环境中污染源废气检测方法及影响因素分析

对污染源废气监测原理进行了简单分析,阐述了当前我国常用的环境中污染源废气检测方法,并对废气检测影响因素及质量控制进行了深入探究。     

Applications of high-gravity technologies in gas purifications: A review

The traditional gas purification techniques such as wet gas desulfurization, with their advantages of large-scale implementation and maturity, have still been widely used. However, the main drawback of these techniques is the low transfer efficiency, which normally needs towers as tall as tens of meters to remove the pollutants. Therefore, new technologies which could enhance the mass transfer efficiency and are less energy-intensive are highly desirable. As a process intensification technology, high-gravity technology, which is carried out in a rotating packed bed(RPB), has recently demonstrated great potential for industrial applications due to its high mass transfer efficiency, energy-saving, and smaller volume. This consequently provides higher efficiency in toxic gas removal, and can significantly reduce the investment and operation costs. In this review, the mechanism,characteristics, recent developments, and the industry applications of high-gravity technologies in gas purifications, such as hydrogen sulfide, nitrogen oxide, carbon dioxide, sulfur dioxide, volatile organic compounds and nanoparticle removal are discussed, most of the demonstration projects and practical application examples in gas purification come from China. The perspective and prospective of this technology in gas purification and other fields are also briefly discussed.     

室内空气状况及污染防治措施

随着室内污染问题的日趋严重,我国室内空气污染状况、来源与危害及主要的防治措施也越来越受到关注。     

黄陵矿区煤矿井下围岩喷涌气体致灾机理及防治措施

鄂尔多斯盆地南缘黄陵矿区黄陵一号等煤矿在采掘过程中出现井下围岩大量气体喷涌现象,导致矿井停采停掘,对煤矿安全生产构成严重威胁。为了揭示喷涌气体的成因及致灾机理,以地面钻孔补充勘探和钻探资料及围岩气体地球化学参数测试数据为基础,采用气样地球化学特征分析、热演化史模拟、烃源岩对比、运移通道识别等多种方法,查明围岩气体的砂岩储集层平面及剖面分布特征,研究区内异常致灾围岩气体的成因类型和来源,分析围岩气体异常喷涌的致灾机理,建立以顶底板砂岩探抽为主的分源综合立体抽采防治模式。研究结果表明:(1)该区煤矿井下围岩气体喷涌具有突发性、隐蔽性、涌出集中和涌出量大等特点,涌出气体主要成分为甲烷,气体主要来源于围岩;(2)顶、底板围岩气体主要为原油伴生热解成因的油型气,生气源岩为上三叠统延长组长7等段腐泥型主力烃源岩,经燕山运动形成的北东向基底断层及其周围大规模垂直裂缝运移而来;(3)油型气主要储集砂岩层呈区带式分布,受构造和岩性双重控制;(4)针对围岩油型气以游离态储集在砂岩中、由采动裂隙导通涌出的特点,采用分源综合立体抽采的防治模式进行围岩气灾害治理,取得了良好的治理效果。     

致病性弧菌及其噬菌体防治研究进展

弧菌广泛分布于海洋、咸水和淡水生态系统中，因其高丰度和高生物量使其在水生环境中发挥着关键作用，并成为人类和海洋动物的重要病原体。在过去的几十年间，随着海洋水产养殖业的快速增长，全球范围内弧菌相关疾病的报道越来越多。抗生素的使用是目前控制弧菌病爆发最常用的方法，但细菌耐药和超级细菌的问题又引起了人们的广泛关注。因此，噬菌体疗法在近年来得到了复兴。噬菌体不仅可以治疗细菌病也可以预防细菌病。然而，在为水产养殖业提供具有商业潜力的可靠、可重复的处理方法之前，仍有若干科学和技术挑战需要进一步研究。本文综述了致病性弧菌及其噬菌体防治的潜力和挑战。     

A geospatial framework to support integrated biogeochemical modelling in the United Kingdom

Anthropogenic impacts on the aquatic environment, especially in the context of nutrients, provide a major challenge for water resource management. The heterogeneous nature of policy relevant management units (e.g. catchments), in terms of environmental controls on nutrient source and transport, leads to the need for holistic management. However, current strategies are limited by current understanding and knowledge that is transferable between spatial scales and landscape typologies. This study presents a spatially-explicit framework to support the modelling of nutrients from land to water, encompassing environmental and spatial complexities. The framework recognises nine homogeneous landscape units, distinct in terms of sensitivity of nutrient losses to waterbodies. The functionality of the framework is demonstrated by supporting an exemplar nutrient model, applied within the Environmental Virtual Observatory pilot (EVOp) cloud cyber-infrastructure. We demonstrate scope for the use of the framework as a management decision support tool and for further development of integrated biogeochemical modelling.     

两级伸缩式液压缸与四柱两级滑轨的故障分析与排除

本文通过对两级伸缩式液压缸与四柱滑轨结合使用中所出现问题及处理过程的阐述,提出了在液压系统设计与制造中,准确的原理仅仅是基础,其上还有许许多多的细枝末节需要仔细修剪,比如污染、噪声、温度、泄漏以及与机械的协调等等。     

Incidence and costs of bicycle-related traumatic brain injuries in the Netherlands

The main cause of death and serious disability in bicycle accidents is traumatic brain injury (TBI). The aim of this population-based study was to assess the incidence and costs of bicycle-related TBI across various age groups, and in comparison to all bicycle-related injuries, to identify main risk groups for the development of preventive strategies.Data from the National Injury Surveillance System and National Medical Registration were used for all patients with bicycle-related injuries and TBI who visited a Dutch emergency department (ED) between 1998 and 2012. Demographics and national, weighted estimates of injury mechanism, injury severity and costs were analysed per age group. Direct healthcare costs and indirect costs were determined using the incidence-based Dutch Burden of Injury Model.Between 1998 and 2012, the incidence of ED treatments due to bicycle-related TBI strongly increased with 54%, to 43 per 100,000 persons in 2012. However, the incidence of all bicycle-related injuries remained stable, from 444 in 1998 to 456/100,000 in 2012. Incidence of hospital admission increased in both TBI (92%) and all injuries from cycling (71%). Highest increase in incidence of both ED treatments and hospital admissions was seen in adults aged 55+. The injury rate of TBI per kilometre travelled increased (44%) except in children, but decreased (−4%) for all injuries, showing a strong decrease in children (−36%) but an increase in men aged 25+, and women aged 15+. Total costs of bicycle-related TBI were €74.5 million annually. Although bicycle-related TBI accounted for 9% of the incidence of all ED treatments due to cycling, it accounted for 18% of the total costs due to all bicycle-related injuries (€410.7 million). Children and adolescents (aged 0–24) had highest incidence of ED treatments due to bicycle-related injuries. Men in the working population (aged 15–64) had highest indirect costs following injuries from cycling, including TBI. Older cyclists (aged 55+) were identified as main risk group for TBI, as they had highest ED attendance, injury rate, injury severity, admission to hospital or intensive care unit, and costs.Incidence of ED treatments due to cycling are high and often involve TBI, imposing a high burden on individuals and society. Older cyclists aged 55+ were identified as main risk group for TBI to be targeted in preventive strategies, due to their high risk for (serious) injuries and ever-increasing share of ED visits and hospital admissions.     

A review on various after treatment techniques to reduce NOx emissions in a CI engine

NOx emissions have always been a main concern in the development of diesel engines. This paper summarizes the studies about NOx emission reduction in diesel engines. The need for meeting the stringent requirements with regard to NOx emissions in a diesel engine has led to the development of a range of after treatment techniques. After treatment methods are required to reduce NOx emissions that cannot be controlled by fuel composition and combustion phenomena. Current after treatment techniques that are being employed are Selective Catalytic Reduction (SCR), Lean NOx Trap (LNT) and SCR Filter (SCRF). The benefits and constraints of different types of SCR are discussed. Urea SCR is a prominent well proven technology. Urea SCR produces 96–99% conversion efficiency with the help of a reductant NH₃. The operating parameters such as nature of catalyst, temperature range of catalyst, flow of DEF (Diesel Exhaust fluid) to injector and mixing of NH₃ and NOx are discussed. Hybrid SCR such as Cu-SCR + Fe-SCR, SCR + LNT moderates fuel consumption and augments the catalytic activity at low temperature. SCRF has low cell density (200–300 csi vs 400–600 csi for SCR), and also has lower deNOx efficiency for a number of reasons. Pre-stored NH₃ and Preheating helps in low temperature reaction of SCRF. Technical problems in aqueous urea systems have led to the evolution of solid SCR system (SSCR). This review incorporates the study of solid ammonium salts decomposition, temperature range of the salts and infrastructure required for SSCR.     

2016~2018年甘肃省市售蔬菜中铅汞污染状况及人体健康风险分析

目的 对甘肃省14个市州蔬菜中铅汞进行三年的采样监测,掌握铅汞重金属污染的基本情况并对人体健康风险进行了分析。方法 在全省14个市州共采集样品1213份,依据国标方法进行铅汞含量的测定,采用尼梅罗综合污染指数法对蔬菜中铅和汞污染程度进行评价,用目标危害指数法(THQ)和危害指数(HI)评价蔬菜中铅汞对成人和儿童的健康风险。结果 各类蔬菜中均检出了铅和汞,其中鳞茎类中的铅和茎类蔬菜中的汞检出率均达到了100%；块根和块茎类蔬菜铅的超标率为3.76%；汞含量除在茎类蔬菜中超标率为1.34%外,在其余种类中均未有超标。从铅汞的综合污染指数来看,除茎类蔬菜以外,其他都表现为Pb＞Hg,铅对蔬菜重金属污染贡献较大,其中瓜菜类和鳞茎类的铅含量综合污染指数分别为0.61和0.52,属于轻度污染；茄果类和块根块茎类蔬菜的铅含量综合污染指数分别达到了4.68和4.40,污染较严重。居民通过蔬菜摄入的铅汞的暴露风险儿童高于成人,但THQ和HI均小于1,对人体健康造成的影响不明显。结论 本次研究中甘肃省市售蔬菜中少数受到重金属铅的污染,其余蔬菜中铅汞含量对健康影响均在安全范围内。