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231.
辽宁省背景地区降水化学特征及其与大气传输的关系   总被引:7,自引:4,他引:3  
为了解辽宁省背景地区降水化学特征及其与大气传输的关系,于2007年2月─2008年1月在辽中县水文监测站进行了降水化学特征观测,测量项目包括降水pH,电导率和离子浓度. 观测期间降水pH为3.4~7.3,降水量加权平均值为4.6,整体呈酸性. 降水中主要阴离子为SO42-和NO3-,浓度分别为154.3和53.4 μeq/L,二者占阴离子总量的76.8%; 主要阳离子为NH4+和Ca2+,浓度分别为124.6和89.2 μeq/L,占阳离子总量的70.6%. 利用后向气流轨迹分析了降水气团来源对降水化学的影响,结果表明:在辽宁省及周边地区的局地气团影响下,降水中离子浓度最高;而在起源于东亚地区,经朝鲜半岛到达的南-东南气团影响下,降水次数虽最多,但离子浓度最低.   相似文献   
232.
利用废弃物煅烧水泥时重金属Pb、Cd的逸放污染   总被引:1,自引:1,他引:0  
利用废弃物作为代替原料煅烧水泥已广泛应用于水泥生产,但其带来的环境污染问题不容忽视。以利用废弃物生产水泥的厂家为研究对象,采用原子吸收分光光度法检测所采集样品中重金属Pb、Cd的含量,对水泥生产过程中重金属Pb、Cd的逸放及其对周围土壤的污染进行研究。研究结果表明:利用废弃物煅烧水泥的过程中,重金属Pb、Cd的逸放率很高,其中立窑的Pb、Cd逸放率高达84%~90%。湿法回转窑的Pb、Cd逸放率达到63%~74%;在水泥厂上下风向500m、1000m和2000m处采集土壤样品,工厂周围的土壤均已受到不同程度的重金属污染,位于工厂下风向的土壤受到的污染更为严重,距离工厂500m处土壤中重金属Pb、Cd的含量均超过了国家标准的最大限量;对几家工厂员工的头发进行随机取样,头发样品中Pb含量均超过正常限量:  相似文献   
233.
This study recruited 14 industrial workers to examine the effects of carrying handles, postures, materials and distances on maximum acceptable weights of carrying (MAWC), and resulting heart rate and body rating of perceived exertion (RPE) for a 20 min intensive carrying task. This study showed that MAWC of carrying with bar handles, carrying with hands-and-body posture, solid materials and 4?m distance were significantly higher than that of carrying with groove handles, carrying with hands posture, liquid materials and 8?m distance, respectively. The resulting heart rates while carrying MAWCs of groove handles, hands-and-body carrying posture, solid materials and 4?m distance were lower than the resulting heart rates while carrying MAWCs of bar handles, hands carrying posture, liquid materials and 8?m distance, respectively. Most pair levels of independent variables resulted in similar body's RPEs except for the pair levels of carrying distance.  相似文献   
234.
The number of manufactured aircraft has been continuously increasing worldwide because of the high demand for airline transportation. During manufacturing, many advanced materials and devices are used to build various sizes and shapes of aircraft. However, most of these materials and devices require considerable energy and labor to produce, so reusing these at any life stage of the aircraft offers many economic and environmental benefits, and is considered lucrative and environmentally responsible. Several recyclable materials—composites, metals and alloys, wires, wood, paper, plastics, electronics, and avionics—emerge as waste streams during the manufacturing of aircraft. Many aircraft companies have been recycling these materials to remanufacture aircraft parts or other products for more sustainable production. In the present study, we evaluated the recycling efforts of local aircraft companies in Wichita, KS. These efforts were considered in terms of recycling efficiency/rate and environmental benefits. These included cradle-to-gate (CTG) life-cycle inventory analysis of the materials, carbon dioxide emissions, virgin material replacement with recycled materials, and natural resources usage. Our findings show that there exists a significant potential for contributions to sustainability as well as environmental and health benefits in the region from recycling by aircraft manufacturing plants.  相似文献   
235.
Abstract

The forests of Nepal, which in the past were at least nominally under the direct control of the state, are today increasingly entrusted to local people in the name of community forestry (CF). CF is considered a successful endeavour in managing forest resources, conserving biodiversity and supplying people with basic economic needs. In order to assess to what extent the two goals of biodiversity conservation and meeting economic needs of people have been integrated through CF, four community forestry user groups (CFUGs) were studied in the Mid-hills ecological zone. Based on a participatory survey and a critical review of the statutes and operational plans of these CFUGs, it was found that integration of biodiversity conservation was still insufficient, and that improvements in the policy and management regimes of CF are necessary to achieve a balance between biodiversity conservation and economic use of the forest resources.  相似文献   
236.
A sintering technology for preparing porous materials from sea bottom sediments was developed for use in water purification. The purpose of the present study was to develop methods for converting the sea bottom sediments dredged from Ago Bay into value-added recycled products. The sintered products fabricated at 400℃ were found to be very effective adsorbents for the removal of heavy metals.  相似文献   
237.
再生塑料粉煤灰复合材料井盖   总被引:1,自引:0,他引:1  
将废塑料、粉煤灰、农作物秸杆等固体废弃物通过自主创新技术成功地制备了市政工程制品:井盖、井箅等。具有抗压、抗冲击性能优良;成本低;环境友好;美观;安全等特性。  相似文献   
238.
聚苯乙烯发泡塑料(EPS)作为缓冲包装的内衬件广泛用于电子产品的内包装,但其所带来的白色污染问题也日益严峻。研究以再生资源(废纸)为原料,生产产品内衬包装物——纸浆模塑缓冲材,并使其产业化,以替代发泡塑料包装物,改变发泡塑料包装物难降解所带来的污染和危害,并实现“废弃物—产品”的资源循环利用。  相似文献   
239.
港口后勤区域是港口功能的重要拓展空间,已成为影响港口物流运营效率的重要因素。运用ARCVIEW网络分析模块,从交通运输成本的角度,通过分析港口后勤区域候选点到直接腹地、间接腹地的运输成本,以及各候选点的综合运输成本进而对外高桥港口后勤区域区位进行研究。研究表明:外高桥保税物流园区至港区的运输成本系数为0.381 4、0.275 9、0.319 5和0.211 8,整体处于较高水平;到直接腹地的运输成本系数分别为1.107 93、1.136 49、1.085 24和1.109 76,处于偏低水平;到间接腹地的运输成本系数分别为0.874 5、0.935、0.825 4和0.874,整体处于中等水平;到腹地的运输成本系数分别为0.944 5、0.995 4、0.903 4和0.944 7,整体处于中等偏弱地位。外高桥保税物流园区到港区和腹地的综合运输成本系数分别为0.663、0.635 7、0.611 4和0.578 2,综合区位条件较好。今后,随着外高桥港区货运量的增加,保税物流园区应该向东南方向拓展。  相似文献   
240.
Disassembly has been widely accepted as a disadvantageous end-of-life activity, but with increasing pressures from directives, such as waste on electrical and electronic equipment, and with increasing pressures to become sustainable disassembly is becoming necessary. Current disassembly methods, including both manual and automated disassembly, need improvements to meet this necessity. This paper will introduce the improvements needed and suggest through literature the validity of active disassembly (AD) to provide these improvements. Past and current research will also be considered to provide a future path for AD. This future path for AD will consider a collaborative effort to solve problems with materials, environmental triggers and costs seen with AD.  相似文献   
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