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101.
黄荆自然保护区植物区系的初步研究   总被引:3,自引:0,他引:3  
黄荆自然保护区地处四川盆地与云贵高原的过渡地带,地带性植被为亚热带偏湿性常绿阔叶林,有种子植物165科745属1521种,其中裸子植物9科19属24种,被子植物156科726属1497种.该区特殊的自然条件和复杂的地质构造,使其成为多种植物地理成分的汇集地,并成为我国乃至全世界亚热带(同纬度)地区保存较好的常绿阔叶林植被群落,具有极高的研究价值和生态价值.根据近年来的科学考察,认为黄荆自然保护区植物区系的种类丰富、珍稀特有植物较多、起源古老、区系成分复杂,显示出多方植物交汇的特点.  相似文献   
102.
李艳丰 《安全》2019,40(6):72-75,79
本文根据采油厂生产过程风险特点,以生产单元为对象,通过建立全员参与的HSE监督检查体系,实现对采油厂HSE监督检查标准的统一规范,利用开发的HSE监督检查信息集成平台,创建完成采油厂HSE监督检查管理系统。在大庆油田第五采油厂的应用实践显示,其能为采油厂带来巨大的风险管理效益,是全面落实直线与属地HSE责任的有效载体。对于采油厂有效实施HSE监督检查具有重大意义,是HSE管理制度的一种创新。  相似文献   
103.
The causes of species rarity are of critical concern because of the high extinction risk associated with rarity. Studies examining individual rare species have limited generality, whereas trait‐based approaches offer a means to identify functional causes of rarity that can be applied to communities with disparate species pools. Differences in functional traits between rare and common species may be indicative of the functional causes of species rarity and may therefore be useful in crafting species conservation strategies. However, there is a conspicuous lack of studies comparing the functional traits of rare species and co‐occurring common species. We measured 18 important functional traits for 19 rare and 134 common understory plant species from North Carolina's Sandhills region and compared their trait distributions to determine whether there are significant functional differences that may explain species rarity. Flowering, fire, and tissue‐chemistry traits differed significantly between rare and common, co‐occurring species. Differences in specific traits suggest that fire suppression has driven rarity in this system and that changes to the timing and severity of prescribed fire may improve conservation success. Our method provides a useful tool to prioritize conservation efforts in other systems based on the likelihood that rare species are functionally capable of persisting.  相似文献   
104.
We designed 3 image‐based field guides to tropical forest plant species in Ghana, Grenada, and Cameroon and tested them with 1095 local residents and 20 botanists in the United Kingdom. We compared users’ identification accuracy with different image formats, including drawings, specimen photos, living plant photos, and paintings. We compared users’ accuracy with the guides to their accuracy with only their prior knowledge of the flora. We asked respondents to score each format for usability, beauty, and how much they would pay for it. Prior knowledge of plant names was generally low (<22%). With a few exceptions, identification accuracy did not differ significantly among image formats. In Cameroon, users identifying sterile Cola species achieved 46–56% accuracy across formats; identification was most accurate with living plant photos. Botanists in the United Kingdom accurately identified 82–93% of the same Cameroonian species; identification was most accurate with specimens. In Grenada, users accurately identified 74–82% of plants; drawings yielded significantly less accurate identifications than paintings and photos of living plants. In Ghana, users accurately identified 85% of plants. Digital color photos of living plants ranked high for beauty, usability, and what users would pay. Black and white drawings ranked low. Our results show the potential and limitations of the use of field guides and nonspecialists to identify plants, for example, in conservation applications. We recommend authors of plant field guides use the cheapest or easiest illustration format because image type had limited bearing on accuracy; match the type of illustration to the most likely use of the guide for slight improvements in accuracy; avoid black and white formats unless the audience is experienced at interpreting illustrations or keeping costs low is imperative; discourage false‐positive identifications, which were common; and encourage users to ask an expert or use a herbarium for groups that are difficult to identify. Pruebas Empíricas de Guías de Campo de Plantas Hawthorne, Cable & Marshall  相似文献   
105.
介绍了燃煤电厂超低排放气态污染物监测系统的采样系统和分析单元,分析了其各自的优缺点。对稀释抽取式、冷干抽取式和热湿抽取式3种采样方法,以及非分散红外吸收法(NDIR)、非分散紫外吸收法(NDUV)、紫外差分吸收法(DOAS)、紫外荧光法(UVF)和化学发光法(CL)5种分析方法进行对比。结果表明,冷干抽取式+紫外差分法以及稀释抽取式+紫外荧光法+化学发光法可以较好地符合燃煤电厂超低排放监测的要求。  相似文献   
106.
分析了我国火电厂自行监测的现状及存在的问题,包括监测指标不全、监测频次不足、监测点位代表性不够、信息公开不规范等。从监测方案和信息记录2个方面,针对废气、废水、厂界噪声、周边环境质量等的监测点位、监测指标和监测频次,以及监测信息、生产和污染治理设施运行状况、工业固体废物的记录要求,提出了相应的技术建议。  相似文献   
107.
选取上海市7家未安装气-气换热器的国控燃煤电厂作为研究对象,从煤质、除尘器、脱硫协同脱除作用以及锅炉工况负荷等方面探讨对颗粒物浓度排放系数 K值产生的影响,得出上述因素通过改变脱硫进口颗粒物浓度值影响 K值,当脱硫进口颗粒物浓度较低、波动范围较小时,其 K值也维持相对稳定的状态;当脱硫进口颗粒物浓度较高、波动范围较大时,其 K值也会发生较大的变化等结论。  相似文献   
108.
工业内窥镜是电站锅炉内部检验中不可或缺的设备,主要用来对集箱、减温器、受热面管等内部人眼无法观察到的地方进行检验,从而确定承压部件内部是否存在严重影响锅炉安全运行的缺陷.本文通过对锅炉内窥实例进行分析和总结,阐述内窥镜检查在锅炉内检中的重要性并给相关工作人员提供借鉴与参考.  相似文献   
109.
Valuable chemicals can be separated from agricultural residues by chemical or thermochemical processes. The application of pyrolysis has already been demonstrated as an efficient means to produce a liquid with a high concentration of desired product. The objective of this study was to apply an insect and microorganism bioassay-guided approach to separate and isolate pesticidal compounds from bio-oil produced through biomass pyrolysis. Tobacco leaf (Nicotianata bacum), tomato plant (Solanum lycopersicum), and spent coffee (Coffea arabica) grounds were pyrolyzed at 10°C/min from ambient to 565°C using the mechanically fluidized reactor (MFR). With one-dimensional (1D) MFR pyrolysis, the composition of the product vapors varied as the reactor temperature was raised allowing for the selection of the temperature range that corresponds to vapors with a high concentration of pesticidal properties. Further product separation was performed in a fractional condensation train, or 2D MFR pyrolysis, thus allowing for the separation of vapor components according to their condensation temperature. The 300–400°C tobacco and tomato bio-oil cuts from the 1D MFR showed the highest insecticidal and anti-microbial activity compared to the other bio-oil cuts. The 300–350 and 350–400°C bio-oil cuts produced by 2D MFR had the highest insecticidal activity when the bio-oil was collected from the 210°C condenser. The tobacco and tomato bio-oil had similar insecticidal activity (LC50 of 2.1 and 2.2 mg/mL) when the bio-oil was collected in the 210°C condenser from the 300–350°C reactor temperature gases. The 2D MFR does concentrate the pesticidal products compared to the 1D MFR and thus can reduce the need for further separation steps such as solvent extraction.  相似文献   
110.
选取我国 HJ-1 B卫星红外相机为遥感数据源,在介绍了温排水卫星遥感监测的技术流程和基本原理之后,重点论述了海表温度反演的算法和基准温度提取的基本原则。以2013年1月17日大亚湾核电站和2013年5月22日田湾核电站2景 HJ-1 B红外相机数据为应用实例,说明了卫星遥感监测可作为开展核电站温排水影响监测与热污染评价的首选技术方向和主要监测手段,阐述了其在核电站温排水影响后评估中的作用和意义。  相似文献   
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