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Microstructural Transitions during the Rapid Cooling Process of liquid Metal Al

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Journal of Materials Science & Technology 1998年第5期14卷 461-464页

作者： li, jiyong liu, Rangsu Xie, Quan Peng, Ping Zhou, Zheng Hunan Univ Dept Chem Changsha 410012 Peoples R China Hunan Univ Dept Phys Changsha 410012 Peoples R China

From a molecular-dynamics simulation study, it was demonstrated that the microscopic structure transitions is mainly determined by the changes of various microstructural configurations. There are two obvious phase transition points during the rapid cooling process. The first transition point is consistent with the well-known glass transition. The second one is a new weaker transition at low temperature. The cluster having 7-fold symmetry still exist in the supercooled liquid metal Al, though it occupies only 0.1% of the total number of clusters in the system and disappears below 550 K, namely, it can not exist in the glassy state. These results will give us a new way to understand the structural transition at microscopic level. (Edited author abstract) 15 Refs.

关键词： Aluminum

ERGODIC CAPACITY FORMULA OF MIMO-OFDM SYSTEMS UNDER CORRELATED FREQUENCY SELECTIVE RAYLEIGH FADING CHANNELS

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Journal of Electronics(China) 2007年第5期24卷 588-592页

作者： Pang jiyong li Jiandong Zhao linjing Broadband Wireless Communications Lab Information Science InstituteState Key Lab of Integrated Service Networks Xidian University Xi＇an 710071 China

An explicit formula for the ergodic capacity of Orthogonal Frequency Division Multiplexing (OFDM)-based Multiple-Input Multiple-Output (MIMO) systems under correlated frequency selective Rayleigh channels is derived,by simplifying the channel response matrix in frequency domain into the so-called Kronecker model composed of three kinds of correlations,*** tap gain correlation and spatial fading correlations at both transmitter and *** derived formula is very simple and convenient for one to estimate the effects of all three kinds of correlations on MIMO-OFDM *** taps are independent,there is a very simple expression for the ergodic *** case of tap correlation,the capacity formula could be further given in an integral *** validity of the new formula is verified and the effects of correlations,delay spread as well as the number of subcarriers on the ergodic capacity are evaluated via Monte Carlo simulations.

关键词： Multiple-Input Multiple-Output (MIMO) Orthogonal Frequency Division Multiplexing(OFDM) Kronecker product Channel correlation Ergodic capacity

Reservoir Characteristics of Fine-grained Sedimentary Rocks in Saline Lakes in the Cenozoic Upper Ganchaigou Formation,Southwestern Qaidam Basin,NW China

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Acta Geologica Sinica(English Edition) 2022年第3期96卷 1070-1081页

作者： SHENG Jun liU Jincheng li Yunlong ZOU Haiyan LONG Anlin WANG lin li jiyong QI Qingshan YANG Xiaojing li Yanan Exploration&Development Research Institute of PetroChina Qinghai Oilfield Company DunhuangGansu 736200China No.2 Oil Production Plant of PetroChina Qinghai Oilfield Company DunhuangGansu 736200China No.1 Oil Production Plant of PetroChina Qinghai Oilfield Company DunhuangGansu 736200China

Cenozoic fine-grained sedimentary rocks in the southwestern Qaidam Basin,as typical salinized lacustrine sediments,are significantly different from those in other freshwater lakes under the impact of the high salinity in the *** fine-grained sedimentary rock samples were selected from the lower member of Neogene(N_(1))in the Gaskule Oilfield,Qaidam Basin,northwest China,with the aim to analyze and test their petrology,pore structure,and organic geochemical characteristics and determine its genesis and geological *** on previous results,a new genesis of mixed sedimentary rocks is *** Cenozoic lacustrine fine-grained sedimentary rocks in SW Qaidam Basin belong to mixed sedimentary rocks,which can be divided into three types,including carbonate and terrigenous clastic-bearing mudstone,carbonate-bearing to terrigenous clastic mixed sedimentary rocks,and carbonate-terrigenous clastic mixed sedimentary *** geneses of mixing are quite different from that of mixed marine *** to the sedimentary characteristics of the salinized lakes,three new geneses of mixed deposits are proposed:syn-sedimentary mixing,varve interbedded mixing,and biogenic *** reservoir spaces of the Cenozoic lacustrine fine-grained sedimentary rocks in SW Qaidam Basin include residual intergranular pores,intercrystalline pores,microfractures,and minor dissolved *** reservoirs have super-low porosity and ultra-low permeability,with a porosity of 1.82%-21.04%,averaging 7.71%,and permeability of(0.0028-254.86)×10^(−3)μm^(2),averaging 2.82×10^(−3)μm^(2).The test results of total organic carbon(TOC)content show that the highest content of organic carbon reached 1.41%,and those of vitrinite reflectance show that Ro ranges from 0.525%-0.824%,with an average of 0.806%.The organic geochemical characteristics show that the fine-grained mixed sedimentary rocks of SW Qaidam Basin have the potential for self-generation and *** an unconventional re

关键词： energy resources unconventional reservoir sedimentary petrology organic geochemistry salinization lacustrine sediments Neogene

Highly sensitive colorimetric detection of NH3 based on Au@Ag@AgCl core-shell nanoparticles

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Chinese Chemical Letters 2021年第9期32卷 2807-2811页

作者： Zhiwei Qiu Yitong Xue jiyong li Yunzhi Zhang Xinyi liang Congying Wen Houjian Gong Jingbin Zeng College of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China College of Science China University of Petroleum(East China)Qingdao 266580China Petroleum Engineering Technology Research Institute Sinopec Shengli Oilfield CompanyDongying 257067China

Abstract:As an important component of the atmosphere,ammonia(NH_(3))plays a very important role in maintaining the balance of ***,it is also one of the most toxic gases that can cause damage to the human respiratory system and mucous membranes even at low *** such,development of highly sensitive and selective NH_(3)sensors is of high significance for environmental monitoring and health ***,we have synthesized Au@Ag@Ag Cl core-shell nanoparticles(NPs)by oxidative etching and precipitating Au@Ag core-shell NPs using FeCl3 and further used them as optical probes for the colorimetric detection of NH_(3).The sensing mechanism is based on the fact that the etching of NH_(3)on AgCl and Ag shell leads to the variations of ingredients and core-to-shell ratio of the Au@Ag@AgCl NPs,thereby inducing noticeable spectral and color *** replacing the outmost layer of Ag with AgCl,not only is the stability of the sensor against oxygen significantly enhanced,but also is the sensitivity of the method *** method exhibits good linear relationship for the detection of NH_(3)from 0 to 5000 mmol/L with the limit of detection of 6.4 mmol/*** method was successfully applied to the detection of simulated air polluted by NH_(3),indicating its practical applicability for environmental *** method shows great potential for on-site NH_(3)detection particularly in remote area,where a simple,fast,low-cost,and easy-to-handle method is highly desirable.

关键词： NH3 detection Au@Ag@AgCl nanoparticles Localized surface plasmon resonance Etching Colorimetric sensor

Paleozoic Multi-Stage Magmatic Events Related to Proto-Tethys and Paleo-Tethys Evolution:Insights from Intrusive Rocks in the Eastern Altyn Orogen,NW China

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Journal of Earth Science 2024年第4期35卷 1130-1148页

作者： jiyong li Yanqing Xia Xilong Zhang Haoyuan Jiang Tianzhu Lei Yongchao Wang Yanhong liu Shanpin liu Xiaobao Zhang Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou730000China Key Laboratory of Petroleum Resources Gansu ProvinceLanzhou730000China University of Chinese Academy of Sciences Beijing100049China

Abundant mafic-felsic intrusions distributed in the Altyn Orogen record orogenic histories related to Proto-Tethys and Paleo-Tethys *** U-Pb dating of the intrusive rocks in the eastern Altyn Orogen identifies at least three major tectono-magmatic episodes,yielding ages of∼426,∼376–373 and∼269–254 *** first two emplacement episodes correspond to the post-collisional magmatism in the Altyn ***∼426 Ma granitoids possess adakitic characteristics coupled with enriched isotopes,suggesting that they originated from partial melting of thickened lower continental crust induced by upwelling asthenospheric mantle after slab break-off of the South Altyn Ocean ***,the∼376–373 Ma mafic-intermediate rocks and coeval granitoids represent a large thermal event that involved mantle melting with induced new juvenile lower continental crust melting in a post-collisional extensional ***,the∼254 Ma diabase dykes intruded into the∼269 Ma granitoids,which were related to the widespread Late Paleozoic magmatism resulting from Paleo-Tethys Ocean ***-collisional magmatism in the Altyn Orogen significantly enhances understanding of the tectono-magmatic evolution in the northern Tibetan *** penetrative influence of Paleo-Tethys Ocean subduction was more extensive than previously thought.

关键词： Proto-Tethys Paleo-Tethys Altyn Orogen multi-stage magmatic events magnetic cores

Expression for peroxisome proliferator-activated receptor gamma in pituitary adenomas 38 cases for semi-quantitative immunohistochemical analysis

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Neural Regeneration Research 2008年第7期3卷 756-759页

作者： Xiaojie Lu Kailai Chen Weiyang Ji Qing Wang Bing li Jiang＇an li jiyong Sun Department of Neurosurgery Wuxi Second Hospital Affiliated to Nanjing Medical University Wuxi 214002 Jiangsu Province China

BACKGROUND： It has been reported that peroxisome proliferator-activated receptor γ （PPAR γ ） is highly expressed in lung cancer, colon cancer, and gastric cancer, as well as other tumors.OBJECTIVE： To study expression of PPAR γ in pituitary adenomas and analyze the role of PPAR γ in hormonal typing of pituitary adenomas. DESIGN, TIME AND SETTING： Semi-quantitative immunohistochemistry of pathological specimens. The experiment was conducted at the Department of Neurosurgery, Wuxi Second Hospital Affiliated to Nanjing Medical University between January 2002 and May 2005. MATERIALS： Surgical resection samples of pituitary adenomas from 38 cases （18 male and 20 female） were analyzed. Eight cases were determined to be invasive pituitary adenomas and 30 cases were non-invasive pituitary adenomas. Hormonal classification of the types of pituitary adenomas revealed somatotrophic adenomas in six cases, corticotrophic adenoma in five cases, prolactinomas in 13 cases, multi-hormone secreting adenomas in six cases, and eight cases of adenoma without altered endocrine function. Five autopsy specimens were collected during the same period from patients of matching age that died from unrelated diseases and were included as normal anterior pituitar3, controls. METHODS： Cell counts for positive immunohistochemical signals were recorded from histopathological sections. The percentage of positive cells was reported as a semi-quantitative analysis. MAIN OUTCOME MEASURES： The rate of PPAR γ positive cells in different types of adenoma was based on hormonal levels and invasiveness of pituitary tumor cells. RESULTS： All tumor biopsies were determined to express PPAR γ. The rate of PPAR γ -positive cells ranged between 8%-65% in the pituitary adenomas. According to hormonal type, PPAR γ expression did not vary between the groups. In addition, there was no significant difference in PPAR γ expression between the non-invasive and invasive pituitary adenomas. CONCLUSIONS： Human p

关键词： Peroxisome proliferator-activated receptor γ pituitary adenomas immunohistochemistry

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石油天然气管道成膜型缓蚀剂研究进展

油田化学 2019年第3期36卷 551-557页

作者：李继勇胜利油田分公司石油工程技术研究院

管道在石油和天然气的生产和运输中起着重要的作用。选用成膜型缓蚀剂是控制油气管道内部腐蚀最经济、最可靠的方法之一。介绍了不同类型腐蚀的机理、特点,通过管道设备材料的选择、pH值稳定剂和缓蚀剂控制管道内部腐蚀情况,分析了油气... 详细信息

管道在石油和天然气的生产和运输中起着重要的作用。选用成膜型缓蚀剂是控制油气管道内部腐蚀最经济、最可靠的方法之一。介绍了不同类型腐蚀的机理、特点,通过管道设备材料的选择、pH值稳定剂和缓蚀剂控制管道内部腐蚀情况,分析了油气管线有机成膜型缓蚀剂(咪唑啉、脂肪胺、乙氧基化胺、季铵化合物、含硫化合物、基于多胺衍生物的聚合物缓蚀剂)的研究现状和发展方向。

关键词：油气管线成膜型缓蚀剂腐蚀缓蚀效率综述

光伏发电最大功率点跟踪交错并联Boost变换器的动力学特性分析

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中国电机工程学报 2013年第6期33卷 38-45,7页

作者：谢玲玲龚仁喜李畸勇广西大学电气工程学院广西省南宁市530004

DC-DC变换器作为光伏发电最大功率点跟踪(maximum power point tracking,MPPT)控制器的核心部分,其动力学特性对系统的性能产生影响。该文基于非线性动力学系统理论,建立了光伏发电最大功率点跟踪(maximum power point tracking,MPPT)... 详细信息

DC-DC变换器作为光伏发电最大功率点跟踪(maximum power point tracking,MPPT)控制器的核心部分,其动力学特性对系统的性能产生影响。该文基于非线性动力学系统理论,建立了光伏发电最大功率点跟踪(maximum power point tracking,MPPT)交错并联Boost变换器的离散迭代映射模型,在此基础上采用分岔图、时域波形图、相轨迹图方法,研究了其动力学特性,并与一般Boost变换器特性进行比较。理论与实验结果均表明,在相同电路参数的情况下,与一般Boost变换器相比,交错并联Boost变换器的稳定域更大,电感电流和电容电压的纹波小、变化幅度小,更适用于光伏发电MPPT。

关键词：交错并联Boost变换器光伏发电最大功率点跟踪离散迭代映射

A Study on Fault Diagnosis of Hydroelectric Generator Based on D-S Evidence Theory

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A Study on Fault Diagnosis of Hydroelectric Generator Based ...