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Detecting and removing pesticide and veterinary drug residues in agricultural products are important for ensuring food safety. Current methods for detecting pesticide residues are mainly relied on sophisticated instruments, which require long detection time and skilled operators, limiting their accessibility. Metal-Organic Frameworks (MOFs) are a hybrid material composed of metal ions/clusters and organic ligands. MOFs possess multiple functions such as adsorption enrichment, catalytic degradation, and fluorescent and electrochemical signal generation. Therefore, MOFs have great potential in rapidly detecting and removing pesticide and veterinary drug residues. This review introduces functionalities of MOFs: Enrichment and removal, catalytic degradation, fluorescence sensing, and electrochemical sensing, and then summarizes their applications for rapid detecting and removing pesticide and veterinary drug residues. Additionally, this article comprehensively analyzes the advantages and disadvantages about combining RGB analysis and portable monitoring devices with MOFs. Also, the challenges of applying MOFs to detecting and removing pesticide and veterinary drug residue are discussed. Overall, this paper provides a reference for developing techniques to rapidly detect and remove containments in agricultural products. [ABSTRACT FROM AUTHOR]

The failure load, failure mode, and progressive damage processes of carbon-glass hybrid composite bolted connection structures were studied by using the method of experiments and numerical simulations. Based on the ABAQUS platform, the finite element models of 36 different types of connection structures with various width to diameter ratios(W/D) and end to diameter ratios(E/ D) were established. According to the three-dimensional Hashin failure criterion and Chang-Chang failure criterion, the effects of structural dimensions E/D and W/D on the failure load and failure mode were analyzed, combined with the findings of the tensile tests. The impacts of E/D and W/D on the failure load and failure mode of the connection structures and the progressive damage processes of the connection structures under various failure modes were discussed. The results show that the failure modes of the carbon-glass hybrid composite bolted connection structures with a specific hybrid ratio include bearing failure, shear-bearing failure, and tensile failure. The structural dimensions E/D and W/D have a greater impact on the failure load and failure mode. The bearing failure mode of the connection structures is that the matrix of the laminated plates are damaged at the axis position on the extruding side of the bolt holes, and the failure extends outward in a sector shape along the axis to the structure failure. The shear-bearing failure mode is that a large number of fiber and matrix tensile damage occur from the bolt holes to the end face of the laminated plates, with the matrix bearing damage at the compression side of the bolt holes, generating a notch to the structural failure. The tensile failure mode is that the fiber and matrix tensile damage occurs at the upper and lower positions of the bolt holes of the laminates, and extends laterally to the upper and lower sides of the laminates, resulting in structural failure. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] According to the market’s demand for taste-type and fresh-eatable cabbage, more varieties of cabbage with good characters and in line with market supply and demand were selected by using its own germplasm resources. [Method] Using 13 Ougra sterile heading cabbage materials selected by the team as female parents and 10 inbred lines heading cabbage materials (GL14000-14009) as male parents, 14 heading cabbage hybrid combinations were prepared through hybridization, the experiments were compared and screened from the aspects of plant width, outer leaf number, longitudinal diameter, transverse diameter, central column length, yield and disease resistance. [Result] After comparison, GL22-02, GL22-06, GL22-11 and GL22-13 were obtained, and their agrtural traits, quality and yield were better than those of the control Tejia No. 2. All the leaf bulbs were round, and the petiole-leaf ratio was 26.9%, 20.8%, 23.1% and 16.8%. It was better than that of control variety (31.3%). Leaf bulb compactness was 0.76, 0.73, 0.59 and 0.62 g/cm3, which was more than 0.16 g/cm3 higher than that of the control variety. The central column length was less than half of the leaf bulb height, 4.9, 4.3, 4.8 and 4.6 cm, respectively. The moisture contents were 93.22%, 94.17%, 93.75% and 93.61%, protein contents were 1.51%, 1.28%, 1.39% and 1.36%, respectively. The soluble sugar content were 5.61%, 5.69%, 5.56% and 5.84%, respectively, which were 0.14-0.37 percentage point higher than that of the control variety. The crude cellulose content were 0.61%, 0.71%, 0.69% and 0.67%, respectively, which were 0.08-0.18 percentage point lower than that of the control variety. The vitamin C contents were 682.3, 687.1, 699.1 and 682.3 mg/kg, respectively, which were 48.4-65.2 mg/kg higher than the control variety. After edible quality identification, four hybrid materials of heading cabbage were selected, the leaf balls were raw (fresh) to eat, crisp texture, sweet taste. The black rot disease resistance of the composite materials was high (HR), the same as that of the control.The yield was 4.80%, 8.46%, 10.97% and 8.46% higher than that of control Tejia No. 2. [Conclusion] The four composite materials GL22-02, GL22-06, GL22-11 and GL22-13 were selected. They both had agronomic and economic characters, which can be used for production demonstration in large scale. [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cyclooctatetrathiophenes (COThs) have attracted much attention for their unique "saddle-shaped" space structure, and interesting photoelectric properties. COThs have fourteen isomers and five of them have been reported up to now. COTh-1 exhibits aggregation induced emission properties. More importantly, the mechanism stems from its "saddle-shaped" structure. However, this compound can only be dissolved in few kinds of organic solvent such as tetrahydrofuran, and the low luminescence intensity limits their applications. Porous silica nanomaterials have the advantages of large specific surface area, large pore volume, tunable particle size, good biocompatibility, environmental friendliness and surface functionality. They can be used as good candidates for composing with organic materials. In this work, COTh-1 functionalized with 3-aminopropyltriethoxysilane, then COTh-silica hybrid nanomaterial were prepared by sol-gel method. Their structures, morphology and fluorescence properties were characterized carefully with Fourier transform infrared (FT-IR), scanning electron microscope (SEM) and fluorescence spectrum, respectively. FT-IR results show that COTh-1 molecules are linked on silica via covalent bonds. The morphology of hybrid particle is uniform sphere with size of 90~100 nm. More importantly, the emission intensity of the hybrid material is enhanced unambiguously compared with that of COTh-1. The possible reason is that COTh-1 molecules are fixed within the pores of silica and results in restriction of the intramolecular motions of COTh-1 molecules. [ABSTRACT FROM AUTHOR]

Two well-defined comb-like polyester diols (GS) with C-18 side chains were synthesized by reacting glyceryl monostearate (GMS) with succinic anhydride. NCO-terminated polyurethane prepolymers (PUGS) with C-18 side chains in soft segment structure were synthesized from diphenylmethane diisocyanate (MDI), 1,4-butanediol (BDO) and GS. Then polyurethane hybrid materials (PUGS-Ti) were further prepared by mixing with nano-TiO2. The structures of GS and PUGS were characterized by 1H-NMR and FT-IR. The crystallization behavior, surface morphology and surface contact angle of the prepared PUGS and its hybrid material were characterized by DSC, WAXD, SEM, AFM and water contact angle measurements. The effects of alkyl side chain content and the amount of TiO2 on the surface properties of PUGS and its hybrid material were investigated. Results showed that the introduction of non-polar alkyl side chains into the polyurethane could significantly reduce the surface energy and improve the contact angles of water on the surface. In PUGS-Ti, the surface energy of the materials could be effectively adjusted to achieve superhydrophobicity of the surface by adjusting the content of soft segments (the number of alkyl side chains) and the amount of TiO2 in the structure. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Poly[(9,9-bis(dimethylaminoethylpropanoate)-2,7-fluorene)-co-2,7-(9,9-dioctylfluorene)] copolymers with different contents of 9,9-bis(dimethylaminoethylpropanoate)fluorene structural unit were synthesized by Suzuki coupling reaction. The nano TiO2 alcohol dispersion was prepared by solvothermal method. The PF8FDMAEA/TiO2 hybrids for electron transport layer of polymer solar cell were obtained by blending PF8FDMAEA and TiO2 alcohol dispersion. The PF8FDMAEA/TiO2 hybrid were characterized by UV-Vis absorption spectra, fluorescence emission spectra and atomic force microscopy. The performance of polymer solar cells with PF8FDMAEA/TiO2 hybrids as electron transport layers was investigated. It was found that the performance of polymer solar cells can be effectively improved by the PF8FDMAEA/TiO2 hybrids electron transporting layer. The power conversion efficiency of the polymer solar cell with PF8FDMAEA/TiO2 hybrid as the electron transport layer and structure of ITO/PEDOT:PSS/P3HT-PC61BM/(P1/20%TiO2)/Ag was 2.43%, which was 111% higher than that of polymer solar cells without the corresponding electron transporting layer. [ABSTRACT FROM AUTHOR]

An innovation experiment project was designed according to the situation of graduate student source for chemical engineering and technology discipline in agricultural colleges and universities，and combining with the professional characteristics. A bis (quinolinium) tetrachlorocobaltate (II) salt was prepared by using isoquinoline and CoCl2 • 6H2O as startingmaterials in methanol acidified with concentrated hydrochloric acid. The composition and structure of the complex were characterized by elemental analysis and single crystal X-ray diffraction. The IR，UV-Vis spectra and magnetic property were investigated. Practice showed that the experiment project has simple synthetic steps and uses raw materials easily， and contains organic chemistry， coordination chemistry， analytical chemistry， crystal chemistry and molecular magnetic chemistry and other knowledge， and has certain research and academic characteristics，is beneficial to cultivate graduate students innovation ability and scientific research capacity. [ABSTRACT FROM AUTHOR]