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Water scaling predication for typical sandstone geothermal reservoirs in the Xi'an Depression
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作者 Shuai Ma Yinke Yang +1 位作者 Xinyan Lei Bin Yue 《Energy Geoscience》 2023年第4期128-138,共11页
The Xi'an Depression in the Guanzhong Basin of western China has been suggested to contain geothermal resources that could aid China in achieving carbon neutrality and optimizing energy structure.However,the high ... The Xi'an Depression in the Guanzhong Basin of western China has been suggested to contain geothermal resources that could aid China in achieving carbon neutrality and optimizing energy structure.However,the high concentration of total dissolved solids(TDS)and scale-forming ions in geothermal water from the depression causes severe scaling problems in harvesting geothermal energy.To reduce scale-related problems,accurate identification of scale types and prediction of scaling during geothermal energy utilization are crucial.This study starts with identifying the types and trends of scaling in the study area,using index-based discriminant methods and hydrogeochemical simulation to calculate and analyze the mineral saturation index of water samples from some wellheads and of reconstructed fluid samples of geothermal reservoirs.The results indicate that the scales are mostly calcium carbonate scales rather than sulfate scales as a result of temperature changes.Several portions of the geothermal water systems are found to have distinct mineral scaling components.Quartz and chalcedony are formed in low temperature areas,while carbonate minerals are in high temperature areas.Despite the low iron content of geothermal water samples from the study area,scaling is very common due to scaling-prone iron minerals.The findings can be used to evaluate geothermal drainage systems and guide anti-scaling during geothermal energy utilization in similar settings. 展开更多
关键词 xi'an Depression Geothermal water SANDSTONE SCALinG Hydrogeochemical modeling
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Research on Spatial Development of Xi'an Modern Urban Industrialization
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作者 魏琰 《海外英语》 2015年第6期277-279,共3页
As the Westernization Movement developing in the 1860 s, China began to introduce and learn western science and technology to develop modern military industry and civilian industry. In modern history, Xi'an went t... As the Westernization Movement developing in the 1860 s, China began to introduce and learn western science and technology to develop modern military industry and civilian industry. In modern history, Xi'an went through the Xi 'an capital's industrial embryonic form in the late Qing dynasty and urban industrialization construction during the period of the Republic of China so that it converted gradually from a trade city for Chinese traditional handicrafts under the background of the feudal society to a city in the industrial society where machine were used for production. 展开更多
关键词 MODERN Xi’an inDUSTRIALIZATION EVOLUTION
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Dynamic Analysis of Coupling Relationship between Economic Development and Ecological Environment Based on Entropy Method——A Case Study of Xi'an City 被引量:1
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作者 YU Feng-ming DU Zhong-chao ZHOU Du-hui 《Meteorological and Environmental Research》 CAS 2011年第9期62-66,76,共6页
[Objective] The aim was to study the coupling relationship between economic development and ecological environment. [Method] Firstly, the evaluation index system for the coupling system of economic development and eco... [Objective] The aim was to study the coupling relationship between economic development and ecological environment. [Method] Firstly, the evaluation index system for the coupling system of economic development and ecological environment in Xi’an City was established, then the dynamic variation of coupling relationship between economic development and ecological environment in Xi’an City from 2001 to 2010 was analyzed by using entropy method, finally some corresponding suggestions were put forward according to the problems in the current development model. [Result] The economic development and ecological environment of Xi’an have made a significant upgrading and improvement from 2001 to 2010, namely showing a stable upward trend on the whole, and were in a well-coordinated development state in 2010. However, the development level of ecological environment obviously lagged behind economic development level. In addition, there were obvious differences in the development rate of sub-systems, that is, economic efficiency and economic level developed rapidly, while the carrying capacity of ecological environment and economic vitality grew slowly and unstably. [Conclusion] The research could provide theoretical bases for the establishment of strategies for the coordinated development economy and environment in Xi’an City. 展开更多
关键词 Entropy method Economic development Ecological environment xi'an City China
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Research center of biomanufacturing in Xi'an Jiaotong University 被引量:1
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作者 Ling Wang Dichen Li +1 位作者 Jiankang He Bingheng Lu 《Bio-Design and Manufacturing》 SCIE 2018年第4期280-288,共9页
Xi'an Jiaotong University (XJTU)has carded out the research of additive manufacturing (AM)since 1993,who is one of the earliest institutes majoring in AM.After 20years of effort,XJTU has made great progress on the... Xi'an Jiaotong University (XJTU)has carded out the research of additive manufacturing (AM)since 1993,who is one of the earliest institutes majoring in AM.After 20years of effort,XJTU has made great progress on the additive manufacturing of polymer,metals,ceramics,composite materials and intelligent materials.XJTU has established a research team that features the engineering application of rapid manufacturing system. 展开更多
关键词 xi'an Jiaotong UNIVERSITY
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Evaluation of urban underground space resources using a negative list method: Taking Xi'an City as an example in China 被引量:7
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作者 Mao-sheng Zhang Hua-qi Wang +3 位作者 Ying Dong Lin Li Ping-ping Sun Ge Zhang 《China Geology》 2020年第1期124-136,共13页
Utilization of urban underground space has become a vital approach to alleviate the strain on urban land resources,and to optimize the structure and pattem of the city.It is also very important to improve the city env... Utilization of urban underground space has become a vital approach to alleviate the strain on urban land resources,and to optimize the structure and pattem of the city.It is also very important to improve the city environment,build livable city and increase the capacity of the city.Based on the analysis of existing evaluation methods and their problems,a method for evaluating underground space resources based on a negative list of adverse factors affecting underground space development is proposed,to be primarily used in urban planning stages.A list of the adverse factors is established,including limiting factors,constraining factors and influencing factors.Taking Xi'an as an example,using a geographical information system platform,a negative list of adverse factors for the underground space resources in Xi'an City are evaluated,and preventive measures are proposed.Natural resources,exploitable resources,and the potential growth of exploitable underground space resources are evaluated.Underground space assessment in the different development stages of the city,collaborative utilization and safety evaluation for multiple subsurface resources,environmental impact and assessment,as well as evaluation methods based on big data and intelligent optimization algorithms are all discussed with the aim of serving city planning and construction. 展开更多
关键词 Urban geology Negative list Natural resources for underground space Exploitable resources for underground space 3D geological structure model GIS platform Urban geological survey engineering xi'an City Shaanxi Province China
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Effects of urban grass coverage on rainfall-induced runoff in Xi'an loess region in China
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作者 Jing Li, Zhan-bin Li +2 位作者 Meng-jing Guo Peng Li Sheng-dong Cheng 《Water Science and Engineering》 EI CAS CSCD 2017年第4期320-325,共6页
In this study, laboratory rainfall simulation experiments were conducted to investigate the regulatory effects of grass coverage on rainfallrunoff processes. A total of 80 grass blocks planted with well-grown manilagr... In this study, laboratory rainfall simulation experiments were conducted to investigate the regulatory effects of grass coverage on rainfallrunoff processes. A total of 80 grass blocks planted with well-grown manilagrass, together with their root systems, were sampled from an eastern suburban area of Xi'an City in the northwest arid area of China and sent to a laboratory for rainfall simulation experiments. The runoff and infiltration processes of a slope with different grass coverage ratios and vegetation patterns were analyzed. The results show that the runoff coefficient decreases with the increase of the grass coverage ratio, and the influence of grass coverage on the reduction of runoff shows a high degree of spatial variation. At a constant grass coverage ratio, as the area of grass coverage moves downward, the runoff coefficient, total runoff,and flood peak discharge gradually decrease, and the flood peak occurs later. With the increase of the grass coverage ratio, the flood peak discharge gradually decreases, and the flood peak occurs later as well. In conclusion, a high grass coverage ratio with the area of grass coverage located at the lower part of the slope will lead to satisfactory regulatory effects on rainfall-induced runoff. 展开更多
关键词 Rainfall simulation URBAN vegetation in arid area RAinFALL-RUNOFF process Regulatory effect xi'an LOESS REGION
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Study on Ground Fissures and Land Subsidence Induced by Seepage Deformation in Xi'an
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作者 Zhang Jianjun Zhang Hexin +3 位作者 Zhang Maosheng Tao Hong Dong Yin Xu Chaomei 《Meteorological and Environmental Research》 CAS 2018年第6期53-61,共9页
There are lots of theories about the causation of ground fissures in Xi’an,such as the tectonics theory,the excessive groundwater exploitation theory and the compositive theory. Based on the construction of the geolo... There are lots of theories about the causation of ground fissures in Xi’an,such as the tectonics theory,the excessive groundwater exploitation theory and the compositive theory. Based on the construction of the geologic environment monitoring network in Guanzhong urban agglomeration,the latest survey of ground fissures and land subsidence in Yuhuazhai in Xi’an shows that the extensive piping and quicksand in self-supply wells is a factor to induce ground fissures and land subsidence. It is suggested that the seepage deformation caused by high hydraulic gradient leads to sand gushing and changes some aquifers into the composite aquifer,which is the main factor to induce ground fissures and land subsidence. The development characteristics of ground fissures and land subsidence caused by seepage deformation were summarized. The results will supply new schemes and methods for the causation of land subsidence and ground fissures in Xi’an and lay out a clear road map of measures to control land subsidence and ground fissures. 展开更多
关键词 Seepage deformation Land subsidence Ground fissures xi'an Composite aquifer
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Climate Characteristics of High Temperature Weather in Xi'an City in Recent 59 Years
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作者 MENG Xiao-rong YANG Xiao-chun +1 位作者 Qu Jing JIN Li-na 《Meteorological and Environmental Research》 CAS 2011年第9期43-46,共4页
[Objective] The aim was to study the characteristics of high temperature in Xi’an City over the last 59 years. [Method] By dint of daily highest temperature in the Xi’an observatory, the climate characteristics of h... [Objective] The aim was to study the characteristics of high temperature in Xi’an City over the last 59 years. [Method] By dint of daily highest temperature in the Xi’an observatory, the climate characteristics of high temperature at different intensities and the high attitude circulation were studied by statistical method. [Result] Over the last 59 years, there were 22.95 high temperature days each year on average in Xi’an City, which occurred from the last ten days of April to the first ten days of September. Most high temperature days occurred in the last ten days of July, followed by that in the last ten days of June. There were two peak values in the last ten days of June and last ten days of July when temperature ≥38.0 ℃. For the hottest day, it occurred most in the last twenty days of June, followed by July, and rarely in August. The interannual changes in the high temperature day, hot day and hottest day showed one-little and one-much trend. It was much from 1950s to 1960s, from 1970s to 1980s and then grew more after 1990s. The annual extreme highest temperature took place in the last twenty days of June, and then in the last ten days of July. Its interannual changes showed high-low-high trend. The high temperature appeared most often in July and also lasted for the longest duration. The hot day lasted for two days. The hottest days of ≥40.0 ℃ were very rare. The circulation of high temperature generally fell into one of four categories: continental high pressure controlling type, subtropical high controlling type, strip high pressure controlling type and northwest airstream controlling type. [Conclusion] The study provided references for the forecast and pre-warning of high temperature. 展开更多
关键词 High temperature Changes characteristics Circulation characteristics xi'an City China
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Space Structuring of the Northern Foot of the Qinling Mountains(Xi'an Section) based on Landscape City
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作者 XIAO Zhetao 《Journal of Landscape Research》 2014年第2期11-14,共4页
Northern foot of the Qinling Mountains(Xi'an Section) is a transitional section between the Qinling Mountains and Xi'an City, so it has great ecological signifi cance. On the basis of sorting out landscape cit... Northern foot of the Qinling Mountains(Xi'an Section) is a transitional section between the Qinling Mountains and Xi'an City, so it has great ecological signifi cance. On the basis of sorting out landscape city, space structuring of the northern foot of the Qinling Mountains was studied within the theoretical framework of landscape city, it was disclosed that northern foot of the Qinling Mountains was a signifi cant ecological screen for the landscape city spatial pattern of Xi'an, and an important carrier for its "mountain, water and city" cultures. Then, fi ve infl uence factors for the space structuring of the study area were given, and basic contents of the space structuring analyzed from fi ve perspectives of spatial structure, spatial form, ecological environment, integration of regional spaces, historical and cultural context, so as to explore ecological conservation and moderate utilization of the northern foot of the Qinling Mountains from the perspective of space structuring. 展开更多
关键词 Landscape city Space structuring Northern foot of the Qinling Mountains Xi’an
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Construction of Xi'an ecological old-age care community in the new urbanization
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作者 JIAN Ai 《Ecological Economy》 2018年第2期123-128,共6页
The new urbanization is an important carrier of ecological civilization construction, and ecological old-age care is the concrete manifestation of the perfect combination of the two, the proper meaning of the new urba... The new urbanization is an important carrier of ecological civilization construction, and ecological old-age care is the concrete manifestation of the perfect combination of the two, the proper meaning of the new urbanization connotation and an inevitable trend of its development. Based on the analysis of the connotation and relationship between the new urbanization and ecological old-age care, together with the current situation and existing problems of the current nursing institutions and ecological old-age care in Xi'an area, this paper discusses the major issues that should be noticed when constructing the ecological old-age care community in Xi'an and three main construction modes. 展开更多
关键词 new urbanization Xi’an ecological old-age care community
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机动车限行对西安市空气质量的影响及其模型分析
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作者 胡恬 娄春辉 吴雅睿 《大气与环境光学学报》 CAS CSCD 2024年第3期333-341,共9页
近年来,空气污染已成为限制西安城市人居环境质量提升的重要因素之一。当地政府采取了一系列的措施进行空气污染治理,其中机动车限行政策以其可实施性强、公共投入较少、简单易行等特点而最受青睐。在分析2016―2020年间西安市空气质量... 近年来,空气污染已成为限制西安城市人居环境质量提升的重要因素之一。当地政府采取了一系列的措施进行空气污染治理,其中机动车限行政策以其可实施性强、公共投入较少、简单易行等特点而最受青睐。在分析2016―2020年间西安市空气质量变化趋势的基础上,运用R语言针对相关影响因子(限行政策、平均风速、相对湿度和平均温度)与空气质量之间的关系建立了广义相加模型,并进行了拟合分析和相关性检验,结果表明机动车限行政策与西安市空气质量改善具有较明显的相关性。 展开更多
关键词 限行 机动车 空气质量 西安市
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浅谈西安的包容精神——以周秦汉唐为例
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作者 陈正奇 柯扬 《西安文理学院学报(社会科学版)》 2024年第2期82-88,共7页
周、秦、汉、唐均建都古城长安(今西安)。周人以礼仪贤德包容四海,制礼作乐,统治天下。秦人以宽广的胸怀招贤纳士,秋风扫叶,创建基制,震慑四方。汉人以“大一统”的梦想构筑帝国,始开丝路,融合匈奴,汉匈和睦,天下归一。唐人以开放的心... 周、秦、汉、唐均建都古城长安(今西安)。周人以礼仪贤德包容四海,制礼作乐,统治天下。秦人以宽广的胸怀招贤纳士,秋风扫叶,创建基制,震慑四方。汉人以“大一统”的梦想构筑帝国,始开丝路,融合匈奴,汉匈和睦,天下归一。唐人以开放的心态、宏伟的气势以前朝为鉴,创大唐盛世,胡汉融合,万国来朝。故以周、秦、汉、唐为例,论述西安具有的包容精神,以斑窥豹,就教方家。 展开更多
关键词 西安 海纳百川 周秦汉唐 包容精神
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迈瑞BC-6800 Plus血小板相关参数参考区间的建立及验证
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作者 张宁 蒿花 孟欣 《海南医学》 CAS 2024年第13期1895-1900,共6页
目的建立并验证西安地区血小板相关参数血小板计数(PLT)、血小板体积分布宽度标准差(PDW-SD)、平均血小板体积(MPV)、血小板压积(PCT)、大血小板比率(P-LCR)、大血小板数量(P-LCC)、血小板体积分布宽度(PDW)的参考区间。方法选择2022年... 目的建立并验证西安地区血小板相关参数血小板计数(PLT)、血小板体积分布宽度标准差(PDW-SD)、平均血小板体积(MPV)、血小板压积(PCT)、大血小板比率(P-LCR)、大血小板数量(P-LCC)、血小板体积分布宽度(PDW)的参考区间。方法选择2022年8月至2023年8月在西安交通大学第一附属医院主院区和东院区5153名健康体检成年人群,采用迈瑞Mindray BC-6800 Plus血细胞分析仪检测外周血液,依据《临床实验室如何确定和建立生物参考区间;批准指南》CLSL C28-A3,以非参数法建立PLT、PDW-SD、MPV、PCT、P-LCR、P-LCC、PDW的参考区间。结果健康成年人群男、女不同性别间的PLT、MPV、PCT、P-LCR、P-LCC、PDW比较差异均具有统计学意义(P<0.05),但PDW-SD比较差异无统计学意义(P>0.05);各年龄段PLT、PCT、P-LCC、PDW间比较差异均具有统计学意义(P<0.05),但MPV、PDW-SD、P-LCR各年龄段间比较差异均无统计学意义(P>0.05)。标准正态离差检验方法显示无需按照性别、年龄段分组建立参考区间。PLT、MPV、PCT、PDW-SD、P-LCR、P-LCC、PDW的参考区间分别为(148~324)×10^(9)/L、8.4~12.5 fL、0.159%~0.322%、8.8~17.5 fL、15.1%~43.6%、(35~96)×10^(9)/L、15.1~16.8。结论建立并验证西安地区血小板相关参数参考区间,合理选用PDW-SD对异常血小板的识别,对血小板参数的自动审核提供必要的数据支持。 展开更多
关键词 西安地区 血小板 血小板体积分布宽度 血细胞分析仪 参考区间
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基于耦合协调模型的人水和谐度评价
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作者 王成军 张斯晴 +2 位作者 冯涛 杜传甲 张炳林 《人民黄河》 CAS 北大核心 2024年第8期87-93,共7页
为了合理地定量评价人水关系,以西安市为例,在人水和谐概念的基础上,构建人水和谐评价指标体系,通过改进G1赋权法计算各指标权重;以水系统和人文系统综合发展水平为基础,采用耦合协调模型计算人水系统协调度,并通过障碍度模型识别人水... 为了合理地定量评价人水关系,以西安市为例,在人水和谐概念的基础上,构建人水和谐评价指标体系,通过改进G1赋权法计算各指标权重;以水系统和人文系统综合发展水平为基础,采用耦合协调模型计算人水系统协调度,并通过障碍度模型识别人水系统协调发展障碍因素;采用单指标量化—多指标综合—多准则集成评价方法,先计算出水系统健康度和人文系统发展度,再与人水系统协调度集成,最终得到西安市2012—2021年人水和谐评价结果。结果表明:西安市人水协调度逐渐提高,各年份各指标对人水系统协调发展的阻碍程度清晰可见,人水和谐从较不和谐提升至和谐等级;该方法评价结果与实际相符,具有良好适用性,障碍因素的识别对人水关系进一步和谐有一定启发性。 展开更多
关键词 人水和谐 耦合协调模型 障碍度模型 西安市
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银西高铁黄土含水层隧道群井降水模拟研究
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作者 张晓宇 赵晓彦 宋浩 《铁道工程学报》 EI CSCD 北大核心 2024年第4期24-29,34,共7页
研究目的:银西高铁上阁村隧道穿越董志塬黄土含水层施工中出现的渗涌水,受地下水渗流影响,引起了洞身黄土含水率增加、围岩自稳性变差等问题。为解决上阁村富水黄土隧道施工难题,论文首先分析了上阁村隧道黄土含水层分布特征,其次介绍... 研究目的:银西高铁上阁村隧道穿越董志塬黄土含水层施工中出现的渗涌水,受地下水渗流影响,引起了洞身黄土含水率增加、围岩自稳性变差等问题。为解决上阁村富水黄土隧道施工难题,论文首先分析了上阁村隧道黄土含水层分布特征,其次介绍了地表降水施工辅助措施及其效果,最后应用MIDAS/GTS建立隧道工程群井降水模型,实现了不同流量以及渗透系数工况下的隧道开挖渗流模拟计算。研究结论:(1)上阁村隧道长大段落通过软塑黄土含水层,通过地表降水梳干隧道洞身范围内地下水,提高了隧道洞身黄土围岩稳定性,确保了隧道施工的安全和进度;(2)不同单井流量(80 m^(3)/d、90 m^(3)/d、100 m^(3)/d)的群井数值模拟结果表明,地下水位降深在短时间内达到了设计要求,验证了降水设计参数及效果;(3)本研究可为黄土等低渗透岩体富水隧道工程施工处置及设计提供依据。 展开更多
关键词 银西高铁 黄土隧道 含水层 群井降水 渗流模拟
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意义体验下的西安红色革命文化互动装置设计研究
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作者 王毅 龚伯瑞 胡瑞男 《设计》 2024年第5期24-27,共4页
体验经济时代下,通过文化意义体验创新,使受众在与互动装置互动过程获得情感以及精神层面的意义体验,从而增加文化的认同感。文章分析了文化互动装置与体验设计相关理论以及现状,结合“文化三层次”理论、符号学相关理论,探索了基于意... 体验经济时代下,通过文化意义体验创新,使受众在与互动装置互动过程获得情感以及精神层面的意义体验,从而增加文化的认同感。文章分析了文化互动装置与体验设计相关理论以及现状,结合“文化三层次”理论、符号学相关理论,探索了基于意义体验的文化互动装置设计转化方法。通过具体设计实践验证该方法的有效性。基于意义体验的西安红色革命文化互动装置设计研究是以体验设计以及符号学视角来实现文化传播与传承的桥梁,通过文化内涵的挖掘与创意设计转译,为西安红色革命文化的传承提供了新的方向。 展开更多
关键词 互动装置 体验设计 意义体验 设计转译 西安红色革命文化
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文旅视域下的西安新锐青年时装周发展研究
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作者 王田薇 刘欣怡 《服装设计师》 2024年第5期109-112,共4页
文章聚焦于服饰文化传播项目“西安新锐青年时装周”,以文旅视域为切入点,对该项目的意义与潜在发展空间进行分析;结合2023年“西安新锐青年时装周”院校板块“无界——西安美术学院服装系本科毕业作品展”与城市名片大唐不夜城项目的... 文章聚焦于服饰文化传播项目“西安新锐青年时装周”,以文旅视域为切入点,对该项目的意义与潜在发展空间进行分析;结合2023年“西安新锐青年时装周”院校板块“无界——西安美术学院服装系本科毕业作品展”与城市名片大唐不夜城项目的落地执行,进一步论述了当下该服饰文化传播与文旅项目的发展,力求在促进院校培养新锐时尚文化与城市形象文旅项目发展的同时,为当今文旅与服饰文化的进一步融合提供一定思路。 展开更多
关键词 西安新锐青年时装周 文旅视域 服饰文化传播
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第十四届全运会大气污染物减排措施对西安市气溶胶中水溶性离子和含碳组分的影响 被引量:1
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作者 沈利娟 王红磊 +4 位作者 赵天良 施双双 武自豪 可玥 刘焕武 《地球科学与环境学报》 CAS 北大核心 2024年第1期38-53,共16页
人为源密集的城市是空气污染影响的主要区域,厘清城市地区排放源的变化与大气污染物浓度之间的影响作用机制,有助于协调我国大气污染防控与城市社会经济发展之间的关系。为研究第十四届全运会期间大气污染物减排措施对西安市大气污染物(... 人为源密集的城市是空气污染影响的主要区域,厘清城市地区排放源的变化与大气污染物浓度之间的影响作用机制,有助于协调我国大气污染防控与城市社会经济发展之间的关系。为研究第十四届全运会期间大气污染物减排措施对西安市大气污染物(PM_(2.5)、PM_(10)、SO_(2)、NO_(2)、O_(3)和CO)的影响,于2021年8月6日至10月1日使用在线监测仪器观测了环境六要素、气象要素和PM_(2.5)中的气溶胶化学组分(有机碳、元素碳和水溶性离子)。结果表明:大气污染物减排措施对主要污染物O_(3)和PM_(2.5)浓度日变化的影响不同,主要由温度对光化学过程的影响和扩散条件差异导致。O_(3)在减排措施实施期间晴天峰值浓度更高、持续时间更长、浓度变化更迅速。PM_(2.5)在减排措施实施前晴天白天的峰值浓度较高,并在减排措施实施期间晴天夜间的峰值浓度较高。大气污染物减排措施对PM_(2.5)中化学组分的影响不同,尤其是对有机碳的组成影响较大。与减排措施实施前晴天相比,减排措施实施期间晴天NO_(3)^(-)、SO_(4)^(2-)、NH_(4)^(+)、Cl^(-)、Ca^(2+)、Na^(+)和NO_(2)^(-)浓度降低了17.9%~71.8%,K^(+)、Mg^(2+)和元素碳浓度增加了1.9%~13.6%,有机碳浓度仅降低了1.0%,但是一次有机碳浓度增加了13.6%,二次有机碳浓度降低了4.7%。NO_(3)^(-)/SO_(4)^(2-)值在减排措施实施期间晴天(0.53)远低于减排措施实施前晴天(1.66),表明减排措施实施期间交通源的贡献显著降低。降雨对NO_(3)^(-)和NH_(4)^(+)的清除较弱,反而会增加其浓度,但对K^(+)、Mg^(2+)、Ca^(2+)和Na+的清除作用较强。NO_(3)^(-)、SO_(4)^(2-)和NH_(4)^(+)在减排措施实施前后均是水溶性离子最重要的组成,在水溶性离子中的占比为90.8%(减排措施实施前的晴天)~95.8%(减排措施实施期间的雨天)。二次有机碳是有机碳的主要组成,占比为75.5%(减排措施实施期间的雨天)~79.9%(减排措施实施前的晴天)。不同阶段的水溶性离子和含碳气溶胶浓度日变化特征不同。NO_(3)^(-)、SO_(4)^(2-)和NH_(4)^(+)浓度晴天的日变化为单峰型分布,雨天为多峰型分布。 展开更多
关键词 水溶性离子 有机碳 元素碳 日变化 PM_(2.5) 臭氧 第十四届全运会 西安
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西安都市圈生态系统服务价值与人类活动强度的时空关系 被引量:1
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作者 朱琳娜 赵牡丹 +2 位作者 李云绯 樊艺 王建 《生态与农村环境学报》 CAS CSCD 北大核心 2024年第3期325-334,共10页
人类活动是影响生态系统服务价值(ecosystem service value,ESV)变化的重要原因之一,对两者时空关系的研究有助于生态环境与社会经济协调发展。以西安都市圈为研究对象,基于1990、2000、2010和2018年4期土地利用数据,在2 km×2 km... 人类活动是影响生态系统服务价值(ecosystem service value,ESV)变化的重要原因之一,对两者时空关系的研究有助于生态环境与社会经济协调发展。以西安都市圈为研究对象,基于1990、2000、2010和2018年4期土地利用数据,在2 km×2 km格网尺度下构建ESV评估模型、ESV流向损益模型、人类活动强度(human activity intensity,HAI)指数评估模型和双变量空间自相关模型,探讨ESV与人类活动强度的时空关系。结果表明:(1)1990—2018年间,西安都市圈ESV在时间尺度上呈持续下降趋势,近30年间共降低12.8亿元;在空间尺度上呈现以西安主城区为中心向外围递增的分布格局;(2)ESV增益主要源于耕地转为林地、水域和草地;ESV亏损主要源于耕地、建设用地的转入以及水域的转出;(3)人类活动强度整体呈现以西安主城区为中心向南北递减的空间分布格局,高影响区集中分布在西安主城区及其周边地区,低影响区分布于研究区南北两端;(4)ESV与人类活动强度呈负相关关系,两者聚类关系以低-高和高-低聚集方式为主,低-高和高-低聚集区域显著性水平高。期望通过对ESV与人类活动强度的空间关系分析为区域可持续发展提供理论支持。 展开更多
关键词 生态系统服务价值 人类活动强度 格网尺度 双变量空间自相关性 西安都市圈
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陕西西安相家巷遗址H3发掘简报
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作者 韩保全(领队) 王凤娥(绘图) +4 位作者 王文渊(摄影) 张翔宇 温晓星 柴怡 韩国河 《文博》 北大核心 2024年第2期3-23,F0002,I0001,共23页
西安相家巷遗址出土秦封泥数量庞大,较多封泥出土于灰坑中,内容涵盖中央职官与地方职官类,其中H3中出土封泥数量颇丰,类别多样,这批封泥的整理研究为学界研究“三公九卿”制提供了丰富可靠的实物资料,亦为研究秦汉职官体系、政区地理、... 西安相家巷遗址出土秦封泥数量庞大,较多封泥出土于灰坑中,内容涵盖中央职官与地方职官类,其中H3中出土封泥数量颇丰,类别多样,这批封泥的整理研究为学界研究“三公九卿”制提供了丰富可靠的实物资料,亦为研究秦汉职官体系、政区地理、封缄制度、文字演化、书法艺术提供了可靠的一手材料。 展开更多
关键词 西安市 相家巷遗址 H3 秦封泥
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