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Nano Research 2024年第8期17卷 7013-7019页

作者： Haoran Wang Rongbo Sun Peigen Liu Haohui Hu Chen Ling Xiao Han Yi Shi Xusheng Zheng geng wu Xun Hong Center of Advanced Nanocatalysis(CAN) Department of Applied ChemistryHefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Sinochem Holdings Co Ltd Xiongan New AreaHebei 071700China National Synchrotron Radiation Laboratory(NSRL) University of Science and Technology of ChinaHefei 230029China

The electrochemical CO_(2) reduction reaction(CO_(2)RR)holds significant promise in advancing carbon *** catalysts for the electrochemical CO_(2)RR to multi-carbon(C_(2+))products(e.g.,C_(2)H_(4))under industrial-level current density is urgently needed and ***,we report the Cu_(2)O nanoparticles doped with interstitial carbon atoms(denoted as C-Cu_(2)O NPs)for the conversion of CO_(2) to C_(2+)*** interstitial carbon promotes the C-Cu_(2)O NPs to possess abundant unsaturated Cu–O bonds,leading to a high-density Cu^(δ+)(0<δ<1)*** obtained C-Cu_(2)O NPs exhibited significant Faradic efficiency(FE)of C_(2+) products approaching 76.9%and a partial current density reaching 615.2 mA·cm^(–2)under an industrial-level current density of 800 mA·cm^(–2).Furthermore,the efficient electrosynthesis of C_(2)H_(4) achieved an FE of 57.4%with a partial current density of 459.2 mA·cm^(–2).In situ electrochemical attenuated total reflection Fourier transform infrared spectroscopy and in situ Raman spectroscopy analyses revealed that C-Cu_(2)O NPs stabilized the intermediate*CO and facilitated C–C coupling,leading to increased selectivity towards C_(2+) products.

关键词： CO_(2) electroreduction C-C coupling interstitial carbon *CO coverage industrial-level current density

GeoChip-based microbial functions in biogeochemical cycles and their responses to environmental factors in Tengchong hot springs

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Journal of Earth Science 2024年

作者： Muhammad Inayat Ullah Khan Liuqin Huang geng wu Jian Yang Xiangyu Guan Hongchen Jiang School of Environmental Studies， China University of Geosciences School of Ocean Sciences， China University of Geosciences Beijing State Key Laboratory of Biogeology and Environmental Geology， China University of Geosciences

Microorganisms actively participate in biogeochemical cycling processes and play a crucial role in maintaining the dynamic balance of hot spring ecosystems. However， the distribution of microbial functional genes and their influencing factors in hot springs remain largely unclear. Therefore， this study investigated the microbial functional genes and their potential for controlling biogeochemical cycles (C， N， S， and P) in the hot Springs of Tengchong， China， using the Geochip method， a functional gene microarray technology. The examined hot springs have very different microbial functional genes. A total of 22736 gene probe signals were identified， belonging to 567 functional genes and associated with 15 ecological functions， mainly involving stress response， carbon cycle， nitrogen cycle， sulfur cycle， phosphorus cycle and energy processes. The amyA， narG， dsrA and ppx genes were most abundant in carbon， nitrogen， sulfur and phosphorus cycles， respectively， and were significantly correlated with pH， temperature and SO42-. The diversity and abundance of detected gene probes were negatively correlated with temperature. The α-diversity (i.e.， Shannon index) was high at low temperature and low pH. Molecular functional interactions revealed by the gene connectivity levels were negatively correlated with temperature， pH and SO42-. These results suggested that the abundance， diversity and interactions of microbial functional genes were significantly influenced by geochemical parameters?. In addition， some genera possessed functional genes related to carbon， nitrogen， sulfur， and phosphorus cycles and can synergistically control the biogeochemical cycles of carbon， nitrogen， sulfur and phosphorus. These findings provide new insights into the functional potentials of microorganisms to participate in biogeochemical cycles and their responses to environmental factors in hot springs.

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Stabilization of coordinated motion for underwater vehicles

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Acta Mechanica Sinica 2011年第3期27卷 438-444页

作者： Fan wu Zhi-Yong geng State Key Laboratory for Turbulence and Complex Systems Peking University 100871 Beijing China

This paper presents a coordinating and stabilizing control law for a group of underwater vehicles with unstable dynamics. The coordinating law is derived from a potential that only depends on the relative configuration of the underwater vehicles. Being coordinated,the group behaves like one mechanical system with symmetry,and we focus on stabilizing a family of coordinated motions,called relative equilibria. The stabilizing law is derived using energy shaping to stabilize the relative equilibria which involve each vehicle translating along its longest（unstable） axis without spinning,while maintaining a relative configuration within the group. The proposed control law is physically motivated and avoids the linearization or cancellation of nonlinearities.

关键词： Underwater vehicles . Coordination .Relativeequilibria. Stabilization. Energy shaping

Network boundary recognition via relative azimuth angle

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 31-41页

作者： JIA Rui-wu SHI geng-chen National Lab of Mechatronic Engineering and Control Beijing Institute of Technology Beijing 100081 China

To recognize the boundary of wireless networks to meet some specific needs, relative azimuth angles of nodes distributed in the 1-hop neighborhood of each node in one network were used to recognize the boundary of the network. A novel recognition algorithm based on local generalized convex hull was proposed for one node to decide if it self is a boundary node. The flexibility, efficiency and consistency of the algorithm are shown in its performance by extensive simulations.

关键词： wireless sensor network boundary point generalized convex hull relative azimuth angle θ-hull

NRG1基因修饰的骨髓基质干细胞移植对大鼠脊髓半横切损伤的修复作用及其机制

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解放军医学杂志 2024年第2期49卷 204-213页

作者：符禹玄陈君赵富生李媛媛张可心武庚牡丹江医学院第一临床医学院骨科黑龙江牡丹江157000 牡丹江医学院组织学与胚胎学教研室黑龙江牡丹江157000

目的探讨移植神经调节蛋白1(NRG1)基因修饰的骨髓基质干细胞(BMSCs)对大鼠脊髓半横切损伤(SCI)的修复作用及其可能机制。方法分离培养大鼠BMSCs,转染NRG1基因,采用ELISA法测定BMSCs裂解液和培养液上清中NRG1蛋白含量,细胞计数法检测BMSC... 详细信息

目的探讨移植神经调节蛋白1(NRG1)基因修饰的骨髓基质干细胞(BMSCs)对大鼠脊髓半横切损伤(SCI)的修复作用及其可能机制。方法分离培养大鼠BMSCs,转染NRG1基因,采用ELISA法测定BMSCs裂解液和培养液上清中NRG1蛋白含量,细胞计数法检测BMSCs增殖活性。43只健康8周龄SD大鼠,随机分为对照组(n=10)、SCI模型组(n=10)、BMSCs组(n=10)与NRG1-BMSCs组(n=13)。建立大鼠脊髓半横切损伤模型后,原位移植BMSCs和NRG1-BMSCs。移植第1、7、14、21、28天,采用BBB评分、斜板实验评估大鼠后肢运动功能;移植第7天,应用荧光显微镜观察移植细胞迁移及分布情况;移植第28天,采用HE染色和Nissl染色观察大鼠脊髓组织病理学变化,TUNEL染色检测脊髓组织细胞凋亡情况,Western blotting检测脊髓组织内质网应激相关蛋白[X-box结合蛋白1(XBP1)、C/EBP同源蛋白(CHOP)、转录激活因子4(ATF4)、ATF6和葡萄糖调节蛋白78(GRP78)]及凋亡相关蛋白[B淋巴细胞瘤-2蛋白(Bcl-2)、Bcl-2相关X蛋白(Bax)]的表达。结果成功分离培养BMSCs,并转染NRG1基因。ELISA法检测结果显示,NRG1-BMSCs裂解液和培养液上清中NRG1蛋白含量明显高于BMSCs,且呈时间依赖性(P<0.05)。NRG1-BMSCs增殖活性明显高于BMSCs(P<0.05)。移植第21、28天,NRG1-BMSCs组BBB评分及斜板倾斜角度均高于SCI模型组和BMSCs组(P<0.05),但未恢复到对照组水平(P<0.05)。移植第28天,与SCI模型组和BMSCs组比较,NRG1-BMSCs组大鼠脊髓组织神经元核固缩减少,尼氏体密度增加,XBP1、CHOP、ATF4、ATF6、GRP78、Bax蛋白表达水平及TUNEL阳性细胞率明显降低(P<0.05),Bcl-2蛋白表达水平明显升高(P<0.05)。结论移植NRG1基因修饰的BMSCs能够减轻SCI,促进大鼠运动功能恢复,其机制可能与增加BMSCs增殖活性、抑制脊髓组织细胞凋亡、减轻内质网应激反应有关。

关键词：脊髓半横切损伤神经调节蛋白1 骨髓基质干细胞内质网应激凋亡

干湿循环作用下高压实膨胀土及改性土裂隙演化规律及机理研究

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水利水电技术（中英文） 2024年第S1期55卷 370-377页

作者：吴庚于怀昌张中印梁艳坤王闯吕寒雪中国南水北调集团中线有限公司渠首分公司河南南阳473000 华北水利水电大学河南郑州450046

干湿循环作用下膨胀土裂隙发育是影响南水北调工程渠坡安全的主要因素之一。为研究不同干湿循环作用下高压实膨胀土及水泥改性土的裂隙演化规律及机理,分别对为20 mm和40 mm高度的渠坡膨胀土及水泥改性土的环刀试样进行了7次室内干湿循... 详细信息

干湿循环作用下膨胀土裂隙发育是影响南水北调工程渠坡安全的主要因素之一。为研究不同干湿循环作用下高压实膨胀土及水泥改性土的裂隙演化规律及机理,分别对为20 mm和40 mm高度的渠坡膨胀土及水泥改性土的环刀试样进行了7次室内干湿循环试验。试验结果表明:(1)随着干湿循环次数的增加,高压实膨胀土试样的最终裂隙率和分形维数不断增大并趋于稳定,达到一定的循环次数后,试样高度对裂隙率的影响减弱,而对分形维数的影响增大。(2)高压实水泥改性土在经历7次干湿循环后,试样表面没有出现裂隙,表明水泥可以有效的抑制膨胀土裂隙的发育。(3)在第2~3次干湿循环过程中,试样表面裂隙出现了自愈合现象。随着干湿循环次数的增加,膨胀土试样裂隙起裂时间提前,试样出现了不可逆转的损伤,自愈合现象消失。试样高度越高,试样裂隙的起裂时间越长。(4)由于高压实膨胀土团聚体失水收缩使得其空隙空间增加,加速了水分子的逃逸,导致高压实膨胀土和改性土的失水速率可分为3个阶段:加速率阶段、常速率阶段、减速率阶段。(5)在加速率和常速率阶段,试样高度对失水速率几乎没有影响。在减速率阶段,与40 mm高度试样相比,20 mm高度试样的失水速率降低的更快,进入减速率阶段的时间更早。随着干湿循环次数的增加,试样失水速率明显降低。

关键词：干湿循环高压实膨胀土改性土裂隙演化机理

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TC4钛合金电致塑性本构方程建立

塑性工程学报 2024年第3期31卷 91-99页

作者：翟瑞雪吴庚洋乔铮金卓翰李书宇张正义燕山大学先进锻压技术与科学重点实验室河北秦皇岛066004 燕山大学机械工程学院河北秦皇岛066004

采用自行设计的绝缘夹具对TC4钛合金板材进行了电致塑性单向拉伸试验。基于对照试验的方法,以无脉冲电流且不同温度条件作为参照,与同等温度条件下脉冲电流加热情况进行对比,以探索电流参数对TC4钛合金电致塑性效应和力学性能的影响规... 详细信息

采用自行设计的绝缘夹具对TC4钛合金板材进行了电致塑性单向拉伸试验。基于对照试验的方法,以无脉冲电流且不同温度条件作为参照,与同等温度条件下脉冲电流加热情况进行对比,以探索电流参数对TC4钛合金电致塑性效应和力学性能的影响规律。结果表明:在试验研究范围内,脉冲电流的占空比主要影响材料的温度变化,脉冲电流密度对TC4钛合金的电致塑性起主导地位,脉冲电流作用下的TC4钛合金材料抗拉强度大幅下降,塑性提高。基于Johnson-Cook模型和Arrhenius方程建立了耦合温度和脉冲电流密度的TC4钛合金电致塑性本构方程,并进行了验证。

关键词： TC4钛合金电致塑性效应本构方程应力-应变关系

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综合性医院实验室气体供应系统建设

医用气体工程 2024年第3期4卷 46-49页

作者：全穗海李慧媛吴耿中山大学附属第一医院广东广州510080

本文以中山大学附属第一医院生殖医学中心实验室气体供应系统建设为例,阐述实验室气体供应系统在设计、选材、安装各个环节所遵循的原则及实施过程中应注意的问题,总结经验和成效,并提出未来实验室气体供应系统建设方向。

关键词：生殖医学实验室气体供应系统原则

Imidacloprid-induced transference effect on some elements in rice plants and the brown planthopper Nilaparvata lugens （Hemiptera： Delphacidae）

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Insect Science 2011年第3期18卷 289-297页

作者： Samer Azzam Fan Yang Jin-Cai wu Jin geng Guo-Qing Yang School of Plant Protection Yangzhou University Yangzhou Jiangsu Province China

The widespread use ofimidacloprid against insect pests has not only increased the rate of the development of target pest resistance but has also resulted in various negative effects on rice plants and Nilaparvata lugens resurgence. However, the effect of imidacloprid on elements in rice plants and the transference of these element changes between rice and N. lugens are currently poorly understood. The present study investigated changes ofCu, Fe, Mn, Zn, Ca, K, Mg and Na contents in rice plants following imidacloprid foliar sprays in the adult female ofN./ugens that develops from nymphs that feed on treated plants and honeydew produced by females. The results indicated that imidacloprid foliar spray significantly increased Fe and K contents in leaf sheaths. Generally, Fe, Mn, K and Na contents in leaf blades were noticeably decreased, but Ca contents in leaf blades for ! 0 and 30 mg/kg imidacloprid treatments were significantly increased. The contents of most elements except K and Mg in the adult females and honeydew were significantly elevated. Multivariate statistical analysis showed that Fe, Mn and Na in leaf blades and Fe and Mn in leaf sheaths could be proportionally transferred to N. lugens. The relationship between most elements in adult female bodies and in the honeydew showed a positive correlation coefficient. There were significant differences in the contents of some elements in rice plants and N. lugens from different regions.

关键词： elements imidacloprid Nilaparvata lugens rice plant transference effect

Dynamic alterations in early intestinal development,microbiota and metabolome induced by in ovo feeding of L-arginine in a layer chick model

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Journal of Animal Science and Biotechnology 2020年第3期11卷 896-911页

作者： Dong Dai Shu-geng wu Hai-jun Zhang Guang-hai Qi Jing Wang Laboratory of Quality&Safety Risk Assessment for Animal Products on Feed Hazards(Beijing)of the Ministry of Agriculture&Rural Affairs and National Engineering Research Center of Biological FeedFeed Research InstituteChinese Academy of Agricultural Sciences12 Zhongguancun South St.Haidian DistrictBeijing 100081China

Background:Prenatal nutrition is crucial for embryonic development and neonatal growth,and has the potential to be a main determinant of life-long *** the present study,we used a layer chick model to investigate the effects of in ovo feeding(IOF)of L-arginine(Arg)on growth,intestinal development,intestinal microbiota and *** treatments included the non-injected control,saline-injected control,and saline containing 2,6,or 10 mg Arg ***:IOF Arg increased early intestinal index and villus height,and enhanced uptake of residual yolk lipid,contributing to subsequent improvement in the early growth performance of *** Arg supplementation also increased the early microbialα-diversity,the relative abundance of Lactobacillales and Clostridiales,and decreased the relative abundance of Proteobacteria of cecum in ***,the shift of cecal microbiota composition and the colonization of potential probiotics were accelerated by IOF of ***,metabolomics showed that metabolisms of galactose,taurine-conjugated bile acids and lipids were modulated to direct more energy and nutrients towards rapid growth of intestine at the beginning of post-hatch when embryos received IOF of ***:Prenatal Arg supplementation showed beneficial effects on the early intestinal development,cecal microbiota and host metabolism of layer chicks,contributing to subsequent improvement in the early growth *** findings provide new insight into the role of IOF of Arg in the establishment of the gut microbiota of newly-hatched layer chicks,and can expand our fundamental knowledge about prenatal nutrition,early bacterial colonization and intestinal development in neonate.

关键词： Development In ovo feeding Intestinal microbiota L-arginine Layer chick Metabolomics