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Cutting Out the Scalpel:A Unique Approach to Vasectomies Interview with Dr.Li Shunqiang,the Originator of No-Scalpel Vasectomy
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《China Population Today》 1995年第Z2期25-27,共3页
CuttingOuttheScalpel:AUniqueApproachtoVasectomiesInterviewwithDr.LiShunqiang,theoriginatorofNo-ScalpelVasect... CuttingOuttheScalpel:AUniqueApproachtoVasectomiesInterviewwithDr.LiShunqiang,theoriginatorofNo-ScalpelVasectomyDr.LiShunqiang... 展开更多
关键词 Origin
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变形监测灰色预测模型对比及替代方法研究
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作者 陈鹏宇 秦岭 《大地测量与地球动力学》 CSCD 北大核心 2024年第4期382-390,共9页
将变形监测灰色预测模型分为传统GM(1,1)模型及其改进模型、非齐次灰色模型、GM(1,1)幂模型及其改进模型3种类型,以Origin拟合函数Exp2PModl、Exponential和SRichards2作为3类灰色预测模型的替代方法,基于理论研究和实例验证对比分析3... 将变形监测灰色预测模型分为传统GM(1,1)模型及其改进模型、非齐次灰色模型、GM(1,1)幂模型及其改进模型3种类型,以Origin拟合函数Exp2PModl、Exponential和SRichards2作为3类灰色预测模型的替代方法,基于理论研究和实例验证对比分析3类灰色预测模型及其替代方法。结果表明,3类灰色预测模型在拟合函数、有无极限值、适合等时距或非等时距建模和适用范围等方面存在显著差异,需要根据变形监测数据特征选择合适的灰色预测模型类别;与3类灰色预测模型相比,Origin拟合函数在参数求解和建模数据要求上更具优势,而且可以得到相当甚至更高的拟合或预测精度,除需要编程实现的特殊优化目标外,完全可以代替灰色预测模型用于变形监测。 展开更多
关键词 变形监测 灰色预测模型 替代方法 Origin拟合函数
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基于ADAMS的烟叶运输车自主校正机构仿真与试验
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作者 杨振纲 陈献勇 +2 位作者 郑仁富 钱勤智 彭宇峰 《福建农机》 2024年第2期18-22,共5页
丘陵山区烟田地形复杂,烟叶运输车在垄沟行驶时方向易发生偏离。针对福建丘陵烟区地形,通过对设计的烟叶运输车自主校正机构进行力学分析,并结合ADAMS仿真对比有自主校正机构与无自主校正机构两种情况下烟叶运输车在垄沟行驶的偏离程度... 丘陵山区烟田地形复杂,烟叶运输车在垄沟行驶时方向易发生偏离。针对福建丘陵烟区地形,通过对设计的烟叶运输车自主校正机构进行力学分析,并结合ADAMS仿真对比有自主校正机构与无自主校正机构两种情况下烟叶运输车在垄沟行驶的偏离程度,仿真结果表明:有自主校正机构的烟叶运输车比无自主校正机构烟叶运输车偏离程度小了10%。最后通过田间试验进一步验证了该机构发挥了自主校正的作用。该研究对丘陵烟田烟叶运输机械的研发具有一定的借鉴参考作用。 展开更多
关键词 烟叶运输 自主校正 ADAMS仿真 Origin数据分析
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利用光电效应实验仪测量液体折射率、电导率
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作者 岳雨星 浦仕然 +4 位作者 蔡芝艳 伊相忠 吕宪魁 郑永刚 刘文广 《大学物理实验》 2024年第3期67-70,105,共5页
以简化实验步骤作为出发点,利用光电效应实验仪测量液体折射率、电导率。结合液体不同物理性质之间的关系,测量同种液体不同浓度时光电流的大小。借助Origin软件拟合光电流与液体折射率、电导率的定标曲线方程。将所测的光电流的大小代... 以简化实验步骤作为出发点,利用光电效应实验仪测量液体折射率、电导率。结合液体不同物理性质之间的关系,测量同种液体不同浓度时光电流的大小。借助Origin软件拟合光电流与液体折射率、电导率的定标曲线方程。将所测的光电流的大小代入即可计算出液体折射率与电导率。 展开更多
关键词 光电效应 折射率 电导率 ORIGIN软件
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Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling 被引量:1
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作者 Shuang-Biao Han Chao-Han Xiang +3 位作者 Xin Du Lin-Feng Xie Jie Huang Cheng-Shan Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期741-751,共11页
The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantl... The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been weak.Based on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different strata.The gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary environment.With increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to inorganic.The origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and mantle-derived.The shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic gas.Furthermore,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived gas.The discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas. 展开更多
关键词 Gas compositions Stable isotopes Gas origins Hydrogen gas Songliao Basin
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Genetic dissection and origin of pleiotropic loci underlying multilevel fiber quality traits in upland cotton(Gossypium hirsutum L.) 被引量:1
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作者 Hongge Li Shurong Tang +7 位作者 Zhen Peng Guoyong Fu Yinhua Jia Shoujun Wei Baojun Chen Muhammad Shahid Iqbal Shoupu He Xiongming Du 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3250-3263,共14页
Cotton fiber quality is a persistent concern that determines planting benefits and the quality of finished textile products.However,the limitations of measurement instruments have hindered the accurate evaluation of s... Cotton fiber quality is a persistent concern that determines planting benefits and the quality of finished textile products.However,the limitations of measurement instruments have hindered the accurate evaluation of some important fiber characteristics such as fiber maturity,fineness,and neps,which in turn has impeded the genetic improvement and industrial utilization of cotton fiber.Here,12 single fiber quality traits were measured using Advanced Fiber Information System(AFIS)equipment among 383 accessions of upland cotton(Gossypium hirsutum L.).In addition,eight conventional fiber quality traits were assessed by the High Volume Instrument(HVI)System.Genome-wide association study(GWAS),linkage disequilibrium(LD)block genotyping and functional identification were conducted sequentially to uncover the associated elite loci and candidate genes of fiber quality traits.As a result,the previously reported pleiotropic locus FL_D11 regulating fiber length-related traits was identified in this study.More importantly,three novel pleiotropic loci(FM_A03,FF_A05,and FN_A07)regulating fiber maturity,fineness and neps,respectively,were detected based on AFIS traits.Numerous highly promising candidate genes were screened out by integrating RNA-seq and qRT-PCR analyses,including the reported GhKRP6 for fiber length,the newly identified GhMAP8 for maturity and GhDFR for fineness.The origin and evolutionary analysis of pleiotropic loci indicated that the selection pressure on FL_D11,FM_A03 and FF_A05 increased as the breeding period approached the present and the origins of FM_A03 and FF_A05 were traced back to cotton landraces.These findings reveal the genetic basis underlying fiber quality and provide insight into the genetic improvement and textile utilization of fiber in G.hirsutum. 展开更多
关键词 upland cotton single fiber quality pleiotropic loci candidate genes locus origin
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基于Origin的土遗址防雨水侵蚀调控机理研究——以晋阳古城西城墙为例
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作者 尚瑞华 韩鹏举 +3 位作者 谷瑞芳 程驰 吴雅娟 刘伟伟 《太原理工大学学报》 CAS 北大核心 2024年第4期686-695,共10页
【目的】通过Origin软件分析,了解晋阳古城西城墙裸土土遗址与草本植物覆盖土遗址的防雨水侵蚀机理及最终效果。【方法】通过Origin软件分析原位人工模拟降雨实验数据的方法,对比植物生长状况对土遗址坡面产流、产沙效果的影响作用。【... 【目的】通过Origin软件分析,了解晋阳古城西城墙裸土土遗址与草本植物覆盖土遗址的防雨水侵蚀机理及最终效果。【方法】通过Origin软件分析原位人工模拟降雨实验数据的方法,对比植物生长状况对土遗址坡面产流、产沙效果的影响作用。【结果】产流前降雨截留量Q_(0)与新生草产流起始时间T_(0)呈负相关,且Q_(0)遵循枯草>新生草>裸土;新生草产沙系数C_(sy)、产沙强度I_(sy)与降雨强度呈显著正相关,产流、产沙效果遵循规律为裸土>枯草>新生草;裸露土遗址通过形成泥皮面层的方式,保证土体内部少受雨水浸润,适用于干旱气候区;草本植物通过强化土遗址抗冲性,减少土体表面冲刷,适用于半干旱半湿润气候区。【结论】Origin软件分析证实,草本植物提高土遗址抗冲性效果显著,草本植物覆盖土遗址现象利于山西本地土遗址保护,但当极端持续强降雨发生在9-10月间时,草本植物覆盖土遗址是否适用仍待继续研究。 展开更多
关键词 ORIGIN软件 土遗址 强降雨 侵蚀 雨水 草本
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Origin软件在大学物理实验教学中的应用
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作者 刘念 左绪忠 +2 位作者 何恩节 秦炎福 官邦贵 《科技风》 2024年第26期124-126,共3页
Origin软件强大的数据处理及绘图能力有助于学生在大学物理实验中对数据进行分析、拟合和图像的绘制。以霍尔效应法测电螺线管轴向磁感应强度实验为例,介绍Origin软件的数据处理及拟合功能。结果表明,Origin软件的应用有效地提升了学生... Origin软件强大的数据处理及绘图能力有助于学生在大学物理实验中对数据进行分析、拟合和图像的绘制。以霍尔效应法测电螺线管轴向磁感应强度实验为例,介绍Origin软件的数据处理及拟合功能。结果表明,Origin软件的应用有效地提升了学生的绘图水平,降低了绘图误差,也为学生未来的学习和科研打下坚实的基础。 展开更多
关键词 ORIGIN 大学物理实验 霍尔效应 数据拟合
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基于“互联网+”职业教育学生学习行为的探讨
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作者 董志辉 闫云敬 +2 位作者 杨永贵 朱炳耀 韩立星 《汽车与驾驶维修》 2024年第5期77-80,共4页
本文以柳州城市职业学院汽车检测与维修专业学生为研究对象,通过“互联网+”环境下的在线学习数据,采用Excel和Origin软件进行数理统计分析,以探讨学生的学习行为如何影响学习效果。研究结果表明:学生在学期开始阶段的学习投入程度较高... 本文以柳州城市职业学院汽车检测与维修专业学生为研究对象,通过“互联网+”环境下的在线学习数据,采用Excel和Origin软件进行数理统计分析,以探讨学生的学习行为如何影响学习效果。研究结果表明:学生在学期开始阶段的学习投入程度较高,学习效果相对较高好;但在后续阶段则更多关注完成课后作业,而对学习的深层意义和持续投入有所忽视,并没有达到预期学习效果。根据数理统计分析得到的研究结果,并剖析问题结论,本文提出了改进在线课程设计、优化考核方式、加强在线学习监督与引导以及提供丰富的学习资源等教学改进建议。 展开更多
关键词 互联网+ 职业教育 学习行为 EXCEL ORIGIN
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多函数模型拟合表面张力与浓度曲线的比较
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作者 韩瑞麟 阎晓琦 《大学化学》 CAS 2024年第7期381-385,共5页
为了更深入地研究表面张力的经典实验,利用Origin软件,采用多种函数模型对表面张力与浓度曲线分别进行拟合,并对每种函数拟合的优缺点加以讨论。其中对数函数拟合数学准确性较高,同时兼具物理意义,更贴切实况。明确了表面张力与浓度拟... 为了更深入地研究表面张力的经典实验,利用Origin软件,采用多种函数模型对表面张力与浓度曲线分别进行拟合,并对每种函数拟合的优缺点加以讨论。其中对数函数拟合数学准确性较高,同时兼具物理意义,更贴切实况。明确了表面张力与浓度拟合的经典实验中以对数函数模型最为适宜。 展开更多
关键词 多函数模型 表面张力 物理化学实验 非线性拟合 ORIGIN软件
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Origin软件在声速的测量实验数据处理中的应用
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作者 杨波 邢海波 王晨辰 《大学物理实验》 2024年第4期86-88,共3页
以大学物理实验中声速的测量为例,利用了Origin软件对实验测量所得的数据进行了线性拟合,并和传统的逐差法计算结果进行了比较,两种方法所得出的声速大小几乎吻合。结果表明,在实验教学中引入Origin软件对实验数据进行处理,操作更为方... 以大学物理实验中声速的测量为例,利用了Origin软件对实验测量所得的数据进行了线性拟合,并和传统的逐差法计算结果进行了比较,两种方法所得出的声速大小几乎吻合。结果表明,在实验教学中引入Origin软件对实验数据进行处理,操作更为方便快捷,并且能够有效提高实验效率和实验准确率,避免人为因素带来的误差。 展开更多
关键词 ORIGIN软件 声速的测量 逐差法 数据处理
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Origin软件在“微生物学”实验教学中的应用——以细菌生长曲线的测定实验为例
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作者 郭佳 唐雅丽 +1 位作者 雷腊梅 许德麟 《教育教学论坛》 2024年第11期21-24,共4页
针对高校本科“微生物学”实验教学中遇到的数据处理问题,以细菌生长曲线测定的实验为例,使用Origin 2022软件进行数据导入、数据计算、图形绘制及插入误差棒等操作,完成细菌生长曲线的绘制。结果表明,利用Origin软件可以快速对实验数... 针对高校本科“微生物学”实验教学中遇到的数据处理问题,以细菌生长曲线测定的实验为例,使用Origin 2022软件进行数据导入、数据计算、图形绘制及插入误差棒等操作,完成细菌生长曲线的绘制。结果表明,利用Origin软件可以快速对实验数据进行批量处理,操作简捷并可避免人工计算的误差,对实验得到的非线性数据通过软件可以拟合出美观的图形,将实验结果可视化。在教学中通过引入Origin软件,可以在讲授具体微生物知识的同时,让本科生掌握一款专业的数据分析处理软件,有助于培养本科生的数据处理能力,提高综合科研素养,为后续实验课程和科研工作的数据处理工作打好基础。 展开更多
关键词 微生物学实验 ORIGIN 数据处理 生长曲线 实验教学改革
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Identification of S-RNase genotype and analysis of its origin and evolutionary patterns in Malus plants
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作者 Zhao Liu Yuan Gao +10 位作者 Kun Wang Jianrong Feng Simiao Sun Xiang Lu Lin Wang Wen Tian Guangyi Wang Zichen Li Qingshan Li Lianwen Li Dajiang Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1205-1221,共17页
Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibili... Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibility in Malus plants.In this experiment,88 Malus germplasm resources,such as Aihuahong,Xishuhaitang,and Reguanzi,were used as materials.Seven gene-specific primer combinations were used in the genotype identification.PCR amplification using leaf DNA produced a single S-RNase gene fragment in all materials.The results revealed that 70 of the identified materials obtained a complete S-RNase genotype,while only one S-RNase gene was found in 18 of them.Through homology comparison and analysis,13 S-RNase genotypes were obtained:S_(1)S_(2)(Aihuahong,etc.),S_(1)S_(28)(Xixian Haitang,etc.),S_(1)S_(51)(Hebei Pingdinghaitang),S_(1)S_(3)(Xiangyangcun Daguo,etc.),S_(2)S_(3)(Zhaiyehaitang,etc.),S_(3)S_(51)(Xishan 1),S_(3)S_(28)(Huangselihaerde,etc.),S_(2)S_(28)(Honghaitang,etc.),S_(4)S_(28)(Bo 11),S_(7)S_(28)(Jiuquan Shaguo),S_(10)S_e(Dongchengguan 13),S_(10)S_(21)(Dongxiangjiao)and S_(3)S_(51)(Xiongyue Haitang).Simultaneously,the frequency of the S gene in the tested materials was analyzed.The findings revealed that different S genes had varying frequencies in Malus resources,as well as varying frequencies between intraspecific and interspecific.S_(3) had the highest frequency of 68.18%,followed by S_(1)(42.04%).In addition,the phylogenetic tree and origin evolution analysis revealed that the S gene differentiation was completed prior to the formation of various apple species,that cultivated species also evolved new S genes,and that the S_(50) gene is the oldest S allele in Malus plants.The S_(1),S_(29),and S_(33) genes in apple-cultivated species,on the other hand,may have originated in M.sieversii,M.hupehensis,and M.kansuensis,respectively.In addition to M.sieversii,M.kansuensis and M.sikkimensis may have also played a role in the origin and evolution of some Chinese apples. 展开更多
关键词 MALUS S-RNase genotype SELF-INCOMPATIBILITY origin and evolution
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Interpretation of the Standards of Basic Dataset of Chronic Diseases Behavior Risk Factor Surveillance in Adults
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作者 ZHAO Yan Fang ZHANG Mei +3 位作者 WEI Wen Qiang SUN Ke Xin LI Xin Hua WANG Li Min 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第5期551-556,共6页
BACKGROUND China’s Behavioral Risk Factor Surveillance System(BRFSS)originated from the World Bankfunded HealthⅦLoan Project in the 1990s,which conducted behavioral risk factor surveillance in seven cities and one p... BACKGROUND China’s Behavioral Risk Factor Surveillance System(BRFSS)originated from the World Bankfunded HealthⅦLoan Project in the 1990s,which conducted behavioral risk factor surveillance in seven cities and one province^([1]).Drawing on the World Health Organization’s(WHO)STEPwise approach to surveillance(STEPs)and the U.S.Behavioral Risk Factor Surveillance System(BRFSS)^([2,3]). 展开更多
关键词 funded Basic originated
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Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities
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作者 Bing-Kun Meng Dao-Fu Song +1 位作者 Yuan Chen Sheng-Bao Shi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期777-790,共14页
A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dim... A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude oils.Based on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient sediments.Oil samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter input.It should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments. 展开更多
关键词 1 2 4 5-Tetramethylbenzene GC×GC-TOFMS Organic matter origin Depositional environment
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Space Rocks-and Dust-Roll into Planetary Science Limelight
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作者 Sean O’Neill 《Engineering》 SCIE EI CAS CSCD 2024年第8期3-6,共4页
Space sample retrieval is having a moment.On 24 September 2023,in a triumph of complex engineering,a US National Aeronau-tics and Space Administration(NASA)mission,OSIRUS-REx(short for origins,spectral interpretation,... Space sample retrieval is having a moment.On 24 September 2023,in a triumph of complex engineering,a US National Aeronau-tics and Space Administration(NASA)mission,OSIRUS-REx(short for origins,spectral interpretation,resource identification,and security-regolith explorer;regolith is the surface layer of uncon-solidated rocks and dust/soil covering bedrock),successfully deliv-ered to Earth a capsule containing the largest sample of asteroid material ever collected,captured from Bennu. 展开更多
关键词 ROCK EARTH ORIGIN
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Geographical origin identification of winter jujube(Ziziphus jujuba Dongzao')by using multi-element fingerprinting with chemometrics
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作者 Xiabing Kong Qiusheng Chen +8 位作者 Min Xu Yihui Liu Xiaoming Li Lingxi Han Qiang Zhang Haoliang Wan Lu Liu Xubo Zhao Jiyun Nie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1749-1762,共14页
Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 16... Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits. 展开更多
关键词 winter jujube multi-element fingerprint analysis CHEMOMETRICS origin traceability
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Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H
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作者 Jianzhao Yin Yuhong Chao +2 位作者 Haoyu Yin Hongyun Shi Shoupu Xiang 《Acta Geochimica》 EI CAS CSCD 2024年第2期385-398,共14页
By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)... By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly magmatic.According to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will be.In other words,mantle-derived solutions can have extremely low hydrogen isotope values.This means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the deposit.The formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma. 展开更多
关键词 Carbon oxygen and hydrogen isotopes ORIGIN Independent tellurium deposit The Qinghai–Xizang Plateau
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Modifications in aroma characteristics of'Merlot'dry red wines aged in American,French and Slovakian oak barrels with different toasting degrees
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作者 Haocheng Lu Binhao Cheng +2 位作者 Yibin Lan Changqing Duan Fei He 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期381-391,共11页
Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to wines.In the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermen... Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to wines.In the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermented in two types of fermenters(stainless steel tank and rotated oak barrel)and aged in six types of oak barrels(three geographic origins×two toasting degrees)for different time(0,3,6 and 9 months,respectively).Results showed that 30 volatiles were associated with barrels and increased during oak aging.The fermenters could influence the intensities of the toast,leathery,smoky,fruity,floral and caramel aromas.The concentration of whisky lactone,eugenol,cis-isoeugenol,and the intensities of the toast and spicy aromas were highest in the wines aged in American oak and were lowest in the wines aged in French oak barrels.The concentrations of guaiacol,syringol,trans-isoeugenol,furfural alcohol,vanilla,cis-whisky lactone enabled the medium toasting barrels to be distinguished from the light toasting ones.The compounds originating from the barrels could be used to distinguish the types of different barrels,but the other general grape-derived and fermentation-derived volatiles could not.The fermenters,oak species and toasting degrees of the barrels all had significant effects on the aroma profiles of the aged‘Merlot’dry red wines,but the influence of the geographic origin was not obvious. 展开更多
关键词 Wine Aroma Oak Barrel Oak species Toasting degrees Geographic origin Aging
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A plausible pathway to prebiotic peptides via amino acid amides on the primordial Earth
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作者 DingWei Gan XiangMin Lei +6 位作者 RenWu Zhou SongSen Fu Jing Sun RuSen Zhou Kostya(Ken)Ostrikov YuFen Zhao JianXi Ying 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期868-877,共10页
The prebiotic synthesis of peptides prior to ribosome-catalyzed processes remains an enigma.The synthesis of abiotic peptides from amino acids(AAs)is primarily constrained by high activation energies and unfavorable t... The prebiotic synthesis of peptides prior to ribosome-catalyzed processes remains an enigma.The synthesis of abiotic peptides from amino acids(AAs)is primarily constrained by high activation energies and unfavorable thermodynamics,necessitating the identification of plausible prebiotic alternatives for synthesizing prebiotic peptides.Here we present a plausible pathway to the formation of prebiotic peptides,wherein oligopeptides,oligopeptide amides,and cyclic oligopeptides can be directly synthesized from amino acid amides(AA-NH2)under wet–dry cycle conditions without the need for any enhancers.The subsequent investigation revealed that AA-NH2 demonstrated more favorable thermodynamic reaction effects than AAs in peptide formation.In contrast to the polymerization of AAs,the process of peptide formation through the polymerization of AA-NH2 was significantly simplified.Additionally,AA-NH2 was discovered to function as a“bridge”for the formation of peptides from AAs,thereby facilitating their participation in the synthesis of intricate peptide structures.On the basis of these findings,a plausible mechanism for the prebiotic origin network of peptides under primordial Earth conditions has been proposed.Overall,this research presents a plausible pathway for the generation of prebiotic peptides and peptide libraries within prebiotic environments. 展开更多
关键词 prebiotic chemistry origin of life chemical evolution PEPTIDE
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