The low efficiency and high cost of fresh agricultural product terminal distribution directly restrict the operation of the entire supply network.To reduce costs and optimize the distribution network,we construct a mi...The low efficiency and high cost of fresh agricultural product terminal distribution directly restrict the operation of the entire supply network.To reduce costs and optimize the distribution network,we construct a mixed integer programmingmodel that comprehensively considers tominimize fixed,transportation,fresh-keeping,time,carbon emissions,and performance incentive costs.We analyzed the performance of traditional rider distribution and robot distribution modes in detail.In addition,the uncertainty of the actual market demand poses a huge threat to the stability of the terminal distribution network.In order to resist uncertain interference,we further extend the model to a robust counterpart form.The results of the simulation show that the instability of random parameters will lead to an increase in the cost.Compared with the traditional rider distribution mode,the robot distribution mode can save 12.7%on logistics costs,and the distribution efficiency is higher.Our research can provide support for the design of planning schemes for transportation enterprise managers.展开更多
The cap-and-offset regulation is a practical scheme to lessen carbon emissions.The retailer selling fresh products can adopt sustainable technologies to lessen greenhouse gas emissions.We aim to analyze the optimal jo...The cap-and-offset regulation is a practical scheme to lessen carbon emissions.The retailer selling fresh products can adopt sustainable technologies to lessen greenhouse gas emissions.We aim to analyze the optimal joint strategies on order quantity and sustainable technology investment when the retailer faces stochastic market demand and can only acquire the mean and variance of distribution information.We construct a distributionally robust optimization model and use the Karush-Kuhn-Tucker(KKT)conditions to solve the analytic formula of optimal solutions.By comparing the models with and without investing in sustainable technologies,we examine the effect of sustainable technologies on the operational management decisions of the retailer.Finally,some computational examples are applied to analyze the impact of critical factors on operational strategies,and some managerial insights are given based on the analysis results.展开更多
A ratiometric fluorescent probe for hypoxanthine(Hx)detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride(Co doped g-C_(3)N_(4)).In addition...A ratiometric fluorescent probe for hypoxanthine(Hx)detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride(Co doped g-C_(3)N_(4)).In addition to emitting strong fluorescence,the peroxidase activity of Co doped g-C_(3)N_(4)can catalyze the reaction of O-phenylenediamine and H_(2)O_(2)to produce diallyl phthalate which can emit yellow fluorescence at 570 nm.Through the decomposition of Hx by xanthine oxidase,Hx can be indirectly detected by the generating hydrogen peroxide based on the measurement of fluorescent ratio I(F_(570)/F_(370)).The linear range was 1.7-272.2 mg/kg(R^(2)=0.997),and the detection limit was 1.52 mg/kg(3σ/K,n=9).The established method was applied to Hx detection in bass,grass carp,and shrimp,and the data were verified by HPLC.The result shows that the established probe is sensitive,accurate,and reliable,and can be used for Hx detection in aquatic products.展开更多
China's e-commerce market scale of fresh agricultural products has reached 1000 billion yuan,and the prospect is bright.However,in the face of such problems as quality control,storage and distribution,and consumpt...China's e-commerce market scale of fresh agricultural products has reached 1000 billion yuan,and the prospect is bright.However,in the face of such problems as quality control,storage and distribution,and consumption habits,the fresh product e-commerce has great difficulty in development.Internet generates large data,and data are the resources and the core of the Internet and the foundation for survival and development of Internet.This paper analyzed the current situation of the development of fresh agricultural products,and discussed the plight of fresh product e-commerce in scale,profit,non-standard,and network environment.On the basis of the whole industry supply chain,it came up with paths for upgrade and transformation of the fresh product e-commerce with the big data as the core in the context of Internet environment.展开更多
Link-up between farmers and supermarket is a new move adopted actively by the current government, conducive to consumers, farmers and circulation enterprises. At present, link-up between farmers and supermarket is lau...Link-up between farmers and supermarket is a new move adopted actively by the current government, conducive to consumers, farmers and circulation enterprises. At present, link-up between farmers and supermarket is launched in China's 15 provinces and cities, which will set off the revolution in the field of agricultural circulation. Based on the current situation of link-up between farmers and supermarket and the existing problems, we put forth the following recommendations: promoting the quality of farmers' cooperative organizations; establishing the logistics center of fresh agricultural products; using economies of scale to reduce the fresh logistics costs; improving the operation and management level of fresh agricultural products in supermarket.展开更多
In recent years,Guangxi realized consecutive bumper harvests in fresh agricultural products,leading increase of logistics demand;logistics infrastructure begins to take shape,and logistics of fresh agricultural produc...In recent years,Guangxi realized consecutive bumper harvests in fresh agricultural products,leading increase of logistics demand;logistics infrastructure begins to take shape,and logistics of fresh agricultural products takes on diversified development form with wholesale market as main form. However,traditional fresh agricultural products are not selling well and it lacks construction of supply chain; the construction of logistics information system for fresh agricultural products lags behind; organizational level of production and operation of fresh agricultural products is low. Through analyzing current situations and existing problems of logistics of Guangxi fresh agricultural products in the new period( 21 st century),this paper came up with recommendations for developing logistics of fresh agricultural products of Guangxi. Government should increase policy and financial support,build and manage supply chain of fresh agricultural products,accelerate construction of logistics information system for agricultural products,and improve organizational level of logistics of fresh agricultural products,to ensure healthy development of logistics of fresh agricultural products in Guangxi.展开更多
Submarine groundwater discharge(SGD)is being increasingly recognized as a significant source of nutrient into coastal waters,and generally comprises two components:submarine fresh groundwater discharge(SFGD)and recirc...Submarine groundwater discharge(SGD)is being increasingly recognized as a significant source of nutrient into coastal waters,and generally comprises two components:submarine fresh groundwater discharge(SFGD)and recirculated saline groundwater discharge(RSGD).The separate evaluation of SFGD and RSGD is extremely limited as compared to the conventional estimation of total SGD and associated nutrient fluxes,especially in marginal-scale regions.In this study,new high-resolution radium isotopes data in seawater and coastal groundwater enabled an estimation of SGD flux in a typical marginal sea of the Yellow Sea.By establishing 226Ra and 228Ra mass balance models,we obtained the SGD-derived radium fluxes,and then estimated the SFGD and RSGD fluxes through a two end-member model.The results showed that the total SGD flux into the Yellow Sea was equivalent to approximately 6.6 times the total freshwater discharge of surrounding rivers,and the SFGD flux accounted for only 5.2%–8.8%of the total SGD.Considering the nutrient concentrations in coastal fresh and saline groundwater,we obtained the dissolved inorganic nutrient fluxes(mmol m^(-2) yr^(-1))to be 52–353 for nitrogen(DIN),0.21–1.4 for phosphorus(DIP),34–226 for silicon(DSi)via SFGD,and 69–262 for DIN,1.0–3.9 for DIP,70–368 for DSi via RSGD,with the sum of nutrient fluxes equaling to(1.8–9.3)-fold,(1.3–5.6)-fold and(2.0–9.5)-fold of the riverine inputs.Compared to the conventional estimation of the total SGD flux,the nutrient fluxes derived from the separation of SFGD and RSGD were(1.6–2.1),(1.6–1.8)and(4.0–4.9)times lower for DIN,DIP and DSi,respectively,indicating that the estimates by separating SFGD and RSGD could be conservative and representative results of the Yellow Sea.Furthermore,we suggested that SGD played an important role in nutrient sources among all the traditional nutrient inputs sources,providing 15%–48%,33%–68%and 14%–43%of the total DIN,DIP and DSi input fluxes into the Yellow Sea,and the high nutrient stoichiometric ratios(i.e.,DIN/DIP)in SGD probably contributed to the increasing ratios in the Yellow Sea.In addition delivering large amounts of nutrient into the Yellow Sea,SGD would create primary productivity of 10–49,1.6–6.8 and 8.8–42 g C m^(-2)yr^(-1) based on N,P and Si,which were equivalent to 5.2%–27%,0.9%–3.7%and 4.7%–23%of the total primary productivity,respectively.In particular,the SFGD-derived DIN flux can be converted to primary productivity of 4.2–28 g C m^(-2)yr^(-1) thus demonstrating the disproportionately large role of SFGD in ecological environment of the Yellow Sea relative to its flux.Therefore,we conclude that SGD,particularly SFGD,plays an important role as a nutrient source for the Yellow Sea,and not only affects nutrient budgets and structures but also enhances the primary productivity.展开更多
In view of the uncertainty in the location selection of logistics distribution center for the fresh agricultural products,the present study established a robust model based on the maximization of principal component s...In view of the uncertainty in the location selection of logistics distribution center for the fresh agricultural products,the present study established a robust model based on the maximization of principal component score taking budget cost parameters as an example.In the process of model solving,the interval form of the uncertain set was used to clarify the constraint conditions,to transform into a certain 0-1 integer linear programming model,so as to solve with the aid of LINGO software.Finally,through studying the location selection of logistics distribution center for fresh agricultural products in the Beijing-Tianjin-Hebei region,it analyzed the application of the robust model and tested the validity of the model.展开更多
In this study,we established a comprehensive method for simultaneous identification and quantification of tetrodotoxin(TTX) in fresh pufferfish tissues and pufferfish-based products using liquid chromatography/quadrup...In this study,we established a comprehensive method for simultaneous identification and quantification of tetrodotoxin(TTX) in fresh pufferfish tissues and pufferfish-based products using liquid chromatography/quadrupole-linear ion trap mass spectrometry(LC-QqLIT-MS).TTX was extracted by 1% acetic acid-methanol,and most of the lipids were then removed by freezing lipid precipitation,followed by purification and concentration using irnmunoaffinity columns(IACs).Matrix effects were substantially reduced due to the high specificity of the IACs,and thus,background interference was avoided.Quantitation analysis was therefore performed using an external calibration curve with standards prepared in mobile phase.The method was evaluated by fortifying samples at 1,10,and 100 ng/g,respectively,and the recoveries ranged from 75.8%-107%,with a relative standard deviation of less than 15%.The TTX calibration curves were linear over the range of 1-1 000 ng/L,with a detection limit of 0.3 ng/g and a quantification limit of 1 ng/g.Using this method,samples can be further analyzed using an informationdependent acquisition(IDA) experiment,in the positive mode,from a single liquid chromatography-tandem mass spectrometry injection,which can provide an extra level of confirmation by matching the full product ion spectra acquired for a standard sample with those from an enhanced product ion(EPI) library.The scheduled multiple reaction monitoring method enabled TTX to be screened for,and TTX was positively identified using the IDA and EPI spectra.This method was successfully applied to analyze a total of 206 samples of fresh pufferfish tissues and pufferfish-based products.The results from this study show that the proposed method can be used to quantify and identify TTX in a single run with excellent sensitivity and reproducibility,and is suitable for the analysis of complex matrix pufferfish samples.展开更多
This paper firstly introduced the two stage supply chain consisting of single agricultural product producer and fund restraint retailer.Then,it analyzed the influence of bank interest rate on order quantity,wholesale ...This paper firstly introduced the two stage supply chain consisting of single agricultural product producer and fund restraint retailer.Then,it analyzed the influence of bank interest rate on order quantity,wholesale price and expected profit of retailer and producer on the condition of retailer taking external loan strategy.Studies have shown that when the bank interest rate is in(0,0.9),the order quantity of agricultural products is a decreasing function of bank interest rate; when the bank interest rate is in(0,1),wholesale price of agricultural products decreases with increase in the bank interest rate; when the bank interest rate is in(0,0.6),the expected profit of retailer is a decreasing function of bank interest rate; when the bank interest rate is in(0,1),the expected profit of producer decreases with increase in the bank interest rate.Finally,through simulation calculation examples,it verified suitability of the conclusion,in the hope of providing reference and application value for management of supply chain.展开更多
The paper introduced the connotation of network marketing of fresh agricultural products and analyzed the fundaments of launching the C2C marketing of fresh agricultural products in China.The fundaments mainly cover t...The paper introduced the connotation of network marketing of fresh agricultural products and analyzed the fundaments of launching the C2C marketing of fresh agricultural products in China.The fundaments mainly cover the development of e-commerce,the transformation of consumption concept,the change of life style and the features of Chinese agricultural production.The developmental status of the C2C marketing of Chinese fresh vegetables and fresh fruits is introduced and the plights,including imperfect rural network infrastructure,inadequate talents specialized in network marketing of fresh agricultural products,uneven quality of agricultural products,immature logistics system,uncertainty existed in faced by the C2C marketing of fresh agricultural products and imperfect governmental protection system,are pointed out.In the end,the developmental trend of Chinese network marketing of fresh agricultural products on the basis of C2C mode is described.展开更多
This paper firstly introduced the PHP + Oracle database development technology. Based on B / S structure,using MVC( Model View Controller) framework development mode,and in line with actual demands of fresh agricultur...This paper firstly introduced the PHP + Oracle database development technology. Based on B / S structure,using MVC( Model View Controller) framework development mode,and in line with actual demands of fresh agricultural products for e-marketing in Shanghai,it designed and expected to realize e-marketing system for fresh agricultural products in B2B2 C mode. It made an in-depth analysis from system demands,design of functional modules,design of database,and relevant technologies for system realization.展开更多
[Objectives]To compare anti-inflammatory and analgesic effects of fresh and dry products of Zhuang medicine Asystaia gangetica on mice.[Methods]Experiments were performed using glacial acetic acid to increase capillar...[Objectives]To compare anti-inflammatory and analgesic effects of fresh and dry products of Zhuang medicine Asystaia gangetica on mice.[Methods]Experiments were performed using glacial acetic acid to increase capillary permeability in mice,cotton ball to cause granulomatous formation in mice,xylene to cause auricular swelling in mice,chronic inflammation,and acetic acid-induced pain and hot-plate pain.Besides,the anti-inflammatory and analgesic effects of fresh and dry products of A.gangetica on mice were observed with the indicators of capillary permeability in the abdominal cavity,swelling rate of auricles,cotton ball granulomas and writhing times,and thermal pain threshold.[Results]Fresh products of A.gangetica had significant inhibitory effects on peritoneal capillary permeability increase in mice induced by glacial acetic acid,mouse auricle swelling induced by xylene,and mouse granuloma formation induced by cotton balls.Dry products of A.gangetica also significantly inhibited the auricle swelling in mice induced by xylene,but the effect intensity was weaker than that of fresh products.In addition,dry products of A.gangetica showed a certain tendency to inhibit the increase of capillary permeability in the abdominal cavity of mice induced by glacial acetic acid.In the analgesic experiment,both fresh and dry products of A.gangetica showed better analgesic effect,but caused pain on the hot plate,and the analgesic effect time of fresh products was shorter than that of dry products.[Conclusions]Both fresh and dry products of Zhuang medicine A.gangetica have certain anti-inflammatory and analgesic effects.展开更多
Through the initial selection,screening and simplification,a set of performance appraisal system of logistic distribution suited to fresh agricultural products is established.In the process of establishing the apprais...Through the initial selection,screening and simplification,a set of performance appraisal system of logistic distribution suited to fresh agricultural products is established.In the process of establishing the appraisal indicator,the representative appraisal indicator of logistic distribution of fresh agricultural products is further obtained by delivering experts' survey and applying the ABC screening system.The distribution costs,transportation and service level belong to the first level indicator;packing fees,distribution processing fees,full-load ratio,haulage capacity,customer satisfaction and the strain capability of delivery personnel belong to second level indicator.At the same time,the weighing of each indicator is determined.The quantification is conducted on indicators.The qualitative indicators applies ten-point system and then coverts these indicators into percentage,that is the number between [0,1];as for the quantitative indicators,they are concluded to the interval [0,1] according to the actual value range of the indicators and by applying the grade of membership in the vague mathematics.Through the analyses of the advantages and disadvantages of the frequently used performance evaluation method and its applicable conditions,the comprehensive evaluation of logistic distribution of agricultural products obtained by using the method of fuzzy comprehensive appraisal.The results show that,in terms of reducing distribution costs,the packaging and distribution processing technology of fresh agricultural products should be improved,so as to reduce distribution costs.In the process of introducing the application of advanced technology,the high automatic logistic equipments should be introduced.展开更多
In this paper, considering a scenario in which there are two quality levels of fresh products and introduction of consumer utility function, we studied the optimal ordering and pricing strategies under certain quantit...In this paper, considering a scenario in which there are two quality levels of fresh products and introduction of consumer utility function, we studied the optimal ordering and pricing strategies under certain quantity. Our results showed that, facing the two quality levels of fresh products, retailers would not benefit from sales of lower quality of fresh products with the deterministic demand. In the pursuit of profit maximization, the initial order quantity is smaller than the potential demand for market.展开更多
With the establishment of a well-off society in an all-round way,Chinese residents have put forward higher requirements for the quality and safety of fresh agricultural products.In recent years,domestic and foreign ac...With the establishment of a well-off society in an all-round way,Chinese residents have put forward higher requirements for the quality and safety of fresh agricultural products.In recent years,domestic and foreign academic circles have also paid more and more attention to the risk of fresh agricultural product supply chain.This article collects and sorts out the research findings of domestic and foreign scholars on the risk assessment of fresh agricultural product supply chain in recent years,and summarizes and discusses from three aspects:supply chain risk factors,risk assessment indicator selection,and risk assessment methods.It is intended to provide a reference for future new research ideas and research perspectives.展开更多
The paper mainly discusses the influence of chemical,physical and biological preservation technology improvement on the preservation strategy of fresh agricultural products.Meantime,the relationship between fresh agri...The paper mainly discusses the influence of chemical,physical and biological preservation technology improvement on the preservation strategy of fresh agricultural products.Meantime,the relationship between fresh agricultural products ordering and preservation in the environment of new normal carbon emission constraint is analyzed,and the e-commerce strategy in the digital era is put forward to achieve the win-win situation of consumers,farmers and dealers,so as to achieve good ecological,economic and social benefits.展开更多
When open a website specialized in selling fresh fruits and vegetables collecting from all over the world,you will see that there are diversity of the raw materials of highest quality like Peruvian tangerine,Argentine...When open a website specialized in selling fresh fruits and vegetables collecting from all over the world,you will see that there are diversity of the raw materials of highest quality like Peruvian tangerine,Argentine red shrimp,Australian steak,and so on.You can just sit in front of your computer and order online,and after several days you will receive those fresh foods from another country at home.展开更多
The supply chain finance(SCF)solutions are becoming increasingly diversified with the continuous perfection of the economic system.However,financing for small and medium sized enterprises(SMEs)is still a difficult iss...The supply chain finance(SCF)solutions are becoming increasingly diversified with the continuous perfection of the economic system.However,financing for small and medium sized enterprises(SMEs)is still a difficult issue waiting to be solved by enterprises and the government in China.SCF solutions based on e-commerce platforms have developed rapidly in China that provide an alternative for SMEs when few studies have been conducted on e-commerce SCF solutions which focus on fresh agricultural products.Therefore,this research focuses on the SCF solutions applicable to e-commerce enterprises of fresh agricultural products.展开更多
文摘The low efficiency and high cost of fresh agricultural product terminal distribution directly restrict the operation of the entire supply network.To reduce costs and optimize the distribution network,we construct a mixed integer programmingmodel that comprehensively considers tominimize fixed,transportation,fresh-keeping,time,carbon emissions,and performance incentive costs.We analyzed the performance of traditional rider distribution and robot distribution modes in detail.In addition,the uncertainty of the actual market demand poses a huge threat to the stability of the terminal distribution network.In order to resist uncertain interference,we further extend the model to a robust counterpart form.The results of the simulation show that the instability of random parameters will lead to an increase in the cost.Compared with the traditional rider distribution mode,the robot distribution mode can save 12.7%on logistics costs,and the distribution efficiency is higher.Our research can provide support for the design of planning schemes for transportation enterprise managers.
基金supported by the National Natural Science Foundation of China (Grant No.71702087)the Youth Innovation Science and Technology Support Program of Shandong Province Higher Education (Grant No.2021RW024)the Special Funds for Taishan Scholars,Shandong (Grant No.tsqn202103063).
文摘The cap-and-offset regulation is a practical scheme to lessen carbon emissions.The retailer selling fresh products can adopt sustainable technologies to lessen greenhouse gas emissions.We aim to analyze the optimal joint strategies on order quantity and sustainable technology investment when the retailer faces stochastic market demand and can only acquire the mean and variance of distribution information.We construct a distributionally robust optimization model and use the Karush-Kuhn-Tucker(KKT)conditions to solve the analytic formula of optimal solutions.By comparing the models with and without investing in sustainable technologies,we examine the effect of sustainable technologies on the operational management decisions of the retailer.Finally,some computational examples are applied to analyze the impact of critical factors on operational strategies,and some managerial insights are given based on the analysis results.
基金supported by the National Natural Science Foundation of China(21804050)the National Key R and D Program of China(2018YFD0901003)+2 种基金the Science and Technology Planning Project of Xiamen,China(3502Z20183031)the Fujian Provincial Fund Project(2018J01432)the Xiamen Science and Technology Planning Project,China(3502Z20183031)。
文摘A ratiometric fluorescent probe for hypoxanthine(Hx)detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride(Co doped g-C_(3)N_(4)).In addition to emitting strong fluorescence,the peroxidase activity of Co doped g-C_(3)N_(4)can catalyze the reaction of O-phenylenediamine and H_(2)O_(2)to produce diallyl phthalate which can emit yellow fluorescence at 570 nm.Through the decomposition of Hx by xanthine oxidase,Hx can be indirectly detected by the generating hydrogen peroxide based on the measurement of fluorescent ratio I(F_(570)/F_(370)).The linear range was 1.7-272.2 mg/kg(R^(2)=0.997),and the detection limit was 1.52 mg/kg(3σ/K,n=9).The established method was applied to Hx detection in bass,grass carp,and shrimp,and the data were verified by HPLC.The result shows that the established probe is sensitive,accurate,and reliable,and can be used for Hx detection in aquatic products.
基金Supported by Social Science Research Common Program of Beijing Municipal Commission of Education 2017 "Study on E-commerce Logistics Model of Fresh Agricultural Products Based on Big Data"(SY201712448002)
文摘China's e-commerce market scale of fresh agricultural products has reached 1000 billion yuan,and the prospect is bright.However,in the face of such problems as quality control,storage and distribution,and consumption habits,the fresh product e-commerce has great difficulty in development.Internet generates large data,and data are the resources and the core of the Internet and the foundation for survival and development of Internet.This paper analyzed the current situation of the development of fresh agricultural products,and discussed the plight of fresh product e-commerce in scale,profit,non-standard,and network environment.On the basis of the whole industry supply chain,it came up with paths for upgrade and transformation of the fresh product e-commerce with the big data as the core in the context of Internet environment.
基金Supported by Humanities and Social Sciences Youth Project of theMinistry of Education in 2010 (10YJC790234)
文摘Link-up between farmers and supermarket is a new move adopted actively by the current government, conducive to consumers, farmers and circulation enterprises. At present, link-up between farmers and supermarket is launched in China's 15 provinces and cities, which will set off the revolution in the field of agricultural circulation. Based on the current situation of link-up between farmers and supermarket and the existing problems, we put forth the following recommendations: promoting the quality of farmers' cooperative organizations; establishing the logistics center of fresh agricultural products; using economies of scale to reduce the fresh logistics costs; improving the operation and management level of fresh agricultural products in supermarket.
基金Supported by Research Project for Logistics System of Characteristic Agricultural Products of Nanning City(2012ZD04)
文摘In recent years,Guangxi realized consecutive bumper harvests in fresh agricultural products,leading increase of logistics demand;logistics infrastructure begins to take shape,and logistics of fresh agricultural products takes on diversified development form with wholesale market as main form. However,traditional fresh agricultural products are not selling well and it lacks construction of supply chain; the construction of logistics information system for fresh agricultural products lags behind; organizational level of production and operation of fresh agricultural products is low. Through analyzing current situations and existing problems of logistics of Guangxi fresh agricultural products in the new period( 21 st century),this paper came up with recommendations for developing logistics of fresh agricultural products of Guangxi. Government should increase policy and financial support,build and manage supply chain of fresh agricultural products,accelerate construction of logistics information system for agricultural products,and improve organizational level of logistics of fresh agricultural products,to ensure healthy development of logistics of fresh agricultural products in Guangxi.
基金This research was supported by the National Natural Science Foundation of China(Grants Nos.41376089,41576083,41976040)the National Science and Technology Major Project of the Ministry of Science and Technology of China(2016YFC1402106)China Postdoctoral Science Foundation(2020M671048)。
文摘Submarine groundwater discharge(SGD)is being increasingly recognized as a significant source of nutrient into coastal waters,and generally comprises two components:submarine fresh groundwater discharge(SFGD)and recirculated saline groundwater discharge(RSGD).The separate evaluation of SFGD and RSGD is extremely limited as compared to the conventional estimation of total SGD and associated nutrient fluxes,especially in marginal-scale regions.In this study,new high-resolution radium isotopes data in seawater and coastal groundwater enabled an estimation of SGD flux in a typical marginal sea of the Yellow Sea.By establishing 226Ra and 228Ra mass balance models,we obtained the SGD-derived radium fluxes,and then estimated the SFGD and RSGD fluxes through a two end-member model.The results showed that the total SGD flux into the Yellow Sea was equivalent to approximately 6.6 times the total freshwater discharge of surrounding rivers,and the SFGD flux accounted for only 5.2%–8.8%of the total SGD.Considering the nutrient concentrations in coastal fresh and saline groundwater,we obtained the dissolved inorganic nutrient fluxes(mmol m^(-2) yr^(-1))to be 52–353 for nitrogen(DIN),0.21–1.4 for phosphorus(DIP),34–226 for silicon(DSi)via SFGD,and 69–262 for DIN,1.0–3.9 for DIP,70–368 for DSi via RSGD,with the sum of nutrient fluxes equaling to(1.8–9.3)-fold,(1.3–5.6)-fold and(2.0–9.5)-fold of the riverine inputs.Compared to the conventional estimation of the total SGD flux,the nutrient fluxes derived from the separation of SFGD and RSGD were(1.6–2.1),(1.6–1.8)and(4.0–4.9)times lower for DIN,DIP and DSi,respectively,indicating that the estimates by separating SFGD and RSGD could be conservative and representative results of the Yellow Sea.Furthermore,we suggested that SGD played an important role in nutrient sources among all the traditional nutrient inputs sources,providing 15%–48%,33%–68%and 14%–43%of the total DIN,DIP and DSi input fluxes into the Yellow Sea,and the high nutrient stoichiometric ratios(i.e.,DIN/DIP)in SGD probably contributed to the increasing ratios in the Yellow Sea.In addition delivering large amounts of nutrient into the Yellow Sea,SGD would create primary productivity of 10–49,1.6–6.8 and 8.8–42 g C m^(-2)yr^(-1) based on N,P and Si,which were equivalent to 5.2%–27%,0.9%–3.7%and 4.7%–23%of the total primary productivity,respectively.In particular,the SFGD-derived DIN flux can be converted to primary productivity of 4.2–28 g C m^(-2)yr^(-1) thus demonstrating the disproportionately large role of SFGD in ecological environment of the Yellow Sea relative to its flux.Therefore,we conclude that SGD,particularly SFGD,plays an important role as a nutrient source for the Yellow Sea,and not only affects nutrient budgets and structures but also enhances the primary productivity.
基金Supported by Student Innovation and Entrepreneurship Training Program Project of Hebei Agricultural University(2020102).
文摘In view of the uncertainty in the location selection of logistics distribution center for the fresh agricultural products,the present study established a robust model based on the maximization of principal component score taking budget cost parameters as an example.In the process of model solving,the interval form of the uncertain set was used to clarify the constraint conditions,to transform into a certain 0-1 integer linear programming model,so as to solve with the aid of LINGO software.Finally,through studying the location selection of logistics distribution center for fresh agricultural products in the Beijing-Tianjin-Hebei region,it analyzed the application of the robust model and tested the validity of the model.
基金Supported by the National Natural Science Foundation of China(No.41106109)the China National Food Safety Standards Development Project(No.ZHENGHE-2015-356)
文摘In this study,we established a comprehensive method for simultaneous identification and quantification of tetrodotoxin(TTX) in fresh pufferfish tissues and pufferfish-based products using liquid chromatography/quadrupole-linear ion trap mass spectrometry(LC-QqLIT-MS).TTX was extracted by 1% acetic acid-methanol,and most of the lipids were then removed by freezing lipid precipitation,followed by purification and concentration using irnmunoaffinity columns(IACs).Matrix effects were substantially reduced due to the high specificity of the IACs,and thus,background interference was avoided.Quantitation analysis was therefore performed using an external calibration curve with standards prepared in mobile phase.The method was evaluated by fortifying samples at 1,10,and 100 ng/g,respectively,and the recoveries ranged from 75.8%-107%,with a relative standard deviation of less than 15%.The TTX calibration curves were linear over the range of 1-1 000 ng/L,with a detection limit of 0.3 ng/g and a quantification limit of 1 ng/g.Using this method,samples can be further analyzed using an informationdependent acquisition(IDA) experiment,in the positive mode,from a single liquid chromatography-tandem mass spectrometry injection,which can provide an extra level of confirmation by matching the full product ion spectra acquired for a standard sample with those from an enhanced product ion(EPI) library.The scheduled multiple reaction monitoring method enabled TTX to be screened for,and TTX was positively identified using the IDA and EPI spectra.This method was successfully applied to analyze a total of 206 samples of fresh pufferfish tissues and pufferfish-based products.The results from this study show that the proposed method can be used to quantify and identify TTX in a single run with excellent sensitivity and reproducibility,and is suitable for the analysis of complex matrix pufferfish samples.
基金Supported by Key Project of National Natural Science Foundation(70932005)Project of National Natural Science Foundation(71102055,71372140)Young Scholar Project of Sichuan Provincial Education Department(13ZB0035,14ZA0304)
文摘This paper firstly introduced the two stage supply chain consisting of single agricultural product producer and fund restraint retailer.Then,it analyzed the influence of bank interest rate on order quantity,wholesale price and expected profit of retailer and producer on the condition of retailer taking external loan strategy.Studies have shown that when the bank interest rate is in(0,0.9),the order quantity of agricultural products is a decreasing function of bank interest rate; when the bank interest rate is in(0,1),wholesale price of agricultural products decreases with increase in the bank interest rate; when the bank interest rate is in(0,0.6),the expected profit of retailer is a decreasing function of bank interest rate; when the bank interest rate is in(0,1),the expected profit of producer decreases with increase in the bank interest rate.Finally,through simulation calculation examples,it verified suitability of the conclusion,in the hope of providing reference and application value for management of supply chain.
文摘The paper introduced the connotation of network marketing of fresh agricultural products and analyzed the fundaments of launching the C2C marketing of fresh agricultural products in China.The fundaments mainly cover the development of e-commerce,the transformation of consumption concept,the change of life style and the features of Chinese agricultural production.The developmental status of the C2C marketing of Chinese fresh vegetables and fresh fruits is introduced and the plights,including imperfect rural network infrastructure,inadequate talents specialized in network marketing of fresh agricultural products,uneven quality of agricultural products,immature logistics system,uncertainty existed in faced by the C2C marketing of fresh agricultural products and imperfect governmental protection system,are pointed out.In the end,the developmental trend of Chinese network marketing of fresh agricultural products on the basis of C2C mode is described.
文摘This paper firstly introduced the PHP + Oracle database development technology. Based on B / S structure,using MVC( Model View Controller) framework development mode,and in line with actual demands of fresh agricultural products for e-marketing in Shanghai,it designed and expected to realize e-marketing system for fresh agricultural products in B2B2 C mode. It made an in-depth analysis from system demands,design of functional modules,design of database,and relevant technologies for system realization.
基金Talent Cultivation Construction Project of Professor Yang Shilin's Team of Guangxi University of Chinese Medicine(CS17015).
文摘[Objectives]To compare anti-inflammatory and analgesic effects of fresh and dry products of Zhuang medicine Asystaia gangetica on mice.[Methods]Experiments were performed using glacial acetic acid to increase capillary permeability in mice,cotton ball to cause granulomatous formation in mice,xylene to cause auricular swelling in mice,chronic inflammation,and acetic acid-induced pain and hot-plate pain.Besides,the anti-inflammatory and analgesic effects of fresh and dry products of A.gangetica on mice were observed with the indicators of capillary permeability in the abdominal cavity,swelling rate of auricles,cotton ball granulomas and writhing times,and thermal pain threshold.[Results]Fresh products of A.gangetica had significant inhibitory effects on peritoneal capillary permeability increase in mice induced by glacial acetic acid,mouse auricle swelling induced by xylene,and mouse granuloma formation induced by cotton balls.Dry products of A.gangetica also significantly inhibited the auricle swelling in mice induced by xylene,but the effect intensity was weaker than that of fresh products.In addition,dry products of A.gangetica showed a certain tendency to inhibit the increase of capillary permeability in the abdominal cavity of mice induced by glacial acetic acid.In the analgesic experiment,both fresh and dry products of A.gangetica showed better analgesic effect,but caused pain on the hot plate,and the analgesic effect time of fresh products was shorter than that of dry products.[Conclusions]Both fresh and dry products of Zhuang medicine A.gangetica have certain anti-inflammatory and analgesic effects.
文摘Through the initial selection,screening and simplification,a set of performance appraisal system of logistic distribution suited to fresh agricultural products is established.In the process of establishing the appraisal indicator,the representative appraisal indicator of logistic distribution of fresh agricultural products is further obtained by delivering experts' survey and applying the ABC screening system.The distribution costs,transportation and service level belong to the first level indicator;packing fees,distribution processing fees,full-load ratio,haulage capacity,customer satisfaction and the strain capability of delivery personnel belong to second level indicator.At the same time,the weighing of each indicator is determined.The quantification is conducted on indicators.The qualitative indicators applies ten-point system and then coverts these indicators into percentage,that is the number between [0,1];as for the quantitative indicators,they are concluded to the interval [0,1] according to the actual value range of the indicators and by applying the grade of membership in the vague mathematics.Through the analyses of the advantages and disadvantages of the frequently used performance evaluation method and its applicable conditions,the comprehensive evaluation of logistic distribution of agricultural products obtained by using the method of fuzzy comprehensive appraisal.The results show that,in terms of reducing distribution costs,the packaging and distribution processing technology of fresh agricultural products should be improved,so as to reduce distribution costs.In the process of introducing the application of advanced technology,the high automatic logistic equipments should be introduced.
文摘In this paper, considering a scenario in which there are two quality levels of fresh products and introduction of consumer utility function, we studied the optimal ordering and pricing strategies under certain quantity. Our results showed that, facing the two quality levels of fresh products, retailers would not benefit from sales of lower quality of fresh products with the deterministic demand. In the pursuit of profit maximization, the initial order quantity is smaller than the potential demand for market.
文摘With the establishment of a well-off society in an all-round way,Chinese residents have put forward higher requirements for the quality and safety of fresh agricultural products.In recent years,domestic and foreign academic circles have also paid more and more attention to the risk of fresh agricultural product supply chain.This article collects and sorts out the research findings of domestic and foreign scholars on the risk assessment of fresh agricultural product supply chain in recent years,and summarizes and discusses from three aspects:supply chain risk factors,risk assessment indicator selection,and risk assessment methods.It is intended to provide a reference for future new research ideas and research perspectives.
文摘The paper mainly discusses the influence of chemical,physical and biological preservation technology improvement on the preservation strategy of fresh agricultural products.Meantime,the relationship between fresh agricultural products ordering and preservation in the environment of new normal carbon emission constraint is analyzed,and the e-commerce strategy in the digital era is put forward to achieve the win-win situation of consumers,farmers and dealers,so as to achieve good ecological,economic and social benefits.
文摘When open a website specialized in selling fresh fruits and vegetables collecting from all over the world,you will see that there are diversity of the raw materials of highest quality like Peruvian tangerine,Argentine red shrimp,Australian steak,and so on.You can just sit in front of your computer and order online,and after several days you will receive those fresh foods from another country at home.
文摘The supply chain finance(SCF)solutions are becoming increasingly diversified with the continuous perfection of the economic system.However,financing for small and medium sized enterprises(SMEs)is still a difficult issue waiting to be solved by enterprises and the government in China.SCF solutions based on e-commerce platforms have developed rapidly in China that provide an alternative for SMEs when few studies have been conducted on e-commerce SCF solutions which focus on fresh agricultural products.Therefore,this research focuses on the SCF solutions applicable to e-commerce enterprises of fresh agricultural products.