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A Variational ODE and its Application to an Elliptic Problem

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Acta Mathematicae Applicatae Sinica 2007年第4期23卷 685-696页

作者： huan-song zhou Hong-bo Zhu Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences P.O. Box 71010 Wuhan 430071 China

In this paper, we consider the following ODE problem { （-u＂（τ）＋（N-1）（N-3）/4τ^2 ）u（τ）＋λu（τ）=f（τ,τ（1-N）/2 u）u（τ）,τ〉0, u∈H, N≥3. （P）,where f ∈ C（（0,＋∞） ×R,R）, f（τ,s） goes t... 详细信息

In this paper, we consider the following ODE problem { （-u＂（τ）＋（N-1）（N-3）/4τ^2 ）u（τ）＋λu（τ）=f（τ,τ（1-N）/2 u）u（τ）,τ〉0, u∈H, N≥3. （P）,where f ∈ C（（0,＋∞） ×R,R）, f（τ,s） goes to p（τ） and q（τ） uniformly in τ 〉 0 as s→ 0 and s→＋∞ respectively, 0≤ p（τ） ≤ q（τ） ∈L^∞（0,∞）. Moreover, for τ 〉 0, f（τ, s） is nondecreasing in s≥ 0. Some existence and non-existence of positive solutions to problem （P） are proved without assuming that p（τ） = 0 and q（τ） has a limit at infinity. Based on these results, we get the existence of positive solutions for an elliptic problem.

关键词： Elliptic equation asymptotically linear mountain pass theorem

Asymptotic Behavior of Least Energy Solutions for a Fractional Laplacian Eigenvalue Problem on R^(N)

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Acta Mathematica Sinica,English Series 2023年第4期39卷 707-727页

作者： Yun Bo WANG Xiao Yu ZENG huan song zhou School of Mathematics and Center for Nonlinear Studies Northwest UniversityXi'an 710127P.R.China Center for Mathematical Sciences Wuhan University of TechnologyWuhan 430070P.R.China

We are interested in the existence and asymptotic behavior for the least energy solutions of the following fractional eigenvalue problem (P)(-△)^(s)u+V(x)u=μu+am(x)|u|^(4s/N)u,∫_(R^(N))|u|^(2)dx=1,u∈H^(s)(R^(N)),where s∈(0,1),μ∈R,a>0,V(x)and m(x)are L^(∞)(R^(N))functions with N≥*** prove that there is a threshold a^(*)_(s)>0 such that problem(P)has a least energy solution u_(a)(x)for each a∈(0,a^(*)_(s))and u_(a)blows up,as a↗a^(*)_(s),at some point x_(0)∈R^(N),which makes V(x_(0))be the minimum and m(x_(0))be the ***,the precise blowup rates for u_(a)are obtained under suitable conditions on V(x)and m(x).

关键词： Laplacian eigenvalue problem constrained variational problem energ mates

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang Xie Wenjiao zhou huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

教育实习中师范生身份认同困境的人类学考察——一位新疆师范生的个案研究

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民族教育研究 2016年第6期27卷 46-53页

作者：宋萑周深几教育部普通高校人文社会科学重点研究基地北京师范大学教师教育研究中心北京100875

本文以师范生G的案例对师范生教育实习期间的身份问题展开讨论。G在缺乏指导教师专业指导的情况下,其身份构建中的方向很大程度上局限于与学生的互动,对学生情绪的关注大于对学生学习的关注致使其不能形成引领学生学习的专业身份。虽然... 详细信息

本文以师范生G的案例对师范生教育实习期间的身份问题展开讨论。G在缺乏指导教师专业指导的情况下,其身份构建中的方向很大程度上局限于与学生的互动,对学生情绪的关注大于对学生学习的关注致使其不能形成引领学生学习的专业身份。虽然指导教师的指导较少,但是其对学生学习的理解也引起了G的反思,在一定程度上促进了G构建关于教与学的教师实践性知识。

关键词：师范生教育实习身份认同

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一个山路引理的应用

数学学报（中文版） 2004年第1期47卷 189-196页

作者：周焕松中国科学院武汉物理与数学研究所数学物理实验室武汉430071

本文主要考虑如下形式的Dirichlet问题-△u(x)=f(x,u),x∈Ω,∈H01(Ω),其中f(x,t)∈C(Ω×R),f(x,t)/t关于t单调不减,并且当t∈R时关于x∈Ω一致趋向于某个L∞函数q(x)(此时,称f(x,t)关于t在无穷远处是渐近线性的).显然,在该条件下常用... 详细信息

本文主要考虑如下形式的Dirichlet问题-△u(x)=f(x,u),x∈Ω,∈H01(Ω),其中f(x,t)∈C(Ω×R),f(x,t)/t关于t单调不减,并且当t∈R时关于x∈Ω一致趋向于某个L∞函数q(x)(此时,称f(x,t)关于t在无穷远处是渐近线性的).显然,在该条件下常用的Ambrosetti-Rabinowitz型条件,即关于所有的|s|>M和x∈Ω,02,M>0为常数, F(x,s)=∫0s f(x,t)dt. 众所周知,条件(AR)在山路引理的应用中起着非常重要的作用.本文通过应用一种改进了的山路引理在没有条件(AR)的情况下来证明上面Dirichlet问题(P)也有正解存在。此方法也适用于f(x,t)关于t在无穷远处是超线性,即q(x)≡+∞的情形.

关键词： Dirichlet问题山路引理渐近线性共振问题

Mechanism of action of Linggui Zhugan Decoction in treating non-alcoholic fatty liver disease using untargeted metabolomics approach

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Traditional Medicine Research 2025年第2期10卷 65-76页

作者： huan Pei Ren-Lin Li Xin-Ran song Qian-Qian Wan Yu-Ming Wang Han-zhou Li Wei-Quan Xu Jia-Bao Liao Wei-Bo Wen Jing Miao huan-Tian Cui School of Basic Medicine Yunnan University of Chinese MedicineKunming 650599China School Clinical Medical College Yunnan University of Chinese MedicineKunming 650599China First School of Clinical Medicine Yunnan University of Chinese MedicineKunming 650599China School of Integrative Chinese and Western Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Pharmacy Tianjin Second People's HospitalTianjin 300192China

Background:Non-alcoholic fatty liver disease(NAFLD)is a liver disorder characterized by the accumulation and degeneration of fat in the liver cells,a condition that may further deteriorate and lead to cirrhosis and liver *** studies showed that metabolic dysfunction can promote NAFLD *** Zhugan Decoction(LGZGD)has therapeutic effects on *** mechanism of LGZGD still remains *** study was to examine the impact of LGZGD on the metabolic processes involved in the development of ***:A mice model of NAFLD was treated with *** therapeutic potential of LGZGD was evaluated by assessing the activity of transaminases,lipids levels of blood,and pathological changes in the liver of the mice model of ***,this study also evaluated the influence of LGZGD on liver inflammation and oxidative ***:The results of untargeted metabolomics analysis showed that LGZGD reduced the disordered lipid metabolism in NAFLD *** improved the oxidative stress and also reduced the levels of pro-inflammatory cytokines in the *** metabolomics analysis of liver samples revealed that LGZGD treatment improved metabolic disorders,including alanine,aspartate,glutamate,glycerophospholipid metabolism,and citrate *** RT-qPCR and Western blot results showed that LGZGD could regulate the expression of key enzymes in the metabolic pathway of the citrate cycle,including ATP-citrate lyase(ACLY),alanine-glyoxylate aminotransferase-2(AGXT2),phosphatidylethanolamine N-methyltransferase(PEMT),and succinate dehydrogenase(SDH).Conclusion:We found that LGZGD can treat NAFLD by reducing inflammatory responses,inhibiting oxidative stress,regulating alanine,aspartate,glutamate,and glycerophospholipid metabolism,and citrate cycle pathways.

关键词： NAFLD LGZGD untargeted metabolomics glycerophospholipid metabolism citrate cycle

The function-oriented precursor selection for the preparation of carbon dots

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Nano Research 2023年第8期16卷 11221-11249页

作者： Yalan Xu Chan Wang huan Zhuo Dongrun zhou Qijun song Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China

As a new type of fluorescent nanomaterials,carbon dots(CDs)have exhibited excellent photoluminescence properties with tunable emission and high quantum yields,hence they have attracted an increasing interest in diverse research *** photoluminescence performance of CDs is primarily influenced by their precursors,which directly or indirectly determine the structures and specific functions of the resultant *** this review,we aim to summarize the recent progress on synthesis of CDs using small aliphatic molecules,anilines,polyphenol,polycyclic aromatic hydrocarbons,organic dyes,or biomass as *** associations of the physical and chemical properties of the CDs with their respective precursors are comprehensively investigated,and the potential applications and future development of CDs are discussed in *** is hoped that this review will open new horizons for CDs preparation by rational selection of the precursors from the vastly available carbon sources and the critical comments presented,here could inspire and guide future research in the design of multifunctional CDs.

关键词： carbon dots precursors photoluminescence fluorophore sensing imaging

Rationalizing the impact of oxygen vacancy on polysulfide conversion kinetics for highly efficient lithium-sulfur batteries

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Journal of Energy Chemistry 2023年第12期87卷 51-60,I0003页

作者： Ya song huan Li Junfeng Li Jinyu An Jiao-Jing Shao Guangmin zhou School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSA 5005Australia Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055GuangdongChina College of Civil Engineering Guizhou UniversityGuiyang 550025GuizhouChina

The“shuttle effect”of lithium polysulfides(LiPSs)is a huge challenge for practical use of high-energydensity lithium-sulfur(Li-S)batteries,and one of the main reasons is the sluggish kinetics of sulfur *** oxides are able to expedite the sulfur electrochemistry,and the structural defects enhance the adsorption-conversion ability of metal oxides for ***,a significant research gap still remains regarding the relationship between the oxygen vacancy concentration and the adsorptivecatalytic performance of metal ***,we establish a correlation between oxygen vacancy concentration and adsorptive-catalytic properties by using tungsten oxide(WO_(x))as model *** is revealed that high-concentration oxygen vacancy is beneficial for enhancing the binding between tungsten oxide and LiPSs,reducing the energy barrier of Li_(2)S decomposition,and promoting polysulfide conversion ***,the Li-S batteries using the tungsten oxide with high-concentration oxygen vacancies deliver high initial discharge capacity of 1169 mA h g^(-1)at 0.2 C and 865 mA h g^(-1)at 2 C,low attenuation rate of 0.064%per cycle over 1100 cycles at 2 *** a high sulfur area loading of 5.34 mg cm^(-2),the Li-S batteries still exhibit high initial gravimetric capacity of 982 mA h g^(-1)at 0.1 C and areal capacity of 5.92 mA h cm^(-2).This work promotes the feasibility of defect engineering on metal oxides as an effective mean to enhance the practicality of Li-S batteries.

关键词： Shuttl eeffect Oxygen vacancy Interlayer Lithium-sulfur batteries

Low profile cavity-embedded ultra-wideband UHF array antenna with end-fire beams

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Journal of Electronic Science and Technology 2024年第2期22卷 24-35页

作者： huan He Wen-song Wang Southwest China Institute of Electronic Technology Chengdu610036China School of Electrical and Electronic Engineering Department Nanyang Technological UniversitySingapore639798Singapore

A low-profile,vertically polarized,ultra-wideband array antenna with end-fire beams operating in an ultra-high frequency(UHF)band is developed in this *** array antenna consists of 1×16 log-periodic top-hat loaded monopole antenna arrays and is feasible to embed into a shallow cavity to further reduce the array *** is introduced in the proposed antenna element to reduce profile height and the rectangular top hats are carefully designed to minimize the transverse *** results show that when the antenna array operates in a frequency range of 300 MHz-900 MHz,the end-fire radiation pattern achieves±45°scanning range in the horizontal *** prototypes of the proposed end-fire antenna element and a uniformly spaced linear array(1×2)are fabricated and *** end-fire antenna array should be suitable for airborne applications where low-profile and conformal scanning phased antenna arrays with end-fire radiations are *** design is attractive for airborne platform applications that are used to search,discover,identify,and scout the aerial target with vertically polarized beams.

关键词： End-fire radiation Low-profile Vertical polarization Log-periodic array