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Novel zeolitic Brønsted acid sites have been synthesized via grafting of extra-framework silica in H-MFI next to conventional Brønsted acid sites. The proximity of both functional groups leads to hydrogen bonding and strengthens the interaction with pyridine and amines via van der Waals force with their alkyl chains. This new site increases the reaction rate of protolytic cracking of n-pentane via a mechanism different from extra lattice alumina by stabilizing the transition state enthalpically. Durch chemische Verankerung von Si(OH)x Gruppen an Sauerstoffe des Zeolithgerüsts wurden neue zeolithische Brønsted-saure Zentren in H-MFI-Zeolithen synthetisiert. Die Nähe der Si(OH)x Gruppen zu Brønsted sauren Zentren führt zur Ausbildung von Wasserstoffbrücken. Dies resultierte starken Wechselwirkungen mit Pyridin und Aminen. Dies führte zu einer höheren Reaktionsgeschwindigkeit des protolytischen Spaltens von n-Pentan. Die neuen Zentren zeigten eine deutlich niedrigere Aktivierungsenergie für die Reaktion.

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. Graphical abstract.

A rapid and effective pre-treatment method based on immune-magnetic separation (IMS) with enrichment culture was developed to rapidly detect trace levels of Salmonella. Immune-magnetic beads were prepared and their capture efficiency exceeded 90% with less than 106 CFU/mL of Salmonella. IMS was performed on 25-mL samples without pre-enrichment; instead, the trapped target pathogens were cultured in buffered peptone water for a short time. This pre-treatment was significantly shorter and simpler: the 5 h processing time included IMS for 1 h and enrichment for 4 h. Enzyme-linked immunosorbent assay, loop-mediated isothermal amplification test, and fluorescence quantitative real-time PCR in combination with the pre-treatment method allowed detection of 10−1 CFU/mL of Salmonella (12.3 CFU in 25 mL of milk) in approximately 6.5–8 h. The pre-treatment method developed in this study was effective and can be applied to rapid screening of trace pathogens in liquid food samples.

As1 an important part of international grain trade, the trade volume of soybeans has continued to grow year by year, and its related research has received increasing attention from many scholars. This paper studies the global soybean trade data from 2000 to 2014, and built an international soybean trade network based on complex networks with the countries as the nodes and the inter-state trade relationships as the network links. Topological characteristics and their evolution, such as the average path length of the international soybean trade network, network clustering, network structure entropy, network reciprocity, etc. are mainly studied in this paper. The results show that in the international soybean trade, the trade relationship between countries is getting closer and closer. The heterogeneity of the network is not strong since some countries play important roles in the international soybean trade market while some countries have less participation. The international soybean trade network is a reciprocal network with the reciprocity between countries gradually increasing. This work explored the evolution of international soybean trade and provided a valuable reference for China to better participate in the international soybean trade market. At the same time, based on JAVA technology, the international soybean trade visualization tool and online service system have been developed as a practical feasibility solution for such applications.

This article analyzed the importance of information monitoring and quick response on agricultural focuses and significant events, proposed the workflow and technical framework for information monitoring and quick response based on modern information technologies, and explained key technologies during implementation and the functional structure for prototype system of the technical support platform.

This paper gives brief introduction about the big data, linked data and knowledge organization systems (KOS) and their relationships. As the authors mainly focus on the variety and value characteristics of big data, the linked data and KOS technologies are used to link and consume the large amounts of literature and scientific data in agricultural research community. The results show that it is a good way to describe, connect, organize, represent, visualize and access to big data effectively and semantically based on the linked data and KOS technologies.

International audience; Scientific researchers’ increasing demand for knowledge service under the new situation, makes it urgent to embed information service into user research process, ad build an incorporate knowledge platform that integrates knowledge, skills, tools, and services of certain professional field. This paper put forward the technical solution of agricultural domain knowledge service platform based on ontology, including resource organization based on ontology, platform design and development. The construction progress of ontology base and service functions based on ontology are shown by application practice in rice domain.