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1.
Fire spread and growth on real‐scale four cushion mock‐ups of residential upholstered furniture (RUF) were investigated with the goal of identifying whether changes in five classes of materials (barrier, flexible polyurethane foam, polyester fiber wrap, upholstery fabric, and sewing thread), referred to as factors, resulted in statistically significant changes in burning behavior. A fractional factorial experimental design plus practical considerations yielded a test matrix with 20 material combinations. Experiments were repeated a minimum of two times. Measurements included fire spread rates derived from video recordings and heat release rates (HRRs). A total of 13 experimental parameters (3 based on the videos and 10 on the HRR results), referred to as responses, characterized the measurements. Statistical analyses based on Main Effects Plots (main effects) and Block Plots (main effects and factor interactions) were used. The results showed that three of the factors resulted in statistically significant effects on varying numbers of the 13 responses. The Barrier and Fabric factors had the strongest main effects with roughly comparable magnitudes. Foam was statistically significant for fewer of the responses and its overall strength was weaker than for Barrier and Fabric. No statistically significant main effects were identified for Wrap or Thread. Multiple two‐term interactions between factors were identified as being statistically significant. The Barrier*Fabric interaction resulted in the highest number of and strongest statistically significant effects. The existence of two‐term interactions means that it will be necessary to consider their effects in approaches designed to predict the burning behavior of RUF.  相似文献   
2.
针对区域地面沉降监测点数量有限、分布不均的情况,一般采用空间插值的手段建立表面拟合模型来解决。基于分形插值,采用随机选择迭代函数的思想对传统的趋势面拟合法作出改进,改进后拟合优度系数提高0.03,达到0.995,且改进前后的拟合结果符合显著性检验的要求。实验结果表明:改进前后趋势面拟合法拟合结果满足地面沉降监测的精度要求,改进后方法的拟合优度更高,对现实地面沉降量变化的描绘更加真实,可为沉降灾害评价工作提供更准确的依据。  相似文献   
3.
Understanding the sources and composition of organic aerosol (OA) in indoor environments requires rapid measurements, since many emissions and processes have short timescales. However, real-time molecular-level OA measurements have not been reported indoors. Here, we present quantitative measurements, at a time resolution of five seconds, of molecular ions corresponding to diverse aerosol-phase species, by applying extractive electrospray ionization mass spectrometry (EESI-MS) to indoor air analysis for the first time, as part of the highly instrumented HOMEChem field study. We demonstrate how the complex spectra of EESI-MS are screened in order to extract chemical information and investigate the possibility of interference from gas-phase semivolatile species. During experiments that simulated the Thanksgiving US holiday meal preparation, EESI-MS quantified multiple species, including fatty acids, carbohydrates, siloxanes, and phthalates. Intercomparisons with Aerosol Mass Spectrometer (AMS) and Scanning Mobility Particle Sizer suggest that EESI-MS quantified a large fraction of OA. Comparisons with FIGAERO-CIMS shows similar signal levels and good correlation, with a range of 100 for the relative sensitivities. Comparisons with SV-TAG for phthalates and with SV-TAG and AMS for total siloxanes also show strong correlation. EESI-MS observations can be used with gas-phase measurements to identify co-emitted gas- and aerosol-phase species, and this is demonstrated using complementary gas-phase PTR-MS observations.  相似文献   
4.
黄津 《山西建筑》2006,32(18):149-150
分析了某小区边坡渗水的原因,结合实际情况,介绍了边坡渗水的治理措施,并对渗水进行了收集综合利用,消除了边坡滑坡的安全隐患,取得了较好的社会效益和经济效益。  相似文献   
5.
现代住区规划的几点思考   总被引:2,自引:0,他引:2  
通过对居住区规划中住区交通组织、环境建设,以及住宅配套现实处理方法的分析,指出现代住区的规划要根据当地实际情况,因地制宜组织住区交通网络,合理整合住宅内外环境,适度超前建设配套设施。  相似文献   
6.
介绍了煤矿塌陷坑的治理途径和复垦的意义。  相似文献   
7.
海河流域河道外生态需水研究   总被引:7,自引:0,他引:7  
水土流失是海河流域较为突出的生态环境问题之一。经对比研究发现,植被覆盖度的变化会通过影响洪充量,土壤侵蚀量等因子,进而改变水土流失的状况。从提高植被覆盖度尤其是低覆盖度草地植被的角度出发,定量研究了为改善流域水土流失状况河道外生态需水的具体数额,得出海河流域现状年河道外生态耗水(降水)385亿m^3。另外,为改善河道外生态环境状况将低覆盖度草地提高地提高至中等覆盖度水平,则需要增加生态需水12.5亿m^3。  相似文献   
8.
关于征地制度的思考   总被引:20,自引:0,他引:20  
针对当前农村土地问题的现状.认为调整农村土地关系改革土地制度是解决当前农村问题的关键之一。介绍苏格兰土地改革的经验.提出农村土地转为非农用地的交易中国家应实行限制性措施.可尝试建立“国家失地农民账户”和“国家失地农民保障基金”.从而合理分配土地交易产生的级差收益保障失地农民的合法利益。  相似文献   
9.
Urbanization was associated with loss and transformation of the oak forest in the Twin Cities (Minneapolis and St. Paul) metropolitan area (TCMA) over a recent 7-year interval. Between 1991 and 1998, urbanization increased based on several indicators: population density, area of developed land, and area of impervious surface—total impervious area and area within three classes of increasing degree of imperviousness (protected, affected, and degraded). We quantified relationships between changes in urbanization and changes in several parameters describing the oak forest at the scale of ecological subsection. Increased total and affected impervious area were strongly correlated with decreased area of oak forest when changes of the urbanization indicators and oak were expressed as percentages of the subsection area. Relationships were reversed when changes were expressed as percentages of the 1991 values. Increased population density was strongly correlated with increased loss in numbers and increased isolation of oak patches, but weakly correlated with loss of oak forest area. This is the first study to quantify relationships between changes in urbanization and changes in a specific forest cover type. Our results demonstrate complexities of urbanization impacts on a metropolitan forest resource, and highlight the importance of selected variables, spatial and temporal scales, and expressions of change when quantifying these relationships.  相似文献   
10.
高压线走廊下建设大型公共绿地的探索   总被引:2,自引:0,他引:2  
通过闵行经济技术开发区范围内高压线走廊下的40万m~2非生产性用地建设成大型公共绿地的实践,提出了“以绿养园,以园养园”的新思路,充分体现“谁种养,谁保护,谁得益”的原则,给上海地区乃至全国开发利用高压线走廊下的土地资源,提供了借鉴。  相似文献   
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