Experiments were carried out to study the transformation of mercury in soils. Results showed that Hg 2+ was immediately converted into other forms once it entered into soils. Bentonite, humus or CaCO 3 accelera...Experiments were carried out to study the transformation of mercury in soils. Results showed that Hg 2+ was immediately converted into other forms once it entered into soils. Bentonite, humus or CaCO 3 accelerated the transformation of Hg 2+ by various mechanisms. Bentonite could convert Hg 2+ into residual form eventually, and application of CaCO 3 enhanced the formation of inorganic Hg. Humus competed strongly with clay minerals for binding Hg 2+ , thus increase of soil humus content led to increased formation of organically bound Hg.展开更多
Chicken manure was composted for 110 d to evaluate changes in organic carbon (C) and humic substance-complexed copper (HS-Cu) extracted with water,sodium hydroxide (NaOH),and sodium pyrophosphate and sodium hydroxide ...Chicken manure was composted for 110 d to evaluate changes in organic carbon (C) and humic substance-complexed copper (HS-Cu) extracted with water,sodium hydroxide (NaOH),and sodium pyrophosphate and sodium hydroxide mixture (Na 4 P 2 O 7-NaOH).The average HS-Cu content from the Na 4 P 2 O 7-NaOH extraction accounted for 46.8% of the total Cu in the compost,followed by those from the NaOH and water extractions,which accounted for 34.5% and 6% of the total Cu in the compost,respectively.NaOH-Na 4 P 2 O 7-extractable HS-Cu increased throughout the composting process.NaOH-extractable HS-Cu increased during the first 50 d of composting and then leveled off.Water-extractable HS-Cu enhanced during the first 21 d and then decreased.Water-extractable HS-Cu was not correlated to NaOH-or NaOH-Na 4 P 2 O 7-extractable organic C.The average amount of Cu leached from the compost was about 20% of the total Cu in the chicken manure and Cu leaching increased during the first 35 d of composting and then decreased.Leaching of Cu was significantly correlated to the concentrations of HS-Cu extracted with NaOH and water,but was not correlated to the concentration of HS-Cu extracted with NaOH-Na 4 P 2 O 7.Thus,NaOH-and water-extractable HS-Cu were relatively labile and NaOH-Na 4 P 2 O 7-extractable HS-Cu was relatively immobile.Composting process after rapid decomposition could result in low potential of Cu leaching because of formation of more NaOH-Na 4 P 2 O 7-extractable HS-Cu.展开更多
The present work summarizes recent investigations carried out about the usage of natural antioxidants in lipid-rich food during processing. Synthetic antioxidants have been used as food additives to retard lipid oxida...The present work summarizes recent investigations carried out about the usage of natural antioxidants in lipid-rich food during processing. Synthetic antioxidants have been used as food additives to retard lipid oxidation and development of off-flavor for over 50 years. However, the literature has expressed safety concerns and health risks （toxic and carcinogenic effects） associated with the use of synthetic antioxidants recently. Natural antioxidative substances from the polyphenols of edible plants are believed to be safer and may provide with additional health benefits and more effective compared to synthetic antioxidants. Due to the fact that natural antioxidants are additives that people mixed with food and consumed for centuries, they are known to be safe by the consumer. Therefore, it is an area worth to investigate due to consumer concerns about health. In the literature, there are many studies showing that the natural antioxidants have important antioxidant effect. Plants （oil seeds, cereals, vegetables, fruits, herb and spices）, compounds from animal source （peptides and amino acids）, enzymes and some microorganisms are important natural antioxidants. Plant extracts have been widely used to retard lipid oxidation in foods during frying and accelerated storage processes. They were found as strong antioxidant sources due to their high contents of phenolic compounds. There are countless studies about natural antioxidants. However, they have not been investigated completely by means of toxicology.展开更多
Highly porous Ti-Co alloy specimens for biomedical applications were synthesized by powder metallurgy based space holder technique. Ti alloys have high melting temperature and affinity for oxygen, which makes Ti alloy...Highly porous Ti-Co alloy specimens for biomedical applications were synthesized by powder metallurgy based space holder technique. Ti alloys have high melting temperature and affinity for oxygen, which makes Ti alloys difficult to be processed. The Co addition reduces the melting temperature and Ti-Co alloy was sintered at lower temperatures. The electrochemical corrosion behaviour of the specimens was examined in the artificial saliva solution. The effects of Co content of the alloy, the p H value and fluoride concentration of the artificial saliva solution on the electrochemical corrosion properties of the specimens were investigated. The microstructure and mechanical properties of the specimens were examined. The electrochemical impedance spectroscopy results indicate that the corrosion resistance of the specimens decreases at high fluoride concentrations and low p H value. The defect density increases with increasing the fluoride concentration and decreasing the p H value of artificial saliva according to Mott-Schottky analysis.展开更多
The formation constants of Co￣(2+), Ni￣(2+), Cu￣(2+) and Zn￣(2+) complexes with humic acid (HA) and fulvicacid (FA) in red soil were determined by the potentiometric titration method. The constants as a functionof...The formation constants of Co￣(2+), Ni￣(2+), Cu￣(2+) and Zn￣(2+) complexes with humic acid (HA) and fulvicacid (FA) in red soil were determined by the potentiometric titration method. The constants as a functionof composition of the complexation solutions were obtained by two graphical approaches respectively Theformation constants decreased with increasing concentration of metal in the solution. The results provideunambiguous evidence for the heterogeneity of the function groups of humic substances. The formationconstants of FA were much smaller than those of HA, and the formation constants of Cu￣(2+) were muchgreater than those of Co￣(2+) , Ni￣(2+) and Zn￣(2+) . The potentiometric titration method for determining formationconstants are also discussed in the article.展开更多
This study was carried out at the vegetable research field, College of Agriculture, University of Duhok, during the growing season of 2009 using the eggplant local cultivar. And a factorial Randomized complete block d...This study was carried out at the vegetable research field, College of Agriculture, University of Duhok, during the growing season of 2009 using the eggplant local cultivar. And a factorial Randomized complete block design （F-RCBD）. The experiment consisted of two factors, the first was inoculations with and without humic acid, and the second factor was three levels of dry bread yeast （0.5, 10 gm/L）. The results revealed that the growth was significantly increased in term of plant height, branches number%, total chlorophyll and mineral content in leaves （N.P.K） and the yield in term of fruit number/plant, fruit weight （gm）, plant yield （gm/plant）, total yield （ton/hectare）, fruit length and fruit diameter. The interaction between humic acid and bread yeast was highly improved the growth and yield traits.展开更多
A pot experiment was conducted in lath house to study the response of six month-old seedlings of sour orange （Citrus aurantium L.） irrigated with salinity water （1, 2 or 4 ds/m） for four month. The seedling was sp...A pot experiment was conducted in lath house to study the response of six month-old seedlings of sour orange （Citrus aurantium L.） irrigated with salinity water （1, 2 or 4 ds/m） for four month. The seedling was sprayed with putrescine at 0, 150 or 300 mg/L concentrations for three times with month interval, for investigation the effects of putrrescine spraying on hormonal changes in sour orange seedlings under salt stress. One month after the last putrescine application, the leaves of the vegetative shoots were picked for endogenous plant hormone determination. The results indicate that increasing level of irrigation water salinity to 4 ds/m significantly increased ABA, Put and SA; whereas, decreasing IAA and GA in leave. Spraying vegetative canopy with putreseine at 300 mg/L increased 1AA, SA, ABA and Put, while decreased GA. It can be concluded that the adverse effects of high salinity irrigated water on endogenous plant hormone can be ameliorated, to some extent, by exogenous application of Put at 150 mg/L or 300 mg/L concentration.展开更多
文摘Experiments were carried out to study the transformation of mercury in soils. Results showed that Hg 2+ was immediately converted into other forms once it entered into soils. Bentonite, humus or CaCO 3 accelerated the transformation of Hg 2+ by various mechanisms. Bentonite could convert Hg 2+ into residual form eventually, and application of CaCO 3 enhanced the formation of inorganic Hg. Humus competed strongly with clay minerals for binding Hg 2+ , thus increase of soil humus content led to increased formation of organically bound Hg.
基金Project supported by the Ministry of Science and Technology of China (No. 2007BAD89B16)the National Natural Science Foundation of China (No. 39800093)+1 种基金the National Undergraduate Innovational Experimentation Program of Chinathe Youth Planning Program of Northwest A & F University,China
文摘Chicken manure was composted for 110 d to evaluate changes in organic carbon (C) and humic substance-complexed copper (HS-Cu) extracted with water,sodium hydroxide (NaOH),and sodium pyrophosphate and sodium hydroxide mixture (Na 4 P 2 O 7-NaOH).The average HS-Cu content from the Na 4 P 2 O 7-NaOH extraction accounted for 46.8% of the total Cu in the compost,followed by those from the NaOH and water extractions,which accounted for 34.5% and 6% of the total Cu in the compost,respectively.NaOH-Na 4 P 2 O 7-extractable HS-Cu increased throughout the composting process.NaOH-extractable HS-Cu increased during the first 50 d of composting and then leveled off.Water-extractable HS-Cu enhanced during the first 21 d and then decreased.Water-extractable HS-Cu was not correlated to NaOH-or NaOH-Na 4 P 2 O 7-extractable organic C.The average amount of Cu leached from the compost was about 20% of the total Cu in the chicken manure and Cu leaching increased during the first 35 d of composting and then decreased.Leaching of Cu was significantly correlated to the concentrations of HS-Cu extracted with NaOH and water,but was not correlated to the concentration of HS-Cu extracted with NaOH-Na 4 P 2 O 7.Thus,NaOH-and water-extractable HS-Cu were relatively labile and NaOH-Na 4 P 2 O 7-extractable HS-Cu was relatively immobile.Composting process after rapid decomposition could result in low potential of Cu leaching because of formation of more NaOH-Na 4 P 2 O 7-extractable HS-Cu.
文摘The present work summarizes recent investigations carried out about the usage of natural antioxidants in lipid-rich food during processing. Synthetic antioxidants have been used as food additives to retard lipid oxidation and development of off-flavor for over 50 years. However, the literature has expressed safety concerns and health risks （toxic and carcinogenic effects） associated with the use of synthetic antioxidants recently. Natural antioxidative substances from the polyphenols of edible plants are believed to be safer and may provide with additional health benefits and more effective compared to synthetic antioxidants. Due to the fact that natural antioxidants are additives that people mixed with food and consumed for centuries, they are known to be safe by the consumer. Therefore, it is an area worth to investigate due to consumer concerns about health. In the literature, there are many studies showing that the natural antioxidants have important antioxidant effect. Plants （oil seeds, cereals, vegetables, fruits, herb and spices）, compounds from animal source （peptides and amino acids）, enzymes and some microorganisms are important natural antioxidants. Plant extracts have been widely used to retard lipid oxidation in foods during frying and accelerated storage processes. They were found as strong antioxidant sources due to their high contents of phenolic compounds. There are countless studies about natural antioxidants. However, they have not been investigated completely by means of toxicology.
基金supported partially by Scientific Research Projects Coordination Unit of Istanbul University, Project numbers 42796 and 42922
文摘Highly porous Ti-Co alloy specimens for biomedical applications were synthesized by powder metallurgy based space holder technique. Ti alloys have high melting temperature and affinity for oxygen, which makes Ti alloys difficult to be processed. The Co addition reduces the melting temperature and Ti-Co alloy was sintered at lower temperatures. The electrochemical corrosion behaviour of the specimens was examined in the artificial saliva solution. The effects of Co content of the alloy, the p H value and fluoride concentration of the artificial saliva solution on the electrochemical corrosion properties of the specimens were investigated. The microstructure and mechanical properties of the specimens were examined. The electrochemical impedance spectroscopy results indicate that the corrosion resistance of the specimens decreases at high fluoride concentrations and low p H value. The defect density increases with increasing the fluoride concentration and decreasing the p H value of artificial saliva according to Mott-Schottky analysis.
文摘The formation constants of Co￣(2+), Ni￣(2+), Cu￣(2+) and Zn￣(2+) complexes with humic acid (HA) and fulvicacid (FA) in red soil were determined by the potentiometric titration method. The constants as a functionof composition of the complexation solutions were obtained by two graphical approaches respectively Theformation constants decreased with increasing concentration of metal in the solution. The results provideunambiguous evidence for the heterogeneity of the function groups of humic substances. The formationconstants of FA were much smaller than those of HA, and the formation constants of Cu￣(2+) were muchgreater than those of Co￣(2+) , Ni￣(2+) and Zn￣(2+) . The potentiometric titration method for determining formationconstants are also discussed in the article.
文摘This study was carried out at the vegetable research field, College of Agriculture, University of Duhok, during the growing season of 2009 using the eggplant local cultivar. And a factorial Randomized complete block design （F-RCBD）. The experiment consisted of two factors, the first was inoculations with and without humic acid, and the second factor was three levels of dry bread yeast （0.5, 10 gm/L）. The results revealed that the growth was significantly increased in term of plant height, branches number%, total chlorophyll and mineral content in leaves （N.P.K） and the yield in term of fruit number/plant, fruit weight （gm）, plant yield （gm/plant）, total yield （ton/hectare）, fruit length and fruit diameter. The interaction between humic acid and bread yeast was highly improved the growth and yield traits.
文摘A pot experiment was conducted in lath house to study the response of six month-old seedlings of sour orange （Citrus aurantium L.） irrigated with salinity water （1, 2 or 4 ds/m） for four month. The seedling was sprayed with putrescine at 0, 150 or 300 mg/L concentrations for three times with month interval, for investigation the effects of putrrescine spraying on hormonal changes in sour orange seedlings under salt stress. One month after the last putrescine application, the leaves of the vegetative shoots were picked for endogenous plant hormone determination. The results indicate that increasing level of irrigation water salinity to 4 ds/m significantly increased ABA, Put and SA; whereas, decreasing IAA and GA in leave. Spraying vegetative canopy with putreseine at 300 mg/L increased 1AA, SA, ABA and Put, while decreased GA. It can be concluded that the adverse effects of high salinity irrigated water on endogenous plant hormone can be ameliorated, to some extent, by exogenous application of Put at 150 mg/L or 300 mg/L concentration.
