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Vertical patterns in plant diversity and their relations with environmental factors on the southern slope of the Tianshan Mountains(middle section)in Xinjiang(China)

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Journal of Mountain Science 2017年第4期14卷 742-757页

作者： liu bin Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi830011China College of Resource and Environmental Science Xinjiang UniversityUrumqi830046China College of Life Science Xinjiang Normal UniversityUrumqi830054China University of the Chinese Academy of Sciences Beijing100049China

The investigation of distribution patterns of species diversity is significant for successful biodiversity conservation. The spatial patterns of vegetation and different life-forms species diversity along an elevation gradient in the middle section of the southern slope of the Tianshan Mountains in Xinjiang, China were explored, using the detrended canonical correspondence analysis （DCCA） and the generalized additive model （GAM） methods based on a field survey of 53 sampling plots. In this work 158 species of seed plants were recorded, including 141 herbaceous, 14 shrub, and 2 tree species, in which the woody plants are very limited. 53 sampling plots were classified into 9 major plant communities. The results indicate that the herb communities were the most sensitive to changes in elevation gradient. The diversity indices of the community as a whole presented bimodal patterns. The peak values for the species diversities were found in the transition region between mountain steppe desert and mountain desert steppe （2,200-2,300m）, and in the alpine grassland region （2,900-3,100m）, while maximum species diversities were in the areas of intermediate environmental gradient. The main environmental factors on the distribution patterns in plant diversity were the elevation, soft water, total nitroeen, available nitrogen, organic matter, and total salt. The response tendency of the four diversity indices for the whole community to the soil environment was the same as that of the herb layers.

关键词： Species diversity Distribution pattern Plant community Soil properties Tianshan Mountains

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紫草对重症急性胰腺炎肺损伤的实验研究

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山西大同大学学报（自然科学版） 2017年第1期33卷 38-40,88页

作者：刘斌焰刘斌钰李祥邢雁霞郭敏芳刘宏山西大同大学生命科学学院山西大同037009

目的观察紫草对大鼠重症急性胰腺炎(SAP)肺组织病理变化及血清TNF-α、IL-6和NO的影响。方法选用Wistar大鼠随机分为假手术组(NS组)、模型组(SAP组)、紫草3 g/kg(H-紫草组)和紫草1 g/kg组(L-紫草组),检测术后24 h和72 h肺组织病理变化... 详细信息

目的观察紫草对大鼠重症急性胰腺炎(SAP)肺组织病理变化及血清TNF-α、IL-6和NO的影响。方法选用Wistar大鼠随机分为假手术组(NS组)、模型组(SAP组)、紫草3 g/kg(H-紫草组)和紫草1 g/kg组(L-紫草组),检测术后24 h和72 h肺组织病理变化及血清TNF-α、IL-6和NO水平。结果 H-紫草组和L-紫草组死亡率明显低于SAP组;H-紫草组和L-紫草组NO活性较高与SAP组相比P<0.01;而血清TNF-α和IL-6的含量显著降低,与SAP组比较。肺组织病理变化:SAP组可见肺间质充血、水肿,炎性细胞浸润严重,肺泡腔部分融合成肺大泡。H-紫草组和L-紫草组大鼠肺组织炎症反应明显较模型组减轻。结论紫草能降低SAP大鼠死亡率,提高血清NO活性、降低TNF-α和IL-6含量,减轻SAP所致的肺损伤。

关键词：紫草重症急性胰腺炎(SAP) 一氧化氮(NO) 肿瘤坏死因子(TNF-α) 白细胞介素-6(IL-6)

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Aggregation-induced emission: challenges and opportunities

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National Science Review 2021年第6期8卷 15-17页

作者： Wenbo Wu bin liu Institute of Molecular Aggregation Science Tianjin University Department of Chemical and Biomolecular Engineering National University of Singapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin University

Luminescent materials are everywhere in our daily life. However, most are not performing at their best performance because of the thorny aggregation-caused fluorescence quenching(ACQ) effect in molecular aggregates. Opposite to ACQ,aggregation-induced emission(AIE) describes the photophysical phenomenon in which non-luminescent molecules in solutions are induced to show bright emission upon aggregate formation, as a result of restriction of intramolecular motions(RIM) caused by intermolecular steric interaction(e.g. tetraphenylethene(TPE) in Fig. 1) [1].

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Electrical conductivity changes of bulk tin and Sn-3.0Ag-0.5Cu in bulk and in joints during isothermal aging

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 453-458页

作者： bin liu Fu Guo Institute of Building Environment and Energy Efficiency China Academy of Building Research Beijing 100044 China College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

The changes of electrical conductivity （resistance） between Sn-3.0Ag-0.5Cu solder joints and printed circuit board （PCB） assembly during aging at 125℃ were investigated by the four-point probe technique. The microstructural characterizations of interfacial layers between the solder matrix and the substrate were examined by optical microscopy and scanning electronic microscopy. Different types of specimens were designed to consider several factors. The experimental results indicate that electrical conductivities （resistances） and residual shear strengths of the solder joint specimens significantly decrease after 1000 h during isothermal aging. Microcracks generate in the solder matrix at the first 250 h. Besides, the evolutions of microstructural characterizations at the interface and the matrix of solder joints were noted in this research.

关键词： lead-free solder electrical conductivity isothermal aging, microcrack thermal stress

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2D hetero-structures based on transition metal dichalcogenides:fabrication,properties and applications

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Science Bulletin 2017年第16期62卷 1148-1161页

作者： Ping liu bin Xiang Department of Materials Science&Engineering CAS Key Lab of Materials for Energy Conversionand Synergetic Innovation Center of Quantum Information&Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China

Recently,two dimensional transition metal dichalcogenides MX_2(M = Mo,W,etc; X = S,Se,Te) have ignited immense interests because of their unique structural and physical properties for the potential applications in the nano-optoelectronics,valley-spintronics etc. In terms of the structural compatibility and van der Waals interaction,two dimensional(2D) MX_2 layers can be fabricated into various lateral and vertical hetero-structures. The atomically-thin hetero-structures comprising different layered MX_2 provide a new platform for exploring fundamental physics and device technologies with unprecedented phenomenon and extraordinary functionalities. In this review,we report the recent progress about the fabrication,properties and applications of 2D hetero-structures based on transition metal dichalcogenides.

关键词： Transition metal dichalcogenides Hetero-structures Chemical vapor deposition Charge transfer Optoelectronic devices

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Software defect prevention based on human error theories

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Chinese Journal of Aeronautics 2017年第3期30卷 1054-1070页

作者： Fuqun HUANG bin liu Institute for Dependability Engineering Seattle WA 98115 USA School of Reliability and System Engineering Beihang University Beijing 100083 China

Software defect prevention is an important way to reduce the defect introduction *** the primary cause of software defects,human error can be the key to understanding and preventing software *** paper proposes a defect prevention approach based on human error mechanisms：DPe *** approach includes both knowledge and regulation training in human error *** training provides programmers with explicit knowledge on why programmers commit errors,what kinds of errors tend to be committed under different circumstances,and how these errors can be *** training further helps programmers to promote the awareness and ability to prevent human errors through *** practice is facilitated by a problem solving checklist and a root cause identification *** paper provides a systematic framework that integrates knowledge across disciplines,e.g.,cognitive science,software psychology and software engineering to defend against human errors in software ***,we applied this approach in an international company at CMM Level 5 and a software development institution at CMM Level 1 in the Chinese Aviation *** application cases show that the approach is feasible and effective in promoting developers＇ ability to prevent software defects,independent of process maturity levels.

关键词： Human factor Human error Programming Root cause analysis Software defect prevention Software design Software quality Software psychology

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Strategic Response to a Powerful Downstream Retailer:Difference-Setting Wholesale Pricing Contract and Partial Forward Integration

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Journal of Systems Science and Systems Engineering 2022年第1期31卷 89-110页

作者： Conglin Hu bin liu Yunhui liu School of Economics and Management Shanghai Maritime UniversityShanghaiChina201306 Research Center for Contemporary Management Key Research Institute of Humanities and Social Sciences at UniversitiesSchool of Economics and ManagementTsinghua UniversityBeijing100084China

We study a supply chain consisted of a supplier and both retailers,and the supplier sells a single product through a dominant retailer and a weak *** aggressive bargaining behavior of the dominant retailer brings the supplier much concern and two feasible strategies are presented to respond to that:difference-setting wholesale pricing contract and integration with the weak *** investigate the decisions of supply chain members under each solution and find that,compared to the traditional form,the supplier always benefits from announcing the difference-setting wholesale pricing contract for it not only raises the marginal wholesale profits of both channels but also reduces the market share of the dominant retailer,thus potentially weakening its channel *** addition,we show that combining with the weak retailer is not a wise choice for suppliers when the dominant retailer with relatively little bargaining power enjoys a large market ***,by comparing the equilibria of these two solutions,we find that the optimal choice for suppliers depends not only on the difference in market share but also on the dominant retailer's bargaining power in the negotiation.

关键词： Channel power bargaining wholesale-price contract forward integration

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Comparison of Three Methods for Determination of Root Hydraulic Conductivity of Maize(Zea mays L.)Root System

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Agricultural Sciences in China 2010年第10期9卷 1438-1447页

作者： LI Qing-ming liu bin-bin State Key Laboratory of Crop Biology Shandong Agricultural University Tai'an 271018 P.R. China Key Laboratory of Horticultural Crop Biology Ministry of Agriculture/Shandong Agricultural University Tai'an 271018 P.R.China

Three techniques of root pressure probe, pressure chamber and high pressure flow meter were used to measure the hydraulic conductivities （Lpr） of whole root systems of young maize （Zea mays L.） seedlings grown hydroponically under either drought or normal water conditions. Compared to normal water conditions, drought stress simulated by polyethylene glycol 6 000 （osmotic potential =-0.2 MPa） reduced Lpr in the root system by over 50%. It indicated that water permeability in the roots decreased significantly when plants suffered from water shortages. Moreover, there was no significant difference （P〈 0.05） on the Lpr values in the root systems developed under a given water stress regime among the three techniques used. Therefore, all three methods are acceptable to study the hydraulic conductivity of maize seedling root systems. We have also highlighted some of the technical limitations of each method. It can be inferred that the root pressure probe is preferable for young maize seedlings because it is subtle and has the additional ability to determine solute transport properties, but the method is time consuming. Other advantages and disadvantages of each technique are discussed in order to acquaint researchers with basic information that could contribute to their choice of an appropriate technique for future studies.

关键词： hydraulic conductivity Zea mays L. root pressure probe pressure chamber high pressure flow meter

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Experimental Research on a Feasible Building Insulation Material Based Reed in China

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Journal of Thermal Science 2025年第1期34卷 176-187页

作者： liu Tiantian PENG Yizhe liu Lifang CAI Chenghan WANG Shuang LI Hongqiang College of Civil Engineering Hunan University College of Civil Engineering Hunan University of Science and Technology School of Energy and Power Jiangsu University of Science and Technology National Center for International Research Collaboration in Building Safety and Environment (NCIRCBSE) Hunan University Key Laboratory of Building Safety and Energy Efficiency of the Ministry of Education Hunan University

The seemingly useless reeds are prepared as thermal insulation materials,which not only meet the requirements of environmental sustainability but also enhance the added value of reeds,creating new economic *** hydrophobicity of raw biomass surfaces leads to problems such as weak bonding strength and non-dense structure in the formed materials,as well as issues related to the residual insect infestations on the *** this study,reed straw was used as the raw material,and foamed geopolymer was used as the binder to prepare building insulation materials based *** improve the interfacial adhesion performance between reed straw and foamed geopolymer,a thermochemical modification method-thermal carbonization,was *** this study,the mechanical properties and hydraulic properties of the studied materials with different degrees of surface thermal modification were tested,especially the fire resistance performance,and weathering resistance performance rarely found in published *** the surface thermal modification condition of reed straw was 250℃（30 min）,the comprehensive performance of reed-based building insulation materials was the best,when the studied material density was 321.3 kg/m3;the compressive strength was 0.59 MPa;the thermal conductivity was 0.101 W/（m·K）;the pH was 11.27;the moisture absorption rate was 25.1%,and the compressive strength loss rate in wet-dry cycles was 18.5%.In addition,it had excellent fire resistance performance and weathering resistance *** new material can be widely used to improve the thermal insulation of traditional buildings and as sandwich filler in prefabricated buildings,such as preparing insulating walls.

关键词： building insulation material based reed fire resistance performance interface adhesion properties pre-treatment of reeds weathering resistance performance

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生物3D打印仿生支架促进肩袖损伤后的愈合

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中国组织工程研究 2025年第22期29卷 4761-4770页

作者：徐杰酒精卫刘海峰赵斌山西医科大学第二医院骨科山西省太原市030000 骨与软组织损伤修复山西省重点实验室山西省太原市030000

背景:大多数肩袖损伤发生于冈上肌腱,由于肌腱组织缺少血管以及肩袖复杂的解剖结构,临床治疗效果非常有限。组织工程技术和干细胞生物学的快速发展为提高肌腱修复质量带来了新的希望。目的:通过生物3D打印技术制备人脐带间充质干细胞/... 详细信息

背景:大多数肩袖损伤发生于冈上肌腱,由于肌腱组织缺少血管以及肩袖复杂的解剖结构,临床治疗效果非常有限。组织工程技术和干细胞生物学的快速发展为提高肌腱修复质量带来了新的希望。目的:通过生物3D打印技术制备人脐带间充质干细胞/甲基丙烯酸酐化明胶复合支架,观察该支架修复肩袖损伤的效果。方法:(1)体外细胞实验:制备明胶微载体,将人脐带间充质干细胞接种于明胶微载体表面构建组织工程化干细胞。制备甲基丙烯酸酐化明胶水凝胶打印墨水,使用甲基丙烯酸酐化明胶水凝胶打印墨水重悬组织工程化干细胞,放入3D打印机的生物墨水容器中进行打印,蓝光照射固化5 min后即得人脐带间充质干细胞/甲基丙烯酸酐化明胶复合支架。通过死活染色、CCK-8实验检测支架内人脐带间充质干细胞的活性。(2)动物体内实验:采用随机区组设计方法将24只SD大鼠随机4组,每组6只:正常组不进行任何处理,肩袖损伤组、单纯支架组、细胞支架组建立冈上肌腱撕裂的肩袖损伤模型,单纯支架组、细胞支架组造模后分别将甲基丙烯酸酐化明胶支架、人脐带间充质干细胞/甲基丙烯酸酐化明胶复合支架植入肌腱损伤处。术后4周,分别进行大鼠行为学测试及肩袖冈上肌腱组织学病理组织形态观察。结果与结论:(1)体外细胞实验:死活染色结果显示,明胶微载体可减轻3D打印过程对人脐带间充质干细胞造成的损伤,随着培养时间的延长,支架内的人脐带间充质干细胞存活率升高;CCK-8实验结果显示,随着培养时间的延长,支架内的人脐带间充质干细胞活性无明显变化。(2)动物体内实验:行为学测试结果显示,相较于肩袖损伤组、单纯支架组,细胞支架组大鼠四肢运动功能明显改善;肩袖冈上肌腱苏木精-伊红与Masson染色结果显示,相较于肩袖损伤组、单纯支架组,细胞支架组肌纤维排列较规律,无明显的炎性细胞浸润,胶原容积百分比降低;免疫荧光染色结果显示,相较于肩袖损伤组、单纯支架组,细胞支架组肩袖冈上肌腱内白细胞介素6、肿瘤坏死因子α蛋白表达明显降低。(3)结果表明,生物3D打印的人脐带间充质干细胞/甲基丙烯酸酐化明胶复合支架可促进肩袖损伤组织修复再生。

关键词：肩袖损伤冈上肌腱损伤人脐带间充质干细胞细胞治疗组织工程化干细胞生物支架甲基丙烯酸化明胶生物3D打印

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