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Hydrogen production from steam reforming of methanol over CuO/ZnO/Al_2O_3 catalysts: Catalytic performance and kinetic modeling

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Chinese Journal of Chemical Engineering 2016年第9期24卷 1186-1194页

作者： yu wan Zhiming Zhou Zhenmin Cheng State Key Laboratory of Chemical Engineering East China University of Science and Technology

A series of CuO/ZnO/Al_2O_3, CuO/ZnO/ZrO_2/Al_2O_3 and CuO/ZnO/CeO_2/Al_2O_3 catalysts were prepared by coprecipitation and characterized by N_2 adsorption, XRD, TPR, N_2O titration and HRTEM. The catalytic performances of these catalysts for the steam reforming of methanol were evaluated in a laboratory-scale fixed-bed reactor at 0.1 MPa and temperatures between 473 and 543 K. The results showed that the catalytic activity depended greatly on the catalyst reducibility and the specific surface area of Cu. An approximate linear correlation between the catalytic activity and the Cu surface area was found for all catalysts investigated in this *** to CuO/ZnO/Al_2O_3, the ZrO_2-doped CuO/ZnO/Al_2O_3 exhibited higher activity and selectivity to CO,while the CeO_2-doped catalyst displayed lower activity and selectivity. Finally, an intrinsic kinetic study was carried out over a screened CuO/ZnO/CeO_2/Al_2O_3 catalyst in the absence of internal and external mass transfer effects. A good agreement was observed between the model-derived effluent concentrations of CO(CO_2) and the experimental data. The activation energies for the reactions of methanol-steam reforming, water-gas shift and methanol decomposition over CuO/ZnO/CeO_2/Al_2O_3 were 93.1, 85.1 and 116.5 k J·mol^(-1), respectively.

关键词： Steam reforming of methanol CuO/ZnO/Al2O3 Dopants Cu surface area Kinetics

Splitting of Operators and Operator Equations

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Acta Mathematica Sinica,English Series 2023年第6期39卷 1085-1100页

作者： Chun yuan DENG wan yu ZHANG School of Mathematics Science South China Normal UniversityGuangzhou 510631P.R.China

In this paper,we consider the splitting operators into the product of two positive *** given operators A and T∈B(H)with A≥0 and R(A)=R(T),if T can be splitted as T=AX for some positive operator X,then the existence of X and the properties of T are *** related research are the solutions of operator equations T=XAX and TX=XAX,which have some particular properties and broad applications in many *** conditions for the existence of solutions or idempotent solutions of these kinds of equations are studied and new representations of the general solutions are given.

关键词： Projection positive operator operator equation Moore-Penrose inverse

Why super sandstorm 2021 in North China?

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National Science Review 2022年第3期9卷 119-127页

作者： Zhicong Yin yu wan Yijia Zhang Huijun wang Key Laboratory of Meteorological Disaster Ministry of EducationJoint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)Nanjing University of Information Science and Technology Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of Sciences

Severe sandstorms reoccurred in the spring of 2021 after an absence for more than 10 years in North *** dust source area,located in Mongolia,suffered destructive cooling and warming in early and late winter,which loosened the land.A lack of precipitation,excessive snow melt and strong evaporation resulted in dry soil and exiguous spring vegetation.A super-strong Mongolian cyclone developed on the bare and loose ground,and easily blew and transported large amounts of sand particles into North ***,top-ranking anomalies(sea ice shift in the Barents and Kara Sea,and sea surface temperatures in the east Pacific and northwest Atlantic) were found to induce the aforementioned tremendous climate anomalies in the dust source *** es,based on large-ensemble Coupled Model Intercomparison Project Phase 6,yield results identical to the reanalysis ***,the climate variabilities at different latitudes and synoptic disturbances jointly facilitated the strongest spring sandstorm over the last decade.

关键词： sandstorm dust source Arctic sea ice La Niña cyclone

Thickness-Dependent Microstructure and its Effect on Anisotropic Mechanical Properties of Duplex Stainless Steel 2205 Multi-pass Welded Joints

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Acta Metallurgica Sinica(English Letters) 2023年第11期36卷 1883-1892页

作者： Zhilong Dong Xue-Fang Xie Jingwen Li yu wan State Key Laboratory of Heavy Oil Processing College of New EnergyChina University of Petroleum(East China)Qingdao266580China China National Offshore Oil Corporation Petrochemical Engineering Company Limited Jinan250000China

In this study,the thickness-dependent microstructural characteristics of duplex stainless steel 2205 multi-pass welded joints were first investigated by the combination of optical microscope and electron back-scattered diffraction ***,a series of tensile tests of miniature samples cut from different passes and directions were performed to analyze the thickness-dependent and anisotropic mechanical *** results demonstrate that the microstructure changed with the welded passes,i.e.,a large number of grain boundary austenite,Widmanstätten austenite and a small number of tiny intragranular austenite existed at the surface passes,while a mass of intragranular austenite were found at the middle ***,the Kurdjumov–Sachs orientation relationship was widespread at the welded *** addition,the yield and tensile strengths of the middle passes were greater than that of the surface passes due to the grain-boundary strengthening by tiny intragranular ***,due to the existence of Kurdjumov–Sachs orientation relationship,the longitudinal yield and tensile strength were greater than transverse values,particularly for the middle passes.

关键词： Duplex stainless steel Multi-pass welded joints Thickness-dependent microstructure Anisotropic mechanical properties

Effects of glucocorticoids on leukocytes:Genomic and non-genomic mechanisms

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World Journal of Clinical Cases 2022年第21期10卷 7187-7194页

作者： wan-yu Jia Jian-Jiang Zhang Department of Pediatrics The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Clinical Center of Pediatric Nephrology of Henan Province The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina

Glucocorticoids(GCs)have been widely used as immunosuppressants and antiinflammatory agents to treat a variety of autoimmune and inflammatory diseases,and they fully exert their anti-inflammatory and immune-regulating effects in the *** effect of GCs on white blood cells is an important part of their *** can cause changes in peripheral blood white blood cell counts by regulating the proliferation,differentiation,and apoptosis of white blood *** the total number of white blood cells,neutrophil counts,lymphocytes,and eosinophils increases,the counts of basic granulocytes and macrophages *** addition,GCs can regulate the activation and secretion of white blood cells,inhibit the secretion of a variety of pro-inflammatory cytokines,the expression of chemokines,and promote the production of anti-inflammatory *** patients on GC therapy,the effects of GCs on leukocytes were similar to the changes in peripheral blood caused by bacterial ***,we suggest that clinicians should be more cautious in assessing the presence of infection in children with long-term use of GCs and avoid overuse of antibiotics in the presence of elevated *** work through genomic and non-genomic mechanisms in the human body,which are mediated by GC *** recent years,studies have not fully clarified the mechanism of GCs,and further research on these mechanisms will help to develop new therapeutic strategies.

关键词： Glucocorticoid Leukocyte Count Functions Glucocorticoid receptor

Exact Solution for Jaynes-Cummings Model with Bosonic Field Nonlinearity and Strong Boson-Fermion Coupling

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Communications in Theoretical Physics 2006年第1期45卷 143-146页

作者： YANG Jin yu wan-Lun XIANG An-Ping Department of Optics and Electronics Chengdu University of Information Technology~ Chengdu 610225 China

We use Lewis Riesenfeld invariant approach to treat the modified Jaynes-Cummings models involving any forms of nonlinearty of the bosonic field when strong boson-fermion couplings are nilpotent Grassmann valued. The general state functions, time evolution operator and the time-evolution expressions for both the bosonic number and the fermionic number are presented.

关键词： nonlinear Jaynes-Cummings model invariant method exact solution

Spin injection in a ferromagnet/resonant tunneling diode heterostructure

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Journal of University of Science and Technology Beijing 2008年第5期15卷 638-643页

作者： Jin Bao Fang wan yu wang Xiaoguang Xu Yong Jiang School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The spin transport property of a ferromagnet （FM）/insulator （Ⅰ）/resonant tunneling diode （RTD） heterostructure was studied. The transmission coefficient and spin polarization in a multilayered heterostructure was calculated by a Schrdinger wave equation. An Airy function formalism approach was used to solve this equation. Based on the transfer matrix approach,the transmittivity of the structure was determined as a function of the Feimi energy and other parameters. The result shows that the spin polarization induced by the structure oscillates with the increasing Fermi energy of the FM layer. While the thickness of the RTD is reduced,the resonant peaks become broad. In the heterostructure,the spin polarization reaches as high as 40% and can be easily controlled by the external bias voltage.

关键词： spin injection resonant tunneling diode heterostructure spin polarization

Resveratrol, an activator of SIRT1, restores erectile function in streptozotocin-induced diabetic rats

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Asian Journal of Andrology 2013年第5期15卷 646-651页

作者： Wen yu Zan wan Xue-Feng Qiu yun Chen yu-Tian Dai Department of Urology Affiliated Drum Tower Hospital School of Medicine Nanjing University Nanjing 210008 China

The high incidence of erectile dysfunction （ED） in diabetes highlights a need for effective treatment strategies. Resveratrol, an activator of silent information regulator 2-related enzymes 1 （sirtuinl, SIRT1）, has received attention for its valuable effects in cancer, neurodegenerative diseases, longevity and cardiovascular disease. To explore the effects of resveratrol in diabetes-induced ED, resveratrol was administered to rats with streptozocin （65 mg kg-1）-induced diabetes. Erectile function, cavernous structure, tissue protein expression of silent information regulator 2-related enzymes 1 （sirtuinl, SIRT1）, p53 and forkhead transcription factor 0 3a （FOXO3a）, superoxide dismutase （SOD） activity and malondialdehyde （MDA） levels in the corpora cavernosa were studied. We found that SIRT1 was expressed in cavernosal tissue, and it was downregulated in the corpora of diabetic rats. The administration of resveratrol upregulated the expression of SI RT1 and restored erectile function. In contrast, resveratrol downregulated the expression of p53 and FOXO3a, which regulate apoptosis and oxidative stress. Furthermore, the resveratrol-treated group showed an improvement in smooth muscle content, SOD activity and MDA levels when compared with the diabetic group. Therefore, the ability of resveratrol to improve diabetes-induced ED is likely related to its activation of SIRT1 expression, thus causing the suppression of apoptosis and resistance towards oxidative stress.

关键词： apoptosis erectile dysfunction oxidative stress resveratrol

An overview of the 2018 second class State Natural Science Award—North China Craton:formation and revolution of the oldest continent in China

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Science Bulletin 2019年第10期64卷 641-643页

作者： yu-Sheng wan Dun-Yi Liu Biao Song Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences

The formation, composition and evolution of the oldest continental crust is the logical starting point for discussing the differentiation and development of the crust-mantle system and the tectonic evolution of the Earth. Searching for and identifying the oldest continental crust and investigating the processes and periodicity of crust formation and its subsequent development into cratons is a primary scientific topic of worldwide research [1]. The other important issues related to early Precambrian evolution include identifying tectonic divisions and determining the onset of plate tectonics. However, the rarity of preserved ancient continental crust due to its long-term reworking makes this research extremely challenging. Thus, finding and identifying the oldest rocks and zircons is the beginning of very exciting and important research. The occurrence of >3.8 Ga rocks in northern and eastern Canada, West Greenland and eastern Antarctica are difficult to access and so it is important to identify other occurrences of such rocks.

关键词： The formation oldest continental crust eastern Antarctica