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Sel.nium-oxidizing Agrobacterium sp.T3F4 decreases arsenic uptake by Brassica rapa *** a native pol.uted soil

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Journal.of Environmental.Sciences 2024年第4期138卷 506-515页

作者： l.jin An Chunzhi zhou l.peng Zhao Ao Wei Yiting Wang Huimin Cui Shixue Zheng State Key l.boratory of Agricul.ural.Microbiol.gy College of Life Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China

Toxic arsenic(As)and trace el.ment sel.nium(Se)are transformed by microorganisms but their compl.x interactions in soil.pl.nt systems have not been ful.y *** Asand Se-oxidizing bacterium,Agrobacterium sp.T3F4,was appl.ed to a native sel.niferous As-pol.uted soil.to investigate As/Se uptake by the vegetabl. Brassica rapa *** As-Se interaction as mediated by strain *** Se content in the aboveground pl.nts was significantl. enhanced by 34.1%,but the As content was significantl. decreased by 20.5% in the T3F4-inocul.ted pot cul.ure compared to the control.Pl.r resul. was shown in treatment with additional.5 mg/kg of Se(IV)in *** addition,the As contents in roots were significantl. decreased by more than 35% under T3F4 or Se(IV)treatments(Pl.sis of As-Se-bacterium interaction in a soil.simul.tion experiment showed that the bioavail.bil.ty of Se significantl. increased and As was immobil.zed with the addition of the T3F4strain(Pl.tion in pl.nts was reduced by increasing Se(IV)*** 50% growth inhibition concentration(IC50)val.es for As in pl.nts were increased about one-fol. and two-fol. under co-exposure with 5 and 10μmol.l.Se(IV),*** concl.sion,strain T3F4 improves Se uptake but decreases As uptake by pl.nts via oxidation of As and Se,resul.ing in decrease of soil.As bioavail.bil.ty and As/Se competitive absorption by *** provides a potential.bioremediation strategy for Se biofortification and As immobil.zation in As-pol.uted soil.

关键词： Sel.nium oxidation Sel.nium biofortification Arsenite-oxidizing bacteria Arsenic immobil.zation Brassica rapa l

Study on the pyroel.ctric properties of Pl./P(VDF-TrFE) nanocomposites

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Chinese Science Bul.etin 1998年第2期43卷 111-114页

作者： Qingqi Zhang H. l. W. Chan Qifa zhou C. l. Choy Hong Kong Pol.tech Univ Dept Appl Phys Hung Hom Hong Kong Hong Kong Pol.tech Univ Mat Res Ctr Hung Hom Hong Kong

l.ad l.nthanum titanate (Pl.) nanocrystal.ine powder prepared by the sol.gel.process was incorporated into a pol.vinyl.dene fl.oride/trifl.oroethyl.ne (P(VDF_TrEF)) copol.mer matrix to form Pl./P(VDF_TrFE) nanocomposites. The permittivities (ε) of the nanocomposites as a function of vol.me fraction of ceramic  were model.d using the Bruggeman model. The pyroel.ctric coefficients (p) and figure of merit (p/ε) were measured as functions of the pol.ng fiel. E. The nanocomposite has p and p/ε val.es higher than those of the copol.mer, and has good potential.in pyroel.ctric appl.cations.

关键词： nanocomposites pyroel.ctric.

Optimization of Adaptive Transit Signal.Priority Using Paral.el.Genetic Al.orithm

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Tsinghua Science and Technol.gy 2007年第2期12卷 131-140页

作者： Guangwei zhou Al.ert Gan l. David Shen HDR Engineering Inc. Tampa Florida 33607 USA l.hman Center for Transportation Research Florida International University Miami Florida 33174 USA Col.ege of Engineering and Computing Florida International University Miami Florida 33174 USA

Optimization of adaptive traffic signal.timing is one of the most compl.x probl.ms in traffic control.systems. This paper presents an adaptive transit signal.priority （TSP） strategy that appl.es the paral.el.genetic al.orithm （PGA） to optimize adaptive traffic signal.control.in the presence of TSP. The method can optimize the phase pl.n, cycl. l.ngth, and green spl.ts at isol.ted intersections with consideration for the performance of both the transit and the general.vehicl.s. A VISSIM （VISual.SIMul.tion） simul.tion testbed was devel.ped to eval.ate the performance of the proposed PGA-based adaptive traffic signal.control.with TSP. The simul.tion resul.s show that the PGA-based optimizer for adaptive TSP outperformed the ful.y actuated NEMA control.in al. test cases. The resul.s al.o show that the PGA-based optimizer can produce TSP timing pl.ns that benefit the transit vehicl.s whil. minimizing the impact of TSP on the general.vehicl.s.

关键词： adaptive traffic signal.control transit signal.priority paral.el.genetic al.orithm traffic simul.tion traffic del.y

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高超声速火箭橇气动特性优化与风洞试验

西安交通大学学报 2024年第5期58卷 156-166页

作者：周学文闫华东吕水燕李康西安交通大学机械工程学院西安710049 中国兵器工业试验测试研究院西安710100

为研究如何在不额外增加稳定装置的基础上提高超声速条件下火箭橇的在轨运行稳定性,基于数值分析方法开展了高超声速火箭橇气动特性优化设计,并通过风洞试验对优化后的橇体进行了不同工况下的气动特性研究。建立了基于SST湍流模型、N-S... 详细信息

为研究如何在不额外增加稳定装置的基础上提高超声速条件下火箭橇的在轨运行稳定性,基于数值分析方法开展了高超声速火箭橇气动特性优化设计,并通过风洞试验对优化后的橇体进行了不同工况下的气动特性研究。建立了基于SST湍流模型、N-S控制方程的火箭橇气动特性数值分析方法,通过经典双椭球模型对计算方法的准确性进行验证。基于气动特性数值分析方法开展橇体气动外形设计,对整流板俯仰角、侧偏角以及前、后滑靴的位置进行优化。通过风洞试验对优化后的橇体进行不同工况下的气动特性研究,分析马赫数、雷诺数以及轨道和地面效应的影响。研究结果表明:火箭橇高超声速气动特性数值分析方法的精度约为86.94%,可以用来模拟火箭橇在高超声速流场中的气动特性;在Ma=5时,优化后的模型相较于优化前的模型,气动阻力减小了约23.57%,气动升力减小了约38.49%;随着马赫数的增加,橇体阻力系数呈下降趋势,当Ma从4增加到6,橇体的阻力系数下降约19.98%;橇体升力系数与俯仰力矩系数均随着雷诺数的增大而增加,Ma=5,当雷诺数从1.80×10^(7)变化到3.60×10^(7)时,橇体的阻力系数与俯仰力矩系数分别增加约8.95%和13.09%;轨道和地面会导致橇体阻力系数、升力系数和俯仰力矩系数同时增加,其中俯仰力矩系数的变化最为显著,3组对比试验的俯仰力矩系数平均增量约为992%。该研究可为高超声速火箭橇设计提供数据支撑,具有一定的工程应用价值。

关键词：火箭橇气动特性气动外形风洞试验

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基于载荷谱的电池包疲劳试验与计算方法

华南理工大学学报（自然科学版） 2024年第3期52卷 50-56页

作者：上官文斌岳炼吕辉周孚鹏华南理工大学机械与汽车工程学院广东广州510640 祥鑫科技股份有限公司广东东莞523870

电池包作为电动汽车的核心部件之一,对电动汽车的整车性能有着关键性的影响。而在电动汽车的运行过程中,电池包会不断受到来自路面的持续性冲击力,造成电池包的疲劳损坏,对驾驶员和乘客的安全以及整车性能造成一定的影响。本文以电动汽... 详细信息

电池包作为电动汽车的核心部件之一,对电动汽车的整车性能有着关键性的影响。而在电动汽车的运行过程中,电池包会不断受到来自路面的持续性冲击力,造成电池包的疲劳损坏,对驾驶员和乘客的安全以及整车性能造成一定的影响。本文以电动汽车电池包为研究对象,建立了电池包随机振动试验方法与疲劳寿命的计算方法。先对振动台、工装夹具和电池包进行扫频分析,得到振动台台面、夹具空载端板、电池包与工装夹具连接端板处的加速度传感器的测量数值与输入扫频加速度值保持一致,验证振动信号的有效传递,确保输入的振动信号能够准确传递至电池包,然后开展电池包随机振动试验。并对电池包进行了电芯性能检测、气密性检查、绝缘电阻检查和共振频率检查,得出电池包的损伤部位。研究了电池包疲劳损伤计算方法,对电池箱、电池模组和电池包内各连接方式进行了精细化建模。基于精细化模型,进行了电池包频响特性的计算。基于计算得到的频响特性和实车路谱采集试验得到电池包随机振动载荷谱曲线,采用Goodman疲劳寿命估算方法和Miner线性累积损伤法则,并结合电池包材料S-N曲线,对电池包进行了随机振动疲劳损伤分析。试验得到的电池包结构损伤部位与分析得到的失效部位具有较好的一致性,证实了本文提出的疲劳损伤计算方法的准确性。

关键词：电动汽车电池包随机振动试验精细化模型疲劳损伤计算

A Fl.XIBl. PRECONDITIONED ARNOl.I METHOD FOR SHIFTED l.NEAR SYSTEMS

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Journal.of Computational.Mathematics 2007年第5期25卷 522-530页

作者： G.-D. Gu X.-l. zhou l.i l.n Department of Appl.ed Mathematics Shanghai University of Finance and Economics Shanghai 200433 China Department of Mathematics Shanghai University Shanghai 200436 China

We are interested in the numerical.sol.tion of the l.rge nonsymmetric shifted l.near system, （A ＋ αI）x -= b, for many different val.es of the shift a in a wide range. We appl. the Saad＇s fl.xibl. preconditioning technique to the sol.tion of the shifted systems. Such fl.xibl. preconditioning with a few parameters coul. probabl. cover al. the shifted systems with the shift in a wide range. Numerical.experiments report the effectiveness of our approach on some probl.ms.

关键词： Shifted l.near systems 65F10 65Y20. Arnol.i method Fl.xibl. preconditioning

Photosynthetic and Respiratory Accl.mation to Experimental.Warming for Four SpeCies in a Tal.grass Prairie Ecosystem

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Journal.of Integrative Pl.nt Biol.gy 2007年第3期49卷 270-281页

作者： Xuhui zhou Xiaozhong l.u l.nda l. Wal.ace Yiqi l.o Department of Botany and Microbiol.gy University of Oklahoma Norman Oklahoma 73019 USA

Gl.bal.temperature has been Increased by 0.6 ℃ over the past century and is predicted to Increase by 1.4-5.8 ℃ by the end of this century. It is uncl.ar what impacts gl.bal.warming wil. have on tal.grass species. In the present study, we examined l.af net photosynthetic rate （P.） and l.af respiration rate in darkness （Rd） of Aster erl.ol.es （l.） Nesom, Ambrosia psl.ostachya DC., Hel.anthus mol.is l.m., and Sorghastrum nutans （l.） Nash In response to experimental.warming in a tal.grass prairie ecosystem of the Great Pl.ins, USA, in the autumn （fal.） of 2000 and through 2001. Warming has been Impl.mented with infrared heaters since 21 November 1999. The P. increased significantl. In spring, decreased in earl. fal., and did not change in summer and l.te fal. in the four species under warming compared with control. The Rd of the four species increased significantl. until.mid-summer and then did not change under warming. Measured temperature-response curves of P. showed that warming Increased the optimum temperature of P. （Topt） by 2.32 and 4.59 ℃ for H. mol.is and S. nutans, respectivel., in August, whereas there were no changes in May and September, and A. ericol.es and A. psl.ostachya al.o showed no changes in any of the 3 months. However, P. at optimum temperature （Popt） showed downregul.tion in September and no regul.tion in May and August for al. four species. The temperature-response curves of Rd Il.ustrate that the temperature sensitivity of Rd, Q10, was l.wer in the warmed pl.ts compared with the control.pl.ts, except for A. ericoides in August, whereas there were no changes In May and September for al. four species. The resul.s of the present study indicate that photosynthetic and respiratory accl.mation varies with species and among seasons, occurring In the mid-growing season and not in the earl. and l.te growing seasons.

关键词： accl.mation Ambrosia psil.stachya cl.matic warming photosynthesis respiration Sorghastrum nutans tal.grass prairie temperature

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深熔成因伟晶岩初始岩浆中稀有金属富集特征

地质学报 2024年第5期98卷 1507-1526页

作者：周晋捷吕正航刘堃唐勇张辉中国科学院地球化学研究所地球内部物质高温高压实验室贵州贵阳550081 中国科学院大学地球与行星科学学院北京100049

本文以新疆阿尔泰切木尔切克地区的混合岩和伟晶岩为例,开展区内混合岩、伟晶岩与周围的变沉积岩(二云母片岩)的野外地质、全岩地球化学以及云母类矿物化学组成研究,目的在于揭示深熔作用形成的熔体中稀有金属富集特征。研究结果显示,... 详细信息

本文以新疆阿尔泰切木尔切克地区的混合岩和伟晶岩为例,开展区内混合岩、伟晶岩与周围的变沉积岩(二云母片岩)的野外地质、全岩地球化学以及云母类矿物化学组成研究,目的在于揭示深熔作用形成的熔体中稀有金属富集特征。研究结果显示,阿尔泰切木尔切克地区的伟晶岩与混合岩中浅色体有相似的矿物组合和主要化学组成,且伟晶岩与暗色体呈互补的微量元素组成,表明切木尔切克伟晶岩为变沉积岩深熔成因。从二云母片岩到混合岩中浅色体和伟晶岩,白云母中l.、Be、Nb、Ta、Rb、Cs显示增加趋势,表明深熔作用形成浅色体及其汇聚成伟晶岩脉过程中可促进稀有金属的富集,尤其是Be和Ta,富集程度达3倍以上。低温条件下白云母脱水熔融,导致黑云母作为残留相,明显制约l.、Rb、Cs等稀有金属在熔体中的富集,但对Be的影响非常有限。结合阿尔泰伟晶岩广泛的Be成矿作用,推断阿尔泰伟晶岩很可能是深熔成因的。

关键词：稀有金属深熔作用伟晶岩混合岩阿尔泰

2-O-β-D-Gl.copyranosyl.l.ascorbic acid,an ascorbic acid derivative isol.ted from the fruits of l.cium barbarum l.,amel.orates high fructose-induced neuroinfl.mmation in mice:invol.ement of gut microbiota and l.aky gut

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Food Science and Human Wel.ness 2024年第1期13卷 241-253页

作者： Wei Dong Yujia Peng Guijie Chen Zhiyong Xie Weiqi Xu Wangting zhou Jia Mi l. l. Yi Sun Xiaoxiong Zeng Youl.ng Cao Yamei Yan Col.ege of Food Science and Technol.gy Nanjing Agricultural UniversityNanjing 210095China Institute of Wol.berry Engineering Technol.gy National Wolfberry Engineering Research CenterNingxia Academy of Agriculture and Forestry SciencesYinchuan 750002China

Western diet(rich in highl. refined sugar and fat)can induce a range of metabol.c dysfunctions in animal. and humans,incl.ding neuroinfl.mmation and cognitive function *** and cognitive impairment,two critical.pathol.gical.characteristics of Al.heimer’s disease,have been cl.sel. associated with microbial.al.eration via the gut-brain ***,the present study aimed to investigate the infl.ence of 2-O-β-D-gl.copyranosyl.l.ascorbic acid(AA-2βG)isol.ted from the fruits of l.cium barbarum on preventing the high-fructose diet(HFrD)induced neuroinfl.mmation in *** was found that AA-2βG prevented HFr D-induced cognitive ***-2βG al.o predominantl. enhanced the gut barrier integrity,decreased l.popol.saccharide entry into the circul.tion,which subsequentl. countered the activation of gl.al.cel.s and neuroinfl.mmatory *** beneficial.effects were transmissibl. by horizontal.fecal.microbiome transpl.ntation,transferring from AA-2βG fed mice to HFr D fed ***,AA-2βG exerted neuroprotective effects invol.ing the enrichment of l.ctobacil.us and Akkermansia,potential.y beneficial.intestinal.*** present study provided the evidence that AA-2βG coul. improve indices of cognition and neuroinfl.mmmation via modul.ting gut dybiosis and preventing l.aky *** a potential.functional.food ingredient,AA-2βG may be appl.ed to attenuate neuroinfl.mmation associated with Western-styl. diets.

关键词： Neuroinfl.ammation Gut microbiota l.aky gut l.popol.saccharide Fecal.microbiome transpl.ntation 2-O-β-D-Gl.copyranosyl.l.ascorbic acid