Thermo-elastic analysis of simply-supported orthotropic laminated beams subjected to high temperature and mechanical load is presented on the basis of the exact two-dimensional thermoelasticity theory.The beam is comp...Thermo-elastic analysis of simply-supported orthotropic laminated beams subjected to high temperature and mechanical load is presented on the basis of the exact two-dimensional thermoelasticity theory.The beam is composed of several orthotropic layers,each with temperaturedependent material properties.The governing equation for each layer is analytically solved using the state space method.The displacement and stress solutions of the beam are obtained using the transfer-matrix method.A numerical example is included to study the effects of temperature on the mechanical responses of a sandwich beam.The results reveal two main effects of temperature:(i)inducing deformations and stresses by itself;(ii)affecting the deformations and stresses induced by the mechanical load.展开更多
Due to the lack of effective assessment method,overheated milk commodities are often marketed as pasteurized milk on the market,which was sold in high price by fraud.Thus,this article aims to establish an approach bas...Due to the lack of effective assessment method,overheated milk commodities are often marketed as pasteurized milk on the market,which was sold in high price by fraud.Thus,this article aims to establish an approach based on metabolomics to monitor thermal processing temperature of bovine milk.Metabolomics data of bovine milk samples heated at temperatures ranging from 60℃to 150℃were achieved by ultra-performance liquid chromatography-high-resolution mass spectrometry(UPLC-HRMS)platform,followed by multivariate data analysis.A regular variation pattern of chemical composition as temperature rises was pictured,furthermore.N^(∈)carboxymethyl lysine(CML),N^(∈)-carboxyethyl lysine(CEL),pentosidine.pvrraline and lysinoalanine(LAL)were identified as 5 of the most contributed compounds to discriminate pasteurized and ultra-high-temperature(UHT)milk.By the comprehensive study on their content changes,we concluded that the optimal temperature range was 90-100℃for the generation of CML and CEL in this experiment,moreover.110~120℃for LAL.S0~100℃for pentosidine and 130-140℃for pvrraline.Finally,a predicted rule to discriminate pasteurized and UHT milk was preliminarily established based on the ratios of CML/CEL.CEL/pentosidine and CML/pentosidine.which could be applied in food labelling authentication of commercial bovine milk after further validation.展开更多
We propose a fluid model driven by the queue length process of a working vacation queue with PH service distribution, which can be applied to the Ad Hoc network with every data group. We obtain the stationary distribu...We propose a fluid model driven by the queue length process of a working vacation queue with PH service distribution, which can be applied to the Ad Hoc network with every data group. We obtain the stationary distribution of the queue length in driving process based on a quasi-birth-and-death process. Then, we analyze the fluid model, and derive the differential equations satisfied by the stationary joint distribution of the fluid queue based on the balance equation. Moreover, we obtain some performance indices, such as, the average throughput, server utilization and the mean buffer content. These indices are relevant to pack transmission in the network, and they can be obtained by using the Laplace Transform (LT) and the Laplace-Stieltjes Transform (LST). Finally, some numerical examples have been discussed with respect to the effect of several parameters on the system performance indices.展开更多
The germination experiment was started on March 3,2004,and seeds were collected from July to October in 2003.We analyzed the percentage of germination,days to first germination,germination period and days to 50%germin...The germination experiment was started on March 3,2004,and seeds were collected from July to October in 2003.We analyzed the percentage of germination,days to first germination,germination period and days to 50%germination.Among the 54 examined species,26 species exceeded 80%germination,11 species exceeded 60%–80%germination,8 exceeded 40%–0%,5 exceeded 20%–40%,and 4 showed less than 20%.A principalcomponent analysis revealed that the species were distributed along two statistically independent axes,the first primarily represented the germination rate and the second represented the time of germination process.Based on scores of germination characteristics,cluster analysis of the 54 gramineous species could be divided into 4 distinct groups:rapid,slow,intermediate germinating(germination percentage>50%),and low germinating(germination percentage<50%).The meaning of different groups to the vegetation regeneration was discussed.展开更多
Medium-and long-chain triacylglycerols(MLCT)rich in arachidonic acid(ARA)at sn-2 position were synthesized by a two-step enzymatic method.Firstly,sn-2 monoacylglycerols(MAG)were synthesized at a temperature of 25℃ by...Medium-and long-chain triacylglycerols(MLCT)rich in arachidonic acid(ARA)at sn-2 position were synthesized by a two-step enzymatic method.Firstly,sn-2 monoacylglycerols(MAG)were synthesized at a temperature of 25℃ by enzymatic alcoholysis.The MAG with 69.42%ARA at sn-2 position were obtained by solvent extraction and low temperature solvent crystallization.Secondly,the MLCT rich in ARA at sn-2 position and capric acid(CA)at sn-1,3 positions were produced by enzymatic esterification.Under the optimal conditions(MAG:CA=1:3(mol/mol),0.05 MPa vacuum,8% Lipozyme RM IM,5 h,25℃),the content of triacylglycerol was up to 93.60%.The triacylglycerol in the form of C10:0-C20:4-C10:0(including isomers)was about 40.43%.The ARA contents in the total and sn-2 fatty acid composition of the final product were 32.35%and 51.12%,respectively.MLCT rich in ARA at sn-2 position were successfully produced and the product has the potential application for functional food and infant formula.展开更多
The cereals and their products,which have been easily infected by fungi and contaminated with mycotoxins,are serious threat to both human and animals alike.And yet,detection of these unknown fungal infection and mycot...The cereals and their products,which have been easily infected by fungi and contaminated with mycotoxins,are serious threat to both human and animals alike.And yet,detection of these unknown fungal infection and mycotoxins contaminates remains a great challenge.In this work,a holistic approach based on multiple characteristic structure fragments scans and high-resolution mass spectrometry(HRMS)was proposed for discovering unknown structural analogues of mycotoxins.The structural similarity of the same class of compounds provides a direction for the discovery and identification of unknown structural analogues of mycotoxins.The following steps were carried out:the fragmentation pathways of four types of mycotoxins were elucidated through comprehensive fragment analysis.By the combination of fragmentation pathways,the multiple characteristic structure fragments were screened out,with the common fragments were obtained by Veen diagram.Finally multiple characteristic structure fragments scans were carried out to find the unknown structural analogues of mycotoxins.The approach,first proposed by us,was proved to be effective in discovering and identifying 5 structural analogues of mycotoxins in real samples.It was proved to be a simple,fast and accurate method for early detection of fungal infection and mycotoxin contaminants,even for trace amounts of chemicals in complex matrix,and is of great significance to prevent hazardous substances infection from the food supply chains worldwide.展开更多
基金financially supported by the National Natural Science Foundation of China (51778289)the Transportation Science and Technology Project of Jiangsu Province (2014Y01)the Science and Technology Plan Project of Jiangsu Province (BY2016005-12)
文摘Thermo-elastic analysis of simply-supported orthotropic laminated beams subjected to high temperature and mechanical load is presented on the basis of the exact two-dimensional thermoelasticity theory.The beam is composed of several orthotropic layers,each with temperaturedependent material properties.The governing equation for each layer is analytically solved using the state space method.The displacement and stress solutions of the beam are obtained using the transfer-matrix method.A numerical example is included to study the effects of temperature on the mechanical responses of a sandwich beam.The results reveal two main effects of temperature:(i)inducing deformations and stresses by itself;(ii)affecting the deformations and stresses induced by the mechanical load.
基金This work was financially supported by the National Key Research and Development Program of China(2017YFC1601600)the Foundation of Chinese Academy of Inspection and Quarantine(2022JK02).
文摘Due to the lack of effective assessment method,overheated milk commodities are often marketed as pasteurized milk on the market,which was sold in high price by fraud.Thus,this article aims to establish an approach based on metabolomics to monitor thermal processing temperature of bovine milk.Metabolomics data of bovine milk samples heated at temperatures ranging from 60℃to 150℃were achieved by ultra-performance liquid chromatography-high-resolution mass spectrometry(UPLC-HRMS)platform,followed by multivariate data analysis.A regular variation pattern of chemical composition as temperature rises was pictured,furthermore.N^(∈)carboxymethyl lysine(CML),N^(∈)-carboxyethyl lysine(CEL),pentosidine.pvrraline and lysinoalanine(LAL)were identified as 5 of the most contributed compounds to discriminate pasteurized and ultra-high-temperature(UHT)milk.By the comprehensive study on their content changes,we concluded that the optimal temperature range was 90-100℃for the generation of CML and CEL in this experiment,moreover.110~120℃for LAL.S0~100℃for pentosidine and 130-140℃for pvrraline.Finally,a predicted rule to discriminate pasteurized and UHT milk was preliminarily established based on the ratios of CML/CEL.CEL/pentosidine and CML/pentosidine.which could be applied in food labelling authentication of commercial bovine milk after further validation.
基金the National Natural Science Foundation of China under Grant No.11201408.
文摘We propose a fluid model driven by the queue length process of a working vacation queue with PH service distribution, which can be applied to the Ad Hoc network with every data group. We obtain the stationary distribution of the queue length in driving process based on a quasi-birth-and-death process. Then, we analyze the fluid model, and derive the differential equations satisfied by the stationary joint distribution of the fluid queue based on the balance equation. Moreover, we obtain some performance indices, such as, the average throughput, server utilization and the mean buffer content. These indices are relevant to pack transmission in the network, and they can be obtained by using the Laplace Transform (LT) and the Laplace-Stieltjes Transform (LST). Finally, some numerical examples have been discussed with respect to the effect of several parameters on the system performance indices.
基金supported by the Chinese Key Project for Nature Science (No.90202009).
文摘The germination experiment was started on March 3,2004,and seeds were collected from July to October in 2003.We analyzed the percentage of germination,days to first germination,germination period and days to 50%germination.Among the 54 examined species,26 species exceeded 80%germination,11 species exceeded 60%–80%germination,8 exceeded 40%–0%,5 exceeded 20%–40%,and 4 showed less than 20%.A principalcomponent analysis revealed that the species were distributed along two statistically independent axes,the first primarily represented the germination rate and the second represented the time of germination process.Based on scores of germination characteristics,cluster analysis of the 54 gramineous species could be divided into 4 distinct groups:rapid,slow,intermediate germinating(germination percentage>50%),and low germinating(germination percentage<50%).The meaning of different groups to the vegetation regeneration was discussed.
基金supported by the National Natural Science Foundation of China(31601433)Jiangsu Province Natural Science Foundation(BK20140149).
文摘Medium-and long-chain triacylglycerols(MLCT)rich in arachidonic acid(ARA)at sn-2 position were synthesized by a two-step enzymatic method.Firstly,sn-2 monoacylglycerols(MAG)were synthesized at a temperature of 25℃ by enzymatic alcoholysis.The MAG with 69.42%ARA at sn-2 position were obtained by solvent extraction and low temperature solvent crystallization.Secondly,the MLCT rich in ARA at sn-2 position and capric acid(CA)at sn-1,3 positions were produced by enzymatic esterification.Under the optimal conditions(MAG:CA=1:3(mol/mol),0.05 MPa vacuum,8% Lipozyme RM IM,5 h,25℃),the content of triacylglycerol was up to 93.60%.The triacylglycerol in the form of C10:0-C20:4-C10:0(including isomers)was about 40.43%.The ARA contents in the total and sn-2 fatty acid composition of the final product were 32.35%and 51.12%,respectively.MLCT rich in ARA at sn-2 position were successfully produced and the product has the potential application for functional food and infant formula.
基金This work was financially supported by National Key Research and Development Program of China(2018YFC1602702)National“Ten thousand Plan”Scientific and Technological Innovation Leading Talent Project(Feng ZHANG).
文摘The cereals and their products,which have been easily infected by fungi and contaminated with mycotoxins,are serious threat to both human and animals alike.And yet,detection of these unknown fungal infection and mycotoxins contaminates remains a great challenge.In this work,a holistic approach based on multiple characteristic structure fragments scans and high-resolution mass spectrometry(HRMS)was proposed for discovering unknown structural analogues of mycotoxins.The structural similarity of the same class of compounds provides a direction for the discovery and identification of unknown structural analogues of mycotoxins.The following steps were carried out:the fragmentation pathways of four types of mycotoxins were elucidated through comprehensive fragment analysis.By the combination of fragmentation pathways,the multiple characteristic structure fragments were screened out,with the common fragments were obtained by Veen diagram.Finally multiple characteristic structure fragments scans were carried out to find the unknown structural analogues of mycotoxins.The approach,first proposed by us,was proved to be effective in discovering and identifying 5 structural analogues of mycotoxins in real samples.It was proved to be a simple,fast and accurate method for early detection of fungal infection and mycotoxin contaminants,even for trace amounts of chemicals in complex matrix,and is of great significance to prevent hazardous substances infection from the food supply chains worldwide.
