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[行业报告] European Ag Machinery Industry in Recession 进入全文

欧盟农业机械协会(CEMA)

The general business climate index of the agricultural machinery industry in Europe is further deteriorating. Meanwhile, the industry is clearly in recession. The business climate is now negative across all segments. Manufacturers of arable and livestock equipment appear to be particularly affected. On an industry average, not only current business evaluations and turnover expectations are negative. Almost half of the participants also expect further declines in incoming orders (while only nearly one in ten expects an increasing order intake). A slowdown of the downward trend is thus not in sight. On the European market side, according to the survey, the outlook for the UK is the worst and has reached a new low. France remains as the only positive exception, where a majority of survey participants still expect turnover increases. France is also the only European market where participants report that dealer stock levels with new machines are currently not above the average of the past three years. The highest above-average stocks with new machines can be seen in the UK and Germany. Dealer stock levels with used machines seem to be above average in all segments throughout Europe.

[学术文献] Label-free impedimetric biosensors for the control of food safety - a review 进入全文

INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY

The guarantee of food safety requires fast and accurate control for all contaminants, chemicals and bacteria, which are harmful to human health. Ensuring the safety and quality of food is the main interest both for the food industry and for consumers. In the food industry, the safety of a food product is evaluated through chemical and microbiological analysis: these procedures conventionally use the technique as chromatography, spectrophotometry and electrophoresis that are time-consuming, require highly trained personnel, are expensive and require steps of sample pretreatment, increasing the time of analysis. Consequently, among food and beverage industries, exists a growing demand in biosensing technologies as simple, rapid, accurate, low – cost and portable analytical devices for the monitoring and detection of chemical and microbiological contaminants (toxins, mycotoxins, pathogenic bacteria, pesticides and allergens) that endanger the food safety. Among biosensors, the label-free biosensors, characterised by direct detection of the analyte of interest, exploiting the advantages of an impedimetric transduction technique, seem to be the most promising devices for the future. In the last years, the potential use of Electrochemical Impedance Spectroscopy technique has been widely considered in the biosensor field; it is, in fact, a powerful, non-destructive and informative technique which can be used to study the electrical properties of the sensing device interface and to trace the reactions that occur on it. For these reasons, the application of impedimetric technique as a transduction technology has allowed the label-free detection and sensitive quantification of the bio interaction in different application and thus for the development of food hazards biosensors too. This review provides the current situation in the literature on label-free impedimetric biosensors in food safety.

[学术文献] Rapid detection of trace Salmonella in milk and chicken by immunomagnetic separation in combination with a chemiluminescence microparticle immunoassay 进入全文

ANALYTICAL AND BIOANALYTICAL CHEMISTRY

Rapid detection of trace Salmonella is urgently needed to ensure food safety. We present an innovative pretreatment strategy, based on a two-step enrichment culture and immunomagnetic separation, combined with a chemiluminescence microparticle immunoassay to detect at least one proliferative Salmonella cell in 25 mL (25 g) food. The capture performance of immunomagnetic beads (IMBs) of sizes for Salmonella was investigated, and the IMBs of size 2.8 μm showed a high capture efficiency of 60.7% in 25 mL milk and 74.5% in 25 mL chicken culture filtrate, which ensured the successful capture of trace Salmonella after 2.5 h in situ enrichment even from only one Salmonella cell. The separated Salmonella cells, reaching an amount of 103 colony-forming units (CFU) by a secondary enrichment for 3 h, were detected by a horseradish peroxidase chemiluminescence reaction with 4-(1-imidazolyl)phenol as an enhancer, which evidenced a linear response for Salmonella concentrations ranging from 2.3 × 102 to 7.8 × 104 CFU/mL. The entire detection process was completed within 8 h, with a very low detection limit of 1 CFU/25 mL (25 g), which was verified by colony counting, and a small degree of interference of 0.17–1.06%. Trace Salmonella from five different serovars in milk and chicken was successfully detected without false negative or false positive results. Furthermore, this study provides a basis to develop a fully automated instrument based on IMBs that includes all steps from sample preparation to chemiluminescence microparticle immunoassay for high-throughput screening of foodborne pathogens.

[学术文献] Comparative Study of Electrochemical Sensors Based on Enzyme Immobilized into Polyelectrolyte Microcapsules and into Chitosan Gel 进入全文

ANALYTICAL SCIENCES

The characteristics of an electrochemical biosensor based on a Prussian-blue screen-printed electrode containing glucose oxidase incorporated into polyelectrolyte microcapsules (PMC) are considered. PMC with the embedded enzyme were formed using sodium polystyrene sulfonate and poly(allylamine hydrochloride). The characteristics were compared with those of the enzyme immobilized in chitosan gel. We assessed the dependences of biosensor signals on the composition of the buffer solution, on the glucose concentration; the operational and long-term stabilities. The enzyme immobilized in PMC proved to be more sensitive to buffer molarity at a maximum within 35 – 40 mM. The apparent Michaelis constants were 1.5 and 4.1 mM at the immobilization in, respectively, chitosan and PMC. The developed biosensors were used to assay commercial juices. The biosensors’ data on the glucose contents were shown to have a high correlation with the standard spectrophotometric assay (0.92 – 0.95%), which implies a possible application of the fabricated biosensors in foodstuff analysis.

[相关专利] 一种温敏变色有机玻璃的制备方法 进入全文

中国知识产权局

本发明提供了一种温敏变色有机玻璃的制备方法,包括以下步骤:(1)温敏变色微胶囊的制备:准确称取结晶紫内酯、硬脂酸和十四醇,搅拌溶解,滴加吐温80的水溶液,在70℃下搅拌2h,制得A液;称取甲基丙烯酸甲酯和过氧化苯甲酰,于80℃下搅拌反应30min,制得B液,将B液滴加至A液中,在80℃下反应30~45min,过滤,水洗,烘干,制得变色微胶囊;(2)温敏变色有机玻璃的制备:称取甲基丙烯酸甲酯和过氧化苯甲酰,于85℃下搅拌反应30~60min,再加入变色微胶囊,继续搅拌5min,迅速冷却至50℃,静置1h,升温至70℃,恒温2h,再升温至100℃,恒温2~3h,制得变色有机玻璃。本发明通过将变色微胶囊与聚甲基丙烯酸甲酯原位进行本体聚合而制得温敏变色有机玻璃,产物具有变色灵敏、色泽均一的特点。

[学术文献] 论中国乡村振兴战略中的农业工程管理创新 进入全文

农业工程学报

中国农业工程为农业农村现代化筑牢基石、立梁架柱。农业工程管理创新,推动乡村产业兴旺,促进农民生活富裕,提升生态宜居水平,是实施乡村振兴战略的重要路径。但目前中国农业工程管理尚未成体系,工程管理落后于技术管理,经营主体的主体作用与积极性发挥不够等问题突出,农业工程管理方法亟待改进、管理效率亟待提高。新时代农业工程管理关键要在理念与方法上全面创新。该文基于系统论和工程管理理论,创新提出了农业工程全系统整合、全要素集成、全环节优化、全方位协同的“四全”管理方法体系,利用该方法体系分析了目标管理、过程管理、动态控制3个农业工程管理的关键环节,并提出了强化农业工程顶层设计、部门分工、立法建设、监督评价的具体建议。该方法体系可为农业工程管理提供参考。

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