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851.
Zhang M  An T  Fu J  Sheng G  Wang X  Hu X  Ding X 《Chemosphere》2006,64(3):423-431
An adsorptive silica-supported titania photocatalyst TiO(2)/SiO(2) was prepared by using nanosized titania (anatase) immobilized on silica gel by the sol-gel technique with the titanium tetra isopropoxide as the main raw material and acetic acid as the acid catalyst. Meanwhile the structure and properties of the TiO(2)/SiO(2) photocatalyst were studied by means of many modern analysis techniques such as TEM, XRD, and BET. Gas-solid heterogeneous photocatalytic decomposition of four carbonyl compounds mixture at low concentration levels over ultraviolet irradiated TiO(2)/SiO(2) photocatalyst were carried out with high degradation efficiencies in a coaxial triple-cylinder-type fluidized bed photocatalytic reactor, which provided efficient continuous contact of ultraviolet photons, silica-supported titania photocatalyst, and gaseous reactants. Experimental results showed that the photocatalyst had a high adsorption performance and a good photocatalytic activity for four carbonyl compounds mixture. Some factors influencing the photocatalytic decomposition of the mixed carbonyl compounds, i.e. the gas flowrate, relative humidity, concentration of oxygen, and illumination time, were discussed in detail. It is found that the photocatalytic reaction rate of four carbonyl compounds decreased in this order: propionaldehyde, acetone, acetaldehyde and formaldehyde.  相似文献   
852.
预应力锚索和微型桩联合处理深基坑失稳事故   总被引:2,自引:0,他引:2  
土钉支护具有经济快捷等优点,但土钉支护单独使用也有其局限性。通过对某土钉支护深基坑在施工过程中发生支护失稳出现险情的原因进行分析,及时地设计预应力锚索和微型桩予以联合加固,有效地控制了该基坑的变形,保证了地下室施工的安全。  相似文献   
853.
Environmental Science and Pollution Research - An objective understanding of the current situation and influencing factors of rural green development in China is an important prerequisite for...  相似文献   
854.
To access organizational resources, subordinates often strive to influence supervisors' impressions. Moreover, subordinates' interactions with supervisors are known to be ripe with emotions. Nevertheless, research on upward impression management has rarely examined how subordinates' emotion regulation in supervisor interactions may shape their tangible outcomes. The present study introduces subordinates' emotional labor toward supervisors as a novel means of upward influence. Building on the emotions-as-social-information model, we propose that supervisor-directed emotional labor indirectly relates with supervisory reward recommendations by shaping supervisors' liking and perceived competence of subordinates. Moreover, we cast supervisors' epistemic motivation as a boundary condition for these indirect relations. We tested these notions using time-lagged data from 377 subordinates and 91 supervisors. When supervisors' epistemic motivation was higher (but not lower), (1) supervisor-directed surface acting related negatively with supervisors' liking and perceived competence of subordinates and (2) supervisor-directed deep acting related positively with supervisors' liking of subordinates. Liking and perceived competence, in turn, related positively with supervisors' willingness to recommend subordinates for organizational rewards. These findings highlight supervisor-directed emotional labor as an upward impression management strategy with both beneficial (deep acting) and detrimental (surface acting) implications, and they illustrate important mechanisms and a key contingency factor for these consequences.  相似文献   
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857.
通过对处理剂环保性能评价及作用效果优选、高密度环保钻井液配方及其钻井液的流变性、失水性、抗温性、抑制性、抗污染等综合性能评价等一系列实验研究,形成了一套适合山前构造带的环保钻井液体系。该钻井液具有无毒、易降解、密度高(2.0g/cm3和2.3g/cm3)、高温高压失水低、流变性好、抗高温可达130~140℃,性能稳定,抑制性、润滑性能好,抗污染能力强,既能够满足复合盐层钻井工程需求,又具环保性能好的特点。  相似文献   
858.
衡阳地质环境复杂,人类工程活动频繁,是湖南省地质灾害高-中易发区。本文对影响地质灾害发生的地形地貌、地质构造、降水、人类活动强度等诸多因子量化处理,将衡阳划分出6个崩塌、滑坡及泥石流灾害高发带及4个塌陷地质灾害高发带;无论在年、月时间尺度上,地质灾害发生数与降水量的相关性均不好,但与80 mm以上降水次数的相关度高(r=0.845),80 mm以上降水可作为地质灾害发生的重要指标;1990年代以来,衡阳地质灾害数呈波动性增长,目前处于灾害高发后的趋缓期。一年中,7月发生地质灾害的几率较大(34.8%)。  相似文献   
859.
Hygroscopicity and optical properties of alkylaminium sulfates   总被引:1,自引:0,他引:1  
The hygroscopicity and optical properties of alkylaminium sulfates (AASs) were investigated using a hygroscopicity tandem differential mobility analyzer coupled to a cavity ring-down spectrometer and a nephelometer. AAS particles do not exhibit a deliquescence phenomenon and show a monotonic increase in diameter as the relative humidity (RH) ascends. Hygroscopic growth factors (GFs) for 40, 100 and 150 nm alkylaminium sulfate particles do not show an apparent Kelvin effect when RH is less than 45%, whereas GFs of the salt aerosols increase with initial particle size when RH is higher than 45%. Calculation using the Zdanovskii-Stokes-Robinson mixing rule suggests that hygroscopic growth of triethylaminium sulfate-ammonium sulfate mixtures is non-deliquescent, occurring at very low RH, implying that the displacement of ammonia by amine will significantly enhance the hygroscopicity of (NH4)2SO4 aerosols. In addition, light extinction of AAS particles is a combined effect of both scattering and absorption under dry conditions, but is dominated by scattering under wet conditions.  相似文献   
860.
红碱淖是中国最大、最年轻的沙漠淡水湖,水域面积67平方公里。通过数据收集统计及打分计算的方式对红碱淖水环境质量、生态环境质量、水生态健康进行定量分析,结果表明,红碱淖水环境质量从1981年至2010年有逐渐恶化的趋势;2010年红碱淖生态系统健康综合指数为59.86,属于中等水平,已经受到了一定影响;生态质量综合评价值为81.6分,具有较高的保护价值。并对造成红碱淖水质和生态系统逐步恶化的原因进行解析,同时提出相应的对策。  相似文献   
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