The surface nature of fresh Mo2N/Al2O3, Mo2C/Al2O3 and/MoP/Al2O3 catalysts, which were synthesized directly in the IR cell to avoid passivation, were characterized by in situ IR spectroscopy with CO as a probe molecul...The surface nature of fresh Mo2N/Al2O3, Mo2C/Al2O3 and/MoP/Al2O3 catalysts, which were synthesized directly in the IR cell to avoid passivation, were characterized by in situ IR spectroscopy with CO as a probe molecule. CO adsorbed on fresh catalysts showed characteristic IR bands at 2045 cm-1 for Mo2N/Al2O3 catalyst, 2054 cm-1 for MozC/Al2O3 catalyst and 2037 cm-1 for MoP/Al2O3 catalyst, respectively. A strong band at 2200 cm-1 for Mo2N/Al2O3 catalyst, which could be ascribed to NCO species formed when CO reacted upon surface active nitrogen atoms, and a weak band at 2196 cm-1 for Mo2C/Al2O3 catalyst, which could be attributed to CCO species, were also detected. CO adsorbed on fresh Mo2N/Al2O3 catalyst, Mo2C/Al2O3 catalyst and MoP/Al2O3 catalyst, showed strong molecular adsorption, just like noble metals. Our experimental results are bolstered by direct IR evidence demonstrating the similarity in surface electronic property between the fresh Mo2N/Al2O3, Mo2C/Al2O3 and MoP/Al2O3 catalysts and noble metals.展开更多
Three representative sulfide ore samples were collected from typical metal mines,and their corresponding pre-oxidized products were obtained under nature environment.The thermal behaviors of each sample at heating rat...Three representative sulfide ore samples were collected from typical metal mines,and their corresponding pre-oxidized products were obtained under nature environment.The thermal behaviors of each sample at heating rates of 5,10,15 and 20 °C/min in air flow from ambient temperature to 800 °C were studied by simultaneous thermal analysis and the TG/DSC curves before and after the pre-oxidation were compared.By the peak temperature of DTG curves,the whole reaction process for each sample was divided into different stages,and the apparent activation energies were calculated by the Ozawa-Flynn-Wall method.The results show that the reaction process of each sample after pre-oxidation is more complex,with quicker reaction rates,fewer heat production quantities,and higher or lower ignition-points.The apparent activation energies decrease from 364.017-474.228 kJ/mol to 244.523- 333.161 kJ/mol.Therefore,sulfide ores are more susceptible to spontaneous combustion after the pre-oxidation.展开更多
Condalia microphylla Cav. （Rhamnaceae）, popularly known as ＂piquillin＂, is widely distributed in Patagonia. The drupes are consumed as fresh fruits by Argentine communities. The aim of this work was to quantify th...Condalia microphylla Cav. （Rhamnaceae）, popularly known as ＂piquillin＂, is widely distributed in Patagonia. The drupes are consumed as fresh fruits by Argentine communities. The aim of this work was to quantify the nutritional value of C. microphylla fruit and the phenolic compounds present and to determine the functional antioxidant properties in vitro and in vivo. The nutritional value was determined according to the Association of Official Analytical Chemists （AOAC） methodology, and phenolic compounds were quantified by diode-array detection （HPLC-DAD）. Antioxidant activity in vitro and in vivo was analyzed through the use of the radical species 2,2-diphenyl-l-picrylhydrazyl （DPPH） and zebrafish model, respectively. Quercetin-3-O-rutinoside （rutin） was the single principal phenolic compound. The extracts contained in vitro antioxidant activities and total phenolic contents （TPCs） between 1,143 ~ 112 lag and 4,633 ~ 174 lag gallic-acid equivalents （GAEs） per 100 g dry weight （DW）, though no relationship was found between the latter parameter and the antioxidant activity of the extracts. When zebrafish larvae were exposed to oxidative stress （2.4% v/v H2O2）, a concentration as low as 1.44 lag of GAEs/mL of piquillin-derived polyphenols inhibited lipid oxidation by up to 40%. Thus, in view of these advantageous functional food properties and the opportunity to exploit this Patagonian natural resource, piquillin consumption should be promoted worldwide.展开更多
The objective of this study was to explain the determinants of the fresh vegetables purchase decision by Chinese urban consumers in Beijing including awareness and attitudes to food safety, and their willingness to p...The objective of this study was to explain the determinants of the fresh vegetables purchase decision by Chinese urban consumers in Beijing including awareness and attitudes to food safety, and their willingness to pay （WTP） more for specific safety characteristics when buying fresh vegetables. The research rationale arises out of a history of food safety scares and scandals in China, and a national government response to promote quality assurance and safety through labelling. The primary hypothesis was that an understanding of food safety systems and product labelling, and trust in supply chain integrity would be key determinants in consumer willingness to purchase and pay more for safety assured vegetables. Based on a questionnaire survey of consumers in Beijing, the analysis found that the major factors underlying the purchase decision of fresh vegetables were product freshness, convenience and competitive price rather than assured product labelling. The decisions whether to purchase assurance-labelled vegetables and WTP more for chemical residue-free product were analysed by binomial and ordinal multinomial logit modelling respectively. It revealed a WTP moreof between 20% and 40%. Monthly household income was a key determinant of both quality assured product and WTP, together with degree of concern over residues, trust in retailer and assurance labels and place of purchase. The results suggest much still remains to be done to build trust though rigorous monitoring and enforcement of food safety standards to improve supply chain integrity and consumer confidence.展开更多
Self-compacting concrete （SCC） is defined so that no vibration is necessary for the compaction. The main criteria of producing SCC have to satisfy the following characteristics [1, 2, 3]： （1） Ability to flow into...Self-compacting concrete （SCC） is defined so that no vibration is necessary for the compaction. The main criteria of producing SCC have to satisfy the following characteristics [1, 2, 3]： （1） Ability to flow into and completely fill complex forms under its own weight; （2） Ability to pass through and bond to congested reinforcements; （3） High resistance to aggregate segregation. Self-compacting concrete presents a significant sign in improving the product quality and efficiency of the building industry. It also enhances the working conditions and the quality and appearance of concrete. Japan has been used self-compacting concrete in bridge, building and tunnel construction since the early 1990s. In the last decade, SCC has been produced a high potential for greater acceptance and wider applications in highway bridge construction in the Europe and U.S.. However, till now, there is no application of SCC in the construction industry in Egypt. Therefore, the main objective of this research is to produce SCC by using the locally available materials in our region such as basalt, gravel, sand, limestone powder and silica fume. Experimental programme was designed to characterize the properties of fresh and hardened SCC. It comprises different concrete mixes thbricated with different types and percentages of constituent materials. Three full-scale reinforced concrete beams were fabricated from the SCC mixes and tested under flexure. For the purpose of comparison, an extra RC beam was made of conventional normal concrete to serve as a reference beam. This study, in general, demonstrated that the applications of SCC in construction industry oiler products with enhanced characteristics as well as could be economical.展开更多
In the work reported here, the potential of different methods （cold and hot water, and ethanolic） of extraction of Indian almond （Terminalia catappa L.）, fresh and fallen leaves as an anti-bacterial agent was inve...In the work reported here, the potential of different methods （cold and hot water, and ethanolic） of extraction of Indian almond （Terminalia catappa L.）, fresh and fallen leaves as an anti-bacterial agent was investigated. The hot water extract did not show any spectrum of activity against the selected bacteria while the cold water extract showed slight antibacterial activity suggesting that the effective components are heat labile. The ethanolic extracts of the leaves have higher antibiotic spectrum of activity than the cold water extract showing ethanol to be a better solvent in extracting the effective component. The fallen leaves seem to have a higher concentration of the effective component against the bacteria while ethanolic extract of the fresh leaves have similar spectrum of activity to Ciprofloxacin and Nitrofuratoin. These suggest that some effective components are lost when leaves fall off while some seem to increase in concentration. Fresh and fallen leaves contain tannin and flavonoids. In addition, the fallen leaves contain flavones. This might be responsible for the higher activity of fallen leaves extract observed against Pseudomonas and Staphylococcus spp. in our study. Combined use of extracts from fresh and fallen leaves broadened the spectrum of activity.展开更多
This paper reviews results of some morphometric properties and chemical analyses of natural populations of the Cornelian cherry collected in the Vojvodina Province in 2008. Purpose of this study was the selection of t...This paper reviews results of some morphometric properties and chemical analyses of natural populations of the Cornelian cherry collected in the Vojvodina Province in 2008. Purpose of this study was the selection of the best genotypes for future breeding program until the final goal and that is standardizing Cornelian cherry cultivars. Chemical content has been found to depend on the genotype. Total sugar content in fruits ranged from 11.77% （CPC16） to 41.62% （BPC7）, vitamin C from 17.15 mg/100 g （APC8） to 42.30 rag/100 g of fresh fruit （APC2）, Ca pectat from 0.17% （APC6） to 2.52% （KC 1 ） and anthocyanin from 22.65 mg/100 g （APC4）to 96.30 rag/100 g of fresh fruit （BPC1）. Cornelian cherry fruits have an especially high content of minerals compared with other fruit species： the potassium content （in ppm） ranges from 2330 （APC6） to 11487 （APC4）, the calcium content from 33.80 （APC6） to 1307.70 （BPC1）, the sodium content from 22.82 （BPC8） to 273.48 （APC8）, the magnesium content from 10.20 （APC6） to 372.80 （APC8） and the iron content from 2.38 （KC2） to 14.40 （APCS）. The balanced content of nutrients, a wide range of food products made from the Cornelian cherry and an extremely high nutritional value make this fruit species a highly recommendable food item, especially if it comes from organic production.展开更多
In the Korean Peninsula the Meso-Cenozoic basins were mainly formed due to fault block and block movement. The Mesozoic fracture structures correspond basically to modem large rivers in direction. Such faults were usu...In the Korean Peninsula the Meso-Cenozoic basins were mainly formed due to fault block and block movement. The Mesozoic fracture structures correspond basically to modem large rivers in direction. Such faults were usually developed to rift and formed lake-type tectonic basin, such as the Amrokgang-, Taedonggang-, Ryesonggang-, Hochongang-, Jangphari-, Susongchon-, Pujon-, and Nampho basins. The Mesozoic strata are considered to be divided into the Lower Jurassic Taedong System, Upper Jurassic Jasong System, Upper Jurassic-early Lower Cretaceous Taebo System, and the Upper Cretaceous-Paleocene （ Chonjaebong, Hongwon, Jaedok Series）. The Cenozoic block movement succeeded the Mesozoic fault block movement. The Kilju-Myongchon Graben and Tumangang Basin, etc, are the basins related to the fault zones developed from the Oligocene to Miocene. In addition, the Tertiary basins were formed in many areas in the Miocene （e. g. Sinhung, Oro, Hamhung, Yonghung, Anbyon, Cholwon, etc）. The Cenozoic sedimentation occurred mainly from the late Oligocene to Miocene. The Kilju-Myongchon Graben was the fore deep connected to the sea and the basins inclined in the Chugaryong Fault Zone are intramountain basins. Therefore, coal-beating beds and clastic rocks in the intramountain basins and rare marine strata and terrigenous clastic rocks are main sedimentary sequences in the Cenozoic.展开更多
基金supported by the National Nature Science Foundation of China(No.20903054).
文摘The surface nature of fresh Mo2N/Al2O3, Mo2C/Al2O3 and/MoP/Al2O3 catalysts, which were synthesized directly in the IR cell to avoid passivation, were characterized by in situ IR spectroscopy with CO as a probe molecule. CO adsorbed on fresh catalysts showed characteristic IR bands at 2045 cm-1 for Mo2N/Al2O3 catalyst, 2054 cm-1 for MozC/Al2O3 catalyst and 2037 cm-1 for MoP/Al2O3 catalyst, respectively. A strong band at 2200 cm-1 for Mo2N/Al2O3 catalyst, which could be ascribed to NCO species formed when CO reacted upon surface active nitrogen atoms, and a weak band at 2196 cm-1 for Mo2C/Al2O3 catalyst, which could be attributed to CCO species, were also detected. CO adsorbed on fresh Mo2N/Al2O3 catalyst, Mo2C/Al2O3 catalyst and MoP/Al2O3 catalyst, showed strong molecular adsorption, just like noble metals. Our experimental results are bolstered by direct IR evidence demonstrating the similarity in surface electronic property between the fresh Mo2N/Al2O3, Mo2C/Al2O3 and MoP/Al2O3 catalysts and noble metals.
基金Project(51304051)supported by the National Natural Science Foundation of ChinaProject(2012J05088)supported by the Natural Science Foundation of Fujian Province,China+1 种基金Project(022409)supported by School Talent Award of Fuzhou University,ChinaProject(2013-XQ-18)supported by Science&Technology Development Foundation of Fuzhou University,China
文摘Three representative sulfide ore samples were collected from typical metal mines,and their corresponding pre-oxidized products were obtained under nature environment.The thermal behaviors of each sample at heating rates of 5,10,15 and 20 °C/min in air flow from ambient temperature to 800 °C were studied by simultaneous thermal analysis and the TG/DSC curves before and after the pre-oxidation were compared.By the peak temperature of DTG curves,the whole reaction process for each sample was divided into different stages,and the apparent activation energies were calculated by the Ozawa-Flynn-Wall method.The results show that the reaction process of each sample after pre-oxidation is more complex,with quicker reaction rates,fewer heat production quantities,and higher or lower ignition-points.The apparent activation energies decrease from 364.017-474.228 kJ/mol to 244.523- 333.161 kJ/mol.Therefore,sulfide ores are more susceptible to spontaneous combustion after the pre-oxidation.
文摘Condalia microphylla Cav. （Rhamnaceae）, popularly known as ＂piquillin＂, is widely distributed in Patagonia. The drupes are consumed as fresh fruits by Argentine communities. The aim of this work was to quantify the nutritional value of C. microphylla fruit and the phenolic compounds present and to determine the functional antioxidant properties in vitro and in vivo. The nutritional value was determined according to the Association of Official Analytical Chemists （AOAC） methodology, and phenolic compounds were quantified by diode-array detection （HPLC-DAD）. Antioxidant activity in vitro and in vivo was analyzed through the use of the radical species 2,2-diphenyl-l-picrylhydrazyl （DPPH） and zebrafish model, respectively. Quercetin-3-O-rutinoside （rutin） was the single principal phenolic compound. The extracts contained in vitro antioxidant activities and total phenolic contents （TPCs） between 1,143 ~ 112 lag and 4,633 ~ 174 lag gallic-acid equivalents （GAEs） per 100 g dry weight （DW）, though no relationship was found between the latter parameter and the antioxidant activity of the extracts. When zebrafish larvae were exposed to oxidative stress （2.4% v/v H2O2）, a concentration as low as 1.44 lag of GAEs/mL of piquillin-derived polyphenols inhibited lipid oxidation by up to 40%. Thus, in view of these advantageous functional food properties and the opportunity to exploit this Patagonian natural resource, piquillin consumption should be promoted worldwide.
文摘The objective of this study was to explain the determinants of the fresh vegetables purchase decision by Chinese urban consumers in Beijing including awareness and attitudes to food safety, and their willingness to pay （WTP） more for specific safety characteristics when buying fresh vegetables. The research rationale arises out of a history of food safety scares and scandals in China, and a national government response to promote quality assurance and safety through labelling. The primary hypothesis was that an understanding of food safety systems and product labelling, and trust in supply chain integrity would be key determinants in consumer willingness to purchase and pay more for safety assured vegetables. Based on a questionnaire survey of consumers in Beijing, the analysis found that the major factors underlying the purchase decision of fresh vegetables were product freshness, convenience and competitive price rather than assured product labelling. The decisions whether to purchase assurance-labelled vegetables and WTP more for chemical residue-free product were analysed by binomial and ordinal multinomial logit modelling respectively. It revealed a WTP moreof between 20% and 40%. Monthly household income was a key determinant of both quality assured product and WTP, together with degree of concern over residues, trust in retailer and assurance labels and place of purchase. The results suggest much still remains to be done to build trust though rigorous monitoring and enforcement of food safety standards to improve supply chain integrity and consumer confidence.
文摘Self-compacting concrete （SCC） is defined so that no vibration is necessary for the compaction. The main criteria of producing SCC have to satisfy the following characteristics [1, 2, 3]： （1） Ability to flow into and completely fill complex forms under its own weight; （2） Ability to pass through and bond to congested reinforcements; （3） High resistance to aggregate segregation. Self-compacting concrete presents a significant sign in improving the product quality and efficiency of the building industry. It also enhances the working conditions and the quality and appearance of concrete. Japan has been used self-compacting concrete in bridge, building and tunnel construction since the early 1990s. In the last decade, SCC has been produced a high potential for greater acceptance and wider applications in highway bridge construction in the Europe and U.S.. However, till now, there is no application of SCC in the construction industry in Egypt. Therefore, the main objective of this research is to produce SCC by using the locally available materials in our region such as basalt, gravel, sand, limestone powder and silica fume. Experimental programme was designed to characterize the properties of fresh and hardened SCC. It comprises different concrete mixes thbricated with different types and percentages of constituent materials. Three full-scale reinforced concrete beams were fabricated from the SCC mixes and tested under flexure. For the purpose of comparison, an extra RC beam was made of conventional normal concrete to serve as a reference beam. This study, in general, demonstrated that the applications of SCC in construction industry oiler products with enhanced characteristics as well as could be economical.
文摘In the work reported here, the potential of different methods （cold and hot water, and ethanolic） of extraction of Indian almond （Terminalia catappa L.）, fresh and fallen leaves as an anti-bacterial agent was investigated. The hot water extract did not show any spectrum of activity against the selected bacteria while the cold water extract showed slight antibacterial activity suggesting that the effective components are heat labile. The ethanolic extracts of the leaves have higher antibiotic spectrum of activity than the cold water extract showing ethanol to be a better solvent in extracting the effective component. The fallen leaves seem to have a higher concentration of the effective component against the bacteria while ethanolic extract of the fresh leaves have similar spectrum of activity to Ciprofloxacin and Nitrofuratoin. These suggest that some effective components are lost when leaves fall off while some seem to increase in concentration. Fresh and fallen leaves contain tannin and flavonoids. In addition, the fallen leaves contain flavones. This might be responsible for the higher activity of fallen leaves extract observed against Pseudomonas and Staphylococcus spp. in our study. Combined use of extracts from fresh and fallen leaves broadened the spectrum of activity.
文摘This paper reviews results of some morphometric properties and chemical analyses of natural populations of the Cornelian cherry collected in the Vojvodina Province in 2008. Purpose of this study was the selection of the best genotypes for future breeding program until the final goal and that is standardizing Cornelian cherry cultivars. Chemical content has been found to depend on the genotype. Total sugar content in fruits ranged from 11.77% （CPC16） to 41.62% （BPC7）, vitamin C from 17.15 mg/100 g （APC8） to 42.30 rag/100 g of fresh fruit （APC2）, Ca pectat from 0.17% （APC6） to 2.52% （KC 1 ） and anthocyanin from 22.65 mg/100 g （APC4）to 96.30 rag/100 g of fresh fruit （BPC1）. Cornelian cherry fruits have an especially high content of minerals compared with other fruit species： the potassium content （in ppm） ranges from 2330 （APC6） to 11487 （APC4）, the calcium content from 33.80 （APC6） to 1307.70 （BPC1）, the sodium content from 22.82 （BPC8） to 273.48 （APC8）, the magnesium content from 10.20 （APC6） to 372.80 （APC8） and the iron content from 2.38 （KC2） to 14.40 （APCS）. The balanced content of nutrients, a wide range of food products made from the Cornelian cherry and an extremely high nutritional value make this fruit species a highly recommendable food item, especially if it comes from organic production.
文摘In the Korean Peninsula the Meso-Cenozoic basins were mainly formed due to fault block and block movement. The Mesozoic fracture structures correspond basically to modem large rivers in direction. Such faults were usually developed to rift and formed lake-type tectonic basin, such as the Amrokgang-, Taedonggang-, Ryesonggang-, Hochongang-, Jangphari-, Susongchon-, Pujon-, and Nampho basins. The Mesozoic strata are considered to be divided into the Lower Jurassic Taedong System, Upper Jurassic Jasong System, Upper Jurassic-early Lower Cretaceous Taebo System, and the Upper Cretaceous-Paleocene （ Chonjaebong, Hongwon, Jaedok Series）. The Cenozoic block movement succeeded the Mesozoic fault block movement. The Kilju-Myongchon Graben and Tumangang Basin, etc, are the basins related to the fault zones developed from the Oligocene to Miocene. In addition, the Tertiary basins were formed in many areas in the Miocene （e. g. Sinhung, Oro, Hamhung, Yonghung, Anbyon, Cholwon, etc）. The Cenozoic sedimentation occurred mainly from the late Oligocene to Miocene. The Kilju-Myongchon Graben was the fore deep connected to the sea and the basins inclined in the Chugaryong Fault Zone are intramountain basins. Therefore, coal-beating beds and clastic rocks in the intramountain basins and rare marine strata and terrigenous clastic rocks are main sedimentary sequences in the Cenozoic.
