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甘南藏族自治州土地利用与生态风险时空演变及驱动因素

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干旱区研究 2024年第7期41卷 1140-1152页

作者：高鹏程岳艳妮鄢继选王世杰别强甘肃农业大学水利水电工程学院甘肃兰州730070 兰州交通大学测绘与地理信息学院甘肃兰州730070 地理国情监测技术应用国家地方联合工程研究中心甘肃兰州730070 甘肃省地理国情监测工程实验室甘肃兰州730070

本文以甘南藏族自治州为研究区域,基于1990—2020年每间隔10a的土地利用数据,拟探明甘南藏族自治州土地覆盖时空演变规律,分析土地利用时空变化和驱动因素之间的驱动机理,利用IDRISISelva软件,通过CA-Markov模型对甘南藏族自治州2030年... 详细信息

本文以甘南藏族自治州为研究区域,基于1990—2020年每间隔10a的土地利用数据,拟探明甘南藏族自治州土地覆盖时空演变规律,分析土地利用时空变化和驱动因素之间的驱动机理,利用IDRISISelva软件,通过CA-Markov模型对甘南藏族自治州2030年土地利用情况进行模拟预测并探讨了土地利用变化导致的生态风险变化情况。结果表明:(1)1990—2020年研究区土地利用结构发生了较大变化,草地和林地为优势土地利用类型,草地为主要转出土地利用类型。(2)1990—2020年耕地和建设用地的土地利用动态度较高,土地利用变化贡献率较高的是耕地、林地及草地,林地变化强度最大。(3)基于DEM、坡度、距道路距离、人口密度和经济密度因素对研究区土地利用变化驱动机理进行分析可见,人口和经济状况对土地利用结构影响较大。(4)采用CA-Markov模型对研究区2020年和2030年土地利用结构进行模拟预测的Kappa指数为0.88,预测精度较高。(5)研究区由土地利用变化导致生态风险较高的区域为夏河县和合作市北部、玛曲县东南部,其土地利用类型以未利用地、草地和林地为主。

关键词：土地利用 CA-Markov模型时空演变生态风险甘南藏族自治州

盐碱水养殖固体废物生物炭对硫酸盐型盐碱土的改良效果评价

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海洋渔业 2024年第2期46卷 195-205页

作者：朱润唐陶红来琦芳高鹏程周凯孙真么宗利上海理工大学环境与建筑学院上海200093 中国水产科学研究院东海水产研究所农业农村部低洼盐碱地水产养殖重点实验室盐碱水域渔业工程技术研究中心(上海)上海200090

为探索盐碱地水产养殖产生固体废物的利用途径,实现盐碱地田塘资源综合循环利用,用热解与水热炭化方法对盐碱水养殖固体废物进行处置,得到热解生物炭(BFM)和水热生物炭(HFM),以未经处理的养殖固体废物原料(FM)为对照,组成3种改良剂,每... 详细信息

为探索盐碱地水产养殖产生固体废物的利用途径,实现盐碱地田塘资源综合循环利用,用热解与水热炭化方法对盐碱水养殖固体废物进行处置,得到热解生物炭(BFM)和水热生物炭(HFM),以未经处理的养殖固体废物原料(FM)为对照,组成3种改良剂,每种改良剂设置3种剂量(2%、5%、8%)施加到硫酸盐型盐碱土中进行改良效果评价。结果表明:BFM和HFM氮磷钾含量丰富,表面羟基等官能团得到了保留。随着BFM、HFM、FM施加剂量从2%提升到8%,盐碱土速效氮含量分别提升了9.00%、10.21%~78.58%和27.64%~67.39%,总磷含量分别提升了14.98%~42.90%、16.62%~39.68%和4.70%~42.25%。施加改良剂后盐碱土pH未见明显改变,盐分随施加剂量的增加而增加,但HFM组盐碱指标保持在较低水平。施加改良剂可改善耐盐碱水稻的出苗率,5%BFM和5%HFM剂量组、2%FM剂量组3 d出苗率较对照组分别提高41.65%、66.65%和41.65%;而当改良剂施加量达到8%时,水稻出苗率显著降低(P<0.05)。综上,盐碱水养殖固体废物水热炭作为改良剂效果优于热解炭与原料,并且施加剂量应小于5%。研究结果可为盐碱水养殖固体废物的循环利用提供理论依据。

关键词：盐碱土养殖固体废物生物炭改良剂

Eff ects of oxytetracycline dihydrate and sulfamethoxazole on Microcystis aeruginosa and Chlamydomonas microsphaera

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Journal of Oceanology and Limnology 2021年第1期39卷 160-172页

作者： Xudong ZHOU Xincheng JIANG Shan gao Zhenjia WAN pengcheng gao College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China PowerChina Huadong Engineering Corporation Limited Hangzhou 311122China

The increasing use of pharmaceuticals has become a major environmental issue in *** presence of antibiotics in water may have deleterious eff ects on non-target aquatic organisms such as *** this study,a cyanobacterium and an alga species in surface waters,Microcystis aeruginosa and Chlamydomonas microsphaera,were exposed to 0,0.1,0.5,1.0,2.0,5.0,10.0,and 20.0 mg/L of oxytetracycline dihydrate(OXY)and sulfamethoxazole(SMZ)for 96 h to determine the eff ects of these antibiotics on the growth and surface ***,the photosynthetic activity and the contents of superoxide dismutase(SOD),malondialdehyde(MDA),and protein were measured to examine the biochemical characteristics of *** and *** under OXY and SMZ *** eff ects of both antibiotics on the growth of both species were concentration-dependent and characterized by low-dose stimulation and high-dose *** was more sensitive to both antibiotics than *** *** algal cell membranes of both species disintegrated after exposure to a high concentration of *** of the physiological parameters measured in this study were relatively stable at low concentrations of OXY and *** exposure to high concentrations of OXY and SMZ,photosynthetic activity decreased signifi cantly,whereas lipid peroxidation and the abundance of SOD,MDA,and protein increased signifi ***,low-dose antibiotics may increase algal blooms in eutrophic waters.

关键词： antibiotics cyanobacterium green algae physiology growth

切削液对金刚石线锯切割β-Ga_(2)O_(3)晶片表面质量的影响

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润滑与密封 2024年第3期49卷 133-142页

作者：王晓龙高鹏程檀柏梅杜浩毓王方圆河北工业大学电子信息工程学院天津300130 天津市电子材料与器件重点实验室天津300130 中国电子科技集团公司第四十六研究所天津300220

为了开发出更适合β-Ga_(2)O_(3)晶片切片的切削液,探讨金刚石线锯切片过程中不同切削液对β-Ga_(2)O_(3)晶片表面质量的影响,通过测量接触角和表面张力,研究不同切削液对β-Ga_(2)O_(3)晶片表面的润湿性。采用粗糙度测量仪、非接触式... 详细信息

为了开发出更适合β-Ga_(2)O_(3)晶片切片的切削液,探讨金刚石线锯切片过程中不同切削液对β-Ga_(2)O_(3)晶片表面质量的影响,通过测量接触角和表面张力,研究不同切削液对β-Ga_(2)O_(3)晶片表面的润湿性。采用粗糙度测量仪、非接触式测厚仪和扫描电镜(SEM)对晶片表面进行测试表征,研究去离子水、添加AEO-9的水基切削液和乳化切削液在不同工艺参数下对切割(010)面β-Ga_(2)O_(3)晶片的表面粗糙度、表面形貌、总厚度变化以及亚表面损伤层深度的影响。结果表明:与去离子水相比,添加AEO-9的水基切削液和乳化切削液均能有效降低β-Ga_(2)O_(3)表面的接触角和表面张力,表明2种切削液均可提高晶片表面润滑性;乳化切削液的效果随着工艺参数的变化而波动很大,只有在低切削热和大切削力的条件下,才能明显优化晶圆表面质量,而水基切削液可稳定地获得较高的晶片表面质量,更适用于β-Ga_(2)O_(3)晶片切割。

关键词： β-Ga_(2)O_(3)单晶线锯切割切削液润滑能力表面质量

Comparisons of microstructure homogeneity,texture and mechanical properties of AZ80 magnesium alloy fabricated by annular channel angular extrusion and backward extrusion

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Journal of Magnesium and Alloys 2020年第3期8卷 624-639页

作者： Xi Zhao Shuchang Li Zhimin Zhang pengcheng gao Shuailing Kan Fafa Yan School of Mechanical and Electrical Engineering North University of ChinaTaiyuan 030051China Engineering Technology Research Center for Integrated Precision Forming of Shanxi Province North University of ChinaTaiyuan 030051China China Aerodynamics Research and Development Center Mianyang 621000China The People's Liberation Army NO.5702 Xianyang 712000China Ningbo Branch of Chinese Academy of Ordnance Science Ningbo 315103China

This paper provided an efficient single pass severe plastic deformation(SPD)method,annular channel angular extrusion(ACAE),for fabricating AZ80 magnesium alloy shell *** effect of ACAE process on the microstructure homogeneity,texture,and mechanical properties of extruded part was experimentally *** comparison,conventional backward extrusion(BE)was also conducted on processing AZ80 part with same *** results showed that ACAE process has a better capacity to refine the microstructure and dramatic improve the deformation homogeneity of the extruded part than BE *** to two strong shear deformations were implemented,ACAE process could also concurrently modify the basal texture more notably than BE *** particular,a bimodal texture was found in ACAE extruded part,which was greatly related to the enhanced synergetic action of basal slip and secondaryslip caused by the effective shear *** uniform and superior hardness along the thickness and height of part were achieved via ACAE *** surveying of tensile tests also showed that the part fabricated by ACAE process exhibited significantly higher and far more homogeneous tensile properties with an excellent balance of strength and *** remarkable enhanced tensile properties of ACAE extruded part could be primarily attributed to the significant grain refinement,which provided a powerful grain boundary strengthening effect and meaningfully suppressed the development of twin-sized cracks during tensile *** was established that ACAE process seemed to be a very promising single pass SPD method for manufacturing Mg-based alloy shell parts with more homogeneous microstructure and superior performance.

关键词： Magnesium alloy Annular channel angular extrusion Microstructure Texture Mechanical properties

Large-scale Multi-modal Pre-trained Models: A Comprehensive Survey

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Machine Intelligence Research 2023年第4期20卷 447-482页

作者： Xiao Wang Guangyao Chen Guangwu Qian pengcheng gao Xiao-Yong Wei Yaowei Wang Yonghong Tian Wen gao Peng Cheng Laboratory Shenzhen518055China School of Computer Science and Technology Anhui UniversityHefei230601China School of Computer Science Peking UniversityBeijing100871China College of Computer Science Sichuan UniversityChengdu610065China

With the urgent demand for generalized deep models,many pre-trained big models are proposed,such as bidirectional encoder representations(BERT),vision transformer(ViT),generative pre-trained transformers(GPT),*** by the success of these models in single domains(like computer vision and natural language processing),the multi-modal pre-trained big models have also drawn more and more attention in recent *** this work,we give a comprehensive survey of these models and hope this paper could provide new insights and helps fresh researchers to track the most cutting-edge ***,we firstly introduce the background of multi-modal pre-training by reviewing the conventional deep learning,pre-training works in natural language process,computer vision,and ***,we introduce the task definition,key challenges,and advantages of multi-modal pre-training models(MM-PTMs),and discuss the MM-PTMs with a focus on data,objectives,network architectures,and knowledge enhanced *** that,we introduce the downstream tasks used for the validation of large-scale MM-PTMs,including generative,classification,and regression *** also give visualization and analysis of the model parameters and results on representative downstream ***,we point out possible research directions for this topic that may benefit future *** addition,we maintain a continuously updated paper list for large-scale pre-trained multi-modal big models:https://***/wangxiao5791509/MultiModal_BigModels_Survey.

关键词： Multi-modal(MM) pre-trained model(PTM) information fusion representation learning deep learning

牛支原体LRR5蛋白原核表达及其在牛支原体入侵宿主细胞过程中的作用分析

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微生物学报 2024年第5期64卷 1469-1482页

作者：冯雅茹周梦婷张瑜瑜张格高鹏程冉多良许健储岳峰李斌新疆农业大学动物医学学院新疆乌鲁木齐830052 新疆草食动物新药研究与创制重点实验室新疆乌鲁木齐830052 中国农业科学院兰州兽医研究所/兰州大学动物医学与生物安全学院、动物疫病防控全国重点实验室甘肃兰州730000 甘肃省病原生物学基础学科研究中心甘肃兰州730046

致病性支原体具有入侵宿主细胞的能力,这是其发挥致病作用的关键。介导支原体入侵宿主细胞的自身功能蛋白可能是一种潜在的药物或疫苗靶标。【目的】克隆表达牛支原体(Mycoplasma bovis)MBOVPG45_0564基因编码蛋白(命名为LRR5蛋白),并... 详细信息

致病性支原体具有入侵宿主细胞的能力,这是其发挥致病作用的关键。介导支原体入侵宿主细胞的自身功能蛋白可能是一种潜在的药物或疫苗靶标。【目的】克隆表达牛支原体(Mycoplasma bovis)MBOVPG45_0564基因编码蛋白(命名为LRR5蛋白),并探究其在***入侵宿主细胞过程中的作用。【方法】利用NCBI数据库对MBOVPG45_0564基因进行同源性分析,用Discovery Studio Client系统对LRR5蛋白进行蛋白结构预测;原核表达LRR5蛋白并制备其小鼠多克隆抗体,利用免疫电镜对LRR5蛋白进行亚细胞定位;通过平板计数、激光共聚焦显微镜观察LRR5抗体封闭后***对胎牛肺(embryonic bovine lung,EBL)细胞入侵率的变化;将LRR5蛋白偶联至荧光微球表面后,以激光共聚焦显微镜及高内涵活细胞成像系统观察微球进入EBL细胞情况。【结果】MBOVPG45_0564基因在牛支原体属中为保守基因,其编码蛋白LRR5为膜相关蛋白,空间构象呈典型的月牙状,多个重复的亮氨酸基序以超螺旋方式组装并形成螺线管蛋白质结构单元。LRR5抗体封闭后,***对EBL细胞的入侵率显著降低(P<0.05),荧光微球偶联LRR5蛋白后,荧光微球可成功进入EBL细胞。【结论】MBOVPG45_0564基因编码的LRR5蛋白定位在***膜上,在***入侵宿主细胞过程中发挥着重要作用。

关键词：牛支原体 MBOVPG45_0564基因入侵蛋白表达生物学功能

羊肠道蒙氏肠球菌和屎肠球菌的分离鉴定及益生特性分析

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微生物学通报 2024年第7期51卷 2546-2562页

作者：褚鑫龙马轲高鹏程付磊李学瑞冉维储岳峰蒋建军石河子大学动物科技学院新疆石河子832000 中国农业科学院兰州兽医研究所、兰州大学动物医学与生物安全学院、动物疫病防控全国重点实验室甘肃兰州730000 甘肃省病原生物学基础学科研究中心甘肃兰州730046

【背景】随着病原菌对抗生素耐药性的不断增加,在畜牧业养殖中研发安全可靠的抗生素替代品变得越来越重要。益生菌以其无毒、无残留、低成本且能有效补充肠道有益微生物等诸多优点,成为一种理想的抗生素替代品。【目的】从绵羊肠道共生... 详细信息

【背景】随着病原菌对抗生素耐药性的不断增加,在畜牧业养殖中研发安全可靠的抗生素替代品变得越来越重要。益生菌以其无毒、无残留、低成本且能有效补充肠道有益微生物等诸多优点,成为一种理想的抗生素替代品。【目的】从绵羊肠道共生菌中分离获得满足益生特性的益生菌。【方法】将健康绵羊肠道内容物及粪便在MRS培养基上分离纯化,利用形态学和16S rRNA基因序列分析鉴定分离菌株;通过抗菌活性分析、耐酸和耐胆盐能力测定、自聚集能力测定、抗生素敏感性分析及对小鼠的安全性测定等确定益生特性。【结果】从健康绵羊肠道中分离出多株肠道共生菌,经鉴定其中2株属于肠球菌,分别为蒙氏肠球菌(Enterococcus mundtii)A12和屎肠球菌(Enterococcus faecium)C1。抗菌分析显示,分离菌株A12和C1培养上清对金黄色葡萄球菌(Staphylococcus aureus)和猪霍乱沙门氏菌(Salmonella choleraesuis)均有很强的抗菌活性。耐受性分析显示分离菌株A12和C1具有良好的耐酸和耐胆盐特性,并且均具有很强的自聚集能力。药敏试验发现分离菌株A12和C1对多种抗生素敏感。小鼠体内安全性试验显示分离菌株A12和C1未使小鼠出现明显的病理变化,因此具备良好的安全性。【结论】分离纯化的2株肠道共生菌Enterococcus mundtii A12和Enterococcus faecium C1具有优良的益生特性和良好的安全性,具备作为益生菌开发的潜力。

关键词：羊肠道分离纯化肠球菌益生特性

Particle-Wave Dualism in Nanoconfined Space:Ultrafast Substance Flow

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Chemical Research in Chinese Universities 2022年第4期38卷 957-960页

作者： gao pengcheng MA Qun LIU Rui LOU Xiaoding HUANG Yu ZHANG Baocheng XIA Fan State Key Laboratory of Biogeology and Environmental Geology Engineering Research Center of Nano-Geomaterials of Ministry of EducationFaculty of Materials Science and ChemistryChina University of GeosciencesWuhan430074P.R.China School of Mathematics and Physics China University of GeosciencesWuhan430074P.R.China

Many researchers,however,found that(1)the flow of both liquid and gas through nanoscale pores is one to even seven orders of magnitude faster than that would be predicted from the classic Newton’s mechanic theories,such as the Hagen-Poiseuille equation,the Bernoulli’s principle,the Knudsen theory;(2)the seeming contradiction that K+channels conduct K+ions at maximal throughput rates while not permeating slightly smaller Na+ions,which have perplexed scientists for *** we propose a possible explanation for the above phenomena based on the Wave-Particle *** quantum effect on ultrafast flow could possibly provide a new perspective for studying the nature of the ion and molecule channels,which are the backbones for the biology,and possibly promote the development of new methods for energy conversion,desalination of sea water and even information systems.

关键词： Ultrafast transport Nanoconfined space Particle-Wave Dualism