[Objective] This study was conducted to construct a super-high yield population of Japnica rice in cold regions of North China and to explore its characteristics. [Method] The super rice variety Longjing 21 was select...[Objective] This study was conducted to construct a super-high yield population of Japnica rice in cold regions of North China and to explore its characteristics. [Method] The super rice variety Longjing 21 was selected as the experimental material. Different row spacing(two levels), plant spacing(three levels) and seedling number per hill(three levels) were designed in field trials. Then, the growth stages,dry matter accumulation, leaf area, yield and yield components of these different treatments were measured. [Result] Rice yield had significantly negative correlation with plant spacing and row spacing, but no significant correlation with seedling number per hill. Rice yield was mainly affected by plant spacing, and less affected by seedling number per hill. The best recommended specifications for plant spacing of super rice variety Longjing 21 were 24 cm for row spacing, 12 cm for plant spacing and five seedlings per hill, and the expected yield was 10 473.0 kg/hm^2.The increased number of total spikelets(4.5×108hm2or more) in populations was the major reason for high yield. Super-high yield populations had fewer tillers at the early growth stage and achieved the expected number of productive tillers at critical leaf-age(June 25), and tiller number peaked at jointing stage(July 6) and was about 1.2 times of the expected number. The percentage of productive tillers in total tillers of super-high yield population was more than 85% at heading stage. At middle growth stage(from jointing to heading stage), the dry matter accumulation, leaf area index(LAI) at heading stage, effective leaf area, spikelet number of population,spikelet number per leaf area unit(cm2), and culm-sheath weight per stem of super-high yield population were significantly higher than those of other populations.At late growth stage(from heading to maturity stage), the leaf area decreasing rate of super-high yield population was significantly smaller than that of other populations. At late growth stage(from heading to maturity stage), the leaf area decreasing rate, crop growth rate, net assimilation rate, biomass accumulation, number of filled grains per leaf area unit(cm^2) and grain weight per leaf area unit(cm^2) of high-yield population were significantly higher than those of other populations. Output and translocation of dry matter(weight per stem and sheath and total filling rate at maturity) from heading to milky stage of super-high yield population were significantly higher than those of other populations. [Conclusion] The characteristics of superhigh yield rice in cold region of North China are enriching the amount of actual filling of sink through improving photosynthetic efficiency from heading to maturity stage on the basis of enough panicle numbers.展开更多
Dehydrated sorghum flour ("ogi") is useful as additional ingredient in certain food and pharmaceutical formulation, this could be obtained by soaking sorghum in water for 3 to 4 days, wet milling the soaked materi...Dehydrated sorghum flour ("ogi") is useful as additional ingredient in certain food and pharmaceutical formulation, this could be obtained by soaking sorghum in water for 3 to 4 days, wet milling the soaked material, and fermentation for another 3 to 4 days. Typically, the fermented product is boiled into a pap or cooked into a stiff porridge. However, the fermented product can not be easily handled or stored and does not have a long shelf life (typically less than a week). Dehydrating the fermented product into flour is one of the ways that is being employed to overcome these problems. Equilibrium moisture content (EMC) of dehydrated sorghum flour (aka "ogi") was therefore determined at two temperatures of 25℃ and 40℃ and four salt solutions. Zinc chloride (ZnCl2), potassium acetate (KC2H3O2), calcium chloride (CaCl2) and sodium chloride (NaCl) salts were prepared to correspond to equilibrium relative humidities of 10.0% to 75.4%. The moisture sorption characteristics of the sorghum product showed the characteristics S-shaped sorption isotherm curve that is typically obtained for agricultural products. The equilibrium data and the monomolccular layer moisture content values were estimated using the Brunauer-Emmett-Teller (BET) equation. The moisture content range for optimum storage of the dehydrated sorghum flour lies between 2.84% to 3.69% at 25℃ and 6.84% and 7.67% at 40℃. The information obtained from this study will help in the design and selection of storage and packaging systems for dehydrated sorghum flour.展开更多
Enzymatic hydrolysis of lignocellulose is often considered to be the major economic bottleneck of the production process of bioethanol from lignocellulose. It is generally admitted that the most efficient organism for...Enzymatic hydrolysis of lignocellulose is often considered to be the major economic bottleneck of the production process of bioethanol from lignocellulose. It is generally admitted that the most efficient organism for the production ofcellulolytic enzymes is the fungus Trichoderma reesei, mostly due to its high secretion capacity. Unfortunately, this fungus secretes very low concentrations of β-glucosidase, thereby often requiring β-glucosidase supplementation for complete cellulose hydrolysis. It is especially important to have sufficient quantities of β-glucosidase in order to prevent inhibition of cellobiohydrolases by cellobiose. In order to optimize the produced cocktail, a more efficient β-glucosidase was cloned into T. reesei CL847 strain. The new strain, called CL847 TR3002, secretes the evolved β-glucosidase and was tested for cellulase production in laboratory-scale reactors. Its growth kinetics and cellulase production were characterized using fed-batch and chemostat modes under various culture conditions. The cellulase activities of the evolved strain were compared with activities of the parent strain. In addition, hydrolysis of a steam exploded wheat straw was performed at three different enzyme-loading levels (5 mg/g, 10 mg/g and 20 mg/g of dry matter) and a new kinetic model was developed.展开更多
This paper presents a nonlinear multidimensional scaling model, called kernelized fourth quantifica- tion theory, which is an integration of kernel techniques and the fourth quantification theory. The model can deal w...This paper presents a nonlinear multidimensional scaling model, called kernelized fourth quantifica- tion theory, which is an integration of kernel techniques and the fourth quantification theory. The model can deal with the problem of mineral prediction without defining a training area. In mineral target prediction, the pre-defined statistical cells, such as grid cells, can be implicitly transformed using kernel techniques from input space to a high-dimensional feature space, where the nonlinearly separable clusters in the input space are ex- pected to be linearly separable. Then, the transformed cells in the feature space are mapped by the fourth quan- tifieation theory onto a low-dimensional scaling space, where the sealed cells can be visually clustered according to their spatial locations. At the same time, those cells, which are far away from the cluster center of the majority of the sealed cells, are recognized as anomaly cells. Finally, whether the anomaly cells can serve as mineral potential target cells can be tested by spatially superimposing the known mineral occurrences onto the anomaly ceils. A case study shows that nearly all the known mineral occurrences spatially coincide with the anomaly cells with nearly the smallest scaled coordinates in one-dimensional sealing space. In the case study, the mineral target cells delineated by the new model are similar to those predicted by the well-known WofE model.展开更多
基金Supported by National Key Technology Research and Development Program of China(2011BAD16B11-02YJ01,2012BAD04B01-02)Key Science and Technology Program of Heilongjiang Province+2 种基金China(GA13B101)Heilongjiang Postdoctoral Sustentation Fund(LBH-Z10038)the Funds of Heilongjiang Academy of Agricultural Sciences for Distinguished Young Scholars(2014)~~
文摘[Objective] This study was conducted to construct a super-high yield population of Japnica rice in cold regions of North China and to explore its characteristics. [Method] The super rice variety Longjing 21 was selected as the experimental material. Different row spacing(two levels), plant spacing(three levels) and seedling number per hill(three levels) were designed in field trials. Then, the growth stages,dry matter accumulation, leaf area, yield and yield components of these different treatments were measured. [Result] Rice yield had significantly negative correlation with plant spacing and row spacing, but no significant correlation with seedling number per hill. Rice yield was mainly affected by plant spacing, and less affected by seedling number per hill. The best recommended specifications for plant spacing of super rice variety Longjing 21 were 24 cm for row spacing, 12 cm for plant spacing and five seedlings per hill, and the expected yield was 10 473.0 kg/hm^2.The increased number of total spikelets(4.5×108hm2or more) in populations was the major reason for high yield. Super-high yield populations had fewer tillers at the early growth stage and achieved the expected number of productive tillers at critical leaf-age(June 25), and tiller number peaked at jointing stage(July 6) and was about 1.2 times of the expected number. The percentage of productive tillers in total tillers of super-high yield population was more than 85% at heading stage. At middle growth stage(from jointing to heading stage), the dry matter accumulation, leaf area index(LAI) at heading stage, effective leaf area, spikelet number of population,spikelet number per leaf area unit(cm2), and culm-sheath weight per stem of super-high yield population were significantly higher than those of other populations.At late growth stage(from heading to maturity stage), the leaf area decreasing rate of super-high yield population was significantly smaller than that of other populations. At late growth stage(from heading to maturity stage), the leaf area decreasing rate, crop growth rate, net assimilation rate, biomass accumulation, number of filled grains per leaf area unit(cm^2) and grain weight per leaf area unit(cm^2) of high-yield population were significantly higher than those of other populations. Output and translocation of dry matter(weight per stem and sheath and total filling rate at maturity) from heading to milky stage of super-high yield population were significantly higher than those of other populations. [Conclusion] The characteristics of superhigh yield rice in cold region of North China are enriching the amount of actual filling of sink through improving photosynthetic efficiency from heading to maturity stage on the basis of enough panicle numbers.
文摘Dehydrated sorghum flour ("ogi") is useful as additional ingredient in certain food and pharmaceutical formulation, this could be obtained by soaking sorghum in water for 3 to 4 days, wet milling the soaked material, and fermentation for another 3 to 4 days. Typically, the fermented product is boiled into a pap or cooked into a stiff porridge. However, the fermented product can not be easily handled or stored and does not have a long shelf life (typically less than a week). Dehydrating the fermented product into flour is one of the ways that is being employed to overcome these problems. Equilibrium moisture content (EMC) of dehydrated sorghum flour (aka "ogi") was therefore determined at two temperatures of 25℃ and 40℃ and four salt solutions. Zinc chloride (ZnCl2), potassium acetate (KC2H3O2), calcium chloride (CaCl2) and sodium chloride (NaCl) salts were prepared to correspond to equilibrium relative humidities of 10.0% to 75.4%. The moisture sorption characteristics of the sorghum product showed the characteristics S-shaped sorption isotherm curve that is typically obtained for agricultural products. The equilibrium data and the monomolccular layer moisture content values were estimated using the Brunauer-Emmett-Teller (BET) equation. The moisture content range for optimum storage of the dehydrated sorghum flour lies between 2.84% to 3.69% at 25℃ and 6.84% and 7.67% at 40℃. The information obtained from this study will help in the design and selection of storage and packaging systems for dehydrated sorghum flour.
文摘Enzymatic hydrolysis of lignocellulose is often considered to be the major economic bottleneck of the production process of bioethanol from lignocellulose. It is generally admitted that the most efficient organism for the production ofcellulolytic enzymes is the fungus Trichoderma reesei, mostly due to its high secretion capacity. Unfortunately, this fungus secretes very low concentrations of β-glucosidase, thereby often requiring β-glucosidase supplementation for complete cellulose hydrolysis. It is especially important to have sufficient quantities of β-glucosidase in order to prevent inhibition of cellobiohydrolases by cellobiose. In order to optimize the produced cocktail, a more efficient β-glucosidase was cloned into T. reesei CL847 strain. The new strain, called CL847 TR3002, secretes the evolved β-glucosidase and was tested for cellulase production in laboratory-scale reactors. Its growth kinetics and cellulase production were characterized using fed-batch and chemostat modes under various culture conditions. The cellulase activities of the evolved strain were compared with activities of the parent strain. In addition, hydrolysis of a steam exploded wheat straw was performed at three different enzyme-loading levels (5 mg/g, 10 mg/g and 20 mg/g of dry matter) and a new kinetic model was developed.
基金supported by National Natural Science Foundation of China (No.40872193)
文摘This paper presents a nonlinear multidimensional scaling model, called kernelized fourth quantifica- tion theory, which is an integration of kernel techniques and the fourth quantification theory. The model can deal with the problem of mineral prediction without defining a training area. In mineral target prediction, the pre-defined statistical cells, such as grid cells, can be implicitly transformed using kernel techniques from input space to a high-dimensional feature space, where the nonlinearly separable clusters in the input space are ex- pected to be linearly separable. Then, the transformed cells in the feature space are mapped by the fourth quan- tifieation theory onto a low-dimensional scaling space, where the sealed cells can be visually clustered according to their spatial locations. At the same time, those cells, which are far away from the cluster center of the majority of the sealed cells, are recognized as anomaly cells. Finally, whether the anomaly cells can serve as mineral potential target cells can be tested by spatially superimposing the known mineral occurrences onto the anomaly ceils. A case study shows that nearly all the known mineral occurrences spatially coincide with the anomaly cells with nearly the smallest scaled coordinates in one-dimensional sealing space. In the case study, the mineral target cells delineated by the new model are similar to those predicted by the well-known WofE model.