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Small mammal community response to early meadow–forest succession

Forest Ecosystems 2017年第3期4卷 211-220页

作者： Linas bal?iauskas Au?ra ?epukien? laima bal?iauskien? Nature Research Centre

Background： With farmland afforestation becoming common policy in many European Union countries, we studied how early forest succession（from meadow to young stand） influences small mammal species composition, diversity,abundance and biomass. Despite numerous investigations into forest succession, almost no attention has been given to the small mammal community change in the early-successional forest ecosystems, starting with the pre-forest habitat and ending with stand formation and the establishment of tree dominance. We compared small mammal communities in meadows at the initial stage of regrowth（with saplings less than 10 cm in height）, in young forest（5–10 years old） and more advanced forest（15–20 years） in both cases of human-induced forest succession, where the trees had been planted, and natural forest succession, where natural regrowth of meadows had ***： The greatest diversity of small mammal species was recorded in the meadow（H = 2.95）, with a lower diversity found in the young forest（H = 2.61） and even lower in the advanced forest（H = 2.04）, the last habitat being the most monodominantic. The order of species dominance from Microtus sp.（M. arvalis, M. agrestis）, Myodes glareolus, Apodemus flavicollis, Sorex araneus, A. agrarius in the meadow changed to M. glareolus, S. araneus, M. arvalis,M. agrestis in the young forest and to M. glareolus, A. flavicollis, S. araneus in the advanced forest. The lowest relative abundance of small mammals was recorded in the meadow（18.19 ± 2.27 ind. Per 100 trap-days）, with Microtus voles being the most abundant. Relative abundance was higher in the young forest（22.72 ± 2.25 ind. Per 100 trap-days）,with Myodes glareolus being the most abundant（7.59 ± 0.96 ind. Per 100 trap-days） and at its highest in the advanced forest（23.91 ± 2.77 ind. Per 100 trap-days）, again with M. glareolus being the most abundant（15.54 ± 2.35 ind. Per100 trap-days）.Conclusions： Thus, our analysis suggests that that during early meadow-f

关键词： Afforestation Voles Mice Diversity Abundance Biomass

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Geographical clines in the size of the herb field mouse(Apodemus uralensis)

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Integrative Zoology 2020年第1期15卷 55-68页

作者： Linas balČIAUSKAS Albina AMSHOKOVA laima balčiauskienė Ana Maria BENEDEK Jan CICHOCKI Alexander CSANÁDY Philippe Gil DE MENDONÇA Victoria NISTREANU Nature Research Centre VilniusLithuania Tembotov Institute of Ecology of Mountain Territories RAS NalchikRussia Lucian Blaga University of Sibiu SibiuRomania University of Zielona Góra Zielona GóraPoland Department of Biology Faculty of Humanities and Natural SciencesUniversity of PrešovPrešovSlovakia CESAM University of LisbonLisbonPortugal Institute of Zoology Academy of Sciences of MoldovaChisinauMoldova

Patterns of body size variation along geographical gradients have long been searched for and generalized into eco-geographical ***,no rodent species has yet been analyzed in relation to the 3 dimensions of latitude,longitude and *** analyzed geographical clines and dimorphism of body and skull size in the herb field mouse(Apodemus uralensis)across the species range,based on field data and on data from the liter*** dimorphism in adult *** was not expressed at a large scale,while local patterns were in***-dependent size changes were most expressed in adult individuals:most characters of adults exceeded in size those of subadults,while subadult-juvenile size differences were only significant in body weight and length,zygomatic skull width,length of cranial diastema and breadth of *** central morphological niches along the clines being separated,*** populations showed a high degree of size overlap in morphological *** found the species to be characterized by high size variability,with the largest individuals inhabiting the eastern and southern edges of the distribution ***,hind foot and ear lengths were largest in the southern part of the range,in agreement with Allen’s *** main measurements that we analyzed,namely body mass,zygomatic skull width and condylobasal skull length,show the presence of 3 clines in the size of adult ***:(i)a decreasing south-north cline,opposing Bergmann’s rule;(ii)an increasing west-east cline,in accordance with Murphy’s rule;and(iii)an increasing altitudinal cline.

关键词： altitudinal cline Apodemus uralensis east-west cline south-north cline species range

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Bio-Based Rigid Polyurethane Foams for Cryogenic Insulation

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Journal of Renewable Materials 2024年第3期12卷 585-602页

作者： laima Vevere Beatrise Sture Vladimir Yakushin Mikelis Kirpluks Ugis Cabulis Latvian State Institute of Wood Chemistry RigaLV-1006Latvia

Cryogenic insulation material rigid polyurethane(PU)foams were developed using bio-based and recycled *** obtained from tall oil fatty acids produced as a side stream of wood biomass pulping and recycled polyethylene terephthalate were used to develop rigid PU foam *** 4th generation physical blowing agents with low global warming potential and low ozone depletion potential were used to develop rigid PU foam cryogenic insulation with excellent mechanical and thermal *** rigid PU foams had a thermal conductivity coefficient as low as 0.0171 W/m·K and an apparent density of 37-40 kg/m^(3).The developed rigid PU foams had anisotropic compression strength properties,which were higher parallel to the foaming ***,the compression strength was also influenced by the type of applied bio-based *** bio-based polyols with higher OH group functionality delivered higher crosslinking density of polymer matrix;thus,the mechanical properties were also *** mechanical strength of the foams increased when materials were tested at liquid nitrogen temperature due to the stiffening of the polymer *** thermal properties of the developed materials were determined using differential scanning calorimetry,dynamic mechanical analysis,and thermogravimetric analysis ***,the developed rigid PU foams had good adhesion to the aluminium substrate before and after applying cyroshock and an excellent safety coefficient of *** PU foams developed using Solstice LBA delivered adhesion strength of~0.5 MPa and may be considered for application as cryogenic insulation in the aerospace industry.

关键词： Cryogenic insulation polyurethanes tall oil 4th generation physical blowing agents

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Hf含量对湿化学法制备超细W-Y_(2)O_(3)复合材料显微组织与性能的影响

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中国有色金属学报 2024年第1期34卷 125-138页

作者：刘祯颜硕罗来马昝祥吴玉程合肥工业大学材料科学与工程学院合肥230009 合肥工业大学有色金属与加工技术国家地方联合工程研究中心合肥230009 合肥工业大学高性能铜合金材料及成形加工教育部工程研究中心合肥230009

本文在现有W-Y_(2)O_(3)材料基础上,引入微量Hf4+掺杂入Y_(2)O_(3),调节Y_(2)O_(3)与W晶粒之间的界面关系,从而改善W基材料的综合性能。通过改变Y与Hf元素的掺杂比例,获得纳米级W基复合粉体,在氢气气氛下常规烧结制备W-Y_(2)(Hf)O_(3)... 详细信息

本文在现有W-Y_(2)O_(3)材料基础上,引入微量Hf4+掺杂入Y_(2)O_(3),调节Y_(2)O_(3)与W晶粒之间的界面关系,从而改善W基材料的综合性能。通过改变Y与Hf元素的掺杂比例,获得纳米级W基复合粉体,在氢气气氛下常规烧结制备W-Y_(2)(Hf)O_(3)复合材料。采用SEM、TEM等表征手段对W-Y_(2)(Hf)O_(3)复合材料的性能进行表征分析,研究Y与Hf元素在材料中的作用规律。结果表明:掺杂Hf元素有利于后续氢气还原,在第二相掺杂量不变条件下,当Hf含量增加时,所获得的粉体粒径减小,W-3Y-7Hf的粒径约为100 nm,明显小于传统制备的W-Y_(2)O_(3)粉体。烧结后的块体晶粒尺寸细化,显微硬度和相对密度随之增大,成分为W-3Y-7Hf烧结块体显微硬度最高,为513.7HV_(0.2),致密度为97.6%。在钨基材料中同时添加Y与Hf元素会在钨晶粒的晶界与晶内处形成复合第二相氧化物Y_(2)Hf_(2)O_(7)颗粒,尺寸更小,弥散强化作用更强;其中,W-3Y-7Hf中第二相氧化物颗粒尺寸仅为200 nm左右,与钨晶界产生良好的界面结合关系,形成半共格界面。

关键词：纳米级钨基复合粉体湿化学法弥散强化复合第二相氧化物

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HfO_(2)掺杂对湿化学法制备W-20Cu复合材料微观组织和性能的影响

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中国有色金属学报 2024年第7期34卷 2318-2329页

作者：许皖南王彩艳丁希鹏罗来马吴玉程合肥工业大学材料科学与工程学院合肥230009 合肥工业大学教育部铜合金及成形加工工程研究中心合肥230009 合肥工业大学有色金属与加工技术国家地方联合工程研究中心合肥230009

采用湿化学法制备W-20Cu复合粉体,通过喷雾干燥法得到球壳状前驱体,再通过氢气还原成功将弥散分布的HfO_(2)第二相颗粒引入W-20Cu复合粉体,确定了引入的HfO_(2)在W-20Cu复合粉体中的存在形式以及分布状态。采用高温液相烧结制备了细小Hf... 详细信息

采用湿化学法制备W-20Cu复合粉体,通过喷雾干燥法得到球壳状前驱体,再通过氢气还原成功将弥散分布的HfO_(2)第二相颗粒引入W-20Cu复合粉体,确定了引入的HfO_(2)在W-20Cu复合粉体中的存在形式以及分布状态。采用高温液相烧结制备了细小HfO_(2)颗粒均匀分布的W-20Cu复合材料。结果表明:由于HfO_(2)颗粒在W颗粒表面和W/Cu界面间隙中弥散分布,抑制了W颗粒在烧结过程中的粗化,从而降低了W-W的连通性,使得W-20Cu复合材料表现出较高的综合性能。其中,烧结温度在1350℃时,块体的致密度较高,均为97%,掺杂0.5%HfO_(2)制备得到的复合材料综合性能最佳,其硬度最大可达到338HV,抗弯强度为826 MPa,热导率为209 W/(m·K)。

关键词：湿化学法 W-Cu复合材料 HfO_(2)颗粒综合性能

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Long-term changes in a small mammal community in a temperate zone meadow subject to seasonal floods and habitat transformation

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Integrative Zoology 2022年第3期17卷 443-455页

作者： Linas balCIAUSKAS laima balCiauskienE Laboratory of Mammalian Ecology Nature Research CentreVilniusLithuania

We tested small mammal(SM)community response to the influence of seasonal floods and habitat transformation in a temporal zone meadow(west Lithuania).The habitat transitioned from a natural flooded meadow in 2008–2012 to a mowed and pastured area in *** were trapped in late summer to autumn using lines of 25 traps(145 in total),the number of trapping sessions being one or several per *** tested the hypotheses that:(1)any reaction to the multiple disturbances is species-specific,that is,the relative abundance of SM species and their proportion in the community differs with respect to the flood magnitude and habitat transformation,and(2)at the guild level,disturbances favor habitat generalists,thereby changing the characteristics of SM *** average relative density of SM was 20.25 individuals per 100 trap nights(range 7.56–40.67),with 4-year-long cyclical changes of density *** separate years,we recorded from 4 to 9 species;Shannon’s diversity index varied from 0.46 to 2.19,with expressed change of the dominant *** generalist species were favored,while habitat specialists were *** the meadow transformation progressed,unfavored states in the SM community prevailed,with excessive numbers of granivore and herbivore species *** study suggests that multiple disturbances may lead to an increase in relative abundance,species richness,and diversity within the SM assemblages.

关键词： agricultural transformation diversity floods small mammals species richness

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钨纤维增韧钨基复合材料的研究进展

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机械工程材料 2024年第5期48卷 1-7页

作者：陈畅李宽路陈寅王珊汪京罗来马合肥工业大学材料科学与工程学院合肥230009 合肥工业大学智能制造技术研究院合肥230051 高性能铜合金材料及成形加工教育部工程研究中心合肥230009 航空结构件成形制造与装备安徽省重点实验室合肥230009

钨纤维增韧钨基复合材料作为一种理想的面向等离子体材料,可以不需要引入其他合金元素,通过充分发挥钨纤维本身的优异性能而提升其韧性。对钨纤维增韧钨基复合材料的增韧机理、增韧相类型、制备方法的研究现状进行了综述,重点介绍了钨... 详细信息

钨纤维增韧钨基复合材料作为一种理想的面向等离子体材料,可以不需要引入其他合金元素,通过充分发挥钨纤维本身的优异性能而提升其韧性。对钨纤维增韧钨基复合材料的增韧机理、增韧相类型、制备方法的研究现状进行了综述,重点介绍了钨纤维表面改性、钨纤维体积分数以及烧结温度对复合材料性能的影响,指出了该复合材料今后的研究方向。

关键词：钨基复合材料钨纤维增韧制备方法增韧机理力学性能

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SPS制备SPTAs块体过程的有限元模拟及其微观组织分析

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粉末冶金材料科学与工程 2024年第2期29卷 83-92页

作者：吕旷谭晓月涂清波丁杰马英群罗来马吴玉程中国科技开发院广西分院南宁530022 合肥工业大学材料科学与工程学院合肥230009 有色金属材料与加工国家地方工程研究中心合肥230009

本文结合实验和模拟,系统研究了放电等离子体烧结(spark plasma sintering,SPS)制备自钝化钨合金(self-passivation tungsten alloys,SPTAs)块体时的温度场、电流场对其组织均匀性的影响,建立烧结温度、时间、电流密度与块体微观组织的... 详细信息

本文结合实验和模拟,系统研究了放电等离子体烧结(spark plasma sintering,SPS)制备自钝化钨合金(self-passivation tungsten alloys,SPTAs)块体时的温度场、电流场对其组织均匀性的影响,建立烧结温度、时间、电流密度与块体微观组织的关系。结果表明:不同尺寸SPTAs块体在SPS固结时的温度沿径向分布不均,致使测量温度远低于样品实际温度。结合显微组织表征,发现提高样品烧结时的电流密度可缩短烧结时间,对获得细晶、均质结构样品有积极作用,但需要考虑样品因径向温度梯度引起的晶粒尺寸差异。本研究可为大尺寸SPTAs块体的SPS制备工艺设计提供参考。

关键词：自钝化钨合金放电等离子体烧结核聚变有限元电热耦合模型

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Effect of Silver Element on Microstructure and Properties of W-30Cu/TiC Composites

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Journal of Wuhan University of Technology(Materials Science) 2018年第6期33卷 1511-1515页

作者： CHEN Xiaoli LUO laima WU Yueheng School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Laboratory of Nonferrous Metal Material and Processing Engineering of Anhui Province Hefei 230009China

W-30 wt%Cu and TiC-50 wt%Ag were successfully synthesized by a novel simplified pretreatment followed by electroless plating. The 0 wt% TiC, 0.5 wt% TiC, and 0.5 wt%TiC-0.5 wt%Ag composite powders were added to W-30 wt%Cu composite powders by blending, and then reduced. The reduced W-30 Cu, W-30 Cu/0.5 TiC, and W-30 Cu-0.5 Ag/0.5 TiC composite powders were then compacted and sintered at 1 300 ℃ in protective hydrogen for 60 min. The phase and morphology of the composite powders and materials were analyzed using X-ray diffraction and field emission scanning electron microscopy. The relative density, electrical conductivity, and hardness of the sintered samples were examined. Results showed that W-30 Cu and TiC-Ag composite powders with uniform structure were obtained using simplified pretreatment followed by electroless plating. The addition of TiC particles can significantly increase the compressive strength and hardness of the W-30 Cu composite material but decrease the electrical conductivity. Next, 0.5 wt% Ag was added to prepare W-30 Cu-0.5 Ag/TiC composites with excellent electrical conductivity. The electrical conductivity of these composites(61.2%) is higher than that in the national standard(the imaginary line denotes electrical conductivity of GB IACS 42%) of 45.7%.

关键词： electroless plating silver element W-30Cu-0.5Ag/TiC composites electrical conductivity

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X-linked juvenile retinoschisis： phenotypic and genetic characterization

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International Journal of Ophthalmology(English edition) 2018年第11期11卷 1875-1878页

作者： Rasa Strupaite laima Ambrozaityte Loreta Cimbalistiene Rimvydas Asoklis Algirdas Utkus Center of Eye Diseases Clinic of Ear Nose Throat and EyeDiseases Institute of Clinical Medicine Faculty of MedicineVilnius University Vilnius LT-01513 Lithuania Department of Human and Medical Genetics Institute ofBiomedical Sciences Faculty of Medicine Vilnius UniversityVilnius LT-01513 Lithuania Center for Medical Genetics Vilnius University HospitalSantaros Klinikos Vilnius LT-08661 Lithuania

Juvenile X-linked retinoschisis（XLRS, MIM#312700） belongs to a group of the vitreoretinal dystrophies. We aimed to describe the phenotype-genotype correlation of three XLRS cases in juveniles with different novel mutations from the Lithuanian population. The patients demonstrated macular retinoschisis and typical cyst-like cavities on spectral-domain optical coherence tomography（SD-OCT） images. The mean central foveal thickness was 569.7 μm. Two patients presented with peripheral retinoschisis. Flash electroretinogram demonstrated a reduced b/a ratio（〈1.0） in all patients. RS1（NM_000330.3） gene coding exons Sanger sequencing was performed. RS1 c.599 G〉T（p.R200 L） mutation was detected in one case, showing to be pathogenic in silico analysis. c.（92_97） ins C（p.W33 fs） mutation was identified for another patient, indicating the variant is possibly damaging in silico analysis. The third case was identified with a pathogenic mutation c.422 C〉G（p.R141 H）, HGMD CM981753. These are the first cases of XLRS in the Lithuanian population confirmed by molecular genotyping. Presented patients had a different genotype but similar phenotypic traits.

关键词： X-linked retinoschisis RS1 mutation optical coherence tomography electroretinogram

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