9 research outputs found
Compressor Speed, Expansion Valve Opening and Refrigerant Charge Influences on the Propane Unit Design
Analiza proizvodnje kukuruza na području Smedereva u periodu 2013-2015. godine
The agro-ecological conditions of the city of Smederevo, maize yields were studied over a three year period (2013-2015.). A total of 13 corn hybrids (8 hybrids of Maize Research Institute Zemun and 5 hybrids Istitute of Field and Vegetable Crops, Novi Sad). Meteorological conditions, especially temperature, distribution and quantity precipitation the growing season had a significant impact on the yield of hybrids during the three years of research.
The most optimal climatic conditions for the growth of corn were in 2014, and on them were all tested hybrids reacted achieve significantly higher yields (average grain yield in 2014 amounted to 11.83 t ha-1) compared to the other two years (6.40 t ha-1 in 2013, and 5.97 t ha-1 in 2015).
Optimal and adequate agricultural techniques, proper selection of hybrids, proper selection of hybrids for a specific localities, and the application of irrigation it is possible to achieve a stable and high yields of maize and to some extent mitigate the impact of unfavorable meteorological factors, primarily drought.U agroekološkim uslovima grada Smedereva ispitivani su prinosi kukuruza u trogodišnjem periodu (2013-2015. godina). Analizirano je ukupno 13 hibrida kukuruza (8 hibrida Instituta za kukuruz Zemun Polje i 5 hibrida Istituta za ratarstvo i povrtarstvo Novi Sad). Meteorološki uslovi, a posebno temperatura, raspored i količina padavina u toku vegetacionog perioda imale su značajan uticaj na prinos ispitivanih hibrida tokom sve tri godine ispitivanja.
Najoptimalniji klimatski uslovi za uspevanje kukuruza bili su u 2014. godini, a na njih su svi ispitivani hibridi reagovali postizanjem znatno većih prinosa (prosečan prinos zrna kukuruza u 2014. godini iznosio je 11,83 t ha-1) u odnosu na ostale dve godine (6,40 t ha-1 u 2013. godini, odnosno 5,97 t ha-1 u 2015. godini).
Optimalnom i adekvatnom agrotehnikom, pravilnim izborom hibrida za odredjeni lokalitet, kao i primenom navodnjavanja moguće je postići stabilne i visoke prinose kukuruza i donekle ublažiti uticaj nepovoljnih meteoroloških faktora, a pre svega suše
Sadržaj pigmenata hloroplasta u lekovitoj biljci Teucrium chamaedrys sa sanirane deponije Rudarsko metalurško hemijskog kombinata “Trepča”
In this paper, the contents of chloroplast pigments (chlorophyll a, b, a+b and carotenoids) in the leaves of medicinal plant Teucrium chamaedrys from tailing pond „Žitkovac“ of Mining and Metallurgical Chemical Company „Trepča“ and from uncontaminated area near city of Niš were compared. Chloroplast pigments were determined spectrophotometrically in the acetone extracts of experimental and control samples of plant material. The contents of chlorophyll a, a+b and ratio a/b were higher in leaves of samples from tailing pond in comparison with control samples from uncontaminated habitat near city of Niš. In response to stress conditions caused by pollution and full intensity of sunlight in samples of leaves from tailing pond providing the protection of chlorophyll from photooxidation or ultraviolet radiation damage.U ovom radu upoređen je sadržaj pigmenata hloroplasta (hlorofil a, b, a+b, karotenoidi) iz listova lekovite bilјne vrste podubica - Teucrium chamaedrys sa deponije „Žitkovac“ Rudarsko Metalurško Hemijskog Kombinata „Trepča“ i nezagađenog područja okoline Niša. Pigmenti hloroplasta su određeni spektrofotometrijski u acetonskim ekstraktima eksperimentalnih i kontrolnih uzoraka bilјaka. Sadržaj hlorofila a, a+b i odnos a/b je bio veći kod u uzorcima listova sa deponije u poređenju sa kontrolnim uzorcima sa nezagađenog staništa iz okoline Niša. Kao odgovor na stresne uslove uzrokovane zagađenjem i punim intenzitetom sunčeve svetlosti zabeležen je i povećan sadržaj karotenoida kod uzoraka listova sa deponije, što obezbeđuje zaštitu hlorofila od fotooksidacije odnosno štetnog dejstva ultravioletnog zračenja
Aktivnost enzima katalaze i sadržaj organskih kiselina kod Hajdučke trave (Achillea millefolium) sa sanirane deponije „Žitkovac“ Rudarsko metalurško hemijskog kombinata „Trepča“
In this comparative study, the activity of enzyme catalase and total content of organic acids were determined in undergroung and above-ground plant parts of medicinal plant Achillea millefolium from tailing pond “Žitkovac” of Mining and Metallurgical Chemical Company „Trepča“ and from uncontaminated area near city of Niš. Catalase activity was measured using the gasometric method and the values obtained for this activity were expressed as ml of O2. The content of organic acids in the plant material was detrmined by modified titration method in the presence of indicator. An increased catalase activity on tailing pond, in comparison with uncontaminated habitat, is a result of stress that is caused by chemical changes in the soil on tailing pond representing good metabolic ways of detoxification, which belongs to the mechanisms of defence and acquiring resistance. An increased content of organic acids in samples on tailing pond is an efficient mechanism reducing the heavy metal uptake, binding them to complexes and allowing the plant growth at high level of contamination.U ovom komparativnom istraživanju određeni su aktivnost enzima katalaze i ukupan sadržaj organskih kiselina u podzemnim i nadzemnim delovima lekovite biljke hajdučka trava (Achillea millefolium) sa sanirane deponije „Žitkovac“ Rudarsko Metalurško Hemijskog Kombinata „Trepča“ i nezagađenog područja okoline Niša. Aktivnost katalaze je izmerena korišćenjem gasometrijske metode i izražena u ml kiseonika. Sadržaj organskih kiselina u bilјnom materijalu određen je modifikovanom metodom titracije u prisustvu indikatora. Uvećanje aktivnosti enzima katalaze kod uzoraka na deponiji u poređenju sa nezagađenim staništem je rezultat stresa uzrokovan hemijskim promenama u zemljištu i predstavlja metabolički vid razgradnje štetnih jedinjenja, odnosno detoksikacije, koja spada u kvalitetne mehanizme sticanja otpornosti, kao odgovor na izmenjene uslove u životnoj sredini. Povećan sadržaj organskih kiselina u uzorcima sa deponije je efikasan mehanizam, koji smanjuje unos teških metala u bilјku vezujući se za njih u komplekse i omogućava rast biljke pri visokom nivou kontaminacije
Analiza stanja i mogućnosti unapređenja proizvodnje strnih žita na teritoriji Gruže i Rudničke Morave
In the area which includes the territory of Gruža and Rudnička Morava agricultural production is the primary work activity of the local population where the grain crops grown on the largest area and production of cereals is present in all the areas of the village. In most of the color producers present the traditional approach in production. This mode of production often affects the achievement of lower average grain yield and low economic returns. Based on a comprehensive analysis of certain conditions it was found that in the short term will be to increase the area under small grains, and the application of modern production technologies increase the average grain yield. Also, in certain regions, where there are favorable conditions could be applied integral and organic vision of production, which would significantly contribute to achieving greater material benefit local populations and foster the accelerated development of the area.Na prostoru koji obuhvata teritorija Gruže i Rudničke Morave poljoprivredna proizvodnja predstavlja osnovnu radnu aktivnost lokalnog stanovništva pri čemu se strna žita gaje na najvećoj površini a proizvodnja žitarica je prisutna u atarima svih sela. Kod najvećeg boja proizvođača prisutan je tradicionalni pristup u proizvodnji. Ovaj način proizvodnje često utiče na postizanje prosečno nižih prinosa zrna i niske ekonomske dobiti. Na osnovu sveobuhvatne analize pojedinih uslova utvrđeno je da bi u kratkoročnom periodu mogle da se povećaju površine pod strnim žitima i da se primenom savremene tehnologije proizvodnje povećaju prosečni prinosi zrna. Takođe, u pojedinim regijama, gde postoje povoljni uslovi mogao bi da se primeni integralni i organski vid proizvodnje, čime bi se značajno doprinelo ostvarivanju veće materijalne dobiti lokalnog stanovništva i pospešio ubrzani razvoj područja
Analytical Entropy Analysis of Recuperative Heat Exchangers
Abstract: The analytical solutions for the temperature variation of two streams in parallel flow, counter flow and cross-flow heat exchangers and related entropy generation due to heat exchange between the streams are presented. The analysis of limiting cases for the relative entropy generation is performed, and corresponding analytical expressions are given. The obtained results may be included in a more general procedure concerning optimal heat exchanger design
Is There a Relationship Between Audiogram Shape and the Intensity and Duration of Tinnitus?
Chronic tinnitus is often associated with hearing impairment, but it cannot be asserted that only hearing loss causes tinnitus. Audiograms of patients with tinnitus show that hearing loss occurred more often at high frequencies than at low frequencies
Stereospecific ligands and their complexes. Part VII. Synthesis, characterization and in vitro antitumoral activity of platinum(II) complexes with O,O '-dialkyl esters of (S,S)-ethylenediamine-N,N '-di-2-(4-methyl)pentanoic acid
Platinum(II) complexes (1-4) with bidentate N,N'-ligands, O,O'-dialkyl esters (alkyl = ethyl, n-propyl, n-butyl and n-pentyl), of (S,S)-ethylenediamine-N,N'-di-2-(4-methyl)pentanoic acid were synthesized and characterized by IR, (1)H NMR and (13)C NMR spectroscopy and elemental analysis. DFT calculations were performed for the complexes and it was found that only one diastereoisomer could be formed. Cytotoxic activity of complexes 1-4 was determined against chronic lymphocytic leukemia cells (CLL) and compared to the activity of ligand precursors L1 center dot 2HCl-L4 center dot 2HCl and corresponding palladium(II) complexes, [PdCl(2)L] (L = L1-L4). The complexes were found to exhibit significantly higher antitumor activities than cisplatin on CLL cells. Cytotoxic effect of platinum(II) complexes on CLL cells was higher compared to corresponding palladium(II) complexes. In addition the mode of cell death induced by platinum(II) complexes was determined