Return to Izdanja 2019. godine

Zaštita materijala 4. 2019

 

Hivzo Skrijelj1, Dalibor Radovanovic2, Dusan Markovic3, Srdjan Jovic1*

1University of Pristina, Faculty of Technical Sciences in Kosovska Mitrovica, Kosovska Mitrovica, Serbia, 2Sinergija University Bijeljina, Bijeljina, Republic of Srpska, Bosnia and Hertzegovina, 3University of Singidunum, Belgrade, Serbia

Scientific paper

ISSN 0351-9465, E-ISSN 2466-2585
UDC:502.171:531.62 -048.34+633.11
doi: 10.5937/zasmat1904321S

Zastita Materijala 60 (4)
321 – 330  (2019)

Application of evolutionary algorithm in estimation of environmental performance in farm systems

Abstract

The vast application of energy from different resources in agricultural production has resulted in negative environmental consequences. The importance of food security and sustainable production is undeniable therefore finding appropriate solutions to meet world’s food requirements from one hand and environmental requirements from the other hand has become an interesting topic in the recent decades. Evolutionary algorithm (EA) can be employed in these problems because they can simultaneously focus on two or more objective functions. Multi-objective genetic algorithm (MOGA) as one of the EAs was selected and wheat as one of the most important strategic crops was chosen in order to test the application of these algorithms in farm systems. MOGA was employed to find the best mix of agricultural inputs which can be able to minimize greenhouse gas emissions and maximize output energy and benefit cost ratio simultaneously.  The results revealed that on average 41% of the total energy input can be reduced and simultaneously, 68% of the total greenhouse gas emissions (GHG) emissions can be decreased. The outcomes demonstrated that on average a total amount of 28024 MJ energy from different sources is needed for wheat cultivation in the region while in the present condition on average an amount of 47225 MJ per ha is consumed. This amount of energy is responsible for 4217 kg CO2 while it can be reduced to the value of 1502 kg CO2 per ha wheat cultivation. The outcomes of the present study showed the valuable application of multi-objective genetic algorithm for optimization of energy consumption in wheat cultivation.

Keywords: Optimization; Energy management; Wheat; Greenhouse gas emissions.

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APLIKACIJA EVOLUCIONOG ALGORITMA ZA ESTIMACIJU UTICAJA SISTEMA FARME NA PRIRODU

Izvod

Široka primena energije od različitih izvora u poljoprivrednoj proizvodnji je rezultovalo u negativnom uticaju na prirodu. Važnost sigurnosti hrane i održiva proizvodnja je neizbežna i prema tome pronalazak pogodnih solucija za zadovoljavanje svetskih zahteva za hranu kao i zahteva spoljašne prirodne okoline je interesantan zadatak u skorijim dekadama. Evolucioni algoritmi se mogu koristiti za ove probleme zato što oni mogu simultano da se fokusiraju na više ciljnih funkcija. Višekriterijumski genetski algoritam je jedan od tih evolucionih algoritama koji je korišćen u ovom radu, a pšenica je korišćena kao jedan od najbitnijih izvora hrane. Cilj je bio pronaći optimalne ulazne parametre koji će minimizovati emisiju gasova staklene bašte i maksimizovati izlaznu energiju istovremeno. Rezultati prikazuju da u proseku 41% ukupne ulazne energije se može smanjiti i simultano, 68% od ukupne emisije staklene bašte se može smanjiti. Retultati prikazuju da je ukulno 28024 MJ ukupne energije potrebno od različitih izvora za obrađivanje pšenice u datom regionu dok je u datim uslovima ukupno 47225 MJ potrešene energije u proseku. Ta količina energije je odgovorna za 4217 kg CO2 dok se to može smanjiti na vrednosti od 1502 kg CO2 po hektaru za proizvodnju pšenice. Dobijeni rezultati u ovom istraživanju prikazuju korisnu aplikaciju više kriterijumskih genetskih algoritama za optimizaciju potrošnje energije u proizvodnji pšenice.

Ključne reči: Optimizacija; Menadžment energije; Pšenica; Emisija staklene bašte.

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Jelena Radivojević1, Evica Ivanović1, Jelena Popović-Djordjević1, Nemanja Trišović2, Nebojša Banjac1*

1Univerzitet u Beogradu, Poljoprivredni fakultet, Katedra za hemiju i biohemiju, Beograd, Srbija, 2Univerzitet u Beogradu,Tehnološko-metalurški fakultet, Beograd, Srbija

Naučni rad
ISSN 0351-9465, E-ISSN 2466-2585
UDC: 547.556.33:544.164.032.732
doi: 10.5937/zasmat1904331R

Zastita Materijala 60 (4)
331 – 335  (2019)

Solvent influence on absorption spectra of food azo dyes

Abstract

The solvent influence on absorption spectra of food azo dyes was examined by the method of Linear Solvation Energy Relationships (LSER). For this purpose, six azo dyes were used: tartrazine (E 102), ponceau 4R (E 124), azorubin (E 122), brilliant black (E 151), amaranth (E 123) and gelb orange S (E 110). Absorption spectra of dissolved azo dye have been recorded in the wavelength range of visible radiation, or from 380 to 760 nm, in eight solvent of different polarity. The choice of the solvent was limited due to the high polarity of the azo dye molecules themselves. The effect of solvent dipolarity/polarizability and solvent/solute  hydrogen bonding interaction are analysed by means of the linear solvation energy relationship (LSER) concept proposed by Kamlet and Taft. The linear correlation of the absorption maxima with parameters of Kamlet-Taft solvatochrome equation yielded satisfactory results.

Keywords: Solvatochromism, Kamlet-Taft, Azo dyes, LSER.

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UTICAJ RASTVARAČA NA APSORPCIONE SPEKTRE PREHRAMBENIH AZO BOJA 

 

Izvod

Uticaj polarnosti rastvarača na apsorpcione spektre prehrambenih azo boja ispitivan je metodom linearne korelacije energije solvatacije (LSER). U ovu svrhu korišćeno je šest prehrambenih azo boja i to: tartrazin (E 102), ponceau 4R (E 124), azorubin (E 122), brilijant crna (E 151), amarant (E 123) i gelb oranž S (E 110). Apsorpcioni spektri rastvorenih azo boja određeni su u talasnom opsegu vidljivog zračenja, odnosno u opsegu od 380 do 760 nm, u osam rastvarača različite polarnosti. Polarnost samih boja je uticala na izbor malog broja polarnih rastvarača. Spektre ispitivanih azo boja karakteriše jedan apsorpcioni maksimum.  Efekat polarnosti rastvarača i efakat vodoničnog vezivanja rastvarač-rastvorena supstanca ispitivan je primenom Kamlet-Taftove solvatohromne jednačine. Linearna korelacija apsorbcionih maksimuma sa parametrima Kamlet-Taftove solvatohromne jednačine dala je zadovoljavajuće rezultate.

Ključne reči: Solvatohromizam, Kamlet-Taft, Azo boje, LSER.

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Mihailo Mrdak1*, Časlav Lačnjevac2, Marko Rakin3, Darko Veljić4, Nikola Bajić4

1Istraživački i razvojni Centar, IMTEL Komunikacije a.d., Beograd, Srbija, 2Univerzitet u Beogradu, Poljoprivredni fakultet, Beograd, Srbija, 3Univerzitet u Beogradu, Tehnološko-metalurški fakultet, Beograd, Srbija, 4Techno experts d.o.o – Istraživački i razvojni Centar, IHIS, Belgrade, Srbija

Scientific paper

ISSN 0351-9465, E-ISSN 2466-2585
UDC: 546.77:620.198:620.172
doi: 10.5937/zasmat1904336M

Zastita Materijala 60 (4)
336 – 341  (2019)

Characterization of vacuum plasma spray NiCoCrAlY coating resistant to high temperature oxidation

Abstract

Protective vacuum plasma spray VPS – NiCoCrAlY coating is used on sections of gas turbines to allow for longer and more reliable operation of sections exposed to aggressive effects of high temperature oxidation. Depositing of NiCoCrAlY alloy powder was done with the vacuum plasma spray system of the Plasma Technik – AG Companyon the A-2000 control unit using the plasma F4 gun. To test the mechanical properties and microstructure of the NiCoCrAlY coating, the powder was deposited on Č.4171 (X15Cr13 EN10027) steel substrates.To examine the microstructure of the coating in the heat-treated state, the powder was deposited on an IN738LC alloy substrate, which was pre-heated to a temperature of 750 to 800°C before deposition of the powder. The coating with the IN738LC alloy substrate was heat-treated at 1150°C for 2 hours in anargon shielded atmosphere. Mechanical testing of the microhardness of the coating was done using the HV0.3 method and the tensile bond strength using the tension method. The morphology of the powder particles and the morphology of the surface of the deposited coating were examined using a scanning electron microscope (SEM). The microstructure of coating layers in deposited state was tested on an optical microscope (OM). After thermal treatment, etching of the coating was done in the reagent CuSO4 + HCl aqueous solution. Analysis of the microstructure of the coating after etching was performed on the SEM, on the basis of which a score of the quality of the diffusion VPS – NiCoCrAlY coating was given.

Keywords: vacuum plasma spraying process, NiCoCrAY, microstructure, microhardness, tensile bond strength.

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KARAKTERIZACIJA VAKUUM PLAZMA SPREJ PREVLAKE NiCoCrAlY OTPORNE NA VISOKOTEMPERATURNU OKSIDACIJU

Izvod

Zaštitna vakuum plazma sprej VPS – NiCoCrAlY prevlaka se koriste na sekcijama gasnih turbina da bi se omogućio duži i pouzdaniji rad sekcijama izloženim agresivnom napadu visokotemperaturne oksidacije. Deponovanje praha od legure NiCoCrAlY urađeno je vakuum plazma sprej sistemom firme Plasma Technik – AG na upravljačkoj jedinici A-2000 sa plazma pištoljem F4. Za ispitivanje mehaničkih karakteristika i mikrostrukture NiCoCrAlY prevlake, prah je deponovan na substratima od čelika Č.4171 (X15Cr13 EN10027). Za ispitivanje mikrostrukture prevlake u termički obrađenom stanju, prah je deponovan na substratu od legure IN738LC, koji je pre depozicije praha bio predgrejan na temperaturi od 750 do 800°C. Prevlaka je sa substratom od legure IN738LC termički tretirana na 1150°C u trajanju od 2 sata u zaštitnoj atmosferi argona. Mehanička ispitivanja mikrotvrdoće prevlake urađena su metodom HV0.3 i zatezna čvrstoća spoja metodom na zatezanje. Morfologija čestica praha i morfologija površine deponovane prevlake ispitana je na skening elektronskom mikroskopu (SEM). Mikrostruktura slojeva prevlake u deponovanom stanju ispitana je na optičkom mikroskopu (OM). Posle termičke obrade sprovedeno je nagrizanje prevlake u reagensu CuSO4 + HCl vodeni rastvor. Analiza mikrostrukture prevlake posle nagrizanja urađena je na SEM-u, na osnovu čega se dala ocena kvaliteta difuzione VPS – NiCoCrAlY prevlake.

Ključne reči: vakuum plazma sprej proces, NiCoCrAY, mikro struktura, mikro tvrdoća, zatezna čvrstoća spoja.

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Miloš B. Rajković1*, Marija Mitrović2,
Svetlana Antić-Mladenović3

1Univerzitet u Beogradu, Poljoprivredni fakultet, Institut za prehrambenu tehnologiju i biohemiju, Katedra za hemiju i biohemiju, Beograd-Zemun, Srbija, 2MIPHEM d.o.o., Beograd, Srbija, 3Univerzitet u Beogradu, Poljoprivredni fakultet, Institut za zemljište i melioracije, Katedra za agrohemiju i fiziologiju bilja, Beograd-Zemun, Srbija

 

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC:661.77:662.2.035:66.091.3+
doi: 10.5937/zasmat1903229Z


Zastita Materijala 60 (4)
342 – 359  (2019)

 

SECURING TRUST IN THE QUALITY OF RESULTS OF CHEMICAL METHODS EXAMINATION

Securing trust in the quality of examination results is one of the most important segments of the quality management system.

Quality management is the first step in ensuring the quality of analytical procedures and predicts the application of appropriate techniques and procedures in order to fulfill the defined quality requirements with an aim to prevent errors in working process. Activities related to quality management include measures that provide statistical control of accuracy of the examined procedure. These activities describe measures that are used to achieve repeatable and reliable examined results.

In order to achieve the maximum reliability of the examined results, the validity of the conducted examination is controlled from entering the sample in the laboratory until the release of reports of examination, by continuously monitoring and following all the activities of the analytical process, as well as complete documentation of the quality management system. By continuously monitoring the quality of examination results and with continuous improvement of its’ own work procedures through finding mistakes, analyzing the causes of nonconformity, taking preventive and corrective measures, developing its’ own procedures of internal control methods, participating in laboratory comparisons and education of staff, the laboratory provides trust in the quality of examination results, and therefore its’ own competence.

Key words: quality management, validation, PT schemes, control cards

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OBEZBEĐENJE POVERENJA U KVALITET REZULTATA HEMIJSKIH METODA ISPITIVANJA  

Izvod

Obezbeđenje poverenja u kvalitet rezultata ispitivanja jedan je od najvažnijih segmenata sistema menadžmenta kvalitetom.

Upravljanje kvalitetom predstavlja prvi stepen obezbeđenja kvaliteta analitičkih postupaka i predviđa primenu odgovarajućih tehnika i postupaka radi ispunjavanja postavljenih zahteva za kvalitetom sa ciljem sprečavanja nastanka greške/neusaglašenosti u radu. Aktivnosti vezane za upravljanje kvalitetom sadrže mere kojima se postiže statistički nadzor tačnosti ispitivanog postupka, odnosno opisuju mere koje se primenjuju za postizanje ponovljivih i pouzdanih rezultata ispitivanja. U cilju postizanja maksimalne pouzdanosti rezultata ispitivanja, valjanost obavljenih ispitivanja kontroliše se od ulaska uzorka u laboratoriju do samog izdavanja izveštaja o ispitivanju, tako što se kontinualno nadgledaju i prate sve aktivnosti analitičkog procesa, kao i kompletna dokumentacija sistema menadžmenta kvalitetom.

Kontinuiranim praćenjem kvaliteta rezultata ispitivanja i stalnim unapređenjem sopstvenih postupaka rada kroz pronalaženje grešaka/neusaglašenosti, analiziranje uzroka neusaglašenosti, preduzimanja preventivnih i korektivnih mera, razvoj sopstvenih postupaka interne kontrole metoda, učestvovanje u međulaboratorijskim poređenjima, edukaciju osoblja, laboratorija obezbeđuje poverenje u kvalitet rezultata ispitivanja, a samim tim i svoju kompetentnost.

Ključne reči: upravljanje kvalitetom, validacija, PT šema, kontrolne karte

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Dušan Rajić1, Negovan Ivanković2*

1University of Belgrade, Innovation Center, Faculty of Technology and Metallurgy, Belgrade, Serbia,  2University of Defence in Belgrade, Military Academy, Belgrade, Serbia

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC: 614.894.2:66-911.38+620.3
doi:10.5937/zasmat1904360R

Zastita Materijala 60 (4)
360 – 368  (2019)

 

Contributions of impregnated silver nanoparticles to ideality increase of filtration material in human respiratory protection

Abstract

A technical contradiction arises when within a system one parameter improves thus automatically causing another one to worsen. In a situation like this, instead of a usual acceptance of compromise which leads to optimization of a solution for a newly founded problem, in inventology we implement the process of idealisation. The experimental part of this study comprises comparative examination of NaCl aerosol leakage, as a simulator of biological agents, into the epidemiological anti-microbe masks EM1 and EM2, with the aim of determining physiological suitability of EM1 and EM2 and the resistance that arises when inhaling NaCl aerosol was measured at the flows of 95dm3/min. It was experimentally proved that impregnation of silver nanoparticles onto the inner filtrating layer of EM2 contributes to the increase of its efficiency, and mathematical modelling helped calculate the realistic increase of this means.

Keywords: idealisation, mathematical modelling, protective half-masks.

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DOPRINOS IMPREGNISANIH NANOČESTICA SREBRA PORASTU IDEALNOSTI FILTRIRAJUĆIH SREDSTAVA RESPIRATORNE ZAŠTITE 

Izvod

Tehnička kontradikcija se javlja kad se u sistemu poboljša jedan parametar, koji automatski prouzrokuje pogoršanje nekog njegovog drugog parametra. U takvoj situaciji, umesto uobičajenog prihvatanja kompromisa koji vodi ka optimizaciji rešenja nastalog problema, u inventologiji se sprovodi proces idealizacije. Eksperimentalni deo rada je obuhvatao komparativno ispitivanje propuštanja aerosola NaCl, kao simulatora bioloških agenasa, prema unutrašnjosti epidemiološke maske antimikrobne EM1 i EM2. U cilju utvrđivanja fiziološke podobnosti EM1 i EM2, mereni su otpori koji nastaju pri udisanju aerosola NaCl kod protoka od 95 dm3/min. Eksperimentalno je dokazano da impregnacija nanočestica srebra na unutrašnji filtrirajući sloj kod EM2 doprinosi porastu njegove efikasnosti, a matematičkim modelovanjem izračunat je realan porast idealnosti ovog sredstva.

Ključne reči: filtrirajuća polumaska, respiratorna zaštita, biološki aerosoli.

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Muhammed Ernur Akıner*

Akdeniz University, Vocational School of Technical Sciences, Environmental Protection and Control, Antalya, Turkey

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC:631.432+502.171:546.212
doi:10.5937/zasmat1904369E

Zastita Materijala 60 (4)
369 – 378  (2019)

 

Investigating the effects of agricultural best management practices on water quality of a surface water

Abstract

Water is an essential component of the Earth’s ecosystem; each freshwater body has its specific physical and chemical characteristics. High contents of nutrients in the water, such as nitrogen and phosphorus are the major issues in terms of water quality. Notably, excessive nutrient concentrations in surface waters cause eutrophication. This research examines some pollution parameters to determine the current pollution level of the Göksu River. The river passes through the Göksu Delta, which is the most important natural habitat of the Mediterranean region of Turkey. Agricultural best management practices were an important phase of this study. The main goal was to examine the effects of agricultural best management practices on water quality of the Göksu River. Soil and Water Assessment Tool (SWAT) was used for modeling the water quality of the Göksu River considering the agricultural best management practices. Water quality is the lowest in the watershed outlet. For this reason, agricultural best management practices have been evaluated by using SWAT program by considering watershed outlet water quality values. Results confirmed that agricultural best management practices retain large amounts of nutrient load in the Göksu River Watershed. SWAT simulation shows that in case agricultural best management practices were used, there could be a high decrease in BOD5, NO2 and Total P loads. Which means a higher water quality class according to the Surface Water Quality Management Regulations (SWQMR) of Turkey.

Keywords: Best management practices, Göksu Delta, modeling, nutrients, water quality.

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ISPITIVANJE UTICAJA NAJBOLJIH UPRAVLJANJA POLJOPRIVREDNIM PROJEKTIMA NA KVALITET POVRŠINSKE VODE

Izvod

Voda je bitna komponenta ekosistema Zemlje; svako slatkovodno telo ima svoje specifične fizičke i hemijske karakteristike. Visoki sadržaji hranljivih materija u vodi, kao što su azot i fosfor, glavna su pitanja u pogledu kvaliteta vode. Posebno, prekomerne koncentracije hranljivih sastojaka u površinskim vodama uzrokuju eutrofikaciju. Ovo istraživanje ispituje neke parametre zagađenja  da bi se utvrdio trenutni nivo zagađenja reke Goksu. Reka prolazi kroz deltu Goksu, koja je najvažnije prirodno stanište mediteranskog regiona Turske. Najbolje poljoprivredne prakse upravljanja bile su važna faza ove studije. Glavni cilj bio je ispitivanje uticaja najboljih poljoprivrednih praksi upravljanja na kvalitet vode reke Goksu. Alat za procenu tla i vode (SWAT) korišćen je za modeliranje kvaliteta vode reke Goksu uzimajući u obzir najbolje poljoprivredne prakse upravljanja. Kvalitet vode je najniži u slivu. Iz tog razloga, najbolje prakse upravljanja poljoprivredom su ocenjene korišćenjem SWAT programa uzimajući u obzir vrednosti kvaliteta izlazne vode. Rezultati su potvrdili da najbolje poljoprivredne prakse upravljanja zadržavaju velike količine hranjivih sastojaka u vodnom koritu reke Goksu. SWAT simulacija pokazuje da bi u slučaju da se koriste najbolje poljoprivredne prakse upravljanja moglo doći do velikog smanjenja opterećenja BOD5, NO2– i ukupni P. To znači višu klasu kvaliteta vode prema turskim pravilima o upravljanju kvalitetom površinskih voda (SWQMR).

Ključne reči: najbolje prakse upravljanja, Delta Goksu, modeliranje, hranjive materije, kvalitet vode.

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Olga Mocreac*

Technical University of Moldova, Chisinau, Moldova

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC: 621.793.1+546.24
doi:10.5937/zasmat1904379M

Zastita Materijala 60 (4)
379 – 384  (2019)

 

 

Effect of deposition rate and substrate microstructure on gas sensitivity of Te thin films

Abstract

Tellurium thin films have been prepared using different rates (0.1 ÷ 30 nm/s) by physical deposition in vacuum on glassy, sintered alumina and electrochemically nanostructured Al2O3 substrates. The sensitivity to nitrogen dioxide of fabricated films was tested at room temperature. It is shown that the deposition rate strongly influences the microstructure of the films in question, as well as their gas sensing properties. The increasing of deposition rate results in transformation of microcrystalline structure of the film into an amorphous one. Simultaneously, both the gas – sensitivity and the response time decrease. The results are explained in terms of interaction between gas molecule and lone – pair electrons of tellurium atoms.

Keywords: deposition rate, gas sensitivity, response time, substrate, thin film.

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UTICAJ BRZINE DEPOZICIJE I MIKROSTRUKTURE SUBSTRATA NA GASNU  OSETLJIVOST Te – TANKIH FILMOVA 

Izvod

Telur tanke folije pripremljene su korišćenjem različitih brzina (0,1 ÷ 30 nm/s) fizičkim taloženjem u vakuumu na staklu, sinterovanoj glinici i elektrohemijski nanostrukturnim Al2O3 supstratima. Osetljivost proizvedenih filmova na gas azot-dioksid testirana je na sobnoj temperaturi. Pokazano je da brzina taloženja snažno utiče na mikrostrukturu filmova o kojima je reč, kao i na njihova senzorna svojstva prema gasu. Povećanje brzine taloženja rezultira transformacijom mikrokristalne strukture filma u amorfnu. Istovremeno se smanjuje i osetljivost na gas i vreme odziva. Rezultati su objasnjeni u smislu interakcije između molekula gasa i usamljenih elektrona atoma telura.

Ključne reči: brzina taloženja, osetljivost na gas, vreme odziva, supstrat, tanki film.

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