8 research outputs found

    Categorizing Security for Security Management and Information Resource Management

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    There are various definitions and dimensions of security, and there is no comprehensive taxonomy of security. The existing classifications of security are fragmented, scattered, and divergent, binging challenges in the management of security and the management of information resources about security. This research aims to study the problems of security categorization in existing knowledge organization systems, and to develop a comprehensive taxonomy of security. Through thematic analysis of the literature about security, we found that, despite the various definitions and dimensions of security, there is a common feature of security. That is, security is expressed in this pattern: subject wants to protect object against source of insecurity using certain methods. Through facet analysis, we identified four facets of security – subject/scope of security, object of protection, source of insecurity, and method of security. By nesting the four facets to reveal the content of comprehensive security terms (such as national security, human security), we can build comprehensive taxonomies of security for various user groups. This paper develops a tetra-facet model of security, and demonstrates the application of thematic analysis and facet analysis to solve a complex problem of security categorization

    An Edible and Quick-Dissolving Film from Cassia Gum and Ethyl Cellulose with Improved Moisture Barrier for Packaging Dried Vegetables

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    A quick-dissolving edible film was made from cassia gum (CG) incorporated with ethyl cellulose (EC). Mechanical results show that addition of 5% EC based on CG gave rise to the highest tensile strength (TS) of the composite film. Scanning electron microscopy revealed that excess addition of EC slightly decreased the homogeneousness of films. Fourier transform infrared spectroscopy showed that the compatibility between CG and EC was good and the incorporation of EC changed the original interaction of molecules by forming hydrogen bonds with CG. Although film light transmittance decreased, it is transparent enough for packaging. The film water vapour barrier property improved dramatically by blending CG and EC, although they showed dissolution rates over 80% in boiling water after 5 min. The dried carrot cube packaged by CG-EC films showed lower mass growth rates in 53% RH. Therefore, the film presents a potential application in packaging of dried vegetables in convenience foods

    Assembly and evolutionary analysis of the complete mitochondrial genome of Trichosanthes kirilowii, a traditional Chinese medicinal plant

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    Trichosanthes kirilowii (T. kirilowii) is a valuable plant used for both medicinal and edible purposes. It belongs to the Cucurbitaceae family. However, its phylogenetic position and relatives have been difficult to accurately determine due to the lack of mitochondrial genomic information. This limitation has been an obstacle to the potential applications of T. kirilowii in various fields. To address this issue, Illumina and Nanopore HiFi sequencing were used to assemble the mitogenome of T. kirilowii into two circular molecules with sizes of 245,700 bp and 107,049 bp, forming a unique multi-branched structure. The mitogenome contains 61 genes, including 38 protein-coding genes (PCGs), 20 tRNAs, and three rRNAs. Within the 38 PCGs of the T. kirilowii mitochondrial genome, 518 potential RNA editing sites were identified. The study also revealed the presence of 15 homologous fragments that span both the chloroplast and mitochondrial genomes. The phylogenetic analysis strongly supports that T. kirilowii belongs to the Cucurbitaceae family and is closely related to Luffa. Collinearity analysis of five Cucurbitaceae mitogenomes shows a high degree of structural variability. Interestingly, four genes, namely atp1, ccmFC, ccmFN, and matR, played significant roles in the evolution of T. kirilowii through selection pressure analysis. The comparative analysis of the T. kirilowii mitogenome not only sheds light on its functional and structural features but also provides essential information for genetic studies of the genus of Cucurbitaceae

    Negative-Pressure Cavitation Extraction of Four Main Vinca Alkaloids from <em>Catharanthus </em><em>r</em><em>oseus</em> Leaves

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    In the present study, an improved method termed negative-pressure cavitation extraction (NPCE) followed by reverse phase high-performance liquid chromatography (RP-HPLC) was developed for the extraction and quantification of vindoline (VDL), catharanthine (CTR), vincristine (VCR) and vinblastine (VLB) from <em>Catharanthus roseus </em>leaves. The optimized method employed 60-mesh particles, 80% ethanol, a negative pressure of −0.075 MPa, a solid to liquid ratio of 1:20, 30 min of extraction and three extraction cycles. Under these optimized conditions, the extraction yields of VDL, CTR, VCR and VLB are 0.5783, 0.2843, 0.018 and 0.126 mg/g DW, respectively. These extraction yields are equivalent to those from the well-known ultrasonic extraction method and higher than the yields from maceration extraction and heating reflux extraction. Our results suggest that NPCE-RP-HPLC represents an excellent alternative for the extraction and quantification of vinca alkaloids for pilot- and industrial-scale applications

    A novel and efficient ammonia leaching method for recycling waste lithium ion batteries

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    Effective recycling waste lithium-ion batteries (LIBs) are of great economic and environmental benefits. This study proposes a novel and efficient ammonia leaching method for recovering Co and Li from waste LIBs. This method yields a Co and Li leaching rate of 91.16% and 97.57%, respectively, under the optimal conditions (NH3 center dot H2O 120 g/L, NH4HCO3 75 g/L, n (Na2SO3): n (Co) = 2:1, 353 K, 240 min). Leaching kinetics also show that the speed-limiting step in this process is the interfacial chemical reaction, and the activation energy of Co and Li is 58.45 kJ mol(-1) and 50.05 kJ mol(-1), respectively. Moreover, scanning electron microscopy (SEM), energy dispersion spectrum (EDS), and x-ray diffraction (XRD) results indicate that the morphology of waste LIB powder are irregular granular and lamellar. Under the optimal condition, however, the leaching residues are scattered particles at a smaller size and the as formed MnCO3 particles are smooth with a uniform cubic structure. Besides, MnCO3 and graphite in the leaching residues can be separated and recovered. After that MnCO3 was further calcined to Mn3O4, a precursor for the production of new LIBs. Hence, a new and effective way for spent LIBs circular recycling is put forward, providing another choice for spent LIBs recycling industry. (C) 2019 Elsevier Ltd. All rights reserved.</p

    Effect of ionic liquid [MIm]HSO4 on WPCB metal-enriched scraps refined by slurry electrolysis

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    Waste printed circuit boards (WPCBs) are usually dismantled, crushed, and sorted to WPCB metal-enriched scraps, still containing an amount of non-metallic materials. This research used slurry electrolysis to refine these WPCB metal-enriched scraps and to examine if a standard ionic liquid, [MIm]HSO4, can replace H2SO4 in the system. The impact of the refinement process on metal migration and transformation is discussed in detail. The results demonstrated that metals in WPCB metal-enriched scraps could be successfully refined using slurry electrolysis, and [MIm]HSO4 can be used to replace H2SO4 in the system. When 80% of H2SO4 was replaced by [MIm]HSO4 (electrolyte of 200 mL, 30 g/L CuSO4 center dot 5H(2)O, 60 g/L NaCl, 130 g/L H2SO4, and 1.624 A for 4 h), the total metal recovery rate is 85%, and the purity, current efficiency, and particle size of cathode metal powder were 89%, 52%, and 3.77 mu m, respectively. Moreover, the microstructure of the cathode metal powder was dendritic in the H2SO4-CuSO4-NaCl slurry electrolysis system, whereas at an 80% [MIm]HSO4 substitution rate slurry electrolysis system, the cathode metal powder was irregular and accumulated as small-sized spherical particles. Thus, replacing inorganic leaching solvents with ionic liquids may provide a potential choice for the resources in WPCB metal-enriched scraps
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