Diagenetic fluid types of the Cretaceous Bashijiqike formation are restored based on the analysis of petrographic,electron microprobe composition,inclusions homogenization temperature,salinity and vapor composition an...Diagenetic fluid types of the Cretaceous Bashijiqike formation are restored based on the analysis of petrographic,electron microprobe composition,inclusions homogenization temperature,salinity and vapor composition and laser carbon and oxygen isotope of diagenetic mineral,and regional geological background.Diagenetic fluid evolution sequence is analyzed on this basis.The crystalline dolomite cement has a low concerntration of Sr,high concerntration of Mn and higher carbon isotope,showing that the crystalline dolomite is affected by meteoric fresh water,associated with the tectonic uplift of late Cretaceous.Similarδ13CPDB,negative transfer ofδ18OPDB and the differentiation of the concerntration of Fe and Mn indicate that the diagenetic fluid of the vein dolomite cement is homologous with the diagenetic fluid of the crystalline dolomite cement,temperature and depth are the dominant factors of differential precipitation between these two carbonate cements.Anhydrite cements have high concerntration of Na,extremely low concerntration of Fe and Mn contents.Based on these data,anhydrite cements can be thought to be related to the alkaline fluid overlying gypsum-salt layer produced by dehydration.The barite vein has abnormally high concerntration of Sr,ultra-high homogenization temperature and high-density gas hydrocarbon inclusions,which is speculated to be the forward fluid by intrusion of late natural gas.Coexistence of methane inclusions with CO2 gas proves existence of acid water during the accumulation of natural gas in the late stages.Therefore,the alkaline environment and associated diagenesis between the meteoric fresh water in epidiagentic stage and carbonic acid in the late diagenesis have dominated the process of diagenesis and reservoir,the secondary porosity and fracture zone formed by gas accumulation is a favorable play for the exploration of ultra-deep reservoirs.展开更多
Reverse osmosis （RO） is proved to be the most reliable, cost effective, and energy efficient in producing fresh water compared to other desalination technologies. It is the fastest-growing desalination technology wi...Reverse osmosis （RO） is proved to be the most reliable, cost effective, and energy efficient in producing fresh water compared to other desalination technologies. It is the fastest-growing desalination technology with a greater number of installations around the world. The economic and technical performance of a medium-capacity RO desalination plant （2,000 m^3/day） proposed to be installed in Umm Qasr city south of Basra, Iraq is analyzed using DEEP-3.2 software created by the International Atomic Energy Agency （IAEA）. This port city is located on the Gulf shore and does not have any fresh water resources. The analysis shows that the cost of fresh water produced by this plant is US$0.986/m^3 with a good quality of fresh water （279 ppm）, which is a reasonable price for this remote area. The analysis also shows an increase in water production cost of about 12% at increased electricity price from 0.06 to 0.1 US$/kWh, 53% when the seawater salinity increased from 35,000 to 45,000 ppm, 2.5% when the seawater temperature decreased from 33 ℃ to 20 ℃, and 0.71% when the interest rate increased from 0% to 5%. Pumping fresh water from the Basra purification plant （located 175 km north of Umm Qasr） is 22.16 times the cost and 236.7% poorer quality than the fresh water produced by the RO plant.展开更多
[ Objective] The aim was to find optimum reaction conditions for synthetic process of Vitamin C. [ Method] Vitamin C sodium was used as raw material to prepare vitamin C through acidification, separation, desalination...[ Objective] The aim was to find optimum reaction conditions for synthetic process of Vitamin C. [ Method] Vitamin C sodium was used as raw material to prepare vitamin C through acidification, separation, desalination, recovery and purification. The impact of reaction time, tempera-ture, feedstock molar ratio and water content on the yield of vitamin C were investigated in the experiment. [Result] The optimum reaction condi- tions for synthetic process of Vitamin C were as follows： in the acidification test, reaction time 120 min, temperature 20 -30 ℃, the molar ratio be-tween hydrochloric acid and Vitamin C sodium 1 ： 1 and water content 41.0%. Under the above condition, the purity and yield of vitamin C reach 99.80% and 94.74% respectively. [Conclusion] The process can decrease consumption, enhance quality and recover of the product, improve the environmental pollution, shorten processing periods and reduce production cost. Thus, the process is suitable for industrialization. Key words Vitamin C; Vitamin C sodium; Acidification; China展开更多
This study aimed to characterize constituents of phosphorus （P） fractionation as wel as reciprocities among factors in sediments of a freshwater shal ow lake. [Method] Surface sediment was discretely sampled at 24 s...This study aimed to characterize constituents of phosphorus （P） fractionation as wel as reciprocities among factors in sediments of a freshwater shal ow lake. [Method] Surface sediment was discretely sampled at 24 sites through Van Veen grabs. Based on a modified sequential extraction scheme, P fractionation was determined as Fe/Al bound P （Fe/Al-P）, Ca bound P （Ca-P）, solute and re-ductive P （S/R-P） and organic P （OP）. Curve estimation and Pearson product-mo-ment correlation were employed for statistical analysis. [Result] Total P （TP） content ranged from 443 to 774 mg/kg. Inorganic P （IP） was the major component of TP, of which Ca-P was dominated with an average of 51%±9.7%. Average contents of P fractionation were in the fol owing order： Ca-P（51%） 〉 OP（29%） 〉 S/R-P（8%） 〉Fe/Al-P（7%）. The molar ratio of Fe to P was 11 - 20, close to the threshold value of P leaching. [Conclusion] In freshwater shal ow lakes, IP and Ca-P were prone to be relatively high, whereas Fe/Al-P was low compared with deep lakes. Occurrence of spatial y monotonic gradient indicated the primary causation of anthropogenic sources. Imminent sediment P liberation was also expected. Close associations a-mong TP, Fe/Al-P and Ca-P, implying that anthropogenic P was mainly bound to metals in particulates. Significant correlations of TOC and P fractionation highlighted endogenous mechanism and authigenic origin in sediments.展开更多
基金Projects(51674211,51534006)supported by the National Natural Science Foundation of China
文摘Diagenetic fluid types of the Cretaceous Bashijiqike formation are restored based on the analysis of petrographic,electron microprobe composition,inclusions homogenization temperature,salinity and vapor composition and laser carbon and oxygen isotope of diagenetic mineral,and regional geological background.Diagenetic fluid evolution sequence is analyzed on this basis.The crystalline dolomite cement has a low concerntration of Sr,high concerntration of Mn and higher carbon isotope,showing that the crystalline dolomite is affected by meteoric fresh water,associated with the tectonic uplift of late Cretaceous.Similarδ13CPDB,negative transfer ofδ18OPDB and the differentiation of the concerntration of Fe and Mn indicate that the diagenetic fluid of the vein dolomite cement is homologous with the diagenetic fluid of the crystalline dolomite cement,temperature and depth are the dominant factors of differential precipitation between these two carbonate cements.Anhydrite cements have high concerntration of Na,extremely low concerntration of Fe and Mn contents.Based on these data,anhydrite cements can be thought to be related to the alkaline fluid overlying gypsum-salt layer produced by dehydration.The barite vein has abnormally high concerntration of Sr,ultra-high homogenization temperature and high-density gas hydrocarbon inclusions,which is speculated to be the forward fluid by intrusion of late natural gas.Coexistence of methane inclusions with CO2 gas proves existence of acid water during the accumulation of natural gas in the late stages.Therefore,the alkaline environment and associated diagenesis between the meteoric fresh water in epidiagentic stage and carbonic acid in the late diagenesis have dominated the process of diagenesis and reservoir,the secondary porosity and fracture zone formed by gas accumulation is a favorable play for the exploration of ultra-deep reservoirs.
文摘Reverse osmosis （RO） is proved to be the most reliable, cost effective, and energy efficient in producing fresh water compared to other desalination technologies. It is the fastest-growing desalination technology with a greater number of installations around the world. The economic and technical performance of a medium-capacity RO desalination plant （2,000 m^3/day） proposed to be installed in Umm Qasr city south of Basra, Iraq is analyzed using DEEP-3.2 software created by the International Atomic Energy Agency （IAEA）. This port city is located on the Gulf shore and does not have any fresh water resources. The analysis shows that the cost of fresh water produced by this plant is US$0.986/m^3 with a good quality of fresh water （279 ppm）, which is a reasonable price for this remote area. The analysis also shows an increase in water production cost of about 12% at increased electricity price from 0.06 to 0.1 US$/kWh, 53% when the seawater salinity increased from 35,000 to 45,000 ppm, 2.5% when the seawater temperature decreased from 33 ℃ to 20 ℃, and 0.71% when the interest rate increased from 0% to 5%. Pumping fresh water from the Basra purification plant （located 175 km north of Umm Qasr） is 22.16 times the cost and 236.7% poorer quality than the fresh water produced by the RO plant.
文摘[ Objective] The aim was to find optimum reaction conditions for synthetic process of Vitamin C. [ Method] Vitamin C sodium was used as raw material to prepare vitamin C through acidification, separation, desalination, recovery and purification. The impact of reaction time, tempera-ture, feedstock molar ratio and water content on the yield of vitamin C were investigated in the experiment. [Result] The optimum reaction condi- tions for synthetic process of Vitamin C were as follows： in the acidification test, reaction time 120 min, temperature 20 -30 ℃, the molar ratio be-tween hydrochloric acid and Vitamin C sodium 1 ： 1 and water content 41.0%. Under the above condition, the purity and yield of vitamin C reach 99.80% and 94.74% respectively. [Conclusion] The process can decrease consumption, enhance quality and recover of the product, improve the environmental pollution, shorten processing periods and reduce production cost. Thus, the process is suitable for industrialization. Key words Vitamin C; Vitamin C sodium; Acidification; China
基金Supported by the National Natural Science Foundation of China(grant No.41171384,41271414 and 41301529)
文摘This study aimed to characterize constituents of phosphorus （P） fractionation as wel as reciprocities among factors in sediments of a freshwater shal ow lake. [Method] Surface sediment was discretely sampled at 24 sites through Van Veen grabs. Based on a modified sequential extraction scheme, P fractionation was determined as Fe/Al bound P （Fe/Al-P）, Ca bound P （Ca-P）, solute and re-ductive P （S/R-P） and organic P （OP）. Curve estimation and Pearson product-mo-ment correlation were employed for statistical analysis. [Result] Total P （TP） content ranged from 443 to 774 mg/kg. Inorganic P （IP） was the major component of TP, of which Ca-P was dominated with an average of 51%±9.7%. Average contents of P fractionation were in the fol owing order： Ca-P（51%） 〉 OP（29%） 〉 S/R-P（8%） 〉Fe/Al-P（7%）. The molar ratio of Fe to P was 11 - 20, close to the threshold value of P leaching. [Conclusion] In freshwater shal ow lakes, IP and Ca-P were prone to be relatively high, whereas Fe/Al-P was low compared with deep lakes. Occurrence of spatial y monotonic gradient indicated the primary causation of anthropogenic sources. Imminent sediment P liberation was also expected. Close associations a-mong TP, Fe/Al-P and Ca-P, implying that anthropogenic P was mainly bound to metals in particulates. Significant correlations of TOC and P fractionation highlighted endogenous mechanism and authigenic origin in sediments.
