Impact of differnet inorganic phosphorus sourecs in broilers feed on production performances and bone mineralization

Fosfor je mineral od esencijalnog značaja, budući da je uključen u većinu metaboličkih funkcija u organizmu. Biološka iskoristivost ovog minerala iz biljnih hraniva je ograničena, usled toga što je u njima fosfor prisutan u formi fitinske kiseline i njenih soli – fitata. Stoga je neophodno uključivanje neorganskih izvora fosfora u obrok za živinu, u cilju obezbeđivanja optimalnih količina fosfora dostupnog organizmu za apsorpciju. Brojni su faktori koji utiču na stepen apsorpcije fosfora iz kompletne smeše (koncentracija ukupnog fosfora u hrani, odnos fitinske i nefitinske komponente, koncentracija kalcijuma u smeši, odnos kalcijuma i fosfora, prisustvo vitamina D, uzrast i genotip jedinki...). Cilj ovde izvedenog ogleda je da se ispita uticaj ishrane brojlera obrocima sa i bez dodatog monokalcijum fosfata, kao izvora neorganskog fosfora u hrani, na proizvodne rezultate, iskoristivost fosfora i zdravstveno stanje brojlera, sa posebnim osvrtom na stepen mineralizacije koštanog sistema. U ogled je uključeno 300 jednodevne piladi i, to tri grupe po 100 jedinki ujednačnih po polu i telesnoj masi. Ogledni period podeljen je u tri faze (1 -21. dan, 22 – 35. dan i 36 – 42. dan), tokom kojih se ishrana piladi razlikovala samo u pogledu sadržaja i porekla mineralnih hraniva. Kontrolna grupa piladi hranjena je hranom bez dodatog mineralnog hraniva, dok je u hranu ogledne grupe O – I uključen monokalcijum fosfat proizvođača „Elixir Feed“ DOO iz Šapca, a u hranu ogledne grupe O – II uvozni monokalcijum fosfat. Tokom ogleda praćeni su proizvodni rezultati (telesna masa, ukupni i dnevni prirast, konzumacija hrane, konverzija hrane). Po 10 jedinki iz svake ogledne grupe prebačeno je 11. i 25. dana u metaboličke kaveze, da bi se obezbedilo uzimanje uzoraka fecesa u cilju ispitivanja prividne i prave svarljivosti fosfora...Phosphorus (P) is an essential mineral for animals, due to its role in majority of metabolic functions. Bioavailability of P from plant feed is limited, because P in plants is present in the form of phytic acid or its salts - phytates. Thus, the inclusion of inorganic phosphorus sources in poultry feed is necessary in order to ensure optimum amounts of available phosphorus. Numerous factors affect the level of absorption of the phosphorus from the complete mixture (concentration of total phosphorus in the diet, ratio of phytinine and non-phytin component, concentration of calcium in the mixture, calcium and phosphorus ratio, vitamin D, age and genotype...). The aim of this trial was to examine the impact of feeding broilers with and without addition of monocalcium phosphate in complete feed mixture, on production performances, phosphorus digestibility and health condition of broilers, with a special focus on bone mineralization. The trial included 300 one-day-old broilers, both sexes, which were randomly divided into three groups – by one hundred birds each. The experiment lasted 42 days, and was divided into three periods (days 1 – 21 for starter, days 22 – 35 for grower, and days 36 – 42 for finisher). One group of broilers (control group) was fed diet without the addition of MCP (basal diet). The other two groups of broilers received diets with the addition of two different kinds of MCP (the one was originating from “Balakovo Mineral Fertilizers”, Balakovo, Russia (O – II experimental group), and the other one was produced by “Elixir Feed” DOO, Šabac, Serbia (O – I experimental group)). The production results (average body weight, average daily gain, feed intake and feed to gain ratio) were monitored during the trial. At day 11 and day 25, by 10 birds from each group were placed into the individual balance cages, in order to provide the collection of feces during five consecutive days..

Histamin u ribi dostupnoj na tržištu Srbije u 2018. godini

Histamine is a biogen amin, which is formed by decarboxylation of the histidine amino acid, under the action of the L-histidine-decarboxylase enzyme. High level of free histidine in fish meat, bacterial histidin decarboxylase activity and high temperature of storage elevate the level of histamine. Among the most important factors that can affect the level of histamine in fish meat are the type of fish and the method of its preservation. In order to determine this dependence, 1030 samples of frozen fish (tuna, mackerel, sardines and sprat) and 167 samples of canned fish (tuna, sardines and mackerel) were monitored for histamine content by ELISA method. It was determined a lower concentration of histamine in frozen fish (from 5.71 mg/kg to 18.03 mg/kg) compared to canned fish (from 15.03 mg/kg to 110.6 mg/kg). The highest histamine concentrations were found in the mackerel samples, regardless of the preservation method (110.6 mg/kg in canned mackerel and 18.03 mg/kg in frozen mackerel), which were significantly higher compared to the histamine levels found in cans of tuna and sardines (p ˂0.0001). Of the total number of samples, three samples (two samples of canned sardines and one sample of canned mackerel) were declared unsafe for human health. In most of the analyzed samples, the level of determined histamine was relatively low, which confirms adequate implementation of control protocols and efficant surveillance of products placed on the Serbian market.Histamin je bioaktivni amin, koji nastaje u reakciji dekarboksilacije aminokiseline histidina, pod dejstvom enzima Lhistidin dekarboksilaze. Visok nivo slobodnog histidina u mesu ribe, aktivnost enzim produkujućih bakterija i visoke temperature skladištenja deluju predisponirajuće na sintezu histamina. Među najznačajnije faktore koji utiču na koncentraciju histamina u mesu ribe jesu vrsta ribe i metod njenog konzervisanja. U cilju utvrđivanja ove zavisnosti, uzorci zamrznute ribe (tune, skuše, sardine i papaline) i ribe u konzervi (tune, sardine i skuše) su analizirani ELISA metodom. Utvrđene su niže koncentracije histamina u uzorcima zamrznute ribe (od 5.71 mg/kg do 18.03 mg/kg) u poređenju sa konzervama od ribe (od 15.03 mg/kg do 110.6 mg/kg). Najviše koncentracije histamina su ustanovljene u uzorcima skuše, bez obzira na metod konzervisanja (110.6 mg/kg u konzervama od skuše i 18.03 mg/kg u zamrznutoj skuši), koje su bile i statistički značajno veće u odnosu na konzerve tune i konzerve sardine (p ˂0.0001). Od ukupnog broja uzoraka, samo tri uzorka (dva uzorka sardine u konzervi i jedan uzorak skuše u konzervi) su proglašeni nebezbednim za zdravlje ljudi. U najvećem broju ispitanih uzoraka izmerene su relativno niske koncentracije histamina, što ukazuje na adekvatno sprovođenje kontrole i nadzora nad proizvodima koji se plasiraju u promet na srpskom tržištu

The influence of thermodynamic parameters on alkaline activators of geopolymers and the structure of geopolymers

Thermodynamic parameters (densities, viscosities, speed of sound, and refractive index) of four series of alkaline activators were determined over the temperature range from 15 to 60 degrees C for the process of geopolymerization. Mixtures of Na2SiO3 and NaOH of different molar concentrations ( from 2M to 8M with step 2) were used as an alkaline activator. The sample with the highest NaOH concentration also shows the highest values of all thermodynamic parameters. Metakaolin, obtained by calcination of kaolin at 750 degrees C, was used as the starting material. The samples were characterized by X-ray diffraction (XRD), FTIR and Raman spectroscopy, Scanning Electron Microscopy (SEM), and Energy-Dispersive X-Ray (EDX) Spectroscopy. Results of FTIR analysis correlated with results of Raman Spectroscopy. Due to the polymerization process, the changes in the phonon spectrum were confirmed. The different concentrations of activators do not notably change the Si/Al ratio

Effect of Alkaline Activator Properties on Structure of Metakaolin-Based Geopolymer Samples

Considering geopolymers as inorganic polymers, they are actually amorphous network of interlinked silicate and aluminate groups, so they could be prospective ceramic precursors for materials with defined dimensions obtained by casting and firing, but not from powder processing. In this research, the starting material is metakaolin, which was obtained by calcining domes tic kaolinite clay. Initially, four series of alkaline activators of NaOH and sodium silicate have been used. Activators present the mixtures of Na2SiO3 and solutions of NaOH, of different molarities 2M, 4M, 6M and 8M. The prepared geopolymer slurries were cast into the designated near shape at room temperature and after that at 60oC. In fact, the post-synthesis curing process (28 days) has an important role in the obtaining good characteristics of geopolymers. Densities, viscosities and refractive index of alkaline activators were determined over the temperature range 15-60oC of process of geopolymerizations. Based on the obtained results of investigated parameters have been selected to predict the properties of materials. All geopolymer samples were characterized by XRD, FTIR, SEM/EDS analysis and Raman spectroscopy providing complementary and valuable information of the investigated materials. This route of ceramics production has advantages associated with producing an environmental friendly, energy saving, clean new technology of geopolymer materials

Антикорозиона активност деривата шифових база 2-тиохидантоина за меки челик у 0,5 m hcl

Several 2-thiohydаntоin–Shiff base derivatives were prepared as ecofriendly corrosion inhibitors for mild steel in acid environment. Their anticorrosion properties were studied on mild steel in 0.5 M HCl solution as corrosion electrolyte by using usuаl grаvimеtriс and different elесtrосhemicаl techniques (wеight lоss mеаsurеmеnt, pоtеntiоdynаmiс pоlаrizаtiоn and pоtеntiоstаtiс еlесtrосhеmicаl impеdаnсе sресtrоscору). Mild steel surface was characterized using two analytical techniques, scanning electron microscopy for surface morphology and elemental composition and atomic force microscopy. The study has shown that the inhibiting action of these environmentally benign inhibitors synthesized from inexpensive commercially available starting materials could be attributed to adsorption on the metal surface.Неколико деривата Шифових база 2-тиохидантоина су направљени као еколошки прихватљиви инхибитори корозије меког челика у киселој средини. Њихова антикорозиона својства су испитана на меком челику у 0,5 M раствору HCl као корозионом електролиту, користећи уобичајене гравиметријске и различите електрохемијске технике (мерење губитка масе, потенциодинамичка поларизација, потенциостатска спектроскопија електрохемијске импеданције). Површина меког челика је окарактерисана двема аналитичким техникама, скенирајућом електронском микроскопијом за морфологију површине и елементарни састав и микроскопијом атомске силе. Студија је показала да се инхибиторно деловање ових еколошки бенигних инхибитора, синтетисаних из јефтиних комерцијално доступних полазних материјала, може приписати адсорпцији инхибитора на површини меког челика

The influence of thermodynamic parameters of the alkaline activator on the mechanical properties of geopolymers

In order to optimize process of geopolymerization, the investigation of thermodynamic parameters of alkali activators are important. The aim of this research was to investigate the influence of thermodynamic parameters (density, viscosity, refractive index and sound velocity) of alkaline activators on mechanical properties (compressive strength and hardness) of synthesized geopolymer samples. Geopolymers were synthetized by alkaline activation of metakaolin, having the density 2.524 g/cm3, using the activators at elevated temperature of 60 oC for two days. Based on the obtained results thermodynamic properties has been selected to predict the properties of materials. Four series of alkaline activators have been used. Activators remarked as AA1, AA2, AA3 and AA4 present the mixtures of Na2SiO3 and solutions of NaOH, of different molarities 2M, 4M, 6M and 8M respectively. The volume ratio of Na2SiO3 and aqueous solution of NaOH was the same for all samples. Densities, viscosities and refractive indices of alkaline activators were determined over the temperature range 15-60 oC of process of geopolymerizations. The values of density, viscosity and refractive index decrease with temperature increase over the investigated temperature range. Increasing molarity of alkali activator solutions, the sound velocity of activators is changed. For sample AA2 the values of sound velocity rises from room temperature to 45 °C and then begins to decrease while for the sample AA3 sound velocity grows until 30 °C and then starts to decrease with further increasing of temperature. Four series of geopolymer samples GP1 to GP4 were synthesiyed using the constant ratio of solid and liquid phase. FTIR, XRD, SEM-EDS methods were used for physicochemical further characterization of geopolymer samples

Synthesis and characterization of Brushite-metakaolin-based geopolymer materials

In a field of green chemistry, environmental protection and ecological conservation of the environment there are ways to come up with new and more advanced materials using on the one hand natural, recyceled or waste materials and on the other hand syntethic materials obtained by using green chemistry synthesis procedures. The aim of this paper was to synthesize and characterize Brushite-metakaolin-based geopolymer materials and to examine the possibility of using these materials in the fields of construction, cement industry, as well as in environmental protection as potential adsorbents. Initial materials which were used for geopolymer synthesis was Brushite (CaHPO4·2H2O) which was obtained by solutionprecipitation reaction form acetate solutions and Kaolinite clay from Rudovci deposit (Serbia). The obtained mixture powders were dissolved in a strong alcaline solution with addiction of water glass. Produced geopolymers was cast into mods and preserved for 28 days. The starting materials and the synthesized Brushite-metakaolin-based geopolymer material were examined using XRPD, FTIR SEM-EDS methods. The contact angle measurements were made to test hydrophilic and wettable properties of synthesized material

The Effect of Alkaline Activator Molarity and Aging Time on the Structure of Inorganic Polymer

The goal of this research was to produce an environmental friendly, energy saving inorganic polymer using a metakaolin as a precursor. The clean technology which conserve the natural environment was employed for the production of these materials. The used kaolinite is clay obtained from Rudovci, Lazarevac, Serbia. Physicochemical properties of kaolin were investigated in previous work by Nenadović et al. [1]. Metakaolin (MK) was prepared by calcining kaolinite at 750 °C for 1 h. The influence of alkali activation, i.e. different concentration of NaOH as a component of alkali activator mixture on the process of polymerization of metakaolin is investigated. The alkaline solution was prepared from sodium silicate and 2M, 4M, 6M and 8 M NaOH (analytical grade) (volume ratio Na2SiO3/NaOH = 1.6). The inorganic polymer (IP) samples were formed from metakaolin and the four different alkaline solution (solid/liquid ratio was about 1), which were mixed for 15 min and then left at room temperature for one day. Finally, the mixture was kept in a sample drying oven for 2 days at 60 °C. Process of aging time of inorganic polymer samples at 7th, 14th, 21st and 28th days is followed by some analytical methods (XRD, FTIR). X-ray diffraction (XRD) and Fourier transformation infrared spectroscopy (FTIR) were used for characterization of metakaolin and metakaolin based inorganic polymers. After 28th days when the aging time were finished, on the surface of the samples were used scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). XRD analysis almost of all inorganic polymer samples revealed their amorphouslike structure with the position of an amorphous halo in the range 18°-32°, which indicates short range ordering of the reference sample with crystalline admixture of SiO2 (α-quartz, ICSD 89). The FTIR spectra of all samples shows a strong peak at ∼1000 cm−1 which is associated with Si–O–Si asymmetric stretching vibrations and is the finger print of the geopolymerization [2,3]. The FT-IR results show a shift of the Si-O or Si-O-X bands as the molarity of activator increasing during polymerization process, where X can be Si or Al. Both methods and XRD, as well as FTIR, show greater sensitivity to monitoring the effects of molarity, than the aging time within the same molarity to structural changes in inorganic polymer. SEM micrographs (Fig.1) showed a denser matrix, and a lower content of unreacted metakaolin particles due to increasing of molarity of NaOH. Structural reorganization of inorganic polymer samples occurs during the curing or aging in accordance with a polymerization mechanism

Hybrid Nanoscale Materials for Convergent Technologies

The convergence of nano-, bio-, and information technologies is based on the understanding of complex hierarchical structures and systems, as well as on the material unity at the nanoscale and on technology integration from that scale. A growing interest in these technologies is a result of their potential to provide solutions to numerous societal challenges, such as advanced healthcare, environmental remediation, sustainable development, and adoption of cyber-physical systems based on the Internet of Things and the Internet of Systems. Taking into account that hybrid nanomaterials possess extraordinary physical and chemical properties derived from their size in the nanoscale, the aim of this work is to present the connection between processing parameters and multifunctional properties of nano scale hybrid materials, focusing on the study of ceramic-polymer structures before they can be nano-engineered into functional devices. The unique functionality of these nanostructures has enabled their applications in numerous devices such as: micro and nano-electro-mechanical systems (MEMS/NEMS), sensors, microactuators, surface acoustic wave devices, polymer electrolyte membrane fuel cells, switches, thermistors, resonators and filters, electrooptic devices, etc. In this study special attention has been paid to their applications in the fields of electronics, biotechnology, environmental protection and remediation

Hybrid Nanoscale Materials for Convergent Technologies

The convergence of nano-, bio-, and information technologies is based on the understanding of complex hierarchical structures and systems, as well as on the material unity at the nanoscale and on technology integration from that scale. A growing interest in these technologies is a result of their potential to provide solutions to numerous societal challenges, such as advanced healthcare, environmental remediation, sustainable development, and adoption of cyber-physical systems based on the Internet of Things and the Internet of Systems. Taking into account that hybrid nanomaterials possess extraordinary physical and chemical properties derived from their size in the nanoscale, the aim of this work is to present the connection between processing parameters and multifunctional properties of nano scale hybrid materials, focusing on the study of ceramic-polymer structures before they can be nano-engineered into functional devices. The unique functionality of these nanostructures has enabled their applications in numerous devices such as: micro and nano-electro-mechanical systems (MEMS/NEMS), sensors, microactuators, surface acoustic wave devices, polymer electrolyte membrane fuel cells, switches, thermistors, resonators and filters, electrooptic devices, etc. In this study special attention has been paid to their applications in the fields of electronics, biotechnology, environmental protection and remediation