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Nuclear Science and Techniques 2009年第5期20卷 292-296页

作者： MA pan dai Jianrong CUI Weijie Department of Radiation Oncology/Cancer Institute Chinese Academy of Medical Sciences Beijing 100021 China

In this paper, we describe a quantitative evaluation of the dosimetry effect of lack of side-scatter volume (LSSV). MapCheck, an integration diode array, was used to measure dose maps for three large non-IMRT fields (30cm ×30 cm and 40 cm×40 cm open fields, and 30 cm×30 cm wedge field with wedge angle of 60°) and 19 large IMRT fields. For each field, measurement was performed twice, under the conditions of (1) full scatter volume and (2) LSSV. Condition 1 was satisfied by adding PMMA slabs against the side of the MapCheck, and Condition 2, without PMMA slabs. The measured dose maps were compared with pass rate and their difference was scored when the acceptance criterion was set to 0.5%, 1%, 2%, 3%, etc. For very large open fields, the effect of LSSV may be clinically significant, while for large wedge fields and IMRT fields, the effect is negligible.

关键词：放射量测定 LSSV 核技术

Zircon U-Pb Geochronology of Baoyintu Group in the Northwestern Margin of the North China Craton and Its Geological Significance

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Journal of Earth Science 2023年第5期34卷 1511-1526页

作者： Chengwu Ding Yifei Liu pan dai Sihong Jiang Chengzhen Ding School of Resources and Environmental Engineering Shandong University of TechnologyZibo 255000China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Geophysical Research Institute of BGP Inc.China National Petroleum Corporation Zhuozhou 072751China

The Baoyintu uplift is located at the northwestern margin of the North China Craton(NCC). The affiliation and evolution history of the uplift have been unresolved until now. Here we present LA-ICP-MS and SHRIMP U-Pb data for zircons extracted from samples of monzogranitic orthogneiss and the Baoyintu Group in the uplift. The 1 679 ± 13 Ma date for the orthogneiss demonstrates that Late Palaeoproterozoic rocks do exist in the uplift. The ca. 1 413 Ma minimum age of detrital zircons in metasedimentary rocks shows that the maximum age of the Baoyintu Group is Mesoproterozoic. The age distribution of detrital zircons in the first unit of the Group form clusters at ca. 2 680, 2 450, 1 800 and 1 560 Ma, which partly correspond to tectonic-magmatic-metamorphic events previously recognised in the NCC, and show that the metasedimentary rocks are largely sourced from different parts of the NCC. These confirm that the Baoyintu uplift is part of the NCC. Amphibolite with a dolerite protolith from the third unit of Baoyintu Group shows evidence for metamorphism during ca. 877–851 Ma. This combined with published geochronological data indicate the presence of Neoproterozoic magmatic and metamorphic events in the NCC, which significantly increases our understanding of the Proterozoic tectonic evolution of the region and its possible correlation with the Rodinian Supercontinent.

关键词： Proterozoic Baoyintu Group zircon U-Pb dating North China Craton geochemistry

High temperature tensile properties,fracture behaviors and nanoscale precipitate variation of an Al-Zn-Mg-Cu alloy

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Progress in Natural Science:Materials International 2020年第1期30卷 63-73页

作者： pan dai Xian Luo Yanqing Yang Zongde Kou Bin Huang Jinxin Zang Jigang Ru State Key Laboratory of Solidification Processing Northwestern Polytechnical University Beijing Institute of Aeronautical Materials

In order to assess Al-Zn-Mg-Cu alloys as potential high temperature structural materials,the hardness,tensile properties and fracture behaviors of 7085 Al alloy were investigated at various temperatures from room temperature to 175℃.High-resolution transmission electron microscopy was used to investigate the evolutions of precipitates at different temperatures,particularly on the relationship between microstructural evolution and tensile *** results reveal that both the microstructure and mechanical properties of the alloy are quite sensitive to the environmental *** the temperature increases,the hardness and strength decrease while the elongation and reduction of area *** tensile testing temperature rises,the strain hardening exponent(n) decreases due to the thermal softening *** fracture mode of the alloy transforms from mixture of intergranular and transgranular fracture to completely transgranular dimples when tensile testing temperature reaches 150℃.The precipitate sequence during high temperature tests is coincident with that of *** the increase of tensile testing temperature,the mean precipitate radius grows larger,and the distribution of grain boundary precipitates transforms from continuous to discontinuous.

关键词： 7085 Al alloy Microstructure evolution Tensile strength Fracture mode

Research on Volt/Var Control of Distribution Networks Based on PPO Algorithm

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Computer Modeling in Engineering & Sciences 2023年第1期134卷 599-609页

作者： Chao Zhu Lei Wang dai pan Zifei Wang Tao Wang Licheng Wang Chengjin Ye State Grid Zhejiang Economic and Technological Research Institute Hangzhou310008China College of Information Engineering Zhejiang University of TechnologyHangzhou310023China College of Electrical Engineering Zhejiang UniversityHangzhou310058China

In this paper,a model free volt/var control(VVC)algorithm is developed by using deep reinforcement learning(DRL).We transform the VVC problem of distribution networks into the network framework of PPO algorithm,in order to avoid directly solving a large-scale nonlinear optimization *** select photovoltaic inverters as agents to adjust system voltage in a distribution network,taking the reactive power output of inverters as action *** appropriate reward function is designed to guide the interaction between photovoltaic inverters and the distribution network *** is used to output system node voltage and network *** method realizes the goal of optimal VVC in distribution *** IEEE 13-bus three phase unbalanced distribution system is used to verify the effectiveness of the proposed *** results demonstrate that the proposed method has excellent performance in voltage and reactive power regulation of a distribution network.

关键词： Deep reinforcement learning voltage regulation unbalance distribution systems high photovoltaic permeability photovoltaic inverter volt/var control

掺杂及卤化调控富勒烯氧化还原电位的DFT研究

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原子与分子物理学报 2025年第4期42卷 65-72页

作者：李健孙冰花王春妮李奥吕祥鸿王晨代盼白真权西安石油大学新能源学院西安710000 西安石油大学材料科学与工程学院西安710000 中国石油集团工程材料研究院有限公司西安710000

采用基于密度泛函理论(DFT)的模拟计算方法,分别计算了原始富勒烯C_(60)和11种单原子置换(掺杂及卤化)富勒烯材料C_(59)X(X=B、Si、N、P、As、O、S、Se、F、Cl、Br)的氧化还原电位、电子亲合能、分子轨道能级.其中,B、As、P、Si、N、Se... 详细信息

采用基于密度泛函理论(DFT)的模拟计算方法,分别计算了原始富勒烯C_(60)和11种单原子置换(掺杂及卤化)富勒烯材料C_(59)X(X=B、Si、N、P、As、O、S、Se、F、Cl、Br)的氧化还原电位、电子亲合能、分子轨道能级.其中,B、As、P、Si、N、Se、S单原子置换导致氧化还原电位正移,B置换后增幅最高(3.655 V);F、Cl、Br、O单原子置换后,氧化还原电位均负移,F置换后降幅最大(2.476 V).在所考察的12种富勒烯分子中,C_(59)B和C_(59)F的电子亲和能(EA)分别为最小值(-3.901 eV)和最高值(-2.577 eV),二者分别具有最强和最弱的得电子倾向.在C_(59)B和C_(59)F中,B、F置换原子周围存在电荷偏聚,且B、F与周围C原子的成键主要来自于-2.5 eV和-7.5 eV能级附近2p电子的相互作用.

关键词：密度泛函理论富勒烯C_(60) 氧化还原电位电子结构

Geochemistry and Sr-Nd-Pb Isotopes of the Granites from the Hashitu Mo Deposit of Inner Mongolia, China： Constraints on Their Origin and Tectonic Setting

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 106-120页

作者： DING Chengwu dai pan BAGAS Leon NIE Fengjun JIANG Sihong WEI Junhao DING Chengzhen ZUO Pengfei ZHANG Ke MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Faculty of Earth Resources China University of Geosciences(Wuhan)Wuhan 430074HubeiChina School of Earth and Environment The University of Western Australia35 Stirling HighwayCrawleyWestern Australia 6009 Geophysical Research Institute of BGP Inc.China National Petroleum Corporation Zhuozhou 072751 HebeiChina School of the Earth Sciences and Resources China University of GeosciencesBeijing 100083China

The Hashitu molybdenum deposit is located in the southern part of the Great Hinggan Range, NE China. Molybdenum mineralization is hosted by and genetically associated with monzogranite and porphyritic syenogranite. Sr-Nd-Pb isotopes of the intrusions show that the porphyritic syenogranite has initial ^87Sr/^86Sr ratios of 0.70418-0.70952, ENd（t） values of 1.3 to 2.1 （t=143 Ma）, ^206Pb/^204Pb ratios of 19.191-19.573, ^207Tpb/^204pb ratios of 15.551-15.572, and ^208Pb/^204Pb ratios of 38.826-39.143. The monzogranite has initial 87Sr/86Sr ratios of 0.70293-0.71305, εNd（t） values of 1.1 to 2.0 （t=-147 Ma）, ^206Pb/^204pb ratios of 19.507-20.075, ^207Pb/^204Pb ratios of 15.564-15.596, and ^208Pb/^204Pb ratios of 39.012-39.599. The calculated Nd model ages （TDM） for monzogranite and porphyritic syenogranite range from 866 to 1121 Ma and 795 to 1020 Ma, respectively. The granitic rocks in the Hashitu area have the same isotope range as granites in the southern parts of the Great Hinggan Range. The isotope composition indicates that these granites are derived from the partial melting of a juvenile lower crust originating from a depleted mantle with minor contamination by ancient continental crust. The integrating our results with published data and the Late Mesozoic regional tectonic setting of the region suggest that the granites in the Hashitu area formed in an intra-continent extensional setting, and they are related to the thinning of the thickened lithosphere and upwelling of the asthenosphere.

关键词： granite Sr-Nd-Pb isotopes Hashitu Mo deposit Great Hinggan Range

1-MeV electron irradiation effects on InGaAsP/InGaAs double-junction solar cell and its component subcells

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Science China(Information Sciences) 2017年第12期60卷 117-119页

作者： Xiaofan ZHAO Maliya HEINI Momin SAILAI Abuduwayiti AIERKEN Qi GUO Yudong LI Shulong LU pan dai Yuanyuan WU Ming TAN Key Laboratory of Functional Materials and Device for Special Environments Xinjiang Technical Institute of Physics & Chemistry Chinese Academy of Sciences Xinjiang Key Laboratory of Electronic Information Material and Device University of Chinese Academy of Sciences Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics

Solar cells(SCs)are used as the primary source of power in satellites and other space missions,and operate in a harsh radiation environment in *** demand for power has been increasing in various space *** applications require high radiation hardness and power-to-mass ratio for *** the past decade,high efficiency(30%at AM0,1 sun),lattice-matched,Ga In P/Ga As/Ge

关键词： MeV electron irradiation effects on InGaAsP/InGaAs double-junction solar cell and its component subcells As Ga

Effect of austempering parameters on microstructure and mechanical properties of horizontal continuous casting ductile iron dense bars

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China Foundry 2015年第2期12卷 104-110页

作者： Chun-jie Xu pan dai Zheng-yang Zhang Zhong-ming Zhang Jin-cheng Wang Yong-hui Liu School of Materials Science and Engineering Xi'an University of Technology State Key Laboratory of Solidification Processing Northwestern Polytechnical University Shaanxi Hua An Continuous Casting Co. Ltd.

In the present research, the orthogonal experiment was carried out to investigate the influence of different austempering process parameters （i.e. austenitizing temperature and time, and austempering temperature and time） on microstructure and mechanical properties of LZQT500-7 ductile iron dense bars with 172 mm in diameter which were produced by horizontal continuous casting （HCC）. The results show that the major factors influencing the hardness of austempered ductile iron （ADI） are austenitizing temperature and austempering temperature. The fraction of retained austenite increases as the austenitizing and austempering temperatures increase. When austenitizing temperature is low, acicular ferrite and retained austenite can be efifciently obtained by appropriately extending the austenitizing time. The proper austmepering time could ensure enough stability of retained austenite and prevent high carbon austenite decomposition. The optimal mechanical properties of ADI can be achieved with the fol owing process parameters： austenitizing temperature and time are 866 ＆#176;C and 135 min, and austempering temperature and time are 279 ＆#176;C and 135 min, respectively. The microstructure of ADI under the optimal austempering process consists of ifne acicular ferrite and a smal amount of retained austenite, and the hardness, tensile strength, yield strength, elongation and impact toughness of the bars are HBW 476, 1670 MPa, 1428 MPa, 2.93%and 25.7 J, respectively.

关键词： horizontal continuous casting (HCC) ductile iron dense bars austempered ductile iron (ADI) microstructure and mechanical properties orthogonal test

Optical properties of Zn-diffused InP layers for the planar-type InGaAs/InP photodetectors

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Journal of Semiconductors 2017年第12期38卷 56-61页

作者： Guifeng Chen Mengxue Wang Wenxian Yang Ming Tan Yuanyuan Wu pan dai Yuyang Huang Shulong Lu Key Laboratory for New Type of Functional Materials in Hebei Province School of Material and EngineeringHebei University of TechnologyTianjin 300130China Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of Sci-encesSuzhou 215123China Suna optoelectronics Suzhou 215123China

Zn diffusion into InP was carried out ex-situ using a new Zn diffusion technique with zinc phosphorus particles placed around InP materials as zinc source in a semi-closed chamber formed by a modified diffusion furnace. The optical characteristics of the Zn-diffused InP layer for the planar-type InGaAs/InP PIN photodetectors grown by molecular beam epitaxy （MBE） has been investigated by photoluminescence （PL） measurements. The temperature-dependent PL spectrum of Zn-diffused InP samples at different diffusion temperatures showed that band-to-acceptor transition dominates the PL emission, which indicates that Zn was commendably diffused into InP layer as the acceptor. High quality Zn-diffused InP layer with typically smooth surface was obtained at 580 ℃for 10 min. Furthermore, more interstitial Zn atoms were activated to act as acceptors after a rapid annealing process. Based on the above Zn-diffusion technique, a 50μm planar-type InGaAs/InP PIN photodector device was fabricated and exhibited a low dark current of 7.73 pA under a reverse bias potential of -5 V and a high break- down voltage of larger than 41 V （1 〈 10μA）. In addition, a high responsivity of 0.81 A/W at 1.31/~m and 0.97 A/W at 1.55μm was obtained in the developed PIN photodetector.

关键词： Zn diffusion semi-closed InGaAs/InP PIN photodetectors photoluminescence (PL) dark current responsivity

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高速铁路接触网行波传播特性研究

铁道学报 2014年第2期36卷 25-30页

作者：戴攀刘田周浩国网浙江省电力公司经济技术研究院浙江杭州310008 国网浙江桐庐县供电公司浙江杭州311500 浙江大学电气工程学院浙江杭州310027

基于高速铁路接触网线路参数推导相模变换矩阵,并对接触网线路进行电磁解耦,计算得到行波各模量的衰减系数和相位速度。通过对衰减系数和相位速度频率特性研究发现,不同的频率分量和传输路径会造成不同的衰减和传播速度,因此,行波会在... 详细信息

基于高速铁路接触网线路参数推导相模变换矩阵,并对接触网线路进行电磁解耦,计算得到行波各模量的衰减系数和相位速度。通过对衰减系数和相位速度频率特性研究发现,不同的频率分量和传输路径会造成不同的衰减和传播速度,因此,行波会在传播过程中出现色散现象,这给故障行波的准确提取带来困难。大地电阻率的变化对线模分量的衰减系数和相位速度影响不大,地模分量的衰减系数和相位速度随大地电阻率的增大而减小。在电磁暂态程序(EMTP)中建立基于频率相关参数的***线路模型。仿真结果表明故障行波的模2分量在故障点奇异性明显,适用于各种短路故障的行波故障测距。

关键词：行波相模变换传播特性接触网高速铁路