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Journal of Environmental Sciences 2024年第5期139卷 12-22页

作者： Yi Yuan Wen-Long wang Zhi-Wei wang Jin wang Qian-Yuan Wu Key Laboratory of Microorganism Application and Risk Control of Shenzhen Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyInstitute of Environment and EcologyShenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Shenzhen Environmental Science and New Energy Technology Engineering Laboratory Tsinghua-Berkeley Shenzhen InstituteShenzhen 518055China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071China

Carbon nitride has been extensively used as a visible-light photocatalyst,but it has the disadvantages of a low specific surface area,rapid electron-hole recombination,and relatively low light *** this study,single-atom Ag was successfully anchored on ultrathin carbon nitride(UTCN)via thermal polymerization,the catalyst obtained is called *** Ag hardly changed the carbon nitride's layered and porous physical *** exhibited efficient visible-light photocatalytic performances in the degradation of various recalcitrant pollutants,eliminations of 85% were achieved by visible-light irradiation for *** with Ag improved the photocatalytic performance of UTCN by narrowing the forbidden band gap from 2.49 to 2.36 e V and suppressing electron-hole pair *** addition,Ag doping facilitated O_(2) adsorption on UTCN by decreasing the adsorption energy from -0.2 to -2.22 e V and favored the formation of O_(2)^(·-).Electron spin resonance and radical-quenching experiments showed that O_(2)^(·-)was the major reactive species in the degradation of Acetaminophen(paracetamol,APAP).

关键词： Ag single atom Carbon nitride Photocatalysis Visible light Adsorption energy Reactive species

The role of a novel antibacterial substance,cyclic opine-producing Lacticaseibacillus rhamnosus LS8 in ameliorating ulcerative colitis:a fecal microbiota transplantation study

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Food Science and Human Wellness 2024年第2期13卷 778-790页

作者： Tao wang Shuang wang Shuchen Dong Ruiling wang Shuxuan wang Jie Yang Xin wang Xin Lü College of Food Science and Engineering Northwest Agriculture and Forestry UniversityYangling 712100China Faculty of Food Science and Engineering Kunming University of Science and TechnologyKunming 650500China School of Life Science and Technology Xinjiang UniversityUrumqi 830046China

Intestinal microbiota imbalance may worsen the progression of ulcerative colitis(UC).Lacticaseibacillus rhamnosus LS8(LR)has the potential ability to regulate microbiota through producing a novel antibacterial substance,cyclic opine:*** study aimed to investigate whether LR could ameliorate dextran sulfate sodium-induced UC in mice via modulating intestinal microbiota using fecal microbiota transplantation(FMT)*** results showed that both LR and FMT attenuated UC as evidenced by 1)alleviating disease activity index and colonic pathology;2)up-regulating MUCs and tight junction proteins;3)increasing oxidative mediators and decreasing antioxidant mediators;4)down-regulating proinflammatory cytokines and *** results were mainly attributable to the microbiota-regulating effect of LR,including increasing beneficial bacteria(like Akkermansia)and its related SCFAs,while decreasing harmful bacteria(like Proteobacteria)and its related LPS,thereby suppressing the hyperactivation of TLR4/NF-κB ***,LR can alleviate UC and is a potential dietary supplement to attenuate UC.

关键词： Gut barrier Gut microbiota Fecal microbiota transplantation Lacticaseibacillus rhamnosus Oxidative stress Ulcerative colitis

Continuous-wave operation of 1550 nm low-threshold triple-lattice photonic-crystal surface-emitting lasers

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Light(Science & Applications) 2024年第3期13卷 446-453页

作者： Ziye wang Xia Liu Pinyao wang Huanyu Lu Bo Meng Wei Zhang Lijie wang Yanjing wang Cunzhu Tong State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Central Research Institute Planning Dept 2012 LabsHuawei Technologies Company Ltd.Shenzhen 518129China

Benefitting from narrow beam divergence,photonic crystal surface-emitting lasers are expected to play an essential role in the ever-growing fields of optical communication and light detection and *** operating with 1.55μm wavelengths have attracted particular attention due to their minimum fiber loss and high eye-safe ***,high interband absorption significantly decreases their performance at this 1.55μm ***,stronger optical feedback is needed to reduce their threshold and thus improve the output *** this goal,photonic-crystal resonators with deep holes and high dielectric contrast are often ***,the relevant techniques for high-contrast photonic crystals inevitably complicate fabrication and reduce the final *** this paper,we demonstrate the first continuous-wave operation of 1.55μm photonic-crystal surface-emitting lasers by using a‘triple-lattice photonic-crystal resonator’,which superimposes three lattice point groups to increase the strength of in-plane optical *** this geometry,the in-plane 180°coupling can be enhanced threefold compared to the normal single-lattice *** theoretical and experimental investigations demonstrate the much lower threshold current density of this structure compared to‘single-lattice’and‘double-lattice’photonic-crystal resonators,verifying our design *** findings provide a new strategy for photonic crystal laser miniaturization,which is crucial for realizing their use in future high-speed applications.

关键词： resonator crystal lattice

STABILITY AND CONVERGENCE OF STEPSIZE-DEPENDENT LINEAR MULTISTEP METHODS FOR NONLINEAR DISSIPATIVE EVOLUTION EQUATIONS IN BANACH SPACE

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Journal of Computational Mathematics 2024年第2期42卷 337-354页

作者： Wansheng wang Department of Mathematics Shanghai Normal UniversityShanghai 200234China

Stability and global error bounds are studied for a class of stepsize-dependent linear multistep methods for nonlinear evolution equations governed by ω-dissipative vector fields in Banach *** break through the order barrier p≤1 of unconditionally contractive linear multistep methods for dissipative systems,strongly dissipative systems are *** employing the error growth function of the methods,new contractivity and convergence results of stepsize-dependent linear multistep methods on infinite integration intervals are provided for strictly dissipative systems(ω<0)and strongly dissipative *** applications of the main results to several linear multistep methods,including the trapezoidal rule,are *** theoretical results are also illustrated by a set of numerical experiments.

关键词： Nonlinear evolution equation Linear multistep methods ω-dissipative operators Stability Convergence Banach space

On Existence of the Even L_(p)Gaussian Minkowski Problem for p>n

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 179-192页

作者： Hejun wang School of Mathematics and Statistics Shandong Normal UniversityJi'nan 250014China

This paper concerns the even L_(p)Gaussian Minkowski problem in n-dimensional Euclidean space R^(n).The existence of the solution to the even L_(p)Guassian Minkowski problem for p>n is obtained.

关键词： Convex body Existence L_(p)Gaussian surface area measure The even L_(p)Gaussian Minkowski problem

Numerical three-dimensional modeling of earthen dam piping failure

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Water Science and Engineering 2024年第1期17卷 72-82页

作者： Zhengang wang Independent Researcher HerndonVA 20171USA

A physically-based numerical three-dimensional earthen dam piping failure model is developed for homogeneous and zoned soil *** model is an erosion model,coupled with force/moment equilibrium *** flow and two-dimensional(2D)shallow water equations(SWE)are solved to simulate dam break flows at different breaching *** rates of different soils with different construction compaction efforts are calculated using corresponding erosion *** dam's real shape,soil properties,and surrounding area are *** outer 2D-SWE grids are used to control upstream and downstream hydraulic conditions and control the boundary conditions of orifice flow,and inner 2D-SWE flow is used to scour soil and perform force/moment equilibrium *** model is validated using the European Commission IMPACT(Investigation of Extreme Flood Processes and Uncertainty)Test#5 in Norway,Teton Dam failure in Idaho,USA,and Quail Creek Dike failure in Utah,*** calculated peak outflows are within 10%errors of observed *** results show that,for a V-shaped dam like Teton Dam,a piping breach location at the abutment tends to result in a smaller peak breach outflow than the piping breach location at the dam's center;and if Teton Dam had broken from its center for internal erosion,a peak outflow of 117851 m'/s,which is 81%larger than the peak outflow of 65120 m3/s released from its right abutment,would have been released from Teton Dam.A lower piping inlet elevation tends to cause a faster/earlier piping breach than a higher piping inlet elevation.

关键词： 3D dam breach model 2D shallow water equations 3D slope stability analysis Piping failure Teton Dam Quail Creek Dike

含氟长链SiO_(2)纳米小球构筑聚芳醚酮超疏水薄膜材料及其性能研究

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化工新型材料 2022年第2期50卷 110-113,118页

作者：刘毛林王永鹏刘梦竹张赢元吉林化工学院材料科学与工程学院吉林132022

超疏水材料因其在防腐、防覆冰、自清洁以及油水分离等领域的广泛应用前景而受到越来越多的关注,发现了一种耐磨超疏水涂层的简易制备方法。该超疏水涂层以含有三氟甲基侧基的聚芳醚酮为主要构筑材料,通过喷涂含氟长链的SiO_(2)纳米小球... 详细信息

超疏水材料因其在防腐、防覆冰、自清洁以及油水分离等领域的广泛应用前景而受到越来越多的关注,发现了一种耐磨超疏水涂层的简易制备方法。该超疏水涂层以含有三氟甲基侧基的聚芳醚酮为主要构筑材料,通过喷涂含氟长链的SiO_(2)纳米小球(F-SiO_(2)纳米小球,尺寸480nm左右)、二氯甲烷溶胀和高温处理在涂层表面构筑微纳复合结构。这些微纳复合结构减少了水和涂层的接触面积,降低了水和涂层之间的附着力,因而使水滴在涂层上的接触角由92°增大到156°,涂层由疏水变为超疏水。此外由于含有三氟甲基侧基的聚芳醚酮的分子链与F-SiO_(2)纳米小球疏水链的相互缠结作用,所获得的超疏水薄膜具有良好的耐磨性能。经过砂纸打磨5次后,水在涂层上的接触角仍然高达143°。这种耐磨超疏水材料具有较高的使用寿命和广泛的实用价值。

关键词：聚芳醚酮超疏水含氟二氧化硅纳米小球薄膜

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离散智能制造模式下柔性装夹关键技术研究

制造技术与机床 2023年第4期 28-35页

作者：李瑞王永鹏南博儒杨恒李松涛航空工业庆安集团有限公司陕西西安710077

随着离散制造业智能制造的发展,柔性化、精密化和模块化的装夹技术在自动化加工过程中就显得尤为重要。为实现多品种、小批量、变状态的混线生产的自动化、智能化的精密加工,文章描述了零点定位技术在离散智能制造模型下的使用场景,并... 详细信息

随着离散制造业智能制造的发展,柔性化、精密化和模块化的装夹技术在自动化加工过程中就显得尤为重要。为实现多品种、小批量、变状态的混线生产的自动化、智能化的精密加工,文章描述了零点定位技术在离散智能制造模型下的使用场景,并重点从一面两销零点定位技术、锥自定心的零点定位技术,以及模块化装夹技术的原理、数学模型、误差分析、托盘的设计原则、装夹特点、受力分析和机外预调公差范围等方面进行了研究和分析,为离散智能制造模式下的精密自动化加工的装夹关键技术奠定了技术基础,并且对离散智能制造的推进具有一定的指导意义。

关键词：离散智能制造零点定位技术模块化装夹技术高精度误差分析

Predict the spatiotemporal distribution of solar magnetic field and understand the evolutionary feature of solar activity

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Science China Earth Sciences 2024年第8期67卷 2702-2704页

作者： Jingxiu wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

Solar activities are closely related to human production and daily *** warm sunlight nurtures life on Earth,but the Sun also occasionally exhibits eruptive activities that significantly impact and threaten the Earth’s *** eruptive activities occur as large-scale energy release processes in localized regions of the solar atmosphere,primarily manifested through the enhanced electromagnetic radiation and energetic particle emissions in solar flares,as well as the ejection of mass and magnetic flux in coronal mass ejections(CMEs).

关键词： Solar Earth evolutionary

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Effect of interplanetary magnetic field B_(x)on the polar electrojets as observed by CHAMP and Swarm satellites

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Earth and Planetary Physics 2024年第2期8卷 382-390页

作者： Hui wang ChengZhi wang YunFang Zhong Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

Based on 16 years of magnetic field observations from CHAMP and Swarm satellites,this study investigates the influence of the Interplanetary Magnetic Field(IMF)Bx component on the location and peak current density of the polar electrojets(PEJs).We find that the IMF Bx displays obvious local time,seasonal,and hemispherical effects on the PEJs,as follows:(1)Compared to other local times,its influence is weakest at dawn and dusk.(2)In the midnight sectors of both hemispheres,the IMF Bx tends to amplify the westward PEJ when it is0 in the Southern Hemisphere;this effect is relatively stronger in the local winter hemisphere.(3)At noontime,the IMF Bx intensifies the eastward current when it is0,it reduces the westward current;this effect is notably more prominent in the local summer hemisphere.(4)Moreover,the noontime eastward current shifts towards higher latitudes,while the midnight westward current migrates towards lower latitudes when IMF Bx is0 in the Southern Hemisphere.

关键词： polar electrojet interplanetary magnetic field Bx local time asymmetry hemispheric difference