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81.
A three-stage study has been carried out with rainbow trout (Oncorhyncus mykiss) to develop analytical approaches which can provide a fingerprint for tainting by oil sands chemicals from process-affected waters and natural sources. The objective was to find a simpler alternative to sensory evaluation. In the first stage, a set of seven test compounds was added to fish tissue which was analysed by headspace and solvent (dichloromethane, DCM) extraction followed by gas chromatography-mass spectrometry (GC-MS). In the second stage, fingerlings (5-20 g) were exposed for 96 hours to the test compound mixture at 1.0 and 0.5 times the estimated tainting threshold concentrations. In the final stage, fingerlings were exposed for 96 hours to an oil sands process water at 5, 10, 20 and 50% concentrations in clean water. None of the test compounds was identified in DCM extracts of tissue from exposed fish. Two long-chain aldehydes, hexadecanal and 9-octadecenal, were tentatively identified in these extracts by matching of mass spectra with library spectra. 相似文献
82.
Yu. S. Gorbunov A. G. Ageev R. V. Vasil’eva B. M. Korol’kov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(3):166-170
A system for the direct measurement of steam flow in steam lines after a steam generator, which utilizes a special design
of pneumometric tubes and a computing unit that accounts for variation in steam pressure, has been developed to improve the
quality of water-level regulation in the steam generators of VVéR-1000 power-generating units in the stationary and transitional
modes. The advantage of the pneumometric tubes consists in their structural simplicity, high erosion resistance, and absence
of irrevocable losses during measurement of steam flow. A similar measurement system is used at foreign NPP. The measurement
system in question has been placed in experimental service at the No. 3 unit of the Balakovo NPP, and has demonstrated its
worthiness. This measurement system can also be used to determine steam flow in the steam lines of NPP units with VVéR-1000
and VVéR-440 reactors, and PBMK-1000 power-generating units.
__________
Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 23–26. 相似文献
83.
Strategy for olive mill wastewater treatment and reuse with a sewage plant in an arid region. 总被引:1,自引:0,他引:1
This study was conducted to evaluate the treatability of OMW (olive mill wastewater) with sewage and sewage sludge, which could supplement nutrients and microbes required for OMW treatment and reduce its possible toxicity. The amount of OMW added to an aeration tank was based on the loading difference between the designed and actual COD loads, while the amount added to anaerobic digestion for energy recovery was determined by CH4 production. The COD removal efficiencies were 70-85% for both systems. Compost of OMW with dried sewage sludge also showed a similar temperature profile without OMW addition. This strongly suggested that OMW can be treated at a sewage plant without pretreatment and the treated effluent can be reused in irrigation for an arid region. 相似文献
84.
The secondary effluent from municipal plants in Korea generally represents higher BOD with lower SS. Therefore, more soluble forms of organics and NH4-N need to be removed to improve its effluent for reuse. In this study reuse possibility of secondary effluent and CSO (combined sewer overflow) using BAF (biological aerated filter) was evaluated. The tertiary application with 1.2 h EBCT, SS, BOD and COD showed stable concentrations less than 1.3, 1.3 and 6.2 mg/L, respectively. Nitrogen could be nitrified even at 7 degrees suggesting BAF can be used for a water reuse method as well as an effective add-on facility in cold regions. However, BAF was not stable with CSO application at increased flow rates suggesting CSO must be equalised prior to application. Disinfection was necessary even during normal weather conditions. 相似文献
85.
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87.
Strategic partnerships are commonplace in today's global economy. Effective use of partnerships are viewed increasingly as an important issue facing small, growth-oriented firms. A key debate is how small firms should manage supplier partnerships. Contrasting the debate about the extent to which small firms are inertial versus adaptive, the impact of growth on value chain partnerships with suppliers was investigated. Data collected from 91 pharmaceutical-related firms is used to test the proposition that firm growth is related positively to maintaining or to expanding relationships with suppliers, not to terminating partnerships. The paper further posits that this relationship between firm growth and the amount purchased from a supplier is moderated by the perceived effectiveness of the value-chain partnerships such that when effectiveness is higher, the relationship between sales growth and the amount purchased from a value-chain partner is stronger. The propositions, which are tested with regression analysis, are supported partially. 相似文献
88.
We apply a discrete choice approach to model the empirical behaviour of the Federal Reserve in changing the federal funds target rate, the benchmark of short‐term market interest rates in the US. Our methods allow the explanatory variables to be nonstationary as well as stationary. This feature is particularly useful in the present application as many economic fundamentals that are monitored by the Fed and are believed to affect decisions to adjust interest rate targets display some nonstationarity over time. The chosen model successfully predicts the majority of the target rate changes during the time period considered (1994–2001) and helps to explain strings of similar intervention decisions by the Fed. Based on the model‐implied optimal interest rate, our findings suggest that there is a lag in the Fed's reaction to economic shocks during this period. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
89.
Markets reacted strongly to the World Trade Center attacks both in Europe and in the United States. The extent of this crisis was difficult to assess at the time, underlining the need for a specific tool to measure the magnitude of financial crises. A first measure was recently proposed and applied to the foreign exchange market by Zumbach et al. (2000a,b ). Their measure relies on an analogy with geophysics; the related index of market shocks (IMS) that we propose here is also the counterpart of the Richter scale used for earthquakes. We apply this measure on the French and the American stock markets to put large market events into perspective. The crisis triggered by the September attacks was actually the worst since 1987, and the ninth worst when compared to major historical ones. 相似文献
90.
This paper suggests that the capacity of indigenous groups to engage effectively in a range of planning activities is crucial to achieving land justice and community goals. This argument is relevant in the face of long-standing tensions between indigenous peoples residing in post-settler societies and nation-states such as Australia, Canada, and New Zealand over questions of land and natural resource use. The paper argues that effective planning is crucial for (i) protecting indigenous interests by engaging the planning activities of the state, (ii) the successful acquisition of lands through legal land claim processes, and (iii) helping indigenous communities achieve their goals by implementing effective community-based planning processes. 相似文献