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Both body mass and surface area are factors determining the essence of any living organism. This should also hold true for an extinct organism such as a dinosaur. The present report discusses the use of a new 3D laser scanner method to establish body masses and surface areas of an Asian elephant (Zoological Museum of Copenhagen, Denmark) and of Plateosaurus engelhardti, a prosauropod from the Upper Triassic, exhibited at the Paleontological Museum in Tübingen (Germany). This method was used to study the effect that slight changes in body shape had on body mass for P. engelhardti. It was established that body volumes varied between 0.79 m3 (slim version) and 1.14 m3 (robust version), resulting in a presumable body mass of 630 and 912 kg, respectively. The total body surface areas ranged between 8.8 and 10.2 m2, of which, in both reconstructions of P. engelhardti, ∼33% account for the thorax area alone. The main difference between the two models is in the tail and hind limb reconstruction. The tail of the slim version has a surface area of 1.98 m2, whereas that of the robust version has a surface area of 2.73 m2. The body volumes calculated for the slim version were as follows: head 0.006 m3, neck 0.016 m3, fore limbs 0.020 m3, hind limbs 0.08 m3, thoracic cavity 0.533 m3, and tail 0.136 m3. For the robust model, the following volumes were established: 0.01 m3 head, neck 0.026 m3, fore limbs 0.025 m3, hind limbs 0.18 m3, thoracic cavity 0.616 m3, and finally, tail 0.28 m3. Based on these body volumes, scaling equations were used to assess the size that the organs of this extinct dinosaur have.  相似文献   
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Community‐based water supply (CBWS) is an example of how a community manages common pool resources (CPR). This results in an alternative approach to solve water supply problems in developing countries by enhancing community participation in managing water supply. This research evaluates the sustainability of five CBWS projects in Cikarang, Indonesia by using Ostrom's design principles, with additional sustainability factors found in the Sustainable Development Goal (SDG) on drinking water and groundwater sustainability. Quinn et al. (2007) criteria were used in the analysis, and the results show that the management of four CBWS institutions were absent and one CBWS institution was weak. With regards to the SDG's drinking water target, the CBWS institutions were unable to comply with safe water standards, and in terms of groundwater sustainability, efforts to monitor and sustain groundwater tables were absent. Results from this research suggest that more focus must be placed on water quality and groundwater sustainability for CBWS projects.  相似文献   
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铁钙复合絮凝剂HC211用于钻井废水处理性能研究   总被引:2,自引:0,他引:2  
探讨了在不同PH值、温度、剂量及酸化预处理条件下,铁钙复合絮凝剂HC211絮凝特性和絮凝效果的好坏。研究表明铁钙复合絮凝剂HC211在PH值为8-10,温度为15℃,剂量在4‰左右有好的絮凝效果。尤其在酸化预处理后,铁钙复合絮凝剂HC211絮凝效果更佳。  相似文献   
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