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INVESTIGATION ON MECHANICALLY ALLOYED SUPERSATURATED NANOCRYSTALLINE Al-Ti ALLOYS

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Acta Metallurgica Sinica(English Letters) 1994年第2期7卷 124-128页

作者： FAN Guojiang, quan Mingxiu, hu ZhuangqiInstitute of Metal Research. Chinese Academy of Sciences, Shenyang, China Manuscript received 6 May, 1994

The Al_(100-x)Ti_(x)(x = 5,10,15,35) mixed powders were mechanically alloyed in a planetary bull mill. It was found that the initial composition strongly affects the final productsi a mixture of supersaturated solid solution Al(Ti) and a fee phase for x = 5 and 10; and a single supersaturated solid solution Al(Ti)for x=15 and 35. With inereasing Ti contents from 5at% to 35at%, the grain size of solid solution Al(Ti) decreased from 40nm to 10nm. The results suggest that fast diffusion along nanocrystalline grain boundary is the main alloying process. DSC curves and TEM observation indicate that the solute atom segregation can thermally stabilize the nanocrvstalline solid solutions.

关键词： mechanical alloy ing. fast diffusion thermal stability

Ground State Spins of Bicarbcnes and Binitrenes,Coupled through Electron-Rich Rings

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Chinese Chemical Letters 1999年第11期10卷 937-940页

作者： Hai quan hu Yong Jun LIU Da Cheng FENG Cheng Bu LIU(Institute of Theoretical Chemistry, Shandong University, Jinan 250010)

The ground state spins coupled through electron-rich rings of bicarbenes and binitreneshave been studied at UHF/6-31G* level. The results demonstrate that ferromagnetic couplingexists in these molecules, and electron-... 详细信息

关键词： Electron-rich ring ferromagnetic coupling bicarbene binitrene.

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文化自觉视角下乡村公共空间探析

河南大学学报（社会科学版） 2016年第1期56卷 62-69页

作者：胡全柱浙江师范大学儿童文化研究院暨社会发展研究中心浙江金华321004

乡村公共空间是乡村社会的重要组成部分。从文化自觉视角看,受市场经济和城市化的影响,乡村公共空间呈现出一系列文化不自觉的表征:公共空间强势植入、城市文化霸权、主体偏向和公共性缺失等。重建乡村公共空间需要以"内生"代替"植入",... 详细信息

乡村公共空间是乡村社会的重要组成部分。从文化自觉视角看,受市场经济和城市化的影响,乡村公共空间呈现出一系列文化不自觉的表征:公共空间强势植入、城市文化霸权、主体偏向和公共性缺失等。重建乡村公共空间需要以"内生"代替"植入",以"乡土文化"代替"城市文化",以"主体均衡"代替"主体偏向",以"公共性重建"代替"公共性缺失",只有这样才能建构一个符合乡村社会的公共空间。

关键词：乡村公共空间文化自觉公共性

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秦岭山地5种亚高山草甸的物种多样性研究

西北农林科技大学学报（自然科学版） 2015年第5期43卷 71-78页

作者：窦全虎青海省湟中县林业局青海湟中811600

【目的】研究秦岭山地5种典型亚高山草甸物种的多样性,为该区域亚高山草甸的保护提供依据。【方法】以分布在秦岭火地塘林区、佛坪自然保护区、太白山自然保护区的野青茅(Deyeuxia arundinacea)、赖草(Leymus secalinus)、长穗苔草(Care... 详细信息

【目的】研究秦岭山地5种典型亚高山草甸物种的多样性,为该区域亚高山草甸的保护提供依据。【方法】以分布在秦岭火地塘林区、佛坪自然保护区、太白山自然保护区的野青茅(Deyeuxia arundinacea)、赖草(Leymus secalinus)、长穗苔草(Carex dolichostachya)、早熟禾(Poa annua)、细叶苔草(Carex rigescens)等5种亚高山草甸群落为研究对象,采用样方法进行调查取样,记录5种典型亚高山草甸群落的物种名称、高度、盖度、株数、海拔高度等相关数据,对5种草甸群落的物种组成及其重要值、丰富度、多样性指数和均匀度指数进行对比分析,并进行草甸群落植物物种组成的相似性分析;在太白山自然保护区不同海拔(1 700,2 000,2 300,2 600和2 900m)高度设置样方,调查分析5种草甸群落的物种丰富度及物种多样性随海拔变化的规律。【结果】野青茅、赖草、长穗苔草、早熟禾、细叶苔草5种草甸群落的建群种分别为野青茅、赖草、长穗苔草、早熟禾、细叶苔草。5种亚高山草甸群落的物种丰富度分别为早熟禾草甸(18种)>细叶苔草草甸(15种)>赖草草甸(10种)>长穂苔草草甸(8种)>野青茅草甸(6种),Shannon-Wiener多样性指数H′和Simpson多样性指数D大小依次均为细叶苔草草甸(3.567,0.724)>早熟禾草甸(3.321,0.653)>长穗苔草草甸(2.365,0.584)>赖草草甸(2.247,0.513)>野青茅草甸(1.487,0.456),Pielou均匀度指数J为细叶苔草草甸(0.798)>长穗苔草草甸(0.617)>早熟禾草甸(0.513)>赖草草甸(0.487)>野青茅草甸(0.454)。5种草甸群落中长穗苔草草甸与早熟禾草甸的相似度最高,相似系数为0.222;早熟禾草甸与赖草草甸的相似度最低,相似系数为0.071。随着海拔高度的升高,物种丰富度呈现出先增高再降低的趋势,物种多样性指数变化趋势与之类似。【结论】5种秦岭山地亚高山草甸中,灌木和乔木物种相对较少,其对草甸物种丰富度的影响也相对较小,可以采用人工干预的方法增加物种丰富度,以维持并提高草甸资源的生产力和稳定性。

关键词：秦岭亚高山草甸生物多样性物种丰富度多样性指数

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诗界革命视野中的《清议报》诗歌

河南大学学报（社会科学版） 2016年第4期56卷 79-86页

作者：胡全章河南大学文学院河南开封475001

以1900年2月梁启超揭橥诗界革命旗帜的《汗漫录》发表为界,前后期《清议报》诗歌发生了显著变化。前期以康有为、谭嗣同为压阵大将,后期以梁启超、蒋智由、毋暇、邱炜萲、丘逢甲、高旭等为骨干力量。《清议报》诗歌在题材题旨上体现出... 详细信息

以1900年2月梁启超揭橥诗界革命旗帜的《汗漫录》发表为界,前后期《清议报》诗歌发生了显著变化。前期以康有为、谭嗣同为压阵大将,后期以梁启超、蒋智由、毋暇、邱炜萲、丘逢甲、高旭等为骨干力量。《清议报》诗歌在题材题旨上体现出强烈的现实批判精神、炽烈的救亡启蒙情怀、深挚的忧国忧民情结和夺目的革新图强思想光芒,大量诗篇宣扬了平权、共主、独立、自由、民权、女权等近代启蒙观念,乃至倡导破坏、暗杀、扑满、反帝等民族革命思想主张。形式方面,既重视篇幅较长、容量更大、诗体更为解放、语言通俗易懂的歌行体和歌诗,又注意保留"古风格",使其不失为"诗人之诗"。较诸戊戌前的"新学诗"试验,《清议报》诗歌虽大量使用"新名词",但已无晦涩难懂之病;此前"新学诗"中大量出现的宗教性"新名词",逐渐为反映西洋近代政教文明和科技文明的"新名词"所取代。

关键词：诗界革命《清议报》 “诗文辞随录” 梁启超蒋智由

Causes and global,regional,and national burdens of traumatic brain injury from 1990 to 2019

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Chinese Journal of Traumatology 2024年第6期27卷 311-322页

作者： Xiao-Fei huang Shuai-Feng Ma Xu-Heng Jiang Ren-Jie Song Mo Li Ji Zhang Tian-Jing Sun quan hu Wen-Rui Wang An-Yong Yu He Li Department of Emergency Surgery The Second Affiliated Hospital of Anhui Medical UniversityHefei230601China Department of Emergency Affiliated Hospital of Zunyi Medical UniversityZunyi563003Guizhou provinceChina

Purpose:Traumatic brain injury(TBI),currently a major global public health problem,imposes a significant economic burden on society and *** aimed to quantify and predict the incidence and severity of TBI by analyzing its incidence,prevalence,and years lived with disability(YLDs).The epidemiological changes in TBI from 1990 to 2019 were described and updated to provide a reference for developing prevention,treatment,and incidence-reducing measures for ***:A secondary analysis was performed on the incidence,prevalence,and YLDs of TBI by sex,age group,and region(n=21,204 countries and territories)between 1990 and 2019 using the Global Burden of Diseases,Injuries,and Risk Factors Study *** in the age-standardized incidence rate due to underlying causes of TBI and proportions of minor and moderate or severe TBI were also ***:In 2019,there were 27.16 million(95%uncertainty intervals(UI):23.36-31.42)new cases of TBI worldwide,with age-standardized incidence and prevalence rates of 346 per 100,000 population(95%UI:298-401)and 599 per 100,000 population(95%UI:573-627),*** 1990 to 2019,there were no significant trends in global age-standardized incidence(estimated annual percentage changes:-0.11%,95%UI:-0.18%--0.04%)or prevalence(estimated annual percentage changes:0.01%,95%UI:-0.04%-0.06%).TBI caused 7.08 million(95%UI:5.00-9.59)YLDs in 2019,with age-standardized rates of 86.5 per 100,000 population(95%UI:61.1-117.2).In 2019,the countries with higher incidence rates were mainly distributed in Central Europe,Eastern Europe,and *** 2019 global age-standardized incidence rate was higher in males than in *** 2019 global incidence of moderate and severe TBI was 182.7 per 100,000 population,accounting for 52.8%of all TBI,with falls and road traffic injuries being the main causes in most ***:The incidence of moderate and severe TBI was slightly higher in 2019,and TBI still accounts for a signi

关键词： Traumatic brain injury Global health Burden of disease

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基于BP神经网络的词义消歧模型

计算机工程与应用 2006年第12期42卷 187-189,203页

作者：谢芳胡泉华中师范大学计算机科学系武汉430079

词义消歧在自然语言处理中一直是一个难点问题,同时,也是很多领域都需要解决的一个重要环节。文章首先介绍了目前一些常用词义消歧方法的特点和这些方法的研究进展,并在此基础上探讨了一种基于BP神经网络和统计方法相结合的有导词义消... 详细信息

词义消歧在自然语言处理中一直是一个难点问题,同时,也是很多领域都需要解决的一个重要环节。文章首先介绍了目前一些常用词义消歧方法的特点和这些方法的研究进展,并在此基础上探讨了一种基于BP神经网络和统计方法相结合的有导词义消歧模型,最后详细讲解了BP神经网络原理,并对使用这种混合人工智能的消歧模型的可能性和优越性进行了讨论。

关键词：词义消歧基于统计 BP神经网络语料库

Effects of micrite microtextures on the elastic and petrophysical properties of carbonate reservoirs

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Applied Geophysics 2019年第4期16卷 399-413,559页

作者： Pan Jian-Guo Deng Ji-Xin Li Chuang Wang Hong-Bin Zhang hu-quan Zhao Jian-Guo Tang Gen-Yang Research Institute of Petroleum Exploration&Development-Northwest PetroChinaLanzhou730020China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation CUTChengdu 610059China College of Geophysics Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Petroleum Resources and Prospecting CUP(Beijing)Beijing 102249China.

Apparent differences in sedimentation and diagenesis exist between carbonate reservoirs in different areas and affect their petrophysical and elastic *** elucidate the relevant mechanism,we study and analyze the characteristics of rock microstructure and elastic properties of carbonates and their variation regularity using 89 carbonate samples from the different areas The results show that the overall variation regularities of the physical and elastic properties of the carbonate rocks are controlled by the microtextures of the microcrystalline calcite,whereas the traditional classification of rock-and pore-structures is no longer *** micrite microtextures can be divided,with respect to their morphological features,into porous micrite,compact micrite,and tight *** the micrites evolves from the first to the last type,crystal boundaries are observed with increasingly close coalescence,the micritic intercrystalline porosity and pore-throat radius gradually decrease;meanwhile,the rigidity of the calcite microcrystalline particle boundary and elastic homogeneity are *** a result,the seismic elastic characteristics,such as permeability and velocity of samples,show a general trend of decreasing with the increase of *** low-porosity rock samples(φ<5%)dominated by tight micrite,the micritic pores have limited contributions to porosity and permeability and the micrite elastic properties are similar to those of the rock *** such cases,the macroscopic physical and elastic properties are more susceptible to the formation of cracks and dissolution pores,but these features are controlled by the pore *** pore aspect ratio can be used as a good indication of pore *** bulk modulus aspect ratio for dissolution pores is greater than 0.2,whereas that of the intergranular pores ranges from 0.1 to *** porous and compact micrites are observed to have a bulk modulus aspect ratio less than 0.1,whereas the ratio of the tigh

关键词： carbonate rock micrite microtextures rock physical properties petrophysical properties pore aspect ratio

Microstructural evolution of 2026 aluminum alloy during homogenization

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Journal of Central South University 2018年第3期25卷 490-498页

作者： JIANG Ding-bang PAN Qing-lin huANG Zhi-qi hu quan LIU Zhi-ming School of Materials Science and Engineering Central South UniversityChangsha 410083China Guangdong Fenglv Aluminum Company Ltd Foshan 528133China

The microstructural evolution of 2026 aluminum alloy during homogenization treatment was investigated by optical microscopy(OM),scanning electron microscopy(SEM),energy dispersive X-ray spectrometry(EDS),differential scanning calorimetry(DSC)and X-ray diffraction(XRD).The results show that severe dendritic segregation exists in the as-cast 2026 alloy and the main secondary phases at grain boundary are S(Al2CuMg)andθ(Al2Cu)*** Cu,Mg and Mn distribute unevenly from grain boundary to the inside of as-cast *** the increase of homogenization temperature or the prolongation of holding time,the residual phases gradually dissolve into the matrixα(Al)and all the elements become more *** to the results of microstructural evolution,differential scanning calorimetry and X-ray diffraction,the optimum homogenization parameter is at 490°C for 24 h,which is consistent with the result of homogenization kinetic analysis.

关键词： 2026 aluminum alloy dendritic segregation homogenization microstructure evolution homogenization kinetics