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探究不同类型饮水对小鼠生长和粪便菌群的影响

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中国比较医学杂志 2024年第1期34卷 88-95页

作者：吴旭颖陈敏田玉书李斌张文明刘云波北京华阜康生物科技股份有限公司北京102200

目的探讨不同类型饮水对小鼠的生长和粪便菌群的影响。方法选取SPF级NIH小鼠,分成5组,每组32只,雌雄各半,分别饲喂纯净水(对照组)、酸化水、碱化水、弱酸水和固体水,连续监测20 d饮食和体重,实验结束后取动物粪便样本,用细菌16S rDNA通... 详细信息

目的探讨不同类型饮水对小鼠的生长和粪便菌群的影响。方法选取SPF级NIH小鼠,分成5组,每组32只,雌雄各半,分别饲喂纯净水(对照组)、酸化水、碱化水、弱酸水和固体水,连续监测20 d饮食和体重,实验结束后取动物粪便样本,用细菌16S rDNA通用引物扩增V3-V4区域,采用Illumina Miseq高通量测序平台进行测序,使用生物信息学方法进行微生物群落分析、α多样性分析和β多样性分析。结果在体重方面,不同pH的饮水,雌性小鼠中弱酸水组高于对照组,其他组均低于对照组(P>0.05);雄性小鼠中仅酸化水组的体重高于对照组,其他组均低于对照组,但组间无统计学差异(P>0.05);固体形态水的雌性和雄性小鼠的体重均低于对照组的体重(P<0.05)。在采食和饮水量方面,碱化水组的雌性小鼠饮水和采食量低于其他组,固体水组的饮水量,雌性和雄性小鼠均低于其他组。经OTU聚类分析,稀释性曲线说明本次测序的数据量合理。NIH小鼠粪便菌群共分成五个门,其中拟杆菌门和厚壁菌门占主要地位,属水平上主要是Unclassified Porphyromonadaceae、乳酸杆菌属和另枝菌属。5种类型饮水的粪便菌群丰度和多样性存在差异,α分析结果显示,在菌群的丰度和多样性上,酸化水组最高,而在菌群的多样性上,固体水组最低。β分析结果显示,固体水组和对照组的粪便菌群最接近,其次分别为碱化水组、酸化水组和弱酸水组。结论通过对不同类型饮水的探索,揭示了固体形态饮水方式对小鼠体重、采食量、饮水量和粪便菌群影响较大,而不同pH的饮水影响小鼠的粪便菌群丰度和多样性,尤其是酸化水对小鼠粪便菌群的影响更大。

关键词： pH 饮水高通量测序粪便菌群

Enhanced galloping energy harvester with cooperative mode of vibration and collision

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Applied Mathematics and Mechanics(English Edition) 2022年第7期43卷 945-958页

作者： Qiong WANG Zewen CHEN Linchuan ZHAO Meng LI Hongxiang ZOU Kexiang WEI Xizheng zhang wenming zhang Hunan Provincial Key Laboratory of Vehicle Power and Transmission System Hunan Institute of EngineeringXiangtan 411104Hunan ProvinceChina State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The low power and narrow speed range remain bottlenecks that constrain the application of small-scale wind energy *** paper proposes a simple,lowcost,and reliable method to address these critical issues.A galloping energy harvester with the cooperative mode of vibration and collision(GEH-VC)is presented.A pair of curved boundaries attached with functional materials are introduced,which not only improve the performance of the vibration energy harvesting system,but also convert more mechanical energy into electrical energy during *** beam deforms and the piezoelectric energy harvester(PEH)generates electricity during the flow-induced *** addition,the beam contacts and separates from the boundaries,and the triboelectric nanogenerator(TENG)generates electricity during the *** order to reduce the influence of the boundaries on the aerodynamic performance and the feasibility of increasing the working area of the TENG,a vertical structure is *** the wind speed is high,the curved boundaries maintain a stable amplitude of the vibration system and increase the frequency of the vibration system,thereby avoiding damage to the piezoelectric sheet and improving the electromechanical conversion efficiency,and the TENG works with the PEH to generate *** the boundaries can protect the PEH at high wind speeds,its stiffness can be designed to be low to start working at low wind *** electromechanical coupling dynamic model is established according to the GEH-VC operating principle and is verified *** results show that the GEH-VC has a wide range of operating wind speeds,and the average power can be increased by 180%compared with the traditional galloping *** GEH-VC prototype is demonstrated to power a commercial temperature *** study provides a novel perspective on the design of hybrid electromechanical conversion mechanisms,that is,to combine and collaborate based on their respective char

关键词： energy harvesting wind energy galloping piezoelectric energy harvester(PEH)

Existence and asymptotics of normalized solutions for the logarithmic Schrödinger system

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Science China Mathematics 2024年第9期67卷 2019-2048页

作者： Qian zhang wenming Zou Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

This paper is concerned with the following logarithmic Schrodinger system:{-Δu_(1)+ω_(1)u_(1)=u_(1)u_(1)logu_(1)^(2)+2p/p+q|u_(2)|^(q)|u_(1)|^(p-2)u_(1),-Δu_(2)+ω_(2)u_(2)=u_(2)u_(2)log u_(2)^(2)+2q/p+q|u_(1)|^(p)|u_(2)|^(q-2)u_(2),∫_(Ω)|u_(i)|^(2)dx=ρ_(i),i=1,2,(u_(1),u_(2))∈H_(0)^(1)(Ω;R^(2)),where Ω=R^(N)or Ω■R^(N)(N≥3)is a bounded smooth domain,andω_(i)R,μ_(i),ρ_(i)>0 for i=1,***,p,q≥1,and 2≤p+q≤2^(*),where 2^(*):=2N/*** using a Gagliardo-Nirenberg inequality and a careful estimation of u log u^(2),firstly,we provide a unified proof of the existence of the normalized ground state solution for all 2≤p+q≤2^(*).Secondly,we consider the stability of normalized ground state ***,we analyze the behavior of solutions for the Sobolev-subcritical case and pass to the limit as the exponent p+q approaches 2^(*).Notably,the uncertainty of the sign of u log u^(2)in(0,+∞)is one of the difficulties of this paper,and also one of the motivations we are interested *** particular,we can establish the existence of positive normalized ground state solutions for the Brézis-Nirenberg type problem with logarithmic perturbations(i.e.,p+q=2^(*)).In addition,our study includes proving the existence of solutions to the logarithmic type Bréis-Nirenberg problem with and without the L^(2)-*** ∫_(Ω)|u_(i)|^(2)dx=ρ_(i)(i=1,2)by two different methods,*** results seem to be the first result of the normalized solution of the coupled nonlinear Schrodinger system with logarithmic perturbations.

关键词： logarithmic Schrodinger system Brézis-Nirenberg problem normalized solution existence and stability behavior of solutions

Three-Dimensional Hierarchical Ternary Nanostructures Bismuth/Polypyrrole/CNTs for High Performance Potassium-lon Battery Anodes

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Chinese Journal of Chemistry 2022年第13期40卷 1585-1591页

作者： wenming zhang Xiaoyu Chen Haoshan Xu Yiqun Liu Xiaohui Zhao Zisheng zhang Ling Li National-Local Joint Engineering Laboratory of New Energy Photoelectric Devices College of Physics Science and TechnologyHebei UniversityBaodingHebei 071002China

In recent years,the anode materials of bismuth(Bi)-based potassium ion batteries with high theoretical capacity and suitable potassium ion insertion potential have attracted extensive ***,due to the volume expansion of Bi,the performance of Bi-based anode materials is not ideal during potassium ion(de)*** order to solve these problems,we report a three-dimensional(3D)ternary bismuth nanoparticles/conductive polymers/carbon nanotubes(Bi/PPy/CNT)hybrid anode material for K-ion *** a current density of 100 mA·g^(-1),its reversible capacity reaches 302 mAh·g^(-1) after 200 cycles,while it reaches 195.7 mAh·g^(-1) after 600 cycles at 1 A·g^(-1).Its excellent performance is attributed to the hydrogel network which provides a range of electron transport networks and high *** nanotubes are used as electron enhancers to reduce the volume expansion of Bi particles during the *** study provides a prerequisite for expanding the application of 3D ternary materials.

关键词： Bismuth Nanostructures Conducting materials Potassium ion battery Energy storage

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改进A^(*)算法的校园无人配送路径规划

包装工程 2024年第19期45卷 275-282页

作者：张文明吴岳忠文亚刘富民谭筠邓彬湖南工业大学轨道交通学院湖南株洲412007 湖南工业大学计算机学院湖南株洲412007 湖南工业大学期刊社湖南株洲412007 长沙行深智能科技有限公司长沙410000

目的以校园为应用场景,针对A^(*)算法规划的路径存在搜索效率低、拐角大且不符合校园无人配送车的运行约束条件等问题,提出一种基于A^(*)算法改进的高效路径搜索算法。方法首先通过改进评价函数的具体计算方式并为预估函数部分附加一个... 详细信息

目的以校园为应用场景,针对A^(*)算法规划的路径存在搜索效率低、拐角大且不符合校园无人配送车的运行约束条件等问题,提出一种基于A^(*)算法改进的高效路径搜索算法。方法首先通过改进评价函数的具体计算方式并为预估函数部分附加一个权重系数来减少不必要的往返搜索,以提高搜索速度;然后计算向量角和作线段来剔除冗余节点,以减小路径总长度;接着对OPEN表的数据存储结构进行替换,使用最小堆替换数组以更快访问最优节点,提升算法计算效率;最后采用贝塞尔曲线对路径进行平滑处理,使带尖角的地方变平滑,减小拐角。结果通过实验结果可知,改进后的A^(*)算法相比于传统A^(*)算法的搜索效率提高了58%,路径平滑程度也有显著提高。结论改进后的A^(*)算法可以用于校园无人车的路径规划,验证了算法的可行性。

关键词：路径规划 A^(*)算法评价函数贝塞尔曲线校园无人配送

面向太空垃圾捕获的自生长柔性变刚度机械臂设计与控制策略研究

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中国科学：物理学、力学、天文学 2024年第6期54卷 90-101页

作者：房付熠李汶柏魏星宇王叙宁吴志渊易志然张文明上海交通大学机械与动力工程学院上海200240 同济大学航空航天与力学学院上海200092

随着人类探索宇宙步伐的不断加速,太空轨道垃圾已成为一个重大的安全隐患.现有的刚性机械臂、飞网等捕获方式对不同距离、不同尺寸轨道垃圾的适应性有限,缺少一种能够应对各类轨道垃圾的捕获装置和捕获策略.针对这一问题,本文利用曲壳... 详细信息

随着人类探索宇宙步伐的不断加速,太空轨道垃圾已成为一个重大的安全隐患.现有的刚性机械臂、飞网等捕获方式对不同距离、不同尺寸轨道垃圾的适应性有限,缺少一种能够应对各类轨道垃圾的捕获装置和捕获策略.针对这一问题,本文利用曲壳梁可变刚度的特性,设计了一种新型的空间自生长柔性变刚度机械臂,实现了机械臂工作距离的大范围可调性;在此基础上,本文对这种新型的机械臂进行了动力学分析,提出了针对机械臂臂长分配的等矩原则,并建立了相应的算法;进一步的,本文面向跨尺寸的太空垃圾捕获,分别提出了抓取策略和缠绕策略,并采用取样避障和样条曲线方法,对机械臂进行了轨迹规划;最后,本文对所提出的针对自生长柔性变刚度机械臂的控制方法进行了仿真,验证了其可行性.

关键词：太空垃圾机械臂设计控制策略仿真验证

CMK-3 modified separator for ultra-high stability performance Cu_(1.8)Se aluminum batteries

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Nano Research 2022年第9期15卷 8136-8145页

作者： Xiaoxiao Li Mingxiao Ma Wenrong Lv Gaohong Wu Ruqian Lian wenming zhang Zhanyu Li Hebei Key Laboratory of Optic-Electronic Information and Materials National&Local Joint Engineering Laboratory of New Energy Photoelectric DevicesCollege of Physics Science and TechnologyHebei UniversityBaoding 071002China

Rechargeable aluminum batteries(RABs)are a popular energy storage device because of its safety and environmental *** cathode materials of RABs,transition metal oxide,sulfide,and selenide have become the research *** this work,we have successfully prepared CuO,Cu_(1.8)S,and Cu_(1.8)Se electrode *** them,although Cu_(1.8)Se had a relatively higher initial discharge capacity,all of these products had severe capacity degradation in terms of cycling and rate ***,for solving the problem of capacity decline,CMK-3 modified separator was used to make the Cu_(1.8)Se cathode material more stable,thus improving cycling and rate *** can be confirmed by ex situ X-ray photoelectron spectroscopy(XPS)that both Cu and Se elements underwent reversible redox reactions during the charging/discharging *** functional theory was implemented to study the energy storage mechanism of CumX(X=O,S,Se).The results showed that Cu_(1.8)S and Cu_(1.8)Se mainly relied on AlCl4−for energy storage,and the intercalation/de-intercalation of Al3+occurred during the charge/discharge process in CuO ***,the optimized Cu_(1.8)Se/CMK-3@GF/C/Al revealed an outstanding rate capability(977.83 mAh·g^(−1)at 0.5 A·g^(−1))and long cyclic stability(retention of 478.77 mAh·g^(−1)after 500 cycles at 1.0 A·g^(−1)).Compared to previously reported cathode materials of RABs,this type of battery displays great superiority in terms of rate and cycling *** research also provides a novel approach to suppress the shuttle effect of active species for advanced clean energy devices.

关键词： rechargeable aluminum batteries Cu_(1.8)Se CMK-3 modified density functional theory long cyclic stability

Enhancing the activity of FeNi bimetallic electrocatalysts on overall water splitting by Nd_(2)O_(3)-induced FeNi lattice contraction

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Journal of Energy Chemistry 2023年第12期87卷 42-50,I0003页

作者： Jiajia Li Yunong Qin Tianyu Tan Qiancheng Zhu Bo Ouyang Erjun Kan wenming zhang Province-Ministry Co-construction Collaborative Innovation Center of Hebei Photovoltaic Technology College of Physics Science and TechnologyHebei UniversityBaoding 071002HebeiChina MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing Nanjing University of Science and TechnologyNanjing 210094JiangsuChina

The development of high-efficiency and cost-effective bifunctional electrocatalysts for overall water splitting remains a formidable ***,FeNi-Nd_(2)O_(3) nanoparticles anchored on N-doped carbon nanotubes(FeNi-Nd_(2)O_(3)/NCN) are designed for highly effective overall water splitting via a facile two-step hydrothermal *** synthetic FeNi-Nd_(2)O_(3) hetero-trimers(Fe 2p-Ni 2p-Nd 3d orbital coupling)on NCN achieve excellent oxygen evolution reaction(OER) and hydrogen evolution reaction(HER) activities with overpotentials of 270 and 120 mV at 10 mA cm^(-2) in 1 M KOH ***,a small voltage of 1.52 V at 10 mA cm^(-2) is achieved when FeNi-Nd_(2)O_(3)/NCN is assessed as bifunctional catalyst for overall water splitting,which is superior to the typically integrated Pt/C and RuO_(2) counterparts(1.54 V at 10 mA cm^(-2)).The related characterizations including X-ray absorption fine structure(XAFS)spectroscopy show that the remarkably improved activity is originated from Nd_(2)O_(3)-induced FeNi bimetallic lattice ***,density functional theory(DFT) calculations indicate that the lattice contraction reduces binding energies of intermediates by downshifting the position of FeNi bimetallic d-band center relative to the Fermi level to optimize catalytic ***,the Nd_(2)O_(3)-induced FeNi bimetallic lattice contraction may provide a new perspective for designing and synthesizing innovative catalytic systems.

关键词： Bifunctional catalyst FeNi-Nd_(2)O_(3)hetero-trimers Lattice contraction Overall water splitting

Magnetic levitation using diamagnetism:Mechanism,applications and prospects

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Science China(Technological Sciences) 2021年第1期64卷 44-58页

作者： GAO QiuHua YAN Han ZOU HongXiang LI WenBo PENG ZhiKe MENG Guang zhang wenming State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

As a typical contact-free manipulation technique that removes friction and contamination risk,levitation has gradually become a preferred candidate for various *** levitation using diamagnetism,beyond Earnshaw’s theorem,is a kind of passive stable levitation that can be achieved at normal temperatures with no energy ***,most seemingly nonmagnetic materials can be levitated in a magnetic field and can stabilize free levitation of magnetic *** review focuses on the fundamental principles of magnetic levitation using diamagnetism,with emphasis on its burgeoning *** theoretical basis associated with the magnetic levitation using diamagnetism is discussed by elucidating the characteristics of diamagnetic materials,and the key levitation mechanisms are ***,state-of-the-art applications in various aspects,including sensing and measurement,actuating and micromanipulation,energy harvesting and magnetic gravity compensation,are summarized and ***,the review concludes with a brief outlook on future perspectives.

关键词： magnetic levitation diamagnetism sensors actuators energy harvesters