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“借势”嵌入与“有为”补能:社区环境线索对低龄老年人参与城市基层治理共同体建设的影响路径

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人口与发展 2024年第1期30卷 83-95,142页

作者：何继新夏五洲高雪宁天津城建大学经济与管理学院天津300384

基于线索利用理论建构的社区制度-文化-设施-参与环境线索分析框架,通过Ologit-ISM模型实证分析社区环境线索对低龄老年人参与城市基层治理共同体建设的影响路径,探究各个显著影响因素之间的逻辑层级关系。研究表明,近69%的低龄老年人... 详细信息

基于线索利用理论建构的社区制度-文化-设施-参与环境线索分析框架,通过Ologit-ISM模型实证分析社区环境线索对低龄老年人参与城市基层治理共同体建设的影响路径,探究各个显著影响因素之间的逻辑层级关系。研究表明,近69%的低龄老年人愿意参与到城市基层治理共同体建设,男性低龄老年人的参与意愿明显高于女性低龄老年人;社区制度环境线索、社区文化环境线索、社区设施环境线索、社区参与环境线索是影响低龄老年人参与城市基层治理共同体建设的主要因素,年龄、受教育程度、管理透明度、老年人教育培训是深层因素,并通过健康状况、社区服务平台、社区设施活动布局、居民自主性、参与渠道等第一层中间层因素,引致到参与成效、社区共同体意识、子女数目等第二层中间层因素,形成链式中介作用,进而作用到共同体结构、参与内容、社区文化、激励机制等表层因素,最终影响到低龄老年人参与城市基层治理共同体建设。

关键词：城市基层治理共同体参与意愿 Ologit-ISM模型线索利用理论

Warming in Arctic intermediate and deep waters around Chukchi Plateau and its adjacent regions in 1999

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Science china Earth Sciences 2005年第8期48卷 1312-1320页

作者： ZHAO Jinping1, GAO Guoping2.& JIAO Yutian1 1. first Institute of Oceanography, State Oceanic Administration, Qingdao 2.6061, china 2. Ocean University of china, Qingdao 2.6003, china first Institute of Oceanography State Oceanic Administration Qingdao China Ocean University of china Qingdao China

Based on the data measured during Arctic scientific expedition of china in 1999, the characteristics of temperature and salinity distributions around the Chukchi Plateau and its ad-jacent regions have been studied. It was found that the intermediate water with temperature higher than 0.5℃ existed in all parts of a 640 km section with a maximum temperature of 0.85℃ indicating a strong signal of the warming in Arctic Intermediate Water in 1999. Two important phenomena are described in this paper. first, the temperature of warm water was horizontally nonuniform. In the area of Chukchi Plateau, the temperature was higher, the layer of warm water was thicker and the depth of the warm water core was shallower than those in the area of con-tinental slope. The horizontal nonuniformity of the temperature distribution of warming water im-plies that the upward heat flux should also be nonuniform, thus exerting different effects on sea ice thickness, ice extent, and air-sea heat exchange. The mechanism to generate higher tem-perature in the plateau region was the bypassing of current around the plateau area caused by the special local topography, which restricted water exchange across the plateau and conserved heat in the water body. Second, the deep water down to 1400 m was also warming with a tem-perature increase of 0.2.. The warming in deep water reflects the occurrence of complicated heat redistribution processes in the intermediate water, which altered the thermal structure in the upper 1400 m. The warming data embody the obvious impact of global climate change on the Arctic Ocean and further studies are wanted.

关键词： Chukchi Plateau, Arctic Ocean, warming in intermediate water, warming in deep water.

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高声强双层穿孔结构的吸声计算

同济大学学报（自然科学版） 2024年第9期52卷 1464-1468页

作者：俞悟周贺银芝姜在秀孙浩钧同济大学物理科学与工程学院上海200092 上海市地面交通工具空气动力与热环境模拟重点实验室上海201804 同济大学汽车学院上海201804

对高声强下不同的穿孔结构非线性声阻抗模型进行比较,分析入射声压对穿孔吸声结构声阻抗的影响,并提出双层穿孔结构的改进传递矩阵法。不同声阻抗模型的实验和计算结果表明,入射声压级小于140 dB时,Park模型和Maa模型的计算结果与实验... 详细信息

对高声强下不同的穿孔结构非线性声阻抗模型进行比较,分析入射声压对穿孔吸声结构声阻抗的影响,并提出双层穿孔结构的改进传递矩阵法。不同声阻抗模型的实验和计算结果表明,入射声压级小于140 dB时,Park模型和Maa模型的计算结果与实验数据吻合良好;入射声压级为140~150 dB时,Laly模型的计算结果更接近实验结果。对于高声强下的双层及多层穿孔结构,在所提出的改进传递矩阵法中,根据传递矩阵计算得到各层板表面声压级,每层穿孔的声阻抗根据声压级和穿孔参数进行计算,进而得到总声阻抗。结果表明,入射声压级为12.~150 dB时,双层穿孔结构的改进传递矩阵法计算结果与实验数据吻合良好。

关键词：降噪吸声双层穿孔结构高声强非线性声阻抗

ADVECTION AND DIFFUSION OF POISONOUS GAS CONTAMINANT RELEASED FROM BOTTOM SLUDGE IN OPEN CHANNEL

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Journal of Hydrodynamics 2004年第1期16卷 80-83页

作者： wuzhou-hu DepartmentofEnvironmentEngineering QingdaoInstituteofArchitectureandEngineeringQingdao266033China

In some cases, poisonous contaminants may be released from bottom sludge inopen channels. The equation of advection and diffusion for the related problem was analyzed in thispaper. The conditions for the definite solution to the equation were given. The analytic solution ofpoisonous gas concentration distribution was worked out. The reasonableness of this solution wasdiscussed. The result is also of significance for other similar problems.

关键词： bottom sludge poisonous gas contaminant concentration distribution

硬质聚氨酯泡沫/EG/MPP复合材料的制备及阻燃性能

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塑料工业 2024年第5期52卷 147-152页

作者：杨武洲陈婷伍强唐刚马鞍山市消防救援支队安徽马鞍山243000 安徽工业大学建筑工程学院安徽马鞍山243002

将三聚氰胺聚磷酸盐(MPP)与可膨胀石墨(EG)进行复配,并采用一步法全水发泡法制备了硬质聚氨酯泡沫/可膨胀石墨/三聚氰胺聚磷酸盐(RPUF/EG/MPP)复合材料。在此基础上,采用热重分析(TG)、阻燃测试、微型量热(MCC)、扫描电镜(SEM)系统研究R... 详细信息

将三聚氰胺聚磷酸盐(MPP)与可膨胀石墨(EG)进行复配,并采用一步法全水发泡法制备了硬质聚氨酯泡沫/可膨胀石墨/三聚氰胺聚磷酸盐(RPUF/EG/MPP)复合材料。在此基础上,采用热重分析(TG)、阻燃测试、微型量热(MCC)、扫描电镜(SEM)系统研究RPUF/EG/MPP复合材料的热稳定性、阻燃性、燃烧特性和炭渣微观形貌。研究表明,EG和MPP的加入可以明显提高RPUF/EG/MPP复合材料的热稳定性,40.6份MPP和2..3份EG的加入使得RPUF-2.800℃时,残炭率高达31.7%。阻燃测试表明,MPP和EG之间存在协效阻燃作用,其最大极限氧指数可达2..9%。微型量热测试表明,MPP和EG的加入可以有效降低RPUF复合材料燃烧过程中的热释放,提升其火灾安全性能。

关键词：硬质聚氨酯泡沫可膨胀石墨三聚氰胺聚磷酸盐复合材料协效阻燃

Effect of Dy on Structure and Magnetic Properties of Dy_xFe_(60.5-x)Pt_(39.5) Alloys

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 135-137页

作者：左卫群 Department of Information of Materials Science and Engineering Guilin University of Electronic Technology

Effects of the content of Dy on structure and magnetic properties of DyxFe60.5-xPt39.5 alloys（x = 0, 0.5, 1.0, 1.5） were investigated. The results of XRD analysis proved that the phase-transitional temperature of DyxFe60.5-xPt39.5 alloys from disordered face-centered-cubic structure to ordered face-centered-tetragonal cubic structure decreases with the increase of the content of Dy（x）. Suitable content of Dy can improve the exchange coupling between soft magnetic phase and hard magnetic phase by refining grain size, while the remanence ratio and coercivity of the Fe60.5Pt39.5 alloy can be significantly improved by a small replacement of Fe by Dy, good magnetic properties were obtained in Dy0.5Fe60.0Pt39.5 alloys.

关键词： phase transformation degree of order grain size exchange coupling

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高速铁路声屏障宽频穿孔吸声降噪结构

同济大学学报（自然科学版） 2024年第9期52卷 1469-1473页

作者：盛峰姜在秀贺银芝曾小清邓波安雪晖俞悟周清华大学土木水利学院北京100084 中电建路桥集团有限公司北京100070 同济大学物理科学与工程学院上海200092 上海市地面交通工具空气动力与热环境模拟重点实验室上海201804 同济大学汽车学院上海201804 同济大学道路与交通工程教育部重点实验室上海201804

采用传递矩阵法对高铁声屏障的多层微穿孔结构的吸声进行计算。对给定空腔深度,适当增加具有不同声阻抗的微穿孔板可改善吸声性能。经遗传算法得到具有优化参数的4层和5层微穿孔结构可显著拓宽吸声频带,提高整个频带的吸声系数,在2.0~31... 详细信息

采用传递矩阵法对高铁声屏障的多层微穿孔结构的吸声进行计算。对给定空腔深度,适当增加具有不同声阻抗的微穿孔板可改善吸声性能。经遗传算法得到具有优化参数的4层和5层微穿孔结构可显著拓宽吸声频带,提高整个频带的吸声系数,在2.0~3150 Hz频率范围内的平均吸声系数分别为0.70和0.80,吸声频带涵盖2.0~350 km⋅h^(-1)高速铁路主要噪声频率范围。5层结构在400~4000 Hz频率范围内吸声系数可达0.8。

关键词：高速铁路噪声声屏障微穿孔

Discovery of seismites in Upper Sinian stratiform lead-zinc deposits in Dadu River valley, Sichuan, china: Implication for ore genesis

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Science china Earth Sciences 2006年第11期49卷 1135-1146页

作者： LIN Fangcheng1,2.& PAN Guitang2.1. Geoscience College, Chengdu University of Technology, Chengdu 610059, china 2. Chengdu Institute of Geology and Mineral Resources, Chengdu 610082. china Geoscience College Chengdu University of Technology Chengdu China Chengdu Institute of Geology and Mineral Resources Chengdu China

A number of lead-zinc sulphide deposits have been discovered in recent years in dolo- mitic rocks of the Upper Sinian Dengying Formation in the Dadu River valley region, Sichuan Province, china. The lead-zinc mineralization is closely associated with a black siliceous exhalite that has been traced over 50 km of strike. This makes Dadu River valley the most extensive stratiform non-ferrous sulphide horizon having been discovered to date in china. In a previous study by the {2. author (LIN), these deposits were recognised as belonging to the broad spectrum of lead-zinc sedimentary exhala- tive (SEDEX) deposits. In this paper, seismites and seismogenetic structures occurring in close association with the Dadu River valley mineralized zone are described. The close spatial and temporal relationship between the seismites and mineralization provides strong evidence for the hypothesis that the lead-zinc SEDEX deposits formed in direct response to earthquake activities around the Sinian-Cambrian boundary. The earthquakes are postulated to be an effective dynamic mechanism for triggering the upward migration of deep circulating ore fluids along synsedimentary growth faults and their exhalation onto the sea-floor to form the extensive deposits of stratiform lead-zinc sulphide ore.

关键词： seismites, earthquake, lead-zinc deposit, hydrothermal exhalation, Upper Sinian Dengying Age.

The GPS-gravimetry boundary value problem

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Science china Earth Sciences 2005年第3期48卷 398-405页

作者： YU Jinhai1,2.& ZHANG Chuanding2.1. Institute of Geodesy and Geophysics of Chinese Academy of Sciences, Wuhan 430077, china 2. Zhengzhou Information Engineering University, Zhengzhou 450052. china Institute of Geodesy and Geophysics of Chinese Academy of Sciences Wuhan China Zhengzhou Information Engineering University Zhengzhou China

How to determine the earth’s external gravity field with the accuracy of O(T2. by making use of GPS data and gravity values measured on the earth’s surface is dealt with in this paper. There are two main steps: to extend these measured values on the earth’s surface onto the reference ellipsoid at first and then to seek for the integral solution of the external Neumann problem outside the ellipsoid. In addition, the corresponding judging criteria of accuracy to solve the GPS-gravity boundary value problem are established. The integral solution given in the paper not only contains all frequency-spectral information of the gravity field with the accuracy of O(T 2., but is also easily computed. In fact, the solution has great significance for both theory and prac- tice.

关键词： Neumann boundary value problem, integral solution, gravity disturbance.