Provider: - Institution: - Data provided by Europeana Collections- In the first part of this work hydrogels based on partially and completely
neutralized methacrylic acid were synthesized by ...free-radical polymerization
and crosslinking at 80°C, conventionally and in microwave field. By using
these two methods of synthesis and by varying the experimental parameters,
macroporous materials with very different characteristics, morphology, the
basic structural parameters, mechanical properties and swelling behavior,
were synthesized as demonstrated by characterizing them using Fourier
Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM),
Dynamic-mechanical analysis (DMA) and by monitoring the kinetics of
swelling. After analysis and optimization of the obtained results composite
hydrogels based on PMAA matrix with the neutralization degree of monomer of
80% and inorganic fillers, of zeolite A and ZSM-5 type at concentrations of
10-30 wt% were synthesized conventionally. The characterization of the
obtained composites was performed by FTIR, thermogravimetric (TGA) and DMA
analysis, SEM microscopy and by monitoring the swelling behavior and
dehydration at different solution pH, temperature and under effects of
ultrasonic and microwave fields. It is found that the zeolite particles are
distributed uniformly in the PMAA matrix and that the established
interactions are physical, probably hydrogen bonds. It is also found that
the composites with better mechanical properties and higher thermal
stability, sensitive to change of solution pH, while completely insensitive
to temperature changes in the investigated temperature range unless they are
exposed to ultrasound or microwave field, were synthesized. The possibility
of removing of the cationic dye basic yellow 28 (BY28) from wastewater by
sorption onto synthesized hydrogels, and the effect of the monomer
neutralization degree, presence, type and concentration of zeolite in the
hydrogels, on the efficiency of the removal of BY28 under different
experimental conditions, were investigated, as well as sorption kinetics and
isotherms. It is shown that the synthesized materials are suitable for the
removal of BY28 and that the efficiency and progress of sorption process is
affected by the type of the sorbent and the conditions applied.- U prvom delu ovog rada sintetisani su hidrogelovi na bazi delimično i potpuno
neutralisane metakrilne kiseline, radikalnom polimerizacijom i umrežavanjem
na 80°C, konvencionalno i pod dejstvom mikrotalasnog polja. Primenom ova
dva načina sinteze i variranjem eksperimentalnih parametara, sintetisani su
makroporozni materijali sa veoma različitim karakteristikama, morfologijom,
osnovnim strukturnim parametrima, mehaničkim svojstvima i ponašanjem pri
bubrenju, što je pokazano njihovim karakterisanjem primenom infracrvene
spektroskopije sa Furijeovom transformacijom (FTIR), skenirajude elektronske
mikroskopije (SEM), dinamičko-mehaničke analize (DMA) i pradenjem kinetike
bubrenja. Nakon analize i optimizacije dobijenih rezultata, konvencionalnom
radikalnom polimerizacijom su sintetisani kompozitni hidrogelovi na bazi
PMAA matrice sa stepenom neutralizacije monomera od 80% i neorganskih
punila, tipa zeolita A i ZSM-5 u koncentracijama 10-30 mas%. Karakterisanje
dobijenih kompozita izvršeno je FTIR, DMA i termogravimetrijskom analizom
(TGA), SEM mikroskopijom i praćenjem ponašanja pri bubrenju i dehidrataciji
pod uticajem različitih eksperimentalnih uslova: pH medijuma, temperature,
dejstva ultrazvučnog i mikrotalasnog polja. Utvrđeno je da je zeolit
ravnomerno raspoređen u PMAA matrici, kao i da su ostvarene interakcije
fizičke, najverovatnije vodonične veze. Utvrđeno je i da su sintetisani
kompoziti boljih mehaničkih svojstava, bržeg odziva i veće termičke
stabilnosti, pH-osetljivi, dok su u ispitivanom temperaturnom opsegu potpuno
neosetljivi na promenu temperature ukoliko nisu izloženi dejstvu utrazvučnog
ili mikrotalasnog polja. Ispitana je mogudnost uklanjanja katjonske boje
basic yellow 28 (BY28) sorpcijom iz vodenih rastvora na sintetisanim
hidrogelovima, kao i uticaj stepena neutralizacije monomera, prisustva,
vrste i koncentracije zeolita u kompozitnim hidrogelovima na uspešnost
uklanjanja navedene boje, pod različitim eksperimentalnim uslovima, kao i
kinetika sorpcije i adsorpcione izoterme. Pokazano je da su sintetisani
materijali pogodni za uklanjanje BY28 i da su uspešnost i tok procesa
sorpcije uslovljeni vrstom sorbenta i primenjenim uslovima.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Clays are frequently proposed for the addition to dairy cattle diets to reduce the transfer of mycotoxins in milk. This study examined the effect of the addition of clinoptilolite to the diet of ...lactating dairy cows on milk production and milk composition. Thirty-two lactating Holstein cows (average lactation length: 142 d) were blocked according to milk production, parity and days of lactation for assignment to one of two dietary treatments: control diet; control diet + clinoptilolite, 200g/d. The control diet was based on corn and alfalfa silages, hay and concentrates, and did not contain aflatoxins above the safe level. The experimental period lasted 76 days. The clinoptilolite supplementation did not affect milk yield and milk composition other than urea contents. The urea level in milk was negatively affected by clinoptilolite addition (control group 29.7 mg/100 ml vs clinoptilolite group 31.3 mg/100 ml). The dietary addition of clinoptilolite did not change pH, ammonia content and VFA molar percentages in the rumen. No dietary effect on mineral contents of blood plasma (Na, K, Zn, and Ca) was observed. In case of clinoptilolite use in dairy cattle feeding, scarce negative effect on milk production and quality are expected
To evaluate the effects of clinoptilolite on piglet and heavy pig production two separated trials have been performed. In the first trial 40 pigs of the initial body weight of 55 kg were used. ...Animals were homogeneously allocated to two groups: a control group traditionally fed and a clinoptilolite group in which feed contained the additive at 2%. Pigs were slaughtered at about 160 kg body weight. Blood samples were taken to determine blood urea nitrogen (BUN). In the second trial a total of 116 piglets from 12 litters was used. Six litters were fed from the 7
th
day of life a diet containing clinoptilolite at 2%. According to the dietary treatment of the suckling period, 84 weaned piglets were homogeneously allocated to two groups fed up to 33 kg body weight a diet containing or not clinoptilolite at 2%. In both trials daily weight gain, feed intake and pigs' health were regularly recorded. The dietary inclusion of clinoptilolite at 2% did not resulted in any modification either of growing performances or of uraemia. Piglets on clinoptilolite diet showed a significant (P<0.05) improvement of faecal dry matter content. At slaughtering the dietary inclusion of clinoptilolite resulted in a trend towards an improvement of lean cuts yield and in a significant increase (P<0.05) of the ratio between lean and fat cuts. From our data it is suggested that clinoptilolite does not impair pig growing performances, determines a higher dry matter content of piglet faeces and improves carcass quality of heavy pigs with particular regard to lean cuts yield and lean to fat cuts ratio.
U ovome radu sažeta su istraživanja i vlastita iskustva o mogućnosti iskorištavanja svojstava prirodnog zeolita kod završnog stupnja obrade vode za uklanjanje tragova metalnih iona kao kroma, srebra ...i arsena. Arsen prisutan u prirodnim vodama je genetskog podrijetla zbog procesa razlaganja minerala kojim prolaze podzemne vode. Ostali ispitivani metalni ioni su uglavnom antropogenog podrijetla zbog utjecaja kemijske, tekstilne i metalurške industrije. Rezultati istraživanja pokazali su da je efikasnost uklanjanja arsenovih iona na željezom modificiranim zeolitima za niže koncentracijsko područje do 100 %, kromovih iona za koncentracijsko područje 0,5-20 mg/L od 40 do 60 % ovisno o modifikaciji zeolita, a srebrovih iona za koncentracijsko područje 5-120 mg/L od 55 do 70 % ovisno o nalazištu prirodnog zeolita.
The effects of adding 2% of natural zeolite, containing a high percentage of clinoptilolite, to the diet of piglets were evaluated by monitoring growing performance and plasma parameters. The diet ...was also deprived of colistine, an antibiotic usually added to piglet diets at subtherapeutic levels to prevent gastrointestinal pathology. Sixty-four piglets, weaned at 7.9 kg live weight, were divided in 2 groups of 32 each. The control group was given commercial piglet feedstuffs; for the treated group, 98% of the same feed, deprived of colistine, was used, with the addition of 2% of a natural zeolite. The trial lasted 36 days. The piglets fed the control diet exhibited greater weight in the first three weeks, after which the differences were not significant. The average daily weight gain in the first week was higher in the control group (+37%; P0.01), whereas at the end of the trial no differences were found. The feed intake did not show significant differences between groups and, as a result, the feed efficiency at the end of the trial was higher in the control group (532 vs. 491; P0.05). The plasmatic nitrogen parameters did not show significant differences between groups. Only in the first three weeks post-weaning the group fed the diet containing colistine showed better ADG, subsequently it can be eliminated and clinoptilolite could favour growth
Strawberry cultivation is one of the most important factors in the economic development of the province of Huelva. The great surface in cultivation (9,000 ha in 1999), together with an excessive use ...of nitrogen-based fertilizers, has polluted the aquifer which supplies water for both farming and the surrounding villages. In order to find solutions to this problem, different experiences have been carried out with zeolites. Experiences were performed in the unsatured zone of a detritic aquifer, determining the descent velocity of the soil solution with and without zeolites. The main conclusion of this study is that the presence of a zeolitic substratum in sandy soils exerts a cushioning effect in the descent of nutrients towards the saturated zone, as well as a delay in their movement through the reticular zone
La coltivazione della fragola e' uno dei piu' importanti fattori di sviluppo economico nella provincia di Huelva. La grande superficie coltivata (9.000 ha nel 1999), unitamente a un impiego eccessivo di fertilizzanti a base di azoto, ha determinato l'inquinamento della falda che fornisce l'acqua per impieghi agricoli e per i villaggi della zona. Allo scopo di trovare una soluzione a questo problema, sono state effettuate esperienze diverse con le zeoliti. Le esperienze sono state condotte nella zona non satura di una falda detritica, determinando la velocita' di discesa della soluzione del terreno con e senza zeoliti. La conclusione principale di questo studio e' che la presenza di un substrato zeolitico nei terreni sabbiosi esercita un effetto cuscinetto sulla discesa degli elementi nutritivi verso la zona satura e ne rallenta i movimenti nell'ambito della zona reticolare
Prirodni zeoliti su kristali aluminijskih silikata s jedinstvenim apsorpcijskim i katalitičkim svojstvima. U medicini im se pripisuju antitumorska, antialergijska, antiseptička, antireumatska i druga ...svojstva, te snažan utjecaj na poboljšanje cirkulacije. Dodatak nanočestica zeolita u različitim fazama predobrade i obrade tekstila novost je u oplemenjivanju tekstila za multifunkcijske učinke zaštite. Zeoliti doprinose zaštiti od UV zračenja jer raspršuju UV zračenje, za razlilku od drugih sredstava koja ga apsorbiraju i tako sprječavaju njihovu transmisiju. Dodani azalidima u oplemenjivanju tekstila, zeoliti pojačavaju njihovo učinkovito antimikrobno djelovanje. U radu je pamučno pletivo mercerizirano i bijeljeno uz dodatak nanočestica aktiviranog zeolita, klinoptilolita, te obrađeno azalidom u svrhu postizanja multifunkcijske zaštite. Klinoptilolit je dodan u kupelj za predobradu, obradu i modifikaciju pamuka. Svojstva obrađenog pamuka određena su međunarodnim normama (EN, ISO, AS/NZS, AATCC).
Marrows and melons on zeolite, more yield and less fertilization [Cucurbita pepo L.; Cucumis melo L.; Lombardy Passaglia, E. (Modena and Reggio Emilia Univ. (Italy). Dipartimento di Scienze della Terra); Bellarmi, T. (Modena and Reggio Emilia Univ. (Italy). Dipartimento di Scienze della Terra); Guidetti, A. (Istituto Tecnico Agrario Statale P.A. Strozzi, Palidano, Mantua (Italy)) ...
L'Informatore agrario,
(23-29 Dec 2005), Letnik:
61, Številka:
50
Journal Article
Antibiotic growth promoter (AGP) withdrawal in swine feeding Gaidella, L. (Azienda Sanitària Locale (ASL), Mantua (Italy)); Cantoni, C. (Milan Univ. (Italy). Dipartimento di Scienze e Tecnologie Veterinarie per la Sicurezza Alimentare)
Atti della Società Italiana di Patologia ed Allevamento dei Suini (Italy),
(2005), Letnik:
31
Conference Proceeding
The AA discuss about the EU ban of antibiotic growth promoters in swine feeding and the concerning problems from January 2006
Gli AA elencano le principali alternative connesse con la sospensione ...dell'uso degli antibiotici auxinici nell'allevamento suino dal 1 gennaio 2006
Priprava amorfnih alumosilikatnih prekursora definiranih svojstava bitan je čimbenik za studij nukleacije i kristalnog rasta zeolita tijekom njihovih termalnih i hidrotermalnih transformacija u ...zeolite i specijalne keramičke materijale. U ovom radu je prikazan učinak jakih mehaničkih sila na strukturna svojstva zeolita A i zeolita A u kojem su Na+ ioni djelomično ili potpuno zamijenjeni različitim kationima (Li+, K+, Cs+, NH4+).
Prikazan je utjecaj različitih kationa na mehaničku i termičku stabilnost zeolitne građe i dobivanje amorfnih prekursora kao i njihove termičke transformacije u nezeolitne kristalne faze.
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