The revaluation of medicinal plants in the veterinary pharmacopoeia is essential for the development of livestock in Burkina Faso. In order to justify the use of C. sesamoides and S. hermonthica in the treatment of ga...The revaluation of medicinal plants in the veterinary pharmacopoeia is essential for the development of livestock in Burkina Faso. In order to justify the use of C. sesamoides and S. hermonthica in the treatment of gastrointestinal parasitosis of small ruminants, a quantification of phenolic compounds as well as antioxidant activity and acute toxicité evaluation of both plants were performed. Acute toxicity was evaluated by administering a single dose of 2000 mg/kg body weight of aqueous extract of both plants to mice. The highest total polyphenol content for C. sesamo?des was obtained in the ethyl acetate fraction with 47.236 ± 2.57 mgEAG/100mg while that of S. hermonthica was 74.871 ± 2.57 mgEAG/100mg obtained with the n-butanol Fraction. The dichloromethane extract of S. hermonthica obtained the highest total flavonoid content with 7.31 ± 0.48 mgEQ/100 while the highest total flavonoid content of C. sesamo?des was obtained with ethyl acetate fraction with 5.4273 ± 0.35 mgEQ/100mg. The aqueous extract of C. sesamo?des obtained the highest content of condensed tannins with 3.028 ± 0.13 mgEAT/100mg. Both plant’s extracts did not show any signs of toxicity in NMRI mice after administration of the dose of 2000 mg/kg. The antioxidant activity by DPPH, FRAP and ABTS methods was good compared to those of Quercetin and Trolox taken as standard.展开更多
Geological storage of acid gas has been identified as a promising approach to reduce atmospheric carbon dioxide(CO_(2)),hydrogen sulfide(H_(2)S)and alleviate public concern resulting from the sour gas production.A goo...Geological storage of acid gas has been identified as a promising approach to reduce atmospheric carbon dioxide(CO_(2)),hydrogen sulfide(H_(2)S)and alleviate public concern resulting from the sour gas production.A good understanding of the relative permeability and capillary pressure characteristics is crucial to predict the process of acid gas injection and migration.The prediction of injection and redistribution of acid gas is important to determine storage capacity,formation pressure,plume extent,shape,and leakage potential.Herein,the existing experimental data and theoretical models were reviewed to gain a better understanding of the issue how the H_(2)S content affects gas density,gas viscosity,interfacial tension,wettability,relative permeability and capillary pressure characteristics of acid gas/brine/rock systems.The densities and viscosities of the acid gas with different H_(2)S mole fractions are both temperature-and pressure-dependent,which vary among the gas,liquid and supercritical phases.Water/acid gas interfacial tension decreases strongly with increasing H_(2)S content.For mica and clean quartz,water contact angle increases with increasing H_(2)S mole fraction.In particular,wettability reversal of mica to a H_(2)S-wet behavior occurs in the presence of dense H_(2)S.The capillary pressure increases with decreasing contact angle.At a given saturation,the relative permeability of a fluid is higher when the fluid is nonwetting.The capillary pressure decreases with decreasing interfacial tension at a given saturation.However,the existing datasets do not show a consistent link between capillary number and relative permeability.The capillary pressure decreases with increasing H_(2)S mole fraction.However,there is no consensus on the effect of the H_(2)S content on the relative permeability curves.This may be due to the limited availability of the relative permeability and capillary pressure data for acid gas/brine/rock systems;thus,more experimental measurements are required.展开更多
In the present work, the effects of chemical compositions on the hydrogen blistering and hydrogen induced cracking of A350LF2 steel with different S contents were studied. Four types of A350LF2 steels were evaluated b...In the present work, the effects of chemical compositions on the hydrogen blistering and hydrogen induced cracking of A350LF2 steel with different S contents were studied. Four types of A350LF2 steels were evaluated by immersing samples in H2S-saturated NACE solution. The hydrogen blistering, crack length rate(CLR), crack thickness rate(CTR) and crack sensitivity rate(CSR) were evaluated. The results show that there are many hydrogen blisters on the sample surface with S content of 0.021%, a few on the sample surface with S content of 0.019% and 0.012% and no one on the surface with S content of 0.002%. There were 12, 2 and 1 strips of cracks of longer than 0.3 mm on the evaluated cross sections with S content of 0.021%, 0.019% and 0.012%, respectively. There was no any crack in the sample with 0.002% S. The corrosion rate was also evaluated. The S content has no obvious influence on the corrosion rate.展开更多
Cu2ZnSnS4 thin films were prepared by cosputtering with Cu(or Cu2S),ZnS and SnS2 targets in this study.S amount in the precursor of Cu2ZnSnS4 thin film was verified by using Cu or Cu2S target.The effect of S amount in...Cu2ZnSnS4 thin films were prepared by cosputtering with Cu(or Cu2S),ZnS and SnS2 targets in this study.S amount in the precursor of Cu2ZnSnS4 thin film was verified by using Cu or Cu2S target.The effect of S amount in the precursor on the microstructure and element distribution of Cu2ZnSnS4 thin film was discussed.It was found that S content is sufficient in the precursor thin film using Cu2 S instead of Cu target.The microstructure,composition homogeneity,and secondary phase formation of the Cu2ZnSnS4 thin film are seriously affected by S amount in the precursor thin film.Namely,sufficient S can improve the crystallization and orientation of the precursor thin film and enhance the compactness as well as composition homogeneity of the Cu2ZnSnS4 thin film after sulfurization.Moreover,the secondary phase formation in Cu2ZnSnS4 thin film can be greatly inhibited by increasing S content in the precursor thin film.展开更多
The corrosion behavior of the 110S tube steel in the environments of high H2 S and CO2 content was inves- tigated by using a high-temperature and high-pressure autoclave, and the corrosion products were characterized ...The corrosion behavior of the 110S tube steel in the environments of high H2 S and CO2 content was inves- tigated by using a high-temperature and high-pressure autoclave, and the corrosion products were characterized by scanning electron microscopy and X ray diffraction technique. The results showed that all of the corrosion products under the test conditions mainly consisted of different types of iron sulfides such as pyrrhotite of Fe0.95 S, mackinaw- ite of FeS0.9, Fe0. 985 S and FeS, and the absence of iron carbonate in the corrosion scales indicated that the corrosion process was controlled by H2S corrosion. The corrosion rate of the 110S steel decreased firstly and then increased with the rising of temperature. The minimum corrosion rate occurred at 110 ℃. When the H2 S partial pressure PH2s below 9 MPa, the corrosion rate declined with the increase of PH2s. While over 9 MPa, a higher PH2s resulted in a faster corrosion process. With the increasing of the CO2 partial pressure, the corrosion rate had an increasing trend. The morphologies of the corrosion scales had a good accordance with the corrosion rates.展开更多
This paper aims to examine the specific ways in which China's exports of manufactured goods to the United States boost the U.S. job market. Using the OECD STAN Bilateral Trade Database by Industry and End-use Categor...This paper aims to examine the specific ways in which China's exports of manufactured goods to the United States boost the U.S. job market. Using the OECD STAN Bilateral Trade Database by Industry and End-use Category to calculate the share of U.S. intermediate products used in the manufactured goods China exports to the U.S., this paper finds that the "U.S. content" in China's exports of manufactured goods to the U.S. increases with the technology content of the goods and shows a decreasing trend over time. From 2006 to 2010, the average "US. content" in China's exports of manufactured goods to the U.S. was 1%, and such content in China's exports of high-end manufactured goods was 1.6%. On this basis and using the employment-output ratio in the U.S. Employment Demand Matrix, this paper concludes that as many as 1.71 million jobs have been created by the U.S. intermediate products used in China's exports of manufactured goods to the U.S. during the same period. Thus, the development of Sino-U.S. trade has a positive impact on the job market in the U.S.. By contrast, instead of improving the employment situation in the U.S., the RMB appreciation proposed by the U.S. might even have a negative effect.展开更多
文摘The revaluation of medicinal plants in the veterinary pharmacopoeia is essential for the development of livestock in Burkina Faso. In order to justify the use of C. sesamoides and S. hermonthica in the treatment of gastrointestinal parasitosis of small ruminants, a quantification of phenolic compounds as well as antioxidant activity and acute toxicité evaluation of both plants were performed. Acute toxicity was evaluated by administering a single dose of 2000 mg/kg body weight of aqueous extract of both plants to mice. The highest total polyphenol content for C. sesamo?des was obtained in the ethyl acetate fraction with 47.236 ± 2.57 mgEAG/100mg while that of S. hermonthica was 74.871 ± 2.57 mgEAG/100mg obtained with the n-butanol Fraction. The dichloromethane extract of S. hermonthica obtained the highest total flavonoid content with 7.31 ± 0.48 mgEQ/100 while the highest total flavonoid content of C. sesamo?des was obtained with ethyl acetate fraction with 5.4273 ± 0.35 mgEQ/100mg. The aqueous extract of C. sesamo?des obtained the highest content of condensed tannins with 3.028 ± 0.13 mgEAT/100mg. Both plant’s extracts did not show any signs of toxicity in NMRI mice after administration of the dose of 2000 mg/kg. The antioxidant activity by DPPH, FRAP and ABTS methods was good compared to those of Quercetin and Trolox taken as standard.
基金the National Natural Science Foundation of China(Grant Nos.41872210 and 41274111)the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering(Grant No.Z018002)。
文摘Geological storage of acid gas has been identified as a promising approach to reduce atmospheric carbon dioxide(CO_(2)),hydrogen sulfide(H_(2)S)and alleviate public concern resulting from the sour gas production.A good understanding of the relative permeability and capillary pressure characteristics is crucial to predict the process of acid gas injection and migration.The prediction of injection and redistribution of acid gas is important to determine storage capacity,formation pressure,plume extent,shape,and leakage potential.Herein,the existing experimental data and theoretical models were reviewed to gain a better understanding of the issue how the H_(2)S content affects gas density,gas viscosity,interfacial tension,wettability,relative permeability and capillary pressure characteristics of acid gas/brine/rock systems.The densities and viscosities of the acid gas with different H_(2)S mole fractions are both temperature-and pressure-dependent,which vary among the gas,liquid and supercritical phases.Water/acid gas interfacial tension decreases strongly with increasing H_(2)S content.For mica and clean quartz,water contact angle increases with increasing H_(2)S mole fraction.In particular,wettability reversal of mica to a H_(2)S-wet behavior occurs in the presence of dense H_(2)S.The capillary pressure increases with decreasing contact angle.At a given saturation,the relative permeability of a fluid is higher when the fluid is nonwetting.The capillary pressure decreases with decreasing interfacial tension at a given saturation.However,the existing datasets do not show a consistent link between capillary number and relative permeability.The capillary pressure decreases with increasing H_(2)S mole fraction.However,there is no consensus on the effect of the H_(2)S content on the relative permeability curves.This may be due to the limited availability of the relative permeability and capillary pressure data for acid gas/brine/rock systems;thus,more experimental measurements are required.
文摘In the present work, the effects of chemical compositions on the hydrogen blistering and hydrogen induced cracking of A350LF2 steel with different S contents were studied. Four types of A350LF2 steels were evaluated by immersing samples in H2S-saturated NACE solution. The hydrogen blistering, crack length rate(CLR), crack thickness rate(CTR) and crack sensitivity rate(CSR) were evaluated. The results show that there are many hydrogen blisters on the sample surface with S content of 0.021%, a few on the sample surface with S content of 0.019% and 0.012% and no one on the surface with S content of 0.002%. There were 12, 2 and 1 strips of cracks of longer than 0.3 mm on the evaluated cross sections with S content of 0.021%, 0.019% and 0.012%, respectively. There was no any crack in the sample with 0.002% S. The corrosion rate was also evaluated. The S content has no obvious influence on the corrosion rate.
基金financially supported by the Foundation of Special Scientific Research Institutes(No.2013EG115002)the Innovation Foundation of General Research Institute for Nonferrous Metals(No.52215).
文摘Cu2ZnSnS4 thin films were prepared by cosputtering with Cu(or Cu2S),ZnS and SnS2 targets in this study.S amount in the precursor of Cu2ZnSnS4 thin film was verified by using Cu or Cu2S target.The effect of S amount in the precursor on the microstructure and element distribution of Cu2ZnSnS4 thin film was discussed.It was found that S content is sufficient in the precursor thin film using Cu2 S instead of Cu target.The microstructure,composition homogeneity,and secondary phase formation of the Cu2ZnSnS4 thin film are seriously affected by S amount in the precursor thin film.Namely,sufficient S can improve the crystallization and orientation of the precursor thin film and enhance the compactness as well as composition homogeneity of the Cu2ZnSnS4 thin film after sulfurization.Moreover,the secondary phase formation in Cu2ZnSnS4 thin film can be greatly inhibited by increasing S content in the precursor thin film.
基金Sponsored by Key National Science and Technology Specific Projects of China(2008ZX05017-002)
文摘The corrosion behavior of the 110S tube steel in the environments of high H2 S and CO2 content was inves- tigated by using a high-temperature and high-pressure autoclave, and the corrosion products were characterized by scanning electron microscopy and X ray diffraction technique. The results showed that all of the corrosion products under the test conditions mainly consisted of different types of iron sulfides such as pyrrhotite of Fe0.95 S, mackinaw- ite of FeS0.9, Fe0. 985 S and FeS, and the absence of iron carbonate in the corrosion scales indicated that the corrosion process was controlled by H2S corrosion. The corrosion rate of the 110S steel decreased firstly and then increased with the rising of temperature. The minimum corrosion rate occurred at 110 ℃. When the H2 S partial pressure PH2s below 9 MPa, the corrosion rate declined with the increase of PH2s. While over 9 MPa, a higher PH2s resulted in a faster corrosion process. With the increasing of the CO2 partial pressure, the corrosion rate had an increasing trend. The morphologies of the corrosion scales had a good accordance with the corrosion rates.
基金supported by the Fundamental Research Funds for the Central Universitiesthe Research Funds of Renmin University of China(Grant No.13XNI006)
文摘This paper aims to examine the specific ways in which China's exports of manufactured goods to the United States boost the U.S. job market. Using the OECD STAN Bilateral Trade Database by Industry and End-use Category to calculate the share of U.S. intermediate products used in the manufactured goods China exports to the U.S., this paper finds that the "U.S. content" in China's exports of manufactured goods to the U.S. increases with the technology content of the goods and shows a decreasing trend over time. From 2006 to 2010, the average "US. content" in China's exports of manufactured goods to the U.S. was 1%, and such content in China's exports of high-end manufactured goods was 1.6%. On this basis and using the employment-output ratio in the U.S. Employment Demand Matrix, this paper concludes that as many as 1.71 million jobs have been created by the U.S. intermediate products used in China's exports of manufactured goods to the U.S. during the same period. Thus, the development of Sino-U.S. trade has a positive impact on the job market in the U.S.. By contrast, instead of improving the employment situation in the U.S., the RMB appreciation proposed by the U.S. might even have a negative effect.