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Preparation and Properties of Glass with High Transmittance and Intense Gamma Ray Shielding

硅酸盐学报 2024年第10期52卷 3301-3310页

作者： ZHANG Meilun CAO Zhenbo YANG Shengyun ZHANG Yang HAN Yu QIU Fu ZHOU You ZHENG Jingming LIU Hui jia jinsheng China National Building Material Photonics Technology Co. Ltd.Zaozhuang 277000ShandongChina China Building Materials Academy Co. Ltd.Beijing 100000China

Introduction As a kind of high-energy electromagnetic radiation,gamma rays can lead to radiation effect and environmental *** ensure the reliability and safety utilization of gamma radiations in different areas,materials with reliable gamma shielding performances should be *** existing efforts are to use glasses as alternative for the conventional radiation shielding *** a typical window material,glass itself has attracted wide attention due to its unique chemical and physical *** them,lead-based radiation shielding materials are widely used in the field of ionizing radiation protection due to their reliable physical *** the nuclear industry and high energy physics laboratories,different materials can be used for temporary or permanent *** lead-based glass doped with heavy metal oxide PbO is widely used in the field of radiation shielding for a long time with reliable light transmission properties,which facilitates the observation and monitoring of radiation *** this paper,three kinds of transparent silicate glass with different PbO contents were prepared by a high-temperature melting forming *** gamma-rays protection abilities of the three kinds of glass were investigated through experimental and thermotical *** chemical and thermal stability of the glass were also *** addition,the influence mechanism of the structure and performance differences of the three kinds of glass was also *** Analytical pure quartz sand(SiO_(2),purity 99.5%,in mass,the same below),lead monoxide(PbO,purity 99.0%),potassium nitrate(KNO3,purity 99.0%)and sodium nitrate(NaNO3,purity 99.0%)were selected as raw materials for preparation of three kinds of gamma-rays shielding glass materials by a high-temperature melting *** appropriate amount of raw materials was thoroughly mixed and added to 3 L quartz crucible and heated in air at 1200℃.Then the raw materials were melted at 1250℃for 14

关键词： transmittance gamma rays radiation shielding glass

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平顶山矿区多煤层卸压立体抽采模式与工程示范

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煤炭科学技术 2024年第9期52卷 162-172页

作者：李延河倪小明贾晋生平顶山天安煤业股份有限公司河南平顶山467000 中国平煤神马控股集团有限公司河南平顶山467000 河南理工大学能源科学与工程学院河南焦作454000 河南超蓝能源科技有限公司河南平顶山467000

平顶山矿区多煤层发育、含气层段多,仅靠井下进行瓦斯治理工程量大、难度高。为了开辟平顶山矿区瓦斯抽采新模式,达到“采一层抽多层”的目的,采用气测录井与含气量测试相结合的方法精准判识了煤系主要含气层段和含气量;采用体积法评价... 详细信息

平顶山矿区多煤层发育、含气层段多,仅靠井下进行瓦斯治理工程量大、难度高。为了开辟平顶山矿区瓦斯抽采新模式,达到“采一层抽多层”的目的,采用气测录井与含气量测试相结合的方法精准判识了煤系主要含气层段和含气量;采用体积法评价了东部5对矿井采动区和采空区的煤系气资源量。基于“O”形圈理论和“防-抗-让”思想,分别优化设计了采动井、采空井的井位、层位和井身结构,构建了采动区、采空区多煤层卸压立体抽采模式并进行了工程示范。结果表明:(1)二_(1)煤层顶板200 m范围内存在四煤组、三煤组、二_(1)煤层顶板60 m范围内的砂岩/泥质砂岩互层段等3处主要含气段。平顶山矿区东部5对矿井的采动区和采空区资源量分别为26.36×10~8 m^(3)和20.00×10~8 m^(3)。(2)采动井最佳井位为0.17~0.28倍采长,且靠近回风巷条带区域;走向上,采动井的间距一般为80~100 m。创建了“大口径、避开岩体变形强烈区、P110梯型扣套管”的采动直井稳孔技术体系和“下行水平轨迹+提高套管强度”的采动L型水平井稳产技术体系,保证了产气通道的畅通性。采空井一般布置在距离回风巷30~50 m的区域,完钻位置一般为二_(1)煤层顶板40~60 m的范围;筛管布置在四煤段顶板至裂隙带底部。(3)建立了“地面采动直井/定向井-采动L型水平井-采空井”联作的卸压立体抽采模式,实现了多气源立体抽采。截至2024年4月30日,累计抽采纯量达5258.8万m^(3),总利用量达到3735.4万m^(3),率先在河南省实现了煤系气产业化开发,示范和引领带动作用显著。

关键词：煤系气多煤层卸压立体抽采模式采动区采空区平顶山矿区

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耐辐射高铅玻璃熔制挥发物分析及控制

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硅酸盐学报 2024年第7期52卷 2364-2370页

作者：杨胜赟曹振博张梅伦张洋王可韩玉吕海风周游贾金升中建材光子科技有限公司山东枣庄277000 中国建筑材料科学研究总院有限公司北京100000

用于制备耐辐射光纤面板的高铅(铅当量≥0.3)玻璃材料须具备较高的折射率、较好的X射线吸收性能、较高的可见光透过率以及良好的热稳定性和化学稳定性。但由于其高铅含量对熔制坩埚及耐火材料腐蚀性极高,且熔制过程中挥发量较高,玻璃组... 详细信息

用于制备耐辐射光纤面板的高铅(铅当量≥0.3)玻璃材料须具备较高的折射率、较好的X射线吸收性能、较高的可见光透过率以及良好的热稳定性和化学稳定性。但由于其高铅含量对熔制坩埚及耐火材料腐蚀性极高,且熔制过程中挥发量较高,玻璃组分不易稳定控制,目前仅国外少数企业能够高质量稳定生产。研究了玻璃熔制过程中影响挥发物的3个主要因素,有效控制挥发物的挥发率由2.00%降至0.51%左右,确定了最佳熔制温度以及通气压强,并在此条件下分别采用2种方式向玻璃中引入铅,通过能谱仪和光电子能谱仪对该高铅玻璃在熔制过程中的挥发物进行了研究,确定了其挥发物成分以铅氧化物为主,其中铅的价态以四价为主,二价为辅。

关键词：耐辐射光纤面板玻璃熔制挥发物

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Several issues to be considered for long-term better behavior of concrete gravity dams

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Frontiers of Structural and Civil Engineering 2010年第1期4卷 40-46页

作者： jinsheng jia China Institute of Water Resources and Hydropower Research Beijing 100038China

Along with economic,social quick development and urbanization,dams and reservoirs are of strategic importance for flood control,water supply,electricity production,irrigation,etc.,both for developed countries and for developing *** change is a new challenging issue to be considered which will speed up the development of hydropower in developing *** and more attention will be paid on the long-term better behavior of dams to guarantee the safety of the people involved and the better development of the *** are about 50000 old dams in the world and a lot of them have been completed and operated for more than 50 ***,how do we evaluate the dams’safety?How do we make the decision to do rehabilitation work or to rebuild a new dam based on evaluation results?The life span and the real safety status of old dams becomes a challenging task for the dam society,especially for China because it has more than 6000 dams to be evaluated and rehabilitated within the next few *** on the investigation of the Fengman gravity dam,which is 91.7 m high,operated since 1943 and suffered uplift pressure,freeze and thaw problems,etc.,discussions on the life span evaluation of old concrete gravity dams have been *** reasonable coefficient of dam safety has been *** social decision for the final choice after comprehensive studies has been introduced.

关键词： dam safety economic life span structural life span environmental life span rehabilitation social decision

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The Cemented Material Dam： A New, Environmentally Friendly Type of Dam

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Engineering 2016年第4期2卷 490-497页

作者： jinsheng jia Michel Lino Feng Jin Cuiying Zheng China Institute of Water Resources and Hydropower Research Beijing 100038 China ISL Ingeierie Saint-Jean-de-Luz 64500 France Tsinghua University Beijing 100084 China

The first author proposed the concept of the cemented material dam （CMD） in 2009. This concept was aimed at building an environmentally friendly dam in a safer and more economical way for both the dam and the area downstream. The concept covers the cemented sand, gravel, and rock dam （CSGRD）, the rockfill concrete （RFC） dam （or the cemented rockfill dam, CRD）, and the cemented soil dam （CSD）. This paper summarizes the concept and principles of the CMD based on studies and practices in projects around the world. It also introduces new developments in the CSGRD, CRD, and CSD.

关键词： Cemented material dam Cemented sand, gravel, and rock dam Rockfill concrete dam Cemented rockfill dam Cemented soil dam Material properties

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Spectral Representation and Analysis of the KBR Precision Based on the Earth Gravity Spectrum

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Geo-Spatial Information Science 2005年第3期8卷 205-208,219页

作者： LUO jia NING jinsheng LUO Zhicai School of Geodesy and Geomatics Wuhan University Wuhan China

Satellite-to-Satellite Tracking in low-low model （SST-Ⅱ） is a new technique to resolve the series of problems met in the determination of the earth＇s gravity field. As the key technique of SST-Ⅱ, KBR can get SST-Ⅱ measurements directly. So the KBR performance analysis is the first step in SST-Ⅱ design. In this paper, assuming that the satellite pairs of SST-Ⅱ are in near circle polar orbits, the spectrum relationship between the earth gravity field and KBR is established using analytic method. And then some examples are analyzed, the suggestions and conclusions are drawn from these examples. The research results could be taken as a reference for future satellite gravity project of China.

关键词： SST-Ⅱ KBR earth gravity field spectrum

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基于知识图谱联合ERNIE-DPCNN模型的药品不良反应自动关联性评价方法研究

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中国药物警戒 2024年第2期21卷 163-166,180页

作者：贾晋生刘红亮王青侯永芳李馨龄国家药品监督管理局药品评价中心国家药品监督管理局药物警戒研究与评价重点实验室北京100076 清华大学药物警戒信息技术与数据科学创新中心北京100084

目的针对当前药品不良反应关联性评价存在的效率较低和主观性评估问题,通过建立药品不良反应关联性评价模型,探索药品不良反应自动关联性评价方法。方法利用文献及互联网来源,对获取的不良反应报告标注数据(7 301条)进行知识抽取,构... 详细信息

目的针对当前药品不良反应关联性评价存在的效率较低和主观性评估问题,通过建立药品不良反应关联性评价模型,探索药品不良反应自动关联性评价方法。方法利用文献及互联网来源,对获取的不良反应报告标注数据(7 301条)进行知识抽取,构建药品不良反应知识图谱,建立知识驱动的ERNIE-DPCNN自动关联性评价模型。结果提出的知识图谱联合ERNIE-DPCNN模型在测试集中的精确度、召回率和F1值分别达到82.18%、81.40%、81.21%,相对于其他基线模型各项评估指标均取得了最高值。结论知识图谱联合ERNIE-DPCNN模型的方法能提高药品不良反应关联性评价效率,具备较强的准确性,并在一定程度上减少主观性评估误差,对基于人工智能的自动化评价有一定参考价值。

关键词：药品不良反应 ERNIE-DPCNN模型知识图谱关联性评价文本分类深度学习人工智能

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GNSS拟合高程代替水准测量的可行性分析:以黄河上游水电基地区域为例

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水利水电技术（中英文） 2024年第S1期55卷 340-345页

作者：杨会臣贾金生郑璀莹武志刚赵志华何欣赵春中国水利水电科学研究院北京10038 国家电投集团青海黄河电力技术有限责任公司青海西宁810003

GNSS拟合高程代替水准测量有重要的现实意义,有必要对其进行可行性分析。黄河上游水电基地是中国在黄河上游地区开发的重要水利工程群,其安全监测具有至关重要的作用。因此,本文基于黄河上游水电基地GNSS自动监测网开展实验,从GNSS高程... 详细信息

GNSS拟合高程代替水准测量有重要的现实意义,有必要对其进行可行性分析。黄河上游水电基地是中国在黄河上游地区开发的重要水利工程群,其安全监测具有至关重要的作用。因此,本文基于黄河上游水电基地GNSS自动监测网开展实验,从GNSS高程拟合方法、GNSS数据处理策略和GNSS高程方向定位结果等方面详细论证。结果表明,GNSS拟合高程具有替代三等水准的可行性。

关键词： GNSS 水准测量变形监测

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Review of drought impacts on carbon cycling in grassland ecosystems

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Frontiers of Earth Science 2020年第2期14卷 462-478页

作者： Tianjie LEI Jie FENG Cuiying ZHENG Shuguang LI Yang WANG Zhitao WU Jingxuan LU Guangyuan KAN Changliang SHAO jinsheng jia Hui CHENG State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Beijing 100038China China Institute of Water Resources and Hydropower Research(IWHR) Beijing 100038China Institute of Loess Plateau Shanxi UniversityTaiyuan 030006China National Hulunber Grassland Ecosystem Observation and Research Station&Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China Department of Geography/CGCEO Michigan State UniversityEast LansingMI 48823USA State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China

Grasslands play a key role in both carbon and water *** semi-arid and arid grassland areas,the frequency and intensity of droughts are ***,the influence of a drought on grassland carbon cycling is still *** this paper,the relationship between drought and grassland carbon cycling is described from the perspective of drought intensity,frequency,duration,and *** on a large amount of literature,we determined that drought is one of the most prominent threats to grassland carbon cycling,although the impacts of different drought conditions are *** effects of a drought on grassland carbon cycling are more or less altered by drought-induced disturbances,whether individually or in ***,a new conceptual model is proposed to better explain the mechanism of droughts on grassland carbon *** present,evaluations of the effects of droughts on grassland carbon cycling are mainly qualitative.A data fusion model is indispensable for evaluating the fate of carbon cycling in a sustainable grassland system facing global *** the future,multi-source data and models,based on the development of single and multiple disturbance experiments at the ecosystem level,can be utilized to systematically evaluate drought impacts on grassland carbon cycling at different ***,more advanced models should be developed to address extreme drought events and their consequences on energy,water,and carbon cycling.

关键词： drought carbon cycling grasslands conceptual model interactive mechanisms data fusion

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A Degree Condition on Long Paths and Large Cycles

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Systems Science and Systems Engineering 1993年第1期3卷 93-95页

作者： jia Zhensheng LU jinsheng Department of Mathematics and Mechanics, Tai yuan University of Technology

We present a new condition ensuring the existence of a large cycle of passing through given edge. Let l(C) denote the length of the cycle C. Suppose G is a 4-connected graph with vertices set {x1,X2, ···,Xn} and edge set E and with the property that, for any two positive integers j and k,d(xj)n-1,then d(xj)+d(xk)>m;(2)if j+kmin(k+3,m).In this paper, we proved that for any given edge e 6 E, there exists a cycle which passes through e abd with the length > min(m - 1, n).

关键词： path cycle graph

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