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《史记》考证五则
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作者 杨逢彬 张雨涛 《长江学术》 2024年第3期99-107,共9页
《史记》流传时间久远,篇幅丰富,至今还留存了许多亟待解决的疑难字词问题,例如:“禁不得祠”中,“禁不得”乃一语义复现结构,“禁”可与各类否定词,组成语义复现形式;“乃循从代来功臣”,“循”确诂为“安慰、抚慰”,不必从《汉书》异... 《史记》流传时间久远,篇幅丰富,至今还留存了许多亟待解决的疑难字词问题,例如:“禁不得祠”中,“禁不得”乃一语义复现结构,“禁”可与各类否定词,组成语义复现形式;“乃循从代来功臣”,“循”确诂为“安慰、抚慰”,不必从《汉书》异文改为“修”;“铸钱器”,“钱”当是“铁”的讹字,义为“铸造铁制器具”;“且夫楚唯无强”,“唯无”是文献中常见结构,表示一种假设情况;“数见不鲜”中,“鲜”指新杀的肉食,非指人际关系的新鲜感。以上五处需要回到当时语言环境中,通过足量的书证归纳,运用考察分布等方法,给予更加准确的解释。 展开更多
关键词 《史记》疑难字词 “禁不得” “循” “铸钱器” “唯无” “鲜”
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微管壳式换热器在能量转换循环中的应用 被引量:1
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作者 高娇 丁文杰 +3 位作者 黄洪文 郭海兵 马纪敏 王少华 《强激光与粒子束》 CAS CSCD 北大核心 2023年第11期122-131,共10页
目前,超临界二氧化碳(S-CO_(2))布雷顿循环普遍采用印刷电路板换热器(PCHE)来保证其相对其他能量转换循环的紧凑性优势。PCHE芯体为整体结构,若内部出现泄漏或结垢等问题,很难进行维护与检修。本文提出了一种微管壳式换热器(MSTE),其结... 目前,超临界二氧化碳(S-CO_(2))布雷顿循环普遍采用印刷电路板换热器(PCHE)来保证其相对其他能量转换循环的紧凑性优势。PCHE芯体为整体结构,若内部出现泄漏或结垢等问题,很难进行维护与检修。本文提出了一种微管壳式换热器(MSTE),其结构与传统管壳式换热器类似,但其管径缩小至微通道级。由于MSTE的流道横截面积占总截面积之比较PCHE大,在典型的回热器与冷却器设计工况下,相对PCHE而言,采用MSTE可将体积与质量均减小30%以上。灵敏性分析结果显示,采用本文设计的MSTE结构的回热器与冷却器,回热器冷热流道入口温度升高20℃左右,压缩机入口温度变化均不超过1℃,说明该种结构换热器的换热能力足够支撑能量转换循环的一般工况波动。 展开更多
关键词 微管壳式换热器 超临界二氧化碳 回热器 冷却器
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论大数据背景下的政府“循数”治理 被引量:55
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作者 任志锋 陶立业 《理论探索》 CSSCI 北大核心 2014年第6期82-86,共5页
在大数据背景下,政府"循数"治理,需要树立正确的"循数"治理理念,全面把握大数据的实质,客观评价大数据对政府治理系统的影响,及时将"循数"治理内化到治理举措中;构筑"循数"治理保障体系,为&qu... 在大数据背景下,政府"循数"治理,需要树立正确的"循数"治理理念,全面把握大数据的实质,客观评价大数据对政府治理系统的影响,及时将"循数"治理内化到治理举措中;构筑"循数"治理保障体系,为"循数"治理提供智力支持,建立"一体两翼"的数据中心模式,推进电子政务;提升"循数"治理能力,包括对政务数据的掌控、整合、使用的能力。 展开更多
关键词 大数据 政府 “循数”治理
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弥尔顿对“史诗英雄”的改写——论《失乐园》中“战争英雄”与“循道英雄”的二元对立 被引量:3
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作者 吴玲英 《中南大学学报(社会科学版)》 CSSCI 2016年第1期146-152,共7页
以《伊利亚特》为代表的西方古典史诗将"史诗英雄"传统地定位于"战争英雄",但弥尔顿在史诗《失乐园》里将恶魔撒旦刻画为"战争英雄"。此外,弥尔顿将撒旦设置为史诗主人公"循道英雄"亚当之对敌... 以《伊利亚特》为代表的西方古典史诗将"史诗英雄"传统地定位于"战争英雄",但弥尔顿在史诗《失乐园》里将恶魔撒旦刻画为"战争英雄"。此外,弥尔顿将撒旦设置为史诗主人公"循道英雄"亚当之对敌,并自始至终将"战争英雄"和"循道英雄"置于二元对立。这揭示西方史诗发展史上"英雄"的演变,并暗示,弥尔顿改写了"史诗英雄"。在弥尔顿看来,唯有亚当这样的"循道英雄"才能体现出以"信仰""顺从""谦卑"等美德为核心的英雄品质,才能成为"没有战争的史诗"里的"史诗英雄"。 展开更多
关键词 《失乐园》 “史诗英雄” “战争英雄” “循道英雄” 二元对立
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清代甘肃循化厅司法档案的保存、整理与研究 被引量:2
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作者 李守良 阮兴 靳鹏 《西华师范大学学报(哲学社会科学版)》 2020年第2期23-29,共7页
清代循化厅司法档案这一独特的样本,主要反映了黄土高原和青藏高原交汇处汉、藏、回、撒拉、东乡、保安、土族等部落及族际间的个体与群体纠纷,内容丰富,有典型的民族性、宗教性与边疆性特色。相关研究成果主要集中在两造纠纷的类型、... 清代循化厅司法档案这一独特的样本,主要反映了黄土高原和青藏高原交汇处汉、藏、回、撒拉、东乡、保安、土族等部落及族际间的个体与群体纠纷,内容丰富,有典型的民族性、宗教性与边疆性特色。相关研究成果主要集中在两造纠纷的类型、纠纷裁断的法源、民间与官方的调解与裁断,并重点关注到纠纷解决过程中部落权力、宗教权力和国家权力的互动与博弈。循化厅群体纠纷的状况、纠纷的思想与文化因素、民间调处与官府审判的性质、作用及其相互关系等方面还有进一步挖掘的空间。 展开更多
关键词 清代 化厅 司法档案
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从前四史看“拊(抚)循”的意义 被引量:1
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作者 张青松 《惠州学院学报》 2006年第2期71-74,共4页
现行辞书和古代汉语教材对“拊(抚)循”一词的理解存在分歧,甚至有的注释有欠妥之处。文章对“前四史”中出现的“拊(抚)循”一词作了穷尽性调查,初步探讨了该词的构成和意义,从而证明该词在古代汉语中并无“训练;调度”的义项。
关键词 注解 前四吏
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Structure and functional heterogeneity of soil microbial communities in different farmland types on the Loess Plateau
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作者 XU Chen SU Cuicui +3 位作者 CHEN Yiping MA Jifu WU Junhua JIANG Yao 《地球环境学报》 CSCD 2024年第4期653-664,共12页
Background,aim,and scope Soil microbes are important drivers of nutrient transformation and energy f low.Reclaiming forest land for agricultural use may have profound effects on soil properties and microbial communiti... Background,aim,and scope Soil microbes are important drivers of nutrient transformation and energy f low.Reclaiming forest land for agricultural use may have profound effects on soil properties and microbial communities.However,the response of soil microbial communities to soil reclamation in the dryland agroecosystem is less understood.Therefore,it is necessary to investigate the changes of soil microbial communities driven by land use conversion to promote nutrient cycling in reclaimed farmland.Materials and methods Based on the metagenomic technique,we evaluated the microbial composition and function of the newly created farmland(NF)after reclamation with two types of traditional farmland(slope farmland(SF),checkdam farmland(CF))on the Loess Plateau,and explored the response of nutrient cycling function to dominant genera and soil properties.Results The results showed that Proteobacteria,Actinobacteria,and Acidobacteria were prevalent in the three types of farmlands.Compared with SF and CF,NF increased the relative abundance of Actinobacteria and Nocardioides,as well as genes related to amino acid metabolism and carbohydrate metabolism.The relative abundance of functional genes related to carbon and nitrogen cycling in the NF was higher than that in the traditional farmland(SF and CF).The relative abundance of nutrient cycling functional genes was positively correlated with dominant genera in the three types of farmlands.Except for pH,soil physicochemical factors were negatively correlated with genes related to amino acid metabolism and carbon cycle.Discussion Previous studies have shown that the nutrient conditions of the soil may intensify the competition between the eutrophic and oligotrophic microbial populations.After long-term cultivation and fertilization,the soil properties of traditional farmland were significantly different from those of NF,leading to the differentiation of dominant microbial groups.Microbes usually have functional redundancy to cope with changing environments.Soil microbes in traditional farmland may contain more genes related to replication and repair,cell growth and death,and environmental adaptation in response to disturbances caused by agricultural practices.On the contrary,the NF was less disturbed by agricultural activities,and the soil properties were more similar to forest land,so the carbon and nitrogen cycle function genes were more abundant.The nutrient cycling function was affected by the abundance of microbial dominant groups and soil properties,which may be related to the availability of soil nutrients and agricultural disturbance in different farmlands.Aspects of soil microbial-driven nutrient cycling in agriculture could be regulated in sustainable method.Conclusions The change from forest land to farmland kept more carbon and nitrogen cycling function in the newly created farmland,while long-term agricultural activities have drastically changed the functional structure of traditional farmland,resulting in the nutrient cycling function more concentrated to meet the needs of crop growth.Recommendations and perspectives Hence,it is necessary to apply sustainable agricultural method to regulate microbial-driven nutrient cycling.The insights are meaningful for sustainable agricultural development and land management in arid areas. 展开更多
关键词 METAGENOMICS microbial function FARMLAND nutrient cycling Loess Plateau
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Recent Advances in Transition Metal-Based Catalysts for Electrocatalytic Nitrate Reduction Reaction
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作者 LUO Hongxia CHEN Jun YANG Jianping 《Journal of Donghua University(English Edition)》 CAS 2024年第4期333-348,共16页
The accumulation of excessive nitrate in the atmosphere not only jeopardizes human health but also disrupts the balance of the nitrogen cycle in the ecosystem.Among various nitrate removal technologies,electrocatalyti... The accumulation of excessive nitrate in the atmosphere not only jeopardizes human health but also disrupts the balance of the nitrogen cycle in the ecosystem.Among various nitrate removal technologies,electrocatalytic nitrate reduction reaction(eNO_(3)RR)has been widely studied for its advantages of being eco-friendly,easy to operate,and controllable under environmental conditions with renewable energy as the driving force.Transition metal-based catalysts(TMCs)have been widely used in electrocatalysis due to their abundant reserves,low costs,easy-to-regulate electronic structure and considerable electrochemical activity.In addition,TMCs have been extensively studied in terms of the kinetics of the nitrate reduction reaction,the moderate adsorption energy of nitrogen-containing species and the active hydrogen supply capacity.Based on this,this review firstly discusses the mechanism as well as analyzes the two main reduction products(N_(2)and NH_(3))of eNO_(3)RR,and reveals the basic guidelines for the design of efficient nitrate catalysts from the perspective of the reaction mechanism.Secondly,this review mainly focuses on the recent advances in the direction of eNO_(3RR)with four types of TMCs,Fe,Co,Ni and Cu,and unveils the interfacial modulation strategies of Fe,Co,Ni and Cu catalysts for the activity,reaction pathway and stability.Finally,reasonable suggestions and opportunities are proposed for the challenges and future development of eNO_(3)RR.This review provides far-reaching implications for exploring cost-effective TMCs to replace high-cost noble metal catalysts(NMCs)for eNO_(3)RR. 展开更多
关键词 electrocatalysis nitrate reduction reaction transition metal-based catalyst(TMC) reaction mechanism nitrogen cycle
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Crystalline and amorphous metal sulfide composite electrode materials with long cycle life:Preparation and performance of hybrid capacitors
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作者 DING Ning WANG Siyu +4 位作者 YU Shihua XU Pengcheng HAN Dandan SHI Dexin ZHANG Chao 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1784-1794,共11页
Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realiz... Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities. 展开更多
关键词 crystalline@amorphous heterostructure NiCo2S4@MoS2 hybrid supercapacitor defect design long cycle life
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王念孙“‘脩’、‘循’形近而误”说献疑
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作者 李朝虹 《西南交通大学学报(社会科学版)》 CSSCI 2010年第5期33-37,共5页
王念孙认为典籍中"脩"和"循"常常"形近而误",并将大量的"脩"校改为"循"。但对典籍中"脩"和"循"的致误情况进行统计,发现"脩"几乎都是在表遵循义时被... 王念孙认为典籍中"脩"和"循"常常"形近而误",并将大量的"脩"校改为"循"。但对典籍中"脩"和"循"的致误情况进行统计,发现"脩"几乎都是在表遵循义时被认为由"循"所误,而表其他义时则不被言误,用"形近而误"说无法对此作出合理解释。对大量语言材料进行分析的结果也表明:"脩"与"循"同有遵循义,不烦校改。 展开更多
关键词 王念孙 《读书杂志》
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高等教育“循数治理”的实现路径
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作者 王艳 《中国成人教育》 2018年第22期57-59,共3页
近些年来,随着科学技术快速发展,大数据技术被广泛应用于社会生产生活中的方方面面,大数据时代已经到来。大数据与社会治理相互结合产生的具有丰富内涵的"循数治理"成为高等教育的治理的发展方向。剖析了高等教育"循数治... 近些年来,随着科学技术快速发展,大数据技术被广泛应用于社会生产生活中的方方面面,大数据时代已经到来。大数据与社会治理相互结合产生的具有丰富内涵的"循数治理"成为高等教育的治理的发展方向。剖析了高等教育"循数治理"过程中面临的问题,提出了高等教育"循数治理"的实现路径。 展开更多
关键词 高等教育 教育管理 “循数治理” 大数据技术
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“循行病所”针刺治疗梅核气68例
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作者 吴立雨 葛杜鹃 +2 位作者 刘凯凯 石瑞静 石芳红 《中医临床研究》 2021年第6期83-84,共2页
目的;观察“循行病所”针法治疗梅核气的临床疗效观察。方法:于2019年3月-2019年11月,援疆期间,在缺医少药的条件下,对68例梅核气患者采用“循行病所”针灸治疗,并观察临床疗效。结果:68例患者中,治愈36例,好转28例,无效3例,脱落1例,总... 目的;观察“循行病所”针法治疗梅核气的临床疗效观察。方法:于2019年3月-2019年11月,援疆期间,在缺医少药的条件下,对68例梅核气患者采用“循行病所”针灸治疗,并观察临床疗效。结果:68例患者中,治愈36例,好转28例,无效3例,脱落1例,总有效率95.52%(64/67),治疗后3个月随访,其中治愈患者复发2例,好转患者复发5例。结论:“循行病所”针法治疗梅核气疗效显著,充分体现了调神和得气的双重影响,值得参考与应用。 展开更多
关键词 梅核气 “循行病所”针法 远期疗效 气证^(+)
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焦循《加减乘除释》新探
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作者 魏雪刚 《自然科学史研究》 CSSCI CSCD 北大核心 2022年第4期415-428,共14页
“通儒”焦循的《加减乘除释》是一部重要的算学著作,前人多提及其算理而未展开讨论。文章利用丰富的文献,较全面地梳理了《加减乘除释》的编纂过程,指出焦循编纂思想有一种从“难奥”向“浅近”的颇具重要意义的转变;围绕“加减乘除错... “通儒”焦循的《加减乘除释》是一部重要的算学著作,前人多提及其算理而未展开讨论。文章利用丰富的文献,较全面地梳理了《加减乘除释》的编纂过程,指出焦循编纂思想有一种从“难奥”向“浅近”的颇具重要意义的转变;围绕“加减乘除错综变化”探究了焦循的算理内涵,认为“加减乘除”的重点在辨别盈朒,“错综变化”针对的是运算程序;整理了《九章算术》与“加减乘除”的关系表,并对焦循构建算理的逻辑思路进行了阐释;从乾嘉时期重视算理的学术风气、乘除在算学知识中的核心地位、象数学与算学的关系等方面入手,揭示了焦循算理思想的深厚历史渊源;指出了《加减乘除释》体现在研究方法和研究对象上的积极价值,以及它对易学发展的深刻影响。 展开更多
关键词 乾嘉学术 《加减乘除释》 算理
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“沿循”概念表征形式与概念域成员历史演变
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作者 马梅玉 《集美大学学报(哲学社会科学版)》 2019年第4期102-108,共7页
文章在语义成分恒定的情况下考察汉语"沿循"概念表达表征形式与概念域成员的演变。汉语"沿循"概念的表达既有表征形式的演变,也有概念域成员的演变。其演变呈现出传承性、变化性、演变的同一性等特点,受到语言内部... 文章在语义成分恒定的情况下考察汉语"沿循"概念表达表征形式与概念域成员的演变。汉语"沿循"概念的表达既有表征形式的演变,也有概念域成员的演变。其演变呈现出传承性、变化性、演变的同一性等特点,受到语言内部与外部两方面因素的影响。语言内部因素主要有:汉语由综合性语言到分析性语言类型转变的影响、双音化趋势与韵律的推动、词义系统的不平衡性,外部因素主要是人们语言表达上的喜新厌旧心理。 展开更多
关键词 沿 概念表征形式 概念域成员
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古代循吏治水举要
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作者 郭泽杰 《江西水利科技》 2021年第5期386-390,共5页
古代治水与治国相表里,循吏作为一种古代吏治理想和官吏楷模,两者结合、以古鉴今是一项很有意趣的课题。循吏治水多为一时一事,工程漫漶或湮废不存,不足为训,但其治水经验和精神品格已成为中华民族治水精神的有机构成,值得辩证继承、守... 古代治水与治国相表里,循吏作为一种古代吏治理想和官吏楷模,两者结合、以古鉴今是一项很有意趣的课题。循吏治水多为一时一事,工程漫漶或湮废不存,不足为训,但其治水经验和精神品格已成为中华民族治水精神的有机构成,值得辩证继承、守正创新。 展开更多
关键词 读史“循吏治水” 治水经验 治水品格 治水镜鉴
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三元正极材料清洗废水资源化回收零排放处理工艺 被引量:2
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作者 季宏飞 秦佩 吴晓伟 《当代化工》 CAS 2023年第10期2487-2491,2496,共6页
锂电三元正极材料在清洗过程中产生含有Li^(+)、Al^(3+)、SO_(4)^(2-)、镍钴锰氧化物及少量其他离子的废水,对该三元正极材料清洗废水的资源化回收零排放处理工艺进行了阐述。该废水处理系统涉及的成套工艺包括预处理单元、废水减量化... 锂电三元正极材料在清洗过程中产生含有Li^(+)、Al^(3+)、SO_(4)^(2-)、镍钴锰氧化物及少量其他离子的废水,对该三元正极材料清洗废水的资源化回收零排放处理工艺进行了阐述。该废水处理系统涉及的成套工艺包括预处理单元、废水减量化单元、沉锂单元和制纯水单元。重点对Al^(3+)的去除、膜浓缩、沉锂等关键工艺进行了重点描述,最后通过实际与理论对比分析,达到了预期的设计目标——锂资源得到有效回收、废水实现全部回用。通过对实际案例的相关数据的例举和分析,证明了本套废水处理工艺的可行性和可靠性,为锂电三元正极材料清洗废水的治理提供了典型的参考工艺路线。 展开更多
关键词 三元正极材料 锂资源回收 废水零排放 膜浓缩 蒸发结晶
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A Mode Research of Straw Recycling Based on Circular Agriculture Theory 被引量:11
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作者 冯伟 张利群 +2 位作者 何龙娟 庞中伟 郭淑珍 《Agricultural Science & Technology》 CAS 2011年第12期1921-1924,共4页
Recycling of crop residues resources has become an urgent problem to be addressed in agriculture and rural areas of China.Compared to single use patterns of crop residues resources,crop residues circular agriculture c... Recycling of crop residues resources has become an urgent problem to be addressed in agriculture and rural areas of China.Compared to single use patterns of crop residues resources,crop residues circular agriculture characterized by multi-grade utilization and recycling is more important to improve the added value of crop residues,to enhance product market competitiveness,and to promote scale development and industrialization of crop residues recycling.This paper discussed the basic principles of the development of crop residues circular agriculture mode,and summarized five main crop residues circular agriculture mode. 展开更多
关键词 Crop straw Circular agriculture Multilevel utilization Circular utilization MODE
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Recovery of alumina from circulating fluidized bed combustion Al-rich fly ash using mild hydrochemical process 被引量:16
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作者 杨权成 马淑花 +1 位作者 郑诗礼 张然 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1187-1195,共9页
To utilize CFBC Al-rich fly ash, a mild hydrochemical extraction process was investigated for recovery of alumina. An alumina extraction efficiency of 92.31%was attained using a 45%NaOH solution, an original caustic r... To utilize CFBC Al-rich fly ash, a mild hydrochemical extraction process was investigated for recovery of alumina. An alumina extraction efficiency of 92.31%was attained using a 45%NaOH solution, an original caustic ratio (molar ratio of Na2O to Al2O3 in the sodium aluminate solution) of 25, a molar ratio of CaO to SiO2 in the fly ash of 1.1, a liquid volume to solid mass ratio of 9, a reaction temperature of 280 ℃, and a residence time of 1 h when treating fly ash with an alumina to silica mass ratio (A/S) of 0.78 and an alumina content of 32.43%. Additionally, the alumina leaching mechanism was explored via structural and chemical analysis, which revealed that after alkaline digestion, the main solid phase containing silica was NaCaHSiO4 with a theoretical A/S of zero. 展开更多
关键词 recovery of alumina fly ash phase transformation circulating fluidized bed combustion (CFBC)
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资源型城市产业转型:辽宁省个案 被引量:5
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作者 于立 姜春海 《改革》 CSSCI 北大核心 2005年第11期20-26,共7页
研究东北老工业基地的资源型经济问题可从资源型企业、资源型产业和资源型城市三个角度进行。其中难度最大的是资源型城市的产业转型和可持续发展问题。资源型城市的产业转型是指通过发展接替产业——包括接续产业和替代产业,摆脱原来... 研究东北老工业基地的资源型经济问题可从资源型企业、资源型产业和资源型城市三个角度进行。其中难度最大的是资源型城市的产业转型和可持续发展问题。资源型城市的产业转型是指通过发展接替产业——包括接续产业和替代产业,摆脱原来对不可再生的耗竭性资源的依赖,由原来以资源产业为主向非资源产业为主的转变,促使由单一资源型城市向综合型城市转化。实践表明,利用发展接续产业和发展替代产业的组合搭配,实现“循序渐转”,是资源型城市产业转型的最优方式。 展开更多
关键词 资源型城市 产业转型 辽宁 经济结构 “循序渐转” 资源开发
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Microstructure and mechanical properties of AZ61 magnesium alloy prepared by repetitive upsetting-extrusion 被引量:11
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作者 徐岩 胡连喜 +3 位作者 孙宇 贾建波 姜巨福 马庆国 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第2期381-388,共8页
The process of repetitive upsetting-extrusion (RUE) was used to achieve severe plastic deformation (SPD) for an as-cast AZ61 magnesium alloy in temperature range of 285-380 ℃. The microstructure and mechanical pr... The process of repetitive upsetting-extrusion (RUE) was used to achieve severe plastic deformation (SPD) for an as-cast AZ61 magnesium alloy in temperature range of 285-380 ℃. The microstructure and mechanical properties of the as-cast and RUE processed AZ61 alloys were investigated. The results indicated that homogeneous fine-grained structure with mean grain size of 3.5 μm was obtained as the accumulated true strain in the axial direction increased to 4.28 after three RUE passes at 285 ℃. The dominant reason of grain refinement was considered the dynamic recrystallization induced by strain localization. It was also found that the microstructural evolution was affected by temperature and accumulated deformation. The mechanical properties of RUE processed AZ61 alloys were significantly improved owing to grain refinement. Furthermore, the relationship between deformation parameters and mechanical properties of AZ61 alloy prepared by RUE processing was revealed by tensile tests carried out at room temperature. 展开更多
关键词 AZ61 magnesium alloy repetitive upsetting-extrusion severe plastic deformation groin refinement mechanicalproperties
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