雷蒙磨粉机在铜镍铂（族）矿石标准物质制备中的应用

介绍了雷蒙磨粉机原理。采用雷蒙磨粉机，对不同含量铜镍铂（族）矿石标准样品加工至粒度小于0．074mm。选择合适的磨球和样品质量比，球磨机磨-混24～72h。样品经粒度筛分试验、均匀度及稳定性检验，证明其中被检验元素分布均匀。     

地勘单位企业化改革的理性思考——东北煤田地质局一0七队产权制度改革的启示

东北煤田地质局107队通过资本运作，职工参股，资本量化，产权多元，股本流动等多种形式，试行模拟改制，调动了投资者、经营者、劳动者三方面的积极性，为推动地勘单位的企业化改革进程积累了一定的经验。     

Estimating Radon Flux and Environmental Radiation Dose from Decommissioning Uranium Mill Tailings and Mining Debrisg

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Socio-economic aspects of boat-based ecotourism during the sardine run within the Pondoland Marine Protected Area,South Africa

Understanding recreational aspects of the tourism industry developing around the KwaZulu-Natal sardine run is important for the protection and sustainability of the Pondoland Marine Protected Area (MPA), on the south-east coast of South Africa. Between June and July 2007, a total of 128 people visited this area to experience the sardine run using boat-based access. An onsite questionnaire survey of 108 (84.4%) participants at Port St Johns and Mbotyi indicated that the direct value of their visit was around R5.47 million (95% CI = R5.14–5.82 million). Although the benefits of the sardine run tourism industry extend throughout the South African economy, local indigenous communities receive little direct benefit. Almost half of all sardine run participants, however, showed a willingness to contribute R500 or more towards a community development programme. On a ranking from one (poor) to five (excellent), the average participant's response to overall quality of the experience and quality of the dive charter was 3.9 and 4.4, respectively. Over a quarter (27%) of participants never saw a sardine during their visit, despite the fact that their trip was marketed as ‘the sardine run’, so participant experiences often did not meet with expectations. The sardine run within the Pondoland MPA is currently an undermarketed and underexploited resource.     

Ecosystem considerations of the KwaZulu-Natal sardine run

The annual winter sardine run along the South African east coast impacts the KwaZulu-Natal (KZN) coastal system in a variety of ways. These include ecological impacts, such as enrichment of a largely oligotrophic environment, competition between migrant sardine Sardinops sagax, other migrant and resident small pelagic fish species, and interactions with predators, as well as the socio-economic impacts of the sardine run on the local people. Enrichment of KZN coastal waters with organic nitrogen contained within the sardine is compared with alternative sources of nitrogen such as upwelling, river, sewage and stormwater runoff, and groundwater discharge. The sardine run appears to contribute most nitrogen to this system—96 000 t compared to 500–3 300 t for each of the other significant sources at trophic level 2, although upwelling estimates are extremely wide. Nonetheless, the majority of surviving sardine, their young and predators return southwards, suggesting that the nett export of nitrogen to KZN waters during the run is likely to be of a similar order of magnitude as that from other sources. Further, whereas the sardine supply of nitrogen is exclusively during winter, the bulk of the riverine input is in summer, thus ensuring that nitrogen supply in the region is maintained at fairly constant levels throughout the year. Competition for food between small pelagic fish is minimised by resource partitioning, but further dietary data are needed for resident species. Although interactions between sardine and top predators must exist, further studies are needed to confirm links between top predator life cycles and the sardine run. The estimated value of sardine as a tourist spectacle is compared to that from a seasonal beach-seine or boat-based purse-seine fishery for this species. Whereas the estimated value of the sardine as a tourist attraction appears substantially higher than could be derived from catching them, the small-scale beach-seine fishery itself draws tourists and also provides limited, seasonal employment opportunities.     

Partitioning of metals (Fe,Pb, Cu,Zn) in urban run‐off from the Kaikorai Valley,Dunedin, New Zealand

Urban run‐off from a catchment in Dunedin, New Zealand was sampled and chemically characterised (iron (Fe), lead (Pb), copper (Cu), zinc (Zn) in total and <0.4 (im fractions, suspended solids, nitrogen (N), phosphorus (P), dissolved organic carbon, major ions, pH) during base flows, and storm flows from five rainfall events. Fe and Pb were found to be predominantly particle‐associated (>0.4 μm) and their concentrations increased significantly at the beginning of storm run‐off. In contrast, the majority of Cu and Zn was found in the <0.4μm fraction before rainfall events but during the initial period of storm flows a significant proportion of Cu and Zn was also present in the >0.4 μm fraction. The results indicate that Cu and Zn may be more bio‐available, and more difficult to remove by storm‐water treatment, than Pb. The pH level and the concentration of major ions (Ca⁺², Na⁺, Mg⁺², K⁺), dissolved reactive phosphorus, and nitrate generally decreased during storm flows as a result of dilution by rainwater. Concentrations of total N and P often increased during the initial period of storm run‐off, which was likely because of wash‐off of particulate plant material.     

斜坡堤波浪爬高和越浪数值模拟

基于FLUENT软件,采用k-ε湍流模型和VOF方法追踪自由表面,由连续性方程和动量方程推导出源函数,根据数值水槽各个区段的功能设置,借助其UDF二次开发功能,实现无反射的源造波,在验证水槽两端消波有效性的基础上,数值模拟规则波在不可渗透斜坡堤上的波浪爬高和越浪。通过与物模试验研究成果相对比,表明建立的数值水槽具有高效性和较高精度,可供实际工程参考应用。     

Microstructure characterization of mechanically activated hematite using XRD line broadening

The effect of dry milling in a vibratory mill on the structural changes and microstructural characteristics of hematite using different methods was investigated. We have described the line profile analysis (LPA) to extract the size of coherently diffracting domains and the lattice strain of activated hematite in a vibratory mill. The Warren–Averbach and Williamson–Hall methods were used as the main tools for characterization. The changes in the particle size, surface area and new phase formation of hematite concentrate were also investigated. It was concluded that the breakage and agglomeration of particles take place mainly at lower and higher levels of specific energy input, respectively. The pores in agglomerates remain accessible for the nitrogen gas. Milling of hematite increased specific surface area up to 18.4 m²/g. The hematite milled under various levels of specific energy input did not undergo a significant reaction or phase transformation during milling. The Williamson–Hall method confirms its merit for a rapid overview of the line broadening effects and possible understanding of the main causes. The anisotropic character of line broadening for deformed hematite as a function of specific energy input was revealed. Higher level of specific energy input favors the generation of small crystallite size, higher microstrain, BET surface area, amorphization and line breadth. The Warren–Averbach method suggested that the nanocrystalline hematite with grain sizes of 73.5–12.2 nm was formed by mechanical treatment using different milling intensities in the vibratory mill. The root mean square strain (RMSS) at L = 10 nm varies between 1.7 × 10^− 3 and 4.0 × 10^− 3 depending on the level of energy input. Limits in the applicability of Williamson–Hall method and reliability of the results are discussed in detail.     

Propagation of drought through groundwater—a new approach using linear reservoir theory

The effect of drought on groundwater heads and discharge is often complex and poorly understood. Therefore the propagation of a drought from groundwater recharge to discharge and the influence of aquifer characteristics on the propagation was analysed by tracking a drought in recharge through a linear reservoir. The recharge was defined as a sinusoid function with a period of 1 year. The decrease in recharge owing to drought was simulated by multiplying the recharge during 1 year with a drought fraction between 0 and 1, which represents a decrease in the recharge of 100 to 0%, respectively. The droughts were identified using the threshold level approach, with a threshold that is constant in time. For this case analytical formulations were derived, which express the drought duration and deficit in the groundwater discharge in terms of the decrease in recharge, the reservoir coefficient that characterizes aquifer properties and the height of the threshold level. The results showed that the delay in the groundwater system caused a shift of the main part of the decrease in recharge from the high‐flow to the low‐flow period. This resulted in an increase in drought deficit for discharge compared with the drought deficit for recharge. Also the development of multiyear droughts caused an increase in drought deficit. The attenuation in the groundwater system caused a decrease in drought deficit. In most cases the net effect of these processes was an increase of drought deficit as a result of the propagation through groundwater. Only for small droughts the deficit decreased from recharge to discharge. The amount of increase or decrease depends on the reservoir coefficient and the severity of the drought. Under most conditions a maximum in the drought deficit occurred for a reservoir coefficient of around 200 days. Copyright © 2003 John Wiley & Sons, Ltd.     

Socio-economic implications of the KwaZulu-Natal sardine run for local indigenous communities

The economic and social effects of the annual sardine run on the indigenous community on the south coast of KwaZulu-Natal, South Africa, were assessed using data gathered from questionnaires and personal interviews with 329 members of the community. Their knowledge, perceptions and attitudes about the sardine run, as well as their level of involvement in, and the financial benefits accrued from it, were also assessed. Although around two-thirds of those interviewed were aware of the sardine run and just over half participated in it, only some 17% benefited financially from it. However, despite this low level of participation, the financial benefit to the community could amount to R17–18 million, and as much as R34–54 million if a multiplier effect of 2–3 is applied. There was a high level (over 70%) of willingness to learn more about the event, and to become more involved in training exercises that would allow local people to take advantage of opportunities arising from the sardine run. It is recommended that management strategies and development plans should be implemented towards assisting the indigenous communities to become more involved in the sardine run.