[Objective]The aim was to isolate and identify the pathogen causing black spot disease in guava（Psidium guajava）,so as to determine its taxonomic status.[Method]The fungus was identified by determining its pathogeni...[Objective]The aim was to isolate and identify the pathogen causing black spot disease in guava（Psidium guajava）,so as to determine its taxonomic status.[Method]The fungus was identified by determining its pathogenicity,observing its morphology characteristics and analyzing its ITS sequence.[Result]The pathogen causing black spot disease in guava was a strain of Guignardia mangiferae.[Conclusion]This study will provide theoretical basis for curing black spot disease of guava.展开更多
In this study, Ficus carica L. ‘Masui Dauphine＇ was used as the experi- mental material to investigate the effects of explant type, basal medium, hormone types and concentrations on in vitro rapid propagation of‘Ma...In this study, Ficus carica L. ‘Masui Dauphine＇ was used as the experi- mental material to investigate the effects of explant type, basal medium, hormone types and concentrations on in vitro rapid propagation of‘Masui Dauphine＇. Accord- ing to the results, the most suitable explants for in vitro rapid propagation of ‘Masui Dauphine＇ were axillary buds and the best medium was modified MS ＋ 1.0 mg/L 6-BA ＋ 0. 05 mg/L NAA ＋ 1.0 mg/L GA3 ＋ 20 mg/L sucrose ＋ 7 mg/L agar, pH 5.8. This study provided scientific basis for barge-scale cultivation of‘Masui Dauphine ＇.展开更多
The ultrastructure and intercellular connection of the sugar unloading zone (i.e. the phloem in the dorsal vascular bundle and the phloem_surrounding the assimilate sink_cells) of grape ( Vitis vinifera× V. labr...The ultrastructure and intercellular connection of the sugar unloading zone (i.e. the phloem in the dorsal vascular bundle and the phloem_surrounding the assimilate sink_cells) of grape ( Vitis vinifera× V. labrusca cv. Jingchao) berry was observed via transmission electron microscopy. The results showed that during the early developmental stages of grape berry, numerous plasmodesmata were found in the phloem between sieve element (SE) and companion cell (CC), between SE/CC complexes, between SE/CC complex and phloem parenchyma cell and in between phloem parenchyma cells, which made the phloem a symplastic integration, facilitating sugar unloading from sieve elements into both companion cells and phloem parenchyma cells via a symplastic pathway. On the contrary, there was almost no plasmodesma between phloem and its surrounding flesh photoassimilate sink_cells, neither in between the flesh photoassimilate sink_cells giving rise to a symplastic isolation both between phloem and its surrounding flesh photoassimilate sink_cells, as well as among the flesh photoassimilate sink_cells. This indicated that both the sugar unloading from phloem and postphloem transport of sugars should be mainly via an apoplastic pathway. During the ripening stage, most of the plasmodesmata between SE/CC complex and the surrounding phloem parenchyma cells were shown to be blocked by the electron_opaque globules, and a phenomenon of plasmolysis was found in a number of companion cells, indicating a symplastic isolation between SE/CC complex and its surrounding parenchyma cells during this phase. The symplastic isolation between the whole phloem and its surrounding photoassimilate sink_cells during the early developmental stages shifted to a symplastic isolation within the phloem during the ripening phase, and thus the symplastic pathway of sugar unloading from SE/CC complex during the early development stages should be replaced by a dominant apoplastic unloading pathway from SE/CC complex in concordance.展开更多
[Objective] The aim was to promote color wheat industrialization and meet the demand of people on nutritious grain, making both natural and safe food possible. [Method] Hardness indices of wheat were measured and laye...[Objective] The aim was to promote color wheat industrialization and meet the demand of people on nutritious grain, making both natural and safe food possible. [Method] Hardness indices of wheat were measured and layering peeling and milling technology was adopted to explore nutrients distribution in color wheat and effect of hardness on milling of wheat layers. [Result] The results indicated that total content of amino acid in color wheat was higher than that of common wheat by 13.91%-23.32%; Zhongpu Black 1 and Zhongpu Green 1 exceeded common wheat in Zn, Fe and Ca, but Zhongpu Purple 1 was generally lower; Zhongpu Green 1 was significantly higher in Fe and Ca by 371.80% and 102.86%, respectively. Mean- while, it was found that nutrients distribution of color wheat was similar to that of common ,one, namely, pericarp, testa, aleurone layer and embryo were abundant with nutrients. In addition, color wheat was concluded nutritious one and milling in- dustrialization of wheat layers could be achieved through layer-milling and separation technology. Furthermore, wheat hardness was proved the key element influencing milling of wheat layers. [Conclusion] The research set an example for nutrition development and utilization of color wheat.展开更多
The seed shadow of oak ( Quercus liaotungensis Koidz.) was investigated in a broad_leaved deciduous forest in Dongling Mountain in 1997. The seed rain patterns under oak tree crown for three out of four oak trees fit...The seed shadow of oak ( Quercus liaotungensis Koidz.) was investigated in a broad_leaved deciduous forest in Dongling Mountain in 1997. The seed rain patterns under oak tree crown for three out of four oak trees fit quadratic distribution, with high coefficients of determination. For each of the four trees selected in this study the seed rain size estimated from the viable acorns collected from the traps deployed under the crown was low, ranging from 26 to 259. For each of the four oak trees, the average density of the seed rain under oak tree crown ranged from 0.76 to 7.26 seeds/m 2. The average seed rain density estimated from the acorns in the traps deployed randomly in the field was 1.57 seeds/m 2. After all viable acorns fell, the acorn ground density estimated from the acorns in the quadrats was 0.13 seeds/m 2, but no viable acorns were found on the ground under the tree crown of the four oak trees, although the area under the crown was over 5 folds than the area of the combined quadrats. These results indicated that a large number of acorns was removed or predated by vertebrates once the acorns fell on the ground and acorns predation was more intensive in the sites directly under the parent trees than the sites away from the parent trees; this supports the distance_dependent hypothesis. Of the total acorns of all four oak trees, the viable acorns only accounted for 18.1%, and 17.8% for acorns infected by insect larvae, 12.1% for immature acorns, 3.6% for decayed acorns, and the acorns predated by rodent directly in the crown was the highest, accounting for 48.4%. The proportion of acorns predated by animals including vertebrates and invertebrates amounts up to 78.3%, indicating that acorn predation by animals is a limiting factor affecting acorn survival before seed dispersal. The sustained time of viable acorn fall ranged from September 8 to October 3 for the four oak trees, with the peak between 16th and 26th September. The number of acorns was not significantly different among the four directions around the trunk base.展开更多
The separation of Eu^3 ＋is studied with a dispersion combined liquid membrane（DCLM）,in which polyvinylidene fluoride membrane（PVDF）is used as the liquid membrane support,dispersion solution containing HCl solutio...The separation of Eu^3 ＋is studied with a dispersion combined liquid membrane（DCLM）,in which polyvinylidene fluoride membrane（PVDF）is used as the liquid membrane support,dispersion solution containing HCl solution as the stripping solution,and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester（P507）dissolved in kerosene as the membrane solution.The effects of pH value,initial concentration of Eu3 ＋and different ionic strength in the feed phase,volume ratio of membrane solution to stripping solution,concentration of HCl solution, concentration of carrier,different stripping agents in the dispersion phase on the separation are investigated.The optimum condition for separation of Eu3 ＋is that concentration of HCl solution is 4.0 mol·L 1,concentration of carrier is 0.16 mol·L 1,and volume ratio of membrane solution to stripping solution is 30︰30 in the dispersion phase, and pH value is 4.2 in the feed phase.The ionic strength has no significant effect on separation of Eu3 ＋.Under the optimum condition,when the initial concentration of Eu3 ＋is 0.8×10 4mol·L 1,the separation percentage of Eu 3＋is 95.3%during the separation time of 130 min.The kinetic equation is developed in terms of the law of mass diffusion and the theory of interface chemistry.The diffusion coefficient of Eu3 ＋in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and their values are 1.48×10 7m 2·s 1and 36.6μm,respectively.The results obtained are in good agreement with literature data.展开更多
A new configuration of coalescence-dispersed pulsed-sieve-plate extraction column (CDPSEC) was developed, and the mass transfer and axial mixing characteristics were evaluated with the two-point dynamic method.The inf...A new configuration of coalescence-dispersed pulsed-sieve-plate extraction column (CDPSEC) was developed, and the mass transfer and axial mixing characteristics were evaluated with the two-point dynamic method.The influence of operation conditions was discussed with experimental results, showing that the mass transfer performance of CDPSEC mainly depends on the energy input and the holdup of dispersed phase. Higher energy input results in higher holdup of the dispersed phase, the axial mixing of the continuous phase is suppressed, and the true height of mass transfer unit decreases markedly. On the other hand, higher energy input leads to more serious forward mixing of the dispersed phase, so the energy input should be limited. Accordingly the operation conditions were divided into two regions, and empirical correlations for predicting the mass transfer and axial mixing characteristics in different regions with a satisfactory accuracy were suggested.展开更多
The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great difference...The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great differences,static melt crystallization was applied to separate and purify durene from its isomers.Crystallization experiments were carried out under various operating conditions.The effects of cooling rate,crystallization temperature,sweating temperature and sweating time on the yield and purity of crystal were investigated.Orthogonal experimental design method was adopted to analyze the factors that may affect the yield of durene.Under the optimal crystallization conditions,the purity of durene could reach as high as 99.06%with the yield of 75.3%through one crystallization process.By fitting purification data based on sweating time in isothermal operations,the purification rate coefficient was obtained.展开更多
Poly （vinyl butyral） （PVB） hollow fiber membranes were fabricated via thermally induced phase separation （TIPS）. The effects of coagulation bath temperature （CBT） on the structure and performance of membranes ...Poly （vinyl butyral） （PVB） hollow fiber membranes were fabricated via thermally induced phase separation （TIPS）. The effects of coagulation bath temperature （CBT） on the structure and performance of membranes were investigated in detail. The morphologies of the membranes were studied by scanning electron microscopy （SEM）, the performances of water permeability, rejection, breaking strength and elongation were measured, respectively. The results indicate that all the membranes have the asymmetric morphology and the thickness of the skin layer decreases and the pore size of the outer layer increases with the increase of CBT. The permeability of membranes prepared at air gap 1.0 cm and take-up speed 0.253 m/s increases from 1.047×10-7 to 5.909×10-7 m3/（m2·s-kPa） with the CBT increasing from 20 ℃ to 40℃, and sharply increases to 35.226×10 7 m3/（m2.s.kPa）once the CBT arrives at 50 ℃. While the carbonic ink rejections have no significant decrease, totally exceed 98%, but that of acid-maleic acid copolymer greatly decreases with the increase of CBT. Both the breaking strength and elongation decrease with the increase of CBT.展开更多
[Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin. Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid rati...[Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin. Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid ratio and pH value on the extraction yield of polysaccharide from pumpkin. [Method] The best enzyme ratio and extraction conditions for complex enzymes extraction were determined through orthogonal tests. Scavenging ·OH and O-2 activities of pumpkin polysaccharides were also investigated by salicylic acid and improved self-oxidation of o-pheno methods respectively. [Results] The results showed that the biggest extraction yield of polysaccharide from pumpkin can be got when adding 1% cellulose enzyme,1.5% pectinase,1.0% papain and Na2HPO4-citric acid buffer solution (pH was 4.6),and oscillating for 30 min under water at 40 ℃ with the solid-liquid ratio of 1:30. In addition,pumpkin polysaccharides had a strong activity of eliminating ·OH,but very weak activity to scavenge O-2. [Conclusion] This study provided basic data for research and application of Pumpkin polysaccharide.展开更多
Heavy-medium cyclones are widely used to upgrade run-of-mine coal.But the understanding of flow in a cyclone containing a dense medium is still incomplete.By introducing turbulent diffusion into calculations of centri...Heavy-medium cyclones are widely used to upgrade run-of-mine coal.But the understanding of flow in a cyclone containing a dense medium is still incomplete.By introducing turbulent diffusion into calculations of centrifugal settling a theoretical distribution function giving the density field can be deduced.Qualitative analysis of the density field in every part of a cylindrical cyclone suggests an optimum design that has exhibited good separation effectiveness and anti-wear performance when in commercial operation.展开更多
文摘[Objective]The aim was to isolate and identify the pathogen causing black spot disease in guava（Psidium guajava）,so as to determine its taxonomic status.[Method]The fungus was identified by determining its pathogenicity,observing its morphology characteristics and analyzing its ITS sequence.[Result]The pathogen causing black spot disease in guava was a strain of Guignardia mangiferae.[Conclusion]This study will provide theoretical basis for curing black spot disease of guava.
文摘In this study, Ficus carica L. ‘Masui Dauphine＇ was used as the experi- mental material to investigate the effects of explant type, basal medium, hormone types and concentrations on in vitro rapid propagation of‘Masui Dauphine＇. Accord- ing to the results, the most suitable explants for in vitro rapid propagation of ‘Masui Dauphine＇ were axillary buds and the best medium was modified MS ＋ 1.0 mg/L 6-BA ＋ 0. 05 mg/L NAA ＋ 1.0 mg/L GA3 ＋ 20 mg/L sucrose ＋ 7 mg/L agar, pH 5.8. This study provided scientific basis for barge-scale cultivation of‘Masui Dauphine ＇.
文摘The ultrastructure and intercellular connection of the sugar unloading zone (i.e. the phloem in the dorsal vascular bundle and the phloem_surrounding the assimilate sink_cells) of grape ( Vitis vinifera× V. labrusca cv. Jingchao) berry was observed via transmission electron microscopy. The results showed that during the early developmental stages of grape berry, numerous plasmodesmata were found in the phloem between sieve element (SE) and companion cell (CC), between SE/CC complexes, between SE/CC complex and phloem parenchyma cell and in between phloem parenchyma cells, which made the phloem a symplastic integration, facilitating sugar unloading from sieve elements into both companion cells and phloem parenchyma cells via a symplastic pathway. On the contrary, there was almost no plasmodesma between phloem and its surrounding flesh photoassimilate sink_cells, neither in between the flesh photoassimilate sink_cells giving rise to a symplastic isolation both between phloem and its surrounding flesh photoassimilate sink_cells, as well as among the flesh photoassimilate sink_cells. This indicated that both the sugar unloading from phloem and postphloem transport of sugars should be mainly via an apoplastic pathway. During the ripening stage, most of the plasmodesmata between SE/CC complex and the surrounding phloem parenchyma cells were shown to be blocked by the electron_opaque globules, and a phenomenon of plasmolysis was found in a number of companion cells, indicating a symplastic isolation between SE/CC complex and its surrounding parenchyma cells during this phase. The symplastic isolation between the whole phloem and its surrounding photoassimilate sink_cells during the early developmental stages shifted to a symplastic isolation within the phloem during the ripening phase, and thus the symplastic pathway of sugar unloading from SE/CC complex during the early development stages should be replaced by a dominant apoplastic unloading pathway from SE/CC complex in concordance.
基金Supported by National Natural Science Foundtion of China in2011(31171789)~~
文摘[Objective] The aim was to promote color wheat industrialization and meet the demand of people on nutritious grain, making both natural and safe food possible. [Method] Hardness indices of wheat were measured and layering peeling and milling technology was adopted to explore nutrients distribution in color wheat and effect of hardness on milling of wheat layers. [Result] The results indicated that total content of amino acid in color wheat was higher than that of common wheat by 13.91%-23.32%; Zhongpu Black 1 and Zhongpu Green 1 exceeded common wheat in Zn, Fe and Ca, but Zhongpu Purple 1 was generally lower; Zhongpu Green 1 was significantly higher in Fe and Ca by 371.80% and 102.86%, respectively. Mean- while, it was found that nutrients distribution of color wheat was similar to that of common ,one, namely, pericarp, testa, aleurone layer and embryo were abundant with nutrients. In addition, color wheat was concluded nutritious one and milling in- dustrialization of wheat layers could be achieved through layer-milling and separation technology. Furthermore, wheat hardness was proved the key element influencing milling of wheat layers. [Conclusion] The research set an example for nutrition development and utilization of color wheat.
文摘The seed shadow of oak ( Quercus liaotungensis Koidz.) was investigated in a broad_leaved deciduous forest in Dongling Mountain in 1997. The seed rain patterns under oak tree crown for three out of four oak trees fit quadratic distribution, with high coefficients of determination. For each of the four trees selected in this study the seed rain size estimated from the viable acorns collected from the traps deployed under the crown was low, ranging from 26 to 259. For each of the four oak trees, the average density of the seed rain under oak tree crown ranged from 0.76 to 7.26 seeds/m 2. The average seed rain density estimated from the acorns in the traps deployed randomly in the field was 1.57 seeds/m 2. After all viable acorns fell, the acorn ground density estimated from the acorns in the quadrats was 0.13 seeds/m 2, but no viable acorns were found on the ground under the tree crown of the four oak trees, although the area under the crown was over 5 folds than the area of the combined quadrats. These results indicated that a large number of acorns was removed or predated by vertebrates once the acorns fell on the ground and acorns predation was more intensive in the sites directly under the parent trees than the sites away from the parent trees; this supports the distance_dependent hypothesis. Of the total acorns of all four oak trees, the viable acorns only accounted for 18.1%, and 17.8% for acorns infected by insect larvae, 12.1% for immature acorns, 3.6% for decayed acorns, and the acorns predated by rodent directly in the crown was the highest, accounting for 48.4%. The proportion of acorns predated by animals including vertebrates and invertebrates amounts up to 78.3%, indicating that acorn predation by animals is a limiting factor affecting acorn survival before seed dispersal. The sustained time of viable acorn fall ranged from September 8 to October 3 for the four oak trees, with the peak between 16th and 26th September. The number of acorns was not significantly different among the four directions around the trunk base.
基金Supported by the National Natural Science Foundation of China（90401009） the Foundation for Planning Project of West Action of Chinese Academy of Sciences（KZCX2-XB2-13） the Research Fund for Excellent Doctoral Thesis of Xi’an University of Technology（602-210805）
文摘The separation of Eu^3 ＋is studied with a dispersion combined liquid membrane（DCLM）,in which polyvinylidene fluoride membrane（PVDF）is used as the liquid membrane support,dispersion solution containing HCl solution as the stripping solution,and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester（P507）dissolved in kerosene as the membrane solution.The effects of pH value,initial concentration of Eu3 ＋and different ionic strength in the feed phase,volume ratio of membrane solution to stripping solution,concentration of HCl solution, concentration of carrier,different stripping agents in the dispersion phase on the separation are investigated.The optimum condition for separation of Eu3 ＋is that concentration of HCl solution is 4.0 mol·L 1,concentration of carrier is 0.16 mol·L 1,and volume ratio of membrane solution to stripping solution is 30︰30 in the dispersion phase, and pH value is 4.2 in the feed phase.The ionic strength has no significant effect on separation of Eu3 ＋.Under the optimum condition,when the initial concentration of Eu3 ＋is 0.8×10 4mol·L 1,the separation percentage of Eu 3＋is 95.3%during the separation time of 130 min.The kinetic equation is developed in terms of the law of mass diffusion and the theory of interface chemistry.The diffusion coefficient of Eu3 ＋in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and their values are 1.48×10 7m 2·s 1and 36.6μm,respectively.The results obtained are in good agreement with literature data.
文摘A new configuration of coalescence-dispersed pulsed-sieve-plate extraction column (CDPSEC) was developed, and the mass transfer and axial mixing characteristics were evaluated with the two-point dynamic method.The influence of operation conditions was discussed with experimental results, showing that the mass transfer performance of CDPSEC mainly depends on the energy input and the holdup of dispersed phase. Higher energy input results in higher holdup of the dispersed phase, the axial mixing of the continuous phase is suppressed, and the true height of mass transfer unit decreases markedly. On the other hand, higher energy input leads to more serious forward mixing of the dispersed phase, so the energy input should be limited. Accordingly the operation conditions were divided into two regions, and empirical correlations for predicting the mass transfer and axial mixing characteristics in different regions with a satisfactory accuracy were suggested.
基金Supported by the National Natural Science Foundation of China(21176172)Top Talents Program of Yunnan Province,China(2011HA010)
文摘The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great differences,static melt crystallization was applied to separate and purify durene from its isomers.Crystallization experiments were carried out under various operating conditions.The effects of cooling rate,crystallization temperature,sweating temperature and sweating time on the yield and purity of crystal were investigated.Orthogonal experimental design method was adopted to analyze the factors that may affect the yield of durene.Under the optimal crystallization conditions,the purity of durene could reach as high as 99.06%with the yield of 75.3%through one crystallization process.By fitting purification data based on sweating time in isothermal operations,the purification rate coefficient was obtained.
基金Project(21176264)supported by the National Natural Science Foundation of ChinaProject(11JJ2010)supported by the Hunan Provincial Natural Science Foundation of China
文摘Poly （vinyl butyral） （PVB） hollow fiber membranes were fabricated via thermally induced phase separation （TIPS）. The effects of coagulation bath temperature （CBT） on the structure and performance of membranes were investigated in detail. The morphologies of the membranes were studied by scanning electron microscopy （SEM）, the performances of water permeability, rejection, breaking strength and elongation were measured, respectively. The results indicate that all the membranes have the asymmetric morphology and the thickness of the skin layer decreases and the pore size of the outer layer increases with the increase of CBT. The permeability of membranes prepared at air gap 1.0 cm and take-up speed 0.253 m/s increases from 1.047×10-7 to 5.909×10-7 m3/（m2·s-kPa） with the CBT increasing from 20 ℃ to 40℃, and sharply increases to 35.226×10 7 m3/（m2.s.kPa）once the CBT arrives at 50 ℃. While the carbonic ink rejections have no significant decrease, totally exceed 98%, but that of acid-maleic acid copolymer greatly decreases with the increase of CBT. Both the breaking strength and elongation decrease with the increase of CBT.
基金Supported by the Key Scientific and Technological Project of Henan Province (102102110157)the Scientific Research Found Project of Henan University of Urban Construction (2010JZD008)~~
文摘[Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin. Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid ratio and pH value on the extraction yield of polysaccharide from pumpkin. [Method] The best enzyme ratio and extraction conditions for complex enzymes extraction were determined through orthogonal tests. Scavenging ·OH and O-2 activities of pumpkin polysaccharides were also investigated by salicylic acid and improved self-oxidation of o-pheno methods respectively. [Results] The results showed that the biggest extraction yield of polysaccharide from pumpkin can be got when adding 1% cellulose enzyme,1.5% pectinase,1.0% papain and Na2HPO4-citric acid buffer solution (pH was 4.6),and oscillating for 30 min under water at 40 ℃ with the solid-liquid ratio of 1:30. In addition,pumpkin polysaccharides had a strong activity of eliminating ·OH,but very weak activity to scavenge O-2. [Conclusion] This study provided basic data for research and application of Pumpkin polysaccharide.
基金supported by the National Natural Science Foundation of China(No.50921002)
文摘Heavy-medium cyclones are widely used to upgrade run-of-mine coal.But the understanding of flow in a cyclone containing a dense medium is still incomplete.By introducing turbulent diffusion into calculations of centrifugal settling a theoretical distribution function giving the density field can be deduced.Qualitative analysis of the density field in every part of a cylindrical cyclone suggests an optimum design that has exhibited good separation effectiveness and anti-wear performance when in commercial operation.
