Flax(Linum usitatissimum L.)is an important oil crop in the high-altitude arid regions of China.Flaxseed is rich in various nutrients.However,the nutritional qualities of flaxseeds from different producing areas are s...Flax(Linum usitatissimum L.)is an important oil crop in the high-altitude arid regions of China.Flaxseed is rich in various nutrients.However,the nutritional qualities of flaxseeds from different producing areas are still unclear.In this study,the nutritional characteristics of flaxseed from five producing areas in China were investigated.Twenty five nutritional quality indices in flaxseed were analyzed.Subsequently,chemometric methods,including cluster analysis,principal component analysis(PCA)and partial least square discriminant analysis(PLS-DA),were employed to discover the characteristics of nutritional qualities in flaxseeds.The results revealed there are significant differences in nutritional qualities among flaxseeds from different production areas.Six quality indices includingγ-tocopherol,vitamin E,phytosterols,oleic acid,α-linolenic acid,and cycloartenol were susceptible to producing area.In detail,the superiorcharacteristic nutrients of Ningxia flaxseed,Inner Mongolia flaxseed and Hebei flaxseed are vitamin E(17.3 mg/100g),α-linolenic acid(52.6%)and cycloartenol(1738.1 mg/kg),and phytosterols(3032.0 mg/kg),respectively.This study promotes the high-value development and utilization of local flaxseed industry.展开更多
In the late 1970s,the theory of coal-formed gas began to take root,sprout,develop,and improve in China.After decades of development,a complete theoretical system was finally formed.The theory of coal-formed gas points...In the late 1970s,the theory of coal-formed gas began to take root,sprout,develop,and improve in China.After decades of development,a complete theoretical system was finally formed.The theory of coal-formed gas points out that coal measures are good gas source rocks,with gas as the main hydrocarbon generated and oil as the auxiliary.It has opened up a new exploration idea using coal-bearing humic organic matter as the gas source,transforming the theoretical guidance for natural gas exploration in China from“monism”(i.e.oil-type gas)to“dualism”(i.e.coal-formed gas and oil-type gas)and uncovering a new field of natural gas exploration.Before the establishment of the coal-formed gas theory,China was a gas-poor country with low proved gas initially-in-place(merely 2264.33×10^(8)m^(3))and production(137.3×10^(8)m^(3)/a),corresponding to a per capita annual consumption of only 14.37 m^(3).Guided by the theory of coal-formed gas,the natural gas industry of China has developed rapidly.By the end of 2023,China registered the cumulative proved gas initially-in-place of 20.90×10^(12)m^(3),an annual gas production of 2343×10^(8)m^(3),and a per capita domestic gas consumption reaching 167.36 m^(3).The cumulative proved reserves initially-in-place and production of natural gas were dominated by coal-formed gas.Owing to this advancement,China has transformed from a gas-poor country to the fourth largest gas producer in the world.The coal-formed gas theory and the tremendous achievements made in natural gas exploration in China under its guidance have promoted China from a gas-poor country to a major gas-producing country in the world.展开更多
Promoting the deep integration of advanced manufacturing and producer services is not only a key path for metropolitan to climb the global value chain,but also an important new driving force for optimizing urban spati...Promoting the deep integration of advanced manufacturing and producer services is not only a key path for metropolitan to climb the global value chain,but also an important new driving force for optimizing urban spatial structure.Based on the two dimen-sions of industrial linkage and spatial co-agglomeration from the perspective of industrial integration,taking Beijing,China as a case,using industrial input-output data,micro-enterprise spatial data,and methods such as industrial linkage model,standard deviation el-lipse,and spatial similarity coefficient,this study explores the coupling relationship between industrial linkage and spatial co-agglomer-ation of advanced manufacturing and producer services from 2007 to 2020.The results demonstrate that:1)the industrial linkage between advanced manufacturing and producer services in Beijing has an upward trend,in which the business services have the most significant improvement,in which the business services have the most improvement while the technology services have the most de-crease,but in general,the industrial linkage between the two industries shows a low level.2)Producer services were more spatially clustered than advanced manufacturing,and the degree of spatial co-agglomeration of the two also showed an increasing trend,with strong regional and industrial heterogeneity characteristics,among which the pairing industry involving commerce services and techno-logy services had a more obvious improvement.3)The coupling analysis found that the spatial dependence between advanced manufac-turing and producer services decreased,showing a weak positive correlation and a decreasing trend between industrial linkage and spa-tial co-agglomeration;the heterogeneity among subdivision pairs is prominent,and the strong correlation between industries does not mean that there is an inevitable spatial co-agglomeration.4)Based on the differences in coupling relationships and influence mechan-isms,four coupling modes are identified:H-H type,H-L type,L-L type,and L-H type.Finally,this study proposes three policy implica-tions for the integration of advanced manufacturing and producer services in metropolitan areas.展开更多
We report the observation of Zeeman splitting in multiple spectral lines emitted by a laser-produced,magnetized plasma(1–3×10^(18)cm^(-3),1–15 eV)in the context of a laboratory astrophysics experiment under a c...We report the observation of Zeeman splitting in multiple spectral lines emitted by a laser-produced,magnetized plasma(1–3×10^(18)cm^(-3),1–15 eV)in the context of a laboratory astrophysics experiment under a controlled magneticfield up to 20T.Nitrogen lines(NII)in the visible range were used to diagnose the magneticfield and plasma conditions.This was performed by coupling our data with(563–574 nm)the Stark–Zeeman line-shape code PPPB.The excellent agreement between experiment and simulations paves the way for a non-intrusive experimental platform to get time-resolved measurements of the local magneticfield in laboratory plasmas.展开更多
A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors (e.g., eco...A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors (e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance). In this study, an interval-probabilistic agricultural production structure optimization model (IPAPSOM) is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying (or risk of violating) system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty.展开更多
[Objective] The paper was to establish embryonic stem cell system of goats. [Method] Numerous primordial germ cell colonies were derived from gonadal ridge and the surrounding tissues in 20 millimeter fetuses of down ...[Objective] The paper was to establish embryonic stem cell system of goats. [Method] Numerous primordial germ cell colonies were derived from gonadal ridge and the surrounding tissues in 20 millimeter fetuses of down producing goat. Primordial germ cells and goats embryonic fibroblasts obtained from conceptus of equivaient gestational age were co-cultured. [Result] The colonies showed some characteristics of embryonic stem cells, such as the morphology of nest-like, they continued to be AKP positive and the ability to be continuously passed [Conclusion] These cells were pluripotent and ES-like cells.展开更多
The microbial community structure and functionally distinct groups in three kinds of produced water samples from the shallow,mesothermic and low-salinity Daqing oil reservoir were systematically evaluated using both c...The microbial community structure and functionally distinct groups in three kinds of produced water samples from the shallow,mesothermic and low-salinity Daqing oil reservoir were systematically evaluated using both culture-dependent and culture-independent methods.Sequence analysis of the 16S rRNA genes indicated that the bacterial library was dominated by Acinetobacter and Arcobacter and the archaeal community was dominated by Methanosaeta and Methanolinea.Two isolated methanogens were closely related with Methanothermobacter thermautotrophicus and Methanoculleus receptaculi.The fermentative bacteria were identified as Pseudomonas,Haloanaerobium,Alcalibacter,Arcobacter,and Pannonibacter.The predominant nitrate-reducing bacteria fell within the genus Pseudomonas.The dominant members of the cultured hydrocarbon-oxidizing bacteria were phylogenetically associated with Micrococcus,Pseudomonas,and Bacillus.Enrichments of biosurfactants and biopolymer producing groups mainly yielded Pseudomonas,Bacillus,and Acenitobacter-related members.The functional groups related to polymer degradation were also affiliated with Pseudomonas and Bacillus.Results from this study provide the fresh insight into the diversity of microbial communities in Daqing petroleum reservoirs.The vast pool of functional strains retrieved in this study was presumed to include the promising strains that could be applied in microbial-enhanced oil recovery in future.展开更多
Based on the data from 1998 to 2005,area rainfall,flow of main hydrologic stations in Duhe River and upstream water level of the dam of Huanglongtan Reservoir in the lower reaches of Duhe River were analyzed,and the s...Based on the data from 1998 to 2005,area rainfall,flow of main hydrologic stations in Duhe River and upstream water level of the dam of Huanglongtan Reservoir in the lower reaches of Duhe River were analyzed,and the standard of flood-producing rainstorm in Duhe River was given,while temporal and spatial distribution and circulation flow situation characteristic of flood-producing rainstorm in Duhe River were studied.The results showed that the flood-producing rainstorm in Duhe River was mainly continuous intensive precipitation with the characteristic of long duration.There was most rainfall in Zhuxiquan River,Zhushanguandu River and southwest part of the middle and upper reaches of Duhe River,and next came Zhuxi River.Flood-producing rainstorm occurred in Duhe River with some favorable circulation features.For example,it was more favorable in the west Pacific subtropical high,and the convergence zone at northeast-southwest direction was formed between subtropical high and continental high pressure at 700 hPa,while southwest vortex moved eastward.Low pressure system at 850 hPa in south part of plateau developed and moved eastward to Chongqing region and formed low vortex or shear near Duhe River basin.Moreover,the characteristics of physical quantity field were analyzed,the results showed that temperature in plateau area and the south area of Duhe River basin increased obviously before rainstorm,and east pathway was the main path of cold air which affected flood-producing rainstorm in Duhe River.There was a θse intensive belt with NEE-SWW direction at 30°-40° N at 925-500 hPa,and moisture convergence was beneficial to the occurrence of rainstorm in Duhe River.展开更多
This article conducts empirical analysis of rice growers' behavior of productive capital input and the influencing factors,using the input-output survey data concerning rice growing by 305 peasant households in 20...This article conducts empirical analysis of rice growers' behavior of productive capital input and the influencing factors,using the input-output survey data concerning rice growing by 305 peasant households in 2009 in Huanan County and Huachuan County,Jiamusi City,Heilongjiang Province.I use Logit model to carry out econometric test of factors influencing the possibility of fixed productive investment.The test results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level,peasant households' expectation of the minimum purchase price of rice,have significant effect on whether to conduct fixed productive investment,whether there are disasters has no significant effect on the scale of peasant households' productive investment.Then I use Tobit model to carry out econometric test of factors influencing the scale of productive capital input.The results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level and family housing value,peasant households' expectation of the minimum purchase price of rice,whether there are disasters,have significant effect on the scale of peasant households' productive investment.On the basis of model test results,in order to promote the rice growers to increase fixed productive input and increase productive capital input,rational recommendations are put forward as follows:raising the minimum purchase price of rice,scaling up rice growing,making every effort to promote the educational level of rice growers,ensuring that the rice growers obtain productive capital input loans timely.展开更多
A strain of hydrogen producing bacteria was immobilized by polyvinyl alcohol-boric acid method, with the addition of a small amount of calcium alginate. The immobilized cells were insensitive to the presence of traces...A strain of hydrogen producing bacteria was immobilized by polyvinyl alcohol-boric acid method, with the addition of a small amount of calcium alginate. The immobilized cells were insensitive to the presence of traces of O2. Moreover, the immobilized cells increased both the evolution rate and the yield of hydrogen production. Batch experiments with a medium containing 10 g/L glucose demonstrated the yields of hydrogen production by the immobilized and free cells were 2.14 mol/mol glucose and 1.69 mol/mol glucose, respectively. In continuous cultures at medium retention time of 2.0 h, the yield and the evolution rate of hydrogen production by the immobilized cells were 2.31 mol/mol glucose and 1 435.4 ml/(L·h) respectively. However, at medium retention time of 6.0 h, the yield and the evolution rate of hydrogen production by free cells were only 1.75 mol/mol glucose and 362.9 ml/(L·h), respectively.展开更多
The virulent factors of Escherichia coil (E.cofi) play an important role in the process of pathopoiesis. The study aimed to compare drug-resistant genes and virulence genes between extended spectrum β-1actamases (...The virulent factors of Escherichia coil (E.cofi) play an important role in the process of pathopoiesis. The study aimed to compare drug-resistant genes and virulence genes between extended spectrum β-1actamases (ESBLs)-producing E.coli and non-ESBLs-producing E.cofi to provide a reference for physicians in management of hospital infection. From October 2010 to August 2011,96 drug-resistant strains of E. coli isolated were collected from the specimens in Qingdao Municipal Hospital, Qingdao, China. These bacteria strains were divided into a ESBLs-producing group and a non-ESBLs-producing group. Drug sensitivity tests were performed using the Kirby-Bauer (K-B) method. Disinfectant gene, qacEAl-sull and 8 virulence genes (CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1) were tested by polymerase chain reaction (PCR). Among the 96 E.coli isolates, the ESBLs-producing E.coli comprised 46 (47.9%) strains and the non-ESBLs-producing E.cofi consisted of 50 (52.1%) strains. The detection rates of multiple drug-resistant strain, qacEAl-sull, CNF2, hlyA, eaeA,VT1, est, bfpA, elt, and CNF1 in 46 ESBLs-producing E.coli isolates were 89.1%, 76.1%, 6.5%, 69.6%, 69.6%, 89.1%, 10.9%, 26.1%, 8.7%, and 19.6%, respectively. In the non-ESBLs-producing E.cofi strains, the positive rates of multiple drug-resistant strain, qacEAl-sull, CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1 were 62.0%, 80.0%, 16.0%, 28.0%, 64.0%, 38.0%, 6.0%, 34.0%, 10.0%, and 24.0%, respectively. The difference in the detection rates of multiple drug-resistant strain, hlyA and VT1 between the ESBLs-producing E.cofi strains and the non-ESBLs-producing E.cofi strains was statistically significant (P〈0.05). The positive rate of multiple drug-resistant strains is higher in the ESBLs-producing strains than in the non-ESBLs-producing strains. The expression of some virulence genes hlyA and VT1 varies between the ESBLs-producing strains and the non-ESBLs-producing strains. Increased awareness of clinicians and enhanced testing by laboratories are required to reduce treatment failures and prevent the spread of multiple drug-resistant strains.展开更多
On the basis of defining the producers in the supply chain of agricultural products,the SWOT analysis is adopted to analyze the advantages,disadvantages,opportunities and threats of producers in the supply chain of Ch...On the basis of defining the producers in the supply chain of agricultural products,the SWOT analysis is adopted to analyze the advantages,disadvantages,opportunities and threats of producers in the supply chain of Chinese agricultural products.The paper analyzes the advantages of producers in the supply chain of agricultural products from three aspects including land resources,technology level of producers and input costs.The disadvantages of producers in the supply chain of agricultural products are analyzed from three aspects including scale level,mechanization and technology level and profit level.The opportunities of producers in the supply chain of agricultural products are analyzed from the aspects of laws,policies,capitals and technologies.The threats confronted by the producers in the supply chain of agricultural products are analyzed from foreign producers,negotiation control of supply chain of agricultural chain,environment protection and quality safety standard.On the basis of the analysis,the relevant suggestions on facilitating the interests of producers in the supply chain of Chinese agricultural products are put forward,including fully displaying the advantages of land resources;improving the knowledge and technology level of supply chain of agricultural production;establishing the alliances of producers of agricultural products to expand production scale;improving the quality of agricultural products to satisfy the relevant safety quality standard and environmental protection standard.展开更多
The research conducted investigation and survey on 186 farm households in 2014 and carried out economic evaluation on "planting three to produce four" highyielding project of super hybrid rice. The results showed th...The research conducted investigation and survey on 186 farm households in 2014 and carried out economic evaluation on "planting three to produce four" highyielding project of super hybrid rice. The results showed that the project of "planting three to produce four" performed significantly in terms of increasing yields and incomes. For example, per unit area yield of one-season late hybrid rice and middleseason hybrid rice proved the highest, and net income from middle-season rice in Longhui was the highest. It is obvious that to increase per unit yield is key for improving net incomes and to reduce machine fees and worker fees is crucial for decreasing fees.展开更多
Pig production efficiency and its regional differences in China have strategic importance to the transformation of pig production mode and optimization of pig production layout in China. In this paper,Malmquist-DEA mo...Pig production efficiency and its regional differences in China have strategic importance to the transformation of pig production mode and optimization of pig production layout in China. In this paper,Malmquist-DEA model is adopted to analyze the statistical data; TFP and its decomposition indicators of different pig breeding scale among the top ten pig producing provinces are calculated; both horizontal and longitudinal comparisons are made. Results show that among different pig breeding scales,free-range breeding scale is dominant in Hunan,small breeding scale is dominant in Sichuan,medium breeding scale is dominant in Sichuan and Hunan,and large breeding scale is dominant in Sichuan,Shandong and Jiangsu; among the provinces,pig production efficiency varies with breeding scale,and small-scale pig breeding in Sichuan,Guangdong and Hebei,free-range and medium-scale pig breeding in Hunan,medium-scale pig breeding in Henan and Yunnan,largescale pig breeding in the rest of the provinces,have significant efficiency advantage.展开更多
Basing on a viewpoint of all sided water producing system,a comprehensive analysis of the operation status and the relationship between each working unit in water producing system,including coagulation,sedimentation...Basing on a viewpoint of all sided water producing system,a comprehensive analysis of the operation status and the relationship between each working unit in water producing system,including coagulation,sedimentation and filtration etc.was made.By investigating the influence of backwashing consumption,the amount of sludge ejected from sedimentation tank and coagulant ratio upon the cost,the cost effective function of the system was presented.Afterwards,the solution was found out and the corresponding computer program was developed.When applied with real world data,it proved that this method significantly reduced the water producing cost.展开更多
基金supported by the National Key Research and Devel-opment Project of China(2021YFD1600101)the earmarked fund for the China Agriculture Research System(CARS-12,CARS-13 and CARS-14)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2024-OCRI).
文摘Flax(Linum usitatissimum L.)is an important oil crop in the high-altitude arid regions of China.Flaxseed is rich in various nutrients.However,the nutritional qualities of flaxseeds from different producing areas are still unclear.In this study,the nutritional characteristics of flaxseed from five producing areas in China were investigated.Twenty five nutritional quality indices in flaxseed were analyzed.Subsequently,chemometric methods,including cluster analysis,principal component analysis(PCA)and partial least square discriminant analysis(PLS-DA),were employed to discover the characteristics of nutritional qualities in flaxseeds.The results revealed there are significant differences in nutritional qualities among flaxseeds from different production areas.Six quality indices includingγ-tocopherol,vitamin E,phytosterols,oleic acid,α-linolenic acid,and cycloartenol were susceptible to producing area.In detail,the superiorcharacteristic nutrients of Ningxia flaxseed,Inner Mongolia flaxseed and Hebei flaxseed are vitamin E(17.3 mg/100g),α-linolenic acid(52.6%)and cycloartenol(1738.1 mg/kg),and phytosterols(3032.0 mg/kg),respectively.This study promotes the high-value development and utilization of local flaxseed industry.
基金Supported by the National Natural Science Foundation of China(42372165)Science and Technology Special Project of PetroChina Oil&Gas and New Energy Company(2023YQX10101)+1 种基金Project of the Ministry of Natural Resources of China(QGYQZYPJ2022-1)China National Petroleum Corporation Science and Technology Project(2024DJ93)。
文摘In the late 1970s,the theory of coal-formed gas began to take root,sprout,develop,and improve in China.After decades of development,a complete theoretical system was finally formed.The theory of coal-formed gas points out that coal measures are good gas source rocks,with gas as the main hydrocarbon generated and oil as the auxiliary.It has opened up a new exploration idea using coal-bearing humic organic matter as the gas source,transforming the theoretical guidance for natural gas exploration in China from“monism”(i.e.oil-type gas)to“dualism”(i.e.coal-formed gas and oil-type gas)and uncovering a new field of natural gas exploration.Before the establishment of the coal-formed gas theory,China was a gas-poor country with low proved gas initially-in-place(merely 2264.33×10^(8)m^(3))and production(137.3×10^(8)m^(3)/a),corresponding to a per capita annual consumption of only 14.37 m^(3).Guided by the theory of coal-formed gas,the natural gas industry of China has developed rapidly.By the end of 2023,China registered the cumulative proved gas initially-in-place of 20.90×10^(12)m^(3),an annual gas production of 2343×10^(8)m^(3),and a per capita domestic gas consumption reaching 167.36 m^(3).The cumulative proved reserves initially-in-place and production of natural gas were dominated by coal-formed gas.Owing to this advancement,China has transformed from a gas-poor country to the fourth largest gas producer in the world.The coal-formed gas theory and the tremendous achievements made in natural gas exploration in China under its guidance have promoted China from a gas-poor country to a major gas-producing country in the world.
基金Under the auspices of National Natural Science Foundation of China(No.42371181)。
文摘Promoting the deep integration of advanced manufacturing and producer services is not only a key path for metropolitan to climb the global value chain,but also an important new driving force for optimizing urban spatial structure.Based on the two dimen-sions of industrial linkage and spatial co-agglomeration from the perspective of industrial integration,taking Beijing,China as a case,using industrial input-output data,micro-enterprise spatial data,and methods such as industrial linkage model,standard deviation el-lipse,and spatial similarity coefficient,this study explores the coupling relationship between industrial linkage and spatial co-agglomer-ation of advanced manufacturing and producer services from 2007 to 2020.The results demonstrate that:1)the industrial linkage between advanced manufacturing and producer services in Beijing has an upward trend,in which the business services have the most significant improvement,in which the business services have the most improvement while the technology services have the most de-crease,but in general,the industrial linkage between the two industries shows a low level.2)Producer services were more spatially clustered than advanced manufacturing,and the degree of spatial co-agglomeration of the two also showed an increasing trend,with strong regional and industrial heterogeneity characteristics,among which the pairing industry involving commerce services and techno-logy services had a more obvious improvement.3)The coupling analysis found that the spatial dependence between advanced manufac-turing and producer services decreased,showing a weak positive correlation and a decreasing trend between industrial linkage and spa-tial co-agglomeration;the heterogeneity among subdivision pairs is prominent,and the strong correlation between industries does not mean that there is an inevitable spatial co-agglomeration.4)Based on the differences in coupling relationships and influence mechan-isms,four coupling modes are identified:H-H type,H-L type,L-L type,and L-H type.Finally,this study proposes three policy implica-tions for the integration of advanced manufacturing and producer services in metropolitan areas.
基金supported by grants managed by l’Agence Nationale de la Recherche under the Investissements d’Avenir programs Grant Nos. ANR-18-EURE-0014, ANR-10-LABX-0039-PALM, and ANR-22-CE30-0044supported by grants from Japan Society for the Promotion of Science (JSPS) KAKENHI (Grant No. 23K20038)+2 种基金JSPS Core-to-Core program (Grant No. JPJSCCA20230003)carried out within the framework of the EUROfusion Consortium, funded by the European Union via the Euratom Research and Training Programme (Grant Agreement No. 101052200-EUROfusion)operated within the framework of the Enabling Research Project No. AWP24-ENR-IFE.02.CEA-01 “Magnetized ICF”
文摘We report the observation of Zeeman splitting in multiple spectral lines emitted by a laser-produced,magnetized plasma(1–3×10^(18)cm^(-3),1–15 eV)in the context of a laboratory astrophysics experiment under a controlled magneticfield up to 20T.Nitrogen lines(NII)in the visible range were used to diagnose the magneticfield and plasma conditions.This was performed by coupling our data with(563–574 nm)the Stark–Zeeman line-shape code PPPB.The excellent agreement between experiment and simulations paves the way for a non-intrusive experimental platform to get time-resolved measurements of the local magneticfield in laboratory plasmas.
基金funded by the National Natural Science Foundation of China (41130748, 41101162)the Key Knowledge Innovation Project of Chinese Academy of Sciences (KZCX2-EW-304)
文摘A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors (e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance). In this study, an interval-probabilistic agricultural production structure optimization model (IPAPSOM) is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying (or risk of violating) system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty.
基金Supported by Project of Baotou University(BSY2010-23)~~
文摘[Objective] The paper was to establish embryonic stem cell system of goats. [Method] Numerous primordial germ cell colonies were derived from gonadal ridge and the surrounding tissues in 20 millimeter fetuses of down producing goat. Primordial germ cells and goats embryonic fibroblasts obtained from conceptus of equivaient gestational age were co-cultured. [Result] The colonies showed some characteristics of embryonic stem cells, such as the morphology of nest-like, they continued to be AKP positive and the ability to be continuously passed [Conclusion] These cells were pluripotent and ES-like cells.
基金supported by Chinese Academy of Science through the Knowledge Innovation Project of The Chinese Academy of Sciences (06LYQY3001)Funding for this project was also provided by Daqing Oilfield Co. Ltd., China
文摘The microbial community structure and functionally distinct groups in three kinds of produced water samples from the shallow,mesothermic and low-salinity Daqing oil reservoir were systematically evaluated using both culture-dependent and culture-independent methods.Sequence analysis of the 16S rRNA genes indicated that the bacterial library was dominated by Acinetobacter and Arcobacter and the archaeal community was dominated by Methanosaeta and Methanolinea.Two isolated methanogens were closely related with Methanothermobacter thermautotrophicus and Methanoculleus receptaculi.The fermentative bacteria were identified as Pseudomonas,Haloanaerobium,Alcalibacter,Arcobacter,and Pannonibacter.The predominant nitrate-reducing bacteria fell within the genus Pseudomonas.The dominant members of the cultured hydrocarbon-oxidizing bacteria were phylogenetically associated with Micrococcus,Pseudomonas,and Bacillus.Enrichments of biosurfactants and biopolymer producing groups mainly yielded Pseudomonas,Bacillus,and Acenitobacter-related members.The functional groups related to polymer degradation were also affiliated with Pseudomonas and Bacillus.Results from this study provide the fresh insight into the diversity of microbial communities in Daqing petroleum reservoirs.The vast pool of functional strains retrieved in this study was presumed to include the promising strains that could be applied in microbial-enhanced oil recovery in future.
文摘Based on the data from 1998 to 2005,area rainfall,flow of main hydrologic stations in Duhe River and upstream water level of the dam of Huanglongtan Reservoir in the lower reaches of Duhe River were analyzed,and the standard of flood-producing rainstorm in Duhe River was given,while temporal and spatial distribution and circulation flow situation characteristic of flood-producing rainstorm in Duhe River were studied.The results showed that the flood-producing rainstorm in Duhe River was mainly continuous intensive precipitation with the characteristic of long duration.There was most rainfall in Zhuxiquan River,Zhushanguandu River and southwest part of the middle and upper reaches of Duhe River,and next came Zhuxi River.Flood-producing rainstorm occurred in Duhe River with some favorable circulation features.For example,it was more favorable in the west Pacific subtropical high,and the convergence zone at northeast-southwest direction was formed between subtropical high and continental high pressure at 700 hPa,while southwest vortex moved eastward.Low pressure system at 850 hPa in south part of plateau developed and moved eastward to Chongqing region and formed low vortex or shear near Duhe River basin.Moreover,the characteristics of physical quantity field were analyzed,the results showed that temperature in plateau area and the south area of Duhe River basin increased obviously before rainstorm,and east pathway was the main path of cold air which affected flood-producing rainstorm in Duhe River.There was a θse intensive belt with NEE-SWW direction at 30°-40° N at 925-500 hPa,and moisture convergence was beneficial to the occurrence of rainstorm in Duhe River.
基金National Nonprofit Institute Research Grant (Graduate School of Chinese Academy of Agricultural Sciences,2009)
文摘This article conducts empirical analysis of rice growers' behavior of productive capital input and the influencing factors,using the input-output survey data concerning rice growing by 305 peasant households in 2009 in Huanan County and Huachuan County,Jiamusi City,Heilongjiang Province.I use Logit model to carry out econometric test of factors influencing the possibility of fixed productive investment.The test results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level,peasant households' expectation of the minimum purchase price of rice,have significant effect on whether to conduct fixed productive investment,whether there are disasters has no significant effect on the scale of peasant households' productive investment.Then I use Tobit model to carry out econometric test of factors influencing the scale of productive capital input.The results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level and family housing value,peasant households' expectation of the minimum purchase price of rice,whether there are disasters,have significant effect on the scale of peasant households' productive investment.On the basis of model test results,in order to promote the rice growers to increase fixed productive input and increase productive capital input,rational recommendations are put forward as follows:raising the minimum purchase price of rice,scaling up rice growing,making every effort to promote the educational level of rice growers,ensuring that the rice growers obtain productive capital input loans timely.
文摘A strain of hydrogen producing bacteria was immobilized by polyvinyl alcohol-boric acid method, with the addition of a small amount of calcium alginate. The immobilized cells were insensitive to the presence of traces of O2. Moreover, the immobilized cells increased both the evolution rate and the yield of hydrogen production. Batch experiments with a medium containing 10 g/L glucose demonstrated the yields of hydrogen production by the immobilized and free cells were 2.14 mol/mol glucose and 1.69 mol/mol glucose, respectively. In continuous cultures at medium retention time of 2.0 h, the yield and the evolution rate of hydrogen production by the immobilized cells were 2.31 mol/mol glucose and 1 435.4 ml/(L·h) respectively. However, at medium retention time of 6.0 h, the yield and the evolution rate of hydrogen production by free cells were only 1.75 mol/mol glucose and 362.9 ml/(L·h), respectively.
文摘The virulent factors of Escherichia coil (E.cofi) play an important role in the process of pathopoiesis. The study aimed to compare drug-resistant genes and virulence genes between extended spectrum β-1actamases (ESBLs)-producing E.coli and non-ESBLs-producing E.cofi to provide a reference for physicians in management of hospital infection. From October 2010 to August 2011,96 drug-resistant strains of E. coli isolated were collected from the specimens in Qingdao Municipal Hospital, Qingdao, China. These bacteria strains were divided into a ESBLs-producing group and a non-ESBLs-producing group. Drug sensitivity tests were performed using the Kirby-Bauer (K-B) method. Disinfectant gene, qacEAl-sull and 8 virulence genes (CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1) were tested by polymerase chain reaction (PCR). Among the 96 E.coli isolates, the ESBLs-producing E.coli comprised 46 (47.9%) strains and the non-ESBLs-producing E.cofi consisted of 50 (52.1%) strains. The detection rates of multiple drug-resistant strain, qacEAl-sull, CNF2, hlyA, eaeA,VT1, est, bfpA, elt, and CNF1 in 46 ESBLs-producing E.coli isolates were 89.1%, 76.1%, 6.5%, 69.6%, 69.6%, 89.1%, 10.9%, 26.1%, 8.7%, and 19.6%, respectively. In the non-ESBLs-producing E.cofi strains, the positive rates of multiple drug-resistant strain, qacEAl-sull, CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1 were 62.0%, 80.0%, 16.0%, 28.0%, 64.0%, 38.0%, 6.0%, 34.0%, 10.0%, and 24.0%, respectively. The difference in the detection rates of multiple drug-resistant strain, hlyA and VT1 between the ESBLs-producing E.cofi strains and the non-ESBLs-producing E.cofi strains was statistically significant (P〈0.05). The positive rate of multiple drug-resistant strains is higher in the ESBLs-producing strains than in the non-ESBLs-producing strains. The expression of some virulence genes hlyA and VT1 varies between the ESBLs-producing strains and the non-ESBLs-producing strains. Increased awareness of clinicians and enhanced testing by laboratories are required to reduce treatment failures and prevent the spread of multiple drug-resistant strains.
基金Supported by the Innovation Fund Project for Graduate Student of Xihua University
文摘On the basis of defining the producers in the supply chain of agricultural products,the SWOT analysis is adopted to analyze the advantages,disadvantages,opportunities and threats of producers in the supply chain of Chinese agricultural products.The paper analyzes the advantages of producers in the supply chain of agricultural products from three aspects including land resources,technology level of producers and input costs.The disadvantages of producers in the supply chain of agricultural products are analyzed from three aspects including scale level,mechanization and technology level and profit level.The opportunities of producers in the supply chain of agricultural products are analyzed from the aspects of laws,policies,capitals and technologies.The threats confronted by the producers in the supply chain of agricultural products are analyzed from foreign producers,negotiation control of supply chain of agricultural chain,environment protection and quality safety standard.On the basis of the analysis,the relevant suggestions on facilitating the interests of producers in the supply chain of Chinese agricultural products are put forward,including fully displaying the advantages of land resources;improving the knowledge and technology level of supply chain of agricultural production;establishing the alliances of producers of agricultural products to expand production scale;improving the quality of agricultural products to satisfy the relevant safety quality standard and environmental protection standard.
文摘The research conducted investigation and survey on 186 farm households in 2014 and carried out economic evaluation on "planting three to produce four" highyielding project of super hybrid rice. The results showed that the project of "planting three to produce four" performed significantly in terms of increasing yields and incomes. For example, per unit area yield of one-season late hybrid rice and middleseason hybrid rice proved the highest, and net income from middle-season rice in Longhui was the highest. It is obvious that to increase per unit yield is key for improving net incomes and to reduce machine fees and worker fees is crucial for decreasing fees.
基金Supported by Pig Innovation Team Project of Shandong Provincial Modern Agricultural Technology System(SDAIT-06-022-10)
文摘Pig production efficiency and its regional differences in China have strategic importance to the transformation of pig production mode and optimization of pig production layout in China. In this paper,Malmquist-DEA model is adopted to analyze the statistical data; TFP and its decomposition indicators of different pig breeding scale among the top ten pig producing provinces are calculated; both horizontal and longitudinal comparisons are made. Results show that among different pig breeding scales,free-range breeding scale is dominant in Hunan,small breeding scale is dominant in Sichuan,medium breeding scale is dominant in Sichuan and Hunan,and large breeding scale is dominant in Sichuan,Shandong and Jiangsu; among the provinces,pig production efficiency varies with breeding scale,and small-scale pig breeding in Sichuan,Guangdong and Hebei,free-range and medium-scale pig breeding in Hunan,medium-scale pig breeding in Henan and Yunnan,largescale pig breeding in the rest of the provinces,have significant efficiency advantage.
文摘Basing on a viewpoint of all sided water producing system,a comprehensive analysis of the operation status and the relationship between each working unit in water producing system,including coagulation,sedimentation and filtration etc.was made.By investigating the influence of backwashing consumption,the amount of sludge ejected from sedimentation tank and coagulant ratio upon the cost,the cost effective function of the system was presented.Afterwards,the solution was found out and the corresponding computer program was developed.When applied with real world data,it proved that this method significantly reduced the water producing cost.