被关在笼子里的感觉是什么

“收获真不小呀！”我赶紧叫爸爸出去买了一个鸟笼子,高兴地把捉到的小麻雀放了进去。真没想到,到公园来玩儿,还能捉到麻雀！看这个小家伙,进了笼子,一个劲儿地又蹦又跳,小翅膀一扇一扇的。肯定是想逃出去。这可不行,你走了,谁和我玩儿呢？ 　　到了家,我找来些小米,放到小麻雀的“碗”里,还给它的“杯子”里加了一些干净的水。这样你就不会饿也不会渴了,我轻轻地对它说。小家伙真奇怪,不吃也不喝,只是瞪着黑亮的小眼睛,使劲儿往外撞。实在累了,就缩着身子,躲在笼子的角落里。 　　吃完饭,我看了一会儿电视,又逗了一会儿…     

关于荒漠化地区可持续发展的几点思考——以北方沙漠化地区为例

荒漠化的发生、发展和逆转过程蕴涵着丰富的生态学、社会学和经济学原理。本文首先提出了荒漠化地区人地关系研究的技术路线,即现状诊断－－演变历程－－矛盾与冲突分析－－协调性分析－－调控与管理;继之以北方沙漠化地区为例,对路线涉及的具体内容加以简要分析;在此基础上,对如何协调人地关系提出建议。     

适应信息化发展要求,努力实现PPE标准制修订科学化和正规化管理——PPE标准化技术委员会标准全程控制系统介绍

PPE标准化技术委员会标准全程控制系统是基于互联网的PPE信息管理系统平台。该系统采用便捷的B/S架构,利用先进的计算机信息技术,将标准制修订的全过程集成到一个系统中,使标准的制修订流程实现了全程自动化管理,极大地方便了标准制修订各个环节的工作,提高了PPE标准化工作的管理水平,促进了整个行业信息化的发展,确保了国家标准计划按期高水平的完成。     

The non-target organism Caenorhabditis elegans withstands the impact of sulfamethoxazole

The widespread usage of antibiotics in agriculture leads to releases into the environment, but there is insufficient knowledge of the side-effects on non-target organisms. Therefore, we investigated the effects of the sulfonamide-antibiotic sulfamethoxazole (SMX) on Caenorhabditis elegans at phenotypic, biochemical and molecular biological levels. Multiple endpoints, including life history traits, thermal stress resistance and lipid peroxidation, as well as gene expression profiles, were determined after exposure of the nematodes to SMX. In contrast to expectations, SMX prolonged the lifespan and increased both the body size and pharynx pumping rate. On the other hand, SMX delayed reproductive timing and caused lipid peroxidation. The total number of offspring and thermal stress resistance were unaffected. The up-regulation of hsp-16.1 indicated stress in general and the increased lipid peroxidation oxidative stress in particular. This oxidative stress indicated that mitohormesis was the likely cause of the longevity and that enhanced pumping frequency was probably the reason for the increased growth. The sole adverse effect was delayed initial reproduction. This delay, however, can be crucial for r-strategists, such as the bacterivorous model animal used, in sustaining their populations in the environment in the presence of predators. Bacterivorous animals, in turn, are essential to maintaining nutrient recycling via the microbial loop.     

桂林市菜地土壤和蔬菜砷含量调查与健康风险评估

通过对桂林市蔬菜和菜地土壤中砷含量状况的调查,研究了蔬菜和菜地土壤中的砷含量、富集特征及对人体的健康风险,并筛选出抗砷污染能力强的蔬菜品种.本研究在桂林市13个县区蔬菜种植基地和蔬菜批发市场共采集71种566个蔬菜样品,160个相对应菜地的土壤样品和32个背景土壤样品.研究发现,与背景土壤相比,桂林市菜地土壤没有明显的砷积累(平均积累指数为0.839),砷含量范围、算术均值、几何均值分别为5.55~132、23.4、21.4 mg·kg-1.蔬菜(鲜重)总砷含量范围、中值和几何平均值分别为5.34~49.7、24.0、22.2 mg·kg-1,均未超标,且叶菜类蔬菜中的砷含量高于根茎类和瓜果类.根据蔬菜砷富集系数的高低用层级聚类法分析,结果表明,西红柿、油麦菜、胡萝卜、生菜等18种蔬菜的抗砷污染能力最强.桂林市居民通过消费蔬菜的人均总砷摄入量为2.54μg·d-1,蔬菜消费只占总砷摄入量的7.07%左右,因此,对于大多数居民而言不存在明显的健康风险.     

个体防护装备创新研制探析

个体防护装备是保障从业者人身安全的重要保护装备,研制性能优异的保护装备、装具和防护用品,可保障从业人员的作业安全。如何更好的感知危险因素,预防安全事故的发生,实现从业人员快速撤离的主动式个体防护技术及装备将成为研究重点。本文提出主动式个体防护装备的创新研制需立足危险因素及作业人员这两个关键环节,实现危险因素信息与作业人员信息的实时感知、高效互通、快速预警与处置,进而实现个体防护装备从被动防护到主动防护的深刻变革。     

尾砂库溃坝对大环江沉积物中重金属的影响

为研究2001年特大洪水导致的北山铅锌矿尾砂库溃坝对大环江沉积物中重金属含量的影响及其潜在的生态风险,沿大环江自北向南设置了21个样点,共采集沉积物样品77个;分别采用SQG(沉积物质量基准)、PLC(污染负荷指数)和Hankson潜在生态风险指数法,对尾砂库下方大环江沉积物表层及剖面中As、Pb、Cd、Cu和Zn 5种重金属进行了分析和评价. 结果表明:大环江沉积物剖面pH平均值在2.09~7.51之间,其中38.1%的采样点土壤pH低于环江县背景值上限;表层(0~25 cm)沉积物中w(As)、w(Pb)、w(Cd)、w(Cu)和w(Zn)的平均值分别是环江谷地土壤平均值的3.2、20.0、59.2、2.1、17.0倍. 沉积物剖面的重金属质量分数分布主要有自上而下先降后升或先升后降2类规律,w(As)与w(Pb)、w(Cu),w(Pb)与w(Cu)、w(Zn),w(Cd)与w(Zn)均呈显著相关. 根据SQG法评估结果,大环江沉积物剖面首层(0~22 cm)w(As)、w(Pb)、w(Cd)和w(Zn)已对水域生物产生严重影响;大环江流域的PLI为2.57,属于极强污染;以环江县土壤背景值为参比值的Hankson潜在生态风险指数分析结果显示,大环江表层沉积物呈现强~极强的生态风险,5种重金属的污染程度为Cd＞Pb＞As＞Zn＞Cu. 尾砂库溃坝导致大环江沉积物中重金属质量分数陡然升高且难以恢复.      

Effects of ambient temperature on regulated gaseous and particulate emissions from gasoline-, E10- and M15-fueled vehicles

• Emissions from two sedans were tested with gasoline, E10 and M15 at 30°C and -7°C. • As the temperature decreased, the PM, PN and BC emissions increased with all fuels. • Particulate emissions with E10 and M15 were more sensitive to the temperature. • The PN and BC generated during cold start-up dominated those over the WLTC. Ambient temperature has substantial impacts on vehicle emissions, but the impacts may differ between traditional and alcohol gasolines. The objective of this study was to investigate the effects of temperature on gaseous and particulate emissions with both traditional and alcohol gasoline. Regulated gaseous, particle mass (PM), particle number (PN) and black carbon (BC) emissions from typical passenger vehicles were separately quantified with gasoline, E10 (10% ethanol and 90% gasoline by volume) and M15 (15% methanol and 85% gasoline by volume) at both 30°C and -7°C. The particulate emissions with all fuels increased significantly with decreased temperature. The PM emissions with E10 were only 48.0%–50.7% of those with gasoline at 30°C but increased to 59.2%-79.4% at -7°C. The PM emissions with M15 were comparable to those with gasoline at 30°C, but at -7°C, the average PM emissions were higher than those with gasoline. The variation trend of PN emissions was similar to that of PM emissions with changes in the fuel and temperature. At 30°C, the BC emissions were lower with E10 and M15 than with gasoline in most cases, but E10 and M15 might emit more BC than gasoline at -7°C, especially M15. The results of the transient PN and BC emission rates show that particulate emissions were dominated mainly by those emitted during the cold-start moment. Overall, the particulate emissions with E10 and M15 were more easily affected by ambient temperature, and the advantages of E10 and M15 in controlling particulate emissions declined as the ambient temperature decreased.     

土壤重金属污染来源及修复技术研究

土壤是生态环境的重要组成部分,与人类的生存和健康密切相关。土壤重金属污染问题是环境和土壤科学研究者关注的热点问题。对土壤重金属污染物来源的鉴别是准确、有效控制和治理污染源的前提。根据近年来国内外对土壤重金属污染的相关研究报道,综述了土壤中污染物的工业、农业和交通因子三大主要来源。目前重金属污染土壤修复主要采用工程技术、物理化学技术和植物修复技术。在此就修复技术的原理、适用范围以及研究现状与发展动态等方面进行了综述与分析。     

采用蒸气吹脱解附法对废弃活性炭回收醋酸丁酯的试验研究

试验用废弃活性炭做回收醋酸丁酯的研究,采用蒸气吹脱解附法,设计制作活性炭解吸塔,考察蒸气用量对活性炭解吸的影响,同时确定最佳解吸时间及可回收的丁酯量,并探讨回收醋酸丁酯的同时能够再生活性炭的试验条件。