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Morfološka analiza populacija vrsta roda Plantago
Get PDFDetailed exploration of morphological variability and ecological differentiation of a species, is a prerequisite for a comprehensive understanding of biological potential and evolutionary state in which the analyzed plant is found. Due to the wide distribution and high importance of the species of genus Plantago, in this paper we analyzed their morphological variability. The aim of this work was testing the coefficient of variation of a specific number of properties, and determining the most variable and the most consistent character. The plant material was collected in the period August-September. We sampled 30 individuals from each site, for two species of the genus Plantago (Plantago lanceolata L. and Plantago major L.). Three different characters were tested: the length of inflorescence, the flower stem length and the width of leaf. The obtained results were statistically analyzed, and they indicate a pronounced variability of all examined characters.Detaljno upoznavanje morfološke varijabilnosti i ekološke diferencijacije vrste predstavlja neophodan uslov za cjelovito sagledavanje biološkog potencijala i evolucionog stanja u kome se analizirana biljka nalazi. Zbog široke rasprostranjenosti i velikog značaja vrsta roda Plantago, u ovom radu izvršena je analiza njihove morfološke varijabilnosti. Cilj rada je bio ispitivanje koeficijenta varijabilnosti određenog broja osobina i utvrđivanje najvarijabilnijeg i najkonzistentnijeg karaktera. Biljni materijal je prikupljen u periodu avgust-septembar. Uzorkovano je po 30 jedinki sa svakog lokaliteta za dvije vrste roda Plantago: (Plantago lanceolata L. i Plantago major L.). Ispitana su tri karaktera: dužina cvasti, dužina cvjetne drške i širina lista. Dobijeni rezultati su statistički obrađeni i ukazuju na izraženu varijabilnost svih ispitivanih karaktera
Uticaj veličine čestica polianilina na imobilizaciju alfa-amilaze
Get PDFIn this paper polyaniline was synthesized by interfacial polymerization of monomer aniline in a water/chloroform system. Four fractions of polyaniline microparticles (in the range of 90-800 μm) are used as a support for immobilizing the alpha-amylase from Bacillus licheniformis. The equilibrium amount of enzyme, amount of washed enzyme, adsorption yield , the activity of immobilized enzyme and activity yield were studied. It was found that the maximum amount of the adsorbed enzyme was to a particle size of 90-160 μm, but at the same time from these particles enzymes were desorbed to larger extent during washing. However, it has been shown that as the particle size increased the activity of the immobilized enzyme decreased with the exception of the particle sizes of 160-315 μm and the activity of immobilized enzyme was not dependent on adsorption yield. The highest average activity yield of adsorbed α-amylase, 4,62% was at polyanilne particle size of 160-315 μm .U ovom radu sintetisane su čestice polianilina postupkom polimerizacije anilina na granici dve faze voda/hloroform. Četiri frakcije dobijenih mikročestica polianilina u opsegu od 90-800 μm korišćene su kao nosač za imobilizaciju enzima alfa-amilaze iz Bacillus licheniformis. Određena je ravnotežna masa enzima, masa ispranog enzima, prinos mase, aktivnost dobijenog biokatalizatorskog sistema kao i prinos aktivnosti. Utvrđeno je da se najveća masa enzima veže za čestice veličine 90-160 µm, ali da se sa ovih čestica i najviše enzima desorbuje tokom ispiranja. Međutim, pokazano je da se sa povećanjem veličine čestica smanjuje aktivnost imobilisanog enzima sa izuzetkom čestica dimenzija od 160-315 μm, pri čemu aktivnost imobilizata ne zavisi od prinosa mase. Prinos aktivnosti imobilisane α-amilaze u odnosu na aktivnost slobodnog enzima koji se vezao za nosač prosečno je najveći kod čestica veličine 160-315 μm
Mikrobiološki kvalitet proizvoda pekare "Pons" D.O.O. Čačak
Get PDFThe aim of this study was to evaluate the microbiological quality of various bakery products, determine the critical points and causes of their contamination and make recommendations for the implementation of protective measures. In the Sector for the production of cakes and sandwiches were the largest deviation from the permissible values in relation to coagulase-positive staphylococci, E. coli, the total number of microorganisms and Enterobacteriaceae, whereas in the Sector for the production of frozen pastry deviation was compared to E. coli, and in the Sector for the production of the pies and burek relative to the E. coli and fungi. In all three production sectors most vulnerable to microbiological contamination were the most sensitive products, such as cream puff, Danish salty and burek with cheese, meat and cabbage. As prevention of microbial contamination of these products is proposed storage of raw materials in a clean, dry and ventilated areas, maintaining a constant temperature and relative humidity in the premises for the storage of finished products, maintaining a high level of personal hygiene of workers, rapid cooling of finished products, timely undertaking of sanitation measures and automation of production process.Cilj ovog rada je bio da se ispita mikrobiološki kvalitet različitih pekarskih proizvoda, utvrde kritične tačke i uzroci njihove kontaminacije i daju preporuke za sprovođenje mera zaštite. U Sektoru za proizvodnju kolača i sendviča bilo je najveće odstupanje od dozvoljenih vrednosti u odnosu na koagulaza-pozitivne stafilokoke, E. coli, ukupan broj mikroorganizama i Enterobacteriaceae, dok je u Sektoru za proizvodnju zamrznutog peciva odstupanje bilo u odnosu na E. coli, a u Sektoru za proizvodnju pita i bureka u odnosu na E. coli i plesni. U sva tri ispitivana proizvodna sektora mikrobiološkoj kontaminaciji najpodložniji su bili najosetljiviji proizvodi, kao što su princes-krofne, dansko slano i bureci od sira, mesa i zelja. Radi preventive mikrobiološke kontaminacije ovih proizvoda predlaže se skladištenje sirovina u čistim, suvim i provetrenim prostorijama, održavanje stalne temperature i relativne vlažnosti u prostorijama za skladištenje gotovih proizvoda, održavanje visokog nivoa lične higijene radnika, brzo hlađenje gotovih proizvoda, blagovremeno preduzimanje mera sanitacije i automatizacija proizvodnih procesa
Uticaj aplikacije Niacina u peripartalnom periodu krava na proizvodnju mleka do postizanja pika laktacije
Get PDFThe aim of this study is to determine whether the use of niacin in the peripartum affects milk production in cows in the initial niacin early laktaciji.15 cows and 15 cows were presented a negative control. Niacin is managed through food orally. We used a preparation in a dose that allows access to the intestine, about 6-12g niacin / day. The application of niacin tendency towards positive action on the production of milk for 30 days of lactation (p <0.1), but this trend is lost if we look at a longer period from birth to 60.dana lactation. Although there were no statistically significant differences in milk production, from a practical point of view, it is important to determine the percentage of cows in the group who received niacin that had statistically significant higher milk production than in a group that did not get niacin. The analysis of frequency allocation, beta fixes and statistical power of the test is calculated that 60% of the cows showed significantly higher production of milk cows in the group who received niacin compared to control, but with the progress of lactation, this percentage decreases, and 60 days of lactation have only 26 , 6% of cows that are significantly higher milk production compared to the control. The use of niacin can improve milk production in cows in early lactation.Cilj ovog rada je da se utvrdi da li aplikacija niacina u peripartalnom periodu utiče na proizvodnju mleka kod krava u ranoj laktaciji.15 krava je primal niacin, a 15 krava su predstavljane negativnu kontrolu. Niacin je aplikovan putem hrane per os. Korišćen je preparat u dozi koja omogućuje dostupnost u crevima oko 6-12g niacina/dan. Aplikacija niacina pokazuje tendenciju pozitivnog delovanja na proizvodnju mleka do 30. dana laktacije (p<0,1), ali se ova tendencija gubi ako posmatramo širi period od partusa do 60.dana laktacije. Iako nije bilo statistički značajne razlike u proizvodnji mleka, sa praktičnog aspekta je značajno odrediti koji je to procenat krava u grupi koja je primala niacin koji je imao statistički značajno veću proizvodnju mleka u odnosu na grupu krava koja nije primala niacin. Analizom distribucija frekvencije, beta greške i statističke snage testa izračunato je da je 60% krava pokazalo statistički značajno veću proizvodnju mleka u grupi krava koja je primala niacin u odnosu na kontrolu, ali se sa napredovanjem laktacije taj procenat smanjuje, pa 60. dana laktacije imamo samo 26,6% krava koje su pokazale značajno veću proizvodnju mleka u odnosu na kontrolu. Upotreba niacina može poboljšati proizvodnju mleka kod krava u ranoj laktaciji
Razvoj monitoring sistema u poljoprivredi
Get PDFKnowledge about relationship between plants and the environment, in which they vegetate, is one of the prerequisites for optimizing plant production. Therefore, monitoring systems play an important role in agriculture. These systems allow you to collect data about conditions in the field via sensor networks, which nowadays increasingly function in the concept of "Internet of Things". The data collected with sensor devices are processed on the server side through the "Complex Event Processing System". Those systems are characterized by the ability to define rules that are applied over the data at the same time as they are collected. On the basis of these rules detection of certain values, that are important to the user, would be achieved. By applying this system users in the shortest possible time would be informed about detected values and can take appropriate actions.Poznavanje odnosa između biljnih vrsta i životne sredine u kojoj se nalaze staništa gajenih biljaka jedan je od preduslova za optimizaciju biljne proizvodnje. U okviru proizvodnog polja sistemi za praćenje useva (monitoring sistemi) imaju značajnu ulogu u poljoprivredi. Ovi sistemi omogućavaju prikupljanje podataka o uslovima na proizvodnom polju preko senzorskih mreža koje danas sve više funkcionišu u okviru koncepta „Internet of Things“. Prikupljeni podaci sa senzorsih uređaja procesiraju se na serverskoj strani preko „Complex Event Processing sistema“. Navedene sisteme karakteriše mogućnost definisanja pravila koja se primenjuju istovremeno sa prikupljanjem podataka. Zadata ili unapred definisana pravila obezbeđuju detekciju kritičnih zadatih vrednosti od strane krajnjeg korisnika. Primenom ovakvog sistema krajnji korisnici to jest proizvođači u najkraćem realnom vremenu dobijaju obaveštenja o detektovanim vrednostima i mogu preduzeti odgovarajuće korektivne mere
Prinos i evapotranspiracija ozime pšenice u rejonu Niša
Get PDFThe aim of this study was to determine the evapotranspiration of wheat, and the methods for calculating potential evapotranspiration and water needs of wheat for the area of Nis. On the experimental field produced wheat yield of 4.25 t ha-1. The total measured water consumption evapotranspiration was 319 mm. Calculated the coefficient of utilization of water (WUE) of wheat of 13.3 kg ha-1 mm-1. Linear regression analysis between measured ET and calculated ETPo determined highly significant correlations.Cilj rada je bio da se utvrdi evapotranspiracija pšenice, a metodama za obračun potencijalne evapotranspiracije i potrebe za vodom pšenice za rejon Niša. Na oglednom polju dobijen je prinos zrna pšenice od 4,25 t ha-1. Ukupan izmeren utrošak vode na evapotranspiraciju bio je 319 mm. Obračunat je koeficijent iskorišćenosti vode (WUE) pšenice od 13,3 kg ha-1 mm-1. Analizom linearne regresije između izmerene ET i obračunate ETPo utvrđena je visoko signifikantna korelacija
Efekat teških metala (Cd, Fe, Ni, Zn) na klijanje semena robinia pseudoacacia l.
Get PDFIn our study we researched the inhibitory effect of different concentrations of heavy metals (Cd, Fe, Ni, Zn) on germination and growth on Robinia pseudoacacia L. radicle. The results showed that the percentage of seed germination and growth of radicle is inversely correlated with the concentration of the investigated metals. The strongest inhibitory effect has cadmium and the weakest effect has nickle. Robinia pseudoakacia L. is tolerant, to some degree on the concentration of heavy metals of 1 mol /m3, 0.1 mol /m3 and 0.01 mol /m3.Matični supstrat je prirodni izvor teških metala u zemljištu. Ubrzanim tehnološkim razvojem antropogeni izvori teških metala su postali značajni zagađivači zemljišta. Robinia pseudoacacia L., invazivna vrsta flore Srbije, tolerantna je vrsta prema brojnim ekološkim faktorima što joj omogućava da sve više širi svoj areal. Prvi uslov prirodnog širenja populacija bagrema na različitim zemljištima je mogućnost klijanja semena. U radu smo ispitali sposobnost klijanja semena i rast korenka R. pseudoacacia L. u uslovima stresa izazvanim različitim koncentracijama teških metala Cd, Ni, Fe, Zn. Rezultati su pokazali da semena imaju izvesnu stopu tolerantnosti na ispitivane metale u koncentracijama 1mol/m3, 0,1mol/m3 i 0,01mol/m3 svih ispitivanih metala
Karakteristike vuče, obrtnog momenta i klizanja kočenog točka sejalica i sadilica
No full textSowing or planting is one of the most important farm operations.
Generally it is done by seed drill and planters. Metering device govern the seed to seed
spacing in sowing operation. A constant velocity ration between the ground wheel shaft
and the shaft of metering device helps in maintaining regular hill to hill spacing.
Metering device requires torque for its operation which is derived from the ground
wheel. Therefore, the ground wheel in seed drills and planters works as a braked wheel.
The braked wheel experiences negative slip which is known as skid. Excessive value of
skid will result in alteration of spacing between hills. Skid increases with the increase in
braking torque resulting in large variations in hill to hill spacing. Hence, the relationship
between braking torque and skid is important to the designer of seed drills and planters.
The relationships between pull, torque and slip characterizes the behavior of the braked
wheel. An experiment was carried out to determine skid at different lug height (15, 20,
25, 30, 35 and 40 mm), different axle load (98.1, 147.15 and 196.2 N) and different
torque. A regression model was developed relating skid (s) with lug height (L) and
torque (T). Axle load had no significant effect on skid in the range studied. The
regression model was a quadratic polynomial equation having (R2 = 0.82). Expected
value of skid at different values of lug height and braking torque were calculated from
the regression equation and given in a table. This can be used for determining lug height
when torque requirement and permissible level of skid were known. It can be seen that
skid increases with decrease in lug height almost for all values of braking torque.Setva ili sadnja su među najvažnijim operacijama u poljoprivredi. Merni
uređaj na sejalici ili sadilici određuje rastojanje između zrna. Konstantan odnos brzine
vratila pogonskog točka i vratila mernog uređaja održava pravilno rastojanje između
sadnica. Merni uređaj zahteva pogonski obrtni moment od pogonskog točka. Zato
pogonski točak pri trenju sa podlogom radi kao kočeni točak. On trpi negativno klizanje
poznato kao klizno kočenje. Porast vrednosti prokljizavanja dovodi do promene
rastojanja između sadnica. Povećano klizanje sa povećanjem momenta kočenja dovodi
do značajnih variranja u rastojanju između sadnica. Zato je za konstruktore sejalica i
sadilica važan odnos kočionog momenta i klizanja. Odnosi između vuče, momenta i
klizanja karakterišu ponašanje kočenog točka. Ovaj ogled je izveden da bi se odredilo
klizanje pri različitim visinama poteznice (15, 20, 25, 30, 35 i 40 mm), različitim
osovinskim opterećenjima (98.1, 147.15 i 196.2 N) i različitim obrtnim momentima.
Razvijen je regresioni model koji uključuje klizanje (s), visinu poteznice (L) i obrtni
moment (T). Osovinsko opterećenje nije imalo značajan uticaj na klizanje u ispitivanom
opsegu. Regresioni model je imao oblik kvadratne polinominalne jednačine (R2 = 0.82).
Očekivana vrednost klizanja pri različitim visinama poteznice i kočionim momentima
izračunavani su iz regresione jednačine i prikazani u tabeli. Ovo se može upotrebiti za
određivanje visine poteznice kada su poznati potrebni obrtni moment i dozvoljeni nivo
klizanja. Može se uočiti da klizanje raste sa opadanjem visine poteznice pri skoro svim
vrednostima kočionog momenta
Mineral Profile of Some Dried Fruits
Get PDFThe aim of this work was to determine the content of 16 elements in the seven samples of dried fruits: plums (Prunus domestica), figs (Ficus carica), apricots (Prunus armeniaca), white and black raisins (Vitis vinifera), dates (Phoenix dactylifera) and cranberries (Vaccinium oxycoccus), which are available in local markets. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used after wet digestion method. Potassium is the most common macroelement while boron and zinc are the most common microelements. As, Cd and Hg were not detected while the content of Pb is below the MAC. The obtained results were statistically analyzed and compared with the literature values
Uticaj biohemijskog sastava ploda na senzoričku ocenu kvaliteta ploda novointrodukovanih sorti jagode
Get PDFThe paper presents the results of the study conducted into the impact made by biochemical composition on sensory appraisal of the fruits of the ʻClery’, ʻJoly’ and ʻDely’ strawberry cultivars in the period 2012–2013. In 2012 a significantly higher content of total sugars was recorded in ʻDely’ and ʻClery’ cultivars, compared to ʻJoly’ cultivar. In 2013, a significantly higher content of total and reduced sugars were determined in the ʻJoly’ and ʻDely’ cultivar compared to ‘Clery’. Within the scope of the two years of research, the highest contents of sucrose was recorded in the ‘Joly’ strawberry cultivar. In the first trial year, the highest content of total acids was recorded in the ‘Clery’ cultivar, whereas in the second trial year the highest total acids content was found in the ‘Joly’ cultivar. A high cumulative grade for the sensory quality of fruit was attained by the ‘Joly’ cultivar, whereas the lowest cumulative grade was given to the ʻClery’ cultivar in both trial years. Considering the best score for the biochemical composition and sensory quality of the fruit, the ‘Joly’ cultivar can be recommended for more intensive use in the production practice.U radu su prikazani rezultati proučavanja uticaja biohemijskog sastava ploda na senzoričku ocenu kvaliteta ploda jagode sorti ʻClery’, ʻJoly’ i ʻDely’ u periodu 2012–2013. godina. Značajno viši sadržaj ukupnih šećera registrovan je kod sorti ʻDely’ i ʻClery’ u poređenju sa sortom ʻJoly’, u 2012. godini. U 2013. godini, značajno viši sadržaj ukupnih i invertnih šećera evidentiran je kod sorti ʻJoly’ i ʻDely’ u odnosu na sortu ‘Clery’. U dvogodišnjem periodu istraživanja, najveća vrednost sadržaja saharoze evidentirana je u plodu jagode sorte ʻJoly’. U prvoj godini istraživanja, najviši sadržaj ukupnih kiselina zabeležen je kod sorte ʻClery’, a u drugoj godini istraživanja kod sorte ʻJoly’. Visoke zbirne ocene za senzorički kvalitet ploda ostvarila je sorta ʻJoly’, a najniže zbirne ocene sorta ʻClery’, u obe godine istraživanja. Najbolje rezultate u pogledu biohemijskog sastava i senzoričkog kvaliteta ploda ostvarila je sorta ʻJoly’, pa se ova sorta može preporučiti za intenzivnije širenje u proizvodnoj praksi