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31.
FHD型森林地下火探测仪为最新研制的一种光机电一体化的便携式探测设备,采用红外探测技术原理,借助红外焦平面成像器件、可见光摄像器件采集目标图像,利用图像处理技术完成对目标视频图像的获取、显示、温度分析处理及存储过程。它集成了红外与可见光两种模式,两种模型的简单切换有利于辨识目标并可对热像的中心区域进行测温显示。该设备操作界面简单快捷,图片存储方便、容量大,可用于户外多热源连续监测作业。  相似文献   
32.
急性毒性藻红外测试中敏感藻的确定方法   总被引:1,自引:1,他引:0  
敏感藻是指在急性毒性藻红外测试中对毒物响应的温差大、时间快、种类多、剂量低的特殊藻类.自然藻中是否存在敏感藻以及如何确定,是建立藻红外测试法的关键.为此,开展了敏感藻确定方法的探索性研究.试验用8种藻,重金属、有机毒物、农药各10种进行测试分析,结果表明:短线脆杆藻(Fragilaria brevistriata)对重金属、羊角月牙藻(Selenastrum capricornutum)对有机毒物、纤细裸藻(Euglena gracilis)对除草剂和杀虫剂、水华鱼腥藻(Anabaena flos-aquae)对杀菌剂的平均绝对温差分别为0.21℃、0.27℃、0.19~0.20℃、0.20℃,分别高出各自的总均温差0.07℃、0.15℃、0.07℃、0.08℃;4种藻的平均响应时间1.5~7.0min,较好响应药品的响应率≥80%;发光细菌对部分药品的灵敏度在0.07~50.0mg·L-1,而4种藻对相同药品的灵敏度在0.01~7.0mg·L-1.根据敏感藻定义和试验结果,确定短线脆杆藻、羊角月牙藻、纤细裸藻、水华鱼腥藻分别为重金属、有机毒物、除草剂和杀虫剂、杀菌剂的敏感藻.  相似文献   
33.
Green source Ep was extracted from marine alga waste. The molecule model structure of Ep was studied and constructed. PAC-Ep coagulation system improves the efficiency of removal efficiency. Synergistic effects between NPs and HA make a big difference to enhance efficiency. Mechanism is charge neutralization, hydrogen bonding and adsorbing-complexing Enteromorpha polysaccharide (Ep) extracted from alga a novel green coagulant aid for nanoparticles (NPs) and heavy metal ions removal and the structure of EP was intensively studied in this study. The integration of Ep with polyaluminum chloride (PAC-Ep) coagulants exhibited higher coagulation performance than that of the polyaluminum chloride (PAC) because of the negatively charged NPs suspension and humic aid (HA) solution. Significant high removal efficiencies of dissolved organic matter (94.1%), turbidity (99.3%) and Zn ions (69.3%) were achieved by the PAC-Ep coagulants. The dual-coagulation properties of PAC-Ep for different pollutants was based on multiple mechanisms, including (i) Al3+ charge neutralization; (ii) hydroxy aluminum hydroxyl bridging formed polynuclearhydroxy complexes bridge and sweep colloidal particles; (iii) adsorption and bridging of Ep chain for the NPs and heavy metal ions. Results indicated that the destabilization of colloid was induced by the coexisting HA and higher removal was achieved as ions adsorption was enhance in the presence of HA complexation. On the basis of that, the extraction of polysaccharide is a promising candidate for its high coagulation performance in water treatment.  相似文献   
34.
Extant species of Muridae occupy a wide array of habitats and have diverse dietary habits. Consequently, their dental microwear patterns represent a potential clue to better understand the paleoecology of their extinct relatives, which are abundant in many Old World Neogene localities. In this study, dental microwear is investigated for specimens of 17 extant species of murine and deomyine rodents in order to test the reliability of this method and infer dietary preferences on the fossil species Saïdomys afarensis. This extinct form comes from a mid-Pliocene site (AL 327) located at the Hadar Formation (Ethiopia) known to have delivered many hominid specimens of Australopithecus afarensis. A significant correlation between microwear patterns and diet is detected. Thus, grass, fruit, and insect eaters display, respectively, high amounts of fine scratches, wide scratches, and large pits. Moreover, some aspects of the paleoecology of S. afarensis, including feeding habits, could be assessed in regard to its dental microwear pattern. Indeed, it probably had feeding habits similar to that of living grass eaters. These results concur with the presence of open to woodland areas covered by an herbaceous vegetal layer, including monocotyledons, in the vicinity of this mid-Pliocene locality.  相似文献   
35.
While the world is going into different tourism expectations, the tourism understanding in Turkey is defined as tourism in the sea-sand-sun triangle. However, it is possible to contribute to the income and local development of the indigenous people by developing nature-based tourism. Besides, with the sustainable use and preservation of the natural-cultural assets, the damage of the traditional tourism industry on the natural and cultural environment could be reduced. In this study, it is aimed to bring up the nature-based tourism concept in Çanakkale by evaluating the nature-based tourism industry in the general of Turkey and assessing the natural-cultural resources that Çanakkale comprehends. The most important areas that have a nature-based tourism potential in Çanakkale and the tourism activities that are most suitable for these areas have been determined.  相似文献   
36.
煤的低温氧化实验研究及红外光谱分析   总被引:7,自引:0,他引:7  
对不同温度下的氧化煤样通过红外光谱分析其微观结构及特征,得到煤样在不同低温氧化阶段的基团变化,从微观角度掌握煤样氧化过程的变化规律.通过对唐口煤矿1302工作面煤样的低温氧化和红外光谱分析,得到唐口煤矿煤样在低温氧化阶段的自燃倾向性和氧化过程中微观结构的变化规律,该成果为制定矿井内火灾的防治技术提供了科学依据.  相似文献   
37.
Material recovery processes are presented as the optimum option for recycling plastic wastes as a means of recovering hydrocarbon resources. There exist a large variety of automated material recovery processes for recycling of such wastes but each with significant limitations. Of these, the separation based on differences in densities is advocated as the optimum process either for producing recycled products or preparing wastes for subsequent recovery processing.Density separation processes based on cyclone type density media separation (DMS) is presented as an important, potential method for increasing plastics recycling process capacities. It is demonstrated to have the capacity to separate a significantly larger range of particle sizes than those presently processed industrially. The mathematical relationship for the prediction of quality of typical LARCODEMS type density media separations by particle size and density as expressed by the Ecart Probable is presented.A proposed device configuration is presented for density media separation to optimize the recovery and purity of both density fractions produced. It is also suggested that to be economically viable, a large scale of operation is required for industrial plastics recycling operations recovering and producing a number of different plastics with a purity to be used as a substitute for virgin material.  相似文献   
38.
目的 在装药结构的热安全性试验时选择合理的加热方法.方法 从燃料、加热速率、温度范围、温度可控性、温区可控性、对试件影响等方面对开放油池火烧、可控喷射火烧、红外辐射灯阵、电加热带、电加热箱等常用的加热方式进行对比分析.结果 对于快烤加载,红外辐射灯阵兼具开放油池火烧和可控喷射火烧的优势,能够实现温度为800~1200℃、升温速率不低于200℃/s、温度控制偏差不大于5%的模拟火烧温度稳定控制,且具备清洁环保的优势;对于慢烤加载,红外辐射灯阵兼具电加热带和电加热炉加载的优势,能够实现温升速率3.3℃/h~1.0℃/min可调节,加热温度不低于400℃,温度分区不低于4个的分区慢速烤燃温度控制,且不会给试样反应等级带来额外影响.结论 合理选择慢烤、快烤加热方式,避免对装药结构的反应等级产生影响,是装药结构的热安全性试验时需重视的一个问题.  相似文献   
39.
试图通过试验,研究从林火点火源的红外辐射谱特性确定火焰性质的方法。为此,研制了模拟试验台,可以同时测定各特征火焰区的红外辐射谱和平均温度。用普朗克定律和维恩位移定律对试验数据进行了处理。对三种典型的引火源(烟头、树枝和纸)进行研究的结果表明:引火源的辐射特征波长在1.1-2.1um,3.8-4.0um,7.8-8.2um波段内分布,此波长与各火焰区的特征温度存在对应关系。辐射温度随波长变化。在短波长处较低,此结果与将火焰辐射处理成黑体辐射时的普朗克定律大致相符  相似文献   
40.
Zusammenfassung  2-Chlorvinylarsindichlorid (Lewisit I) und 2,2′-Dichlordivinylarsinchlorid (Lewisit II) reagieren bei Raumtemperatur in einer Substitutionsreaktion schnell und quantitativ mit Dithiolen. Die Derivate wurden massenspetrometrisch identifiziert. Sie sind mit GC/ECD detektierbar. Diese Reaktionen k?nnen zur gaschromatographischen Bestimmung von Lewisiten in Wasser-und Bodenproben eingesetzt werden.   相似文献   
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