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Paleoenvironment controls on organic matter accumulation in transitional shales from the eastern Ordos Basin,China

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Frontiers of Earth Science 2021年第4期15卷 737-753页

作者： jianwei lv Songhang ZHANG Ning YANG Chunbo FU Xinlu YAN Yang LI School of Energy Resources China University of GeosciencesBeijing 100083China Chinese Academy of Natural Resources Economics Beijing 101149China Huadian Coal Industry Group Co. Ltd.Beijing 100035China Second Oil Production Plant PetroChina Changqing Oilfield CompanyQingyang 745100China

To investigate the paleoenvironmental controls on organic matter accumulation of Upper Paleozoic shales in the eastern Ordos Basin,China,26 shale samples were collected from two wells drilled into the Shanxi and Taiyuan Formations.The total organic carbon(TOC)content,mineral compositions and elemental geochemistry of the samples were analyzed.Quartz(35.42%)and clay minerals(48.34%)are the dominant minerals and trace elements(Li,Cs,Cu,V,Co,and Cr)are commonly enriched in the shale samples compared to the Upper Continental Crust.C-values(ranging from 0.2 to 4.5),chemical indices of weathering(CIW)values(48.82 to 99.11),and Sr/Cu ratios(1.00 to 11.05)suggest that the paleoclimate was humid in the study area during the Late Paleozoic.Elemental redox indices(e.g.,Al_(2)O_(3)/(Al_(2)O_(3)+Fe_(2)O_(3)),V/Cr,Ni/Co,V/(V+Ni)and U/Th)indicate a dysoxic to oxic paleoenvironment characterized by transi-tional sedimentary deposits in a continental margin setting.In addition,chemical index of alteration(CIA,ranging from 77.92%to 98.36%)and CIW(89.19%to 99.11%)values suggest that there was intense chemical weathering in the study area,while the Al_(2)O_(3)-CaO^(*)+Na_(2)O-K_(2)O(A-CN-K)ternary diagram demonstrates that the shales were not subjected to potassium metasomatism during diagen-esis.Al_(2)O_(3)/TiO_(2)and TiO_(2)/Zr ratios,as well as REE characteristics suggest a felsic source rocks and discount seawater as an REE source.Ce anomalies indicate an oxic environment with terrigenous input during black shale deposition,and LREE enrichment with negative Eu anomalies suggests that both shale formations were affected by detrital input rather than hydrothermal fluids.The correlation of TOC(ranging from 1.10%to 6.39%,with an average of 2.77%)with trace elemental redox indices(Sr/Cu,Sr/Ba,V/Cr,and U/Th)indicates that a warm-humid,dysoxic to oxic environment preserved much of the organic matter.

关键词： Late Paleozoic shale geochemistry paleoenvironment eastern Ordos Basin

Development and validation of simple sequence repeat markers from Arachis hypogaea transcript sequences

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The Crop Journal 2018年第2期6卷 172-180页

作者： Houmiao Wang Yong Lei Liying Yan Liyun Wan Yan Cai Zefeng Yang jianwei lv Xiaojie Zhang Chenwu Xu Boshou Liao Key Laboratory of Oil Crop Biology of the Ministry of Agriculture CAAS-ICRISAT Joint Laboratory for Groundnut Aflatoxin ManagementOil Crops Research Institute of Chinese Academy of Agricultural SciencesWuhan 430062HubeiChina Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops Key Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhou 225009ZhejiangChina

Simple sequence repeats(SSRs) are important molecular markers for assessing genetic diversity in Arachis hypogaea L. and many other crops and constructing genetic linkage maps for important agricultural traits. In this study, 29,357 potential SSRs were identified in 22,806 unigenes assembled from A. hypogaea transcript sequences. Of these unigenes, 1883 and 4103 were annotated and assigned in Kyoto Encyclopedia of Genes and Genomes Orthology and Eukaryotic Orthologous Groups databases, respectively. Among the SSR motifs, mono-(19,065; 64.94%) and trinucleotide(5033; 17.14%) repeats were the most common, and the three most dominant motifs were A/T(18,358; 62.54%), AG/CT(2804;9.55%), and AAG/CTT(1396; 4.76%). Polymerase chain reaction(PCR) primer pairs were designed for 4340 novel SSR markers and 210 new SSRs were validated using 24 A. hypogaea varieties. Of the 210, 191(91%) yielded PCR products, with 37(18%) identifying polymorphisms. The 37 polymorphic SSR markers detected 146 alleles(2–10 alleles per locus), and the average polymorphic information content was 0.403(with a range of 0.077 to0.819). The new SSRs enrich the current marker resources for A. hypogaea and may also be useful for genetic diversity analysis, functional genomics research, and molecular breeding.

关键词： Arachis hypogaea L Molecular marker Polymorphism SSR

FPSO海水压载舱涂层系统及锌合金牺牲阳极阴保系统失效分析和解决方案

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涂层与防护 2024年第2期45卷 23-28页

作者：张国庆吕建伟熊睿周迎春海洋石油工程股份有限公司天津300451

分析了大于50℃条件下海洋石油工程FPSO海水压载防腐涂层失效及阴极保护失效的原因。基于高温环境下锌合金牺牲阳极的失效原因分析、涂层失效分析,结合阳极接触电阻测量、阳极材料化学成分分析、腐蚀产物分析(钝化层)以及对其实际使用... 详细信息

分析了大于50℃条件下海洋石油工程FPSO海水压载防腐涂层失效及阴极保护失效的原因。基于高温环境下锌合金牺牲阳极的失效原因分析、涂层失效分析,结合阳极接触电阻测量、阳极材料化学成分分析、腐蚀产物分析(钝化层)以及对其实际使用环境的模拟等手段,确认导致该环境下防腐涂层失效及牺牲阳极阴保系统失效的主要原因,为该使用环境下的防腐设计和阳极材料选择提供风险分析,避免类似失效风险,避免由于该问题引发的停产及重大安全事故。

关键词：压载舱锌阳极失效原因分析极性反转浮式生产储油装置

Nonvolatile and reconfigurable two-terminal electro-optic duplex memristor based on III-nitride semiconductors

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Light(Science & Applications) 2024年第4期13卷 706-716页

作者： Zhiwei Xie Ke Jiang Shanli Zhang jianwei Ben Mingrui Liu Shunpeng lv Yang Chen Yuping Jia Xiaojuan Sun Dabing Li State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesDongnanhu Road No.3888Changchun 130033China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesYuquan Road No.19100049 BeijingChina These authors contributed equally:Zhiwei XieKe Jiang

With the fast development of artificial intelligence(AI),Internet of things(IOT),etc,there is an urgent need for the technology that can efficiently recognize,store and process a staggering amount of information.The AlScN material has unique advantages including immense remnant polarization,superior temperature stability and good latticematch to other III-nitrides,making it easy to integrate with the existing advanced III-nitrides material and device technologies.However,due to the large band-gap,strong coercive field,and low photo-generated carrier generation and separation efficiency,it is difficult for AlScN itself to accumulate enough photo-generated carriers at the surface/interface to induce polarization inversion,limiting its application in in-memory sensing and computing.In this work,an electro-optic duplex memristor on a GaN/AlScN hetero-structure based Schottky diode has been realized.This twoterminal memristor shows good electrical and opto-electrical nonvolatility and reconfigurability.For both electrical and opto-electrical modes,the current on/off ratio can reach the magnitude of 104,and the resistance states can be effectively reset,written and long-termly stored.Based on this device,the“IMP”truth table and the logic“False”can be successfully reproduced,indicating the huge potential of the device in the field of in-memory sensing and computing.

关键词： polarization duplex limiting

Saw Palmetto-Based Nutritional Supplement Prostataplex Relieves Symptoms of Benign Prostatic Hyperplasia (BPH) in Patients with Mild to Moderate BPH

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Open Journal of Urology 2012年第3期2卷 104-108页

作者： Qingwen Xie Jing Leng jianwei lv Allan Pantuck Lawrence Yen Mina Shariff Kenneth Kami Jianyu Rao Rong Shi Department of Pathology and Laboratory Medicine David Geffen School of Medicine University of California Los Angeles USA Department of Preventive Medicine School of Public Health Shanghai Jiao Tong University School of Medicine Shanghai China Department of Research DRM Resources Costa Mesa USA Department of Urology David Geffen School of Medicine University of California Los Angeles USA Department of Urology Shanghai Renji Hospital Shanghai Jiao Tong University School of Medicine Shanghai China

The goal of this study was to assess the efficacy of the saw palmetto-based nutritional supplement, Prostataplex, for relieving the symptoms associated with benign prostatic hyperplasia (BPH) in men with mild to moderate degrees of BPH. A randomized, double-blind, placebo-controlled trial was performed in Shanghai, China. Eighty patients with BPH were randomly assigned to either the intervention group (39 cases) or control group (41 cases). Patients in the intervention group were administered Prostataplex orally and placebos were given to patients in the control group. The duration of treatment was 12 weeks in both groups. Following the intervention of Prostataplex, the maximum urinary flow rates (MFR), total scores of International Prostate Symptom Score (IPSS) and quality of life indicators were significantly better among the patients in the intervention group than those in the control group (P < 0.01 for all variables). Significant improvement of symptoms including dysuria, reducing nocturnal polyuria and increasing urinary flow rate was seen after two months of intervention, especially for the improvement of incomplete bladder emptying. Prostataplex has positive effects on improving symptoms as well as quality of life in men with mild to moderate BPH.

关键词： Saw Palmetto Prostataplex Benign Prostatic Hyperplasia Intervention

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图像去雾方法质量评价

光学精密工程 2022年第6期30卷 721-733页

作者：韩昊男钱锋吕建威张葆中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100049

针对近年来去雾算法质量的评价方法普遍依赖主观评价结果,但缺乏定量描述;现有的客观质量评价方法与主观评价方法之间的一致性不稳定,使两者有时会出现分歧的问题。为提升针对去雾方法的客观质量评价性能,本文提出了一种基于人工合成图... 详细信息

针对近年来去雾算法质量的评价方法普遍依赖主观评价结果,但缺乏定量描述;现有的客观质量评价方法与主观评价方法之间的一致性不稳定,使两者有时会出现分歧的问题。为提升针对去雾方法的客观质量评价性能,本文提出了一种基于人工合成图像的全参考去雾方法质量评价。首先,建立合成图像数据集,数据集包括参考无雾图像,合成有雾图像,对这些合成有雾图像使用8种主流去雾算法得到的去雾图像。然后,将去雾后图像可能引入的一些质量问题进行分类。最后,通过结合清晰度相关特征和现有的客观质量评价,针对性地提出了一种由图像可视性、结构相似性和颜色恢复度相互融合的去雾方法质量评价。在合成图像数据集中,将本文方法与现有典型的图像质量评价方法进行对比实验,实验结果表明:对于合成图像数据集,本文提出的方法在SRCC、PLCC和RMSE指标上表现最优。本文方法与主观评价的一致性更高,更有利于支持去雾算法的研究。

关键词：图像去雾客观质量评价合成有雾图像图像数据集

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人类胚胎研究“14天规则”的挑战与出路

自然辩证法通讯 2022年第10期44卷 77-86页

作者：彭耀进吕建伟中国科学院动物研究所北京100101 北京干细胞与再生医学研究院北京100101

近年来,随着生命科技迅猛发展,人类胚胎研究“14天规则”正面临巨大挑战。是否延长“14天规则”已成为当今国际社会人类胚胎研究领域伦理、政策争议焦点之一。支持者与反对者在科学支撑和伦理论证方面难以调和。本文通过对“14天规则”... 详细信息

近年来,随着生命科技迅猛发展,人类胚胎研究“14天规则”正面临巨大挑战。是否延长“14天规则”已成为当今国际社会人类胚胎研究领域伦理、政策争议焦点之一。支持者与反对者在科学支撑和伦理论证方面难以调和。本文通过对“14天规则”争议深入剖析,展现科学支撑、伦理论证和公众探讨之本质问题,考察该规则产生的深层原因、伦理蕴含,指出其得以确立之最大经验在于独立的调查机构和广泛的公众探讨。本文认为“14天规则”之改变应以审慎为原则,在理清科学和伦理问题基础上,寻求强科学理由和强伦理支撑,通过广泛公众探讨达成一定程度的共识,同时配以适当监管政策,并积极寻求新的国际共识形成。

关键词：胚胎研究 14天规则伦理问题沃诺克报告

An Accelerated Simulation Assessment Approach for Mission Success Probability of Multi-State Phased Mission Systems

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An Accelerated Simulation Assessment Approach for Mission Su...

河北省新建本科院校双师双能型教师培养途径研究

第32届中国控制与决策会议

作者： Yang Haojie lv jianwei Xu Yifan Department of Management Engineering and Equipment Economics Naval University of Engineering

ISBN: (数字)9781728158556

ISBN: (纸本)9781728158563

The mission success probability assessment of multi-state phased mission systems（MS-PMS） under complex mission were studied.A general simulation framework of the system under complex mission based on discrete event simulation is established.The Monte Carlo method is used to generate the sample of random events,and accelerated sampling methods such as forced transitions and failure biasing are added to improve the sampling efficiency of small probability events,and the sampling statistics are modified to ensure the unbiasedness of the estimates.Taking the warship navigation mission as an example,it is found that the accelerated sampling method can effectively improve the sampling probability of small probability events in the mission regardless of the mission time.The main reason for the failure of the mission can be found by this simulation method,which can provide a basis for improving the success probability of the mission.

关键词： Mission success probability Multi-state system Monte Carlo method Warship navigation mission

来源： cnki会议评论

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河北能源职业技术学院学报 2022年第2期22卷 1-4页

作者：卢昆吕健伟河北环境工程学院河北秦皇岛066102

新建本科院校因师资基础薄弱,教师教学压力大,双师双能型教师的培养一直都是师资培养的难点。针对新建本科院校双师双能型教师师资缺乏这一问题,依据教育部高等教育质量监测数据平台中对双师型教师的界定原则,结合新建本科实际,提出培... 详细信息

新建本科院校因师资基础薄弱,教师教学压力大,双师双能型教师的培养一直都是师资培养的难点。针对新建本科院校双师双能型教师师资缺乏这一问题,依据教育部高等教育质量监测数据平台中对双师型教师的界定原则,结合新建本科实际,提出培养双师双能型教师的有效途径和方法。

关键词：新建本科双师双能型培养途径