41 research outputs found

    Novi VP2/VP3 rekombinantni senekavirus A izoliran u sjevernoj Kini

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    Senecavirus A (SVA), previously called the Seneca Valley virus, is the only member of the genus Senecavirus within the family Picornaviridae. This virus was discovered as a serendipitous finding in 2002 and named Seneca Valley virus 001 (SVV-001). SVA is an emerging pathogen that can cause vesicular lesions and epidemic transient neonatal a sharp decline in swine. In this study, an SVA strain was isolated from a pig herd in Shandong Province in China and identified as SVA-CH-SDFX-2022. The full-length genome was 7282 nucleotides (nt) in length and contained a single open reading frame (ORF), excluding the poly (A) tails of the SVA isolates. Phylogenetic analysis showed that the isolate shares its genomic organization, resembling and sharing high nucleotide identities of 90.5% to 99.6%, with other previously reported SVA isolates. The strain was proved by in vitro characterization and the results demonstrate that the virus has robust growth ability in vitro. The recombination event of the SVA-CH-SDFX-2022 isolate was found and occurred between nts 1836 and 2710, which included the region of the VP2 (partial), and VP3 (partial) genes. It shows the importance of faster vaccine development and a better understanding of virus infection and spread because of increased infection rates and huge economic losses. This novel incursion has substantial implications for the regional control of vesicular transboundary diseases, and will be available for further study of the epidemiology of porcine SVA. Our findings provide useful data for studying SVA in pigs.Senekavirus A (SVA), prije nazivan virusom doline Seneca Valley, jedini je pripadnik roda senekavirusa u porodici Picornaviridae. Virus je slu─Źajno otkriven 2002. i nazvan virusom doline Seneca 001 (SVV-001). SVA je novi patogen koji mo┼że uzrokovati vezikularne lezije i prolaznu epidemiju novoro─Ĺene prasadi s naglim gubicima u proizvodnji. U ovom je istra┼żivanju soj SVA izoliran u populaciji svinja iz provincije Shandong u Kini i identificiran kao SVA-CHSDFX-2022. Kompletni genom izolata SVA imao je 7282 nukleotida (nt) u du┼żini i sadr┼żavao je jedan otvoreni okvir za o─Źitavanje (ORF), bez poli-A repova. Filogenetska je analiza pokazala da izolat u velikoj mjeri sadr┼żava genomsku organizaciju i nukleotidne identitete, od 90,5 % do 99,6 %, s drugim poznatim SVA izolatima. Karakterizacija virusa je pokazala da ima veliku sposobnost rasta in vitro. Prona─Ĺena je rekombinacija izolata SVA-CH-SDFX-izme─Ĺu nukleotida 1836 i 2710 ┼íto je uklju─Źilo regiju gena VP2 (parcijalno) i gena VP3 (parcijalno). Zbog visoke stope infektivnosti i golemih ekonomskih gubitaka va┼żan je br┼żi razvoj cjepiva i bolje razumijevanje zaraze. Rezultati ovog istra┼żivanja pru┼żaju korisne podatke za prou─Źavanje SVA virusa, posebno s obzirom na njegovu epidemiologiju u svinja i regionalnu prekograni─Źnu kontrolu vezikularnih bolesti

    Research of characterization of zinc ferrite, titanium dioxide and their composites

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    In this paper, zinc calcines, sulfuric acid, ferric nitrate nine-hydrate, zinc nitrate hexahydrate, titanium oxide sulfate, sodium hydroxide and ammonia water were selected as raw materials, and the methods of sulfuric acid leaching and chemical coprecipitation were used to prepare purified zinc ferrite, synthetic zinc ferrite, synthetic titanium dioxide and its composite with purified zinc ferrite. And characterized by BET, UVVis and FTIR. The results showed that: SO42- existed in purified zinc ferrite. Purified zinc ferrite, synthetic zinc ferrite and purchased had different specific surface area, pore volume and average pore size. The specific surface area of synthetic zinc ferrite decreased with the increase of calcination temperature. The three kinds of zinc ferrite had good absorption of ultraviolet light and visible light. Purchased ferric acid had the strongest absorption of UV light and synthetic zinc ferrite had the strongest absorption of visible light, and purified zinc ferrite had the absorption of UV light and visible light between the two. The specific surface area of titanium dioxide prepared by chemical coprecipitation method was greatly affected by calcination temperature. With the increase of calcination temperature, the specific surface area decreased from 123.633 to 28.036m2┬Ěg-1, and the average pore diameter was less affected by calcination temperature. For the zinc ferrite/titanium dioxide composite prepared by chemical coprecipitation method, a certain amount of purified zinc ferrite was added to facilitate the absorption of visible light by titanium dioxide

    Study on properties of zinc ferrite, titanium dioxide and their composites

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    In this paper, the methods of sulfuric acid leaching and chemical coprecipitation were used to prepare products such as purified zinc ferrite, synthetic zinc ferrite, synthetic titanium dioxide and its complex with purified zinc ferrite. The morphology and microstructure of the above samples were characterized and analyzed by XRD and SEM. The results showed that the purified zinc ferrite contained a small amount of ZnO, SiO2, Al2O3 and PbSO4. Its particle size was the largest and the crystallinity was the best, but the surface was not smooth, the particle size distribution was not uniform and there was agglomeration phenomenon. The purchased zinc ferrite had high purity, the smallest particle size and the worst crystallinity. Its surface was smooth, particle size distribution was uniform, and it was loose and porous. The synthetic zinc ferrite had high purity, smooth surface, uniform particle size distribution and obvious agglomeration. The prepared titanium dioxide had no other impurities, good crystallinity, smooth surface and certain agglomeration phenomenon. For the zinc ferrite/titanium dioxide composite, adding a small amount of purified zinc ferrite would change the crystallinity of titanium dioxide, but it had little effect on the grain size of titanium dioxide. The surface was rough, the particle size distribution was not uniform, and there was agglomeration phenomenon

    Research of characterization of zinc ferrite, titanium dioxide and their composites

    No full text
    In this paper, zinc calcines, sulfuric acid, ferric nitrate nine-hydrate, zinc nitrate hexahydrate, titanium oxide sulfate, sodium hydroxide and ammonia water were selected as raw materials, and the methods of sulfuric acid leaching and chemical coprecipitation were used to prepare purified zinc ferrite, synthetic zinc ferrite, synthetic titanium dioxide and its composite with purified zinc ferrite. And characterized by BET, UVVis and FTIR. The results showed that: SO42- existed in purified zinc ferrite. Purified zinc ferrite, synthetic zinc ferrite and purchased had different specific surface area, pore volume and average pore size. The specific surface area of synthetic zinc ferrite decreased with the increase of calcination temperature. The three kinds of zinc ferrite had good absorption of ultraviolet light and visible light. Purchased ferric acid had the strongest absorption of UV light and synthetic zinc ferrite had the strongest absorption of visible light, and purified zinc ferrite had the absorption of UV light and visible light between the two. The specific surface area of titanium dioxide prepared by chemical coprecipitation method was greatly affected by calcination temperature. With the increase of calcination temperature, the specific surface area decreased from 123.633 to 28.036m2┬Ěg-1, and the average pore diameter was less affected by calcination temperature. For the zinc ferrite/titanium dioxide composite prepared by chemical coprecipitation method, a certain amount of purified zinc ferrite was added to facilitate the absorption of visible light by titanium dioxide

    The Double Construction of Human Settlements and Regional Culture: A Review of Domestic Waterfront Spaces Research from the Perspective of Historical Inheritance

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    Urban waterfront space has important practical significance for inheriting and developing urban cultural characteristics, promoting the driving role of culture in urban development, and creating regional cultural artistic conceptions. This study comprehensively uses the methods of bibliometric visual knowledge map analysis and a qualitative reading of literature, systematically combing through the relevant research literature with the help of quantitative analysis and a qualitative perception of the literature analysis system. Through this approach, this study summarizes the stage characteristics, theoretical basis, and implications of waterfront space research from the perspective of historical inheritance. The research methods, research content, and hotspots clarified the research context of waterfront space from the perspective of historical inheritance. Based on bibliometric analysis, it is evident that research on the historical inheritance to waterfront space is primarily driven by universities and spans disciplines such as human habitat science, ecology, geography, urban planning, and architecture. Human settlement environment theory, cultural space theory, and place narrative theory together constitute the theoretical framework of the research on the historical inheritance of waterfront space. Domestic research on the historical inheritance to waterfront space in China primarily relies on traditional qualitative methods, while quantitative empirical methods have yet to become mainstream. In general, the research concerning the historical inheritance of waterfront space can be divided into three stages: first, a phase focused on the development and construction of waterfront spaces oriented towards recreation, commerce, and tourism functions; second, a stage of transforming and renewing waterfront spaces by leveraging urban development processes; and third, a stage aimed at preserving the unique cultural heritage of cities through the historical continuity of waterfront spaces. The transformation and revival of waterfront industrial heritage, the renewal and protection of waterfront historic blocks, and the protection and utilization of historical waterfront public space culture have become hot topics in the current research on the historical inheritance of waterfront space in China. This study concludes that the existing research is faced with problems such as unbalanced research areas, insufficient empirical research, and a serious separation of "pleasure" and the "ideal". Future research should focus on the system of waterfront space research as it deeply enriches the research methods, improves the research system, and provides direction and support for the historical inheritance and protection of research of China's waterfront space

    Study on Hydrometallurgical Treatment of Oxide Ores Bearing Zinc

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    As the depletion of zinc sulfide ores becomes more severe, investigations into the recovery of zinc from zinc oxide ores have aroused more interest. In this regard, acid-based hydrometallurgical treatment strategies have had great effectiveness. However, they are inadequate for low-grade zinc oxide ores. In this study, we examined the alkaline treatment of gossan for the recovery of oxide ores that bear zinc, such as siderite and limonite. Additionally, of particular note, the effects of a leaching agent, its concentration and time, temperature, liquid-to-solid ratio, as well as the agitation rate on the leaching of zinc from gossan were studied to evaluate the effects of these parameters on the kinetics of zinc dissolution. The results showed that the leaching of zinc is controlled by a single rate-controlling step with an activation energy of 4.458 kJ/mol before 120 min and 5.536 kJ/mol after 120 min, with zinc leaching efficiency less than 50% in all leachings
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