期刊文献+
共找到2,721篇文章
< 1 2 137 >
每页显示 20 50 100
纺织品干燥速率计算方法分析与研究
1
作者 穆奎 唐孔科 +1 位作者 肖凤娟 李娅菲 《针织工业》 北大核心 2026年第1期82-84,共3页
利用最小二乘法拟合线性方程的斜率求干燥速率,数据点的选取主要依靠检测人员的主观判断,不同的检测人员选取的数据点不一样,检测结果也不一样。利用Origin软件拟合时间-蒸发量函数曲线,通过函数拟合相关系数R值判断函数曲线与水分蒸发... 利用最小二乘法拟合线性方程的斜率求干燥速率,数据点的选取主要依靠检测人员的主观判断,不同的检测人员选取的数据点不一样,检测结果也不一样。利用Origin软件拟合时间-蒸发量函数曲线,通过函数拟合相关系数R值判断函数曲线与水分蒸发趋势的符合程度,以拟合曲线切线的最大斜率为干燥速率,消除了因不同试验人员选取数据点不同而造成的结果差异。通过比对仪器方法、Origin软件测试方法和标准测试方法的检测结果,Origin软件测试方法能够快速绘制反映水分蒸发趋势的时间-蒸发量曲线和准确计算干燥速率,结果的准确性高、重现性好。 展开更多
关键词 干燥速率 蒸发速率 ORIGIN软件 曲线拟合 切线斜率
原文传递
Call for Papers from Food Science of Animal Products
2
《肉类研究》 北大核心 2026年第1期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects. 展开更多
关键词 animal origin foods EGGS animal offals food materials MEAT MILK food science animal products issn e issn edible insects
在线阅读 下载PDF
Guidelines for Authors
3
《Chinese Journal of Polymer Science》 2026年第1期I0001-I0003,共3页
Submission.Papers appearing in the Journal comprise Editorials,Rapid Communications,Perspectives,Tutorials,Feature Articles,Reviews,Research Articles,which should contain original information,theoretical or experiment... Submission.Papers appearing in the Journal comprise Editorials,Rapid Communications,Perspectives,Tutorials,Feature Articles,Reviews,Research Articles,which should contain original information,theoretical or experimental,on any topics in the field of polymer science and polymer material science.Papers already published or scheduled to be published elsewhere should not be submitted and certainly will not be accepted. 展开更多
关键词 polymer science original information rapid communications polymer material science PERSPECTIVES EDITORIALS THEORETICAL experimental
原文传递
Hepatobiliary&Pancreatic Diseases International
4
《Hepatobiliary & Pancreatic Diseases International》 2026年第1期I0006-I0008,共3页
General information Hepatobiliary&Pancreatic Diseases International is a journal published bimonthly in the English language by the First Affiliated Hospital,Zhejiang University School of Medicine,Hangzhou,China.W... General information Hepatobiliary&Pancreatic Diseases International is a journal published bimonthly in the English language by the First Affiliated Hospital,Zhejiang University School of Medicine,Hangzhou,China.We welcome original research articles,review articles,editorials,and others from any part of the world.Manuscripts are reviewed by members of the international editorial board and our expert peer reviewers,then either accepted for publication or rejected by the chief editor.Manuscripts should. 展开更多
关键词 hepatobiliary diseases review articles original research articles EDITORIALS pancreatic diseases international journal
暂未订购
Instructions for Authors
5
《International Journal of Minerals,Metallurgy and Materials》 2026年第2期I0001-I0001,共1页
International Journal of Minerals,Metallurgy and Materials is dedicated to the publication and the dissemination of original research articles(and occasional invited reviews)in the fields of Minerals,Metallurgy and Ma... International Journal of Minerals,Metallurgy and Materials is dedicated to the publication and the dissemination of original research articles(and occasional invited reviews)in the fields of Minerals,Metallurgy and Materials.It is covered by EI Compendex,SCI Expanded,Chemical Abstract,etc. 展开更多
关键词 METALLURGY MINERALS invited reviews original research articles ei compendex sci expanded chemical abstract materials
暂未订购
Information for authors
6
《Chinese Chemical Letters》 2026年第1期I0004-I0005,共2页
Chinese Chemical Letters(CCL)(ISSN 1001-8417)was founded in July 1990.The journal publishes preliminary accounts in the whole field of chemistry,including inorganic chemistry,organic chemistry,analytical chemistry,phy... Chinese Chemical Letters(CCL)(ISSN 1001-8417)was founded in July 1990.The journal publishes preliminary accounts in the whole field of chemistry,including inorganic chemistry,organic chemistry,analytical chemistry,physical chemistry,polymer chemistry,applied chemistry,etc.,satisfying a real and urgent need for the dissemination of research results,especially hot topics.The journal does not accept articles previously published or scheduled to be published.To verify originality,your article may be checked by the originality detection service Cross Check. 展开更多
关键词 CHEMISTRY preliminary accounts applied chemistry organic chemistry polymer chemistry analytical chemistry originality detection inorganic chemistry
原文传递
GUIDE FOR AUTHORS
7
《Plant Diversity》 2026年第1期I0003-I0007,共5页
Introduction Types of paper Contributions falling into the following categories will be considered for publication:original articles,review articles,short letters,modelling/theory and methods articles,rapid reports an... Introduction Types of paper Contributions falling into the following categories will be considered for publication:original articles,review articles,short letters,modelling/theory and methods articles,rapid reports and special thematic issues.Please ensure that you select the appropriate article type from the list of options when making your submission.Authors contributing to special issues should ensure that they select the special issue article type from this list. 展开更多
关键词 review articles modelling theory methods articles original articles short letters rapid reports special thematic issues
在线阅读 下载PDF
Defence Technology Aims and Scope
8
《Defence Technology(防务技术)》 2026年第2期F0002-F0002,共1页
Defence Technology(ISSN 2214-9147(O);2096-3459(P)),sponsored by China Ordnance Society,is published monthly and aims to become one of the well-known comprehensive journals in the world,which reports on the breakthroug... Defence Technology(ISSN 2214-9147(O);2096-3459(P)),sponsored by China Ordnance Society,is published monthly and aims to become one of the well-known comprehensive journals in the world,which reports on the breakthroughs in defence technology by building up an international academic exchange platform for the defence technology related research.It publishes original research papers having direct bearing on defence,with a balanced coverage on analytical,experimental,numerical simulation and applied investigations.It covers various disciplines of science,technology and engineering. 展开更多
关键词 defence technology applied investigation original research papers analytical methods academic exchange platform breakthroughs experimental methods international academic exchange
在线阅读 下载PDF
Summary of Guide for Authors
9
《International Journal of Nursing Sciences》 2026年第1期10-10,共1页
International Journal of Nursing Sciences(IJNSS,Print ISSN 2096-6296,and Online ISSN 2352-0132,CN10-1444/R)is the official peer-reviewed research journal of the Chinese Nursing Association.The IJNSS publishes original... International Journal of Nursing Sciences(IJNSS,Print ISSN 2096-6296,and Online ISSN 2352-0132,CN10-1444/R)is the official peer-reviewed research journal of the Chinese Nursing Association.The IJNSS publishes original research papers,reviews,discussion papers,editorial and letters to the editor. 展开更多
关键词 EDITORIAL REVIEWS Chinese Nursing Association international journal nursing sciences ijnssprint International Journal Discussion Papers Peer reviewed Research Journal Original Research Papers
暂未订购
Adhering to our original aspiration,forging ahead with determination-Editor in Chief's new year address
10
作者 Chuan Qin 《Animal Models and Experimental Medicine》 2026年第1期3-4,I0002,共3页
On the occasion of the New Year,I would like to extend my sincere gratitude and New Year greetings to the experts,scholars,author teams,and readers who have long supported the development of Animal Models and Experime... On the occasion of the New Year,I would like to extend my sincere gratitude and New Year greetings to the experts,scholars,author teams,and readers who have long supported the development of Animal Models and Experimental Medicine(AMEM).Over the past year,we have faced challenges together and achieved breakthroughs in academic influence,internationalization,and fulfilling social respon-sibilities.Looking ahead,we are filled with confidence as we strive to build an important bridge connecting laboratory animal science and technology with academic research. 展开更多
关键词 build important bridge connecting laboratory animal editor chief experts GRATITUDE forging ahead animal models experimental medicine amem original aspiration new year address
暂未订购
Detection of white matter microstructural changes in patients with systemic lupus erythematosus based on multiple diffusion models and related diffusion metrics
11
作者 Zhenxing Li Huanhuan Li +5 位作者 Bailing Tian Huiyang Liu Yueluan Jiang Pingting Yang Guoguang Fan Hu Liu 《Neural Regeneration Research》 2026年第6期2467-2474,共8页
Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle... Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle to accurately capture microstructural changes.Various diffusion models have been used to study white matter in systemic lupus erythematosus;however,comparative analyses of their sensitivity and specificity for detecting microstructural changes remain insufficient.To address this,our team designed a diagnostic trial that used multimodal diffusion imaging techniques to observe white matter microstructural changes in patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with an aim to identify key diagnostic biomarkers for these patients.Patients with active lupus who received treatment at the Department of Rheumatology and Immunology,The First Affiliated Hospital of China Medical University,from September 2023 to March 2024 were recruited.According to the standards of the American College of Rheumatology,patients with systemic lupus erythematosus who had neuropsychiatric symptoms were assigned to the systemic lupus erythematosus group,whereas those without neuropsychiatric symptoms were assigned to the non-systemic lupus erythematosus group.Additionally,healthy volunteers matched by region,sex,and age were recruited as controls.All three groups underwent the same diffusion magnetic resonance imaging examination protocol to compare differences in diffusion parameters.Advanced diffusion imaging models were able to sensitively detect microstructural changes in the white matter fibers of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with specific diffusion parameters showing significant abnormalities in key brain regions.In the left superior longitudinal fasciculus subregion and the right thalamic radiations of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,we also identified abnormal diffusion characteristics that were clearly correlated with disease activity,suggesting that microstructural changes in these areas may reflect the dynamic process of neuroinflammatory damage.The present study addresses critical challenges in the diagnosis of systemic lupus erythematosus by identifying specific white matter imaging biomarkers and elucidating the association between microstructural damage and clinical manifestations.The main contributions of our study include:1)establishing axial regression probability parameters from mean apparent propagator magnetic resonance imaging as sensitive biomarkers for systemic lupus erythematosus,particularly in the third subregion of the left superior longitudinal fasciculus;2)demonstrating that multimodal diffusion imaging may be superior to conventional diffusion tensor imaging for detecting white matter microstructural abnormalities in patients with systemic lupus erythematosus;and 3)integrating tract-based spatial statistics with clinically relevant analyses to link imaging findings to pathological mechanisms. 展开更多
关键词 diffusion kurtosis imaging diffusion tensor imaging mean apparent propagator neurite orientation dispersion and density imaging neuropsychiatric systemic lupus erythematosus return to axis probability return to origin probability superior longitudinal fasciculus-3 superior thalamic radiation tract-based spatial statistics white matter microstructure
暂未订购
基于热线法探究冰的导热系数与温度的关系 被引量:1
12
作者 陈嘉希 夏湘芳 +3 位作者 钟振文 宋景良 陈光伟 刘宗华 《大学物理实验》 2025年第4期84-88,共5页
基于热线法测量材料导热系数原理结合半导体制冷片设计制作了冰的导热系数实验装置,与循环水冷系统配套置于冰柜中,对冰的导热系数进行测量。其测量过程为采用铂丝作为热线和开尔文四线制接线法,利用测量电压和电流计算出对应温度下铂... 基于热线法测量材料导热系数原理结合半导体制冷片设计制作了冰的导热系数实验装置,与循环水冷系统配套置于冰柜中,对冰的导热系数进行测量。其测量过程为采用铂丝作为热线和开尔文四线制接线法,利用测量电压和电流计算出对应温度下铂丝的电阻值,再换算出Pt100相同温度下的阻值,并记录下对应的时间,求出温度随时间对数的变化率。从而测得-28.7~-1.23℃的冰的导热系数在1.5至2.7 W/(m·K)之间,且冰的导热系数随温度的降低而升高,并可通过Origin软件准确拟合出其关系。 展开更多
关键词 热线法 冰的导热系数 半导体制冷 Origin拟合
在线阅读 下载PDF
使用DRS origin软件建立HPLC替代对照品法测定防风中升麻素苷、5-O-甲基维斯阿米醇苷、升麻素、亥茅酚苷的含量
13
作者 孔德娟 左甜甜 +5 位作者 盛雪 嵇增云 邹广鑫 田佳勋 王艳楠 闫凤杰 《中国新药杂志》 北大核心 2025年第21期2316-2325,共10页
目的:建立双标多测法(TRSDMC)同时测定防风中升麻素苷、5-O-甲基维斯阿米醇苷、升麻素、亥茅酚苷的含量,节约对照品同时更全面地控制该品种的质量。方法:采用HPLC法测定,使用C 18色谱柱;流动相为乙腈(A)-0.1%甲酸水(B),流速1.0 mL·... 目的:建立双标多测法(TRSDMC)同时测定防风中升麻素苷、5-O-甲基维斯阿米醇苷、升麻素、亥茅酚苷的含量,节约对照品同时更全面地控制该品种的质量。方法:采用HPLC法测定,使用C 18色谱柱;流动相为乙腈(A)-0.1%甲酸水(B),流速1.0 mL·min^(-1),梯度洗脱;柱温35℃;检测波长254 nm;进样体积10μL。以升麻素苷和5-O-甲基维斯阿米醇苷为对照,使用DRS origin软件进行双标线性校正预测特征峰的保留时间,并通过替代对照品法获得相对校正因子,计算结果与外标法进行比较。结果:通过DRS origin软件拟合的标准曲线预测待测化合物准确,并结合校正因子计算所得含量与外标法测定结果比较,绝对偏差均<0.2 mg·g^(-1),准确度均大于95.0%。24批次样品中升麻素苷、升麻素、5-O-甲基维斯阿米醇苷、亥茅酚苷含量范围分别为0.8399~3.7996、0.0206~0.1718、0.6773~2.5099、0.0457~0.2032 mg·g^(-1)。结论:双标线性校正预测保留时间与相对保留时间法相比,前者保留时间预测结果准确度高,色谱柱的适用范围广,为防风多指标含量测定提供了新的思路和方法。 展开更多
关键词 防风 升麻素苷 升麻素 5-O-甲基维斯阿米醇苷 亥茅酚苷 替代对照品法 DRS origin软件
原文传递
基于phyphox和Origin软件的牛顿第二定律实验研究
14
作者 邹兆轩 伏森泉 +4 位作者 丁益民 程文睿 刘沁 苏鹏 陈九江 《物理通报》 2025年第5期90-93,97,共5页
借助phyphox和Origin软件,利用手机或平板这种自带深度传感器的现代技术设备,对牛顿第二定律的实验进行优化与创新,并将实验数值与理论数值进行对比,实验结果准确地验证了牛顿第二定律的准确性.这样的实验方法在提高实验教学的可视化程... 借助phyphox和Origin软件,利用手机或平板这种自带深度传感器的现代技术设备,对牛顿第二定律的实验进行优化与创新,并将实验数值与理论数值进行对比,实验结果准确地验证了牛顿第二定律的准确性.这样的实验方法在提高实验教学的可视化程度和可操作性的同时,还有利于培养学生处理和分析图像的能力,发展学生核心素养. 展开更多
关键词 phyphox ORIGIN 牛顿第二定律 中学物理
在线阅读 下载PDF
49-2反应堆活性区支架放射性源项计算分析
15
作者 麻雪逸 张亚东 陈晓亮 《科学技术创新》 2025年第19期54-57,共4页
核设施退役逐渐发展成为世界范围的问题,作为整个退役项目开始的先决条件——源项调查尤为重要。本文针对49-2反应堆的活性区支架进行放射性源项计算与分析。首先利用MCNP程序建立堆芯的计算模型,并完成堆芯结构部件处中子通量分布的计... 核设施退役逐渐发展成为世界范围的问题,作为整个退役项目开始的先决条件——源项调查尤为重要。本文针对49-2反应堆的活性区支架进行放射性源项计算与分析。首先利用MCNP程序建立堆芯的计算模型,并完成堆芯结构部件处中子通量分布的计算。随后以中子通量、反应堆功率运行史等数据为输入,利用ORIGEN程序计算各中子活化产物的源项信息。最后通过与实际测量数据进行对比,验证本文所采用计算方法的合理性以及源项数据的准确性。 展开更多
关键词 源项计算 MCNP程序 ORIGIN程序
在线阅读 下载PDF
Origin and distribution model of thin dolomite reservoirs in the lower sub-member of Mao 2 Member of Middle Permian Maokou Formation in Wusheng-Tongnan area,Sichuan Basin,SW China 被引量:2
16
作者 TAN Xiucheng HE Ruyi +7 位作者 YANG Wenjie LUO Bing SHI Jiangbo ZHANG Lianjin LI Minglong TANG Yuxin XIAO Di QIAO Zhanfeng 《Petroleum Exploration and Development》 2025年第1期125-142,共18页
This paper discusses the characteristics and formation mechanism of thin dolomite reservoirs in the lower submember of the second member of the Permian Maokou Formation(lower Mao 2 Member)in the Wusheng-Tongnan area o... This paper discusses the characteristics and formation mechanism of thin dolomite reservoirs in the lower submember of the second member of the Permian Maokou Formation(lower Mao 2 Member)in the Wusheng-Tongnan area of the Sichuan Basin,SW China,through comprehensive analysis of geological,geophysical and geochemical data.The reservoir rocks of the lower Mao 2 Member are dominated by porphyritic vuggy dolomite and calcareous dolomite or dolomitic limestone,which have typical karst characteristics of early diagenetic stage.The dolomites at the edge of the karst system and in the fillings have dissolved estuaries,and the dolomite breccia has micrite envelope and rim cement at the edge,indicating that dolomitization is earlier than the early diagenetic karstification.The shoal facies laminated dolomite is primarily formed by the seepage reflux dolomitization of moderate-salinity seawater.The key factors of reservoir formation are the bioclastic shoal deposition superimposed with seepgae reflux dolomitization and the karstification of early diagenetic stage,which are locally reformed by fractures and hydrothermal processes.The development of dolomite vuggy reservoir is closely related to the upward-shallowing sequence,and mainly occurs in the late highstand of the fourth-order cycle.Moreover,the size of dolomite is closely related to formation thickness,and it is concentrated in the formation thickness conversion area,followed by the thinner area.According to the understanding of insufficient accommodation space in the geomorphic highland and the migration of granular shoal to geomorphic lowland in the late highstand of the third-order cycle,it is proposed that the large-scale shoal-controlled dolomite reservoirs are distributed along structural highs and slopes,and the reservoir-forming model with shoal,dolomitization and karstification jointly controlled by the microgeomorphy and sea-level fluctuation in the sedimentary period is established.On this basis,the paleogeomorphology in the lower Mao 2 Member is restored using well-seismic data,and the reservoir distribution is predicted.The prediction results have been verified by the latest results of exploration wells and tests,which provide an important reference for the prediction of thin dolomite reservoirs under similar geological setting. 展开更多
关键词 reservoir origin sedimentary paleogeomorphology granular shoal thin reservoir DOLOMITE vuggy reservoir KARST Middle Permian Maokou Formation Sichuan Basin
在线阅读 下载PDF
An Analysis about the Origin and Essence of Mass Based on Particle-Propagating Model and Wave Equations of Scalar Waves 被引量:1
17
作者 Jiang Jian-zhong Chen Xi-qi 《Journal of Environmental Science and Engineering(B)》 2025年第2期65-75,共11页
If the singularity of the cosmic Big Bang is taken as the origin of the reference coordinate system,the surrounding vacuum in the initial moments of it would exhibit radially-outward right-handed spiral motion at ligh... If the singularity of the cosmic Big Bang is taken as the origin of the reference coordinate system,the surrounding vacuum in the initial moments of it would exhibit radially-outward right-handed spiral motion at light speed.Based on this spatial motion hypothesis,we derive a unified field equation and a set of Maxwell’s equations for vacuum SWs(Scalar Waves)generating a huge spiral force field that drives the energy to spiral inwardly and distort,leading to the formation of mass.Furthermore,they also uncover that mass is fundamentally an ultimate expression of energy,manifesting as the result of spiral motion of space at light speed.And then,we indirectly validate the theory that coherent light waves’collision generate SWs and subsequently mass through the experiment verifying the Breit-Wheeler process.The establishment of our theory offers a new analytical tool for the exploration of mass origin,the cosmic Big Bang,unified field theories. 展开更多
关键词 QED(Quantum Electrodynamics) SW mass origin unified field theories
在线阅读 下载PDF
Ancient genomic analysis of a Chinese hereditary elite from the Northern and Southern Dynasties 被引量:1
18
作者 Yao Yu Xiaomin Yang +12 位作者 Daiyun Liu Panxin Du e Hailiang Meng Zixiao Huang Jianxue Xiong Yi Ding Xiaoying Ren Edward Allen Hui Wang Sheng Han Li Jin Chuan-Chao Wang Shaoqing Wen 《Journal of Genetics and Genomics》 2025年第4期473-482,共10页
China's Northern and Southern Dynasties period(3rd–6th centuries AD)marked a significant era of ethnic integration in northern China.However,previous ancient DNA studies have primarily focused on northern ethnic ... China's Northern and Southern Dynasties period(3rd–6th centuries AD)marked a significant era of ethnic integration in northern China.However,previous ancient DNA studies have primarily focused on northern ethnic groups,with limited research on the genetic formation of the hereditary elite family,especially considering their abundant archaeological record and clear material identity.In this study,we obtain the ancient genome of a hereditary elite family,Gao Bin(高宾,503 AD–572 AD),at 0.6473-fold coverage with 475,132 single-nucleotide polymorphisms(SNPs)on the 1240k panel.His mitochondrial haplogroup belongs to Z4 and Y-haplogroup to O1a1a2b-F2444∗.The genetic profile of Gao Bin is most similar to that of the northern Han Chinese.He can be modeled as deriving all his ancestry from Late Neolithic to Iron Age Yellow River farmers without influence from Northeast Asia,Korea,or the Mongolian Plateau.Our study sheds light on the genetic formation of hereditary elite families in the context of the Southern and Northern Dynasties ethnic integration. 展开更多
关键词 Ancient DNA Hereditary elite Population admixture Bohai Gao Branch Korean Goguryeo origin
原文传递
Deciphering origins of hydrocarbon deposits by means of intramolecular carbon isotopes of propane adsorbed on sediments 被引量:1
19
作者 Peng Liu Xiao-Feng Wang +6 位作者 Jie Wang Juske Horita Zhi-Yong Wang Ying Lin Rui-Liang Guo Fu-Qi Li Wen-Hui Liu 《Petroleum Science》 2025年第2期546-556,共11页
Hydrocarbons are one of the important fluids within the Earth's crust,and different biotic and abitoic processes can generate hydrocarbon during geological periods.Tracing the sources and sinks of hydrocarbons can... Hydrocarbons are one of the important fluids within the Earth's crust,and different biotic and abitoic processes can generate hydrocarbon during geological periods.Tracing the sources and sinks of hydrocarbons can help us better understand the carbon cycle of the earth.In this study,an improved approach of adsorbed hydrocarbons extraction from sediments was established.The improved thermal desorption approach,compound-specific isotope analysis and position-specific isotope analysis were integrated to investigate the molecular and intramolecular isotope fractionation between trace hydrocarbon gases within sediments and geological hydrocarbon deposits.The isotopic compositions of the terminal position carbon of propane(δ^(13)C_(terminal))serves as a correlation indicator between trace hydrocarbon gases within sediments and geological hydrocarbon deposits.The tight sandstone gas from the Turpan-Hami Basin is a first case study for the application of this novel method to trace hydrocarbon origins.The results showed that the hydrocarbons in the tight sandstone gases in the study area most likely originated from humic organic matter(typeⅢkerogen)at an early mature stage.δ^(13)C_(terminal)values of the thermally desorbed propane gases from different source rocks were distinguishable and the values of the tight sandstone gases significantly overlap with those of the Lower Jurassic Sangonghe source rocks,suggesting their genetic relationship.Overall,the results provided novel position-specific carbon isotopic constraints on origins of hydrocarbons. 展开更多
关键词 Hydrocarbon origins Intramolecular isotope distributions Position-specific isotope analysis(PSIA) PROPANE
原文传递
巧用Origin软件构建种群密度数学模型——以“黑光灯诱捕法调查封闭环境中某种昆虫种群密度实验”为例
20
作者 薛丽华 《中学生物教学》 2025年第9期62-64,共3页
在高中生物学教学中,数学模型的构建可以利用Origin软件来处理数据,得到直观的拟合图像。在“黑光灯诱捕法调查封闭环境中某种昆虫种群密度实验”中,利用Origin软件进行数据的线性拟合,得到了单次捕获数目(y)和累积捕获数目(x)的线性拟... 在高中生物学教学中,数学模型的构建可以利用Origin软件来处理数据,得到直观的拟合图像。在“黑光灯诱捕法调查封闭环境中某种昆虫种群密度实验”中,利用Origin软件进行数据的线性拟合,得到了单次捕获数目(y)和累积捕获数目(x)的线性拟合数学模型,简单明了地推测出种群数量估算值,计算出种群密度。 展开更多
关键词 数学模型 ORIGIN软件 线性拟合
在线阅读 下载PDF
上一页 1 2 137 下一页 到第
使用帮助 返回顶部