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Flotation techniques to improve viability of Juniperus polycarpos seed lots

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Journal of Forestry Research 2017年第2期28卷 231-239页

作者： Abolfazl Daneshvar Mulualem Tigabu Asaddollah Karimidoost Per Christer odén Southern Sw.dish Forest Research Centre Swedish University of Agricultural SciencesP.O.Box 49SE-230 53 AlnarpSweden Department of Natural Resources Gonbad Kavoos UniversityShahid Fallahi StreetP.O.Box 163GonbadIran Agriculture and Natural Resources Research Center of Golestan Province Beheshti Ave.P.O.Box ***GorganIran

The germination of freshly collected Juniperus polycarpos（K. Koch） seeds is very low.and attributed to the large proportion of nonviable seeds in the seed ***, the aim of this study w.s to improve seed lot quality by removing nonviable seeds using tw. flotation techniques： incubation-drying-separation（IDS） and modified specific gravity（MSG） separation. w. examined different IDS conditions（the specific incubation time, subsequent drying time and sorting media） for effectively sorting out nonviable seeds; and tested the feasibility of modified SG separation, w.ich involved soaking seeds in w.ter for a certain period before sorting in different concentrations of sucrose solution. Viable seeds w.re expected to absorb and metabolically bind more w.ter during soaking than dead seeds could, and hence be sorted effectively depending on the viscosity of the sucrose solution. The viability of the seeds that floated or sank w.s determined in a topographical tetrazolium chloride（TTC） test. For the IDS trial,7 days incubation follow.d by 9 h of drying and sedimentation in pure w.ter or 200 g L-1sucrose solution identified, respectively, 75 and 82 % of the seeds as viable（sunken） seeds. For the MSG trail, 77 % viable seeds w.re recovered in the sunken fraction w.en seeds w.re soaked for 48 h then immediately sorted in 600 g L-1sucrose solution. In both cases, the loss of viable seeds in the discarded floating fraction w.s only 4 %. The results demonstrate that both IDS and MSG separation techniques substantially improved seed lot viability, but MSG separation is simple and needs no modern seed handling facility, and its efficacy relies on seed mass（due to the initial soaking） and the specific density and viscosity of the flotation medium.

关键词： viable viability sorting sucrose tetrazolium incubation subsequent viscosity proportion immediately

Grow.h characteristics and reproductive output of dw.rf mistletoeinfected Juniperus polycarpos in Iran

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Journal of Forestry Research 2014年第4期25卷 827-834页

作者： Abolfazl Daneshvar Mulualem Tigabu Asaddollah Karimidoost Mostafa Farhadi Per Christer odén Sw.dish University of Agricultural Sciences Southern Swedish Forest Research Centre P.O Box 49 SE-230 53 Alnarp Sweden Department of Natural Resources Gonbad Kavous University Shahid Fallahi Street PO BOX: 163 Gonbad Iran Agriculture and Natural Resources Research Center of Golestan Province Beheshti Ave. PO Box *** Gorgan IRAN

Dw.rf mistletoes are parasitic flow.ring plants that infect conifers, resulting in substantial loss of grow.h and mortality. Recently, forest managers in Iran are contemplating w.ether infection of Juniperus polycarpos C. Koch forests by dw.rf mistletoe, Arceuthobium oxycedri （DC.） M. Bieb, influences tree vigor and contributes to insuffieient natural regeneration. The present study aimed at assessing the severity of infection and its impact on grow.h and reproductive output of./., polycar- pos. Infected and uninfected trees （n =20 each） w.re selected for assess- ment of diameter, height, crow. area, and crow. volume as w.ll as quantity and quality of cones and seeds. The severity of infection of trees w.s determined by Haw.sw.rth＇s 6-class dw.rf mistletoe rating （DMR） system. The DMR system revealed that 40% of the infected sample trees w.re lightly infected （DMR =1-2） and 60% w.re moderately infected （DMR =3--4）. Grow.h characteristics did not differ significantly （p 〉 0.05） betw.en infected and uninfected trees. How.ver, moderate infec- tion affected the reproductive output of./. polycarpos by significantly （p 〈0.05） reducing the mean number of cones per unit area of the crow., increasing the number of damaged seeds, and reducing seed size and seedgermination capacity. w. conclude that reproductive output of J.. poly- carpos is more sensitive than grow.h characters to moderate infection by juniper dw.rf mistletoe, and this might partly account for poor natural regeneration.

关键词： conifers Greek juniper forest health parasitic plant seed size

Physico-chemical characteristics and heavy metal concentrations of copper mine w.stes in Zambia:implications for pollution risk and restoration

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Journal of Forestry Research 2020年第4期31卷 1283-1293页

作者： Mutale N.Chileshe Stephen Syampungani Emma Sandell Festin Mulualem Tigabu Abolfazl Daneshvar Per Christer odén School of Natural Resources Copperbelt UniversityBox 21692KitweZambia Faculty of Forest Sciences Southern Swedish Forest Research CentreSwedish University of Agricultural SciencesBox 4923053 AlnarpLommaSweden Department of Biology Faculty of Basic Sciences and EngineeringGonbad Kavous UniversityShahid Fallahi StreetBasirat BlvdBox 163Gonbad-e-KavousGolestanIran

Soil characterization is a vital activity to develop appropriate and effective restoration protocols for mine w.stelands w.ile insights into the total content of heavy metals in the soil is an important step in estimating the hazards that the metals may pose to the vital roles of soil in the *** study addressed the follow.ng research questions:(1)To w.at extent do the physico-chemical characteristics vary betw.en mine w.ste sediments and the nearby forest soil?(2)Are the concentrations of heavy metals high enough to be considered as toxic?and(3)Are heavy metals present in mine w.ste sediments potential sources of pollution?w. hypothesized that the physicochemical characteristics of mine w.ste sediments are less favorably for plant establishment and grow.h w.ile the concentrations of heavy metals are very high,thus restricting the success of revegetation of mine w.ste *** w.ste sediments w.re sampled follow.ng a diagonal transect across tailings dams,overburden dump sites and the local forest soil from the top layer(0-20 cm)using a closed *** w.re analyzed for arsenic,barium,lead,cadmium,cobalt,copper,chromium,nickel,vanadium,and zinc as w.ll as for soil physico-chemical *** mine w.ste sediments w.re dominated by silt w.ilst the forest soil by sand particles,w.th significantly high bulk density in the *** the forest soil and overburden sediments w.re acidic than the alkaline tailings dam *** organic carbon and nitrogen contents w.re significantly low.in mine w.steland substrates but the concentration of Ca and Mg w.re significantly higher in tailings dam substrate than the forest *** concentrations of available P,K and Na w.re similar across *** mean concentrations of heavy metals w.re significantly(pw.ste sediments than the forest soil;except for cadmium(p=0.213).The order of contamination by heavy metals on the tailings w.s Cu>Co>Ba>Ni>As>Zn>Pb>Cr>V>Cd,and that on the overburd

关键词： Contamination factors Overburden material Phytostabilization Pollution load index Tailings dam

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烟台滨海景观带城市设计

城市规划 2002年第4期 97-100页

作者： od 205

Magnetic resonance imaging-guided focused ultrasound to increase localized blood-spinal cord barrier permeability

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Neural Regeneration Research 2017年第12期12卷 2045-2049页

作者： Allison H.Payne Gregory w.Haw.yluk Yoshimi Anzai Henrik odéen Megan A.Ostlie Ethan C.Reichert Amanda J.Stump Satoshi Minoshima Donna J.Cross Department of Radiology and Imaging Sciences University of Utah Salt Lake City UT USA Department of Neurosurgery University of Utah Salt Lake City UT USA

Spinal cord injury（SCI） affects thousands of people every year in the USA, and most patients are left w.th some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this issue, w. used magnetic resonance imaging-guided focused ultrasound（MRg FUS） as a non-invasive approach to increase permeability in the blood-spinal cord barrier（BSCB）. w. hypothesize that localized, controlled sonoporation of the BSCB by MRg FUS w.ll aid delivery of therapeutics to the injury. Here, w. report our preliminary findings for the ability of MRg FUS to increase BSCB permeability in the thoracic spinal cord of a normal rat model. First, an excised portion of normal rat spinal column w.s used to characterize the acoustic field and to estimate the insertion losses that could be expected in an MRg FUS blood spinal cord barrier opening. Then, in normal rats, MRg FUS w.s applied in combination w.th intravenously administered microbubbles to the spinal cord region. Permeability of the BSCB w.s indicated as signal enhancement by contrast administered prior to T1-w.ighted magnetic resonance imaging and verified by Evans blue dye. Neurological testing using the Basso, Beattie, and Breshnahan scale and the ladder w.lk w.s normal in 8 of 10 rats tested. Tw. rats show.d minor impairment indicating need for further refinement of parameters. No gross tissue damage w.s evident by histology. In this study, w. have opened successfully the blood spinal cord barrier in the thoracic region of the normal rat spine using magnetic resonance-guided focused ultrasound combined w.th microbubbles.

关键词： focused ultrasound spinal cord magnetic resonance imaging contrast-enhanced blood-spinalcord barrier

Some Explanation on Vector Diagram for Pow.r System Analysis

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Journal of Energy and Pow.r Engineering 2022年第1期16卷 7-12页

作者： Erdene Adiyasuren Enkh-od Erdene Mongolian University of Science and Technology Ulaanbaatar 14191Mongolia

The generating currents in the generator and the dissipating current at the load are completely different and they are out of *** magnitude of those currents is equal and the direction is opposite to each *** resistive,inductive and capacitive loads dissipate completely different voltages w.ich concern each of character of these *** direction of vectors of generated voltage and dissipated voltage must be draw. opposite to each other in the vector *** vector of consumed voltage at the resistive load and the vector of the current through this load are in phase w.ile the vector of generated voltage of the main source is out of *** resistive load consumes the voltage w.ich is generated by the main *** inductive load consumes the voltage w.ich is induced or generated in the inductor caused by the inductance due to the current flow.through the *** vectors of consumed voltage at the inductive load and the vector of current through this load are in phase w.ile the vector of generated voltage in the inductor caused by the inductance is out of *** capacitive load consumes the voltage w.ich is generated at the capacitor caused by the capacitance due to the current flow.through the *** vector of consumed voltage at the capacitive load and the vectors of current through this load are in phase w.ile the vector of generated voltage at the capacitor caused by the capacitance is out of phase.

关键词： Generated and dissipated voltage and current resistive inductive capacitive loads phase and vector diagram

Conducting Polymer-Based e-Refinery for Sustainable Hydrogen Peroxide Production

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Energy & Environmental Materials 2024年第2期7卷 334-342页

作者： Zhixing w. Penghui Ding Viktor Gueskine Robert Boyd Eric Daniel G■ow.cki Magnus odén Xaνier Crispin Magnus Berggren Emma M.Björk Mikhail Vagin Nanostructured Materials Department of PhysicsChemistry and Biology(IFM)Linköping UniversitySE 58183LinköpingSweden Laboratory of Organic Electronics Department of Science and Technology(ITN)Linköping UniversitySE 60174NorrköpingSweden

Electrocatalysis enables the industrial transition to sustainable production of chemicals using abundant precursors and electricity from renew.ble ***-centralized production of hydrogen peroxide(H_(2)O_(2))from w.ter and oxygen of air is highly desirable for daily life and *** report an effective electrochemical refinery(e-refinery)for H_(2)O_(2)by means of electrocatalysis-controlled comproportionation reaction(2_(H)O+o→2HO),feeding pure w.ter and oxygen *** nickel(Ⅱ)oxide(NiO)w.s used as electrocatalyst for oxygen evolution reaction(OER),producing oxygen at the *** polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)drove the oxygen reduction reaction(ORR),forming H_(2)O_(2)on the *** reactions w.re evaluated in both half-cell and device *** performance of the H_(2)O_(2)e-refinery,assembled on anion-exchange solid electrolyte and fed w.th pure w.ter,w.s limited by the unbalanced ionic *** of the operation conditions allow.d a conversion efficiency of 80%.

关键词： conducting polymer hydrogen peroxide nickel(Ⅱ)oxide oxygen evolution reaction oxygen reduction reaction

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XAC银行员工满意度研究

XAC银行员工满意度研究

作者： od-Erdene Erdenechuluun 河北大学

学位级别：硕士

由于人员及其知识的重要性日益增加,人力资源管理对于企业越来越重要。企业在改善运营时考虑的最重要因素之一是员工满意度。作为银行,有必要保持员工高满意度,因为它会影响服务质量。本论文的目的是分析Xac银行员工的满意度。该研究基... 详细信息

由于人员及其知识的重要性日益增加,人力资源管理对于企业越来越重要。企业在改善运营时考虑的最重要因素之一是员工满意度。作为银行,有必要保持员工高满意度,因为它会影响服务质量。本论文的目的是分析Xac银行员工的满意度。该研究基于赫茨伯格的双因素理论和马斯洛的理论。本研究采用定量研究设计。乌兰巴托约有780名Xac Bank员工。185名员工参与了这项研究调查。使用问卷收集原始数据。结果在Microsoft Excel中输入和分析。调查结果以表格、数字、频率和百分比表示。本文给出了切实可行的对策和建议。这项研究发现,Xac Bank的员工满意度高于平均水平,即3.7分。相信这反映了银行对员工的良好公司政策、人际关系、组织文化、工作环境和其他衡量标准。调查结果表明,员工获得了成长的机会,他们因工作或工作而获得适当的认可,员工有成就感。另一方面,还有一些问题需要改进。其中,薪资问题最为引人关注。一定比例的员工对晋升的可能性不满意。此外,管理者对下属工作责任的认识可能还有改进的空间,以便管理者能够提供适当的建设性反馈并对其提出合理的要求。此外,研究强调提高培训质量很重要。因此,本研究建议银行提供更多的金钱奖励和晋升机会,并提高工作保障。它还涉及文化对员工满意度的影响。是因为该银行是两个来自不同国家的实体的合并,其中一个是美国国际开发署资助的非银行金融机构。因此,来自不同国家的许多专业人士和实习生在银行工作。本论文的理论框架包括工作满意度和文化差异等概念。了解文化的特点并采取适当的措施是外商投资组织的基本业务问题之一。本研究通过Hofstede和Erin Meyer开发的模型对蒙古和美国文化进行了比较,揭示了具体差异,并包括了针对各个维度的对策。研究得出的结论仅对西飞银行有效,不能推广到其他机构。但是,它可以作为研究其他公司的参考。

关键词： XacBank 工作满意度双因素理论需求层次理论文化差异

乌兰巴托市高技术企业知识型员工的压力源研究

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乌兰巴托市高技术企业知识型员工的压力源研究

作者： od BAZARSAD（奥德）华东师范大学

学位级别：硕士

随着经济的发展,大都市中的高技术企业往往会吸纳很多知识型人才。因此对高技术企业中的知识型员工的压力源研究被视为是压力管理的新课题。随着蒙古国经济的发展,大城市中高技术知识型员工的压力成为新的问题。乌兰巴托市作为蒙古国的... 详细信息

随着经济的发展,大都市中的高技术企业往往会吸纳很多知识型人才。因此对高技术企业中的知识型员工的压力源研究被视为是压力管理的新课题。随着蒙古国经济的发展,大城市中高技术知识型员工的压力成为新的问题。乌兰巴托市作为蒙古国的首都,高技术企业最为发达而且知识型员工所面临压力相对蒙古国其他城市更为明显,因此本文选取乌兰巴托的高技术企业进行研究。本研究首先对压力、压力源、压力管理等概念进行梳理回顾,然后在结合社会学、心理学等学科的综合知识,对乌兰巴托市高技术企业的知识型员工的压力源进行了分析。通过对乌兰巴托市高技术企业知识员工的压力源研究后得出以下结论：(1)乌兰巴托市高技术企业知识型员工的压力源主要来自“职业发展”、“工作特征”、“工作/家庭平衡”、“人际关系”、“工资薪酬”和“文化适应”等六个方面;(2)地域、年龄、学历等都是影响男性员工与女性员工的重要调节变量;(3)对于31-40岁知识型员工而言,男性明显比女性感受到更多的压力。本研究在数据分析及结论的基础上,提出了如何对待管理高技术企业知识型员工并有效进行压力管理的对策,并提出了一系列的对策建议,如构建阳光透明的沟通平台以疏通员工压力,帮助员工建立新的职业发展渠道并将援助员工的计划考虑其中,加大政府的适度介入与支持,从而不单纯依赖企业。此外,随着经济全球化的发展,蒙古国传统的经济方式也发生了改变,希望本文能提高乌兰巴托市高技术企业雇主对知识分子的压力的关注,通过企业、政府和员工的齐心合力来共同疏通缓解知识型员工的压力,依赖企业-政府-员工的共同努力来缓解知识型员工的压力。

关键词：工作压力高技术企业知识员工