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Wheat silage partially replacing oaten hay exhibited greater feed efficiency and fibre digestion despite low feed intake by feedlot lambs

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Animal Nutrition 2023年第4期15卷 332-340页

作者： Zhao-Yang Cui Wen-Juan Li Wei-Kang Wang Qi-Chao Wu yao-Wen Jiang Ailiyasi Aisikaer fan Zhang He-Wei Chen Hong-Jian Yang State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

This study aimed to investigate the feeding effect of wheat silage on growth performance,nutrient digestibility,rumen fermentation,and microbiota composition in feedlot ***-four male crossbred Chinese Han lambs(BW=2..8±0.67 kg,3 months of age)were randomly assigned to four ration groups with wheat silage replacing 0%(WS0),36%(WS36),64%(WS64),and 100%(WS100)of oaten hay on forage dry matter *** concentrate-to-forage ratio was 80:2. and the feeding trial lasted 52.*** wheat silage inclusion linearly decreased dry matter intake by 4%to 2.%(P2.6%to 357%,resulting in Firmicutes instead of Bacteroidota being the most abundant *** relative abundance of cellulolytic Ruminococcus numerically increased but that of amylolytic Prevotella(P<0.01)decreased as increasing wheat silage *** together,increasing wheat silage replacement of oaten hay by no more than 64%exhibited greater feed efficiency and fibre digestion despite low feed intake by feedlot lambs due to the change of Firmicutes-to-Bacteroidota ratio in the rumen.

关键词： Wheat silage Oaten hay Growth performance Nutrient digestibility Rumen fermentation Feedlot lamb

Simulation of the landform change process on a purple soil slope due to tillage erosion and water erosion using UAV technology

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Journal of Mountain science 2020年第6期17卷 1333-1344页

作者： YANG Chao SU Zheng-an fan Jian-rong fanG Hai-dong SHI Liang-tao ZHANG Jian-hui HE Zhou-{2. ZHOU Tao WANG Xiao-yi Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Research Center for Digital Mountain and Remote Sensing Application Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of science Beijing 100049China Institute of Tropical Eco-agriculture sciences Yunnan Academy of Agricultural SciencesYuanmou 651300China Forestry college Sichuan Agricultural UniversityChengdu 611130China

Both tillage erosion and water erosion are severe erosional forms that occur widely on sloping agricultural ***,previous studies have rarely considered the process of landform change due to continuous simulation experiments of alternating tillage erosion and water *** identify such changes,we applied a scouring experiment(at a 60 L min-1 water discharge rate based on precipitation data from the local meteorological station and the catchment area in the Yuanmou County,Yunnan Province,china)and a series of simulated tillage experiments where plots were consecutively tilled 5,10,and 15 times in rotation(representing 5 yr,10 yr,and 15 yr of tillage)at slope gradients of 5°,10°,and 2.°.Close-range photogrammetry(CRP)employing an unmanned aerial vehicle(UAV)and a real-time kinematic global positioning system(RTK-GPS)was used to measure landform changes,and highresolution digital elevation models(DEMs)were generated to calculate net soil loss ***,the CRP was determined to be accurate and applicable through the use of erosion *** average tillage erosion rates were 69.85,131.45,and 155.34 t·hm-2.tillage pass-1,and the average water erosion rates were 1892.52.2.61.76,and 4405.93 t·hm-2.h-1 for the 5°,10°,and 2.°sloping farmland plots,*** water erosion rates increased as tillage intensity increased,indicating that tillage erosion accelerates water *** these intensive tillage treatments,slope gradients gradually decreased,while the trend in slope gradients increased in runoff plots at the conclusion of the scouring *** to the original plots(prior to our experiments),interactions between tillage and water erosion caused no obvious change in the landform structure of the runoff plots,while the height of all the runoff plots *** findings showed that both tillage erosion and water erosion caused a pseudo-steady-state landform evolutionary mechanism and resulted in thin soil layers on cultivat

关键词： Landform change Tillage erosion Water erosion Close range photogrammetry Erosion pins Runoff plot

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山羊数字化育种管理系统设计及应用效果分析

河南农业科学 2024年第1期53卷 133-141页

作者：王龙威樊红灯杨红远梁家充姚新荣叶朗惠刘廷丹李贺白俊艳张俊北京市农林科学院信息技术研究中心北京100097 河南科技大学动物科技学院河南洛阳471300 云南省畜牧兽医科学院云南昆明650224 云南省种羊繁育推广中心云南昆明655299 北京派得伟业科技发展有限公司北京100097

针对山羊良种繁育体系不健全、良种自主率低、育种企业技术力量薄弱等现状,设计了以遗传评估和选种选配为核心业务功能的山羊数字化育种管理系统,并在云南省山羊养殖企业示范应用。基于系统的统计分析功能,分析了云上黑山羊和波尔山羊... 详细信息

针对山羊良种繁育体系不健全、良种自主率低、育种企业技术力量薄弱等现状,设计了以遗传评估和选种选配为核心业务功能的山羊数字化育种管理系统,并在云南省山羊养殖企业示范应用。基于系统的统计分析功能,分析了云上黑山羊和波尔山羊核心群体种羊数量、繁殖性能、生长性能、综合选择指数的变化情况。结果表明,通过山羊数字化育种管理系统的应用,提升了养殖企业生产管理和育种管理效力。2.2.年相较于2.19年,云上黑山羊核心群体增长3600余只,波尔山羊核心群体增长2.00余只;云上黑山羊初生窝质量由6.2. kg提升到6.71 kg,窝均产羔数由2.10只提升到2.12.(立新羊业有限公司)。2.2.年相较于2.19年,云上黑山羊核心群12.龄体质量由36.19 kg提升到38.97 kg,背膘厚由2.78 cm下降到2.67 cm;云上黑山羊公羊综合选择指数提升了0.71%,波尔山羊公羊综合选择指数提升了1.38%,云上黑山羊母羊综合选择指数提升了0.80%,波尔山羊母羊综合选择指数提升了1.17%。该系统已在示范应用场平稳运行,且功能完善,操作简便,为山羊企业持续选育优良品种提供了技术支持。

关键词：山羊数字化育种种质资源挖掘可视化示范应用

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The impacts of oxytetracycline on humification during manure composting can be alleviated by adjusting initial moisture contents as illustrated by NMR

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Journal of Integrative Agriculture 2021年第8期20卷 2277-2288页

作者： FENG yao WANG Gui-zhen LIU Yuan-wang CHENG Deng-miao fan Shuang-hu ZHAO Quansheng Jianming XUE ZHANG Shu-qing LI Zhao-jun Key Laboratory of Plant Nutrition and Fertilizer Ministry of Agriculture and Rural Affairs/China-New Zealand Joint Laboratory for Soil Molecular EcologyInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China college of Life science Langfang Normal UniversityLangfang 065000P.R.China college of Biology and the Environment Nanjing Forestry UniversityNanjing 210037P.R.China Scion Christchurch 8440New Zealand

Oxytetracycline(OTC)residues have been found in soil and water,and they may pose potential risks to agricultural ecological *** of the most impactful ways for OTC to enter the soil and water environments is through excrement used as organic ***,it is important to remove OTC during manure composting and to understand the transformation of the organic materials during composting in the presence of *** the present paper,chicken manure and wheat sawdust spiked with OTC were composted under different initial moisture contents(MC)to evaluate the degradation of OTC and changes of organic matter during the composting *** MC has a significant effect on OTC degradation during composting.A higher MC of 65% was more conducive to OTC degradation(77.4%)and compost maturity compared to the lower ***,the higher MC of 65%could increase the ammonia volatilization by promoting nitrification compared to the lower *** increase in the initial MC could improve the composting *** results illustrated that the presence of OTC could affect the internal transformation of aliphatics,and OTC inhibited compost ***,an initial MC of 55–65% can alleviate the impacts of OTC on humification during manure composting.

关键词： oxytetracycline degradation humification moisture content composting physico-chemical property

Three-dimensional silk fibroin microsphere-nanofiber scaffolds for vascular tissue engineering

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Medicine in Novel Technology and Devices 2021年第1期9卷 52-59页

作者： Qiang Liu Guoliang Ying Nan Jiang Ali KYetisen Danyu yao Xiaoying Xie Yubo fan Haifeng Liu Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical EngineeringBeijing Advanced Innovation Centre for Biomedical EngineeringBeihang UniversityBeijing100191People’s Republic of China Department of Chemistry Stanford UniversityCA94305USA School of Materials science and Engineering Wuhan Institute of TechnologyWuhan430205People’s Republic of China Division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolCambridgeMA02139USA School of Engineering and applied sciences Harvard UniversityCambridgeMA02138USA Department of Chemical Engineering Imperial College LondonLondonSW72AZUK School of Life Information science and Instrument Engineering Hangzhou Dianzi UniversityHangzhou310018Zhejiang ProvincePeople’s Republic of China

A significant limitation in the engineering of artificial small-diameter vascular scaffolds is that the number of endothelial cells(ECs)is not sufficient to generate a confluent coverage of the vascular scaffolds,so that the surfaces of vascular scaffolds form thrombus via platelet adhesion and *** decrease relies on three-dimensional(3D)scaffolds to mimic the natural extracellular matrix(ECM)as templates to regulate cell behavior and facilitate tissue ***,we developed 3D scaffolds consisting of silk fibroin(SF)nanofibers and homogeneous microspheres by electrospinning and *** nanofibers with diameters ranging from 2.0 to 350 nm doped with microspheres(2.10μm)formed bridge-shaped *** were seeded and maintained on the 3D microsphere-nanofiber scaffolds with a mean fiber diameter of 300 nm.A 10%higher ratio of cell proliferation on 3D microsphere-nanofiber SF scaffolds was noted as compared to that on microporous and sponge-like SF scaffolds with small surface network fabricated by ***,the gene transcript levels including CD146,VE-C and PECAM-1 were better preserved on 3D microsphere-nanofiber SF scaffolds than those on freeze-dried ***,the developed 3D microsphere-nanofiber structure may have a myriad of applications in vascular tissue engineering scaffolds and cardiovascular devices.

关键词： Microfluidics Silk fibroin Electrospinning Micro/nanostructure Tissue engineering

The continuing shrinkage of snow cover in High Mountain Asia over the last four decades

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science Bulletin 2022年第20期67卷 2064-2068,M0003,M0004页

作者： Yupeng Li fan Sun Yaning Chen Baofu Li Gonghuan fang {2. Duan Qianqian Xia State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of sciences Beijing 10049China Akesu National Station of Observation and Research for Oasis Agro-ecosystem Akesu 843017China School of Geography and Tourism Qufu Normal UniversityRizhao 276826China college of Geography and Remote Sensing sciences Xinjiang UniversityUrumqi 830046China college of Biology and Geography Yili Normal UniversityYining 835000China

High Mountain Asia (HMA), known as Earth's "Third Pole" and"Asia's water tower",. is the largest glacier and snow reservoir onEarth except for the polar ice sheets (Text S1 and Fig. S1 online)。Snow is an important component of the HMA cryosphere, and itsvariability directly affects the water and energy balances in theregion [1,2. The average warming rate in the HMA region in recentdecades is approximately twofold higher than the average warm-ing rate in china and the world in the same period. The climatologyand trends of snow cover in the HMA have been investigated basedon station and satellite observations. However, these methodshave some limitations, resulting in large uncertainties or limita-tions in assessing long-term snow cover changes in the *** changes in the HMA region analyzed over a short timeseries may also lead to conclusions that are inconsistent with con-ventional assertions. Several studies of the temporal and spatialvariability of snow cover in the HMA region using short-termModerate Resolution lmaging Spectroradiometer data revealed nosignificant shrinkage in the snow cover area (SCA) [3].

关键词：随机森林青藏高原东南部结束日期敏感性分析 SCP 雪盖 SCD

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新型叠氮共聚醚黏合剂的固化反应动力学研究

中国胶粘剂 2018年第9期27卷 16-19,24页

作者：王薪申迎华姚维尚庞维强樊学忠太原理工大学化学化工学院山西太原030024 北京理工大学材料学院北京100081 西安近代化学研究所陕西西安710065

研究了BAMO-THF-GA(3,3-双叠氮甲基氧杂环丁烷-四氢呋喃-叠氮缩水甘油醚)与TDI(甲苯二异氰酸酯)粘接体系的固化反应动力学,通过非等温DSC(差示扫描量热)法对体系的固化过程进行热分析研究,借助n级反应动力学模型,通过Kissinger微分法、F... 详细信息

研究了BAMO-THF-GA(3,3-双叠氮甲基氧杂环丁烷-四氢呋喃-叠氮缩水甘油醚)与TDI(甲苯二异氰酸酯)粘接体系的固化反应动力学,通过非等温DSC(差示扫描量热)法对体系的固化过程进行热分析研究,借助n级反应动力学模型,通过Kissinger微分法、Flynn-Wall-Ozawa积分法及Crane方程对试验结果进行了处理,为该类固体推进剂的研制工艺提供一定的理论依据。研究结果表明:BAMO-THF-GA/TDI粘接体系的固化表观活化能Ea的平均值为91.18 k J/mol,指前因子A为5.82.1012.in-1,反应级数n为0.94,最佳固化温度为82.51℃。

关键词：叠氮共聚醚黏合剂固化动力学非等温DSC法

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电解液改善锂离子电池低温析锂研究进展

储能科学与技术 2024年第7期13卷 2192-2205页

作者：李泽珩徐磊姚雨星闫崇翟喜民郝雪纯陈爱兵黄佳琦别晓非孙焕丽范丽珍张强清华大学化学工程系绿电化工研究中心绿色反应工程与工艺北京市重点实验室北京100084 浙江大学化学工程与生物工程学院浙江杭州310058 北京理工大学前沿交叉科学研究院北京100081 中国第一汽车股份有限公司吉林长春130013 河北科技大学化学与制药工程学院河北石家庄050018 北京科技大学新材料技术研究院北京100083 清华大学碳中和研究院北京100084 清华大学山西清洁能源研究院山西太原030032

锂离子电池作为便携式电子产品和电动汽车的“心脏”,在推动人类社会的无化石燃料化中发挥着至关重要的作用。然而,在低温条件下(0℃及以下)充电时,锂离子电池电极极化急剧增大,导致了严重的析锂问题。通过合理设计低温电解液,降低低温... 详细信息

锂离子电池作为便携式电子产品和电动汽车的“心脏”,在推动人类社会的无化石燃料化中发挥着至关重要的作用。然而,在低温条件下(0℃及以下)充电时,锂离子电池电极极化急剧增大,导致了严重的析锂问题。通过合理设计低温电解液,降低低温充电时电极极化,并构建稳定的电解液-电极界面,可以有效遏制析锂及其对锂离子电池带来的不利影响。本文首先阐释了低温下锂离子电池析锂的形成机制,并指出低温电解液的设计是改善锂离子电池低温析锂行为的有效途径。接着,本文进一步介绍了缓解低温析锂问题的几种电解液设计策略,包括降低去溶剂化能垒的弱溶剂化电解液和共嵌入电解液、衍生低阻抗固态电解质界面膜(SEI)的局部高盐电解液以及钝化析锂的羧酸酯基高盐电解液,同时比较了这些策略的优劣势。最后,结合现有研究成果,展望了电解液调控低温析锂行为的未来研究方向,提出了发展实时析锂预警方法、采用实用化条件评估电解液抑制低温析锂能力以及设计兼顾电化学动力学和界面稳定性的高比能硅碳负极用低温电解液,以望实现低温锂离子电池的高容量发挥和长循环寿命。

关键词：析锂低温电解液锂离子电池电极极化

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祝尧《古赋辨体》的汉赋观

首都师范大学学报（社会科学版） 2003年第2期 59-65页

作者：踪凡首都师范大学文学院北京100089

祝尧《古赋辨体》对于汉赋的认识 ,包括赋之文体及渊源论、汉赋价值论、汉赋艺术结构论、汉赋作家作品论凡四个方面。这些观点都贯穿于该书的汉赋序论和赋作解题之中 ,论述时各有侧重而又互相呼应 ,观点鲜明而又论证细密 ,纵横开阖 ,声... 详细信息

祝尧《古赋辨体》对于汉赋的认识 ,包括赋之文体及渊源论、汉赋价值论、汉赋艺术结构论、汉赋作家作品论凡四个方面。这些观点都贯穿于该书的汉赋序论和赋作解题之中 ,论述时各有侧重而又互相呼应 ,观点鲜明而又论证细密 ,纵横开阖 ,声情并茂 ,极富思辩色彩与逻辑力量。《古赋辨体》

关键词：祝尧《古赋辨体》汉赋观理论性复兴