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刚果盆地钾盐矿床地震反射波特征与沉积规律

地球物理学进展 2016年第6期31卷 2641-2648页

作者：宋鹏宋希利田明阳中国地质科学院地质研究所北京100037 中国地质大学北京100083 山东省地矿工程勘察院济南250013 山东省第一地质矿产勘查院济南250013

中国是钾盐资源缺乏的国家,国内需求主要依靠进口,寻求和开发国外钾盐资源是保证国内需求的重要途径,刚果钾盐资源勘探是中国在国外勘探和开发项目之一,位于刚果成盐盆地的中部.刚果盆地是世界上典型的裂谷型盆地之一,其钾盐资源丰富,... 详细信息

中国是钾盐资源缺乏的国家,国内需求主要依靠进口,寻求和开发国外钾盐资源是保证国内需求的重要途径,刚果钾盐资源勘探是中国在国外勘探和开发项目之一,位于刚果成盐盆地的中部.刚果盆地是世界上典型的裂谷型盆地之一,其钾盐资源丰富,钾盐矿床形成于白垩世,属典型的海相蒸发沉积矿床,经过沉积、沉积淋滤改造和埋藏—变质改造作用形成了具有大规模的矿(层)床.对该区钾盐矿床的勘探采用地质调查、物探和钻探相结合的方法进行,其中物探以地震反射波勘探为主,其解释成果对指导钻探布孔和找矿发挥了极其重要作用.对地震资料采用国内外先进的叠前深度偏移处理技术,使深层地震信号频率低、能量弱、信噪比低及子波畸变大等问题得到了有效改善,妥善解决了深层速度分析和偏移成像问题.本次勘探重点是对中部盐类沉积层位即新近系、白垩系沉积层进行划分,圈出其顶底界面和矿层平面位置与厚度.通过钻孔验证发现了厚度大的钾盐矿(层),最后经综合分析研究各种资料将盐系地层划分为四个矿带并圈定了钾盐矿30层,确定为特大型矿床.对本矿床的成功发现,有必要进行探讨和总结.

关键词：地震勘探钾盐矿床沉积规律刚果盆地

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CAP1400蒸汽发生器汽水分离装置研究

原子能科学技术 2016年第12期50卷 2194-2199页

作者：应秉斌林绍萱宋印玺尤岩上海核工程研究设计院上海200233

汽水分离装置是蒸汽发生器中的主要部件,其性能不仅会影响蒸汽发生器水力循环特性及水位适用性,决定上部尺寸大小,而且会影响汽轮机的正常运行。对CAP1400核电厂蒸汽发生器汽水分离装置进行了不同蒸汽负荷、饱和水量及高水位和正常水位... 详细信息

汽水分离装置是蒸汽发生器中的主要部件,其性能不仅会影响蒸汽发生器水力循环特性及水位适用性,决定上部尺寸大小,而且会影响汽轮机的正常运行。对CAP1400核电厂蒸汽发生器汽水分离装置进行了不同蒸汽负荷、饱和水量及高水位和正常水位等试验工况下的热态性能试验,获得了SP3型初级分离器与P3X型干燥器组合随蒸汽负荷、饱和水量、水位变化的分离特性。通过初级分离器和干燥器的阻力测量,分别获得了分离器和干燥器的阻力特性,对CAP1400蒸汽发生器的设计研发起到支撑作用。

关键词：核电厂蒸汽发生器汽水分离干燥器热态性能试验螺旋叶片

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基于消费维度的幸福考量:国外的研究动态

消费经济 2017年第5期33卷 91-96,F0003页

作者：宋鑫刘希琼湖南师范大学商学院湖南长沙410081

随着我国即将全面建成小康社会,消费需求上升规律作用下的居民消费质量不断提高,人们对幸福的追求势必成为热议和行动。在此背景下,为推进国内相关研究与实践,论文基于消费维度,对国外的幸福研究文献进行了梳理。结果发现,相关研究主要... 详细信息

随着我国即将全面建成小康社会,消费需求上升规律作用下的居民消费质量不断提高,人们对幸福的追求势必成为热议和行动。在此背景下,为推进国内相关研究与实践,论文基于消费维度,对国外的幸福研究文献进行了梳理。结果发现,相关研究主要集中在收入、财富、消费与幸福,消费支出类别与幸福,享乐消费与幸福,炫耀性、奢侈性消费与幸福,亲社会消费与幸福,体验型消费与幸福等方面。最后,论文从研究对象、研究方法、研究视角、研究结论上对前述研究成果进行了简要评价。

关键词：消费幸福国外研究动态

Single-cell characterization of major components of plant cell walls in situ by Raman spectroscopy

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Science China(Life Sciences) 2024年第8期67卷 1772-1774页

作者： Yujian Li Weiwei Shen xi Zhang Yaning Cui Yuanyuan Zhao Yayu Guo xiaojuan Li Shuizhong Wang Guoyong song Pu Wang Jianfeng Ma Jinxing Lin State Key Laboratory of Efficient Production of Forest Resources College of Biological Sciences and TechnologyBeijing Forestry UniversityBeijing 100083China Institute of Tree Development and Genome Editing Beijing Forestry UniversityBeijing 100083China National Engineering Research Center of Tree Breeding and Ecological Restoration College of Biological Sciences and TechnologyBeijing Forestry UniversityBeijing 100083China Beijing Key Laboratory of Lignocellulosic Chemistry Engineering Research Center of Forestry Biomass Materials and EnergyMinistry of EducationBeijing Forestry UniversityBeijing 100083China Beijing Advanced Innovation Center for Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityBeijing 100191China Key lab of Bamboo and Rattan Science&Technology International Center for Bamboo and RattanBeijing 100102China

Dear Editor,Plant cell walls are complex and dynamic structures that are mainly composed of polysaccharide polymers such as cellulose,hemicellulose,and pectin,in addition to substantial amounts of the non-saccharide polymer lignin(McFarlane et al.,2014;German et al.,2023).The components of cell walls are interconnected in various ways to form a complex,multilayered network structure(Wen et al.,2023).

关键词： walls cellulose characterization

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河流生态环境需水量研究综述

水土保持学报 2003年第6期17卷 95-97,113页

作者：宋进喜李怀恩王伯铎西安理工大学水利水电学院陕西西安710048 西北大学环境科学系陕西西安710069

在全面总结国内外河流生态环境需水量研究进展的基础上,对有关河流生态环境需水研究的概念、内容和定量计算方法做了概述,指出了目前河流生态环境需水研究中存在的主要问题并进行了分析。

关键词：河流生态环境需水

Experimental study on combustion characteristics of supersonic combustor based on alternating-wedge strut

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Chinese Journal of Aeronautics 2024年第5期37卷 214-227页

作者： Jie LI Wenyan song Yuhang WANG School of Power Energy Northwestern Polytechnical UniversityXi’an 710129China

Acetone Planar Lase-Induced Fluorescence(PLIF)and OH-PLIF were employed to capture the fuel distribution and OH distribution downstream for the supersonic combustor based on the alternating-wedge *** combustion establishment process and combustion mode in the combustor under different fuel injection methods and different equivalence ratios were *** with the kerosene-PLIF and OH-PLIF results in the cavity combustor,a comparative analysis was conducted to understand the combustion characteristics and combustion modes between the alternating-wedge strut-based combustor and the cavity-based *** results show that the combustor is in weak combustion mode in the case of low equivalence ratio,and the combustor is in intensive combustion mode in the case of high equivalence *** lower limit of the equivalence ratio of the combustor to maintain the intensive combustion mode varies based on different fuel injection *** OH distribution under reacting condition has a strong correlation with the fuel distribution under non-reacting *** OH fluorescence signal near the injector is weaker when the fuel distribution is more *** injector position located at the base of the strut rear has better mixing performance,enabling the combustor to be in intensive combustion mode at a lower equivalence *** combustion reaction in the alternating-wedge strut-based combustor is not necessarily dominated by mass transfer due to the mixing enhancement and premixed zone downstream of strut,while the combustion reaction process in the cavity-based combustor is mainly influenced by mass transfer.

关键词： Supersonic combustor Alternating-wedge strut Cavity PLIF Fuel injection Fuel distribution Combustion characteristics Combustion mode

Differences in symptoms and pre-hospital delay among acute myocardial infarction patients according to ST-segment elevation on electrocardiogram: an analysis of China Acute Myocardial Infarction (CAMI) registry

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Chinese Medical Journal 2019年第5期132卷 519-524页

作者： Rui Fu Chen-xi song Ke-Fei Dou Jin-Gang Yang Hai-Yan Xu xiao-Jin Gao Qian-Qian Liu Han Xu Yue-Jin Yang Department of Cardiology Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background: Approximately 70% patients with acute myocardial infarction (AMI) presented without ST-segment elevation on electrocardiogram. Patients with non-ST segment elevation myocardial infarction (NSTEMI) often presented with atypical symptoms, which may be related to pre-hospital delay and increased risk of mortality. However, up to date few studies reported detailed symptomatology of NSTEMI, particularly among Asian patients. The objective of this study was to describe and compare symptoms and presenting characteristics of NSTEMI vs. STEMI patients. Methods: We enrolled 21,994 patients diagnosed with AMI from China Acute Myocardial Infarction (CAMI) Registry between January 2013 and September 2014. Patients were divided into 2 groups according to ST-segment elevation: ST-segment elevation (STEMI) group and NSTEMI group. We extracted data on patients' characteristics and detailed symptomatology and compared these variables between two groups. Results: Compared with patients with STEMI (N=16,315), those with NSTEMI (N=5679) were older, more often females and more often have comorbidities. Patients with NSTEMI were less likely to present with persistent chest pain (54.3% vs.71.4%), diaphoresis (48.6% vs.70.0%), radiation pain (26.4% vs.33.8%), and more likely to have chest distress (42.4% vs.38.3%) than STEMI patients (all P<0.0001). Patients with NSTEMI were also had longer time to hospital. In multivariable analysis, NSTEMI was independent predictor of presentation without chest pain (odds ratio: 1.974, 95% confidence interval:1.849-2.107). Conclusions: Patients with NSTEMI were more likely to present with chest distress and pre-hospital patient delay compared with patients with STEMI. It is necessary for both clinicians and patients to learn more about atypical symptoms of NSTEMI in order to rapidly recognize myocardial infarction.

关键词： Non-ST segment elevation myocardial infarction Symptom assessment Time to treatment

人民币汇率、中国外汇储备与货币错配——基于理论和实证研究

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山西财经大学学报 2009年第9期31卷 103-109页

作者：张细松朱新蓉中南财经政法大学新华金融保险学院湖北武汉430060 山东经济学院财政金融学院山东济南250014

与多数发展中国家不同,人民币升值使中国的货币错配问题较为严重,持有大量外汇储备是解决货币错配问题的有效方法。人民币汇率和中国外汇储备不存在长期的稳定均衡关系,人民币升值是中国外汇储备增长的格兰杰原因,而中国外汇储备增长并... 详细信息

与多数发展中国家不同,人民币升值使中国的货币错配问题较为严重,持有大量外汇储备是解决货币错配问题的有效方法。人民币汇率和中国外汇储备不存在长期的稳定均衡关系,人民币升值是中国外汇储备增长的格兰杰原因,而中国外汇储备增长并不是人民币升值的格兰杰原因。要真正解决中国的货币错配问题,必须进行一系列的综合配套改革。

关键词：货币错配人民币汇率外汇储备汇率制度

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油气生产井中瞬变电磁法接收技术研究

西北大学学报（自然科学版） 2012年第6期42卷 890-896页

作者：郭宝龙宋汐瑾西安电子科技大学智能控制与图像工程研究所陕西西安710071

目的研究瞬变电磁法应用于油气生产井测井领域时,接收线圈的瞬变电磁响应特征,为生产井瞬变电磁法接收线圈的参数设计提供理论依据。方法通过对井中接收线圈等效电路的理论分析,详细讨论了斜阶跃波激励下,接收线圈上一次场与二次场的变... 详细信息

目的研究瞬变电磁法应用于油气生产井测井领域时,接收线圈的瞬变电磁响应特征,为生产井瞬变电磁法接收线圈的参数设计提供理论依据。方法通过对井中接收线圈等效电路的理论分析,详细讨论了斜阶跃波激励下,接收线圈上一次场与二次场的变化规律,深入研究了井中全程瞬变电磁响应的过渡过程及其影响因素。结果接收线圈过渡过程的存在,使一次场响应在感应段和衰减段均发生了畸变,而二次响应则在发射电流关断后出现幅值变小、达到极大值的时间延迟等现象。为缩短线圈的固有过渡过程,应采用接入匹配电阻的方法使接收线圈工作于临界阻尼状态,同时尽量增大线圈的阻尼系数。结论该方法为井中瞬变电磁响应信号的正确判断与识别奠定了良好基础。

关键词：瞬变电磁法接收线圈过渡过程阻尼系数