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51.
关于军用装备质量控制过程中的几点体会   总被引:1,自引:0,他引:1  
那建桥 《环境技术》2009,27(4):33-34,48
本文主要简述了某军用装备型号设备在质量控制过程中注意的几个重要方面,并对具体管理工,作中的要求展开了讨论。  相似文献   
52.
Abstract: The influence of landscape matrix on functional connectivity has been clearly established. Now methods to assess the effects of different land uses on species’ movements are needed because current methods are often biased. The use of physiological parameters as indicators of the level of resistance to animal movement associated with different land uses (i.e., matrix resistance) could provide estimates of energetic costs and risks to animals migrating through the matrix. To assess whether corticosterone levels indicate matrix resistance, we conducted experiments on substrate choice and measured levels of corticosterone before and after exposure of toads (Bufo bufo) to 3 common substrates (ploughed soil, meadow, and forest litter). We expected matrix resistance and hormone levels to increase from forest litter (habitat of the toad) to meadows to ploughed soil. Adult toads had higher corticosterone levels on ploughed soil than on forest litter or meadow substrates. Hormone levels did not differ between forest litter and meadow. Toads avoided moving onto ploughed soil. Corticosterone levels in juvenile toads were not related to substrate type; however, hormone levels decreased as humidity increased. Juveniles, unlike adults, did not avoid moving over ploughed soil. The difference in responses between adult and juvenile toads may have been due to differences in experimental design (for juveniles, entire body used to measure corticosterone concentration; for adults, saliva alone); differences in the scale of sensory perception of the substrate (juveniles are much smaller than adults); or differences in cognitive processes between adult and juvenile toads. Adults probably had experience with different substrate types, whereas juveniles first emerging from the water probably did not. As a consequence, arable lands could act as ecological traps for juvenile toads.  相似文献   
53.
Abstract:  A World Conservation Union (IUCN) regional red list is an objective assessment of regional extinction risk and is not the same as a list of conservation priority species. Recent research reveals the widespread, but incorrect, assumption that IUCN Red List categories represent a hierarchical list of priorities for conservation action. We developed a simple eight-step priority-setting process and applied it to the conservation of bees in Ireland. Our model is based on the national red list but also considers the global significance of the national population; the conservation status at global, continental, and regional levels; key biological, economic, and societal factors; and is compatible with existing conservation agreements and legislation. Throughout Ireland, almost one-third of the bee fauna is threatened (30 of 100 species), but our methodology resulted in a reduced list of only 17 priority species. We did not use the priority species list to broadly categorize species to the conservation action required; instead, we indicated the individual action required for all threatened, near-threatened, and data-deficient species on the national red list based on the IUCN's conservation-actions template file. Priority species lists will strongly influence prioritization of conservation actions at national levels, but action should not be exclusive to listed species. In addition, all species on this list will not necessarily require immediate action. Our method is transparent, reproducible, and readily applicable to other taxa and regions.  相似文献   
54.
UV-vis光照下唑类抗菌药氟康唑的光化学反应类型   总被引:1,自引:1,他引:0  
以唑类抗菌药氟康唑为模型化合物,考察了其在纯水中的光降解动力学和光化学反应类型,发现模拟日光(λ>290nm)照射下氟康唑未发生光解,在UV-vis(λ>200 nm)光照下,氟康唑发生了光降解并服从准一级反应动力学.采用活性氧物种猝灭实验和竞争动力学方法,研究发现氟康唑发生了直接光解和·OH参与的自敏化光解,氟康唑与.OH的反应速率常数为(5.95±0.58)×109L·(mol·s)-1,表层水体中相应的半减期为(32.41±3.16)h·通过鉴定光解产物,得知氟康唑发生了脱氟、光致水解、光氧化等光化学反应.  相似文献   
55.
娜仁  李康玮  万伦来  杨峻 《环境科学研究》2019,32(12):2048-2056
为研究煤炭资源型城市煤炭开采与生态系统服务的耦合协调发展态势,以我国高潜水位煤炭资源型城市——淮北市为研究对象,在分析煤炭开采与生态系统服务耦合作用机理的基础上,采用基于灰色关联分析的关联度模型和耦合度模型,揭示了1990-2016年该地区煤炭开采与生态系统服务耦合度的时序变化规律.结果表明:①淮北市煤炭开采与生态系统服务两个系统指标间的关联度均在0.447 5~0.553 4之间,其中,煤炭开采对生态系统服务的胁迫作用主要是水资源破坏,而生态系统服务对煤炭开采的约束作用主要来自调节服务.②淮北市煤炭开采与生态系统服务耦合度表现为1990-1999年逐渐降低、2000-2008年不断升高、2009年之后又呈下降趋势,反映了该地区煤炭开采与生态系统之间的矛盾趋于缓和,出现了统筹协调发展的大好形势.研究显示,1990-2016年淮北市煤炭开采与生态系统服务总体上呈中等耦合态势,耦合度时序变化总体上呈"倒N"型变化特征,今后需继续推进资源型城市转型建设,加大生态治理力度,以保持统筹协调发展态势.   相似文献   
56.
该研究在中国第27次南极科考(27th CHINARE)度夏期间(2009.11-2010.01)在长城湾潮间带采集了11种常见生物样品,通过GC-MS检测了生物体内的16种常见多环芳烃(polycyclic aromatic hydrocarbons,PAHs)的含量,根据检测数据分析亚南极地区海域潮间带生物群落中的PAHs在潮间带生物群落中的含量状况,初步探讨该地区PAHs的潜在来源。ΣPAHs为136.97~649.31(ng/g干重,下同),萘、菲、蒽、芴等低环芳烃所有生物样品均检出包括萘、菲、蒽、芴等常见低环芳烃,苯并芘(a)、茚苯(1,2,3-cd)芘、二苯并(a,h)蒽、苯并(g,h,i)芘少数样品苯并芘(a)、茚苯(1,2,3-cd)芘、二苯并(a,h)蒽、苯并(g,h,i)芘未检出,ΣPAHs为136.97~649.31(ng/g干重,下同),低环芳烃占57.45%~86.27%,Phe和Nap是最主要的2种PAHs。采用比值法分析该地区PAHs组成可知该地区PAHs主要来自柴油燃烧和柴油泄漏。对不同生物体内的16种多环芳烃组成比例进行比较,可以发现长城湾潮间带生物群落具有相似的PAHs组成比例。  相似文献   
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