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Thinking about Value Realization of Ecological Products under the Background of Urban-rural Integration in Chengdu“Western Control”Area
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作者 zhang xuequan zhang Yi 《Journal of Landscape Research》 2023年第2期59-62,共4页
Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural developmen... Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural development in the new era will realize the balanced development of urban and rural areas and give full play to the value of rural ecological resources through the“powerful combination”of urban and rural areas.To realize the urban-rural integration and high-quality rural development in Chengdu“western control”area,it is necessary to enhance the awareness of ecological resources and ecological products,and carry out unified planning of ecological infrastructure,ecological material products and ecological service products in the whole“western control”area.Meantime,ecological restoration must be carried out scientifically,and scene design for value transformation of ecological products should be implemented innovatively. 展开更多
关键词 Western control Urban-rural integration Ecological products Ecological value transformation
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Practical Teaching Design of Ecotourism Course under the Construction of Park Cities:A Case Study of Qinglong Lake Ecological Wetland Park
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作者 zhang xuequan ZHAN Yi 《Journal of Landscape Research》 2023年第3期75-78,84,共5页
The construction of park cities makes it possible for the popularization of ecotourism,and lays resource conditions and product foundation for the practical teaching of ecotourism course.In this paper,natural ecologic... The construction of park cities makes it possible for the popularization of ecotourism,and lays resource conditions and product foundation for the practical teaching of ecotourism course.In this paper,natural ecological resources and ecological leisure and recreation in Qinglong Lake Ecological Wetland Park were analyzed,and a series of practical teaching projects can be designed based on ecological cognition education,ecological responsibility,ecological experience,ecological environmental protection publicity and ecological tourism scenic spot management,as well as the teaching requirements of ecotourism course. 展开更多
关键词 Park city ECOTOURISM Curriculum practice teaching
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高容量富锂锰基正极材料的研究进展 被引量:2
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作者 王俊 张学全 +1 位作者 刘亚飞 陈彦彬 《储能科学与技术》 CAS CSCD 北大核心 2022年第10期3051-3061,共11页
层状富锂锰基材料(LMR)凭借其高比容量(>250 mAh/g)和低成本等优点,有望成为新一代锂离子电池用正极材料。从该材料发现至今已有将近30年的时间,却始终没有实现真正商业化应用,主要原因包括:循环过程中,Mn^(3+)迁移进入锂空位,使层... 层状富锂锰基材料(LMR)凭借其高比容量(>250 mAh/g)和低成本等优点,有望成为新一代锂离子电池用正极材料。从该材料发现至今已有将近30年的时间,却始终没有实现真正商业化应用,主要原因包括:循环过程中,Mn^(3+)迁移进入锂空位,使层状结构向尖晶石结构转变,导致平均放电电压持续降低,造成能量损失严重且给电池管理带来巨大的挑战;Li_(2)MnO_(3)低的电子电导率使LMR材料具有差的倍率性能;较低的电极密度,造成材料的体积能量密度较低;此外,LMR材料需要在高电压下(>4.55 V)才能发挥高容量,但高电压下电解液容易氧化分解,同时伴随着晶格氧被氧化为O_(2)逸出,以上问题严重地影响了其商业化进程。本文基于多年来LMR材料的研究开发成果,综述了近年来LMR材料在充放电机理认识、前驱体工艺路线选择、体相掺杂、表面包覆、液相和气相后处理的作用效果和改性机理,以及O2/O3复合结构、单晶结构等新型特殊结构设计等方面的研究进展,并对LMR材料未来的发展方向和商业化前景进行展望,助力富锂锰基材料的产业化开发。 展开更多
关键词 富锂锰基材料 充放电机理 改性 后处理
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粉煤灰胶体隔离控制技术在花山矿复杂火区中的应用 被引量:1
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作者 杨平 梁国栋 +2 位作者 于贵生 张学权 段滔 《煤矿安全》 CAS 北大核心 2020年第8期82-86,共5页
攀枝花花山煤矿4238工作面火灾先后采用整个四采区大范围封闭、逐步缩封火区相关联巷道、火区灌注液态二氧化碳降温、无机材料充填等方法进行治理,但均未有效控制火情,随着时间推移,火势逐步向上部蔓延,而后发展成+1 030水平四采火区。... 攀枝花花山煤矿4238工作面火灾先后采用整个四采区大范围封闭、逐步缩封火区相关联巷道、火区灌注液态二氧化碳降温、无机材料充填等方法进行治理,但均未有效控制火情,随着时间推移,火势逐步向上部蔓延,而后发展成+1 030水平四采火区。针对该种极复杂火区,提出分区隔离控制技术,即以电厂燃烧废物资源利用化粉煤灰为主要原料形成的降温、惰化、堵漏效果显著的粉煤灰复合胶体为灌浆材料,通过施工辅助治理巷道,向4238工作面回风方向相关联主要巷道施工注浆钻孔,利用钻孔压注粉煤灰胶体堆积充填材料,将4238工作面火区与4236边上山及火区外围巷道隔离分区域控制,再对各分区逐一治理,最终4238工作面及采空区内CO消失,达到启封标准,取得阶段性灭火效果,结果表明:粉煤灰复合胶体隔离技术能够快速高效地处理大范围火区及处于扩散、蔓延状态的复杂火情。 展开更多
关键词 粉煤灰胶体 复杂火区 注浆充填 隔离控制 防灭火
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近距离煤层群外延火区灭火技术 被引量:1
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作者 段西凯 梁国栋 +3 位作者 于贵生 张学权 段涛 冯大超 《煤矿安全》 CAS 北大核心 2019年第11期76-79,共4页
为了消灭由4238工作面发泡材料充填不当导致发火并蔓延成状态极其复杂的+1030水平四采火区,根据矿井正压通风与倾斜近距离煤层群赋存特点,制订了"先闭后缩再治、先降温再充填、先核心后外围、以隔离火区保障生产接替为优先目标&qu... 为了消灭由4238工作面发泡材料充填不当导致发火并蔓延成状态极其复杂的+1030水平四采火区,根据矿井正压通风与倾斜近距离煤层群赋存特点,制订了"先闭后缩再治、先降温再充填、先核心后外围、以隔离火区保障生产接替为优先目标"的综合灭火方针,采用正压火区远距离封闭与逐步缩封、新型无机材料巷道充填与小断面恢复、移动式液态二氧化碳井下直注、核心火区下施工措施巷等一系列灭火措施对该种外延火区进行治理。结果表明:火势得到了有效地控制,取得了阶段性灭火成果,但外延火区状态依然较为脆弱,后续进一步采取粉煤灰复合胶体灌注措施,逐次充填火区核心与外围区域内巷道,隔离火区掩护下水平掘进与接替,达到了火区治理的最终目的。 展开更多
关键词 正压通风 倾斜煤层 近距离煤层 外延火区 灭火
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JPEG-LS码率控制算法改进及硬件实现 被引量:1
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作者 陈聪 张学全 周盛雨 《空间科学学报》 CAS CSCD 北大核心 2018年第6期944-952,共9页
JPEG-LS码率控制算法是一种基于上下文建模的无损/近无损图像压缩标准,具有实现方法简单、占用资源少等优点,适用于卫星图像压缩等硬件资源有限的场合.该算法在近无损压缩模式下码率不可控制.在对JPEGLS算法进行分析的基础上,提出一种... JPEG-LS码率控制算法是一种基于上下文建模的无损/近无损图像压缩标准,具有实现方法简单、占用资源少等优点,适用于卫星图像压缩等硬件资源有限的场合.该算法在近无损压缩模式下码率不可控制.在对JPEGLS算法进行分析的基础上,提出一种新的基于动态码率表的JPEG-LS码率控制算法,并将新算法应用于硬件设计中.测试结果表明,新算法比现有算法码率控制精度更高,压缩后恢复图像信噪比及结构相似比更高.将该算法在Xilinx Virtex4平台上实现,最高运行频率达60 MHz,可以满足星载系统对图像压缩的需求. 展开更多
关键词 JPEG-LS 星载图像压缩 码率控制
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Landscape Design Talents' Knowledge and Ability Structure Based on Industry Demands
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作者 zhang xuequan 《Journal of Landscape Research》 2016年第6期135-136,141,共3页
Knowledge transference and ability training are 2 standing points and starting points for the industry demands-oriented talent cultivation of modern higher education.In terms of landscape design knowledge,the landscap... Knowledge transference and ability training are 2 standing points and starting points for the industry demands-oriented talent cultivation of modern higher education.In terms of landscape design knowledge,the landscape design industry requires 3 major knowledge modules,namely basic knowledge and theories,professional knowledge,and relevant knowledge;in terms of ability,it also requires 3 major ability modules,namely computer-aided design(CAD),design performance ability and ability of making conception,and each of them includes many specific knowledge points and ability points.It is important for such teaching processes as real question and proposition teaching,studio teaching and project-led teaching to propose a dual-track talent cultivation scheme focusing on both theoretical knowledge and practical ability according to the needs of landscape design industry.Moreover,it is imperative to arrange relevant courses and curriculum group that reflect knowledge and ability demands,as well as practicing courses or comprehensive design projects based on ability structure. 展开更多
关键词 Knowledge and ability Landscape design Industrial demands Talent cultivation
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Ability Training of Landscape Architecture Talents
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作者 zhang xuequan ZHAN Yi 《Journal of Landscape Research》 2016年第1期89-90,共2页
The paper analyzed orientations and requirements of landscape architecture talent training in domestic and international academic fields, and proposed that training of landscape architecture talents should attach more... The paper analyzed orientations and requirements of landscape architecture talent training in domestic and international academic fields, and proposed that training of landscape architecture talents should attach more importance to the establishment and optimization of the discipline, cultivate talents capable of solving realistic environmental and ecological problems, so as to cultivate inter-disciplinary talents from multiple dimensions. 展开更多
关键词 Landscape architecture DISCIPLINE ABILITY
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Lanthanide complexes mediated coordinative chain transfer polymerization of conjugated dienes 被引量:2
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作者 WANG Feng LIU Heng +1 位作者 HU YanMing zhang xuequan 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第9期1286-1294,共9页
Tremendous advances has been witnessed in the past few years in the lanthanide complexes mediated coordinative chain transfer polymerization(CCTP) of conjugated dienes. CCTP features catalyst economy, well-controlling... Tremendous advances has been witnessed in the past few years in the lanthanide complexes mediated coordinative chain transfer polymerization(CCTP) of conjugated dienes. CCTP features catalyst economy, well-controlling over both microstructure and architecture of the resulting polymers, and accessibility for novel(co)polymers. This review highlights the recent progresses made in the field of CCTP of dienes. After a brief introduction, the body of this review is divided into three parts:(1) principle of CCTP;(2) coordinative chain transfer homopolymerization of dienes;(3) coordinative chain transfer copolymerization of dienes.At the end, we present some challenges remaining in this area and our personal opinion regarding where this field should continue to develop. CCTP represents a novel strategy to prepare polydiene synthetic rubbers with controlled high molecular weight and narrow molecular weight distribution, which has reached the practical industrial application level, demonstrating a great potential in industrialization. 展开更多
关键词 链转移 聚合物 建筑群 CCTP 微观结构 合成橡胶 应用程序 高分子
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Morphology and Properties of PP In-reactor Alloys Prepared with a MgCl2/TiCl4/Diisobutyl Phthalate/Phosphate Tris-methylphenyl Ester Catalyst System 被引量:1
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作者 zhang Chunyu DONG Bo +2 位作者 zhang Hexin HU Yanming zhang xuequan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2018年第1期145-150,共6页
关键词 催化剂系统 反应堆 PP 合金 直接存储器存取 形态学 扫描电子显微镜 性质
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