国际镍公司 Acton 贵金属精炼厂的溶剂萃取

由于安大略省 Sudbury 地区的 Cu-Ni 硫化矿中含有微量贵金属,因而使得国际镍公司包括了贵金属的精炼。最初发现该矿,大约在一百年前,即1883年。六年后,在此矿床中发现了重要的铂族金属矿物—砷铂矿(PtAs_2)。通常供国际镍公司精炼厂用的矿石,其含量为1ppm 左右的铂族金属,还有引人注意的大量的 Au 和 Ag。     

Pressure waves in the aorta during isolated abdominal belt loading: the magnitude, phasing, and attenuation

While rupture of the aorta is a leading cause of sudden death following motor vehicle crashes, the specific mechanism that causes this injury is not currently well understood. Aortic ruptures occurring in the field are likely due to a complex combination of contributing factors such as acceleration, compression of the chest, and increased pressure within the aorta. The objective of the current study was to investigate one of these factors in more detail than has been done previously; specifically, to investigate the in situ intra-aortic pressure generated during isolated belt loading to the abdomen. Ten juvenile swine were subjected to dynamic belt loads applied to the abdomen. Intraaortic pressure was measured at multiple locations to assess the magnitude and propagation of the resulting blood pressure wave. The greatest average peak pressure (113.6 +/- 43.5 kPa) was measured in the abdominal aorta. Pressures measured in the thoracic aorta and aortic arch were 70 per cent and 50 per cent, respectively, that measured in the abdominal aorta. No macroscopic aortic trauma was observed. To the authors' knowledge the present study is the first one to document the presence, propagation, and attenuation of a transient pressure wave in the aorta generated by abdominal belt loading. The superiorly moving wave is sufficient to generate hydrostatic and intimal shear stress in the aorta, possibly contributing to the hypothesized mechanisms of traumatic aortic rupture.     

西班牙灌溉现代化对水质和水量的影响研究

以西班牙埃布罗（Ebro）河流域为例,分析了灌溉现代化过程对水量和水质的影响,旨在对优化农业用水进行深入分析和讨论,研究过程使用了基于水量核算的概念性方法。结果表明,如果灌区的位置和灌溉回流水质允许再次使用回流水,则灌溉现代化仍涉及耗水量增加的问题。另外,灌溉现代化减少了灌溉回流的水量和污染物的含量,提高了接收水体的水质。水管理现代化是使新的灌溉基础设施所产生的经济、社会和环境效益最大化的需要。     

首台新型水轮发电机组在挪威海格塞特大坝进行中间试验

清洁能源公司（Clean Power）已在挪威海格塞特（Hegset）大坝安装其首台Turbinator机组,这是一种新型的水轮发电机组。Turbinator机组是将一台轴流式水轮机和一台发电机紧凑而又密封地组合在一起,利用环境排水口的泄水发电。对这种新型水轮发电机组的研发过程及优良性能等作了简单介绍,并对其开发利用前景进行了展望。     

美国可持续水规划采用的水资源管理技术

围绕水资源的可持续发展,结合美国缺水方面的管理经验,介绍了目前美国可持续水规划中所使用的一些水资源管理技术,包括缺水管理和流域生态管理方面的技术,如实施最佳流域管理实践（BMP）,以及低影响开发（LID）等。并对项目选择和优先排序的标准,以及美国正在实施的＂大沼泽地＂生态系统恢复项目进行了简要介绍。     

Global optimization method for combined spherical-cylindrical wrapping in musculoskeletal upper limb modelling

In musculoskeletal modelling, many muscles cannot be represented as straight lines from origin to insertion because the bony and musculotendinous morphology of neighboring structures causes them to wrap. The majority of these passive structures can be adequately described as simple geometric shapes such as spheres and cylinders. Techniques for describing smooth muscle paths around multiple obstacles have been developed for modelling use. Until now obstacle-set methods have combined the path of single structures. This does not analytically define the shortest smooth path around multiple objects. When a sphere is included in a multiple-object wrapping algorithm, muscle paths around that sphere are restricted to a bundle of planes containing the sphere center. This assumed restriction can compromise the iterative process for finding the true shortest muscle path that satisfies all restrictions of a smooth path. This can cause model instability. The new method involves the determination of the shortest smooth muscle path in a spherical and cylindrical wrapping algorithm. A typical example is musculoskeletal modelling of the upper limb, where the muscle fibers have to wrap over this combination of obstacles.     

Tribological assessment of a flexible carbon-fibre-reinforced poly(ether-ether-ketone) acetabular cup articulating against an alumina femoral head

New material combinations have been introduced as the bearing surfaces of hip prostheses in an attempt to prolong their life by overcoming the problems of failure due to wear-particle-induced osteolysis. This will hopefully reduce the need for revision surgery. The study detailed here used a hip simulator to assess the volumetric wear rates of large-diameter carbon-fibre-reinforced pitch-based poly(ether-ether-ketone) (CFR-PEEK) acetabular cups articulating against alumina femoral heads. The joints were tested for 25 x 10(6) cycles. Friction tests were also performed on these joints to determine the lubrication regime under which they operate. The average volumetric wear rate of the CFR-PEEK acetabular component of 54 mm diameter was 1.16 mm(3)/10(6) cycles, compared with 38.6 mm(3)/10(6) cycles for an ultra-high-molecular-weight polyethylene acetabular component of 28 mm diameter worn against a ceramic head. This extremely low wear rate was sustained over 25 x 10(6) cycles (the equivalent of up to approximately 25 years in vivo). The frictional studies showed that the joints worked under the mixed-boundary lubrication regime. The low wear produced by these joints showed that this novel joint couple offers low wear rates and therefore may be an alternative material choice for the reduction of osteolysis.     

Effectiveness of participatory ergonomic interventions on health outcomes: a systematic review

The objective of this study was to conduct a systematic review of the literature on the effectiveness of participatory ergonomic (PE) interventions for improving workers' health. The search strategy targeted six electronic databases and identified 442 potential articles. Each article was examined by pairs of reviewers for relevance (assessed a participative ergonomic workplace intervention, with at least one health outcome, published in English in peer reviewed literature). Twenty-three articles met relevance criteria and were then appraised for methodological strength. Using a best evidence synthesis approach, 12 studies that were rated as 'medium' or higher provided partial to moderate evidence that PE interventions have a positive impact on: musculoskeletal symptoms, reducing injuries and workers' compensation claims, and a reduction in lost days from work or sickness absence. However, the magnitude of the effect requires more precise definition.