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4种粗饲料经纤维素酶发酵后产物的瘤胃降解特性研究

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饲料研究 2024年第9期47卷 23-30页

作者：胡湘云张村宇易显凤林波庞天德黄志朝广西农业职业技术大学广西南宁530007 广西大学动物科学技术学院广西南宁530005 广西辽大农业科技集团股份有限公司广西南宁530031

试验旨在研究甘蔗尾叶、玉米秸秆、象草、木薯枝4种粗饲料经纤维素酶(CE)发酵后的产物在水牛瘤胃中的降解特性,为水牛养殖中粗饲料的选择利用提供参考。试验以3头安装永久性瘤胃瘘管的水牛为试验动物,采用尼龙袋法测定4种粗饲料及其经C... 详细信息

试验旨在研究甘蔗尾叶、玉米秸秆、象草、木薯枝4种粗饲料经纤维素酶(CE)发酵后的产物在水牛瘤胃中的降解特性,为水牛养殖中粗饲料的选择利用提供参考。试验以3头安装永久性瘤胃瘘管的水牛为试验动物,采用尼龙袋法测定4种粗饲料及其经CE发酵后产物的营养成分及瘤胃降解特性。结果显示:发酵前,甘蔗尾叶与象草粗蛋白(CP)含量显著高于玉米秸秆和木薯枝(P甘蔗尾叶>玉米秸秆>木薯枝,象草的DM、NDF和ADF瘤胃有效降解率显著高于其他组(P甘蔗尾叶>玉米秸秆>木薯枝,添加CE能够改善4种粗饲料的瘤胃降解率。

关键词：甘蔗尾叶玉米秸秆象草木薯枝纤维素酶瘤胃降解率水牛

国家农业高新技术产业示范区“四链”融合机理分析——以吉林长春国家农高区为例

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科技管理研究 2024年第7期44卷 53-61页

作者：冯献李瑾范贝贝曹冰雪马晨北京市农林科学院信息技术研究中心北京100097 国家农业信息化工程技术研究中心北京100097

首先,在界定“四链”融合本质内涵的基础上,以吉林长春国家农业高新技术产业示范区(以下简称“农高区”)为例,对农高区“四链”融合的内在机理进行剖析。研究表明,“四链”深度融合的本质是以产业链、创新链、资金链、人才链四链有机融... 详细信息

首先,在界定“四链”融合本质内涵的基础上,以吉林长春国家农业高新技术产业示范区(以下简称“农高区”)为例,对农高区“四链”融合的内在机理进行剖析。研究表明,“四链”深度融合的本质是以产业链、创新链、资金链、人才链四链有机融合方式促进创新要素与资源汇聚,不断提升区域产业创新力与竞争力,形成持续高效运行的区域创新生态。研究认为,创新链是产业链发展的动力之源、是产业链各环节实现价值增值的基础,产业链是创新链落地生根的载体,创新链产业链协同是“四链”融合的核心,资金链和人才链是支撑,围绕产业链创新链精准配置资金链和人才链是根本保障,通过打造“四链”融通的现代产业体系有助于实现农高区产业链供应链的现代化。

关键词： “四链”融合国家农业高新技术产业示范区创新驱动乡村振兴

Evaluation of transmission risk of respiratory particles under different ventilation strategies in an elevator

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Building Simulation 2024年第5期17卷 771-784页

作者： Liangyu Zhu xian Li Bujin feng Fan Liu School of Civil Engineering and Architecture Linyi UniversityLinyi276000China College of Agriculture Shandong Agricultural UniversityTaian271018China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai200093China

People in elevators are at risk of respiratory infection because the elevator cabin is crowded and has poor *** exhaled particles may be inhaled by the susceptible person,deposited on the surface and suspended in the elevator,which can result in direct and indirect ***,whether the air vent designs adopted in the elevator can effectively reduce the transmission risk of respiratory particles remains *** this study,the dispersion of particles under four common ventilation strategies used in the commercial elevator was investigated by proven computational fluid dynamics(CFD)*** flow field was simulated with the RNG κ-ξ turbulence model and the Lagrangian method was adopted to track particle *** effects of air vent layout and airflow rate on particle transmission were *** found that more than 50% of exhaled particles(average value)were suspended in the cabin and difficult to discharge under the investigated ventilation *** deposited fraction of particles on the susceptible person reached up to 39.14% for infiltration ventilation,which led to a high risk of contact *** the ventilation rate could not significantly reduce the inhalation proportion of particles due to the poor airflow distribution inside the elevator.A more proper ventilation strategy should be explored for the elevator to control transmission risk.

关键词： particle dispersion transmission risk elevator ventilation strategy computational fluid dynamics(CFD)

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BIM技术在钢结构工程施工中的应用探讨

工程建设与设计 2024年第8期 88-90页

作者：闫飞李茂省于风仙李波北京东方雨虹防水技术股份有限公司北京100000 中科建通工程技术有限公司北京100000

总结了钢结构工程施工的难点与常见问题,详细介绍了BIM技术在可视化、信息共享、方案调整等方面的特点,探讨BIM技术在钢结构工程施工中的应用,分析了BIM技术在钢结构工程施工中的优势与局限,旨在解决施工中的难点问题,提高施工效率和质量。

关键词：钢结构工程 BIM技术应用探讨施工质量

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基于光速变换的激光打孔切割设备设计

机电工程技术 2024年第2期53卷 230-233页

作者：冯鲜杨汉嵩杨德云高源无锡太湖学院智能装备工程学院江苏无锡214064

传统机械加工存在加工效率低、环境友好性差等缺点,激光加工刚好解决了这些难题。激光切割打孔技术利用激光发生器输出高能量密度的激光束,激光束扫描加工表面,通过局部区域熔化气化,从而快速成型。鉴于此,设计了一款激光打孔切割设备... 详细信息

传统机械加工存在加工效率低、环境友好性差等缺点,激光加工刚好解决了这些难题。激光切割打孔技术利用激光发生器输出高能量密度的激光束,激光束扫描加工表面,通过局部区域熔化气化,从而快速成型。鉴于此,设计了一款激光打孔切割设备。首先从打孔切割设备的功能与性能需求入手,分析激光打孔切割工艺内容,提出打孔机机械系统方案。根据现代化设计理论原理,借助三维建模软件,完成了X、Y、Z轴的机械结构设计。包括电机的选取、导轨和丝杠的设计算,并完成了寿命以及强度刚度的校核。通过运用PLC控制技术来实现Z轴的移动,确保激光发生器移动至需要加工的位置。根据工艺需求确定了激光发生器的选型,并分析了激光切割速度和功率对加工结果的影响。

关键词：激光加工激光切割激光发生器切割速度

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Complex genesis of multiperiod fractures in the Middle Triassic Leikoupo Formation in the Pengzhou gas field, western Sichuan Basin, China

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Petroleum Science 2023年第1期20卷 161-176页

作者： Xiao-Fei Hu Hu-Cheng Deng Jian-Hua He Zhong-Min Shen xian-feng Peng College of Energy Chengdu University of TechnologyChengduSichuan 610059China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(Chengdu University of Technology) ChengduSichuan 610059China

The cumulative expression of multistage deformation is complex multiperiod fractures,which are commonly seen in tectonic *** Middle Triassic Leikoupo Formation in the western Sichuan Basin Depression,China,is a typical marine carbonate reservoir with natural fractures caused mainly by tectonic *** to outcrops,drill cores,image logging,and fluid inclusions,the fracture characteristics,types of natural fractures,and interactions of fractures are *** total,419 natural fractures in 493.2 m of cores from 7 wells are investigated,which are mainly shear and tensile fractures with a small number of weathering generated ***,the results of the stable isotope analysis of δ13C and δ18O,as well as the flow fluid inclusion data,reveal four tectonic periods of fractures with different *** on the history of regional tectonic evolution,indicating one period of weathering fractures ascribable to stratal uplift and three periods of structural fractures related to the sequential tectonic movements of the Longmenshan fault *** analyzing the interaction relationships of fractures,three types of fracture interaction relationships are observed:cutting,restraining,and *** four stages fractures are chronologically assigned to(1)the early Indosinian N-S trending compression,(2)the late Indosinian NW-SE compression,(3)the middle Yanshanian NE-SE compression,and(4)the early Himalayan E-W *** influence of natural fractures on gas migration and well production in marine carbonates is discussed,and indicates that tectonic fractures could provide seepage channels for gas migration and accumulation from near or distant hydrocarbon source rocks into the Middle Triassic Leikoupo *** study utilizes a pragmatic approach for understanding the fracture genesis mechanism in oil and gas field with multiperiod fractures.

关键词： Multiperiod fractures Interaction relationships Genesis mechanism Gas migration Leikoupo formation Sichuan basin

Properties of proto neutron star PSR J0737-3039A

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Chinese Physics C 2022年第10期46卷 207-214页

作者： xian-feng Zhao Shui-Rong Zhong Jian-Li Huo School of Sciences Southwest Petroleum UniversityChengdu 610500China

Using five sets of nucleon coupling constants(DD-MEI,GL85,GL97,GM1,and NL2),we find that the radius of the PNS PSR J0737-3039A is R=15.693-18.846 km,the central baryon density is ρ_(c)=0.247-0.359 fm^(-3),the central energy density is ε_(c)=4.30×10^(14)-6.49×10^(14) g·cm^(-3),and the central pressure is pc=3.79×10^(34)-5.85×10^(34) dyne·cm^(-2).With DD-MEI,GL85,GL97,and GM1,baryon octets appear in the PNS PSR *** NL2,only the baryons n,p,A,Σ^(0),∑^(-),Ξ^(0),and Ξ^(-)are *** to the same baryon density,the relative densities of the same baryon in the PNS PSR J0737-3039A calculated using different nucleon coupling constants differ *** central relative baryon densities of the PNS PSR J0737-3039A calculated using different nucleon coupling constants also differ greatly.

关键词： baryon relativistic mean field theory proto neutron star

Hemorrhagic transformation of ischemic cerebral proliferative angiopathy: A case report

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World Journal of Clinical Cases 2021年第20期9卷 5730-5736页

作者： Yu Xia xian-feng Yu Zhen-Juan Ma Zhong-Wu Sun Department of Neurology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina

BACKGROUND Cerebral proliferative angiopathy(CPA)is a rare vascular disease characterized by the presence of diffuse vascular proliferation,progressive vascular hyperflow and vasodilation of multiple vessels in the normal brain *** cerebral arteriovenous malformations,CPA has a mixed appearance between that of lesions with cell proliferation and endothelial *** date,the pathogenesis of CPA is unclear,in which changes induced by cortical ischemia in the elastic layer of the blood supply artery and smooth muscle cells may be *** SUMMARY In this article,we retrospectively analyzed a case of hemorrhagic transformation of ischemic CPA diagnosed by digital subtraction angiography and reviewed the related literature for further exploration of its pathogenesis,diagnosis and *** The information in the present case report may facilitate further clinical research on this cerebrovascular disease.

关键词： Hemorrhagic transformation Cerebral proliferative angiopathy Pathogenesis Diagnosis Treatment Case report

Sesquiterpene Esters from Salvia roborowskii

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Chinese Chemical Letters 2003年第11期14卷 1156-1158页

作者： Ya LI Ning LOU Yan Qi WU xian feng LIN Yu LI National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000

Two new sesquiterpene esters, 3b, 6b, 8a-triacetyl-4b, 5a-epoxy -1- oxogermacr- 10(14)-ene (1) and 3b, 6b, 8a-triacetyl-4b, 5a-epoxygermacr-1(10)-ene (2) were isolated from the whole plant of Salvia roborowskii Maxim.... 详细信息

关键词： Salvia roborowskii Labiatae sesquiterpene germacrane.