有关"致癌保鲜膜"问题的探讨

食品保鲜膜应用广泛,影响面大,"致癌保鲜膜"问题在我国掀起轩然大波;介绍食品保鲜膜的主要材质:聚乙烯(PE)、聚氯乙烯(PVC)、聚偏二氯乙烯(PVDC);分析哪些保鲜膜不安全;增塑剂DEHA是否致癌物,为什么有比较安全的PE保鲜膜,商家还要使用存在安全隐患的PVC保鲜膜;为什么有其他合法增塑剂不用,还要用违反国标的DEHA;不加增塑剂的保鲜膜是否绝对安全;保鲜膜能否放在微波炉里加热;有人不敢用保鲜膜,改用塑料袋、微波炉塑料容器了,是否保险.     

东莞市大岭山镇:打造现代生态新城创建全国环境优美乡镇

东临风光迤逦的松山湖,北靠同沙自然保护区,西南依大岭山森林公园,倚山傍湖,生成了大岭山镇的天生丽质.近年来,大岭山镇委、镇政府将建设"依山傍湖的现代生态新城"作为新时期战略目标,在"创建省卫生镇"等一系列工作上,获得喜人成绩.     

打破僵局

"我们拔了18吨,仍不见动静,请领导拿意见."4月13日,当河南油田井下作业二部副经理靳水生和工艺人员赶到L1256井场时,201修井队技术员范红禅立即向他们汇报拔钻解卡情况. "好,再拔拔看!"听到指令,司机汪佳柱启动30吨斜井作业机,一手扶离合器手柄,一手握刹把,脚踩油门,两眼紧盯指挥手势.作业机吼叫着,掐着油管的"脖子"使劲往上拽,那架势如同一场拔河比赛.压力器指针指向了18吨,油管还是一动不动.     

中俄界河黑龙江沿岸地区自然保护区建设和管理研究

随着生产力水平的不断提高和世界经济一体化趋势的快速发展,国际河流已成为有关国家开发的热点,国际河流的生态保护与生态安全是国家维护自身生态安全的前沿.界河--黑龙江流域可持续发展,对边境地区的稳定.防止流域生态退化和保护黑龙江流域森林、黑土地、湿地等资源具有重要意义.界河沿岸地区的自然保护区在保护该地区的生态环境,生物多样性、生态系统功能和国土安全方面起到了非常重要的作用.文章介绍了界河沿岸地区自然保护区的发展状况以及数量、面积、类型、分布和管理等现状,分析了制约自然保护区发展的主要因素提出了因地制宜的建设该地区自然保护区的有效措施及发展方向.     

天津快速的经济发展造成的环境问题及具对策

直面冷峻的环境现状,每一个有理性与责任感的公民无不忧心如焚.蔽日的烟云、腥臭的污河、毒化的农田和振聋发聩的噪音一刻不歇地疯狂考验和鞭笞着人们从心灵到生理的忍耐极限.本文使用大量详实的数据还原出天津环保的真相,社会各界的高度关注、积极参与和成效卓著的努力让我们对天津山清水秀的明日充满了期待.     

浅析电子政务信息的定位及实践

2006年起,广西壮族自治区地震局把做好政务信息工作摆上了重要议事日程,安排了专人负责,落实了措施,落实了专项经费,政务信息工作发生了质的飞跃.特别是信息管理员制度和激励机制从根本上改观了政务信息往日的面貌.本文介绍了广西壮族自治区地震局电子政务信息工作在事业发展中的定位、主要做法、成效和经验,意在抛砖引玉,加强学习和交流.     

上海市交通干道空气中挥发性有机物冬季污染特征研究

2004年冬季对上海市交通干道附近空气中的挥发性有机物进行了连续6天的监测.采用GC-MS定性检出28种物质,芳香烃和烷烃分别占32%和25%.在检出物中有8种属于美国EPA优先控制的有毒有害物质.GC-FID定量表明,芳香烃中含量最高的是苯系物(BTEX)苯、甲苯、乙苯、二甲苯,其中甲苯浓度最高.苯系物的浓度与一氧化碳和二氧化氮的良好相关性说明苯系物的来源与机动车尾气密切相关,而且都受风速和车流量的影响.     

电石渣综合利用研究进展

详细介绍了电石渣在生产建材,治理环境污染,生产化工产品等方面的利用,并对它们在处理效果,创造的经济效益及实际应用过程中遇到的问题进行了分析.提出了一种处理电石渣的有效方法--生产具备高附加值的纳米碳酸钙,在实现经济效益的同时,还能创造良好的环境效益及社会效益.     

惯性(小小说)

每天的17:30分,我们乘坐的班车在下班号响后会准时驶出厂门,出了厂门的右侧有个站,这儿是机关干部的上车点. 由于班车从我们车间始发,近水楼台先得月,我便有了固定的座位,一个位于车尾,靠窗的单座.而每天经过厂门口停站时,总会上来一个人,站在我边上,伸出一只毛茸茸的手抓住扶手.从那一身将校呢的制服上,我了解到他是厂武装部长,姓王,今年初刚转业到我们厂工作.     

"难缠"意味着什么

一次,我国一家工厂想接一位德商的棉布袋订单.对方要求,棉布袋的材料必须是本色棉布,两面的图案须用6种颜色印刷,而且对袋子的尺寸和提手的针脚都作了严格的规定.德商没有当场与这家工厂的厂长签约,而是提出在做出符合标准的样品后,再谈今后的合作.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Intraspecific differences in effects of co-contamination of cadmium and

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p ＜ 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.     

Characteristics of indoor/outdoor PM2.5 and elemental components in generic urban, roadside and industrial plant areas of Guangzhou City, China

Quantitative information on mass concentrations and other characteristics, such as spatial distribution, seasonal variation, indoor/outdoor （I/O） ratio, correlations and sources, of indoor and outdoor PM2.5 and elemental components in Guangzhou City were provided. Mass concentration of PM2.5 and elemental components were determined by standard weight method and proton-induced X-ray emission （PIXE） method. 18 elements were detected, the results showed positive results. Average indoor and outdoor PM2.5 concentrations in nine sites were in the range of 67.7-74.5μg/m^3 for summer period, and 109.9-123.7 μg/m^3 for winter period, respectively. The sum of 18 elements average concentrations were 5362.6-5533.4 ng/m^3 for summer period, and 8416.8-8900.6 ng/m^3 for winter period, respectively. Average concentrations of PM2.5 and element components showed obvious spatial characteristic, that the concentrations in roadside area and in industrial plant area were higher than those in generic urban area. An obvious seasonal variation characteristic was found for PM2.5 and elemental components, that the concentrations in winter were higher than that in summer. The I/O ratio of PM2.5 and some elemental components presented larger than 1 sometimes. According to indoor/outdoor correlation of PM2.5 and element concentrations, it was found that there were often good relationships between indoor and outdoor concentrations. Enrichment factors were calculated to evaluate anthropogenic versus natural elements sources.     

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

Developing a Regional Open Space Strategy (ROSS) for Central Puget Sound,Washington State,USA

Ecosystem services provided by the landscapes of regions and cities are critical to human and environmental health, quality of life, environmental justice, biodiversity and climate mitigation and adaptation. In the Pacific Northwest region of the US, a team led by the University of Washington Green Futures Lab is working to identify, conserve and enhance regionally-significant landscapes and to evaluate their contributions as ecosystem or “open space” services. This paper outlines the goals and planning methods of the ongoing Regional Open Space Strategy for Central Puget Sound (ROSS) project, and the frameworks and processes being developed to evaluate ecosystem and open space services in order to inform and influence local and regional governance structures and decisions.     

Nitrogen cycling of atmosphere-plant-soil system in the typical Calamagrostis angustifolia wetland in the Sanjiang Plain, Northeast China

The nitrogen (N) distribution and cycling of atmosphere-plant-soil system in the typical meadow Calamagrostis angustifolia wetland (TMCW) and marsh meadow Calamagrostis angustifolia wetland (MMCW) in the Sanjiang plain were studied by a compartment model. The results showed that the N wet deposition amount was 0.757 gN/(m2·a), and total inorganic N (TIN) was the main body (0.640 gN/(m2·a)). The ammonia volatilization amounts of TMCW and MMCW soils in growing season were 0.635 and 0.687 gN/m2, and the denitrification gaseous lost amounts were 0.617 and 0.405 gN/m2, respectively. In plant subsystem, the N was mainly stored in root and litter. Soil organic N was the main N storage of the two plant-soil systems and the proportions of it were 93.98% and 92.16%, respectively. The calculation results of N turnovers among compartments of TMCW and MMCW showed that the uptake amounts of root were 23.02 and 28.18 gN/(m2·a) and the values of aboveground were 11.31 and 6.08 gN/(m2·a), the re-translocation amounts from aboveground to root were 5.96 and 2.70 gN/(m2·a), the translocation amounts from aboveground living body to litter were 5.35 and 3.38 gN/(m2·a), the translocation amounts from litter to soil were larger than 1.55 and 3.01 gN/(m2·a), the translocation amounts from root to soil were 14.90 and 13.17 gN/(m2·a), and the soil (0-15cm) N net mineralization amounts were 1.94 and 0.55 gN/(m2·a), respectively. The study of N balance indicated that the two plant-soil systems might be situated in the status of lacking N, and the status might induce the degradation of C. angustifolia wetland.     

三种含钙物质对土壤砷植物有效性的影响

综述含钙物质（生石灰（CaO）、熟石灰（Ca （OH）₂）及石灰石（CaCO₃））对土壤理化性质（pH值、有机质成分及其含量）、土壤微生物群落结构和As赋存形态及生物有效性的影响与机制,及其对植物As吸收积累和As耐性的影响与机制.综述内容可为准确理解含钙物质影响土壤As的生物有效性和植物对As吸收积累的过程机制,进而合理选择含钙物质调控土壤理化性质降低土壤As生物有效性及其生态环境风险提供理论依据和技术参考,对保障土壤种植安全和作物食品安全具有一定现实意义.     

Integrating mitigation and adaptation into climate and development policy: three research questions

The potential for developing synergies between climate change mitigation and adaptation has become a recent focus of both climate research and policy. Presumably the interest in synergies springs from the appeal of creating win–win situations by implementing a single climate policy option. However, institutional complexity, insufficient opportunities and uncertainty surrounding their efficiency and effectiveness present major challenges to the widespread development of synergies. There are also increasing calls for research to define the optimal mix of mitigation and adaptation. These calls are based on the misguided assumption that there is one single optimal mix of adaptation and mitigation options for all possible scenarios of climate and socio-economic change, notwithstanding uncertainty and irrespective of the diversity of values and preferences in society. In the face of current uncertainty, research is needed to provide guidance on how to develop a socially and economically justifiable mix of mitigation, adaptation and development policy, as well as on which elements would be part of such a mix. Moreover, research is needed to establish the conditions under which the process of mainstreaming can be most effective. Rather than actually developing and implementing specific mitigation and adaptation options, the objective of climate policy should be to facilitate such development and implementation as part of sectoral policies. Finally, analysis needs to focus on the optimal use and expected effectiveness of financial instruments, taking into account the mutual effects between these instruments on the one hand, and national and international sectoral investments and official development assistance on the other.     

Alterations of organ histopathology and metallolhionein mRNA expression in silver barb, Puntius gonionotus during subchronic cadmium exposure

Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.     

新型杂化材料钝化修复镉铅复合污染土壤的效应与机制研究

采用盆栽实验,研究了新型杂化材料及其与磷酸盐复配使用对镉铅复合污染土壤的钝化修复效果,并通过重金属形态分析、吸附平衡实验以及X射线光电子能谱(XPS)探讨了杂化材料钝化修复重金属污染土壤的机制.结果表明,杂化材料单一处理对油菜生长没有明显的促进作用,而杂化材料与磷酸盐复合处理则能显著提高油菜地上部和根部生物量,分别比对...