The Formation Evaluation Tool （FET） introduced in the paper represents a new generation of formation evaluation systems developed and manufactured by China Oilfield Services Limited （COSL）, CNOOC, using a FET tech...The Formation Evaluation Tool （FET） introduced in the paper represents a new generation of formation evaluation systems developed and manufactured by China Oilfield Services Limited （COSL）, CNOOC, using a FET technology transfer from Crocker Research, Australia. The system has been applied successfully in the Bohai Sea and South China Sea. For instance, a multilayered oil and water system has been confirmed with the aid of accurate formation pressure tests, even in very thin beds and edge water reservoirs, overcoming the difficulty of determining this kind of oil-water and gas-water contacts. Moreover, the FET pumping and real-time fluid monitoring function allows acquiring a true sample of formation fluid unpolluted by drilling mud which plays an important role in determining the fluid properties of the target stratum and analyzing the fluid component. The principles and purpose of the Formation Evaluation Tool （FET） will be briefly introduced and successful examples of the application of the technology will be described in detail in this paper.展开更多
The present study focused on the evaluation of the contamination by three heavy metals （Cd, Cu and Zn） of a bony fish, Mullus surmuletus L., 1758, caught in the Bay of Oran. This reflects the quality of fish habitat...The present study focused on the evaluation of the contamination by three heavy metals （Cd, Cu and Zn） of a bony fish, Mullus surmuletus L., 1758, caught in the Bay of Oran. This reflects the quality of fish habitat as species common Algerian coastal waters and enjoyed by a large fish-eating population. Monthly sampling was spread over a period of six months （December 2011-May 2012）. Given their physiological importance in the body, muscle, liver and gonads were targeted. Metal concentrations were determined by atomic absorption spectrophotometry in flame depends on three parameters （sex, size and month）. It appears from this study that the target organs of rouget （M. surmuletus） accumulate three metal pollutants sought. The highest values are those of zinc, copper and cadmium are at concentrations at least important. The results, statistically treated, showed no significant difference between the concentrations of trace metals both sexes and at all three organs considered. The average dose of heavy metals found in the mullet compared to those provided by the literature relating to DMA （Maximum Allowable Doses）, are not worrisome. Concentration levels of toxic metals reflect a certain metal pollution in the Bay of Oran.展开更多
The leaching behaviour of Cu and Zn from contaminated soils at a copper mine was investigated using four extractants： citric acid （CA）, oxalic acid （OA）, ethylenediaminetetraacetic acid （EDTA） and nitrilotriace...The leaching behaviour of Cu and Zn from contaminated soils at a copper mine was investigated using four extractants： citric acid （CA）, oxalic acid （OA）, ethylenediaminetetraacetic acid （EDTA） and nitrilotriacetic acid （NTA）. Six soil samples were characterized for the distribution of four chemical fractions of Cu or Zn （acid-soluble, reducible, oxidizable and residual）. For the extraction of Cu, EDTA is more effective than other extmctants when the concentration is less than 0.02 mol/L. The leaching efficiency for Cu was at least 15% higher for EDTA than for the other extractants at the same concentrations. Similar leaching behaviour was observed in the extraction of Zn. After extraction by CA, OA, EDTA or NTA, the acid-soluble fractions and the reducible fractions of Cu were the main fractions extracted. The potential environmental risks related to speciation were evaluated, and after extraction these risks were reduced.展开更多
Road surface condition evaluation involves the collection of data over pavement surface for different types of distresses. The exercise consumes a lot of resources if the whole road section length is surveyed and may ...Road surface condition evaluation involves the collection of data over pavement surface for different types of distresses. The exercise consumes a lot of resources if the whole road section length is surveyed and may be prone to errors as a result of surveyors＇ fatigue. It is therefore important to develop a representative sample to be used when evaluating road condition manually. This study aimed at determining an adequate sample size for section level as well as a way forward for network level condition evaluation of highways in Nepal. Again the study was conducted to quantify the effects of altering the sample unit size for performing a distress survey according to the PCI （pavement condition index） and SDI （surface distress index） method separately for asphalt surfaced roads. The effect of reducing/increasing sample unit size was investigated adopting visual examination through field survey by eight teams in July, 2015, along the section of Banepa-Bardibas highway. The PCI was then calculated for each sample unit using standard deduct curves and PCI calculation methodology as per SHRP （Strategic Highway Research Program） recommendations and the computation of SDI was done as per DoR （Department of Roads） guidelines. The results show that 13% sample unit are needed for SDI and 21% for PCI computation, however, the results are out of the significant level. This is higher than DoR and SHRP guidelines. Again no strong relationship is observed between SDI and PCI values.展开更多
文摘The Formation Evaluation Tool （FET） introduced in the paper represents a new generation of formation evaluation systems developed and manufactured by China Oilfield Services Limited （COSL）, CNOOC, using a FET technology transfer from Crocker Research, Australia. The system has been applied successfully in the Bohai Sea and South China Sea. For instance, a multilayered oil and water system has been confirmed with the aid of accurate formation pressure tests, even in very thin beds and edge water reservoirs, overcoming the difficulty of determining this kind of oil-water and gas-water contacts. Moreover, the FET pumping and real-time fluid monitoring function allows acquiring a true sample of formation fluid unpolluted by drilling mud which plays an important role in determining the fluid properties of the target stratum and analyzing the fluid component. The principles and purpose of the Formation Evaluation Tool （FET） will be briefly introduced and successful examples of the application of the technology will be described in detail in this paper.
文摘The present study focused on the evaluation of the contamination by three heavy metals （Cd, Cu and Zn） of a bony fish, Mullus surmuletus L., 1758, caught in the Bay of Oran. This reflects the quality of fish habitat as species common Algerian coastal waters and enjoyed by a large fish-eating population. Monthly sampling was spread over a period of six months （December 2011-May 2012）. Given their physiological importance in the body, muscle, liver and gonads were targeted. Metal concentrations were determined by atomic absorption spectrophotometry in flame depends on three parameters （sex, size and month）. It appears from this study that the target organs of rouget （M. surmuletus） accumulate three metal pollutants sought. The highest values are those of zinc, copper and cadmium are at concentrations at least important. The results, statistically treated, showed no significant difference between the concentrations of trace metals both sexes and at all three organs considered. The average dose of heavy metals found in the mullet compared to those provided by the literature relating to DMA （Maximum Allowable Doses）, are not worrisome. Concentration levels of toxic metals reflect a certain metal pollution in the Bay of Oran.
基金Project(2232013A3-08)supported by the Fundamental Research Funds for the Central Universities,ChinaProject supported by Shanghai Pujiang Program and DHU Distinguished Young Professor Program,China
文摘The leaching behaviour of Cu and Zn from contaminated soils at a copper mine was investigated using four extractants： citric acid （CA）, oxalic acid （OA）, ethylenediaminetetraacetic acid （EDTA） and nitrilotriacetic acid （NTA）. Six soil samples were characterized for the distribution of four chemical fractions of Cu or Zn （acid-soluble, reducible, oxidizable and residual）. For the extraction of Cu, EDTA is more effective than other extmctants when the concentration is less than 0.02 mol/L. The leaching efficiency for Cu was at least 15% higher for EDTA than for the other extractants at the same concentrations. Similar leaching behaviour was observed in the extraction of Zn. After extraction by CA, OA, EDTA or NTA, the acid-soluble fractions and the reducible fractions of Cu were the main fractions extracted. The potential environmental risks related to speciation were evaluated, and after extraction these risks were reduced.
文摘Road surface condition evaluation involves the collection of data over pavement surface for different types of distresses. The exercise consumes a lot of resources if the whole road section length is surveyed and may be prone to errors as a result of surveyors＇ fatigue. It is therefore important to develop a representative sample to be used when evaluating road condition manually. This study aimed at determining an adequate sample size for section level as well as a way forward for network level condition evaluation of highways in Nepal. Again the study was conducted to quantify the effects of altering the sample unit size for performing a distress survey according to the PCI （pavement condition index） and SDI （surface distress index） method separately for asphalt surfaced roads. The effect of reducing/increasing sample unit size was investigated adopting visual examination through field survey by eight teams in July, 2015, along the section of Banepa-Bardibas highway. The PCI was then calculated for each sample unit using standard deduct curves and PCI calculation methodology as per SHRP （Strategic Highway Research Program） recommendations and the computation of SDI was done as per DoR （Department of Roads） guidelines. The results show that 13% sample unit are needed for SDI and 21% for PCI computation, however, the results are out of the significant level. This is higher than DoR and SHRP guidelines. Again no strong relationship is observed between SDI and PCI values.
