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生态灾害主题话语构架分析

河北北方学院学报（社会科学版） 2023年第1期39卷 27-30页

作者：刘娲路池丽霞张彩贞防灾科技学院外国语学院河北三河065201

以生态语言学中的认知生态语言学为理论框架,研究生态灾害主题话语的构架方式。生态灾害主题话语的构架方式分为非隐喻式和隐喻式两种。生态灾害话语的构架与自然灾害话语构架有很多相同之处,但仍存在很多差异。生态灾害话语的构架更加... 详细信息

以生态语言学中的认知生态语言学为理论框架,研究生态灾害主题话语的构架方式。生态灾害主题话语的构架方式分为非隐喻式和隐喻式两种。生态灾害话语的构架与自然灾害话语构架有很多相同之处,但仍存在很多差异。生态灾害话语的构架更加强调人类的作用,明确灾害的根源是人类自身的活动,强调灾害的可预见性和可改变性,同时一些表达也体现出人类对控制生态灾害的盲目自信和对自然力量的轻视。

关键词：认知生态语言学生态灾害话语构架社会文化语境

Analysis of the Harmfulness of water-Inrush from Coal Seam Floor Based on Seepage Instability Theory

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Journal of China University of Mining and Technology 2007年第4期17卷 453-458页

作者： KONg Hai-ling MIAO Xie-xing wa.g Lu-zhen ZHANg Yu CHEN Zhan-qing School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Yancheng Institute of Technology Yancheng Jiangsu 224003 China Xuhai College China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Resources ＆ geoscience China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

A theory of seepage instability was used to estimate the harmfulness of water-inrush from a coal seam floor in a particular coal mine of the Mining group,Xuzhou. Based on the stratum column chart in this coal mine,the distribu-tion of stress in mining floors when the long-wall mining was respectively pushed along to 100 m and to 150 m was simulated by using the numerical software (RFPA2D). The permeability parameters of the coal seam floor are described given the relationship between permeability parameters. Strain and the water-inrush-indices were calculated. The wa-ter-inrush-index was 67.2% when the working face was pushed to 100 m,showing that water-inrush is possible and it was 1630% when the working face was pushed to 150 m,showing that water-inrush is quite probable. The results show that as long-wall mining is pushed along,the failure zone is enlarged,the strain increased,and fissures developed cor-respondingly,resulting in the formation of water-inrush channels. Accompanied by the failure of the strata,the perme-ability increased exponentially. In contrast,the non-Darcy flow β factor and the acceleration coefficient decreased ex-ponentially,while the increase in the water-inrush-index was nearly exponential and the harmfulness of water-inrush in the coal mine increased accordingly.

关键词：煤层水涌渗漏不稳定性岩层

OE-PCR法扩增获得犬瘟热病毒缺失疏水区的融合蛋白基因片段

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中国兽医学报 2005年第6期25卷 585-587页

作者：乌仁高娃杨敬陈振文军事医学科学院实验动物中心北京100071

根据犬瘟热病毒(CDV)O nderstepoort株的核苷酸序列,设计合成引物,通过RT-PCR,从CDV O nderstepoort株RNA中扩增出2 197 bp的CDV全长融合蛋白(F)基因。将其与pgEM-T easy载体连接,通过软件分析其序列中的疏水区后,以pgEM-T/F为模板,PCR... 详细信息

根据犬瘟热病毒(CDV)O nderstepoort株的核苷酸序列,设计合成引物,通过RT-PCR,从CDV O nderstepoort株RNA中扩增出2 197 bp的CDV全长融合蛋白(F)基因。将其与pgEM-T easy载体连接,通过软件分析其序列中的疏水区后,以pgEM-T/F为模板,PCR扩增出约254 bp和1 017 bp的F蛋白疏水区外编码序列。以2个扩增产物为模板,以OE-PCR(overlap ex tens ion-PCR)扩增出约1 271 bp的缺失疏水区的F基因(dF),测序结果表明,dF的序列除在疏水区以4个甘氨酸序列替代外,其余部分与F基因的同源性为99.2%。这表明,OE-PCR扩增法已成功地使CDV F基因疏水区缺失。

关键词： CDV F基因疏水区缺失重叠延伸聚合酶链反应

Chromite-induced magnesium isotope fractionation during mafic magma differentiation

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Science Bulletin 2017年第22期62卷 1538-1546页

作者： Ben-Xun Su Yan Hu Fang-zhen Teng Ke-Zhang Qin Yang Bai Patrick Asamoah Sakyi Dong-Mei Tang Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SdencesBeijing 100029China Department of Earth and Space Sciences University of WashingtonSeattleWA 98195USA University of Chinese Academy of Sciences Beijing 100049China Department of Earth Science University of GhanaLegonAccra LG SGhana

To better understand the mechanism of Mg isotopic variation in magma systems, here we report high precision Mg isotopic data of 17 bulk rock samples including dunite, clinopyroxenite, hornblendite and gabbro and 10 pairs of dunite-hosted olivine and chromite separates from the well-characterized Alaskan-type Xiadong intrusion in NW China, which formed by continuous and high degree of lithological differentiation from mafic magmas. Chromite separates have highly variable δ^(26)Mg values from -0.10‰ to 0.40‰, and are consistently heavier than coexisting olivine separates(-0.39‰ to -0.15 T‰). Both mineral δ^(26)Mg values and the degrees of inter-mineral fractionation are well correlated with geochemical indicators of magma differentiation, indicating that these inter-sample and inter-mineral Mg isotope fractionations are caused by magma evolution. The δ^(26)Mg values range from -0.20‰ to -0.02‰ in the dunite,-043‰ in the clinopyroxenite,-043‰ to -0.28‰ in the hornblendite, 0.18 T‰ in the chromite-bearing hornblendite, and -0.56 T‰ to -0.16‰ in the gabbro. The Mg isotopic variations in different types of rocks are closely related to fractional crystallization and accumulation of different proportions of oxides vs. silicates. Chromite crystallization and accumulation is the most important factor in controlling Mg isotope fractionation during the formation of the Xiadong intrusion. Compared to basaltic and granitic magmas, differentiation of the Alaskan-type intrusions occurs at a relatively high oxygen fugacity, which favors chromite crystallization and consequently significant Mg isotope fractionations at both mineral and whole-rock scales. Therefore, Mg isotope systematics can be used to trace the degree of magma differentiation and related-mineralization.

关键词： Mg isotopes Alaskan-type intrusion Arc magmatism Magma differentiation Chromite

小气道三维CT定量参数对慢性阻塞性肺疾病评估价值的研究

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中国实用内科杂志 2022年第9期42卷 751-755页

作者：麻珍珍江德胜刘荣玉安徽医科大学第一附属医院呼吸与危重症科安徽合肥230022 六安世立医院影像科安徽六安237008

目的探讨三维CT定量测量小气道参数与肺功能相关性在慢性阻塞性肺疾病(COPD)患者评估中的价值。方法回顾性纳入2020年1月至2021年3月于安徽医科大学第一附属医院和六安世立医院呼吸与危重症医学科就诊的146例急性加重期COPD患者,根据慢... 详细信息

目的探讨三维CT定量测量小气道参数与肺功能相关性在慢性阻塞性肺疾病(COPD)患者评估中的价值。方法回顾性纳入2020年1月至2021年3月于安徽医科大学第一附属医院和六安世立医院呼吸与危重症医学科就诊的146例急性加重期COPD患者,根据慢性阻塞性肺疾病全球倡议(gOLD)分级标准将患者分为gOLD1~2级(62例)、gOLD3~4级(84例),收集患者胸部CT、肺功能、临床评分和6 min步行距离等资料。定量测量患者肺气肿指数(LAA%_(-950HU)),肺动脉与主动脉比值(PA∶A)以及第3~8级气道参数壁面积百分比(wa%)、壁厚外径比(TDR)。结果gOLD3~4级患者wa%_(7~8)、TDR_(7~8)、全肺LAA%_(-950HU)均高于gOLD1~2级(Pwa%_(7~8)、TDR_(7~8)与一秒率(FEV_(1)/FVC)、第一秒用力呼气容积占预计值百分比(FEV_(1)%pre)、用力呼气50%时的瞬间流速(FEF_(50%))、用力呼气75%时的瞬间流速(FEF_(75%))均负相关(Pwa%、TDR可较好预测COPD患者肺功能,对COPD的评估有一定价值。

关键词：慢性阻塞性肺疾病肺气肿小气道肺功能检查三维CT定量参数

Response of Two Jerusalem Artichoke (Helianthus tuberosus)Cultivars Differing in Tolerance to Salt Treatment

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Pedosphere 2010年第4期20卷 515-524页

作者： LONg Xiao-Hua HUANg Zeng-Rong HUANg Yu-Ling KANg Jian ZHANg zhen-Hua LIU Zhao-Pu College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China） Soil Science and Plant Nutrition School of Earth and Environment The University of Western Australia 35 StirlingHighway Crawley WA 6009 （Australia）

To explore genetic variability for two Jerusalem artichoke (Helianthus tuberosus) cultivars, N1 (the sixth-generation cultivated with 75% seawater irrigation for six years) and N7 (a general variety), a experiment was conducted to study the changes in physiological attributes under different concentrations (0%, 10% and 25% of seawater concentration in greenhouse and 0%, 30% and 50% of seawater concentration in the field) of seawater salinity stress. In the greenhouse experiment, decreases of dry growth rate, but increases of dry matter percentage and membrane injury occurred in both the genotypes at 10% and 25% seawater treatments, although lesser cell membrane damage was observed in N1 than N7. N1 accumulated greater contents of Na+, Cl-, soluble sugar and proline in leaves compared with N7. In the field experiment, the yields of shoot, root and tuber, and the contents of total-sugar and inulin in tubers of N1 were higher than those of N7. Lesser degree of salt injury in N1 indicated that the relatively salt-tolerant cultivar had higher K+/Na+ ratio, lower Na+/Ca2+ ratio, and the salt-induced enhancement of osmotic adjustment.

关键词：耐盐品种海水盐度菊芋细胞膜损伤公差反应治疗海水灌溉

Rhenium-osmium(Re-Os)geochronology of crude oil from lacustrine source rocks of the Hailar Basin,NE China

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Petroleum Science 2021年第1期18卷 1-9页

作者： Qi-An Meng Xue wa.g Qiu-Li Huo Zhong-Liang Dong zhen Li Svetlana gTessalina Bryant Dware Brent IAMcInnes Xiao-Lin wa.g Ting Liu Li Zhang Exploration and Development Research Institute Daqing Oilfield Co.Ltd.Daqing 163712HeilongjiangChina Heilongjiang Provincial Key Laboratory for the Study of Tight Oil and Shale Oil Accumulation Daqing 163712HeilongjiangChina John de Laeter Centre Faculty of Science and EngineeringCurtin UniversityGPO Box U1987PerthWA 6485Australia State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023JiangsuChina

Re-Os radiometric dating of crude oil can be used to constrain the timing of hydrocarbon generation,migration or *** approach has been successfully applied to marine petroleum systems;however,this study reports on its application to lacustrine-sourced natural crude *** s amples from multiple wells producing from the Cretaceous Nantun Formation in the Wuerxun-Beier depression of the Hailar Basin in NE China were *** of the Re-Os data are compatible with a Cretaceous hydrocarbon generation event(131.1±8.4 Ma)occurring within 10 Myr of deposition of the Nantun Formation source *** addition,two younger age trends of 54±12 Ma and 1.28±0.69 Ma can be regressed from the Re-Os data,which may reflect the timing of subsequent hydrocarbon generation *** Re-Os geochronometer,when combined with complementary age dating techniques,can provide direct temporal constraints on the evolution of petroleum system in a terrestrial basin.

关键词： Re-Os dating Lacustrine crude oils Hailar basin Petroleum system evolution

广东地区黄羽肉鸡肠杆菌中碳青霉烯耐药基因的流行病学调查

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中国兽医杂志 2023年第4期59卷 19-26页

作者：马振报庞虹许娃丽王建丽丁焕中吴保庆田浪广东海大集团股份有限公司畜牧水产研究中心广东广州511400 华南农业大学兽医学院广东广州510642

为了调查广东地区黄羽肉鸡肠杆菌的耐药性以及碳青霉烯耐药基因的流行病学特征,本研究于2020年8—10月从广东省4个黄羽肉鸡养殖场累计收集的248份样品中分离肠杆菌,利用大肠杆菌基因phoA和细菌16S rRNA进行菌种鉴定,采用琼脂扩散法和微... 详细信息

为了调查广东地区黄羽肉鸡肠杆菌的耐药性以及碳青霉烯耐药基因的流行病学特征,本研究于2020年8—10月从广东省4个黄羽肉鸡养殖场累计收集的248份样品中分离肠杆菌,利用大肠杆菌基因phoA和细菌16S rRNA进行菌种鉴定,采用琼脂扩散法和微量肉汤稀释法测定肠杆菌对13种药物的敏感性,通过PCR方法检测bla_(NDM)、bla_(KPC)、bla_(OXA)和bla_(IMP)四种常见碳青霉烯类耐药基因,并对耐碳青霉烯肠杆菌进行全基因组测序分析,通过接合转移试验探究碳青霉烯耐药基因的水平传播特征。细菌分离和鉴定结果显示,共计分离肠杆菌206株,分离率为83.06%,其中包括186株大肠杆菌、18株肺炎克雷伯菌和2株阴沟肠杆菌。药物敏感性试验结果显示,肠杆菌对氨苄西林钠(94.66%)、复方新诺明(94.66%)、氟苯尼考(86.89%)、盐酸多西环素(70.87%)和硫酸新霉素(61.17%)的耐药性较高,对硫酸阿米卡星(5.83%)、美罗培南(3.40%)和硫酸黏菌素(1.46%)的敏感性较高。PCR结果显示,共有7株肠杆菌检测到碳青霉烯耐药基因,检出率为3.40%,包括5株bla_(NDM-5)基因阳性和2株bla_(OXA-181)基因阳性菌株。全基因组分析结果显示,7株耐碳青霉烯肠杆菌分别为3株大肠杆菌(携带bla_(NDM-5)基因)、2株拟肺炎克雷伯菌(携带bla_(NDM-5)基因)和2株阴沟肠杆菌(携带bla_(OXA-181)基因);7株耐碳青霉烯肠杆菌均携带有大量的耐药基因,且3株大肠杆菌可分为2个序列型(ST)。接合转移试验结果显示,7株耐碳青霉烯菌株均可通过质粒将携带的碳青霉烯耐药基因传播至工程菌C600。结果表明,广东地区黄羽肉鸡肠杆菌耐药状况严峻,耐碳青霉烯基因在肠杆菌的流行率较低,但可通过质粒接合方式发生水平传播,亟需加强监测。

关键词：耐碳青霉烯肠杆菌流行病学黄羽肉鸡耐药性 bla_(NDM-5)基因 bla_(OXA-181)基因

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表没食子儿茶素没食子酸酯纳米化研究进展

食品安全质量检测学报 2023年第6期14卷 255-262页

作者：徐瓦珍刘昌伟王阔飞胡腾飞黄建安刘仲华湖南农业大学茶学教育部重点实验室长沙410128 国家植物功能成分利用工程技术研究中心长沙410128 植物功能成分利用省部共建协同创新中心长沙410128 农业农村部园艺作物基因资源评价利用重点实验室长沙410128

表没食子儿茶素没食子酸酯(epigallocatechin gallate,EgCg)是茶叶中的主要活性成分,具有抗炎、抗氧化等诸多生物活性。然而,体内、体外实验结果与流行病学研究存在较大差异,主要原因是EgCg不稳定、生物利用度低。EgCg口服后只有极少数... 详细信息

表没食子儿茶素没食子酸酯(epigallocatechin gallate,EgCg)是茶叶中的主要活性成分,具有抗炎、抗氧化等诸多生物活性。然而,体内、体外实验结果与流行病学研究存在较大差异,主要原因是EgCg不稳定、生物利用度低。EgCg口服后只有极少数能被肠道所吸收,难以发挥其药理特性。随着科技的发展,科学家们发现纳米化技术能够提高EgCg稳定性,改善EgCg生物利用度。还能够在纳米颗粒上添加靶向分子,使其能定向输送到特定部位,提高EgCg药理特性。纳米化EgCg在食品、医药领域具有广阔前景。碳水化合物、脂质和蛋白质等经过纳米化处理后可以作为包裹EgCg的材料。但是目前关于纳米化EgCg的研究主要集中在体内体外的实验,缺少临床数据支撑,还需要对其安全性和药代动力学等进一步补充和深入研究。因此,本文综述了EgCg吸收、代谢及纳米化EgCg研究进展,以期为EgCg进一步的开发利用提供借鉴。

关键词：纳米包埋表没食子儿茶素没食子酸酯生物利用度抗氧化活性聚合纳米载体