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产业园区资产证券化的违约风险——基于北大科技园的案例研究

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管理案例研究与评论 2024年第2期17卷 297-319页

作者：张琳张妞黄意明大连理工大学经济管理学院大连116024

在中国大力发展实体经济的背景下,产业园区的发展也备受关注。产业园区资产证券化产品于2018年呈现出爆发式增长态势,但该产品目前尚处于探索阶段,面临的违约风险较大,需要不断完善。为此,选取中国产业园区资产证券化的首单违约产品—... 详细信息

在中国大力发展实体经济的背景下,产业园区的发展也备受关注。产业园区资产证券化产品于2018年呈现出爆发式增长态势,但该产品目前尚处于探索阶段,面临的违约风险较大,需要不断完善。为此,选取中国产业园区资产证券化的首单违约产品——北大科技园商业地产抵押贷款支持票据作为研究对象,基于北大科技园资产证券化产品原始浅层的风险识别和风险应对设计,首先,对其进行了深度的风险识别,并通过KMV模型等进行风险评估量化分析;其次,提出完备的风险应对方法;最后,通过风险调整手段评估调整现存风险、评估识别未知风险,进而构建完整的风险管理闭环机制。以期为其他企业规避融资风险提供有益借鉴,进而让金融更好地服务于实体经济,推进实体经济发展行稳致远。

关键词：产业园区资产证券化风险管理

关于房屋建筑工程中绿色节能施工技术的运用分析

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工程与建设 2024年第3期38卷 688-690页

作者：牛章红山西昊圣建设工程项目管理有限责任公司山西太原041000

我国建筑业发展迅猛,在城市建设中,房屋建筑工程施工项目越来越多,规模越来越大,结构也越来越复杂.而其发展过程中所产生的资源浪费、环境污染等问题也日益引起人们的重视.要解决这个问题,就必须加速节能环保技术的运用,把绿色节能理念... 详细信息

我国建筑业发展迅猛,在城市建设中,房屋建筑工程施工项目越来越多,规模越来越大,结构也越来越复杂.而其发展过程中所产生的资源浪费、环境污染等问题也日益引起人们的重视.要解决这个问题,就必须加速节能环保技术的运用,把绿色节能理念融入工程施工之中.绿色节能施工就是要采用绿色的材料和新能源,强化建设项目的技术创新,在设计、选材、施工等各个环节运用科学、先进的施工工艺,在确保建筑的安全性、把质量放在第一位的前提下,尽量降低能耗、减轻施工对周围环境的影响.将绿色可持续发展作为各个行业发展的方向,能够更好地推动我国生态环境与市场经济的协调发展.本文对我国房屋建筑工程施工项目进行了全面、系统的研究,以期推动我国房屋建筑工程施工项目的可持续发展.

关键词：房屋建筑工程绿色节能施工技术应用

BASIC HYDRODYNAMICS CHARACTERISTICS OF CAVITY SPIRAL FLOW IN A LARGE SIZE LEVEL PIPE

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Journal of Hydrodynamics 2005年第4期17卷 503-513页

作者： niu Zheng-ming zhang Ming-yuan School of Energy and Power Engineering Xi＇an Jiaotong University Xi＇an 710048 China

Based on the observation of a model test and in combination with some theoretical analysis, the researches of some basic hydrodynamics characteristics of cavity spiral flow in a large size level pipe with a shaft-inlet is presented in the paper, which include the basic flow pattern, formation condition of the cavity spiral flow, discharge Q, cavity diameter d0, wall pressure coefficient Cpw, velocity distribution, total energy dissipation rate η etc. The results show that the basic flow patterns can be divided into three zones according to the variations in amount of ventilation Ф, cavity diameter d0 and gas pressure p0 within cavity spiral flow when the upstream and downstream water level changes and that the basic hydrodynamics characteristics change with the flow pattern and have the different behaviour.

关键词： hydrodynamics characteristics flow pattern zoning change cavity spiral flow large size level pipe

Mercury in leaf litter in typical suburban and urban broadleaf forests in China

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Journal of Environmental Sciences 2011年第12期23卷 2042-2048页

作者： Zhenchuan niu Xiaoshan zhang zhangwei Wang Zhijia Ci Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

To study the role of leaf litter in the mercury （Hg） cycle in suburban broadleaf forests and the distribution of Hg in urban forests, we collected leaf litter and soil from suburban evergreen and deciduous broadleaf forests and from urban forests in Beijing. The Hg concentrations in leaf litter from the suburban forests varied from 8.3 to 205.0 ng/g, with an average （avg） of （49.7 ± 36.9） ng/g. The average Hg concentration in evergreen broadleaf forest leaf litter （50.8 ± 39.4） ng/g was higher than that in deciduous broadleaf forest leaf litter （25.8 ± 10.1） ng/g. The estimated Hg fluxes of leaf litter in suburban evergreen and deciduous broadleaf forests were 179.0 and 83.7 mg/（ha·yr）, respectively. The Hg concentration in organic horizons （O horizons）（（263.1 ± 237.2） ng/g） was higher than that in eluvial horizons （A horizons）（（83.9 ± 52.0） ng/g）. These results indicated that leaf litterfall plays an important role in transporting atmospheric mercury to soil in suburban forests. For urban forests in Beijing, the Hg concentrations in leaf litter ranged from 8.8–119.0 （avg 28.1 ± 16.6） ng/g, with higher concentrations at urban sites than at suburban sites for each tree. The Hg concentrations in surface soil in Beijing were 32.0–25300.0 ng/g and increased from suburban sites to urban sites, with the highest value from Jingshan （JS） Park at the centre of Beijing. Therefore, the distribution of Hg in Beijing urban forests appeared to be strongly influenced by anthropogenic activities.

关键词： mercury broadleaf forests leaf litter soil flux

Effect of Welding Paramenter on Joint Property of Aluminum Matrix Composite in Liquid-Phase-Impacting Diffusion Welding

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Journal of Materials Science & Technology 2003年第z1期19卷 195-198页

作者： Wei GUO Qingchang MENG Jitai niu Xinmei zhang The National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology1 Harbin 150001 China The National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology1 Harbin 150001 China The National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology1 Harbin 150001 China The National Key Laboratory of Metal Matrix Composite Shanghai Jiao Tong University Shanghai 200030 China The National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology1 Harbin 150001 China

In this paper, a new method for welding SiCp/101A was put forward. It is LPI (liquid-phase-impacting) diffusionwelding. Through LPI diffusion welding SiCp/101A aluminum, the effect of welding parameters on the weldedjoint property was investigated, and the optimal welding parameters were brought forward at the same time. Themicrostructure of joint was analyzed by means of optical-microscope, scanning electron microscope in order to studythe relationship between the macro-properties of joint and the microstructure. The results show that LPI diffusionwelding could be used for welding aluminum matrix composites SiCp/101A successfully.

关键词： Aluminum matrix composite, Liquid-phase-impacting diffusion welding, SiCp/101A

Experimental research on hydrophilic characteristics of natural soft rock at high stress state

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International Journal of Mining Science and Technology 2015年第3期25卷 489-495页

作者： Guo Hongyun Lei Xiangyang zhang Yumei Yang Guoxing niu zhang The Engineering Design Research Institute of Equipment of PLA Astronaut Center of China China Taiyuan Satellite Launch Center

In order to study features of rock–water interaction, a self-developed experimental system called Intelligent Testing System for Water Absorption in Deep Soft Rocks(ITSWADSR) was utilized to analyze the hydrophilic behaviors of natural soft rock at high stress state. Combining X-ray diffraction and mercury injection test, main influencing factors on hydrophilic characteristics were studied. According to the results, it could be concluded as the following:(1) the effective porosity, and the content of illite, illite/smectite formation(S = 5%) and kaolinite have positive correlation with the water absorption capacity of rock; meanwhile, the initial moisture content, fractal dimension of effective pores, illite/smectite formation(S = 30%) and chlorite present negative correlation;(2) among the positive factors, the ascending order is kaolinite, illite/smectite formation(S = 5%) and illite;(3) the descending order among the negative factors are chlorite, illite/smectite formation(S = 30%) and fractal dimension of the effective pores;(4) influence of effective porosity on the pressurized water absorbing capacity of rock is minimal, while it is maximal in the process of no pressurized water absorption.

关键词： Natural soft rock Water absorption tests X-ray diffraction Mercury injection test Hydrophilic characteristics

Light Trapping Effect in Wing Scales of Butterfly Papilio peranthus and Its Simulations

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Journal of Bionic Engineering 2013年第2期10卷 162-169页

作者： Zhiwu Han Shichao niu Lufeng zhang Zhenning Liu Luquan Ren Key Laboratory of Bionic Engineering (Ministry of Education China) Jilin University Changchun 130022 P. R. China

Broadband light trapping effect and arrays of sub-wavelength textured structures based on the butterfly wing scales are applicable to solar cells and stealth technologies. In this paper, the fine optical structures in wing scales of butterfly Papilio peranthus, exhibiting efficient light trapping effect, were carefully examined. First, the reflectivity was measured by reflectance spectrum. Field Emission Scanning Electronic Microscope （FESEM） and Transmission Electron Microscope （TEM） were used to observe the coupling morphologies and structures of the scales. Then, the optimized 3D model of the coupling structure was created combining Scanning Electron Microscope （SEM） and TEM data. Afterwards, the mechanism of the light trapping effect of these structures was analyzed by simulation and theoretical calculations. A multilayer nano-structure of chitin and air was found. These structures are effective in increasing optical path, resulting in that most of the incident light can be trapped and adsorbed within the structure at last. Furthermore, the simulated optical results are consistent with the experimental and calculated ones. This result reliably confirms that these structures induce an efficient light trapping effect. This work can be used as a reference for in-depth study on the fabrication of highly efficient bionic optical devices, such as solar cells, photo detectors, high-contrast, antiglare, and so forth.

关键词： butterfly wing scale light trapping structures biomimetic functional surfaces

Discovery of super-silicic and super-titanic garnets in garnet-pyroxenite in Zhaheba and its geological significance

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Chinese Science Bulletin 2008年第14期53卷 2186-2191页

作者： niu HeCai zhang HaiXiang SHAN Qiang YU XueYuan Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Super-silicic garnet which exists stably at more than 5 GPa is a typical ultra-high pressure mineral. The super-silicic garnet and super-titanic garnet were discovered for the first time in garnet-pyroxenite of early Paleozoic Zhaheba-Aermantai orogenic belt in north Xinjiang. Our study indicates that these su- per-silicic garnets as well as super-titanic garnets were formed at a depth of at least 300 km. Their host rock―― garnet-pyroxenite is one kind of ultra-pressure metamorphic rocks which is related to the ul- tra-deep subduction of the oceanic crust. Thus, the early Paleozoic Zhaheba-Aermantai orogenic belt is related to the ultra-deep subduction of the Paleo-Asian oceanic crust.

关键词：蛇纹石辉岩石榴石变质作用

集成X射线、TEM和STM的晶体学教学尝试

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大学化学 2024年第3期39卷 5-17页

作者：马宏伟张芳艾惠张妞彭绍春李晖北京理工大学分析测试中心北京122488 北京理工大学化学化工学院北京122488

以Si晶体为例,介绍了一种结合X-射线、电子显微学和扫描隧道显微技术进行晶体学教学的尝试。主要是从基本原理、实验技术、实验结果等方面建立不同方法之间的联系,也说明其区别。目的是使学生能依据基本的晶体学原理、概念和数据,理解... 详细信息

以Si晶体为例,介绍了一种结合X-射线、电子显微学和扫描隧道显微技术进行晶体学教学的尝试。主要是从基本原理、实验技术、实验结果等方面建立不同方法之间的联系,也说明其区别。目的是使学生能依据基本的晶体学原理、概念和数据,理解不同的晶体结构分析和表征方法提供的晶体学信息之间的区别和联系,达到融会贯通的效果。

关键词：晶体学教学 X-射线 TEM STM