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High-efficiency Planting Techniques of Five Crops a Year for Fresh Edible "Faba Bean/Spring Mazie+Soybean-Autumn Maize/Autumn Soybean"
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作者 葛红 汪凯华 +4 位作者 王学军 陈满峰 缪亚梅 顾春燕 单志良 《Agricultural Science & Technology》 CAS 2016年第4期833-837,共5页
The high-efficiency planting mode for five crops a year of fresh edible "faba bean/spring maize+soybean-autumn maize/autumn soybean" was introduced, and its yield and economic benefits were compared with the planti... The high-efficiency planting mode for five crops a year of fresh edible "faba bean/spring maize+soybean-autumn maize/autumn soybean" was introduced, and its yield and economic benefits were compared with the planting mode of three crops a year of "faba bean-spring maize/red bean". The results showed that the planting method for fresh edible "faba bean/spring maize+soybean-autumn maize/autumn soybean" was much easier to operate with the input-output ratio of about185.6%, and its yield and economic benefits were 2.09 and 1.83 times of that of the planting mode for three crops a year, significantly improving the agricultural yield and income of farmers. In addition, the cropping index of the planting mode for fresh edible fresh edible "faba bean/spring maize +soybean-autumn maize/autumn soybean" reached up to 350%, and planting faba bean once a year and soybean twice a year could make the biological fixation amount of nitrogen increase 350-450kg/m^2, which equaled to up to 700 kg/m^2 of urea, showing significant ecological and social benefits. Based on the comparison results, the high-yield culture techniques of the planting mode of fresh edible "faba bean/spring maize+soybean-autumn maize/autumn soybean" were summarized. 展开更多
关键词 fresh edible faba bean fresh edible maize fresh edible soybean Five crops a year High-efficiency planting mode
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Abomasal infusion of branched-chain amino acids or branched-chain keto-acids alter lactation performance and liver triglycerides in fresh cows
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作者 Kristen Gallagher Isabelle Bernstein +7 位作者 Cynthia Collings David Main Ghayyoor Ahmad Sarah Naughton Jayasimha Daddam Vengai Mavangira Mike Vandehaar Zheng Zhou 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1145-1157,共13页
Background Dairy cows are at high risk of fatty liver disease in early lactation,but current preventative measures are not always effective.Cows with fatty liver have lower circulating branched-chain amino acid(BCAA)c... Background Dairy cows are at high risk of fatty liver disease in early lactation,but current preventative measures are not always effective.Cows with fatty liver have lower circulating branched-chain amino acid(BCAA)concentra-tions whereas cows with high circulating BCAA levels have low liver triglyceride(TG).Our objective was to determine the impact of BCAA and their corresponding ketoacids(branched-chain ketoacids,BCKA)on production performance and liver TG accumulation in Holstein cows in the first 3 weeks postpartum.Methods Thirty-six multiparous Holstein cows were used in a randomized block design experiment.Cows were abomasally infused for the first 21 d postpartum with solutions of 1)saline(CON,n=12);2)BCA(67 g valine,50 g leu-cine,and 34 g isoleucine,n=12);and 3)BCK(77 g 2-ketovaline calcium salt,57 g 2-ketoleucine calcium salt,and 39 g 2-ketoisoleucine calcium salt,n=12).All cows received the same diet.Treatment effects were determined using PROC GLIMMIX in SAS.Results No differences were detected for body weight,body condition score,or dry matter intake averaged over the first 21 d postpartum.Cows receiving BCK had significantly lower liver TG concentrations compared to CON(6.60%vs.4.77%,standard error of the mean(SEM)0.49)during the first 3 weeks of lactation.Infusion of BCA increased milk yield(39.5 vs.35.3 kg/d,SEM 1.8),milk fat yield(2.10 vs.1.69 kg/d,SEM 0.08),and lactose yield(2.11 vs.1.67 kg/d,SEM 0.07)compared with CON.Compared to CON,cows receiving BCA had lower plasma glucose(55.0 vs.59.2 mg/dL,SEM 0.86)but higherβ-hydroxybutyrate(9.17 vs.6.00 mg/dL,SEM 0.80).Conclusions Overall,BCAA supplementation in this study improved milk production,whereas BCKA supplementa-tion reduced TG accumulation in the liver of fresh cows. 展开更多
关键词 Branched-chain amino acids Branched-chain ketoacids Fatty liver fresh cow
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Mixed Integer Robust Programming Model for Multimodal Fresh Agricultural Products Terminal Distribution Network Design
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作者 Feng Yang Zhong Wu Xiaoyan Teng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期719-738,共20页
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
关键词 fresh agricultural product terminal distribution network rider delivery robot delivery UNCERTAINTY
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Effects of Functional Organic Materials on Fresh Weight,Quality,Single-melon Weight and SPAD Value of Watermelon
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作者 Kun CHEN Yuefeng ZHAO +5 位作者 Xiaoxue REN Mingda YANG Mingjun ZHAO Yumei WANG Xinhua HUANG Hao LIU 《Agricultural Biotechnology》 2024年第4期54-56,共3页
[Objectives]This study was conducted to explore a functional organic material formula suitable for watermelon cultivation with high quality,high yield and high efficiency.[Methods]Four treatments were set in the exper... [Objectives]This study was conducted to explore a functional organic material formula suitable for watermelon cultivation with high quality,high yield and high efficiency.[Methods]Four treatments were set in the experiment,namely four functional organic materials,garlic straw treatment(T_(1)),onion straw treatment(T_(2)),garlic straw+sheep manure treatment(T_(3))and onion straw+chicken manure treatment(T_(4)),to investigate the effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon.[Results]The effects of different functional organic materials on fresh weight,quality,single-melon weight and SPAD value of watermelon were quite different.The fresh weight,quality,single-melon weight and SPAD value of watermelon were higher in treatment T_(3)applying garlic straw and sheep manure and treatment T_(4)applying onion straw and chicken manure than in treatment T_(1)applying garlic straw and treatment T_(2)applying onion straw.Specifically,the fresh weight of whole plant was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 12.83%and 5.94%respectively compared with treatment T_(1);the weight of single melon was the highest in treatment T_(3),followed by treatment T_(4),and the values of the two treatments increased by 42.45%and 31.77%respectively compared with treatment T_(2);and the SPAD values of treatments T_(3)and T_(4)were significantly higher than those of treatments T_(1)and T_(2),and the value of treatment T_(3)was the largest.[Conclusions]This study provides theoretical support for the popularization and application of fertilization techniques combining organic fertilizers and reduced chemical fertilizers for watermelon. 展开更多
关键词 WATERMELON Organic materials fresh weight QUALITY Single-melon weight SPAD value
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Fresh Processing Technology in Polygonatum odoratum Production Area and Its Comparison with Traditional Processing
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作者 Miao YANG Chufan PENG +4 位作者 Haixia LU Rufeng LIANG Hui TANG Zhongmei QIN Shengjiu GU 《Medicinal Plant》 2024年第1期38-40,44,共4页
[Objectives]To compare the effects of traditional processing and fresh processing on the quality of Polygonatum odoratum decoction piece.[Methods]The effects of fresh processing and traditional processing on the quali... [Objectives]To compare the effects of traditional processing and fresh processing on the quality of Polygonatum odoratum decoction piece.[Methods]The effects of fresh processing and traditional processing on the quality of P.odoratum decoction piece were compared and analyzed with appearance characteristics,total ash content,extract content,total polysaccharides content,and total flavonoids content as the evaluation indexes.[Results]Fresh processing method in different production areas has different effects on P.odoratum decoction piece.P.odoratum was dried in oven of 50℃.When moisture content was 41.44%-59.67%,it was cut.After complete drying at 50℃,the moisture content of dried P.odoratum was 8.94%-9.60%,and ethanol-soluble extract content was 77.29%-78.20%,and water-soluble extract was 77.7%-78.14%.At this time,the appearance characteristics of section of P.odoratum decoction piece were better than that of traditional processing,which was yellowish white.The total polysaccharide content was higher than that of traditional processing,and the content of total flavonoids was statistically significant different from that of traditional processing.[Conclusions]The quality of P.odoratum decoction piece by fresh processing is better than that of the traditional processing,and it is feasible to use fresh processing. 展开更多
关键词 Processing technique Plygonatum odoratum fresh processing Total polysaccharide Total flavonoids
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Physico-Chemical and Microbiological Study of Fresh Pineapple(Baronne de Guinée)Grown in the Sub-prefectures of:Maferinyah and Friguiagbé(Forécariah and Kindia Prefectures),Republic of Guinea
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作者 Sâa Gérard Tolno Haicha Cissé +3 位作者 Amadou Sylla Mamadou Madaniou Sow Adama Moussa Sakho Lounceny Traore 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第6期211-217,共7页
Pineapple fruit in the Republic of Guinea is currently less competitive in the West African sub-region due to the nutritional quality of the product.Thus,it is normal to review certain parameters such as:sensory,physi... Pineapple fruit in the Republic of Guinea is currently less competitive in the West African sub-region due to the nutritional quality of the product.Thus,it is normal to review certain parameters such as:sensory,physico-chemical in order to improve this classification.To do this,instead of buying samples on the market,the aim is to analyze fresh samples harvested in the production fields and send them to the laboratory for analysis of certain physico-chemical and microbiological parameters.Analytical results showed that the Brix content in fields I and II at Maferinyah(Forécariah)was higher(14.35 and 16.5)than that found in fields I and II at Friguiagbé(Kindia)(14.2 and 12.4),The pH of fruit from both localities varies between 3.48 and 3.56,with the highest acidity value found in Field I at Friguiagbé(Kindia)2.16 and the lowest value in Field II at Maferinyah(Forécariah)0.46.Moisture contents for both localities ranged from 82.56 to 89.5,with the highest value found at Field I in Maferinyah(Forécariah)89.5.Dry extract and ash in both localities would be in the range 10.54 to 17.45;0.33 to 1.43 respectively.The highest values for dry extract and ash were found in Fields I and II Friguiagbé(Kindia)17.45 and 1.43.The samples analyzed contained certain trace elements such as magnesium,sodium,iron and phosphorus.Microbiological analyses showed the presence of Escherichia coli(E.coli),yeast-molds,Staphylococcus aureus and the absence of salmonella. 展开更多
关键词 fresh pineapple cultivated physicochemical study microbiology
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Multivariate Regression Analysis on Correlated Characters about Fresh Pod Yield of Fresh Edible Soybean
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作者 葛长军 闫良 +1 位作者 徐丽荣 罗九玲 《Agricultural Science & Technology》 CAS 2015年第4期687-690,共4页
Objective] The alm was to survey 10 characters of 8 fresh edibIe soy-bean varieties, analyze maln Ioading factors using principal component analysis, and estabIish muItipIe regression equation on fresh pod yield. [Met... Objective] The alm was to survey 10 characters of 8 fresh edibIe soy-bean varieties, analyze maln Ioading factors using principal component analysis, and estabIish muItipIe regression equation on fresh pod yield. [Methods] Through princi-pal component analysis on 10 characters of 8 fresh edibIe soybean varieties, char-acters reIated to fresh pod yield of fresh edibIe soybean were cIarified. [Results] Af-ter the principal components analysis, pod weight per pIant, 100-seed weight and pod number per pIant of fresh edibIe soybean were chosen to study their reIation with the yield of fresh edibIe soybean, moreover, it was demonstrated that the reIa-tion was Iinear reIation, thus it was suitabIe for muItivariate regression analysis. Fi-nal y, the mathematical expression formuIa about fresh pod yield was estabIished. [Conclusions] There were three characters affecting fresh pod yield, nameIy, pod weight per pIant, 100-seed weight and pod number per pIant, the mathematical equation was y=816.732+4.145X6-0.718X8-0.985X9 (X6: pod weight per pIant; X8: 100-seed weight; X9: pod number per pIant). 展开更多
关键词 fresh edible soybean fresh pod yleId Principal component analysis MuItiple regresslon equatlon
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Effect of Different Nitrogen Application Amount on the Net Increment of Fresh Dry Weight in Hybrid Rape 被引量:19
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作者 任廷波 赵继献 《Agricultural Science & Technology》 CAS 2008年第2期147-151,共5页
[ Objective] The aim of the research was to provide reference for reasonable application of nitrogen fertilizer for high yield.cultivation of hybrid rape cuhivar Youyan 9 and Youyan 10. [ Method] The net increment cha... [ Objective] The aim of the research was to provide reference for reasonable application of nitrogen fertilizer for high yield.cultivation of hybrid rape cuhivar Youyan 9 and Youyan 10. [ Method] The net increment changes of individual plant fresh weight and dry matter weight of Youyan 9 and Youyan 10 with different nitrogen application treatments were studied. [ Result] The differences among average fresh weight increments of individual plant and average dry matter weight increment of individual plant with different treatments reached 0. 01 extremely significant level. Fresh weight increment and dry matter weight net increment of individual plant declined gradually with the increase of nitrogen application. In growtheourse ,fresh weight net increment of individual plant increased firstly then decreased and the maximum was in beginning flowering stage, besides that dry matter net increment increased gradually and the maximum was in mature period. The correlations among fresh net increment, dry matter weight net increment and yield net increment were positive or extremely positive. [ Conclusion] Under experimental condition, when nitrogen application was 225 kg/hm^2, hybrid rape Yanyou 9 and Yanyou 10 with low erucic,low glucosinolate could obtain high yield. 展开更多
关键词 Hybrid rape Net increment fresh dry weight Amount of nitrogen application
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Effects of Facilities Condition on Occurrence of Freeze Injury and Fresh Pod Yield of Broad Bean 被引量:2
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作者 吴春芳 卞晓春 +1 位作者 曹云英 夏礼如 《Agricultural Science & Technology》 CAS 2015年第5期890-897,共8页
Using Tongxian No.2 as material, the effects of different film-covering time, different sowing time and different planting density on the occurrence of freeze injury and yield of fresh broad beans were investigated. T... Using Tongxian No.2 as material, the effects of different film-covering time, different sowing time and different planting density on the occurrence of freeze injury and yield of fresh broad beans were investigated. The randomized block design was adopted. The results showed that with the delayed film covering, the incidence of mild freeze injury and number of headless seedlings were increased correspondingly, but the yield was increased; with the delayed sowing, the branch number per plant, effective branch number per plant, incidence of mild freeze injury and number of headless seedlings were all reduced, and the broad beans, sowed on September 30 th, obtained the highest yield; planting density showed on effect on the occurrence of freeze injury, and the yield was increased with the increase of planting density. Under the same film-covering time, the incidence of freeze injury was reduced with the delayed sowing time and it showed no changes when planting density was changed, but the yield was increased with the increase of planting density and it was highest when broad bean seeds were sowed on September 30th;under the same sowing time, the incidence of freeze injury was increased with the delayed film-covering time and it showed no changes when planting density was changed, and the yield was increased with the delayed film-covering time and increased planting density; under the same planting density, the incidence of freeze injury was increased with the delayed film-covering time but was reduced with the delayed sowing time, and the yield was increased with the delayed film-covering time and it was highest when the broad bean seeds were sowed on September30 th. Under same film-covering time and sowing time, the total branch number per plant and effective branch number per plant were reduced, but the yield was increased with the increase of planting density; under same film-covering time and planting density, the incidence of freeze injury was reduced with the delayed sowing time, and the yield was highest when broad bean seeds were sowed on September30th; under same sowing time and planting density, the incidence of freeze injury and the yield were all increased with the delayed film-covering time. 展开更多
关键词 Facility broad bean Film-covering time Sowing time Planting density Freeze injury fresh pod yield
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Research on Protected Cultivation of Fresh Faba Bean Tong Can Xian 7 被引量:1
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作者 陈满峰 赵娜 +2 位作者 汪凯华 缪亚梅 王学军 《Agricultural Science & Technology》 CAS 2015年第7期1418-1420,共3页
[Objective] The aim was to provide scientific basis for protected cultivation of faba bean. [Method] Comparative analysis of the plant height, the first pod height, the branch number per plant, the node position of fi... [Objective] The aim was to provide scientific basis for protected cultivation of faba bean. [Method] Comparative analysis of the plant height, the first pod height, the branch number per plant, the node position of first pod, the node num- ber, yield per plant, plot yield of fresh pod were studied by using Tongcanxian 7 which were planted at different seeding time and different density. [Result] The re- sults show that Tongcanxian 7 had maximum yield with 37 500 plant/hm2 when sowed on November 2. [Conclusion] Plastic greenhouse cultivation is appropriate for fresh eating faba bean, the sowing-time is the beginning of November and the best density is 7 500 plant/hm2. 展开更多
关键词 fresh faba bean Seeding time DENSITY
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Effect of Freshness Protection Package on Storage and Preservation of Chinese Cabbage 被引量:1
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作者 王希卓 孙洁 +2 位作者 张凯 杨琴 孙海亭 《Agricultural Science & Technology》 CAS 2016年第12期2742-2745,2808,共5页
The effect of freshness protection package on Chinese cabbage placed in the self-made shelf in ventilated storage was investigated, and the physiological-qual-ity indexes change were determined during the storage peri... The effect of freshness protection package on Chinese cabbage placed in the self-made shelf in ventilated storage was investigated, and the physiological-qual-ity indexes change were determined during the storage period. The results showed that the losses of weight and vitamin C were significantly reduced. The accumula-tion of crude fiber was effectively inhibited. But protein content was maintained at a low level and the rotting more serious of Chinese cabbage at the end of the stor-age packaged with the fresh keeping bags. 展开更多
关键词 freshness protection package Chinese cabbage PRESERVATION Ventilat-ed storage
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新零售背景下生鲜电商线上线下整合模式研究——以京东7fresh为例 被引量:7
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作者 万丽丽 《内蒙古财经大学学报》 2019年第3期20-24,共5页
随着我国电子商务市场的繁荣、O2O模式的发展和二维码扫码技术的成熟,生鲜电商利用线上线下深度融合经营优势,推动了新零售背景下传统生鲜行业的转型升级。本文以生鲜电商线上线下整合模式典型代表京东7fresh为例,从消费者行为理论出发... 随着我国电子商务市场的繁荣、O2O模式的发展和二维码扫码技术的成熟,生鲜电商利用线上线下深度融合经营优势,推动了新零售背景下传统生鲜行业的转型升级。本文以生鲜电商线上线下整合模式典型代表京东7fresh为例,从消费者行为理论出发,基于SICAS理论和问卷调查的结果,分析京东7fresh在网络营销中存在的问题,并提出相应的优化策略。 展开更多
关键词 新零售 生鲜电商 SICAS理论 京东7fresh
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14.6 tex Modal Fresh/棉混纺纱的生产实践 被引量:1
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作者 王俊英 《上海纺织科技》 北大核心 2008年第2期18-19,42,共3页
介绍了Modal Fresh纤维的特性,阐述了Modal Fresh纤维与棉混纺生产中应注意的几个问题,并按开清棉、梳棉、并粗、细纱和络筒工序进行了叙述。
关键词 混纺 纺纱 工艺流程 MODAL fresh纤维
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Effects of Salinity and Freezing on Freshness of Crucian
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作者 高桂生 史秋梅 +5 位作者 葛慕湘 陈娟 苏咏梅 董玉玲 韩红升 宋青春 《Agricultural Science & Technology》 CAS 2015年第12期2791-2794,2800,共5页
Salt tolerance and freeze preservation of crucian are always important concerns of people. There are rare reports on effect of different salinity on fresh- ness and quality. However, water salinity will directly affec... Salt tolerance and freeze preservation of crucian are always important concerns of people. There are rare reports on effect of different salinity on fresh- ness and quality. However, water salinity will directly affect osmotic pressure in fish, thereby affecting meat quality. In this study, the tolerance of crucian to different salinities (1‰, 2‰, 5‰, 8‰, 10‰ and 15‰) was investigated. In addition, the ef- fect of different salinity on freezing freshness and quality of crucian was studied. The results showed that the tolerance threshold of crucian to salinity was about 8‰, and the freezing quality of crucian in water with salinity of ‰ was significantly better than that in fresh water. 展开更多
关键词 Crucian SALINITY Salt tolerance freshNESS
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Effect of Disinfection Time on Microbial Content and Quality of Cold Fresh Chicken
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作者 王合叶 赵永富 冯敏 《Agricultural Science & Technology》 CAS 2017年第3期476-477,489,共3页
[Objective] The aim was to provide reference for the production technolo- gy of cold fresh chicken. [Method] Lactic acid was used as the disinfectant in cooling water, so as to study the effect of disinfection time on... [Objective] The aim was to provide reference for the production technolo- gy of cold fresh chicken. [Method] Lactic acid was used as the disinfectant in cooling water, so as to study the effect of disinfection time on the microbial content and quality of cold fresh chicken. [Result] With disinfection of 20 min, the removal rates of the total colonies, coliforms and moulds reached over 95%. As the disinfec- tion time was further extended, it had no significant effect on the removal effects of the microbial content and could affect the tenderness and color of cold fresh chick- en. [Cendusion] The study provides references for the design and optimization of the production process of cold fresh chicken. 展开更多
关键词 Cold fresh chicken Disinfection time Total Colonies COLIFORMS MOULDS Meat Tenderness
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Fresh的非常知识
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作者 杨红 《科教探索》 2008年第10期172-172,共1页
英文到底有多难学?几乎每一个英语学习者都有一堆困惑等待解答,即使是语言学界的前辈们也是孜孜以求,不敢轻言“精通”二字,实在是因为他们多年耕耘,深知知识海洋的浩瀚,正应了那句老话——“学后知不足”。虽然英语不同于法语中... 英文到底有多难学?几乎每一个英语学习者都有一堆困惑等待解答,即使是语言学界的前辈们也是孜孜以求,不敢轻言“精通”二字,实在是因为他们多年耕耘,深知知识海洋的浩瀚,正应了那句老话——“学后知不足”。虽然英语不同于法语中几乎所有的事物都有阴性、阳性之分,但是几乎每一个词都有几个不同的词义和词性用法,其中细微精妙的语意差别,用得不妥当便会造成尴尬。事实上,在阅读中。我们通常会对一些自己认识的简单词理解困难,学习不得要领。 展开更多
关键词 fresh 非常知识 英语教学 语言学
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基于fresh-slice的全相干X射线自由电子激光飞秒脉冲产生原理 被引量:1
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作者 高张峰 颜佳伟 +2 位作者 邓海啸 刘波 王东 《核技术》 CAS CSCD 北大核心 2021年第7期1-8,共8页
X射线自由电子激光(Free-Electron Laser,FEL),尤其是全相干飞秒FEL脉冲,在众多领域都有应用。依托上海软X射线自由电子激光用户装置(Shanghai Soft X-ray Free-Electron Laser User Facility,SXFEL-UF),提出了一种基于fresh-slice技术... X射线自由电子激光(Free-Electron Laser,FEL),尤其是全相干飞秒FEL脉冲,在众多领域都有应用。依托上海软X射线自由电子激光用户装置(Shanghai Soft X-ray Free-Electron Laser User Facility,SXFEL-UF),提出了一种基于fresh-slice技术产生全相干飞秒X射线脉冲的原理。通过对电子束施加横向踢力使其产生时间关联的横向倾斜,再利用种子激光调制的时空同步获得亚十飞秒尺度的群聚。对于SXFEL-UF的级联高增益谐波产生(High-Gain Harmonic Generation,HGHG)模式,三维模拟结果表明得到种子激光45次谐波的峰值功率为3 GW,脉冲长度为3.3 fs,X射线脉冲长度随束团横向倾斜程度的变化关系与理论预期吻合;单级回声型谐波产生(Echo-Enabled Harmonic Generation,EEHG)模式的三维模拟结果与之接近。通过进一步分析电子束团的横向发射度、能量啁啾、横向位置抖动和中心能量抖动对该方案结果的影响,探索了利用椭圆极化波荡器Afterburner同时获得6 nm的飞秒线偏光和3 nm的飞秒圆偏光的方案。 展开更多
关键词 X射线 飞秒脉冲 能量啁啾 fresh-Slice 圆偏振
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Changes of moisture distribution and migration in fresh ear corn during storage 被引量:15
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作者 WANG Hao LIU Jing-sheng +2 位作者 MIN Wei-hong ZHENG Ming-zhu LI Hao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第11期2644-2651,共8页
Understanding of moisture changes in fresh ear corn(Zea mays L.)during storage is imperative for maintaining fresh corn quality.The changes of moisture distribution and migration in fresh ear corn during storage were ... Understanding of moisture changes in fresh ear corn(Zea mays L.)during storage is imperative for maintaining fresh corn quality.The changes of moisture distribution and migration in fresh ear corn during storage were investigated using low-field nuclear magnetic resonance(NMR)and magnetic resonance imaging(MRI).Water loss was greater than water migration in fresh ear corn within the first hour of storage;thereafter,water loss was weaker than water migration.With the extension of storage time,the signal intensity of MRI in different parts of sliced fresh corn with cob showed a downward trend,and the rate of signal intensity reduction was higher in the peripheral area than at the central part of sliced fresh corn with cob.The relative proportion of bound water increased with a concomitant drop in that of free water,when the total water content reduced in fresh ear corn under storage.In conclusion,NMR and MRI are useful and non-destructive tools for real-time monitoring of moisture distribution,migration,and loss in fresh ear corn during storage to assess its quality.These results can be used for future design of the preserving and processing conditions for fresh ear corn. 展开更多
关键词 fresh EAR CORN NMR MRI MOISTURE distribution MOISTURE MIGRATION
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Electronic Nose with an Air Sensor Matrix for Detecting Beef Freshness 被引量:33
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作者 Zhe Zhang Jin Tong +1 位作者 Dong-hui Chen Yu-bin Lan 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第1期67-73,共7页
China is one of the largest meat producing countries in the wodd. With the growing concern for food safety more attention has been paid to meat quality. The application of conventional test methods for meat quality is... China is one of the largest meat producing countries in the wodd. With the growing concern for food safety more attention has been paid to meat quality. The application of conventional test methods for meat quality is limited by many factors, and subjectiveness, such as longer time to prepare samples and to test. A sensor matrix was constructed with several separate air sensors, and tests were conducted to detect the freshness of the beef. The results show that the air sensors TGS2610, TGS2600, TGS2611, TGS2620 and TGS2602 made by Tianjin Figaro Electronic Co, Ltd could be used to determine the degree of freshness but TGS2442 is not suitable. This study provides a foundation for designing and making an economical and practical detector for beef freshness. 展开更多
关键词 gas sensitive sensor matrix degree of beef freshness electronic nose
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Response of IAP/LASG GOALS Model to the Coupling of Air-Sea Fresh Water Exchange 被引量:12
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作者 周天军 张学洪 +3 位作者 俞永强 宇如聪 刘喜迎 金向泽 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第3期473-486,共14页
The process of air—sea fresh water exchange is included successfully in the Global— Ocean—Atmosphere Land—System model developed at the State Key Laboratory of Atmospheric Sciences and Geophysical Fluid Dynamics (... The process of air—sea fresh water exchange is included successfully in the Global— Ocean—Atmosphere Land—System model developed at the State Key Laboratory of Atmospheric Sciences and Geophysical Fluid Dynamics (LASG). The results of the coupled integration show that the climate drift has been controlled successfully. Analyses on the responses of ocean circulation to the changes of surface fresh water or salinity forcing show that the ocean spin-up stage under flux condition for salinity is the key to the implementation of air-sea fresh water flux coupling. This study also demonstrates that the Modified—Monthly—Flux—Anomaly coupling scheme (MMFA) brought forward by Yu and Zhang (1998) is suitable not only for daily air—sea heat flux coupling but also for daily fresh water flux coupling. Key words Fresh water flux - Air-sea coupling - Thermohaline circulation This work was co-supported by the National Key Project (Grant No.96-908-02-03), the Excellent National Key Laboratory Research Project (Grant No.49823002) and Chinese Academy of Sciences (CAS) under grant “ Bai Ren Ji Hua? for “Validation of Coupled Climate Models”. 展开更多
关键词 fresh water flux Air-sea coupling Thermohaline circulation
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