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人群重金属混合暴露与肝功能的关联研究

中国无机分析化学 2024年第1期14卷 9-17页

作者：赵拴政殷国桓赵梅朵李昂吴景涛柳晓琳魏岚萍徐晶许群中国医学科学院基础医学研究所北京协和医学院基础学院流行病与卫生统计学系中国医学科学院环境与健康研究中心北京100005 锦州医科大学辽宁锦州121001 锦州市中心医院辽宁锦州121001

为探索单一及混合重金属暴露与肝功能的关联,为重金属暴露的健康效应提供证据,于2016—2018年在辽宁省的重金属污染区进行了横断面研究,共纳入了1 266名调查对象。收集了调查对象的血液样本和问卷信息,检测了血液样本中的铬(Cr)、镉(Cd... 详细信息

为探索单一及混合重金属暴露与肝功能的关联,为重金属暴露的健康效应提供证据,于2016—2018年在辽宁省的重金属污染区进行了横断面研究,共纳入了1 266名调查对象。收集了调查对象的血液样本和问卷信息,检测了血液样本中的铬(Cr)、镉(Cd)、钒(V)、锰(Mn)、铅(Pb)浓度用来代表调查对象的金属暴露,同时检测了血液样本中9种肝功能指标丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、天冬氨酸转氨酶与丙氨酸转氨酶之比(AST/ALT)、白蛋白(ALB)、球蛋白(gLB)、白蛋白与球蛋白之比(ALB/gLB)、总蛋白(TP)、总胆红素(TBIL)、直接胆红素(DBIL)的水平。首先采用一般线性回归模型探索单一重金属暴露与肝功能标志物的关联,进一步采用加权分位数和(WQS)回归与Quantile g-computation模型分析重金属混合暴露与肝功能标志物的关联并计算每种金属的贡献占比。研究发现,重金属Cr、Cd、V、Mn、Pb单一及混合暴露均与AST/ALT、gLB、TBIL、DBIL存在正向关联,而与ALB、ALB/gLB、TP存在负向关联(PgLB、TBIL的总体效应中贡献占比最大,Cr在混合重金属暴露对ALB/gLB、DBIL的总体效应中贡献占比最大,而Mn和Cd分别在混合重金属暴露对ALB、TP的总体效应中有最大的贡献占比。单一及混合重金属暴露均与肝功能标志物存在关联,可能导致肝功能损伤,其中V在正向关联中贡献最大,而Cr、Cd在负向关联中贡献最大。

关键词：重金属混合暴露肝功能流行病学

The Feasibility of Immobilization of Bioflocculant-producing Bacteria Using Mycelial Pellets as Biomass Carriers

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Journal of Harbin Institute of Technology(New Series) 2013年第3期20卷 1-6页

作者： Jin-Na Wang Fang Ma Jing-Bo g.o Ji-Xian Yang ang Li Ji-Hua Wang State Key Lab of Urban Water Resource and Environment Harbin Institute of Technology School of Civil and Architecture Engineering Northeast Dianli University School of Life Science and Technology Harbin Normal University

Bioflocculant-producing bacteria Ag.obacterium tumefaciens F2 and Bacillus sphaeicus F6 were immobilized onto mycelial pellets to investigate the bioflocculant-producing potential of this combined organism and the corresponding flocculating efficiency. The atomic force microscope ( AFM) images of mycelial surface indicate that the mycelia pellet can immobilize bioflocculant-producing bacteria F2 and F6 as a biomass carrier. The flocculating efficiency of bioflocculant produced by this combined organism was studied under the optimum flocculating conditions obtained by Response Surface Methodology ( RSM ) . The fermentation yield of the combined mycelial pellet is about 2. 6 g / L,which is higher than that of the free bacteria ( only 2. 2 g / L) . Flocculating efficiency of the combined mycelial pellet was comparable with that of bioflocculant generated by the free bacteria. The bioflocculant yield is enhanced and the flocculating efficiency of the co-culture is uninfluenced after immobilized with mycelial pellet as a carrier. In conclusion,the mycelial pellet is feasible as a biomass carrier for the immobilization of bioflocculant-producing bacteria.

关键词： bioflocculant-producing bacteria combined mycelial pellet immobilization biomass carrier

Surface pseudocapacitance of mesoporous Mo_(3)N_(2) nanowire anode toward reversible high-rate sodium-ion storage

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Journal of Energy Chemistry 2021年第4期30卷 295-303页

作者： Yalong Jiang Jun Dong Shuangshuang Tan Qiulong Wei Fangyu Xiong Wei Yang Yuanhao Shen Qingxun Zhang Zi'ang Liu Qinyou An Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina Department of Materials Science and Engineering Fujian Key Laboratory of Materials GenomeCollege of MaterialsXiamen UniversityXiamen 361005FujianChina Foshan Xianhu Laboratory of the Advanced Energy Science and Technology guangdong Laboratory Xianhu Hydrogen ValleyFoshan 528200GuangdongChina

Sodium-ion storage devices are highly desirable for large-scale energy storage applications owing to the wide availability of sodium resources and low *** metal nitrides(TMNs)are promising anode materials for sodium-ion storage,while their detailed reaction mechanism remains ***,we synthesize the mesoporous Mo3N2 nanowires(Meso-Mo_(3)N_(2)-NWs).The sodium-ion storage mechanism of Mo3N2 is systematically investigated through in-situ XRD,ex-situ experimental characterizations and detailed kinetics ***,the Mo_(3)N_(2) undergoes a surface pseudocapacitive redox charge storage *** from the rapid surface redox reaction,the Meso-Mo_(3)N_(2)-NWs anode delivers high specific capacity(282 m Ah g^(-1) at 0.1 A g^(-1)),excellent rate capability(87 m Ah g^(-1) at 16 A g^(-1))and long cycling stability(a capacity retention of 78.6%after 800 cycles at 1 A g^(-1)).The present work highlights that the surface pseudocapacitive sodium-ion storage mechanism enables to overcome the sluggish sodium-ion diffusion process,which opens a new direction to design and synthesize high-rate sodiumion storage materials.

关键词： Surface pseudocapacitance Sodium-ion storage Nitrogen vacancy Molybdenum nitride High-rate

Enhanced charge separation by continuous homojunction with spatially separated redox sites for hydrogen evolution

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Nano Research 2023年第10期16卷 12323-12330页

作者： Mingyuan Yu Tongyu Wang Chengxi Huang Fang Wu Xuan Liu Hailing Huo Hanwen Jian Zikun Liang Jingjing Ma Erjun Kan ang Li MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing School of ScienceNanjing University of Science and TechnologyNanjing 210094China College of Information Science and Technology Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of High-efficiency Utilization of Coal and green Chemical Engineering Ningxia UniversityYinchuan 750021China

Photocatalytic hydrogen generation represents a promising strategy for the establishment of a sustainable and environmentally friendly energy ***,the current solar-to-hydrogen conversion efficiency is not yet sufficient for practical hydrogen production,highlighting the need for further research and ***,we report the synthesis of a Sn-doped Tio_(2)continuous homojunction hollow sphere,achieved through controlled calcination *** incorporation of a gradient doping profile has been demonstrated to generate a gradient in the band edge energy,facilitating carrier orientation ***,the hollow sphere’s outer and inner sides provide spatially separated reaction sites allowing for the separate acceptance of holes and electrons,which enables the rapid utilization of carriers after *** a result,the hollow sphere Tio_(2)with gradient Sn doping exhibits a significantly increased hydrogen production rate of 20.1 mmol·g^(−1)·h^(−1).This study offers a compelling and effective approach to the designing and fabricating highly efficient nanostructured photocatalysts for solar energy conversion applications.

关键词： continuous homojunction spatially separated reaction sites charge separation hydrogen evolution

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微型飞行器的设计原则和策略

航空学报 2016年第1期37卷 69-80页

作者：昂海松南京航空航天大学微型飞行器研究中心南京210016

为了探索微型飞行器(MAV)总体设计方法,在简要介绍微型飞行器的概念与技术难点的基础上,笔者根据多年的MAV研究和试验,提出了对微型飞行器设计原则的思考,阐述了研究性和实用性MAV以及固定翼、扑翼和旋翼等不同类型MAV的设计特点。通过... 详细信息

为了探索微型飞行器(MAV)总体设计方法,在简要介绍微型飞行器的概念与技术难点的基础上,笔者根据多年的MAV研究和试验,提出了对微型飞行器设计原则的思考,阐述了研究性和实用性MAV以及固定翼、扑翼和旋翼等不同类型MAV的设计特点。通过MAV设计的矛盾与协调关系、设计方法和优化问题说明了MAV设计的特殊性。最后,展望了微型飞行器设计的发展方向,为微型飞行器总体设计研究提供了参考思路。

关键词：微型飞行器总体设计技术难点设计原则设计策略

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BAMo聚合物的合成与表征(英文)

含能材料 2006年第6期14卷 411-415页

作者： M.V.Maheshkumar M.J.Joseph K.Sreekumar H-g.ang Department of Applied Chemistry Cochin University of Science and Technology Cochin-682022 KeralaIndia Energetic Materials Research Centre Nanyang Technological University50 Nanyang Avenue Block N1-B4a-02Singapore 639 798

A new synthetic methodology has been developed for the synthesis of poly BAMo and poly BAMo-co-THF with controlled molecular weight and narrow molecular weight distribution. The synthesis of BCMo, the precursor of the BAMo monomer was accomplished using the reaction of Vilsmeir reagent with pentaerythritol. The BAMo monomer could be synthesized with an over all yield of 60% and polymerized using BF3·Et2o as the initiator and 1,4-butane diol as the co-initiator. Computational evaluation of the energy releasing properties of the poly BAMo derivatives was performed using gaussian algorithm. The theoretically calculated values agreed very well with the experimentally determined ones.

关键词：有机化学合成方法爆炸物 BAMo

Relation between gravitational mass and baryonic mass for non-rotating and rapidly rotating neutron stars

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Frontiers of physics 2020年第2期15卷 119-128页

作者： He g.o Shun-Ke Ai Zhou-Jian Cao Bing Zhang Zhen-Yu Zhu ang Li Nai-Bo Zhang Andreas Bauswein Department of Astronomy Beijing Normal UniversityBeijing 100875China Department of Physics and Astronomy University of Nevada Las VegasNV 89154USA Department of Astronomy Xiamen UniversityXiamen 361005China Institute for Theoretical Physics Max-von-Laue-Strasse 160438 FrankfurtGermany Shandong Provincial Key Laboratory of optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China gSI Helmholtzzentrum fiir Schwerionenforschung Planckstrafie 164291 DarmstadtGermany

With a selected sample of neutron star(NS)equations of state(EoSs)that are consistent with the current observations and have a range of maximum masses,we investigate the relations between NS gravitational mass Mg and baryonic mass and the relations between the maximum NS mass supported through uniform rotation(Mmax)and that of nonrotating NSs(Mtov).We find that for an EoS-independent quadratic,universal transformation formula(Mb=Mg+A×M^2/g),the best-fit A value is 0.080 for non-rotating NSs,0.064 for maximally rotating NSs,and 0.073 when NSs with arbitrary rotation are *** residual error of the transformation is?0.1M⊙ for non-spin or maximum-spin,but is as large as?0.2M⊙ for all *** different EoSs,we find that the parameter A for non-rotating NSs is proportional to R^-1/1.4(where R1.4 is NS radius for 1.4M⊙ in units of km).For a particular EoS,if one adopts the best-fit parameters for different spin periods,the residual error of the transformation is smaller,which is of the order of o.o1M⊙ for the quadratic form and less than o.o1M⊙ for the cubic form(Mb=Mg+A1×M^2/g+A2×M^3/g).We also find a very tight and general correlation between the normalized mass gain due to spin △m≡(Mmax-MToV)MToV and the spin period normalized to the Keplerian period P,i.e.,log10 △m=(-2.74±0.05)log10 P+log10(0.20±0.01),which is independent of EoS *** empirical relations are helpful to study NS-NS mergers with a long-lived NS merger product using multi-messenger *** application of our results to gW170817 is discussed.

关键词： gravitational waves

optical coherence tomography angiography in diabetic retinopathy: a review of current applications

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Eye and Vision 2019年第1期6卷 312-321页

作者： Kai Yuan Tey Kelvin Teo Anna C.S.Tan Kavya Devarajan Bingyao Tan Jacqueline Tan Leopold Schmetterer Marcus ang Hobart Clinical School Level 343 Collins StreetHobartTAS 7000Australia Singapore National Eye Centre 11 Third Hospital AveSingapore 168751Singapore Singapore Eye Research Institute 20 College Road Discovery TowerLevel 6 The AcademiaSingapore 169856Singapore Singapore National Eye Centre 11 Third Hospital AveSingapore 168751Duke-NUS Medical School8 College RdSingapore 169857Singapore

Backg.ound:Diabetic retinopathy(DR)is a leading cause of vision loss in ***,the standard imaging technique to monitor and prog.osticate DR and diabetic maculopathy is dye-based *** the introduction of optical coherence tomography angiography(oCTA),it may serve as a potential rapid,non-invasive imaging modality as an *** text:Recent studies on the role of oCTA in DR include the use of vascular parameters e.g.,vessel density,intercapillary spacing,vessel diameter index,length of vessels based on skeletonised oCTA,the total length of vessels,vascular architecture and area of the foveal avascular *** quantitative measures may be able to detect changes with the severity and progress of DR for clinical *** may also serve as a non-invasive imaging method to detect diabetic macula ischemia,which may help predict visual ***,there are many limitations of oCTA in DR,such as difficulty in segmentation between superficial and deep capillary plexus;and its use in diabetic macula edema where the presence of cystic spaces may affect image *** applications of oCTA in the anterior segment include detection of anterior segment ischemia and iris neovascularisation associated with proliferative DR and risk of neovascular ***:oCTA may potentially serve as a useful non-invasive imaging tool in the diag.osis and monitoring.of diabetic retinopathy and maculopathy in the *** studies may demonstrate how quantitative oCTA measures may have a role in detecting early retinal changes in patients with diabetes.

关键词： optical coherence tomography angiography Fluorescein angiography Diabetic retinopathy Screening Monitoring

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菲律宾BC家具企业发展战略研究

菲律宾BC家具企业发展战略研究

作者： ang, MICHELLE ANN g., RPh（谢慧莹）福建师范大学

学位级别：硕士

菲律宾经济的增长在很大程度上依赖于微型、小型和中型企业(MSME),其占全部注册企业比例高达99%。微型、小型和中型企业(MSME)通过创造新的就业机会、生产新的产品和服务以及激活市场竞争活力,在支持国民经济发展方面发挥着至关重要的... 详细信息

菲律宾经济的增长在很大程度上依赖于微型、小型和中型企业(MSME),其占全部注册企业比例高达99%。微型、小型和中型企业(MSME)通过创造新的就业机会、生产新的产品和服务以及激活市场竞争活力,在支持国民经济发展方面发挥着至关重要的作用。新冠疫情爆发使全球经济和社会遭到极大破坏,造成了极端的市场不稳定和波动,对商业和贸易产生了重大的负面影响。大多数中小微企业集中于传统产业,创新水平和抗风险能力较差,在新冠疫情冲击下,深受客户购物习惯和行为发生重大变化的新商业趋势的影响,甚至大量企业面临倒闭。然而,传统产业依然具有较强的民生需要和存在的价值。因此,在后疫情时代,深入探讨传统产业中小微企业面临的新机遇与挑战,探索中小微企业的创新发展战略,对企业寻求新的生机,推动就业和经济稳定发展具有重要意义。本文选取本人所在区域可调研的BC企业(为企业保密名字采用缩写)开展中小微企业发展战略案例研究。本人所在区域为菲律宾丹轆市重要的家具销售市场,BC企业为当地具有典型代表型家具销售企业。本文对BC企业实际业务内容、进货渠道、销售水平、财务数据和顾客等内部经营情况进行深入调研。采用PEST模型分析全球和菲律宾总体政治、经济、社会和技术等宏观环境,采用波特五力模型分析BC企业所面临的市场和行业环境,尤其是新冠疫情爆发以来出现的新的市场变化。结合企业面临的外部机遇与挑战,内部优势和劣势,对BC企业展开SWoT分析,并制定BC企业的短期、中期和长期发展战略。综合来看,BC企业在前期多年的经营发展过程中,形成了较为合理的组织结构,建立了具有竞争力的进货渠道,家具销售品种丰富,占据了较为良好的销售地段。但疫情爆发以来,宏观经济不景气,消费者购买能力受到影响,线下购买行为也减少,当地家具市场总体销售下滑。BC企业面临较为严重的销售业绩不佳,利润率逐月下降,甚至遭受损失。针对企业内外部环境发生的新变化,BC企业必须适应后疫情时代下新常态。为此,本文为期制定了“1261”发展战略。即打造一家创新型家具服务企业,构建线上线下双销售渠道,主攻六大家具装修风格,提供家具设计、制造、安装、售后一条龙服务。紧抓消费升级机遇提升服务水平,紧抓信息科技发展拓展线上销售渠道,以促使BC企业在激烈的家具竞争市场利用企业原有优势和新的发展机遇,形成超越竞争对手的特色比较优势,提高整体绩效。

关键词：战略管理创新发展战略中小微企业家具行业 PEST分析波特五力模型 SWoT分析