硅铝比和NiO对ZSM-5协同低温等离子体降解甲苯的影响

研究了不同硅铝比的ZSM-5与Ni/ZSM-5分子筛协同低温等离子体技术对甲苯降解性能的影响.以Ni O(Nickel Oxide)为活性组分,采用浸渍法对ZSM-5分子筛进行改性,利用氮气吸附脱附(BET)、X射线衍射仪(XRD)、X射线光电子能谱分析(XPS)、H_2程序升温还原(H_2-TPR)、NH_3程序升温脱附(NH_3-TPD)、Toluene程序升温脱附(Toluene-TPD)等技术表征样品的物理化学性质.考察了硅铝比对ZSM-5与Ni/ZSM-5分子筛体系中甲苯的吸附性能,研究了不同放电电压下硅铝比对甲苯降解率、碳平衡及二氧化碳选择性的影响,并采用气相色谱-质谱联用仪(GC-MS)分析了催化剂表面的有机产物.结果表明:硅铝比不但影响分子筛本身的物理化学特性(比表面积、氧化还原性能、表面酸性、疏水性等),还会影响Ni的负载形态和方式,更高的硅铝比与Ni O的负载能促进甲苯深度氧化,减少副产物,提高碳平衡和二氧化碳选择性.     

我国煤矿事故的特征及微观原因分析

按照事故总量、所有制结构和事故类型对我国煤矿安全事故分析,虽然近几年我国安全生产形势有所好转,事故起数和死亡人数都有不同程度的下降,但事故总量依然很大,与发达国家相比还有一定差距,安全生产形势依然严峻。从微观层面分析了主要原因,包括开采自然条件复杂、管理方法和技术装备水平有限、煤矿企业超能力生产以及从业人员素质不高等。     

A steam dried municipal solid waste gasification and melting process

Considering high-moisture municipal solid waste (MSW) of China, a steam dried MSW gasification and melting process was proposed, the feasibility was tested, and the mass and energy balance was analyzed. Preliminary experiments were conducted using a fixed-bed drying apparatus, a 200 kg per day fluidized-bed gasifier, and a swirl melting furnace. Moisture percentage was reduced from 50% to 20% roughly when MSW was dried by slightly superheated steam of 150°C?C350°C within 40 min. When the temperature was less than 250°C, no incondensable gas was produced during the drying process. The gasifier ran at 550°C?C700°Cwith an air equivalence ratio (ER) of 0.2?C0.4. The temperature of the swirl melting furnace reached about 1240°C when the gasification ER was 0.3 and the total ER was 1.1. At these conditions, the fly ash concentration in the flue gas was 1.7 g·(Nm³)^?1, which meant over 95% fly ash was trapped in the furnace and discharged as slag. 85% of Ni and Cr were bound in the slag, as well as 60% of Cu. The mass and energy balance analysis indicates that the boiler heat efficiency of an industrial MSW incineration plant reaches 86.97% when MSW is dried by steam of 200°C. The boiler heat efficiency is sensitive to three important parameters, including the temperature of preheated MSW, the moisture percentage of dried MS Wand the fly ash percentage in the total ash.     

最优曲线投影动态聚类指标及在洪水分类中的应用——以南京站洪水为例

聚类数和聚类方法是聚类分析研究的核心,有着及其重要的实用价值。在投影寻踪动态聚类模型的基础上,通过引入S型曲线作为投影方式,并据此首次提出了能够同时确定最佳聚类数和对应聚类结果的最优曲线投影动态聚类指标。该动态聚类指标完全由数据驱动,具有计算简便并且物理意义清晰等特点。南京站洪水过程的应用结果表明:最优洪水动态分类指标在洪水聚类分析中是有效的,能提供明确、客观及合理的分类数和分类结果。     

Assessment of toxic elements in road dust from Hutou Village,China: implications for the highest incidence of lung cancer

Environmental Science and Pollution Research - We attempt to understand the pollution characteristics and carcinogenic risk of toxic elements around Hutou Village, Xuanwei City, Yunnan Province,...     

Health and economic impacts from PM2.5 pollution transfer attributed to domestic trade in China: a provincial-level analysis

Environmental Science and Pollution Research - In recent years, severe air pollution has had a serious impact on the health and economy of residents and has attracted great attention. Due to the...     

Modelling the symmetrical and asymmetrical effects of global oil prices on local food prices: A MENA region application

Environmental Science and Pollution Research - This paper explores the complex nexus between the global oil prices and the food prices of the Middle East and North Africa (MENA) region during the...     

Report: transboundary hazardous waste management. part II: performance auditing of treatment facilities in importing countries.

Before implementing the self-monitoring model programme of the Basel Convention in the Asia, Taiwan has conducted a comprehensive 4-year follow-up project to visit the governmental authorities and waste-disposal facilities in the countries that import waste from Taiwan. A total of nine treatment facilities, six of which are reported in this paper, and the five countries where the plants are located were visited in 2001-2002. France, Belgium and Finland primarily handled polychlorinated biphenyl capacitors, steel mill dust and metal waste. The United States accepted metal sludge, mainly electroplating sludge, from Taiwan. Waste printed circuit boards, waste wires and cables, and a mixture of waste metals and electronics were the major items exported to China. Relatively speaking, most treatment plants for hazardous waste paid close attention to environmental management, such as pollution control and monitoring, site zoning, system management regarding occupational safety and hygiene, data management, permits application, and image promotion. Under the tight restrictions formulated by the central environment agency, waste treatment plants in China managed the environmental issues seriously. For example, one of the treatment plants had ISO 14001 certification. It is believed that with continuous implementation of regulations, more improvement is foreseeable. Meanwhile, Taiwan and China should also continuously enhance their collaboration regarding the transboundary management of hazardous waste.     

对构建以本质安全为主体的煤矿安全文化体系的探讨——兼论徐州矿务集团创建本质安全型企业的实践

简要介绍了安全文化的起源、基本概念 ,对煤矿安全文化、本质安全给予了定义。较系统地论述了本质安全的哲学思想。从煤矿行业特征、实践“三个代表”、全面建设小康社会、应对WTO的挑战、现有条件等方面重点阐明了煤矿安全文化体系应以本质安全为主体内容。并以徐州矿务集团有限公司开展“创建本质安全型企业”活动的具体实践 ,说明了应如何在煤矿企业推行以本质安全为主体的煤矿安全文化。