61 research outputs found
Potrošnja energije u objektima zaštićenog prostora različite konstrukcije
In this paper different greenhouse structures were analyzed regarding energy
consumption and energy productivity in winter lettuce production. Greenhouse
production is still among most energy consuming branches in agriculture with very high
investments and annually costs. This is the reason why plastic covering are introduced as
mean of making this kind of plant production more efficient. Also, as a mean of
lowering energy consumption, tunnel structures are proposed. Three different double
plastic covered greenhouses were used for energy analysis. Two tunnel types, 9x 58m
and 8 x 25m covered with double 180μm PE UV IR folia, and one gutter connected
plastic covered greenhouse 7 x 39m. Inner folia was 50μm and outside folia was 180μm.
Results show lowest energy consumption for gutter connected greenhouse. Energy out/in
ration was also higher in gutter connected greenhouse. Highest energy consumptions was
obtained in tunnel 8 x 25m.Obzirom da je proizvodnja u zaštićenom prostoru grana poljoprivrede sa
najvećom potrošnjom energije i najvišim godišnjim troškovima, proizvođačima se na
tržištu nude različiti oblici konstrukcije, pre svega konstrukcije tunel tipa u varijantama
sa jednostrukom i dvostrukom folijom, kao ekonomski i energetski najefikasniji. U radu
su analizirani, sa aspekta potrošnje energije, najčešće korišćeni oblici konstrukcije
objekata zaštićenog prostora na teritoriji Srbije. Dva objekta tunel tipa, 9 x 58 m i 8 x 25
m pokriveni dvostrukom 180μm PE UV IR folijom, i blok objekat sa dva broda 14 x 39
m pokriven dvostrukom folijom (unutrašnja 50μm, spoljašnja 180μm). Rezultati
pokazuju da je najniža specifična potrošnja energije ostvarena u blok objektu. Stepen
iskorišćenja energije je takođe bio viši kod blok objekta. Najviša specifična potrošnja
energije ostvarena je u objektu tunel tipa 8 x 25 m
Energetska efikasnost proizvodnje paradajza na otvorenom i u objektima zaštićenog prostora različite konstrukcije
The aim of this paper is to analyze energy patterns in open and greenhouse
tomato production, since tomato is very important vegetable in human nutrition with
tendency to be used whole year. The greenhouses used were one tunnel structure,
covered with double PE folia, 5 x 20 m and one gutter-connected double PE covered
structure 21m wide and 250m long. The results obtained lead to the conclusion that
lower specific energy per production surface can be expected in conditions of the open
filed and that, regarding the greenhouses lower value for energy consumption can be
expected in case of multi-span greenhouses.Obzirom na intenzivnost korišćenja paradajza u ljutskoj ishrani, za proizvođače
je od izuzetnog značaja energetska, ekonomska i ekološka efikasnost proizvodnje.
Obzirom da se paradajz gaji kako na otvorenom tako i u objektima zaštićenog prostora
cilj istraživanja je bio analiza proizvodnje na otvorenom polju i u objektima zaštićenog
prostora tunel i blok tipa sa aspekta potrošnje energije i energetske efikasnosti. Objekat
tunel tipa dimenzija je 5 x 20 m i pokriven je dvostrukom 180μm PE UV IR folijom.
Blok objekat je sa dva broda, dimenzija 21 x 250 m pokriven dvostrukom PE UV IR
folijom. Rezultati ukazuju da se niža potrošnja energije po jedinici površine može
očekivati na otvorenom, a da se, kada su objekti zaštićenog prostora u pitanju niža
potrošnja energije može očekivati kod objekata veće specifične zapremine tj. objekata
blok tipa
Metode integralne zaštite bilja u objektima zaštićenog prostora
Highly intensive greenhouse production can't be imagined without peramnent
control and surveliance of production conditions and plant health. Concerning
regulations limitating the presence of pesticide and minimizing the impact of overall
program on the environment, most producers are accepting integrated pest management
(IPM) as a concept of plant protection. Main parts of this concept are prevention,
surveillance and control. Covering materials and insect screens, UV lamps and sticky
traps are proposed as a method for insect exclusion from greenhouses.
The aim of this paper is to show the possibilities and effects of using UV absorbing
materials. Criteria for insect screen selection are also presented together with
possibilities of UV lamp usage in eliminating insects from greenhouses. The influence of
applying IPM concept on energy consumption and chemicals savings in production
processes is given.Visoko intenzivna biljna proizvodnja u zaštićenom prostoru podrazumeva
stalnu kontrolu i praćenje proizvodnih uslova i zdravstvenog stanja useva. Obzirom na
sve strožije regulative o primeni hemijskih zaštitnih sredstava, zatim na otpornost
insekata na određene pesticide, na sve strožije kriterijume potrošača u smislu
zdravstveno bezbedne hrane, poljoprivredni proizvođači se, sve češće, opredeljuju za
koncept integralne zaštite bilja. U osnovi ovog koncepta, u objektima zaštićenog
prostora, su prevencija, praćenje i kontrola. Kao mogući načini prevencije primenljivi su
pokrivni materijali i mreže protiv insekata, i, kao metode mehaničkog odstranjenja
insekata iz objekata, lepljive trake različitih boja i UV lampe.
Cilj ovog rada je da prikaže mogućnosti i efekte korišćenja UV apsorbujućih
pokrivnih materijala, zatim da analizira kriterijume izbora mreža protiv insekata i
mogućnost primene specijalnih UV apsorbujućih lampi u smanjenju broja insekata u
objektu a samim tim i uticaj navedenih tehnologija na potrošnju hemijskih zaštitnih
sredstava i energetski bilnas biljne proizvodnje u zaštićenom prostoru
Kinetic Study of Oxidation Degradation of Polyphenols in Sour Cherry and Blackberry Extracts During Storage
In this study was to investigate the influence of storage time, light and temperature on stability of polyphenols in sour cherry (Prunus cerasus) and blackberry (Rubus fruticosus), were harvested in western Serbia (Rasinski region). Total phenol content was monitored in the fruit extracts during 23 days stored at 7°C under darkness and 90 days storage at 23°C in oxygen. For analyzed extracts, first-order reaction kinetics was established for the degradation process of polyphenols. The temperature dependence of the polyphenols degradation rate constants was expressed by the temperature coefficients Q10 of the process. It is found that the Q10 values of polyphenols degradation in sour cherry and blackberry extracts were 1.247 and 3.239, respectively
Energetski bilans proizvodnje rasada paradajza i krastavca u zaštićenom prostoru
Greenhouse production is most energy consuming branch in agriculture and in
same time with lowest energy efficiency. Concerning the fact that energy input in
greenhouse production has a highest share in product market price, more detailed energy
analysis must be taken.
In this paper energy analysis of tomato and cucumber seedlings production is given.
Tomato and cucumber seedling were produced in double plastic covered tunnel. Energy
consumption and energy productivity per seedling were calculated.Proizvodnja povrća u zaštićenom prostoru predstavlja granu poljoprivrede sa
najvećom potrošnjom energije i niskom energetskom efikasnošću. Utrošena energija u
proizvodnji povrća čini najveći deo u strukturi cene koštanja gotovog proizvoda. Otuda i
potreba da se detaljnije ispitaju svi energetski inputi, kako bi se povećala energetska
efikasnost proizvodnje i samim tim smanjila cena gotovog proizvoda.
U ovom radu su definisani energetski inputi (direktni i indirektni) u proizvodnji
rasada paradajza i krastavca i prikazana je potrošnja energije za datu biljnu proizvodnju
Klimatski uslovi u objektima zaštićenog prostora i mogućnosti njihove kontrole
Successful greenhouse production is defined by four main factors –
temperature, light, water content of the air and soil, and quality of air inside the objects.
The greates influence of all these factors and highest variations during production
processes has temperature. Plants demands are various and they dictate the time of
seeding or planting and the type of construction that is most suitable for the production.
Temperatures inside the objects define plant growth intensitz, fruit quality and time
picking. These are the reasons why good control of temperature is needed.
In this paper climatic conditions in greenhouses are analysed and possibilities of
their good control are given. Vertical and horizontal temperature distribution are shown
for double plastic covered tunel during tomato production. Established values, that show
temperature and air relative humidity variation in greenhouse, can be used for heating
system design and installation. Influnce of air quality on time of picking and production
quality is also shown.Faktori uspešnosti biljne proizvodnje u zaštićenom prostoru su temperatura,
svetlost, vlažnost vazduha i zemljišta i sastav i kvalitet vazduha. Najveći uticaj na biljke,
a istovremeno i najveće variranje tokom ciklusa proizvodnje, ima temperatura. Zahtevi
pojedinih biljaka za toplotom uslovljavaju vreme njihove setve/sadnje i tip objekta u
kome je moguće njihovo gajenje. Svakako da biljke sa manjim potrebama za toplotom
mogu da uspevaju u svim tipovima zaštićenog prostora, dok toploljubive zahtevaju
gajenje u objektima sa dopunskim zagrevanjem. Temperatura u proizvodnom prostoru
biljke određuje intenzitet porasta, kvalitet plodova, vreme ubiranja, te su njeno
određivanje i kontrola od izuzetnog značaja. U zavisnosti od tipa zaštićenog prostora,
temperatura može značajno varirati u različitim delovima objekta.
U radu je data analiza klimatskih uslova u objektima zaštićenog prostora i
mogućnost njihovog praćenja i kontrole. Analiziran je raspored temperatura u objektima
i to po dužini, širini i visini objekta. Temperature su praćene u objektu “tunel tipa”
tokom proizvodnje paradajza. Utvrđene vrednosti, koje pokazuju određena variranja
temperature, mogu poslužiti za kasnije projektovanje tehničkih sistema zagrevanja i
njegovog postavljanja. U radu je prikazan i uticaj sastava i kvaliteta vazduha na vreme
ubiranja i kvalitet plodova. Analizirani su i ostali mikroklimaski uslovi i njihov uticaj na
rast i razviće biljaka
Struktura zemljišta nakon dopunske obrade
Tillage exposes the soil to different mechanisms of mechanical decomposition,
which crucially change its structure. Possible approach in controlling the quality of each
specified operation and complete tillage process assumes establishing the functional
relations between the operational parameters of applied mechanization and resulting
mass probability density function of soil particle sizes. Based on experimental data from
three independent experiments, the appropriate nonlinear relationships between the mass
probability density functions of different soil fractions and particle diameters of these
fractions. Calculations are based on the least squares fitting method. These expressions
can facilitate modeling and prediction of soil fractions distribution and tillage quality
control.Mehanizovana obrada izlaže zemljište uticaju različitih mehanizama mehaničke
dekompozicije, suštinski menjajući njegovu strukturu. Mogući pristup analizi kvaliteta
svake pojedinačne operacije i procesa obrade u celini podrazumeva uspostavljanje
funkcionalnih veza između radnih parametara primenjene mehanizacije i rezultujuće
masene raspodele frakcija obrađenog zemljišta. Na osnovu eksperimentalnih podataka iz
tri nezavisna eksperimenata, formulisane su odgovarajuće nelinearne veze funkcije
masene gustine verovatnoće različitih frakcija obrađene oranice i pripadajućih prečnika
čestica tih frakcija. Proračun je zasnovan na metodi najmanjih kvadrata. Dobijeni izrazi
mogu olakšati modeliranje i procenu veličina frakcija zemljišta, kao i kontrolu kvaliteta
mehanizovane obrade oranice
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