硬化路面与温度场响应模型研究

硬化路面是城市热环境效应影响因素中较为重要的一个因素.笔者在研究了深圳市城市热效应的基础上,建立了一个三维动态模型对硬化路面条件下的温度场进行模拟.通过将模型的计算结果和在深圳的实测结果进行对比,发现2条曲线吻合较好,模拟结果十分接近实测结果.模型模拟结果还证明了硬化路面由于铺筑的材料具有较大蓄热、导热的能力,而且透水性差,因此温度升降都很快,对城市的热效应贡献大;城市绿化隔离带对城市温度场具有很好的调节作用,因此合理配置城市中的绿地对城市区域微热环境的改善能够起到很好的作用.      

Preliminary analysis of single flash combined with binary system using thermodynamic assessment: a case study of Dieng geothermal power plant

This paper addressed the performance of single flash combined with a binary system that was proposed in the Dieng geothermal power plant by applying thermodynamic assessment methods. A set of mathematical equations from the plant was developed and solved iteratively using engineering equation solver. The results showed that the available exergy of the produced fluid from production wells is 66,204 kW. The performance of an existing single-flash power plant indicated 24,300 kW of net power output. The proposed design of single flash combined with a binary system improves the power output by 17.16% to 27,786 kW. The second law efficiency increases from 36.7% to 41.97% while the first law efficiency increases from 11.62% to 13.61%.     

石油污染土壤多酚氧化酶的动力学及热力学特征

土壤多酚氧化酶是一种氧化还原酶,能够将土壤中芳香族化合物氧化成醌,促进土壤中石油类物质的分解转化.以距大庆油田工作区不同距离（1、5、15 km）的石油污染地为对象,研究不同温度下石油污染裸地及羊草（Leymus chinensis）修复地的土壤多酚氧化酶活性及其动力学和热力学特征的变化.结果表明:土壤多酚氧化酶活性随温度和底物浓度的增加而逐渐增大,在温度为30℃或40℃、底物浓度为80 mmol/L或160 mmol/L时达到最大值;各样地土壤酶的动力学参数K_m（Mihaelis常数）随温度的变化规律不同,V_max（酶促反应最大速度）和V_max/K_m（催化效率）随温度升高而逐渐增大,均在30℃或40℃时达到最大值;热力学参数Q₁₀（温度系数）、ΔH（活化焓）、ΔS（活化熵）随温度变化差异不显著,ΔG（活化自由能）随温度升高呈逐渐增加趋势.在同一温度下,石油污染裸地土壤多酚氧化酶活性高于羊草修复地;K_m和V_max/K_m在各样地均表现为无规律性变化,V_max最大值出现在距油田工作区5 km处的裸地（BMP）,最小值出现在距油田工作区5 km处的羊草修复地（LMP）;Q₁₀、E_a（活化能）、ΔH、ΔS的最大值均出现在距油田工作区1 km处的裸地（BVP）,最小值均出现在距油田工作区1 km处的羊草修复地（LVP）.研究显示,升温和植物修复对土壤多酚氧化酶活性的反应特征有较大影响.      

荧光光谱法研究丙酮与牛血清白蛋白的相互作用特征

在模拟动物体生理条件和不同温度下,用荧光光谱、三维荧光光谱、同步荧光光谱、紫外可见吸收光谱法等研究了丙酮(ACET)与牛血清白蛋白(BSA)的相互作用,证实了丙酮有很强的猝灭BSA荧光强度的能力.分别用Sterr-Volmer方程、Lineweaver-Burk双倒数方程和热力学方程等分析和处理试验数据,得到了它们相互作用的生成常数KLV(平均值为7.073×106L·mol-1)、热力学参数(△Hθ、△Gθ和△Sθ的平均值分别为-3.982kJ·mol-1、-26.51 kJ·mol-1和73.31J·K-1)和结合位点数(平均值为1.266)等.这为研究ACET对BSA构象的影响、ACET的毒理效应和生物学效应提供了重要信息.     

新疆石化工业区颗粒物含水量和酸度对二次无机组分形成的影响

大气二次污染物是新疆独山子区大气污染物的重要组成部分,研究大气中二次组分的转化过程对区域大气污染治理有着重要意义.对新疆独山子区2015年9月至2016年7月采集到的样品进行水溶性组分分析.结果表明,水溶性无机离子(TWSIs)表现出与PM_2.5一致的季节变化,为冬季(67.86μg·m^-3)>秋季(13.77μg·m^-3)>春季(10.09μg·m^-3)>夏季(4.85μg·m^-3);冬季二次无机离子(NH⁺₄、SO^2-₄和NO^-₃)占TWSIs的98%;结合气溶胶热力学模型(E-AIM)探讨独山子区大气颗粒污染物中颗粒相含水量以及颗粒酸碱性;表明独山子区颗粒物呈酸性,年均原位pH为0.81,其中冬季样品的pH(2.93)值最高;颗粒含水季节变化为冬季(331.32μg·m^-3)>秋季(5.91μg·...     

TiO2@酵母微球吸附废水中的荧光增白剂-VBL及再生研究

采用静电自组装的方法制备出具有草莓结构的TiO2@酵母微球作为吸附材料,对阴离子型荧光增白剂-VBL(FWA-VBL)废水进行吸附研究,考察了溶液pH、溶液初始浓度和TiO2@酵母投加量对吸附效果的影响.结果表明,酸性条件有利于TiO2@酵母微球对FWA-VBL的吸附,平衡吸附量随着溶液初始浓度的增加而增加,随着TiO2@酵母微球投加量的增加而减小.TiO2@酵母对FWA-VBL的吸附行为更加符合Langmuir等温模型,在温度为323.15K下最大吸附量为167.50mg/g; 吸附动力学符合二级动力学方程; 热力学参数表明吸附过程是自发的吸热过程.归因于光催化-吸附耦合效应,TiO2@酵母微球展现出了良好的原位再生能力.H2O2的添加有助于提高TiO2@酵母微球的再生性能.     

Removal of Mo(VI) from aqueous solutions using sulfuric acid-modified cinder: kinetic and thermodynamic studies

Removal of Mo(VI) from aqueous solutions was investigated using cinder modified by sulfuric acid. Various parameters such as pH, agitation time, Mo(VI) concentration, and temperature have been studied. The maximum adsorption of Mo(VI) occurred at pH between 4.0 and 6.0. Kinetic studies showed that the adsorption generally obeyed a pseudo second-order model. The activation energy was 31.4?kJ?mol^?1, indicating that the adsorption process was governed mainly by interactions of physical nature. Furthermore, application of Langmuir and Freundlich isotherm models to the adsorption equilibrium data showed that the adsorption behavior obeyed the Langmuir model. The adsorption capacity was found to be 10.8?g Mo(VI)?kg^?1 adsorbent. Finally, thermodynamic parameters such as ΔH ⁰, ΔS ⁰, and ΔG ⁰ were also evaluated, which showed that the adsorption of Mo(VI) on the treated cinder was endothermic, entropy increasing, and spontaneous. In conclusion, the sulfuric acid-modified cinder was shown to be an inexpensive, effective, and simple adsorbent for the removal of Mo(VI) from water.     

Thermodynamic investigation of the effect of oxygen and hydrogen chloride potential upon generation and decomposition behavior of dioxins

The thermodynamic equilibrium of the C‐H‐O‐Cl system has been calculated to elucidate the generation and decomposition behavior of dioxins, and is discussed from the viewpoint of the oxygen and hydrogen chloride potential. The dioxins behavior is greatly dependent on the oxygen potential, i.e. higher temperature and oxygen potential lead to the complete decomposition of dioxins, while low hydrogen chloride potential under insufficient oxygen condition leads to an increase of multi‐chlorine displacement of dioxins.     

Removal of Eu3+, Ce3+, Sr2+, and Cs+ ions from radioactive waste solutions by modified activated carbon prepared from coconut shells

As a biomass agricultural waste material, coconut shells were used for the preparation of high-quality modified activated carbon. Chemical modification of the surface of the prepared activated carbon is done by oxidation using H₂O₂ and HNO₃, respectively. The surface area and pore volume of the coconut shells activated carbon are increased by the chemical modification, and followingly the removal of the metals is improved. The structural morphology and composition of the modified activated carbon coconut shells (MACCS) were evaluated by Fourier transform infrared (FTIR) spectra, thermogravimetric analysis–differential thermal analysis (TGA-DTA), scanning electron microscope (SEM), X-ray diffraction (XRD), surface area analysis (SAA), X-ray fluorescence (XRF), and carbon, hydrogen, nitrogen, and sulfur (CHNS) elemental analysis. The prepared MACCS has reasonably good chemical stability. The influence of solution pH, contact time, adsorbent dosage, adsorption temperature, initial metal concentrations, and interfering ions on the adsorption performance of the investigated ions onto the prepared sorbent was examined by a batch method. The selectivity sequence for sorption of Eu³⁺, Ce³⁺, Sr²⁺, and Cs⁺ ions on MACCS was found to be Eu^3+?>?Ce^3+?>?Sr^2+?>?Cs⁺. The saturation capacities of MACCS for the studied metal ions were found to be 136.84, 85.55, 69.85, and 60.00?mg?g^?1 for Eu³⁺, Ce³⁺, Sr²⁺, and Cs⁺ ions, respectively. The thermodynamic parameters, ΔH°, ΔS°, and ΔG° were also evaluated.     

城市区域光热资源特征

利用昆明城内外辐射、风湿产测资料,分析了昆明地区光温的日变化规律、城内外差异等特征,获得了昆明市有丰富的可利用光热资源的结论。