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Discovery and Significance of Malan Loess on the Piedmont Plain in Pinggu District, Beijing

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Acta Geologica Sinica(English Edition) 2014年第5期88卷 1565-1578页

作者： LU Lu ZHAO Yuanyi WANG Xiaoliang ZHAO Xitao YANG Zhenjing WANG Chengmin bi zhiwei LU Wenhui Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing Institute of Geology Liaoning Institute of Geology and Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences No.3 Geology and Mineral Exploration Institute of Gansu Provincial Bureau of Geology and Mineral

The platforms on both sides of the Malangou River （a lateral ditch of the Qingshui River that is a tributary of the Yongding River） where Malan Village in Zhaitang Town of Mentougou District of Beijing is located are the place of China＇s typical section of the Quaternary Malan loess. During the investigation in the eastern suburbs of Beijing City, the authors not only clarified 5 grades of terraces on the Pinggu piedmont plain, but also found a clayey silt section mixed with a small amount of alluvial-diluvial gravel layers at a height of 15-25 m above the river level near a Fishpond in Xinli Village of Nandule Town. Results of the study of grain size of the section document that the loess mostly is silty soil （0.05--0.005 mm）, and that the grain size probability cumulative curves of the section are dominated by single-peak, coarse-grained segment I and coarse-grained segment II types, reflecting that its depositional environment is similar to eolian phase. Identification results of heavy minerals from the section show that their contents account for 0.01%-0.11%, averaging 0.04%. There are 24 kinds of heavy minerals, most of which are stable heavy minerals, and the clay minerals mostly are illite, which is consistent with the Malan loess on the Loess Plateau. The chemical composition data reflect that the source area of the loess is relatively arid. The six grade classification of sporopollen in the section further shows the subdivision of the history of alternating warm and humid phases in this geological period. The thermoluminescence dating results range from 21.0 ka to 59.2 ka, convincingly demonstrating that the section indeed consists of Malan loess. The above studies provide a new basis for overall understanding of the distribution of the Malan loess at the northeast margin of the North China Plain and its environment change in the Late Pleistocene.

关键词： eolian loess Malan loess formation environment Pinggu

The effects of proton irradiation on the electrical properties of NbAlO/AlGaN/GaN MIS-HEMT

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Science China(Physics,Mechanics & Astronomy) 2012年第1期55卷 40-43页

作者： bi zhiwei FENG Qian ZHANG JinCheng LU Ling MAO Wei GU WenPing MA XiaoHua HAO Yue Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices School of Microelectronics Xidian University Xi＇an 710071 China

AlGaN/GaN metal-insulator-semiconductor high electron-mobility transistors （MIS-HEMTs） with atomic layer deposited （ALD） NbA10 gate dielectric were investigated using 3 MeV proton irradiation at a fluence of 1015 p/crn2. It was found that the proton irradiation damage caused degradation in DC performance and a flatband voltage shift in the capacitance-voltage curve. Gate-drain conductance measurements indicated that new traps were introduced in GaN from the irradiation, and the trap densities increased from 1.18×10^12 ***-1 to 1.82×10^12 ***-1 in MIS-HEMTs after irradiation. However, these increases in trap densities caused by irradiation in MIS-HEMT are less than those in HEMT, which can be attributed to the protection of the A1GaN surface by the NbA10 dielectric layer.

关键词： AIGaN/GaN MIS-HEMT proton irradiation trap

河北围场河西村钼矿床流体包裹体和同位素特征

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中国钼业 2024年第2期48卷 9-16页

作者：贾立民毕志伟刘腾飞王强赵泽南河北省区域地质调查院河北廊坊065000

河西村钼矿床是近年来新发现的斑岩型钼矿床,矿体赋存于石英二长斑岩体之中,其形成年龄为136.6 Ma,碱长花岗斑岩侵入并破坏了含矿石英二长斑岩的岩石和矿体特征,其形成年龄为129.8 Ma,研究区斑岩型钼矿床的成矿年龄为129.8~136.6 Ma。... 详细信息

河西村钼矿床是近年来新发现的斑岩型钼矿床,矿体赋存于石英二长斑岩体之中,其形成年龄为136.6 Ma,碱长花岗斑岩侵入并破坏了含矿石英二长斑岩的岩石和矿体特征,其形成年龄为129.8 Ma,研究区斑岩型钼矿床的成矿年龄为129.8~136.6 Ma。流体包裹体研究表明:包裹体以富液两相水溶液包裹体为主,均一温度范围为244.7~388.1℃,盐度为0.33%~4.55%,流体密度为0.48~0.83 g/cm^(3),均一压力为3.2~24 MPa,含矿石英脉为D脉,形成于石英二长斑岩岩浆活动晚期。

关键词：钼矿斑岩型流体包裹体成矿时代

干预图在卵巢癌腹腔镜手术护理中的应用效果研究

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齐齐哈尔医学院学报 2024年第6期45卷 593-597页

作者：毕志伟师凯歌王子博韩笑赵要松郑州大学第三附属医院手术室河南郑州450000

目的探究干预图在卵巢癌腹腔镜手术护理中的应用效果。方法选择2020年1月—2022年12月在本院行卵巢癌腹腔镜手术的62例患者作为研究对象,随机分为观察组(基于干预图护理)和对照组(常规手术护理)两组,每组各31例。比较两组手术配合度、... 详细信息

目的探究干预图在卵巢癌腹腔镜手术护理中的应用效果。方法选择2020年1月—2022年12月在本院行卵巢癌腹腔镜手术的62例患者作为研究对象,随机分为观察组(基于干预图护理)和对照组(常规手术护理)两组,每组各31例。比较两组手术配合度、手术相关指标、不良情绪、并发症情况及康复进程。结果与对照组相比,观察组手术间布局合理、仪器设备使用方便、手术体位对操作影响小、器械摆台合理、器械传递更准确、器械传递及时、医护配合得分更高(P0.05)。观察组护理后焦虑自评量表(SAS)和抑郁自评量表(SDS)得分低于对照组(P<0.05)。观察组并发症发生率(6.45%)低于对照组(25.81%)(P<0.05)。观察组恢复正常饮食时间、开始自行洗漱时间、术后切口疼痛消失时间及开始正常活动时间更短(P<0.05)。结论卵巢癌腹腔镜手术护理采用干预图可提高手术配合度,改善患者手术相关指标,减少并发症,还能促进康复进程。

关键词：干预图卵巢癌腹腔镜手术护理手术配合度生活质量

The passivation mechanism of nitrogen ions on the gate leakage current of HfO_2/AlGaN/GaN MOS-HEMTs

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Science China(Physics,Mechanics & Astronomy) 2011年第12期54卷 2170-2173页

作者： bi zhiwei HAO Yue FENG Qian JIANG TingTing CAO YanRong ZHANG JinCheng MAO Wei LU Ling ZHANG Yue Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices School of Microelectronics Xidian University Xi＇an 710071 China State Key Laboratory of ASIC and System School of Microelectronics Fudan University Shanghai 200433 China School of Electronical ＆ Mechanical Engineering Xidian University Xi＇an 710071 China

In this paper, we systematically study the positive gate leakage current in AlGaN/GaN metal-oxide-semiconductor high electron-mobility transistors (MOS-HEMTs) with HfO 2 dielectric using atomic layer deposition (ALD). We observe that the incorporated nitrogen ions will improve the positive gate leakage current of devices obviously, but do not change the reverse gate leakage current. The passivation mechanism of nitrogen ions in oxygen vacancies in HfO 2 is studied by first-principles calculations. It is shown that the gap states of HfO 2 caused by oxygen vacancies increase the positive gate leakage current of MOS-HEMTs. Nitrogen ions passivate the gap states of HfO 2 and decrease the positive gate leakage current but do not effect the reverse gate leakage current.

关键词： AlGaN/GaN MOS-HEMT passivation gate leakage current nitrogen ions

基于电力现货市场的零售分时用户结算模式研究

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电力大数据 2024年第3期27卷 79-87页

作者：陆春阳王潇炜范凯迪成慧娟毕志为国网山西省电力公司营销服务中心山西太原030000

该文探讨了在电力市场发展中,中长期交易与现货交易如何实现有效衔接以及分时段交易的重要作用。文章通过引入分时电价机制,阐述了如何引导用户从传统的全月统一电价模式转向更加灵活的全月24小时电价模式。本文提出了一种现货市场零售... 详细信息

该文探讨了在电力市场发展中,中长期交易与现货交易如何实现有效衔接以及分时段交易的重要作用。文章通过引入分时电价机制,阐述了如何引导用户从传统的全月统一电价模式转向更加灵活的全月24小时电价模式。本文提出了一种现货市场零售分时用户结算模式,该模式首先根据月度总用电量进行第一次结算,再计算出准确的电费,利用两次结算结果的差异执行补差操作,旨在提升电费结算的准确性与效率。文章提供了一个用于计算零售分时用户电费的数字化系统设计案例,展示了该结算模式的实际应用。应用证明,这种结算模式的创新有利于推动分时交易机制落地,激励用户积极参与负荷调节,并为构建新型电力系统提供了实践案例。

关键词：电力市场电力现货市场分时段交易零售分时用户电费结算

Electrochemical reduction of carbon dioxide to produce formic acid coupled with oxidative conversion of biomass

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Journal of Energy Chemistry 2024年第5期92卷 705-729页

作者： Xi Liu Yifan Wang zhiwei Dai Daihong Gao Xuebing Zhao Key Laboratory of Industrial biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Institute of Applied Chemistry Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Electrochemical reduction of CO_(2)(CO_(2)RR)has become a research hot spot in recent years in the context of carbon *** is one of the most promising products obtained by electrochemical reduction of CO_(2) due to its high energy value as estimated by market price per energy unit and wide application in chemical *** is the most abundant renewable resource in the natural *** biomass oxidative conversion with CO_(2)RR driven by renewable electricity would well achieve carbon *** this work,we comprehensively reviewed the current research progress on CO_(2)RR to produce HCOOH and coupled system for conversion of biomass and its derivatives to produce value-added ***-and bi-based electrocatalysts are discussed for CO_(2)RR with regards to the structure of the catalyst and reaction ***-oxidation reactions of biomass derived sugars,alcohols,furan aldehydes and even polymeric components of lignocellulose were reviewed as alternatives to replace oxygen evolution reaction(OER)in the conventional electrolysis *** was recommended that to further improve the efficiency of the coupled system,future work should be focused on the development of more efficient and stable catalysts,careful design of the electrolytic cells for improving the mass transfer and development of environment-friendly processes for recovering the formed formate and biomass oxidation products.

关键词： Electrochemical reduction of CO_(2) Formic acid Oxidative conversion of biomass Lignocellulose Coupled system

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水轮机导叶漏水量测试研究综述

湖南电力 2020年第5期40卷 6-9页

作者：毕智伟国网湖南省电力有限公司电力科学研究院湖南长沙410007

水轮机导叶漏水量测试是评判机组制造、安装、检修质量的重要指标,从水轮机导叶漏水量的测试方法选择、计算方法、闸门漏水量影响等方面进行了总结。结果表明:使用容积法时,采用切线斜率比拟合系数法的测试结果更为精确;闸门漏水量对导... 详细信息

水轮机导叶漏水量测试是评判机组制造、安装、检修质量的重要指标,从水轮机导叶漏水量的测试方法选择、计算方法、闸门漏水量影响等方面进行了总结。结果表明:使用容积法时,采用切线斜率比拟合系数法的测试结果更为精确;闸门漏水量对导叶漏水量测试结果存在一定影响,在进水口闸门漏水量合格的情况下,名义闸门漏水量对导叶漏水量计算结果的影响相对较小。建议根据实际情况和测试条件、测试精度需求决定导叶漏水量的测试方法。

关键词：导叶漏水量闸门漏水量容积法声学法拟合系数法切线斜率法

Quaternary Sporopollen Records and Environmental Evolution in the Dalangtan of Qaidam Basin

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 440-440页

作者： YANG Zhenjing YANG Qinghua ZHEN Mianping HOU Xianhua bi zhiwei LIU Linjing Institute of Hydrogeology and environmental Chinese Academy of Geological Sciences Institute of mineral Resources Chinese Academy of Geological Sciences Faculty of Earth Sciences China University of Geosciences

Since the Quaternary,very thick lacustrine sediments have been deposited in Dalangtan of Qaidam *** on a study of high-resolution sporopollen analysis on the Dalangtan ZK06 drilling,and paleomagnetic dating

关键词： Sporopollen assemblage Climatic cycles Uplift of Tibetan Plateau Dalangtan Qaidam Basin