123 research outputs found

    Precipitation of some slightly soluble salts using emulsion liquid membranes

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    Emulsion liquid membranes were used for precipitation of different sparingly soluble salts: calcium oxalate, copper oxalate, nickel oxalate, cobalt oxalate, lanthanum oxalate, calcium phosphate, cobalt phosphate, copper phosphate, lanthanum phosphate, barium sulphate, strontium sulphate and calcium sulphate. For the transport of a desired cation or anion from the feed into the stripping solution, where the precipitation occurred, one of the commercial ligands (bis(2-ethylhexyl)phosphoric acid, D2EHPA; 2-hydroxy-5-nonyl-acetophenone oxime, LIX 84; trioctylamine, ALAMIN 336) dissolved in kerosene, was used as a carrier. The precipitates obtained were characterized by means of transmission electron microscopy, X-ray diffractometry, FT-IR spectroscopy and thermogravimetry. The effect of the transport mechanism on the properties of salt precipitated was studied on calcium and copper oxalate model systems. It was found that copper oxalate hemihydrate and calcium oxalate monohydrate precipitated regardless of whether oxalic acid or a cation (calcium or copper) was transported into the stripping solution. It was also found that the particles of the precipitate were smaller when oxalic acid was transported

    Primjena GIS-a u penjanju

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    ZavrÅ”ni rad bavi se projektiranjem i implementiranjem GIS-a u aplikaciju za pametne mobilne telefone. Opisan je proces sustava za izradu aplikacije, principi rada pametnih telefona i geoinformacijskog sustava te su na temelju proučene i analizirane literature opisani postupci koje treba odraditi kako bi se projekt realizirao. Prvi dio zavrÅ”nog rada sastoji se od uvoda u rad, u drugom dijelu opisuju se pametni telefoni i Android operacijski sustavi, u trećem dijelu opisuju se GPS odaÅ”iljači i prijamnici, programski jezici i baze podataka, dok je konkretnija procedura izrade aplikacije za primjenu GIS-a u penjanju opisana u četvrtom dijelu zavrÅ”nog rada

    Challenges of ecological agriculture in the European union from administrations' and farmers' perspective

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    Tijekom posljednjeg desetljeća uočen je porast interesa poljoprivrednika za bavljenjem ekoloÅ”kom proizvodnjom Å”to pokazuje da je globalni trend prelaska na ekoloÅ”ku poljoprivredu zahvatio i Republiku Hrvatsku. U promatranom razdoblju (2009.-2016.) na području Bjelovarsko-bilogorske županije (BBŽ), zabilježen je znatan porast u broju ekoloÅ”kih proizvođača kao i u povrÅ”inama pod ekoloÅ”kom proizvodnjom. Ciljevi rada su utvrditi promjene u broju ekoloÅ”kih proizvođača na razini Hrvatske, utvrditi strukturu povrÅ”ina pod ekoloÅ”kom proizvodnjom (biljna i stočarska proizvodnja) na razini Hrvatske, te na primjeru BBŽ-a identificirati promjene u politikama koje reguliraju ekoloÅ”ku proizvodnju prije i nakon pristupanja EU. Istraživanje je obuhvatilo razdoblje od 2009. do 2016. godine. Uz statističke podatke Eurostata, Ministarstva poljoprivrede i Državnog zavoda za statistiku i analizu sadržaja pravilnika o ekoloÅ”koj proizvodnji, za potrebe rada proveo se polustrukturirani intervju s poljoprivrednicima i djelatnicima raznih službi na području BBŽ-a.Over the past decade, an increasing interest of farmers has been observed in ecological production, which indicates that the global trend of transition to ecological agriculture has also affected the Republic of Croatia. In the research period on the observed area of Bjelovar-Bilogora County (BBZ), there has been a significant increase in the number of organic producers as well as in organic production areas. The aims of this paper are to identify changes in the number of organic producers in Croatia, to determine the structure of organic production area (crop and livestock production) in Croatia, and also to identify BBZ's changes in policies that regulate organic production before and after EU accession. The research covered the period from 2009. to 2016. Along with the Eurostat, Ministry of Agriculture and Croatian Bureau of Statistics data and the content analysis of the Organic Production Act, a semi-structured interview with farmers and employees of various services in the Bjelovar-Bilogora County was conducted

    Abbreviations in Croatian Standard Language in the past and today

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    U radu se prikazuje kako se krate riječi u hrvatskome standardnome jeziku. Pruža se i kraći povijesni pregled kraćenja riječi. u 20. stoljeću prema normativnim priručnicima: pravopisima, gramatikama, rječnicima i jezičnim savjetnicima. Iznose se pravila kraćenja riječi, odnosno stvaranja kratica i pokrata. Detaljno se opisuju pravopisna, gramatička i tvorbena svojstva kratica i pokrata te izgovor pokrata. Istraživanje prikazuje kako se kratice i pokrate danas upotrebljavaju u trima funkcionalnim stilovima hrvatskoga standardnoga jezika: publicistički, administrativni i znanstveni. Može se zaključiti da je suvremena komunikacija nemoguća bez upotrebe kratica i pokrata te da su pravila propisana u hrvatskim standardnim normativnim priručnicima, ponajviÅ”e u pravopisima i jezičnim savjetnicima. Pravila se prema istraživanju većinom dosljedno poÅ”tuju, a pogreÅ”ke su vezane za izostavljanje bjeline nakon točke kod pisanja kratica te nepravilna sklonidba pokrata stranoga podrijetla.The paper presents how words are shortened in Croatian standard language. There is also a brief historical review of shortening words in the 20th century according to normative manuals: grammar books, dictionaries and language consultants. The paper shows the rules of creating abbreviations and acronyms and the pronunciation of acronyms.The research shows how abbreviation and acronyms are used today through three functional styles of the Croatian standard language: publicist, administrative and scientific style. It concluded that contemporary communication is impossible without the use of abbreviations and acronyms and that the rules are prescribed in Croatian standard normative manuals, most notably in grammar books and language consultants. Rules, based on the research, are mostly respected, and mistakes are related to the omission of whiteness after the point in writing the abbreviations and the wrong declination of the acronyms of foreign origin

    Primjena GIS-a u penjanju

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    ZavrÅ”ni rad bavi se projektiranjem i implementiranjem GIS-a u aplikaciju za pametne mobilne telefone. Opisan je proces sustava za izradu aplikacije, principi rada pametnih telefona i geoinformacijskog sustava te su na temelju proučene i analizirane literature opisani postupci koje treba odraditi kako bi se projekt realizirao. Prvi dio zavrÅ”nog rada sastoji se od uvoda u rad, u drugom dijelu opisuju se pametni telefoni i Android operacijski sustavi, u trećem dijelu opisuju se GPS odaÅ”iljači i prijamnici, programski jezici i baze podataka, dok je konkretnija procedura izrade aplikacije za primjenu GIS-a u penjanju opisana u četvrtom dijelu zavrÅ”nog rada

    Formation and Morphology of Struvite and Newberyite in Aqueous Solutions at 25 and 37 Ā°C

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    The influence of the initial reactant concentrations (ci(Mg)tot = 5.0 x 10ā€“6 to 5.0 x 10ā€“1 mol dmā€“3, ci(P)tot = ci(NH4)tot = 1.0 x 10ā€“3 to 5.0 x 10ā€“1 mol dmā€“3) and temperature (25 and 37 Ā°C) on the composition and morphology of the precipitates formed in the system MgCl2-NH4H2PO4-NaOH-H2O at initial pHi = 7.40 has been investigated. Precipitation diagrams are presented showing the concentration regions within which different morphologies of solid phase have been formed. The solid phases aged for 24 hours were characterized by means of optical microscopy, FT-IR spectrophotometry, X-ray diffractometry and thermogravimetry. It was found that struvite was a predominant phase formed within the concentration region examined and newberyite was obtained only in the region where pH24h < 6.5. The influence of the initial pH on the formation and transformation of these two compounds were studied in the region 5.0 pHi ā‰¤ 9.0 and the results are discussed

    Proizvodnja kućiÅ”ta rasvjetnog tijela tipa Hyper

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    Rad ne sadrži sažetak

    Abbreviations in Croatian Standard Language in the past and today

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    U radu se prikazuje kako se krate riječi u hrvatskome standardnome jeziku. Pruža se i kraći povijesni pregled kraćenja riječi. u 20. stoljeću prema normativnim priručnicima: pravopisima, gramatikama, rječnicima i jezičnim savjetnicima. Iznose se pravila kraćenja riječi, odnosno stvaranja kratica i pokrata. Detaljno se opisuju pravopisna, gramatička i tvorbena svojstva kratica i pokrata te izgovor pokrata. Istraživanje prikazuje kako se kratice i pokrate danas upotrebljavaju u trima funkcionalnim stilovima hrvatskoga standardnoga jezika: publicistički, administrativni i znanstveni. Može se zaključiti da je suvremena komunikacija nemoguća bez upotrebe kratica i pokrata te da su pravila propisana u hrvatskim standardnim normativnim priručnicima, ponajviÅ”e u pravopisima i jezičnim savjetnicima. Pravila se prema istraživanju većinom dosljedno poÅ”tuju, a pogreÅ”ke su vezane za izostavljanje bjeline nakon točke kod pisanja kratica te nepravilna sklonidba pokrata stranoga podrijetla.The paper presents how words are shortened in Croatian standard language. There is also a brief historical review of shortening words in the 20th century according to normative manuals: grammar books, dictionaries and language consultants. The paper shows the rules of creating abbreviations and acronyms and the pronunciation of acronyms.The research shows how abbreviation and acronyms are used today through three functional styles of the Croatian standard language: publicist, administrative and scientific style. It concluded that contemporary communication is impossible without the use of abbreviations and acronyms and that the rules are prescribed in Croatian standard normative manuals, most notably in grammar books and language consultants. Rules, based on the research, are mostly respected, and mistakes are related to the omission of whiteness after the point in writing the abbreviations and the wrong declination of the acronyms of foreign origin

    Factors influencing the formation of calcium oxalate hydrates in vitro

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    Općenito uzevÅ”i, na proces taloženja iz prezasićenih otopina utječu fizikalno-kemijska svojstva tih otopina, hidrodinamički čimbenici piocesi mijeÅ”anja reaktanata i taložnoga sustava, kao i prisutnost topljivih nečistoća u sustavu. Zbog važnosti procesa taloženja u brojnim područjima znanosti i tehnike, od izuzetnoga su značaja temeljna istraživanja tih procesa kao i međudjelovanja koja dovode do stvaranja taloga. Obzirom na činjenicu da su kalcijevi oksalati glavni sastojci mokraćnih kamenaca, njihovo izučavanje, kao i izučavanje fizikalno-kemijskih čimbenika koji dovode do njihovoga nastajanja jesu od posebnog značaja u području patoloÅ”ke mineralizacije. Kalcijevi oksalati tvore tri hidratna oblika od kojih je monohidrat (COM) termodinamički stabilan, dok su dihidrat (COD) i trihidrat (COT) metastabilni. Rezultate istraživanja utjecaja brojnih termodinamičkih i kinetičkih čimbenika, kao i potencijalnih inhibitora na nastajanje i transformaciju kalcijevih oksalata pri različitim eksperimentalnim uvjetima, prikazane u ovom pregledu, sadaÅ”nji su autori ostvarili i objavili tijekom 1980-ih.Precipitation from supersaturated solutions is in general affected by the physical chemical properties ot the solution, by the hydrodynamics of the system, i.e., by the processes of mixing reactants and stirring the system, as well as by soluble impurities present in the system. Therefore, such a knowledge should be considered in a number of areas where precipitation plays an important role. Since calcium oxalates have been found to be a major crystal constituent of urinary stones, their investigations, as well as investigations of physical chemical conditions relevant for their formation are of particular importance for fundamental research in the field of patological mineralization. Calcium oxalate forms three hydrates. These three hydrates are the thermodynamically stable monohydrate (COM) and the metastable modifications, dihydrate (COD) and trihydrate (COT). The results on investigations of the influence of a number of thermodynamic and kinetic factors, as well as the potential inhibitors, on the hydrate formation and transformation under different experimental conditions had been obtained and published by the present authors during 1980th
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