试论环境影响评价中的公众参与

环境影响评价是我国环保领域的基本制度之一,公众参与在环评中的作用是不可替代的.本文从公众参与的发展沿革、法律规定等方面进行了具体阐述,并根据作者在环评工作中的实例总结了有关公众参与的体会和心得.     

快速成形技术的现状及进展

介绍了快速成形技术的工艺过程、应用及几种典型的快速成形工艺 ,并分析了影响其精度和速度的普遍存在的问题及进展     

浅谈生物环境材料研究

采用“生物菌化”和“蛋白变性”技术处理秸秆植物（包括渣、壳、饼），加工制造可降解的环境材料。该技术具有废料再利用、清洁生产，产品无害可降解、废弃后可作为饲料和肥料的特点。     

Kinetic analysis of photocatalytic oxidation of gas-phase formaldehyde over titanium dioxide

Degradation of formaldehyde with different initial concentration over titanium dioxide was carried out in a photocatalytic reactor. Photocatalytic rates were well described by the simplified Langmuir-Hinshelwood model. The kinetic analysis shows that the apparent first-order reaction coefficient is lower and half-life of photocatalysis is longer for low concentration than for high concentration formaldehyde. A network formation model of the photocatalytic products was established. Experimental results and analysis demonstrate that carbon dioxide concentration and carbon monoxide concentration in gas phase vary exponentially with the illumination time and may be even higher than gas-phase formaldehyde concentration if there is much pre-adsorbed formaldehyde in adsorption equilibrium on catalysts before illumination. Carbon monoxide is found to be one of the by-products during formaldehyde photooxidation.     

活性炭悬浮填料在MBBR中的对比实验

填料的结构,材质等因素影响到生物膜的性状和水力学特性,是决定移动床生物膜反应器处理效果的关键因素。本文分别选取了5种含活性炭比例不同的填料以及一种不含活性炭的参照填料,分别从亲水性、COD与NH4+-N的去除、微生物量以及微生物种类方面对各填料在相同的运行条件下进行了比较研究。实验结果表明,含活性炭的填料在亲水性能、挂膜速度,生物量浓度等方面比不含有活性炭的填料有明显的优势。在含活性炭的填料中,25%的填料挂膜快,处理效果稳定,受外界环境影响较小。     

某油田企业职业健康体检结果分析与对策

对2007年度某油田企业职业健康体检结果样本进行了分析,并提出相应对策。     

青岛冬季霾-沙尘重污染过程PM1理化特征及来源分析

对2018年11月21日~12月2日期间青岛市大气PM₁的质量浓度、化学组分和数浓度进行连续观测,结合国控站点监测数据和气象条件,分析青岛市秋末冬初一次典型霾-沙尘重污染过程的特征及污染物来源.结果表明：本次污染过程可分为霾前（11月21~23日）、霾期（11月24~25日）、霾-沙尘叠加期（11月26日）、沙尘期（11月27~29日）、沙尘后（11月30日~12月2日）5个发展阶段,观测期间PM₁质量浓度为（40±20）μg/m³,霾期PM₁为沙尘期的2.03倍.冷锋锋前以人为污染物气团为主,锋后以冷干沙尘气团为主,并在长距离传输中保持干燥,受沙尘传输过程中经过区域的影响较小,导致沙尘阶段PM_2.5和PM₁₀错峰12h出现.霾期PM₁中SO₄^2-、NO₃^-质量浓度比霾前分别升高73%、111%,SOR、NOR分别升高28%、67%,表明霾期NO₃^-的二次转化明显升高.PM₁中NH₄⁺主要以（NH₄）₂SO₄和NH₄NO₃形式存在,为富氨条件.本次沙尘事件气团传输过程中途经山西、河北、山东西北部等污染物高强度排放区域,前锋到达青岛时,携带的人为污染物占主导,导致沙尘期PM₁中OC、EC占比为霾期的1.73、1.53倍.霾期SOC/OC值为0.43,略低于沙尘期,表明霾期SOC生成受到抑制.     

Highly efficient and selective removal of low-concentration antibiotics from aqueous solution by regenerable Mg(OH)2

The prevalent presence of fluoroquinolone antibiotics in aquatic environments has attracted considerable attention because of their harmful effects on humans and the ecological environment. Magnesium hydroxide nanocrystals were found to act as a simple and effective adsorbent to remove low-concentration ciprofloxacin (CIP) in aqueous solution. The as-prepared Mg(OH)₂ nanocrystals exhibited excellent CIP adsorption performance and high selectivity toward CIP molecules compared with other antibiotics or aromatics, e.g., norfloxacin (NOR) and eosin B (EB). The adsorbent showed pH-dependent adsorption, indicating that the adsorption process is probably dominated by an electrostatic interaction mechanism. In addition, structural analysis of the adsorbent indicated that coordination and hydrogen bonding between CIP and Mg(OH)₂ nanocrystal might also be involved in the adsorption process. Moreover, the adsorbent could be easily recovered by pyrolysis and hydration without significant reduction of adsorption capacity. The superior adsorption behavior of Mg(OH)₂ nanocrystal indicates that it may serve as a potential adsorbent material candidate for the selective removal of CIP from aquatic environments.     

Evaluation and impact factors of indoor and outdoor gas-phase nitrous acid under different environmental conditions

As an important indoor pollutant, nitrous acid (HONO) can contribute to the concentration of indoor OH radicals by photolysis via sunlight penetrating into indoor environments, thus affecting the indoor oxidizing capability. In order to investigate the concentration of indoor HONO and its impact factors, three different indoor environments and two different locations in urban and suburban areas were selected to monitor indoor and outdoor pollutants simultaneously, including HONO, NO, NO₂, nitrogen oxides (NO_x), O₃, and particle mass concentration. In general, the concentration of indoor HONO was higher than that outdoors. In the urban area, indoor HONO with high average concentration (7.10 ppbV) was well-correlated with the temperature. In the suburban area, the concentration of indoor HONO was only about 1-2 ppbV, and had a good correlation with indoor relative humidity. It was mainly attributed to the heterogeneous reaction of NO₂ on indoor surfaces. The sunlight penetrating into indoor environments from outside had a great influence on the concentration of indoor HONO, leading to a concentration of indoor HONO close to that outdoors.     

Enhanced photocatalytic activity of rGO/TiO2 for the decomposition of formaldehyde under visible light irradiation

Due to the low concentration of indoor air contaminants,photocatalytic technology shows low efficiency for indoor air purification.The application of TiO_2 for photocatalytic removal of formaldehyde is limited,because TiO_2 can only absorb ultraviolet(UV) light.Immobilization of TiO_2 nanoparticles on the surface of graphene can improve the visible light photocatalytic activity and the adsorption capacity.In this study,rGO(reduced graphene oxide)/TiO_2 was synthesized through a hydrothermal method using titanium tetrabutoxide and graphene oxide as precursors,and was used for the degradation of low concentration formaldehyde in indoor air under visible light illumination.Characterization of the crystalline structure and morphology of rGO/TiO_2 revealed that most GO was reduced to rGO during the hydrothermal treatment,and anatase TiO_2 nanoparticles(with particle size of 15–30 nm) were dispersed well on the surface of the rGO sheets.rGO/TiO_2 exhibited excellent photocatalytic activity for degradation of formaldehyde in indoor air and this can be attributed to the role of rGO,which can act as the electron sink and transporter for separating photo-generated electron–hole pairs through interfacial charge transfer.Furthermore,rGO could adsorb formaldehyde molecules from air to produce a high concentration of formaldehyde on the surface of rGO/TiO_2.Under visible light irradiation for 240 min,the concentration of formaldehyde could be reduced to 58.5 ppbV.rGO/TiO_2 showed excellent moisture-resistance behavior,and after five cycles,r GO/TiO_2 maintained high photocatalytic activity for the removal of formaldehyde(84.6%).This work suggests that the synthesized rGO/TiO_2 is a promising photocatalyst for indoor formaldehyde removal.