In addition, within 30 days of MCD exposure, more PCNA-positive nuclei were found in the livers of HBs-Tg mice. CONCLUSIONS: HBs-Tg mice fed with a lipogenic MCD form more macrovesicular fat droplets earlier, coincident with more hepatocyte proliferation, resulting in the appearance of increased susceptibility to experimental steatohepatitis in these mice.

关键词： high-fat methionine-choline-deficient diet HBV surface antigen transgenic mice steatohepatitis, experimental

Synchrotron radiation photoemission study on growth of gadolinium film over Ni(110)surface

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Chinese science Bulletin 1999年第4期44卷 328-331页

作者： Faqiang Xu Junfa Zhu Yuming Sun Xianfeng Wang Erdong Lu Pengshou Xu Xinyi Zhang Shuxian Zhuang univ sci & technol China Natl Synchrotron Radiat Lab Hefei 230029 Peoples R China univ sci & technol China Dept Chem Phys Hefei 230029 Peoples R China

The growth of Gd film on Ni(110) surfaco was studied by synchrotron radiation photoemission spectroscopy and XPS techniques. It is revealed that in the coverage range of 0—0.22 nm Gd4f core level showed a single-peak structure, therefore Gd film grows over Ni(110) in the layer-by-layer mode. However, when Gd coverage was larger than 0.22, nm the Gd4f peak turned gradually into double-peak and a double-peak structure with 2.3 eV separation was formed at 1.51 nm, meanwhile similar phenomenon was observed in the Gd4d XPS spectra. It is suggested that the double-peak structure of Gd4f was derived from the growth of Gd film in cluster mode and the Gd atomic clusters may exhibit different electronic states from Gd metal owing to their special structures. The Gd4f double-peak evolved into a single-peak on annealing at 600 K, implying that Gd clusters are thermodynamically unstable.

关键词： Gd film synchrotron radiation Ni(110) surface.