隧道纵向抗震分析的反应加速度方法∗

为研究隧道纵向地震响应,首先将隧道结构的动力问题简化为地震变形场作用下的土?隧道拟静力相互作用问题,推导了土?隧道拟静力相互作用模型的反应加速度方法。针对规范提供的纵向位移模式,给出相应反应加速度方法的等效惯性力公式及模型边界条件,最终建立基于规范位移模式的隧道纵向反应加速度方法。在与整体式反应位移方法对比验证的基础上,开展不同场地条件及不同隧道埋深下的隧道纵向响应规律研究。数值模拟结果表明：(1)当场地条件和埋深相同时,隧道弯矩随场地水平位移的增加而增加,而剪力、扭矩具有相反的变化规律; (2)场地条件对隧道纵向响应的影响较大,场地越软,隧道剪力越小,而弯矩和扭矩越大;(3)在 50 m 覆盖土层厚度内,随隧道埋深的增加,隧道剪力、弯矩逐渐减小,而扭矩基本保持不变。     

利用新型电解槽回收废定影液中的银

采用新型辐射状电极电解槽设备进行了电解回收废定影液中银的工业试验,结果表明,银的回收率达99.6%,单位电耗为0.7kW·h/kgAg,电流效率达57.9%。同时,利用回收银后的废液处理含铬废水,出水中的六价铬和总铬都符合国家排放标准,达到了以废治废的目的。     

地下结构震害类型及机理研究

地下结构由于受到周围岩体或土体的约束 ,一直被认为具有良好的抗震性能。但是 ,随着地下结构数量的增多和地下结构震害的频繁出现 ,地下结构的震害问题日益受到世界各国地震工作者的高度重视 ,笔者通过对大量地下结构震害的分析研究 ,对地下结构震害进行了分类 ,并研究了震害的影响因素及机理 ,以期为地下结构的抗震设计提供科学依据和有益的参考。     

浅析职业服装的分类及设计

1 前言 职业服装是融标志性、功能性、时尚性、实用性及科学性于一体并具有行业特点和职业特征．能满足职业功能，体现团队精神和服饰文化的标志性服装。     

Calculation of clothing insulation by serial and parallel methods: effects on clothing choice by IREQ and thermal responses in the cold.

Cold protective clothing was studied in 2 European Union projects. The objectives were (a) to examine different insulation calculation methods as measured on a manikin (serial or parallel), for the prediction of cold stress (IREQ); (b) to consider the effects of cold protective clothing on metabolic rate; (c) to evaluate the movement and wind correction of clothing insulation values. Tests were carried out on 8 subjects. The results showed the possibility of incorporating the effect of increases in metabolic rate values due to thick cold protective clothing into the IREQ model. Using the higher thermal insulation value from the serial method in the IREQ prediction, would lead to unacceptable cooling of the users. Thus, only the parallel insulation calculation method in EN 342:2004 should be used. The wind and motion correction equation (No. 2) gave realistic values for total resultant insulation; dynamic testing according to EN 342:2004 may be omitted.     

City ventilation of Hong Kong at no-wind conditions

We hypothesize that city ventilation due to both thermally-driven mountain slope flows and building surface flows is important in removing ambient airborne pollutants in the high-rise dense city Hong Kong at no-wind conditions. Both spatial and temporal urban surface temperature profiles are an important boundary condition for studying city ventilation by thermal buoyancy. Field measurements were carried out to investigate the diurnal thermal behavior of urban surfaces (mountain slopes, and building exterior walls and roofs) in Hong Kong by using the infrared thermography. The maximum urban surface temperature was measured in the early noon hours (14:00–15:00 h) and the minimum temperature was observed just before sunrise (5:00 h). The vertical surface temperature of the building exterior wall was found to increase with height at daytime and the opposite occurred at nighttime. The solar radiation and the physical properties of the various urban surfaces were found to be important factors affecting the surface thermal behaviors. The temperature difference between the measured maximum and minimum surface temperatures of the four selected exterior walls can be at the highest of 16.7 °C in the early afternoon hours (15:00 h). Based on the measured surface temperatures, the ventilation rate due to thermal buoyancy-induced wall surface flows of buildings and mountain slope winds were estimated through an integral analysis of the natural convection flow over a flat surface. At no-wind conditions, the total air change rate by the building wall flows (2–4 ACH) was found to be 2–4 times greater than that by the slope flows due to mountain surface (1 ACH) due to larger building exterior surface areas and temperature differences with surrounding air. The results provide useful insights into the ventilation of a high-rise dense city at no-wind conditions.     

Protected area governance in Sweden: new modes of governance or business as usual?

This paper explores whether ambitions to open up the traditional Swedish model of top-down conservation methods to local influences are indicative of an actual transition in governance of Swedish national park policy (NPP), and examines whether such a shift entails an increase in local influence over local interests and needs. Methodologically, we analyse a combination of governance types and incorporate theoretical definitions of power and accountability. The establishment of new governance arrangements – where power is shared, interactions promoted and accountability is directed downwards – indicates that Sweden's NPP is undergoing a change in its mode of governance. This change also seems to include ceding some influence to local interests, and the possibility of combining conservation with the utilisation of certain natural resources. The results of our research also provide valuable insights into when the establishment of shared-governance arrangements are likely to succeed; in short, this seems more likely when there are established sectors sited in a robust legal framework and where strong international commitments potentially play a role. In conclusion, we contend that when seeking diversified governance arrangements it is not enough simply to take local practices and customs into consideration – they have to be strengthened.     

Semi-Coke-Supported Mixed Metal Oxides for Hydrogen Sulfide Removal at High Temperatures

To improve the desulfurization efficiency of sorbents at low cost, modified semi-coke was used as the substrate for mixed metal oxides (ZFM; oxides of zinc [Zn], iron [Fe], and manganese [Mn]) in hot gas desulfurization. Performance of the prepared ZFM/modified semi-coke (MS) sorbents were evaluated in a fixed-bed reactor in the temperature range 400-550°C. Results showed that the molar ratio of Mn to Zn, effect of the substrate, the calcination temperature, and the sulfidation temperature influenced the performance of the sorbents. Optimum conditions for the preparation of the ZFM/MS sorbents were molar ratio of Mn(NO(3))(2)·6H(2)O, Zn(NO(3))(2), and Fe(NO(3))(3), 0.6:1:2; mass ratio of ZFM0.6 to modified semi-coke support, 1:1; and calcination temperature, 600°C. The ZFM0.6/MS sorbent thus prepared exhibited the best sorption sulfur capacity of 27.46% at 450°C.     

城市燃气管道地震安全控制演示系统

介绍了一种用于展示城市燃气管道地震安全控制系统工作机理和控制效果的演示系统。对演示系统地震阀门的原理和性能作了阐述,对演示系统的组成、工作原理和效果做了较为详细的介绍。该系统可用于科普场馆或相关单位介绍城市燃气管道地震紧急处置的原理,系统已在唐山市地震博物馆安装应用。