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1The origin, transmission and clinical therapies on coronavirus disease 2019(COVID-19) outbreak——an update on the status显示文摘An acute respiratory disease,caused by a novel coronavirus(SARS-CoV-2,previously known as 2019-nCoV),the coronavirus disease 2019(COVID-19)has spread throughout China and received worldwide attention.On 30 January 2020,World Health Organization(WHO)officially declared the COVID-19 epidemic as a public health emergency of international concern.The emergence of SARS-CoV-2,since the severe acute respiratory syndrome coronavirus(SARSCoV)in 2002 and Middle East respiratory syndrome coronavirus(MERS-CoV)in 2012,marked the third introduction of a highly pathogenic and large-scale epidemic coronavirus into the human population in the twenty-first century.As of 1 March 2020,a total of 87,137 confirmed cases globally,79,968 confirmed in China and 7169 outside of China,with 2977 deaths(3.4%)had been reported by WHO.Meanwhile,several independent research groups have identified that SARS-CoV-2 belongs toβ-coronavirus,with highly identical genome to bat coronavirus,pointing to bat as the natural host.The novel coronavirus uses the same receptor,angiotensin-converting enzyme 2(ACE2)as that for SARS-CoV,and mainly spreads through the respiratory tract.Importantly,increasingly evidence showed sustained human-tohuman transmission,along with many exported cases across the globe.The clinical symptoms of COVID-19 patients include fever,cough,fatigue and a small population of patients appeared gastrointestinal infection symptoms.The elderly and people with underlying diseases are susceptible to infection and prone to serious outcomes,which may be associated with acute respiratory distress syndrome(ARDS)and cytokine storm.Currently,there are few specific antiviral strategies,but several potent candidates of antivirals and repurposed drugs are under urgent investigation.In this review,we summarized the latest research progress of the epidemiology,pathogenesis,and clinical characteristics of COVID-19,and discussed the current treatment and scientific advancements to combat the epidemic novel coronavirus.Yan-Rong Guo Qing-Dong Cao Zhong-Si Hong Yuan-Yang Tan Shou-Deng Chen Hong-Jun Jin Kai-Sen Tan De-Yun Wang Yan Yan 2020Military Medical Research2020,7,1:123
2城市地下综合管廊火灾烟气温度场研究显示文摘为研究综合管廊电力舱室内火灾初期温度场特征,建立1∶3.6小尺寸综合管廊模型,通过改变盛放汽油盘的大小改变火源功率,进行油池火火灾实验。运用Origin软件对温度数据进行分析,得到烟气温度与距离的衰减经验公式;运用FDS软件对与实验相同工况下的几何模型进行计算机模拟,以验证FDS模拟结果准确性。实验结果表明:不同火源功率下,烟气温度均呈现幂函数衰减;火源功率较大时,温度衰减梯度也较大;对距火源0.3m处垂直方向上烟气温度进行分析得知,火灾烟气蔓延过程中存在烟气分层现象。通过FDS模拟结果与实验结果对比,得出两者结果较为相近。赵永昌 朱国庆 高云骥 2017消防科学与技术2017,36,1:62
3贺兰山孔兹岩系的变质时代及其对华北克拉通西部陆块演化的制约显示文摘贺兰山孔兹岩系作为华北克拉通西部孔兹岩带的重要组成部分,其变质时代问题一直悬而未决。利用SHRIMP锆石U-Pb定年技术,对贺兰山孔兹岩系中3个代表性富铝片麻岩(石榴堇青钾长片麻岩、石榴堇青二长片麻岩与石榴黑云斜长片麻岩)样品进行了精确定年。发现这3种岩石虽处不同层位,但其碎屑锆石年龄却非常集中,各测点^(207)Pb/^(206)Pb年龄总体变化在2.0~2.1Ga之间,加权平均年龄则在2017~2040Ma之间。这些碎屑锆石都具有岩浆结构特征,反映当时曾存在大规模花岗质岩浆活动,所成岩体为孔兹岩系沉积提供了充足物源。另有少量大于2.5Ga的碎屑锆石(2520~2949Ma),表明本区存在太古代岩浆活动记录。本区石榴堇青二长片麻岩中发育典型的变质增生锆石,其成因很可能与黑云母的脱水熔融反应有关。利用该锆石确定贺兰山孔兹岩系的变质时代为1950±8Ma。该时代与东部大青山、乌拉山孔兹岩系变质时代相同,表明华北克拉通西部的阴山地块与鄂尔多斯地块大体是以平行的方式正面拼贴到一起的。周喜文 耿元生 2009岩石学报2009,25,8:55
4Origin在曲线拟合中的应用显示文摘论文给出了用Origin进行数据分析的方法,结合VisualBasic编程得到了较为理想的曲线拟合结果。实验表明该方法操作简单,精确度高,具有一定的实用价值。武新 张永胜 2005计算机工程与应用2005,41,17:42
5塔里木盆地塔北东部下奥陶统基质白云岩的稀土元素特征及其成因显示文摘白云岩成因机制的核心问题之一是白云石化流体的来源。本文选择塔北东部地区下奥陶统蓬莱坝组白云岩、云质灰岩作为研究对象,在沉积学和岩石学基础上对基质白云岩的稀土元素地球化学特征进行了分析研究。结果表明,白云岩、云质灰岩中Sc、Th、Hf、Zr等元素的含量远远低于这些元素在陆源沉积物中的含量,并且Th、Zr的含量与Y/Ho比值间不具有明显的正相关关系,La的正异常、较高的Y/Ho比值等特征均表明塔北东部下奥陶统蓬莱坝组碳酸盐岩形成的环境为未受陆源物质混染的浅海相沉积。而白云岩负Ce异常、正La异常、轻微富集的Gd正异常以及La正异常与Y异常的正相关性等典型稀土元素特征均反映了白云石化流体具有典型的海水来源特征;而基质白云岩与白云质灰岩之间的∑REE+Y,∑LREE和∑HREE含量差异表明,在白云石化过程中稀土元素发生了一定程度的流失,且HREE较之于LREE更易于发生流失,因此白云石化过程中成岩流体对HREE的移出量大于LREE的移出量是塔北东部下奥陶统白云岩具有相对富集的LREE及相对较低的Y/Ho比值的主要原因。结合岩石学、沉积学、微量元素以及稳定同位素特征的综合分析认为,塔北东部地区下奥陶统蓬莱坝组基质白云岩是海水白云石化作用的结果。个别白云岩样品的Eu正异常以及同层位构造裂隙方解石的δ^(18)O、^(87)Sr/^(86)Sr以及流体包裹体均表明下奥陶统蓬莱坝组受到后期热液流体的影响,但其对研究样品基质白云岩的影响程度比较弱。韩银学 李忠 韩登林 彭守涛 刘嘉庆 2009岩石学报2009,25,10:43
6锡林浩特杂岩和蓝片岩的锆石U-Pb年代学及其对索仑缝合带演化的意义显示文摘报道了内蒙索仑缝合带附近的锡林浩特杂岩和苏左旗混杂带中蓝片岩块的锆石U-Pb年代学数据。锡林浩特杂岩中碎屑锆石来源复杂,从晚太古至晚古生代均有。最年轻的碎屑锆石U-Pb年龄为280~340Ma,与该区最年轻的弧岩浆岩年龄一致,表明该杂岩的原岩最终形成于晚古生代,而不是前寒武陆块残留。锡林浩特杂岩原岩的沉积源区主要是古生代的弧岩浆岩和部分裸露的前寒武陆壳,可能是弧前沉积建造。蓝片岩的锆石U-Pb年龄为318±5Ma(范围338~280Ma),这些锆石显示典型岩浆振荡环带结构,因此该年龄可能代表其原岩形成年龄,而其变质应该在280Ma之后。所以,锡林浩特杂岩和混杂带中蓝片岩块的变质变形作用可能发生在晚二叠,与索仑缝合带强烈的孤陆碰撞有关,暗示索仑缝合带的碰撞缝合时间在晚二叠,而不是许多人坚持的泥盆纪。陈斌 马星华 刘安坤 木合塔尔·扎日 2009岩石学报2009,25,12:47
7Two new ornithurine birds from the Early Cretaceous of western Liaoning,China显示文摘We describe two new ornithurine birds from the Early Cretaceous Jiufotang Formation of western Liaoning, northeast China: Yanornis martini gen. et sp. nov. and Yixianornis grabaui gen. et sp. nov. They represent the best fossil record of ornithurine birds known from the Early Cretaceous. They are more advanced than the most primitive ornithurine Liaoningornis, and are more similar to the other two Chinese Early Cretaceous ornithurines Chaoyangia and Songlingornis. Compared with Confuciusornis, Liaoxiornls and Eoenantiornis from the same age, the two new birds show remarkable advanced characteristics and suggest the presence of powerful flight capability like modern birds. Compared with Yixianornis and Chaoyangia, Yanornis is larger, with a more elongated skull and relatively long wings. The new discoveries indicate that by the Early Cretaceous both enantiornithine and ornithurine birds had already radiated significantly. The flight structures of Yanornis and Yixianornis are hardly distinguishable fromZhonghe Zhou Fucheng Zhang 2001Chinese Science Bulletin2001,46,15:36
8肖维勒准则和格拉布斯准则的比较显示文摘目前大多物理实验工作者剔除实验异常数据时,多选择肖维勒准则作为判断工具。但肖维勒准则具有概率分布不均匀的缺点,对异常数据的剔除存在误判的可能性。以《测直流电源的电动势和内阻》为例,利用Origin软件进行实验数据的线性拟合以及调用程序编辑功能,实现肖维勒准则和格拉布斯准则对异常数据的判断和剔除。根据两个剔除结果的差异,结合实验数据的特点,从实验数据的测量次数和剔除原则的显著水平两个角度来比较两个剔除准则。提出应根据实验次数和实验要求来选择异常数据剔除准则。林丽芬 肖化 吴先球 2012大学物理实验2012,25,6:38
9Origin8.0在物理实验数据处理中的应用显示文摘结合具体的物理实验,系统的介绍了用Origin8.0软件进行实验数据统计分析、数据绘图等方法,全面的呈现了Origin软件在物理实验数据处理中的各种应用。吴林涛 张军朋 2012大学物理实验2012,25,1:27
10基于视频分析软件Tracker测量刚体转动惯量显示文摘在传统刚体转动惯量实验仪器的基础上,用弹簧代替砝码,用手机拍摄实验过程,用Tracker和Origin软件处理实验数据,来研究刚体转动惯量.考虑加速度、摩擦力矩等因素的影响后,系统误差减少,并实验测量了摩擦力矩.贾昱 程敏熙 安盟 王经淘 李荣妹 2014物理实验2014,34,5:24
11潘谢矿区导水裂隙带发育高度与采厚关系回归分析显示文摘根据淮南潘谢矿区最近几年导水裂隙带的实测资料,使用功能强大的数学分析软件Origin对其导水裂隙带与采厚关系进行数学回归分析,并对照现有规范中的关系通式,总结出更适合淮南矿区的预测公式,为以后淮南矿区防水煤柱的留设提供更可靠的理论依据。李洋 李文平 刘登宪 2005地球与环境2005,33,B10:23
12Natural gas origins of large and medium-scale gas fields in China sedimentary basins显示文摘China sedimentary basins present abundant natural gas resource thanks to its unique geological settings.Marine highly-matured hydrocarbon source rocks,widespread coal-measure strata and low temperature Quaternary saline strata,etc.,indicate the wide foreground of China natural gas resources. Up to now,most of the petroliferous basins have been discovered to have wholesale natural gas accumulation from Precambrian,Paleozoic,Mesozoic to Cenozoic in the east,the central,the west and the coast of China.These large and medium-scale gas reservoirs are mainly composed of hydrocarbon gas with big dry coefficient,tiny non-hydrocarbon,wide carbon isotope distribution and varying origin types,the hydrocarbon gas includes coal-formed gas,oil-formed gas,biogenic gas and inorganic gas, etc.Coal-formed gas is the main type of China natural gas resources,in particular several explored large-scale gas fields(>100 billion cubic meter)of Kela 2,Sulige and Daniudi,etc.,they all belong to coal-formed gas fields or the gas fields consisting mostly of coal-formed gas.Oil-formed gas is also abundant in China marine basins,for example marine natural gas of Sichuan Basin generated from crude oil cracking gas.Primary and secondary biogenic gas fields were discovered respectively in the Qaidam Basin and Western Slope of Songliao Basin.In addition,inorganic gases are mainly distributed in the eastern China,in particular the Songliao Basin with abundant carbon dioxide accumulation,indicating that the eastern China present large exploration potential of inorganic gas.ZHANG ShuiChang &ZHU GuangYou Research Center of Research Institutes of PetroChina Exploration and Development,Beijing 100083,China 2008Science China Earth Sciences2008,51,S1:21
13Origin of gray-green sandstone in ore bed of sandstone type uranium deposit in north Ordos Basin显示文摘Dongsheng sandstone-type uranium deposit is located in the northern part of Ordos Basin, occurring in the transitional zones between gray-green and gray sandstones of Jurassic Zhiluo Formation. Sandstones in oxidized zone of the ore bed look gray-green, being of unique signature and different from one of ordinary inter-layered oxidation zone of sandstone-type uranium deposits. The character and origin of gray-green sandstones are systematically studied through their petrology, mineralogy and geochemistry. It is pointed out that this color of sandstones is originated from secondary oil-gas reduction processes after paleo-oxidation, being due to acicular-leaf chlorite covering surfaces of the sandstone grains. To find out the origin of gray-green sandstone and recognize paleo-oxidation zones in the ore bed are of not only theoretical significance for understanding metallogenesis of this kind of sandstone-type uranium deposit, but also very importantly practical significance for prospecting for similar kind of sandstone-type uranium deposit.LI ZiYing FANG XiHeng CHEN AnPing OU GuangXi XIAO XinJian SUN Ye LIU ChiYang WANG Yi 2007Science China Earth Sciences2007,50,z2:20
14基于Origin软件正确评定韧脆性转变温度显示文摘采用Boltzmann函数描述冲击功与温度的关系曲线,介绍了基于Origin软件评定韧脆转变温度的方法,示例讨论说明该方法简便正确、精度高,可作为实验室冲击试验数据分析的工具。罗晓蓉 陈晨枫 丁欲晓 徐炜新 2010物理测试2010,28,2:20
15利用Origin软件对大学物理实验数据进行曲线分析的两个实例显示文摘通过两个具体的实验例子介绍Origin软件对数据曲线进行分析的一些功能,以便更好地运用Origin软件于大学物理实验数据曲线分析中。李锦文 吴先球 熊建文 2010大学物理实验2010,23,5:17
16Dual origins of Xiaoqinling gold-bearing quartz veins:Fluid inclusion evidence显示文摘Fluid inclusion research in Archean metamorphic rocks, Yanshanian granite and gold-bearing quartz veins shows that regional metamorphic fluids are high temperature and high saline, Yanshanian post-granitic fluids are CO2-bearing low saline, and ore-forming fluids are also CO2-rich low saline. In gold-barren/free parts of quartz veins in gold deposits, daughter mineral-bearing high saline inclusions related with metamorphic fluids remained. This proclaims quartz veins hosting gold ores might have been formed in early metamorphism, and overlapped or mineralized by late Yanshanian gold-bearing fluids.Hongrui Fan Yihan Xie Rui Zhao Yinglan Wang 2000Chinese Science Bulletin2000,45,15:17
17使用Origin7.0软件处理物理实验数据显示文摘用Origin7.0软件对物理实验数进行绘图处理,简单易行.滕坚 2006物理与工程2006,16,2:16
18基于Origin的波动光学实验仿真显示文摘以光的干涉、衍射实验为例,介绍利用Origin软件实现光学实验仿真的方法.该方法避免了复杂的编程,易学易用,实现过程简便.其逼真的仿真图样与光强分布曲线,为光学的理论分析与实验教学提供便利,可以引导学生开展探究性学习,加深对光学现象和规律的理解,从而提高教学质量.曹卫军 赖康荣 2015大学物理2015,34,1:16
19重要应用化学软件和数据库导论显示文摘重点介绍著名免费应用化学专业软件和数据库的主要功能和使用方法。简介一些重要商业版应用化学专业软件的特点。通过本文可以看到现代应用化学专业软件的最新发展动态和水准。庞晓红 2005计算机与应用化学2005,22,3:16
20Characterization of mitochondrial genome of Chinese wild mulberry silkworm, Bomyx mandarina(Lepidoptera:Bombycidae)显示文摘The complete mitochondrial genome of Chinese Bombyx mandarina(ChBm) was determined.The cir-cular genome is 15682 bp long, and contains a typical gene complement, order, and arrangement iden-tical to that of Bombyx mori(B.mori) and Japanese Bombyx mandarina(JaBm) except for two addi-tional tRNA-like structures:tRNASer(TGA)-like and tRNAIle(TAT)-like.All protein-coding sequences are initi-ated with a typical ATN codon except for the COI gene, which has a 4-bp TTAG putative initiator codon.Eleven of 13 protein-coding genes(PCGs) have a complete termination codon(all TAA), but the re-maining two genes terminate with incomplete codons.All tRNAs have the typical clover-leaf structures of mitochondrial tRNAs, with the exception of tRNASer(TGA)-like, with a four stem-and-loop structure.The length of the A+T-rich region of ChBm is 484 bp, shorter than those of JaBm(747 bp) and B.mori(494―499 bp).Phylogenetic analysis among B.mori, ChBm, JaBm, and Antheraea pernyi(Anpe) showed that B.mori is more closely related to ChBm than JaBm.The earliest divergence time estimate for B.mori-ChBm and B.mori-JaBm is about 1.08±0.18―1.41±0.24 and 1.53±0.20―2.01±0.26 Mya, respec-tively.ChBm and JaBm diverged around 1.11±0.16―1.45±0.21 Mya.PAN MinHui1, YU QuanYou1, XIA YuLing1, DAI FangYin1, LIU YanQun2, LU Cheng1, ZHANG Ze1 & XIANG ZhongHuai1 1 Key Sericultural Laboratory of Agricultural Ministry, Southwest University, Chongqing 400716, China 2 College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang 110161, China 2008Science China(Life Sciences)2008,51,8:16
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