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Geochemical significance of the relative enrichment of pristane and the negative excursion of δ^(13)C_(Pr) across the Permian-Triassic Boundary atMeishan, China

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Chinese Science Bulletin 2005年第19期50卷 2213-2225页

作者： WANG chunjiang LIU Yimei LIU Hongxiu zhu Lei SHI Quan Laboratory of Geochemistry and Environmental Sciences Faculty ofGeosciences China University of Petroleum Beijing 102249 China

Changes in the distribution of isoprenoid hy-drocarbons and in δ 13Ckero or δ 13CPr across the section from the Changxing Formation to the lower Yinkeng Formation at Meishan (the GSSP of PTB) are studied, in which a relative enrichment of pristane and a sharp shift in both δ 13Ckero and δ 13Cmole near the boundary are revealed. A possible mecha-nism for the abnormal accumulation of pristane near PTB is suggested: Lipids in some marine animals and their metabo-lites, rich in pristane, can be preserved and accumulate in some suitable depositing facies under certain special condi-tions, such as the catastrophic death of animals and/or de-veloping of an anoxic water column, and thus the pristane enrichment occurs in the sediment. The occurrences of iso-prenoid enrichment and high Pr/Ph ratios have been found in other typical marine anoxic sediments accompanied by mass extinction in various extent during the most important geological periods, such as Late Ordovician, end of Devonian,Early Jurassic and Late Cretaceous. These occurrences sup-port to a certain extent the above mechanism that interprets the genesis of a high Pr/Ph ratio in some typical marine an-oxic sediments. The synchronous sharp negative shifts in δ 13Cmole, δ 13Ckero and δ 13Ccarb from Beds 24 to 26 of the Me-ishan profile indicate that a sudden and strong variation of carbon source in the atmosphere-ocean system occurred during the quick but equable evolution from the end-Permian to Early Triassic, and the coupling between the pristane enrichment and negative shift in δ 13Ckero and δ 13CPr may well indicate the importance of the release of methane hydrates and marine anoxia in the end-Permian mass extinc-tion.

关键词：地球化学碳氢化合物同位素油脂 PTB

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Nozzle test system for droplet deposition characteristics of orchard air-assisted sprayer and its application

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International Journal of Agricultural and Biological Engineering 2014年第2期7卷 122-129,I0003页

作者： Zhai Changyuan Zhao chunjiang Wang Xiu Li Wei Li Wei zhu Ruixiang College of Mechanical and Electronic Engineering Yangling 712100ShaanxiChina Northwest A&F University Yangling 712100ShaanxiChina National Engineering Research Centre for Information Technology in Agriculture Beijing 100097China

In order to obtain nozzle droplet deposition characteristics for sprayer mechanical design and variable spraying control algorithms,a nozzle droplet deposition characteristics test system for air-assisted spraying was *** test system can supply a stable wind site with precisely controlled air speed whose speed control ranges from 2 m/s to 16 m/s with maximum relative error of 4.5%.It can spray out a certain amount of liquid pesticide with adjustable spraying pressure which can be controlled with high precision while the maximum relative error is only 1.33%.The distribution of droplet deposition can be collected and measured by using the acquisition device and a pesticide deposition optical measurement *** experiment of two-dimensional nozzle flow measurement was carried *** results show that nozzle flow distribution is uniform and symmetric with“double-hump”shape in the spray ***-nozzle overlapped droplet deposition ranges from 85%to 116%relative to the *** nozzle droplet deposition experiment was *** experiment results show that in air-assisted spraying,the higher the wind speed,the less droplet deposition is affected by *** the wind speed is higher than 12 m/s and spraying distance is 0.80 m,droplet deposition is concentrated on the originally designated point and hardly affected by *** horizontal spray width becomes smaller with higher wind *** the wind speed is high,it can be considered that nozzle deposition only focuses on the nozzle center,if the position requirement is not very high in orchard spraying.

关键词： air-assisted spraying orchard sprayer flow distribution droplet deposition nozzle test system characteristics test system

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Winter wheat biomass estimation based on canopy spectra

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International Journal of Agricultural and Biological Engineering 2015年第6期8卷 30-36页

作者： Zheng Ling zhu Dazhou Liang Dong Zhang Baohua Wang Cheng Zhao chunjiang Beijing Research Center for Information Technology in Agriculture Beijing 100097China School of Electronic Information Engineering Anhui UniversityHefei 230039China

The winter wheat aboveground biomass is an important agronomic parameter to estimate the growth status,and evaluate the yield and *** technique provides a nondestructive and fast method for estimating the winter wheat *** order to find the optimum model by analyzing the wheat canopy spectral characteristic during the whole growth period,field trails were conducted at the National Demonstration Base of Precision Agriculture in Beijing Xiaotangshan town.A portable spectrometer(200-1100 nm)was used to collect the wheat canopy spectra of different varieties at the different growth stages(green stage,jointing stage,booting stage,heading stage and filling stage),clipping the winter wheat at ground level at the same *** and correlation analysis were used to establish the winter wheat biomass estimation models in this *** results showed that the biggest different bands of the winter wheat canopy spectral reflection curves mainly lied along the blue and near-infrared *** spectral reflectance at 678 nm in the visible light range had the best correlation with the biomass(correlation=0.724).The monadic regression analysis,the multiple regression analysis and the partial least squares regression analysis were applied to establish the biomass estimation models,among which the partial least squares regression(PLS)model had higher modeling *** R2 of the calibration and validation were 0.916 and 0.911,*** root-mean-square error(RMSE)of the calibration and validation were 0.090 kg and 0.094 kg(Sample area 50 cm×60 cm).The results indicated that the PLS model(400-1000 nm)could fully estimate the aboveground biomass in the whole growth period of wheat with a better measurement accuracy.

关键词： winter wheat biomass canopy spectra crop growth period partial least square regression

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一株多重耐药大肠杆菌全基因组测序及其耐药性分析

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中国农业科技导报 2024年第6期26卷 113-121页

作者：李海利徐引弟王治方朱文豪张立宪马春江河南省农业科学院畜牧研究所郑州450002 哈密市动物疫病预防控制中心新疆哈密839001

为了解大肠杆菌携带的粘菌素耐药基因并筛选敏感药物,解决多重耐药和动物临床无药可选的困局,采用16S rRNA菌种全基因组测序,PCR筛查mcr-4、mcr-5、blaTEM和AmpC酶耐药基因,应用BLAST和MEGA软件进行生物信息学和系统进化树分析,并对该... 详细信息

为了解大肠杆菌携带的粘菌素耐药基因并筛选敏感药物,解决多重耐药和动物临床无药可选的困局,采用16S rRNA菌种全基因组测序,PCR筛查mcr-4、mcr-5、blaTEM和AmpC酶耐药基因,应用BLAST和MEGA软件进行生物信息学和系统进化树分析,并对该菌株进行了78种抗生素抗菌药物敏感性测试及4种天然植物提取物(黄藤素、黄连素、黄芩苷和博落回)的抑菌、杀菌效果试验。结果表明,从2021年(1—12月)和2022年(1—6月)猪临床腹泻病例肠道中分离鉴定的145株大肠埃希菌(Escherichia coli,***)中,鉴定出1株同时携带粘菌素耐药基因(mcr-4,mcr-5)和β内酰胺酶blaTEM、AmpC基因的猪源大肠埃希氏菌临床菌株HN2149。78种抗生素药敏试验结果显示,HN2149菌株对头孢吡肟、头孢地嗪、磷霉素、头孢克肟、头孢唑林、头孢哌酮、美洛培南、头孢西丁、头孢呋辛、头孢曲松、头孢噻肟、头孢他啶、替卡西林/克拉维酸、头孢哌酮/舒巴坦、氨曲南、哌拉西林/他唑巴坦、头孢噻肟/克拉维酸、头孢唑肟、头孢美唑、头孢他啶/克拉维酸和头孢他美敏感,对其余57种抗菌药物表现为耐药。4种植物提取物的药敏结果显示,博落回对菌株HN2149的抑菌、杀菌效果较好,其余3种提取物均对该菌株无抑菌和杀菌效果。以上研究结果为猪大肠杆菌病的防控提供参考。

关键词：碳青霉烯酶 β-内酰胺酶 mcr-4 mcr-5 blaTEM AmpC 大肠埃希氏菌细菌耐药

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盐酸普鲁卡因对人白血病HL-60细胞ID4基因甲基化状态的影响

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华夏医学 2016年第5期29卷 12-16页

作者：林文远朱春江刘冯陈蓓莉农庆伟吴贤义桂林医学院附属医院血液科广西桂林541001

目的:探讨盐酸普鲁卡因对体外培养的人白血病HL-60细胞ID4基因甲基化状态的影响。方法:体外培养HL-60细胞,使用不同浓度(2 mmol/L、4 mmol/L、6 mmol/L)的普鲁卡因处理细胞,分别采用MS-HRM、RT-PCR法检测HL-60细胞ID4基因启动子区域的... 详细信息

目的:探讨盐酸普鲁卡因对体外培养的人白血病HL-60细胞ID4基因甲基化状态的影响。方法:体外培养HL-60细胞,使用不同浓度(2 mmol/L、4 mmol/L、6 mmol/L)的普鲁卡因处理细胞,分别采用MS-HRM、RT-PCR法检测HL-60细胞ID4基因启动子区域的甲基化状态和ID4m RNA的表达。结果:HL-60细胞ID4基因在普鲁卡因作用下呈现明显的去甲基化状态,ID4m RNA表达明显增加,且以上改变均随药物浓度的增加而增强(P<0.05)。结论:盐酸普鲁卡因对HL-60细胞的ID4基因启动子区域有去甲基化作用,上调细胞ID4 m RNA的表达。

关键词：盐酸普鲁卡因 ID4基因甲基化 HL-60细胞

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Intelligent Recommendation and Matching Method for Agricultural Knowledge Based on Context-Aware Models

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Journal of Beijing Institute of Technology 2023年第3期32卷 341-351页

作者： Chang Liu Huarui Wu Huaji zhu Yisheng Miao Jingqiu Gu chunjiang Zhao National Engineering Research Center for Information Technology in Agriculture Beijing 100097China Information Technology Research Center Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China Key Laboratory of Digital Village Technology Ministry of Agriculture and Rural AffairsBeijing 100097China

The personalized recommendation of the cloud platform for agricultural knowledge and agricultural intelligent service is one of the core technologies for the development of smart *** the implicit laws and dynamic characteristics of agricultural knowledge demand is a key problem to be solved *** order to enhance the matching ability of knowledge recommendation and service in human-computer interaction of cloud platform,the mechanism of agricultural knowledge intelligent recommendation service integrated with context-aware model was *** combining context data acquisition,data analysis and matching,and personalized knowledge recommendation,a framework for agricultural knowledge recommendation service is constructed to improve the ability to extract multidimensional information features and predict sequence *** the cloud platform for agricultural knowledge and agricultural intelligent service,this research aims to deliver interesting video service content to users in order to solve key problems faced by farmers,including planting technology,disease control,expert advice,*** the knowledge needs of different users can be met and user satisfaction can be improved.

关键词： situational awareness agricultural knowledge intelligent recommendation service match

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农业对外开放合作风险防范调查分析实证研究

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安徽农学通报 2022年第2期28卷 1-5页

作者：朱春江范郁尔骆汝九许强朱荣吴成洲吴瑶马文斌李进连云港职业技术学院江苏连云港222006 连云港市农业对外经济合作中心江苏连云港222000 河海大学江苏南京210098 重庆师范大学重庆401331

随着中国农业对外开放合作的不断推进,农业政策变动、国际农产品市场不稳定、汇率变动、贸易壁垒、跨文化冲突等一些深层次的风险问题逐步凸现出来,这势必影响到农业对外开放合作的进程。为了更好地应对风险,进行风险防控是实现农业对... 详细信息

随着中国农业对外开放合作的不断推进,农业政策变动、国际农产品市场不稳定、汇率变动、贸易壁垒、跨文化冲突等一些深层次的风险问题逐步凸现出来,这势必影响到农业对外开放合作的进程。为了更好地应对风险,进行风险防控是实现农业对外开放合作的关键环节。通过对政府、企业(公司)、高校及研究院所3个层面共65家单位进行抽样问卷调查,并对132份问卷进行统计分析。结果表明,政治风险中的“东道国政治稳定性”、经济风险中的“贸易壁垒风险”、社会文化风险中的“知识产权保护风险”、管理风险中的“战略决策风险”、突发事件风险中的“突发重大公共卫生事件风险”等是农业对外开放合作风险的重要防范指标。研究结果可为农业对外开放合作风险进行预警防范,为政府制定有关政策提供依据。

关键词：农业对外开放合作风险防范社会调查理论

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数字声波变密度测井仪数据采集系统

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石油仪器 2011年第5期25卷 28-30,102页

作者：杨亮曾晓英段俊东舒克宁张春江朱旭东中国石油集团测井公司随钻测井仪器研究中心中国石油集团测井公司华北事业部

介绍了一种基于C8051F060单片机的数字声波变密度测井仪数据采集系统。系统以C805IF060单片机为控制核心,利用单片机片内集成的16位分辨率的A/D对声波信号进行精确数据采集,为进一步准确地评价固井质量提供了可靠的资料。实践检验表明,... 详细信息

介绍了一种基于C8051F060单片机的数字声波变密度测井仪数据采集系统。系统以C805IF060单片机为控制核心,利用单片机片内集成的16位分辨率的A/D对声波信号进行精确数据采集,为进一步准确地评价固井质量提供了可靠的资料。实践检验表明,系统具有测试速度快、精度高、运行稳定、抗干扰能力强和成本低等特点。

关键词： C8051 F060 数字声波变密度测井仪数据采集

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Preparation and Properties of SiC Assembled Large Block for Blast Furnace Tuyeres

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China's Refractories 2023年第4期32卷 1-7页

作者： LYU chunjiang CHANG Cheng HUANG Yifei CAO Huiyan LI Jie zhu Chong State Key Laboratory of Advanced Refractories Sinosteel Luoyang Institute of Refractories Research Co.Ltd.Luoyang471039China

A SiC assembled large block for blast furnace tuyeres was prepared using silicon carbide particles(3-1 and 1-0.088 mm)and fine powder(<0.088 mm),silicon powder(<0.088 mm),industrial carbon black(N990),microsilica,ρ-Al_(2)O_(3) powder,*** raw *** developed block was compared with a silicon nitride bonded silicon carbide brick,a self-bonded silicon carbide brick and an imported self-bonded silicon carbide block to analyze and evaluate their service *** results show that:(1)in the 0-100 mm zone,the SiC large block mainly consists ofβ-SiC and nitrides such as O'-SiAlON,β-SiAlON,α-Si_(3)N_(4),and Si_(2)N_(2)O,the bulk density is 2.68-2.70 g·cm^(-3),the apparent porosity is 14%-15%,and the material structure is uniform;(2)in the 0-100 mm zone,β-SiC nano-whiskers intercalate with nitrides;with the depth increasing,the number of flocculentβ-SiC nano-whiskers increases,while the number of nitrides decreases;when the depth reaches 150 mm or more,the main bonding phases areβ-SiC and mullite;(3)compared with the reference products,the developed SiC large block has a good basic performance,and after alkali corrosion,the mass change rate is-0.1%,which is obviously superior to the imported self-bonded silicon carbide and the homemade silicon nitride bonded silicon carbide materials.

关键词： blast furnace for iron-making tuyere silicon carbide alkali corrosion resistance

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Insights on evolution of virulence and resistance from the whole-genome analysis of a predominant methicillin-resistant Staphylococcus aureus clone sequence type 239 in China

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Chinese Science Bulletin 2014年第11期59卷 1104-1112页

作者： Hongbin Chen Xi Yang Qi Wang chunjiang Zhao Henan Li Wenqiang He Xiaojuan Wang Feifei Zhang Zhanwei Wang Minjun Chen Baoli zhu Hui Wang Department of Clinical Laboratory Peking University People’s Hospital Key Laboratory of Pathogenic Microbiology & Immunology Institute of MicrobiologyChinese Academy of Sciences Department of Clinical Laboratory Peking Union Medical College Hospital

Earlier, we reported that ST239 was the15-year predominant methicillin-resistant Staphylococcus aureus(MRSA) clone in China. In this study, MRSA strain CN79 belonging to ST239 and isolated from blood was used to determine the whole genome sequence. Comparative genomics analysis was done between MRSA CN79and 25 sequenced S. aureus in the NCBI GenBank database. A total of 2,734 protein-encoding genes were identified in the MRSA CN79 genome, which carries 11antibiotic resistance genes and 65 virulence genes. Two prophages phiCN79A and phiNM3-like were found on the MRSA CN79 genome. MRSA CN79 carries 30 specific genes that are absent from the 25 sequenced S. aureus genomes. Most of them were prophage-related *** antibiotic resistance genes, such as b-lactamase and ABC-type multidrug transport system gene, were located on the genomic island mSab. The antibiotic resistance genes, such as tet(M), ermA1, and blaZ, were also located on different transposons. The virulence genes sea,map, hlb, and sak are located on phiNM3-like prophage and the exotoxin genes are carried on the genomic island mSaa. These results suggest that ST239 MRSA strains are widespread owing to horizontal acquisition of the mobile genetic elements harbored antibiotic resistance genes and virulence genes in response to environmental selective pressures, such as antibiotics and the human immune system during evolution.

关键词：金黄色葡萄球菌基因组分析毒力基因进化过程序列类型中国克隆 GenBank

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