Dextran in sugarcane production process is formed by Leuconostoc rnesenteroides. The content levels of dextran is related to sugarcane varieties, field condition (planting pattern, temperature, humidity, sunlight, so...Dextran in sugarcane production process is formed by Leuconostoc rnesenteroides. The content levels of dextran is related to sugarcane varieties, field condition (planting pattern, temperature, humidity, sunlight, soil, foreign material), de- gree of injury (refractory cane, harvesting methods), and can be rapidly and accu- rately measured by Dextran Immunonephelometric Test Kit. The presence of dextran indicates that sucrose has been lost, so sugarcane dextran is a direct and reliable indicator to measure sugarcane freshness and quality.展开更多
The changes in the contents of adenosine 5’-triphosphate (ATP) and its related breakdown compounds were investigated in the adductor muscle, mantle, gill and body trunk of oyster (Crassostrea gigas) during frozen sto...The changes in the contents of adenosine 5’-triphosphate (ATP) and its related breakdown compounds were investigated in the adductor muscle, mantle, gill and body trunk of oyster (Crassostrea gigas) during frozen storage at -20℃ and -30℃ and compared with that of the fresh oyster. The investigation was performed using an HPLC system. Different extents of ATP decomposi- tion were found in various tissues frozen at the two temperatures. The K, K’ and A.E.C values were calculated as the chemical fresh- ness indices. Considering the results of sensory evaluation, the A.E.C. value in body trunk at -20℃ and -30℃ could be used as the best freshness index for frozen oyster.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
The objective of the present study was to determine the proper sources and concentrations of soybean lecithin (phosphatidylcholine, PC) to be used as substitute for hen egg yolk in extender for preserving goat semen...The objective of the present study was to determine the proper sources and concentrations of soybean lecithin (phosphatidylcholine, PC) to be used as substitute for hen egg yolk in extender for preserving goat semen. Two sources of soybean lecithin (20% and 95% soybean phosphatidylcholine; PC20 and PC95) and three concentrations (1%, 2% and 3% v/v) of PC20 and PC95 supplemented in Tris-citric acid-fructose (TCF) extender were tested. The TCF extender supplemented with 20% hen egg yolk was used as a control. Fresh semen samples were collected from 3 goats by artificial vagina. Seminal plasma was removed by centrifugation and sperm pellets were pooled together and divided into 7 groups according to types of extender. The diluted semen samples were kept at 4 ℃ (equilibration). The semen qualities including progressive motility, sperm viability, sperm plasma membrane integrity and tail abnormalities were evaluated before dilution and after 4 hrs equilibration. It was found that the progressive motility of equilibrated semen in egg yolk and PC20 extenders were higher than those in PC95 extender (P 〈 0.05). Sperm viability was lower in 1% and 2% PC95 extender compared to other extenders (P 〈 0.05). PC20 extender maintained the sperm membrane integrity and normal tail morphology at low temperature better than egg yolk and PC95 (P 〈 0.05). It can be concluded that 20% soybean phosphatidylcholine supplemented in TCF extender at 1%-3% (v/v) is as effective as hen egg yolk to preserve goat semen during equilibration at 4 ℃ for 4 hrs .展开更多
The Litter nutrient concentrations of N, P, Ca, Mg, K and Na in mature leaves, twigs and reproductive parts and their relationship between senescent and young leaves were investigated in five forest species: Acacia n...The Litter nutrient concentrations of N, P, Ca, Mg, K and Na in mature leaves, twigs and reproductive parts and their relationship between senescent and young leaves were investigated in five forest species: Acacia nilotica, Acacia leucophloea. Tectona grandis, Miliusa tomentosa and Butea monosperma in Indian tropical dry deciduous forest in Western India.. Total dry matter of plant species was recorded and analyzed for N, P, Ca, Mg, K and Na. A. nilotica had the highest concentrations of N in leaf, while ,4. leucophloea had the highest concentrations of Ca and Mg in leaf. The highest concentrations of P in leaf were found in A. nilotica, A. leucophloea and B. monosperma where as lowest in T. grandis and M. tomentosa. No significant differences in K and Na were registered among the species. A marked seasonal variability was ob- served in the concentrations of N, P and K, except for Ca and Mg. Potas- sium is the single element that undergoes leaching and mobilization in all species. Resorped N and P can be used for the production of fresh leaf in the following annual cycle. Nutrient resorption and retranslocation from senescent leaves and litter supports the production of new foliage and increase the fertility of soil.展开更多
Major royal jelly protein 1(MRJP1), designated apalbumin 1, has been regarded as a freshness marker of royal jelly(RJ). A MRJP1-specific peptide(IKEALPHVPIFD) identified by bioinformatics analysis of homologous ...Major royal jelly protein 1(MRJP1), designated apalbumin 1, has been regarded as a freshness marker of royal jelly(RJ). A MRJP1-specific peptide(IKEALPHVPIFD) identified by bioinformatics analysis of homologous members of the major royal protein family was synthesized and used to raise polyclonal anti-MRJP1 antibody(antiSP-MRJP1 antibody). Western blot analysis showed that anti-SP-MRJP1 antibody only reacted with MRJP1 in RJ. In contrast, the previously reported antibody against recombinant MRJP1(anti-R-MRJP1 antibody) reacted with other members of MRJP family in RJ. Enzyme-linked immunosorbent assay(ELISA) using anti-SP-MRJP1 antibody demonstrated that MRJP1 content in RJ stored at 40 °C significantly degraded by 37.3%, 55.9%, 58.0%, 60.6%, 65.7%, 72.7%, and 73.1% at 7, 14, 21, 28, 35, 42, and 49 d, respectively, when compared with MRJP1 content in fresh RJ(0 d). Optical density analysis of MRJP bands from sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) profiles demonstrated that the degradation of MRJP1, MRJP2, MRJP3, and MRJP5 in RJ was strongly and positively correlated with the period of storage(P〈0.0001). Our results indicated anti-SP-MRJP1 antibody was highly specific for MRJP1, and ELISA using the antibody is a sensitive and easy-to-use method to determine the freshness and authenticity of RJ.展开更多
Intrinsic viscosity is one of the most fundamental properties of dilute polymer solutions; its study forms an integral part of the cornerstone of the modern macromolecular theory. However, a general theory applicable ...Intrinsic viscosity is one of the most fundamental properties of dilute polymer solutions; its study forms an integral part of the cornerstone of the modern macromolecular theory. However, a general theory applicable to any chain architectures and solvent conditions has remained elusive, due to the formidable challenges in the theoretical treatment of the long-range, many-body and accumulative hydrodynamic effects. Recently, Lijia An and coworkers at the Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, has developed a new approach that largely overcomes these challenges. Their new theory provides a simple and unified theoretical framework for describing the intrinsic viscosity of polymers with arbitrary architectures under any solvent conditions and forms the theoretical basis for inferring the polymer chain structure from intrinsic viscosity measurements. Comparisons with existing experimental data yield extensive, quantitative agreement.展开更多
基金Supported by Special Fund for Construction Project of Bagui ScholarsSpecial Fund for Modern Agricultural Industry Technology System Construction(CARS-20-4-5)
文摘Dextran in sugarcane production process is formed by Leuconostoc rnesenteroides. The content levels of dextran is related to sugarcane varieties, field condition (planting pattern, temperature, humidity, sunlight, soil, foreign material), de- gree of injury (refractory cane, harvesting methods), and can be rapidly and accu- rately measured by Dextran Immunonephelometric Test Kit. The presence of dextran indicates that sucrose has been lost, so sugarcane dextran is a direct and reliable indicator to measure sugarcane freshness and quality.
文摘The changes in the contents of adenosine 5’-triphosphate (ATP) and its related breakdown compounds were investigated in the adductor muscle, mantle, gill and body trunk of oyster (Crassostrea gigas) during frozen storage at -20℃ and -30℃ and compared with that of the fresh oyster. The investigation was performed using an HPLC system. Different extents of ATP decomposi- tion were found in various tissues frozen at the two temperatures. The K, K’ and A.E.C values were calculated as the chemical fresh- ness indices. Considering the results of sensory evaluation, the A.E.C. value in body trunk at -20℃ and -30℃ could be used as the best freshness index for frozen oyster.
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The objective of the present study was to determine the proper sources and concentrations of soybean lecithin (phosphatidylcholine, PC) to be used as substitute for hen egg yolk in extender for preserving goat semen. Two sources of soybean lecithin (20% and 95% soybean phosphatidylcholine; PC20 and PC95) and three concentrations (1%, 2% and 3% v/v) of PC20 and PC95 supplemented in Tris-citric acid-fructose (TCF) extender were tested. The TCF extender supplemented with 20% hen egg yolk was used as a control. Fresh semen samples were collected from 3 goats by artificial vagina. Seminal plasma was removed by centrifugation and sperm pellets were pooled together and divided into 7 groups according to types of extender. The diluted semen samples were kept at 4 ℃ (equilibration). The semen qualities including progressive motility, sperm viability, sperm plasma membrane integrity and tail abnormalities were evaluated before dilution and after 4 hrs equilibration. It was found that the progressive motility of equilibrated semen in egg yolk and PC20 extenders were higher than those in PC95 extender (P 〈 0.05). Sperm viability was lower in 1% and 2% PC95 extender compared to other extenders (P 〈 0.05). PC20 extender maintained the sperm membrane integrity and normal tail morphology at low temperature better than egg yolk and PC95 (P 〈 0.05). It can be concluded that 20% soybean phosphatidylcholine supplemented in TCF extender at 1%-3% (v/v) is as effective as hen egg yolk to preserve goat semen during equilibration at 4 ℃ for 4 hrs .
基金Foundationfor Ecological Security,Anand,Gujarat for financial assistance of this research project
文摘The Litter nutrient concentrations of N, P, Ca, Mg, K and Na in mature leaves, twigs and reproductive parts and their relationship between senescent and young leaves were investigated in five forest species: Acacia nilotica, Acacia leucophloea. Tectona grandis, Miliusa tomentosa and Butea monosperma in Indian tropical dry deciduous forest in Western India.. Total dry matter of plant species was recorded and analyzed for N, P, Ca, Mg, K and Na. A. nilotica had the highest concentrations of N in leaf, while ,4. leucophloea had the highest concentrations of Ca and Mg in leaf. The highest concentrations of P in leaf were found in A. nilotica, A. leucophloea and B. monosperma where as lowest in T. grandis and M. tomentosa. No significant differences in K and Na were registered among the species. A marked seasonal variability was ob- served in the concentrations of N, P and K, except for Ca and Mg. Potas- sium is the single element that undergoes leaching and mobilization in all species. Resorped N and P can be used for the production of fresh leaf in the following annual cycle. Nutrient resorption and retranslocation from senescent leaves and litter supports the production of new foliage and increase the fertility of soil.
基金supported by the Public Beneficial Scientific&Technical Plan of Zhejiang(No.2011C22039)the Important Scientific & Technical Plan of Zhejiang(No.2011C12023)+2 种基金the Important Scientific & Technical Innovation Project of Hangzhou(No.20131812A25)the Foundation of Fuli Institute of Food Science of Zhejiang University(No.KY201404)the National Natural Science Foundation of China(No.31271848)
文摘Major royal jelly protein 1(MRJP1), designated apalbumin 1, has been regarded as a freshness marker of royal jelly(RJ). A MRJP1-specific peptide(IKEALPHVPIFD) identified by bioinformatics analysis of homologous members of the major royal protein family was synthesized and used to raise polyclonal anti-MRJP1 antibody(antiSP-MRJP1 antibody). Western blot analysis showed that anti-SP-MRJP1 antibody only reacted with MRJP1 in RJ. In contrast, the previously reported antibody against recombinant MRJP1(anti-R-MRJP1 antibody) reacted with other members of MRJP family in RJ. Enzyme-linked immunosorbent assay(ELISA) using anti-SP-MRJP1 antibody demonstrated that MRJP1 content in RJ stored at 40 °C significantly degraded by 37.3%, 55.9%, 58.0%, 60.6%, 65.7%, 72.7%, and 73.1% at 7, 14, 21, 28, 35, 42, and 49 d, respectively, when compared with MRJP1 content in fresh RJ(0 d). Optical density analysis of MRJP bands from sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) profiles demonstrated that the degradation of MRJP1, MRJP2, MRJP3, and MRJP5 in RJ was strongly and positively correlated with the period of storage(P〈0.0001). Our results indicated anti-SP-MRJP1 antibody was highly specific for MRJP1, and ELISA using the antibody is a sensitive and easy-to-use method to determine the freshness and authenticity of RJ.
文摘Intrinsic viscosity is one of the most fundamental properties of dilute polymer solutions; its study forms an integral part of the cornerstone of the modern macromolecular theory. However, a general theory applicable to any chain architectures and solvent conditions has remained elusive, due to the formidable challenges in the theoretical treatment of the long-range, many-body and accumulative hydrodynamic effects. Recently, Lijia An and coworkers at the Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, has developed a new approach that largely overcomes these challenges. Their new theory provides a simple and unified theoretical framework for describing the intrinsic viscosity of polymers with arbitrary architectures under any solvent conditions and forms the theoretical basis for inferring the polymer chain structure from intrinsic viscosity measurements. Comparisons with existing experimental data yield extensive, quantitative agreement.