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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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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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Unroofing Technique for Anomalous Origin of the Left Coronary Artery from the Right Sinus of Valsalva: Report of a Case
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作者 Keisuke Morimoto Futoshi Kobayashi +2 位作者 Hiromu Horie Yuki Sakaguchi Einosuke Mizuta 《World Journal of Cardiovascular Surgery》 2024年第6期69-77,共9页
Anomalous origin of the left coronary artery (AOLCA) from the right sinus of Valsalva constitutes a rare congenital coronary artery anomaly. Patients with an anomalous left main coronary artery face a significantly hi... Anomalous origin of the left coronary artery (AOLCA) from the right sinus of Valsalva constitutes a rare congenital coronary artery anomaly. Patients with an anomalous left main coronary artery face a significantly higher risk of sudden cardiac death compared to those with an anomalous right coronary artery. The anomalous coronary artery traversing between the ascending aorta and the pulmonary artery markedly heightens the risk of myocardial ischemia, arrhythmia, and sudden death. Symptomatic patients often exhibit a longer intramural course of the coronary artery, which may necessitate earlier intervention or influence the choice of surgical repair method. Surgical intervention is advocated for patients with this anomaly, even in the absence of symptoms. For anomalous aortic origin of a coronary artery from the opposite sinus of Valsalva with an intramural course, coronary unroofing is the preferred revascularization procedure. This report presents a case of AOLCA originating from the right sinus of Valsalva, treated surgically using the unroofing technique for the aortic intramural segment of the anomalous coronary artery traversing between the great vessels. The unroofing technique is recommended for treating AOLCA with an extensive intramural course that does not involve the commissure. 展开更多
关键词 Unroofing Technique Anomaly of Coronary Artery Anomalous origin of Left Coronary Artery
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新疆地区人群非综合征型唇腭裂与外周血FOXN3-SIN3A复合物表达量相关性研究
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作者 多力昆·吾甫尔 地丽拜尔·依明江 +2 位作者 卡米力江·买买提明 李军 乌丽凡·托勒恒 《华西口腔医学杂志》 CAS CSCD 北大核心 2024年第3期313-318,共6页
目的研究FOXN3-SIN3A复合物表达量与新疆地区人群非综合征型唇腭裂(NSOC)的相关性。方法本研究选取就诊于新疆维吾尔自治区人民医院的NSOC患者60例为病例组,其中唇裂伴或不伴腭裂(NSCL/P)30例,单纯腭裂(CPO)30例,对照组为30例健康儿童... 目的研究FOXN3-SIN3A复合物表达量与新疆地区人群非综合征型唇腭裂(NSOC)的相关性。方法本研究选取就诊于新疆维吾尔自治区人民医院的NSOC患者60例为病例组,其中唇裂伴或不伴腭裂(NSCL/P)30例,单纯腭裂(CPO)30例,对照组为30例健康儿童。采用高通量二代测序技术及定量逆转录聚合酶链反应(RT-qPCR)检测各组外周血中FOXN3、SIN3A和NEAT1的表达量,分析受试者工作特征(ROC)曲线和曲线下面积(AUC),采用卡方检验对NSOC和对照组FOXN3、SIN3A和NEAT1的表达量进行比较。结果NSCL/P组和CPO组患者FOXN3、SIN3A、NEAT1基因表达较对照组均上升,差异均有统计学意义(P<0.05)。NSCL/P组FOXN3、SIN3A、NEAT1的基因序列AUC分别为0.933[95%CI=(0.864,1.000)]、0.822[95%CI=(0.713,0.932)]、1.000[95%CI=(1.000,1.000)];CPO组FOXN3、SIN3A、NEAT1的基因序列AUC分别为0.891[95%CI=(0.806,0.976)]、0.688[95%CI=(0.552,0.824)]、1.000[95%CI=(1.000,1.000)]。结论外周血FOXN3、SIN3A、NEAT1基因表达上升与新疆地区NSOC的发生存在相关性,可以对将来进一步研究FOXN3-SIN3A复合物作为生物标记物,从而对NSOC的早期筛查、患病预测和早期预防提供理论依据。 展开更多
关键词 非综合征型唇腭裂 FOXN3 sin3A NEAT1 生物标记物
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GNSS/SINS/视觉导航鲁棒算法 被引量:1
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作者 李明 柴洪洲 郑乃铨 《南京信息工程大学学报(自然科学版)》 CAS 北大核心 2024年第1期114-119,共6页
全球导航卫星系统(Global Navigation Satellite System, GNSS)、捷联惯性导航系统(Strapdown Inertial Navigation System, SINS)和视觉传感器优势互补,3者信息融合可获得高精度、无漂移的导航定位信息.针对GNSS/SINS/视觉融合导航易... 全球导航卫星系统(Global Navigation Satellite System, GNSS)、捷联惯性导航系统(Strapdown Inertial Navigation System, SINS)和视觉传感器优势互补,3者信息融合可获得高精度、无漂移的导航定位信息.针对GNSS/SINS/视觉融合导航易受运动速度、光照变化、遮挡等影响导致定位精度和鲁棒性降低问题,本文在图优化框架的代价函数中加入SoftLOne鲁棒核函数,设置量测值粗差检验程序,降低离群点带来的负面影响.进一步,对量测值计算残差进行卡方检验,对超限残差降权处理,提高系统精度和鲁棒性.实验结果表明,本文算法较不施加鲁棒核函数、不采用异常值剔除策略和卡方检验的传统算法,以及加入其他鲁棒核函数的算法精度更高、鲁棒性更好,能够较大程度提升GNSS/SINS/视觉导航定位精度和鲁棒性,在大尺度环境下,未出现较大漂移误差,绝对位姿均方根误差0.735 m,绝对位姿误差标准差0.336 m. 展开更多
关键词 全球导航卫星系统 捷联惯性导航系统 视觉 鲁棒算法 卡方检验
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Overpressure origins and evolution in deep-buried strata:A case study of the Jurassic Formation,central Junggar Basin,western China 被引量:1
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作者 Qiao-Chu Wang Dong-Xia Chen +7 位作者 Xian-Zhi Gao Mei-Jun Li Xue-Bin Shi Fu-Wei Wang Si-Yuan Chang Dong-Sheng Yao Sha Li Shu-Min Chen 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1429-1445,共17页
Overpressure is significant to the exploration and exploitation of petroleum due to its influence on hydrocarbon accumulation and drilling strategies.The deep-burial hydrocarbon reservoirs of Jurassic strata in the ce... Overpressure is significant to the exploration and exploitation of petroleum due to its influence on hydrocarbon accumulation and drilling strategies.The deep-burial hydrocarbon reservoirs of Jurassic strata in the central Junggar Basin are characterized by intensive overpressure,whose origins are complex and still unclear.In this study,Bowers'method and sonic velocity-density crossplot method based on well logging data were used as a combination for overpressure judgements in geophysics.Furthermore,the corresponding geological processes were analysed in quality and quantity to provide a rational comprehension of the overpressure origins and the model of overpressure evolution and hy-drocarbon accumulation processes.The results showed that hydrocarbon generation in the Jurassic source rocks led to overpressure in the mudstones,while hydrocarbon generation in Permian source rocks led to overpressure in the sandstone reservoirs in Jurassic strata by vertical pressure transfer.The burial and thermal history indicated that the aquathermal effect of pore fluids by temperature increase in deep strata is also an important origin of overpressure,while disequilibrium compaction may not be the dominant cause for the overpressure in deep-buried strata.Furthermore,the continuous tectonic compression in both the north-south and west-east trends from the Jurassic period to the present may also have enhanced the overpressure in deep strata.Meanwhile,the developed faults formed by intensive tectonic compression led to pressure transfer from source rocks to the Jurassic reservoirs.Overpressured geofluids with hydrocarbons migrated to sandstone reservoirs and aggravated the over-pressure in the Jurassic strata.To conclude,the intensive overpressure in the central Junggar Basin is attributed to the combination of multiple mechanisms,including hydrocarbon generation,the aqua-thermal effect,tectonic compression and pressure transfer.Furthermore,the developed overpressure indicated hydrocarbon migration and accumulation processes and the potential of oil and gas reservoirs in deeply buried strata.We hope this study will provide a systematic research concept for overpressure origin analysis and provide guidance for petroleum exploration and exploitation in deep-buried strata. 展开更多
关键词 origin of overpressure Hydrocarbon generation Tectonic compression Overpressure transfer Junggar Basin
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北斗/SINS/OD组合导航定位终端设计
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作者 邢昱翔 赵英亮 +4 位作者 姚金杰 姚焕钰 邹宇 薛晓东 刘蔚 《集成电路与嵌入式系统》 2024年第1期83-88,共6页
针对常见组合导航系统在隧道、峡谷、森林等卫星信号较弱甚至出现失锁状况的地区,定位精度会迅速下降的问题,设计了北斗/捷联惯导(SINS)/里程计(OD)组合导航定位终端。终端设计以OMAPL137处理器为核心,包括北斗、SINS、里程计、4G通信... 针对常见组合导航系统在隧道、峡谷、森林等卫星信号较弱甚至出现失锁状况的地区,定位精度会迅速下降的问题,设计了北斗/捷联惯导(SINS)/里程计(OD)组合导航定位终端。终端设计以OMAPL137处理器为核心,包括北斗、SINS、里程计、4G通信和电源等模块。数据处理部分以北斗导航接收机和根据SINS/OD推算分别得到的伪距、伪距率之间的差值作为量测值,使用拓展卡尔曼(EKF)滤波算法进行数据融合与误差估计。实验结果表明,北斗/SINS/OD组合导航定位终端在卫星失锁情况下行驶总里程5 km时最大位置误差为46.82 m,误差漂移为0.94%,能够有效解决卫星信号受遮蔽导致定位精度下降的问题,实现平滑载体运行轨迹并提高导航定位精度。 展开更多
关键词 北斗 sinS OD OMAPL137
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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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车载GNSS/SINS/里程计分布式弹性融合导航方法
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作者 穆梦雪 赵龙 《测绘学报》 EI CSCD 北大核心 2024年第3期425-434,共10页
为提升复杂环境下低成本车载导航系统的容错性能,本文研究了基于次优增益融合(SGF)算法的GNSS/SINS/里程计分布式弹性融合方法。该方法首先根据阿克曼转向几何建立了四轮里程计测速补偿模型,提升了惯性测量单元(IMU)安装中心处的前向和... 为提升复杂环境下低成本车载导航系统的容错性能,本文研究了基于次优增益融合(SGF)算法的GNSS/SINS/里程计分布式弹性融合方法。该方法首先根据阿克曼转向几何建立了四轮里程计测速补偿模型,提升了惯性测量单元(IMU)安装中心处的前向和侧向测速精度;然后设计了基于卡方检验统计量的故障检测与分类准则,充分利用了可获取的观测信息;最后构建了随机模型和信息分配因子(ISF)弹性优化模型,分别从传感器层和决策层减少了异常观测的影响,实现了车载多源信息的弹性融合。通过实际跑车数据对GNSS/SINS/里程计分布式弹性融合方法进行测试验证。试验结果表明,本文方法能有效减少子系统故障对全局状态估计的影响,提升复杂环境下系统的容错性能。此外,与经典的联邦卡尔曼滤波(FKF)算法相比,SGF算法全局融合精度损失有限,计算效率却显著提升,有利于多源信息弹性融合的实际工程应用。 展开更多
关键词 多源信息弹性融合 GNSS/sinS/里程计融合 里程计测速补偿模型 次优增益融合 分布式滤波
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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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The Original Organism Assemblages and Kerogen Carbon Isotopic Compositions of the Early Paleozoic Source Rocks in the Tarim Basin, China 被引量:2
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作者 HU Guang MENG Qingqiang +5 位作者 WANG Jie Tengger XIE Xiaomin LU Longfei LUO Houyong LIU Wenhui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第6期2297-2309,共13页
Original organisms are the biological precursors of organic matter in source rocks. Original organisms in source rocks are informative for oil-source rock correlation and hydrocarbon potential evaluation, especially f... Original organisms are the biological precursors of organic matter in source rocks. Original organisms in source rocks are informative for oil-source rock correlation and hydrocarbon potential evaluation, especially for source rocks which have high-over level of thermal maturity. Systematic identification of original organism assemblages of the Lower Paleozoic potential source rocks and detailed carbon isotopic composition of kerogen analyses were conducted for four outcrop sections in the Tarim basin. Results indicated that the original organism assemblages of the lower part of the Lower Cambrian were composed mainly of benthic algae, whereas those of the Upper Cambrian and the Ordovician were characterized by planktonic algae. Kerogen carbon isotopic data demonstrated that the δ13 Ckerogen values of source rocks dominated by benthic algae are lower than-34‰, whereas the δ13 Ckerogen values of source rocks dominated by planktonic algae are higher than-30‰ in general. We tentatively suggested that the carbon species those are utilized by algae and the carbon isotopic fractionation during photosynthesis are the major controls for the δ13 Ckerogen values in the Lower Paleozoic source rocks in the Tarim basin. Correlating the δ13 C values of oils exploited in the Tarim basin, the original organism assemblages, and δ13 Ckerogen values of source rocks, it implied that the Lower Paleozoic oils exploited in the Tarim basin should be sourced from the source rocks with original organism assemblages dominated by planktonic algae, and the hydrocarbon sourced from the Cambrian benthic algae should be of great exploration potential in future. Original organism assemblages in source rocks can provide important clues for oil-source rocks correlation, especially for the source rocks with high thermal maturity. 展开更多
关键词 Tarim basin the Lower Paleozoic source rock original organisms kerogen carbon isotopes
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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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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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Petroleum geochemistry and origin of shallow-buried saline lacustrine oils in the slope zone of the Mahu sag, Junggar Basin, NW China
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作者 Dong-Yong Wang Mei-Jun Li +6 位作者 Yang Zhou Lu Yang Yuan-Feng Yang Er-Ting Li Jun Jin Xian-Li Zou Bo-Dong Xu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3363-3378,共16页
Recently, significant oil discoveries have been made in the shallower pay zones of the Jurassic Badaowan Formation (J_(1)b) in the Mahu Sag, Junggar Basin, Northwest China. However, little work has been done on the ge... Recently, significant oil discoveries have been made in the shallower pay zones of the Jurassic Badaowan Formation (J_(1)b) in the Mahu Sag, Junggar Basin, Northwest China. However, little work has been done on the geochemical characteristics and origins of the oil in the J_(1)b reservoir. This study analyzes 44 oil and 14 source rock samples from the area in order to reveal their organic geochemical characteristics and the origins of the oils. The J_(1)b oils are characterized by a low Pr/Ph ratio and high β-carotene and gammacerane indices, which indicate that they were mainly generated from source rocks deposited in a hypersaline environment. The oils are also extremely enhanced in C_(29) regular steranes, possibly derived from halophilic algae. Oil-source correlation shows that the oils were derived from the Lower Permian Fengcheng Formation (P_(1)f) source rocks, which were deposited in a strongly stratified and highly saline water column with a predominance of algal/bacterial input in the organic matter. The source rocks of the Middle Permian lower-Wuerhe Formation (P_(2)w), which were deposited in fresh to slightly saline water conditions with a greater input of terrigenous organic matter, make only a minor contribution to the J_(1)b oils. The reconstruction of the oil accumulation process shows that the J_(1)b oil reservoir may have been twice charged during Late Jurassic–Early Cretaceous and the Paleogene–Neogene, respectively. A large amount volume of hydrocarbons generated in the P_(1)f source rock and leaked from T_(1)b oil reservoirs migrated along faults connecting source beds and shallow-buried secondary faults into Jurassic traps, resulting in large-scale accumulations in J_(1)b. These results are crucial for understanding the petroleum system of the Mahu Sag and will provide valuable guidance for petroleum exploration in the shallower formations in the slope area of the sag. 展开更多
关键词 Molecular marker Saline lacustrine oil Petroleum origin Lower Permian Fengcheng Formation Shallow-buried reservoir Mahu Sag
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Origin of hydrocarbon fluids and discussion of abnormal carbon isotopic compositions in the Lishui-Jiaojiang Sag,East China Sea Shelf Basin
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作者 Jingqi Xu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第3期76-88,共13页
The hydrocarbon gases in the L1 gas field of the Lishui-Jiaojiang Sag have been commonly interpreted to be an accumulation of pure sapropelic-type thermogenic gas.In this study,chemical components,stable isotopic comp... The hydrocarbon gases in the L1 gas field of the Lishui-Jiaojiang Sag have been commonly interpreted to be an accumulation of pure sapropelic-type thermogenic gas.In this study,chemical components,stable isotopic compositions,and light hydrocarbons were utilized to shed light on the origins of the hydrocarbon fluids in the L1gas pool.The hydrocarbon fluids in the L1 gas pool are proposed to be a mixture of three unique components:mid-maturity oil from the middle Paleocene coastal marine Lingfeng source rock,oil-associated(late oil window)gas generated from the lower Paleocene lacustrine Yueguifeng source rock,and primary microbial gas from the paralic deposits of the upper Paleocene Mingyuefeng source rock.Here,for the first time,the hydrocarbon gases in the L1 gas pool are diagnosed as mixed oil-associated sapropelic-type gas and microbial gas via four pieces of principal evidence:(1)The abnormal carbon isotopic distributions of all methane homologues from C_(1)(CH_(4)or methane)to C_(5)(C_(5)H_(12)or pentane)shown in the Chung plot;(2)the diagnostic~(13)C-depleted C_(1)compared with the thermogenic sapropelic-type gas model,whileδ^(13)C_(2)(C_(2)H_(6)or ethane)andδ^(13)C_(3)(C_(3)H_(8)or propane)both fit perfectly;(3)the excellent agreement of the calculated carbon isotopic compositions of the pure thermogenic gas with the results of the thermal simulated gas from the type-II1 kerogen-rich Yueguifeng source rock;and(4)the oil-associated gas inferred from various binary genetic diagrams with an abnormally elevated gas oil ratio.Overall,the natural gases of the L1 gas pool were quantified in this study to comprise approximately 13%microbial gas,nearly 48%oil-associated sapropelic-type gas,and 39%of nonhydrocarbon gas.The microbial gas is interpreted to have been codeposited and entrained in the humic-kerogen-rich Mingyuefeng Formation under favorable lowtemperature conditions during the late Paleocene-middle Eocene.The microbial gas subsequently leaked into the structurally and stratigraphically complex L1 trap with oil-associated sapropelic-type gas from the Yueguifeng source rock during the late Eocene-Oligocene uplifting event.A small amount of humic-kerogen-generated oil in the L1 gas pool is most likely to be derived from the underlying Lingfeng source rock.The detailed geological and geochemical considerations of source rocks are discussed to explain the accumulation history of hydrocarbon fluids in the L1 gas pool.This paper,therefore,represents an effort to increase the awareness of the pitfalls of various genetic diagrams,and an integrated geochemical and geological approach is required for hydrocarbonsource correlation. 展开更多
关键词 origin of hydrocarbons carbon isotope hydrogen isotope light hydrocarbon East China Sea Shelf Basin Lishui-Jiaojiang Sag
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模糊自适应Kalman滤波算法在SINS/DR组合导航的应用
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作者 许建国 周源 王少蕾 《兵工自动化》 北大核心 2024年第9期1-6,共6页
针对里程仪测量误差导致组合导航精度降低的问题,提出基于系统工作状态和滤波器新息状态相结合的模糊自适应算法。根据新息的变化确定模糊规则,修正里程仪输出增益,使新息始终保持在零均值附近,利用修正后的新息修正观测噪声方差,降低... 针对里程仪测量误差导致组合导航精度降低的问题,提出基于系统工作状态和滤波器新息状态相结合的模糊自适应算法。根据新息的变化确定模糊规则,修正里程仪输出增益,使新息始终保持在零均值附近,利用修正后的新息修正观测噪声方差,降低导航定位的偏差。仿真实验结果证明,该算法能够很好地提高组合导航定位的精度。 展开更多
关键词 sinS/DR组合导航 里程仪 模糊自适应算法 KALMAN滤波
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Origin of dolomites in the Permian dolomitic reservoirs of Fengcheng Formation in Mahu Sag,Junggar Basin, NW China
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作者 TANG Yong LYU Zhengxiang +7 位作者 HE Wenjun QING Yuanhua LI Xiang SONG Xiuzhang YANG Sen CAO Qinming QIAN Yongxin ZHAO Xinmei 《Petroleum Exploration and Development》 2023年第1期43-56,共14页
Origin of authigenic dolomites in the dolomitic reservoir of the Permian Fengcheng Formation in the Mahu Sag of Junggar Basin is unclear.Occurrence and genetic evolution of the authigenic dolomites in dolomitic rock r... Origin of authigenic dolomites in the dolomitic reservoir of the Permian Fengcheng Formation in the Mahu Sag of Junggar Basin is unclear.Occurrence and genetic evolution of the authigenic dolomites in dolomitic rock reservoir of the Fengcheng Formation in the Mahu Sag were analyzed by polarized and fluorescence thin sections,scanning electron microscope(SEM),electron microprobe(EMP),C,O and Sr isotopes analysis,and other techniques.(1)Dolomites were mainly precipitated in three stages:penecontemporaneous-shallow burial stage(early stage of the Middle Permian),middle burial stage(middle stage of the Middle Permian),and middle-deep burial stage,with the former two stages in dominance.(2)Dolomitization fluid was high-salinity brine originating from alkaline lake.In the penecontemporaneous-shallow burial stage,Mg^(2+)was mainly supplied by alkaline-lake fluid and devitrification of volcanic glass.In the middle burial stage,Mg^(2+)mainly came from the transformation of clay minerals,devitrification of volcanic glass and dissolution of aluminosilicates such as feldspar.(3)Regular changes of Mg,Mn,Fe,Sr,Si and other elements during the growth of dolomite were mainly related to the alkaline-lake fluid,and to different influences of devitrification and diagenetic alteration of volcanic materials during the burial.(4)In the penecontemporaneous stage,induced by alkaline-lake microorganisms,the micritic-microcrystalline dolomites were formed by primary precipitation,replacement of aragonite and high-Mg calcite,and other processes;in the shallow burial stage,the silt-sized dolomites were formed by continuous growth of micritic-microcrystalline dolomite and replacement of calcites,tuffs and other substances;in the middle burial stage,the dolomites,mainly silt-and fine-sized,were formed by replacement of volcanic materials.The research results are referential for investigating the formation mechanism and distribution patterns of tight dolomitic reservoirs in the Mahu Sag and other similar oil and gas bearing areas. 展开更多
关键词 dolomitic rock dolomite origin tight oil reservoir Permian Fengcheng Formation Mahu Sag Junggar Basin fluid source fluid evolution isotopic composition
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基于双通道Residual-LSTM的SINS/GNSS组合导航算法
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作者 奔粤阳 王奕霏 +2 位作者 李倩 魏廷枭 周一帆 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第4期325-333,共9页
针对全球导航卫星系统信号中断情况下SINS/GNSS组合导航系统无法持续进行误差校正的问题,提出一种基于双通道Residual-LSTM的SINS/GNSS组合导航算法。首先,考虑到SINS经度、纬度误差传播特性不同所导致的模型输入、输出信息之间的非线... 针对全球导航卫星系统信号中断情况下SINS/GNSS组合导航系统无法持续进行误差校正的问题,提出一种基于双通道Residual-LSTM的SINS/GNSS组合导航算法。首先,考虑到SINS经度、纬度误差传播特性不同所导致的模型输入、输出信息之间的非线性相关性差异化,构建具有不同权重系数的双通道长短期记忆神经网络模型结构,并引入遗忘信息共享机制自适应地利用历史导航数据对经度、纬度信息进行拟合预测。其次,针对深层神经网络存在的模型退化和梯度消失问题,在多层双通道LSTM网络之间建立残差高速通道形成Residual-LSTM模型结构,以增加不同网络层次之间的信息传播路径。最后,通过实船数据验证本文所提算法的有效性。实验结果表明,与基于常规智能方法的SINS/GNSS组合导航算法相比,所提组合导航算法在GNSS信号中断期间经度误差降低了51.97%,纬度误差降低了31.45%。 展开更多
关键词 sinS/GNSS组合导航 GNSS中断 双通道结构 残差长短期记忆神经网络 深度神经网络
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Corrigendum to "Role of remote sensing,geographic bioinformatics system and bioinformatics in kala-azar epidemiology" [originally published as J Biomed Res 2011,25(6):373-384;doi:10.1016/S1674-8301(11)60050-X] 被引量:2
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作者 Gouri Sankar Bhunia Manas Ranjan Dikhit +2 位作者 Shreekant Kesari Ganesh Chandra Sahoo Pradeep Das 《The Journal of Biomedical Research》 CAS 2012年第5期371-371,共1页
The author would like to inform the readers that the correct form of title "Role of remote sensing, geographic bioinformatics system and bioinformatics in kala-azar epidemiology" , content in ab-stract "The computa... The author would like to inform the readers that the correct form of title "Role of remote sensing, geographic bioinformatics system and bioinformatics in kala-azar epidemiology" , content in ab-stract "The computational approaches like remote sensing, geographic information system (GIS) and bioinformatics are the key re-sources for the detection and distribution of vectors, patterns, ecologi- cal and environmental factors and genomic and proteomic analysis.", and keyword "geographical bioinformatics systems (GIS)" should be read as follows: title "Role of remote sensing, geographical bioinformation system and bioinformatics in kala-azar epidemiology", content in abstract "The com-putational approaches like remote sensing, geographical information system (GIS) and bioinformat-ics are the key re-sources for the detection and distribution of vectors, patterns, ecological and envi-ronmental factors and genomic and proteomic analysis.", and keyword "geographical bioinformation system (GIS) ". 展开更多
关键词 originally published as J Biomed Res 2011 25 GIS Corrigendum to Role of remote sensing geographic bioinformatics system and bioinformatics in kala-azar epidemiology
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