Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon resources.However,the deposition and hydrocarbon evo...Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon resources.However,the deposition and hydrocarbon evolution process of ancient coal-bearing strata is characterized by multiple geological times,leading to obvious distinctions in their hydrocarbon generation potential,geological processes,and production,which affect the evaluation and exploration of hydrocarbon resources derived from coaly source rocks worldwide.This study aimed to identify the differences on oil-generated parent macerals and the production of oil generated from different coaly source rocks and through different oil generation processes.Integrating with the analysis of previous tectonic burial history and hydrocarbon generation history,high-temperature and high-pressure thermal simulation experiments,organic geochemistry,and organic petrology were performed on the Carboniferous-Permian(C-P)coaly source rocks in the Huanghua Depression,Bohai Bay Basin.The oil-generated parent macerals of coal's secondary oil generation process(SOGP)were mainly hydrogen-rich collotelinite,collodetrinite,sporinite,and cutinite,while the oil-generated parent macerals of tertiary oil generation process(TOGP)were the remaining small amount of hydrogen-rich collotelinite,sporinite,and cutinite,as well as dispersed soluble organic matter and unexhausted residual hydrocarbons.Compared with coal,the oil-generated parent macerals of coaly shale SOGP were mostly sporinite and cutinite.And part of hydrogen-poor vitrinite,lacking hydrocarbon-rich macerals,and macerals of the TOGP,in addition to some remaining cutinite and a small amount of crude oil and bitumen from SOGP contributed to the oil yield.The results indicated that the changes in oil yield had a good junction between SOGP and TOGP,both coal and coaly shale had higher SOGP aborted oil yield than TOGP starting yield,and coaly shale TOGP peak oil yield was lower than SOGP peak oil yield.There were significant differences in saturated hydrocarbon and aromatic parameters in coal and coaly shale.Coal SOGP was characterized by a lower Ts/Tm and C31-homohopane22S/(22S+22R)and a higher Pr/n C17compared to coal TOGP,while the aromatic parameter methyl dibenzothiophene ratio(MDR)exhibited coaly shale TOGP was higher than coaly shale SOGP than coaly TOGP than coaly SOGP,and coal trimethylnaphthalene ratio(TNR)was lower than coaly shale TNR.Thus,we established oil generation processes and discriminative plates.In this way,we distinguished the differences between oil generation parent maceral,oil generation time,and oil production of coaly source rocks,and therefore,we provided important support for the evaluation,prediction,and exploration of oil resources from global ancient coaly source rocks.展开更多
This study aimed to investigate the effect of oil processing technologies on the sensory qualities of sesame oils and to identify drivers of liking.Using a check-all-that-apply(CATA)question and a hedonic scale,150 co...This study aimed to investigate the effect of oil processing technologies on the sensory qualities of sesame oils and to identify drivers of liking.Using a check-all-that-apply(CATA)question and a hedonic scale,150 consumers evaluated the acceptability and sensory characteristics of 5 sesame oil samples including an aqueous extracted oil(S1),a cold-pressed oil(S2),two batches of screw-pressed oils(S3 and S5)and one crude sesame oil(S4).Solid-phase microextraction-gas chromatography-olfactometry-mass spectrometry(SPME-GC-O-MS)was used to identify odour-active compounds.The results showed that roasting,extraction techniques and filtration process influenced sensory perception and the acceptability of sesame oils.Consumers liked roasted sesame oils more than the cold-pressed sesame oil and liked the aqueous extracted sesame oil the most.Sensory attributes"sweet smell","mellow","roasted","nutty","persistent","high-intense flavour"and"cooked sesame seed flavour"were drivers of liking,while"green","raw sesame seed","rancid","woody"and"fishy"were drivers of disliking."Burnt"flavour was liked by some while disliked by others.Pyrazines contributed to roasted flavour;2-acetylpyrrole,acetophenone and furfural contributed to nutty flavour;2-pentyl-furan,5-methyl-2-furancarboxaldehyde,and 2-phenyl-2-butenal contributed to sweet odour in the roasted sesame seeds.Nonanal,hexanal,1-hexanol and ocimene were responsible for the"green"flavour perceived in the cold-pressed oil.This study provides valuable information for sesame manufacturers on how to improve the sensory qualities of sesame oils through process manipulation to meet the needs of diverse consumers.展开更多
Laboratory experiments were conducted to simulate oil weathering process, a medium to long term weathering process for 210-d, using samples collected from five different oil resources. Based on relative deviation and ...Laboratory experiments were conducted to simulate oil weathering process, a medium to long term weathering process for 210-d, using samples collected from five different oil resources. Based on relative deviation and repeatability limit analysis about indexes of these samples, the results show there had been significant changes in diagnostic ratios among the initial and weathered samples of different oils during this process. Changes of selected n-alkane diagnostic ratios of all oil samples displayed more obviously than diagnostic ratios of terpanes,steranes and PAHs in this process. Almost all selected diagnostic ratios of terpanes, steranes and PAHs can be efficiently used in tracking sources of hydrocarbon pollution, differentiating from the n-alkane diagnostic ratios.In these efficient diagnostic ratios, only four ratios maintained good stability in the weathering processes and are more suitable because their relative deviation(RSD) are lower than 5%.展开更多
Light olefins are important organic building blocks in the chemicals industry.The main low-carbon olefin production methods,such as catalytic cracking and steam cracking,have considerable room for improvement in their...Light olefins are important organic building blocks in the chemicals industry.The main low-carbon olefin production methods,such as catalytic cracking and steam cracking,have considerable room for improvement in their utilization of hydrocarbons.This review provides a thorough overview of recent studies on catalytic cracking,steam cracking,and the conversion of crude oil processes.To maximize the production of light olefins and reduce carbon emissions,the perceived benefits of various technologies are examined.Taking olefin generation and conversion as a link to expand upstream and downstream processes,a targeted catalytic cracking to olefins(TCO)process is proposed to meet current demands for the transformation of oil refining into chemical production.The main innovations of this process include a multiple feedstock supply,the development of medium-sized catalysts,and a diameter-transformed fluidizedbed reactor with different feeding schemes.In combination with other chemical processes,TCO is expected to play a critical role in enabling petroleum refining and chemical processes to achieve low carbon dioxide emissions.展开更多
Hydrogen network management is important to refineries. Various systematic management techniques have been developed to improve the efficiency of refinery hydrogen networks. However, existing methods all treat the hyd...Hydrogen network management is important to refineries. Various systematic management techniques have been developed to improve the efficiency of refinery hydrogen networks. However, existing methods all treat the hydrogen network separately. The tradeoff between hydrogen network cost and oil processing network benefit has not been explored in the hydrogen network management yet. A novel sensitivity analysis scheme is presented to take oil processing network into consideration. Oil processing unit which is sensitive to both oil processing networks and hydrogen networks is identified first. Then, sensitivity analysis of the unit around the operating point of oil processing networks and hydrogen networks is carried out. Finally, the overall optimal operating condition is obtained. An example of a real Chinese refinery demonstrates the effectiveness of the proposed analysis method.展开更多
Biodegradation usually obscures or even radically alters the original characteristics of oil biomarkers.The mixing of oil from multiple sources makes each source difficult to trace.Identifying the source of biodegrade...Biodegradation usually obscures or even radically alters the original characteristics of oil biomarkers.The mixing of oil from multiple sources makes each source difficult to trace.Identifying the source of biodegraded oil from multiple sources has always been a hard nut to crack.Rising to this challenge,in this study-we carried out a comprehensive investigation of biodegradation impacts,oil-source correlation,and oil charging history to trace the source and reveal the mixing process of biodegraded oil in the Toutunhe Formation(J_(2)t)in the eastern Junggar Basin,NW China.The oil of this area was biodegraded to different extent,consequently,many commonly used biomarker parameters(e.g.Pr/Ph,Pr/n C_(17))became less powerful for oil-source correlation.To address this problem,the resistance of many biomarkers to biodegradation was analyzed,and those of high bio resistance were selected to generate a more reliable oil-source correlation.The results revealed that biodegraded oil was a mixture of oil sourced from Lucaogou Formation(P_(2)l)and Xiaoquangou Formation(T_(2-3)xq).Core sample observation,microscopic fluorescent analysis and fluid inclusion analysis were combined to analyze comprehensively oil charging history.The analysis of accumulation process exhibited that the existing oil in J_(2)t was a mixture originated from the P_(2)l and T_(2-3)xq source rocks in two separate charging stages when it underwent a complicated process of charging,biodegradation,recharging and mixing.展开更多
This article summarizes the block process flow scheme for the 8.0 Mt/a refining project at Hainan Refining and Chemical Company, Ltd., highlighting a green route for processing sour heavy oils, and the enlarged scale ...This article summarizes the block process flow scheme for the 8.0 Mt/a refining project at Hainan Refining and Chemical Company, Ltd., highlighting a green route for processing sour heavy oils, and the enlarged scale of production with Chinese content. The refinery is targeted at hydrotreating of process streams, integration and intensified design of process units, clean gasoline and diesel production, centralized recovery and utilization of light ends and optimization of sulphur recovery systems.展开更多
The similarities and differences of essential oil components in the raw ingredients of Ephedra (RIE) and processed products of Ephedra obtained by stir-baking with honey or stir-baking without any supplements were a...The similarities and differences of essential oil components in the raw ingredients of Ephedra (RIE) and processed products of Ephedra obtained by stir-baking with honey or stir-baking without any supplements were analyzed by GC-MS.Wet distillation (WD) and supercritical fluid extraction (SFE) were used to extract essential oil components from the samples.Total 48,57 and 48 compounds were found in the extracted essential oils using WD from RIE,the products obtained by stir-baking with honey from Ephedra (SBHE) and the products obtained by stir-baking without any supplements from Ephedra (SBE),respectively whereas total 22,36 and 28 compounds were identified in the extracted essential oils using SPE from these three samples,respectively.In addition,14 and 9 new compounds were found in the essential oils extracted using WD from SBHE and SBE,whereas 15 and 23 new compounds were found in the essential oils extracted by SFE from SBHE and SBE,respectively.The composition and concentration of the essential oil components in the processed products were significantly different from RIE.Such changes in essential oil components might affect drug actions,which is dependent on the manner in which the sample is processed.The findings in this study may shed some lights on the understanding and further exploration of Ephedra processing.展开更多
Objectives:Polycyclic aromatic hydrocarbons(PAHs)and 3-monochloropropane-1,2-diol ester(3-MCPDE)were studied in camellia oil.It is important to study the changes in the content of PAHs and 3-MCPDE at different refinin...Objectives:Polycyclic aromatic hydrocarbons(PAHs)and 3-monochloropropane-1,2-diol ester(3-MCPDE)were studied in camellia oil.It is important to study the changes in the content of PAHs and 3-MCPDE at different refining stages(from crude oil to the final refined oil product)to elucidate the influence of the refining procedures on their change.Materials and methods:The PAHs and 3-MCPDE in camellia oil from different refining stages(from crude oil to the product)of a plant were analyzed by gas chromatography–mass spectrometry and calculated by the internal standard method.Results:The overall PAH content was(79.64±2.43)μg/kg in crude camellia oil.After refining treatment,the PAH content decreased to(18.75±0.55)μg/kg.The 3-MCPDE content increased during the refining process from 0 mg/kg in the crude oil to 4.62 mg/kg in the refined oil product.Conclusions:This is the first study to simultaneously monitor changes in both PAH and 3-MCPDE contents during the production of camellia oil.These results confirmed the effectiveness of the refining method on PAH removal and the increase in 3-MCPDE at high temperature.It is suggested that novel processing methods or refining parameters need further optimization to decrease the overall concentrations of PAHs and 3-MCPDE in camellia oil.展开更多
Naphthenic acids are a complex class of thousands of naturally occurring aliphatic and alicyclic carboxylic acids found in oil sands bitumen and in the wastewater generated from bitumen processing. Dozens of analytica...Naphthenic acids are a complex class of thousands of naturally occurring aliphatic and alicyclic carboxylic acids found in oil sands bitumen and in the wastewater generated from bitumen processing. Dozens of analytical methods have been developed for the semiquantification of total naphthenic acids in water samples. However, different methods can give different results, prompting investigation into the comparability of the many methods. A review of important methodological features for analyzing total naphthenic acids is presented and informs the design of future standard methods for the semi- quantification of total naphthenic acids using mass spectrometry. The design considerations presented are a synthesis of discussions from an Environment and Climate Change Canada (ECCC) led taskforce of 10 laboratory experts from government, industry and academia during April 2016 and subsequent discussions between University of British Columbia and ECCC representatives. Matters considered are: extraction method, solvent, pH, and temperature; analysis instrumentation and resolution; choice of calibration standards; use of surrogate and internal standards; and use of online or offline separation prior to analysis. The design considerations are amenable to both time-of-flight and Orbitrap mass spectrometers.展开更多
The objective of this research was to develop a novel self-lubricating coating on an AA6061 aluminum alloy.Three coatings were prepared by the plasma electrolytic oxidation(PEO) process using 50-, 500-, and 1000-Hz ...The objective of this research was to develop a novel self-lubricating coating on an AA6061 aluminum alloy.Three coatings were prepared by the plasma electrolytic oxidation(PEO) process using 50-, 500-, and 1000-Hz pulsed direct current, respectively. The as-deposited coatings were then post-treated using two different methods, viz., ultrasonic vibration-aided vacuum oil impregnation(UVOI) and oil impregnation under ambient pressure(OIAP). After posttreatment, an oil-containing, self-lubricating top layer was formed on the coatings. The effects of the coatings' surface morphologies and structures on their oil-holding capabilities were discussed. The results revealed that coatings prepared with higher frequency had a greater oil-holding capacity using OIAP post-treatment, while those prepared with lower frequency had a greater oil-containing capability using UVOI post-treatment. These phenomena are related to the morphologies of the coatings produced with various current modes. The tribological properties of the coatings before and after post-treatments were investigated by pin-on-disc sliding wear tests. Due to the formation of a lubricant-containing top layer, the post-treatment coatings had a lower friction coefficient and improved wear resistance compared with the asdeposited coatings. In addition, the coatings after UVOI treatment had better wear performance than those post-treated using the OIAP process. Among all coatings, the coating produced with a 50-Hz pulsed current followed by UVOI posttreatment achieved the lowest friction coefficient(0.03) and best wear resistance when sliding against a Si3N4 ceramic counterface. This study indicates that a novel self-lubricating coating can be prepared by a PEO process combined with vacuum oil impregnation post-treatment.展开更多
基金supported by the Certificate of National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2016ZX05006007-004)the National Natural Science Foundation of China(Nos.42172145,42072130)。
文摘Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon resources.However,the deposition and hydrocarbon evolution process of ancient coal-bearing strata is characterized by multiple geological times,leading to obvious distinctions in their hydrocarbon generation potential,geological processes,and production,which affect the evaluation and exploration of hydrocarbon resources derived from coaly source rocks worldwide.This study aimed to identify the differences on oil-generated parent macerals and the production of oil generated from different coaly source rocks and through different oil generation processes.Integrating with the analysis of previous tectonic burial history and hydrocarbon generation history,high-temperature and high-pressure thermal simulation experiments,organic geochemistry,and organic petrology were performed on the Carboniferous-Permian(C-P)coaly source rocks in the Huanghua Depression,Bohai Bay Basin.The oil-generated parent macerals of coal's secondary oil generation process(SOGP)were mainly hydrogen-rich collotelinite,collodetrinite,sporinite,and cutinite,while the oil-generated parent macerals of tertiary oil generation process(TOGP)were the remaining small amount of hydrogen-rich collotelinite,sporinite,and cutinite,as well as dispersed soluble organic matter and unexhausted residual hydrocarbons.Compared with coal,the oil-generated parent macerals of coaly shale SOGP were mostly sporinite and cutinite.And part of hydrogen-poor vitrinite,lacking hydrocarbon-rich macerals,and macerals of the TOGP,in addition to some remaining cutinite and a small amount of crude oil and bitumen from SOGP contributed to the oil yield.The results indicated that the changes in oil yield had a good junction between SOGP and TOGP,both coal and coaly shale had higher SOGP aborted oil yield than TOGP starting yield,and coaly shale TOGP peak oil yield was lower than SOGP peak oil yield.There were significant differences in saturated hydrocarbon and aromatic parameters in coal and coaly shale.Coal SOGP was characterized by a lower Ts/Tm and C31-homohopane22S/(22S+22R)and a higher Pr/n C17compared to coal TOGP,while the aromatic parameter methyl dibenzothiophene ratio(MDR)exhibited coaly shale TOGP was higher than coaly shale SOGP than coaly TOGP than coaly SOGP,and coal trimethylnaphthalene ratio(TNR)was lower than coaly shale TNR.Thus,we established oil generation processes and discriminative plates.In this way,we distinguished the differences between oil generation parent maceral,oil generation time,and oil production of coaly source rocks,and therefore,we provided important support for the evaluation,prediction,and exploration of oil resources from global ancient coaly source rocks.
基金supported by the China Agricultural Research System(CARS14-1-29)Henan University of Technology High-Level Talents Fund(2018BS060)。
文摘This study aimed to investigate the effect of oil processing technologies on the sensory qualities of sesame oils and to identify drivers of liking.Using a check-all-that-apply(CATA)question and a hedonic scale,150 consumers evaluated the acceptability and sensory characteristics of 5 sesame oil samples including an aqueous extracted oil(S1),a cold-pressed oil(S2),two batches of screw-pressed oils(S3 and S5)and one crude sesame oil(S4).Solid-phase microextraction-gas chromatography-olfactometry-mass spectrometry(SPME-GC-O-MS)was used to identify odour-active compounds.The results showed that roasting,extraction techniques and filtration process influenced sensory perception and the acceptability of sesame oils.Consumers liked roasted sesame oils more than the cold-pressed sesame oil and liked the aqueous extracted sesame oil the most.Sensory attributes"sweet smell","mellow","roasted","nutty","persistent","high-intense flavour"and"cooked sesame seed flavour"were drivers of liking,while"green","raw sesame seed","rancid","woody"and"fishy"were drivers of disliking."Burnt"flavour was liked by some while disliked by others.Pyrazines contributed to roasted flavour;2-acetylpyrrole,acetophenone and furfural contributed to nutty flavour;2-pentyl-furan,5-methyl-2-furancarboxaldehyde,and 2-phenyl-2-butenal contributed to sweet odour in the roasted sesame seeds.Nonanal,hexanal,1-hexanol and ocimene were responsible for the"green"flavour perceived in the cold-pressed oil.This study provides valuable information for sesame manufacturers on how to improve the sensory qualities of sesame oils through process manipulation to meet the needs of diverse consumers.
基金The National Natural Science Foundation of China under contract No.41206089Project of on-site sediment microbial remediation of public area of central Bohai Sea,North China Sea Branch of State Oceanic Administration under contract No.QDZC20150420-002Program of Science and Technology Service Network Initiative,Chinese Academy of Sciences under contract No.KFJ-EW-STS-127
文摘Laboratory experiments were conducted to simulate oil weathering process, a medium to long term weathering process for 210-d, using samples collected from five different oil resources. Based on relative deviation and repeatability limit analysis about indexes of these samples, the results show there had been significant changes in diagnostic ratios among the initial and weathered samples of different oils during this process. Changes of selected n-alkane diagnostic ratios of all oil samples displayed more obviously than diagnostic ratios of terpanes,steranes and PAHs in this process. Almost all selected diagnostic ratios of terpanes, steranes and PAHs can be efficiently used in tracking sources of hydrocarbon pollution, differentiating from the n-alkane diagnostic ratios.In these efficient diagnostic ratios, only four ratios maintained good stability in the weathering processes and are more suitable because their relative deviation(RSD) are lower than 5%.
基金financially supported by a research grant from the National Key Research and Development Program of China(2021YFA1501204)China Petroleum and Chemical Corporation(Sinopec Corp.),China(ST22001)。
文摘Light olefins are important organic building blocks in the chemicals industry.The main low-carbon olefin production methods,such as catalytic cracking and steam cracking,have considerable room for improvement in their utilization of hydrocarbons.This review provides a thorough overview of recent studies on catalytic cracking,steam cracking,and the conversion of crude oil processes.To maximize the production of light olefins and reduce carbon emissions,the perceived benefits of various technologies are examined.Taking olefin generation and conversion as a link to expand upstream and downstream processes,a targeted catalytic cracking to olefins(TCO)process is proposed to meet current demands for the transformation of oil refining into chemical production.The main innovations of this process include a multiple feedstock supply,the development of medium-sized catalysts,and a diameter-transformed fluidizedbed reactor with different feeding schemes.In combination with other chemical processes,TCO is expected to play a critical role in enabling petroleum refining and chemical processes to achieve low carbon dioxide emissions.
基金financial supported by National Natural Science Foundation of China(No.20409205 & 60421002)National High Technology Research and Development Program of China(No.2007AA04Z191 & 2007AA040702)
文摘Hydrogen network management is important to refineries. Various systematic management techniques have been developed to improve the efficiency of refinery hydrogen networks. However, existing methods all treat the hydrogen network separately. The tradeoff between hydrogen network cost and oil processing network benefit has not been explored in the hydrogen network management yet. A novel sensitivity analysis scheme is presented to take oil processing network into consideration. Oil processing unit which is sensitive to both oil processing networks and hydrogen networks is identified first. Then, sensitivity analysis of the unit around the operating point of oil processing networks and hydrogen networks is carried out. Finally, the overall optimal operating condition is obtained. An example of a real Chinese refinery demonstrates the effectiveness of the proposed analysis method.
基金supported by a grant from National Science Foundation for Young Scientists of China(Grant No.41702143)Natural Science Foundation of Shandong Province of China(ZR2016DL06+3 种基金ZR2017LD005)the Fundamental Research Funds for the Central Universities(17CX02006A)the Foundation of Shandong Provincial Key Laboratory of Depositional Mineralization&Sedimentary Mineral(DMSM2017063)the major science and technology project of Xinjiang Petroleum Administration Bureau of CNPC(2017E-0401)。
文摘Biodegradation usually obscures or even radically alters the original characteristics of oil biomarkers.The mixing of oil from multiple sources makes each source difficult to trace.Identifying the source of biodegraded oil from multiple sources has always been a hard nut to crack.Rising to this challenge,in this study-we carried out a comprehensive investigation of biodegradation impacts,oil-source correlation,and oil charging history to trace the source and reveal the mixing process of biodegraded oil in the Toutunhe Formation(J_(2)t)in the eastern Junggar Basin,NW China.The oil of this area was biodegraded to different extent,consequently,many commonly used biomarker parameters(e.g.Pr/Ph,Pr/n C_(17))became less powerful for oil-source correlation.To address this problem,the resistance of many biomarkers to biodegradation was analyzed,and those of high bio resistance were selected to generate a more reliable oil-source correlation.The results revealed that biodegraded oil was a mixture of oil sourced from Lucaogou Formation(P_(2)l)and Xiaoquangou Formation(T_(2-3)xq).Core sample observation,microscopic fluorescent analysis and fluid inclusion analysis were combined to analyze comprehensively oil charging history.The analysis of accumulation process exhibited that the existing oil in J_(2)t was a mixture originated from the P_(2)l and T_(2-3)xq source rocks in two separate charging stages when it underwent a complicated process of charging,biodegradation,recharging and mixing.
文摘This article summarizes the block process flow scheme for the 8.0 Mt/a refining project at Hainan Refining and Chemical Company, Ltd., highlighting a green route for processing sour heavy oils, and the enlarged scale of production with Chinese content. The refinery is targeted at hydrotreating of process streams, integration and intensified design of process units, clean gasoline and diesel production, centralized recovery and utilization of light ends and optimization of sulphur recovery systems.
基金State Projects of the Eleventh-Five-year Plan (Grant No.2006BAI09B06-08-05)
文摘The similarities and differences of essential oil components in the raw ingredients of Ephedra (RIE) and processed products of Ephedra obtained by stir-baking with honey or stir-baking without any supplements were analyzed by GC-MS.Wet distillation (WD) and supercritical fluid extraction (SFE) were used to extract essential oil components from the samples.Total 48,57 and 48 compounds were found in the extracted essential oils using WD from RIE,the products obtained by stir-baking with honey from Ephedra (SBHE) and the products obtained by stir-baking without any supplements from Ephedra (SBE),respectively whereas total 22,36 and 28 compounds were identified in the extracted essential oils using SPE from these three samples,respectively.In addition,14 and 9 new compounds were found in the essential oils extracted using WD from SBHE and SBE,whereas 15 and 23 new compounds were found in the essential oils extracted by SFE from SBHE and SBE,respectively.The composition and concentration of the essential oil components in the processed products were significantly different from RIE.Such changes in essential oil components might affect drug actions,which is dependent on the manner in which the sample is processed.The findings in this study may shed some lights on the understanding and further exploration of Ephedra processing.
基金funded by the Key Research and Development Program of Guangdong Province(No.2019B020212001)Zhejiang Basic Public Welfare Research Project(LGN19C200003)+1 种基金the National Key Research and Development Program of China(2018YFC1603600)National Natural Science Foundation of China(No.31871884).
文摘Objectives:Polycyclic aromatic hydrocarbons(PAHs)and 3-monochloropropane-1,2-diol ester(3-MCPDE)were studied in camellia oil.It is important to study the changes in the content of PAHs and 3-MCPDE at different refining stages(from crude oil to the final refined oil product)to elucidate the influence of the refining procedures on their change.Materials and methods:The PAHs and 3-MCPDE in camellia oil from different refining stages(from crude oil to the product)of a plant were analyzed by gas chromatography–mass spectrometry and calculated by the internal standard method.Results:The overall PAH content was(79.64±2.43)μg/kg in crude camellia oil.After refining treatment,the PAH content decreased to(18.75±0.55)μg/kg.The 3-MCPDE content increased during the refining process from 0 mg/kg in the crude oil to 4.62 mg/kg in the refined oil product.Conclusions:This is the first study to simultaneously monitor changes in both PAH and 3-MCPDE contents during the production of camellia oil.These results confirmed the effectiveness of the refining method on PAH removal and the increase in 3-MCPDE at high temperature.It is suggested that novel processing methods or refining parameters need further optimization to decrease the overall concentrations of PAHs and 3-MCPDE in camellia oil.
文摘Naphthenic acids are a complex class of thousands of naturally occurring aliphatic and alicyclic carboxylic acids found in oil sands bitumen and in the wastewater generated from bitumen processing. Dozens of analytical methods have been developed for the semiquantification of total naphthenic acids in water samples. However, different methods can give different results, prompting investigation into the comparability of the many methods. A review of important methodological features for analyzing total naphthenic acids is presented and informs the design of future standard methods for the semi- quantification of total naphthenic acids using mass spectrometry. The design considerations presented are a synthesis of discussions from an Environment and Climate Change Canada (ECCC) led taskforce of 10 laboratory experts from government, industry and academia during April 2016 and subsequent discussions between University of British Columbia and ECCC representatives. Matters considered are: extraction method, solvent, pH, and temperature; analysis instrumentation and resolution; choice of calibration standards; use of surrogate and internal standards; and use of online or offline separation prior to analysis. The design considerations are amenable to both time-of-flight and Orbitrap mass spectrometers.
基金financially supported by the National Natural Science Foundation of China (No. 51301153)the National Undergraduate Training Programs for Innovation and Entrepreneurship of China (201410345022)
文摘The objective of this research was to develop a novel self-lubricating coating on an AA6061 aluminum alloy.Three coatings were prepared by the plasma electrolytic oxidation(PEO) process using 50-, 500-, and 1000-Hz pulsed direct current, respectively. The as-deposited coatings were then post-treated using two different methods, viz., ultrasonic vibration-aided vacuum oil impregnation(UVOI) and oil impregnation under ambient pressure(OIAP). After posttreatment, an oil-containing, self-lubricating top layer was formed on the coatings. The effects of the coatings' surface morphologies and structures on their oil-holding capabilities were discussed. The results revealed that coatings prepared with higher frequency had a greater oil-holding capacity using OIAP post-treatment, while those prepared with lower frequency had a greater oil-containing capability using UVOI post-treatment. These phenomena are related to the morphologies of the coatings produced with various current modes. The tribological properties of the coatings before and after post-treatments were investigated by pin-on-disc sliding wear tests. Due to the formation of a lubricant-containing top layer, the post-treatment coatings had a lower friction coefficient and improved wear resistance compared with the asdeposited coatings. In addition, the coatings after UVOI treatment had better wear performance than those post-treated using the OIAP process. Among all coatings, the coating produced with a 50-Hz pulsed current followed by UVOI posttreatment achieved the lowest friction coefficient(0.03) and best wear resistance when sliding against a Si3N4 ceramic counterface. This study indicates that a novel self-lubricating coating can be prepared by a PEO process combined with vacuum oil impregnation post-treatment.