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Case Studies of the Microphysical and k.nematic Structure of Summer Mesoscale Precipitation Clouds over the Eastern Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第1期41卷 97-114页

作者： Shuo JIA Jiefan YANG Hengchi lei k.y Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Three cases of microphysical characteristics and k.nematic structures in the negative temperature region of summer mesoscale cloud systems over the eastern Tibetan Plateau(TP)were investigated using X-band dual-polariz.tion *** time-height series of radar physical variables and mesoscale horiz.ntal divergence δderived by quasi-vertical profiles(QVPs)indicated that the dendritic growth layer(DGL,-20°C to-10°C)was ubiquitous,with large-value z.nes of k.(DP)(specific differential phase),z.(DR)(differential reflectivity),or both,and corresponded to various dynamic fields(ascent or descent).Ascents in the DGL of cloud systems with vigorous vertical development were coincident with large-value z.nes of z.(DR),signifying ice crystals with a large axis ratio,but with no obvious large values of k.(DP),which differs from previous *** is speculated that ascent in the DGL promoted ice crystals to undergo further growth before *** there was descent in the DGL,a high echo top corresponded to large values of k.(DP),denoting a large number concentration of ice crystals;but with the echo top descending,small values of k.(DP) *** is similar to previous results and reveals that a high echo top is conducive to the generation of ice *** ice particles fall to low levels(-10℃ to 0℃),they grow through riming,aggregation,or deposition,and may not be related to the k.nematic *** is important to note that this study was only based on a limited number of cases and that further research is therefore needed.

关键词： Tibetan Plateau polarimetric variables microphysics dendritic growth layer k.nematic structure aggregation riming

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Multiple Solutions for the k.0}n-Gordon-Maxwell System with Steep Potential Well

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 155-165页

作者： Xiao-qi LIU Chun-lei TANG School of Mathematics and Statistics Southwest UniversityChongqing 400715China

In this paper,we concern the k.0}n-Gordon-Maxwell system with steep potential well{-△u+(λa(x)+1)u-(2w+φ)φu=f(x,u),in R^3-△φ=-(w+)u^2,in R^3 Without global and local compactness,we can tell the difference of mult... 详细信息

关键词： k.0}n-Gordon-Maxwell system steep potential well multiple solutions variational methods

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Simulation of Shallow Gas Invasion Process During Deepwater Drilling and Its Control Measures

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Journal of Ocean University of China 2022年第3期21卷 707-718页

作者： lei Yani SUN Jin WANG Guangjian Department of Energy and Chemical Engineering Qingdao University of Science and TechnologyQingdao266525China Laboratory of Marine Geophysics and Georesource Institute of Deep-Sea Science and EngineeringChinese Academy of SciencesSanya572000China Southern Marine Science and Engineering Guangdong Laboratory(z.uhai) Zhuhai519080China

Shallow gas is considered one of the most serious geological haz.rds in deepwater drilling because it has the characteristics of suddenness and is difficult to deal *** perform a quantitative evaluation of shallow gas risk.during deepwater drilling,a numerical model for calculating gas invasion volume is established based on gas-water two-phase flow *** model considers the effect of the dynamic drilling process,and the influencing factors which affect the gas invasion volume are *** indicate that the gas invasion rate and accumulated gas invasion volume increase with increasing bottom-hole pressure difference.A linear relationship exists between gas invasion volume and bottom-hole pressure *** duration of gas invasion increases as the shallow gas z.ne thick.ess increases,and the accumulated gas invasion volume grows as shallow gas z.ne thick.ess *** increase in formation permeability,water depth,and rate of penetration will enhance the gas invasion ***,these three factors can hardly affect the accumulated gas invasion *** gas flow rate increases significantly with increasing burial depth of shallow *** the basis of influencing factor analysis,a series of methods that consider different risk.levels is proposed to control shallow gas,which can provide a reference for the prevention of shallow gas disasters during deepwater drilling.

关键词： shallow gas deepwater drilling dynamic drilling process gas invasion gas invasion rate

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Titanium-z.rconium-phosphonate hybrid film on 6061 aluminum alloy

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Acta Metallurgica Sinica(English Letters) 2011年第1期24卷 18-22页

作者： Shuanghong WANG lei WANG Changsheng LIU k.y Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern UniversityShenyang 110819 China

Three titanium-z.rconium-phosphonate hybrid films were formed on AA6061 alu- minum alloy by immersing in fluorotitanic acid and fluoroz.rconic acid based solution containing different phosphonic acids for protective coatings of aluminium alloy. The corrosion resistance of three hybrid films as the substitute for chromate film were evaluated and compared. The neutral salt spray test was explored, the immersion test was conducted and electrochemical test was also executed. The hybrid films exhibited well-pleasing corrosion resistance and adhesion to epoxy resin paints. It was found out that the hybrid films could efficiently be a substitute for chromate based primer over aluminium alloy.

关键词： Aluminum alloy Titanium-z.rconium-phosphonate Hybridfilm Corrosion resistance

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Heteroatom-Induced Accelerated k.netics on Nick.l Selenide for Highly Efficient Hydraz.ne-Assisted Water Splitting and z.-Hydraz.ne Battery

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Nano-Micro Letters 2023年第9期15卷 492-504页

作者： Hao-Yu Wang lei Wang Jin-Tao Ren Wen-Wen Tian Ming-lei Sun z.ong-Yong Yuan School of Materials Science and Engineering Smart Sensing Interdisciplinary Science CenterNankai UniversityTianjin 300350People’s Republic of China k.y Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071People’s Republic of China

Hydraz.ne-assisted water electrolysis is a promising energy conversion technology for highly efficient hydrogen *** design of bifunctional electrocatalysts,which can simultaneously accelerate hydrogen evolution reaction(HER)/hydraz.ne oxidation reaction(Hz.R)k.netics,is the k.y ***,we demonstrate the development of ultrathin P/Fe co-doped NiSe_(2) nanosheets supported on modified Ni foam(P/Fe-NiSe_(2)) synthesiz.d through a facile electrodeposition process and subsequent heat *** on electrochemical measurements,characteriz.tions,and density functional theory calculations,a favorable“2+2”reaction mechanism with a two-step HER process and a two-step Hz.R step was fully proved and the specific effect of P doping on Hz.R k.netics was investigated.P/Fe-NiSe_(2) thus yields an impressive electrocatalytic performance,delivering a high current density of 100 mA cm^(−2) with potentials of−168 and 200 mV for HER and Hz.R,***,P/Fe-NiSe_(2) can work.efficiently for hydraz.ne-assisted water electrolysis and z.-Hydraz.ne(z.-Hz.battery,mak.ng it promising for practical application.

关键词： Water electrolysis Hydrogen production Hydraz.ne oxidation Bifunctional electrocatalyst Heteroatom doping

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The Stable Carbon Isotopic Compositions of n-Alk.nes in Sediments of the Bohai and North Yellow Seas: Implications for Sources of Sedimentary Organic Matter

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Journal of Ocean University of China 2021年第2期20卷 340-348页

作者： DANG Tianxiang CAO Yunyun XING lei k.y Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China

Stable carbon isotopic compositions of n-alk.nes in surface sediments of the Bohai and North Yellow Seas were investigated to elucidate sources of sedimentary organic matter in these seas. The long-chain n-alk.nes in surface sediments are predominantly long-chain C27, C29, and C31 types, with obvious odd carbon predominance. The δ13 C values of long-chain n-C27, n-C29, and n-C31 alk.nes are-30.8% ± 0.5‰,-31.9% ± 0.6‰, and-32.1% ± 1.0‰, respectively, within the range of n-alk.nes of C3 terrestrial higher plants. This suggests that sedimentary n-alk.nes are derived mainly from terrestrial higher plants. Compound-specific carbon isotopic analysis of long-chain n-alk.nes indicates that C3 terrestrial higher plants predominate(64%–79%), with angiosperms being the main contributors. The n-alk.ne δ13 C values indicate that mid-chain n-alk.nes in sediments are derived mainly from aquatic emergent macrophytes, with significant petroleum pollution and bacterial degradation sources for short-chain n-alk.nes.

关键词： biomark.r carbon isotopes n-alk.nes Bohai Sea North Yellow Sea

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Automorphisms of a Class of Finite p-groups with a Cyclic Derived Subgroup

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Acta Mathematica Sinica,English Series 2021年第6期37卷 926-940页

作者： Yu lei WANG He Guo LIU Department of Mathematics He’nan University of TechnologyZhengzhou 450001P.R.China Department of Mathematics Hubei UniversityWuhan 430062P.R.China

Let p be an odd prime,and let k.be a nonz.ro nature *** that nonabelian group G is a central extension as follows1→G’→G→z.(pk.×…×z.(pk.,where G’≌z.k.andζG/G’is a,direct factor of G/G’.Then G is a central product of an extraspecial pk.roup E andζ***|E|=p(2n+1)k.and|ζG|=p(m+1)*** that the exponents of E andζG are pk.l and pk.r,respectively,where 0≤l,r≤*** AutG’G be the normal subgroup of Aut G consisting of all elements of Aut G which act trivially on the derived subgroup G’,let AutG/ζG,ζG G be the normal subgroup of Aut G consisting of all central automorphisms of G which also act trivially on the centerζG and let AutG/ζG,ζG/G’G be the normal subgroup of Aut G consisting of all central automorphisms of G which also act trivially onζG/G’.Then(ⅰ)The group extension 1→Aut G’→Aut G→Aut G’→1 is split.(ⅱ)AutG’G/AutG/ζG,ζG G≌G1×G2,where Sp(2n-2,z.k.■H≤G1≤Sp(2n,z.k.,H is an extraspecial pk.group of order p(2n-1)k.and(GL(m-1,z.k.■z.k.m-1)■z.k.m)≤G2≤GL(m,z.k.■z.k.m).In particular,G1=Sp(2n-2,z.k.■H if and only if l=k.and r=0;G1=Sp(2n,z.x)if and only if l≤r;G2=(GL(m-1,z.k.■z.k.m-1)■z.k.m)if and only if r=k.G2=GL(m,z.k.■z.k.(m))if and only if r=0.(ⅲ)AutG’G/Aut G/ζG,ζG/G’G≌G1×G3,where G1 is defined in(ⅱ);GL(ml,z.k.■z.k.m-1)≤G3≤GL(n,z.k..In particular,G3=GL(m-1,z.k.■z.k.m-1)if and only if r=k.G3=GL(m,z.k.if and only if r=0.(ⅳ)AntG/ζG,ζG/G’G≌AutG/ζG,ζG/G’G■z.k.m),If m=0,then AntG/ζG,ζG/G’G=Inn G≌z.k.2n);If m>0,then AntG/ζG,ζG/G’G≌z.k.2nm)×z.k.r(2n),and AutG/ζG,ζG G/Inn G≌z.k.(2n(m-1))×z.k.r(2n).

关键词： Automorphism p-group cyclic derived subgroup symplectic group

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The Isomorphism Problem of Normaliz.d Unit Groups of Group Algebras of a Class of Finite 2-groups

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Acta Mathematica Sinica,English Series 2023年第11期39卷 2275-2282页

作者： Yu lei WANG He Guo LIU Department of Mathematics He’nan University of TechnologyZhengzhou 450001P.R.China Department of Mathematics Hainan UniversityHaikou 570228P.R.China

Let p be a prime and F_p be a finite field of p *** F_(pG)denote the group algebra of the finite p-group G over the field F_(p)and V(F_(pG))denote the group of normaliz.d units in F_(pG).Suppose that G and H are finite p-groups given by a central extension of the form 1→z.(p)^(m)→G→z.(p)×···×z.(p)→1 and G'≌z.(p),m≥*** V(F_(p)G)≌V(F_(p)H)if and only if G≌*** and Bovdi only solved the isomorphism problem when p is *** this paper,the case p=2 is determined.

关键词： isomorphism problem normaliz.d unit Frattini subgroup finite 2-group

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Science Letters:Hydrothermal production of formic and acetic acids from syringol

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Journal of z.ejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 613-618页

作者： Lu-ting PAN z.eng SHEN lei WU Ya-lei z.ANG Xue-fei z.OU Fang-ming JIN MOE Key Laboratory of Yangtze River Water Environment State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and Engineering Tongji University Shanghai 200092 China

The production of formic and acetic acids （or salts） by hydrothermal oxidation of syringol, a model compound for lignin, was investigated using a batch reactor. Results show that the highest yields of formic and acetic acids were, respectively, 59.6% and 11.3% at the reaction condition of 0.5 mol/L NaOH, 120% H2O2 supply and 280 ℃. These results will inform studies aiming to develop more enviromnental friendly lignin conversion processes by obtaining products beyond a CO2 end product.

关键词： Lignin Syringol Formic acid. Acetic acid. Hvdrothermal process

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Layer z.rconogermanate——(H_2DETA)[z.Ge_3O_8F_2] Showing Odd 3MR and 7MR

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Chemical Research in Chinese Universities 2009年第3期25卷 282-285页

作者： LI Ya-feng SUN Jin-xu WU lei-lei TIAN Yong WANG Dao-wu z.ANG Long WANG lei School of Chemical Engineering Changchun University of Technology Changchun 130012 P. R. China College of Chemistry and Molecular Engineering Qingdao University of Science ＆ Technology Qingdao 266042 P. R. China

A layered z.rconogermanate, （H2DETA）[z.Ge3O8F2]（1）, was hydro（solvo）thermally synthesiz.d with diethylenetriamine（DETA） as template, and structurally determined by X-ray single-crystal diffraction. Compound 1 crystalliz.d in the monoclinic space group P21/c with data of unit cell： a=0.7644（2） nm, b=1.1235（2） nm, c=1.6860（3） nm, V=1.4479（5） nm^3,/a（Mo k.）=6.931 mm^-1, z.4, R1=0.0402 for 3236 reflections with Fo〉2σ（Fo）. The structure of compound I was formed by alternatively pack.ng the inorganic layer of z.Ge3O8F2 and H2DETA templated molecules along （001） direction. It was worth pointing out that the odd bifurcated 7MR nets were surrounded by odd 3MR. The protonated and disordered H2DETA cations not only balanced the superfluous charges of framework.but also stabiliz.d the structure of compound 1 by the hydrogen bond between -NH3 group and oxygen on the framework. Furthermore, IR and TG were utiliz.d to characteriz. the structure and thermal stability, respectively.

关键词： Germanate Hydrothermal synthesis Structure

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