Evaluating the potential of CNT-supported Co catalyst used for gas pollution removal in the incineration flue gas

This study investigated the use of Cu/Al₂O₃, Co/Al₂O₃, Fe/Al₂O₃, and Ni/Al₂O₃ catalysts for the growth of carbon nanotubes (CNTs). These CNTs were used as support for Co catalyst preparation and Co/CNT catalysts were applied to a catalytic reaction to remove BTEX, PAHs, SO₂, NO, and CO simultaneously in a pilot-scale incineration system. The analyzed results of EDS and XRD showed low metal content and good dispersion characteristics of the Al₂O₃-supported catalysts by excess-solution impregnation. FESEM analyzed results showed that the CNTs that were synthesized from Co, Fe, and Ni catalysts had a diameter of 20 nm, whereas those synthesized from Cu/Al₂O₃ had a diameter of 50 nm. Pilot-scale test results demonstrated that the Co/CNT catalyst effectively removed air pollutants in the catalytic reaction and that there was no obvious deactivation by Pb, water vapor, and coke deposited in the process. The thermal stabilization at 250 °C and hydrophobicity properties of CNTs enhanced the application of CNT catalysts in flue gas.     

Characterization of odorants in contrasting ecotypes of Lake Taihu: algae-dominated versus macrophyte-dominated zones

Environmental Science and Pollution Research - Globally, odorant incidents are occurring at an increasing frequency, magnitude, and duration under the dual influences of eutrophication and climate...     

不同畜禽粪与化肥配施对黑土中Cu有效性的影响及相关因素分析

本文通过培养试验,研究了不同畜禽粪与化肥配施对黑土中Cu总量及形态3年内动态变化的影响,并对影响Cu形态变化的相关因素进行了分析.研究结果显示:不同畜禽粪与化肥配施增加了土壤中Cu的总量,增加效果依次为:猪粪与化肥配施鸡粪与化肥配施牛粪与化肥配施.不同畜禽粪与化肥配施导致了土壤中各形态Cu含量增加,增幅依次为:猪粪与化肥配施鸡粪与化肥配施牛粪与化肥配施.此外,不同畜禽粪与化肥配施还导致了土壤中酸可提取态Cu和残渣态Cu比例增加,可还原态Cu和可氧化态Cu比例减少,变化幅度均呈现猪粪与化肥配施鸡粪与化肥配施牛粪与化肥配施的规律.由于酸可提取态Cu占全Cu比例较小(增加后比例仍不足2%),故其对Cu有效性的影响微乎其微,而残渣态Cu的增加,可还原态、可氧化态Cu的减少均表明:不同畜禽粪与化肥配施降低了土壤中Cu的有效性.对于影响Cu形态的相关因素分析,研究结果表明:土壤中各形态Cu与pH值间相关性不显著,但其与有机质含量间相关性极其显著.酸可提取态、残渣态Cu与有机质含量呈显著负相关,可还原态、可氧化态Cu与有机质含量呈显著正相关.此外,畜禽粪与化肥配施增加了土壤中各形态Cu与pH值间的相关性,但对其与有机质含量间关系影响不大.     

西安郊区泾河秋、冬季大气黑碳变化及粒径特征

利用西安郊区泾河大气成分站ρ(BC)(BC为黑碳)、粒子数浓度资料和观象台自动站、探空站数据,对西安郊区秋、冬季ρ(BC)变化特征、粒径分布特征和变化原因进行了分析.结果表明:①泾河郊区ρ(BC)比城区的低.城区ρ(BC)日变化呈三峰特征,峰值分别出现在凌晨02:00、清晨07:00和傍晚20:00,分别为17.0、12.5和21.5 μg/m3.泾河郊区ρ(BC)日变化呈双峰特征,峰值出现在上午09:00和晚上23:00,数值分别为5.5和6.1μg/m3;谷值出现在清晨06:00和下午16:00,数值分别为4.9和2.6μg/m3.②ρ(BC)与不同粒径颗粒物数浓度关系不同,其中与粒径＜4.0 μm粒子的数浓度成正比,与粒径≥4.0 μm粒子(如沙尘)的数浓度成反比;波长指数分析表明,沙尘可致ρ(BC)实测值偏大.③ρ(BC)与近地面逆温强度有密切相关性,R(相关系数)达到0.412 5(P ＜0.000 1);风速小于1.5 m/s时BC易堆积,大于1.5 m/s时则相反;连续降水对BC清除效果显著.     

Prenatal diagnosis of holoprosencephaly in two fetuses with der (7)t(1;7)(q32;q32)pat inherited from the father with double translocations

The presence of two independent translocations in one person is rare. Herein, we report the prenatal diagnosis of two sibling fetuses with holoprosencephaly, whose father is a carrier of double translocations. The karyotype of the father is 46,XY, t(1;7) (q32;q32), t(14,15) (q32.1;q26.3). The two fetuses had variable facial dysmorphisms and identical cytogenetic abnormality—a derivative (7) t(1;7) (q32;q32) inherited from the father. The proband 1 showed a small mouth, a single median eye and a proboscis above the eye, while the proband 2 showed hypotelorism, a flat nose, cleft lip and cleft palate. Both fetuses also had alobar holoprosencephaly. Haploinsufficiency of the sonic hedgehog gene at 7q36 does account for the occurrence of holoprosencephaly in the two fetuses with a deletion of distal 7q (7q32 → qter). Copyright © 2003 John Wiley & Sons, Ltd.     

Heterogenous impacts of components in urban energy metabolism: evidences from gravity model

Environment, Development and Sustainability - The undergoing rapid urbanization is bringing dramatic economic development and social improvement for cities, but also a series of problems associated...     

水分对煤中瓦斯放散初速度影响研究

为了研究水分对煤中瓦斯放散初速度的影响,对水分含量分别为3%,5%及7%的不同粒径的煤样进行了测定,绘制了不同粒径煤中瓦斯放散初速度随水分变化的曲线图,并从煤对瓦斯的吸附、解吸特性及渗透率等方面深入全面地分析了产生该曲线变化趋势的原因。     

基于GMM模型的煤矿顶板事故致死人数预测

为了解决目前常用预测模型对随机波动性较大数据预测精度偏低的问题,文章在灰色预测GM(1,1)的基础上引入马尔可夫状态转移矩阵,建立了灰色马尔可夫预测模型(GMM),并将该法运用到煤矿顶板致死人数的预测中。经计算GMM模型的预测平均相对误差为1.181%,最大相对误差3.426%,与GM(1,1)法相比,后者精度分别提高了21倍和13倍。     

Development of Emission Factors for Polyamide Processing

ABSTRACT

Emission factors for selected volatile organic compounds (VOCs) and particulate material were developed during processing of commercial grades of polyamide 6, polyamide 66, and polyamide 66/6 resins. A small commercial-type extruder was used, and melt temperatures ranged from 475 to 550 °F. An emission factor was calculated for each substance measured and is reported as pounds released to the atmosphere per million pounds of polymer resin processed. Scaled to production volumes, these emission factors can be used by processors to estimate emission quantities from similar polyamide extrusion operations.     

A real-time warning model for teamwork performance and system safety in nuclear power plants

In order to increase system safety and team performance, this study aimed to develop a real-time warning model (RTWM) by assessing team response time, error rates, and mental workload. Toward this goal, the group method of data handling (GMDH) algorithm was applied to physiological indices to predict team performance. Then fuzzy logic, fuzzy inference and linguistic variable sets representing the Team Performance and Safety Index were applied to construct the RTWM. To model the RTWM, experiments were conducted on computer-supported cooperative work (CSCW) in the personal computer transient analyzer (PCTRAN) simulator. The simulator and teamwork are designed to simulate the real tasks of the control room of the Fourth Nuclear Power Plant (FNPP) in Taiwan. In addition, important physiological parameters, the NASA-TLX questionnaire, team response time, and team error rates were collected from 39 participants. The results revealed that there was a significant positive correlation between the error rates of teamwork and the interval of event arrival time. This indicated that a pre-alarm device is necessary because vigilance decreased with time. Moreover, a predictive teamwork performance model applying the GMDH algorithm and the RTWM with a fuzzy inference system was developed in this study. The proposed model can efficiently predict teamwork performance to maintain appropriate mental workload as well as ensure system safety.