127 research outputs found
Istraživanje i procjena zaostalih naprezanja u plinski naŔtrcanim NiCrBSi slojevima
For thermally sprayed coatings, beside good wear and corrosion resistance there is also a need for a good coating/substrate adhesion, reduced porosity and reduced level of residual stresses. Residual stresses that occur in the substrate/coating system are very significant because their relaxation can cause different coating failures. In this paper, different approaches to investigation of residual stresses in thermally sprayed coatings, have been presented. An analytical model (authors Tsui and Clyne) was used to estimate the distribution of residual stresses in flame sprayed and fused NiCrBSi coatings. These data can be used as input data for the numerical model.Za toplinski naÅ”trcane slojeve, uz dobru otpornost slojeva na troÅ”enje i koroziju, postoje i zahtjevi za dobrom prionjivosti sloja na podlogu,smanjenom poroznosti i smanjenom razinom zaostalih naprezanja. Zaostala naprezanja koja se pojavljuju u sustavu podloga/naÅ”trcani sloj, osobito su važna, jer se njihovom relaksacijom mogu pojaviti razna oÅ”teÄenja sloja. U ovome radu prikazani su pristupi istraživanju zaostalih naprezanja u toplinski naÅ”trcanim slojevima, te je na osnovi analitiÄkog modela (autori Tsui i Clyne) procijenjena raspodjela zaostalih naprezanja za NiCrBSi slojeve nanesene postupkom plinskog naÅ”trcavanja praha s utaljivanjem. Ovi podaci mogu se koristiti kao ulazni podaci za numeriÄki model
ECONOMIC ASPECTS ON SOYBEAN PRODUCTION IN EAST CROATIA
Tijekom dvogodiÅ”njeg razdoblja (2004. i 2005. godine) obavljeno je istraživanje o visini prinosa i ekonomskoj isplativosti proizvodnje tri rane sorte soje (Dubravka 0, Marija 00 i Danica 000) razliÄitih grupa dozrijevanja. Pokusi su postavljeni po split-plot shemi na poljima Zavoda za sjemenarstvo i rasadniÄarstvo iz Osijeka, Kutjevo d.d. i PPK Nova GradiÅ”ka uz primjenu standardne agrotehnike za soju.
Jaz koji nastaje porastom broja stanovnika i istovremenim smanjenjem poljoprivrednih povrÅ”ina iz godine u godinu sve je veÄi, a soja zbog velikog postotka bjelanÄevina (od 35-50%) i ulja (od 18-24%) preuzima vodeÄe mjesto u proizvodnji i ishrani ÄovjeÄanstva. Soja zbog naknadne i postrne sjetve postaje zanimljiva poljoprivrednim proizvoÄaÄima diljem svijeta. UzimajuÄi u obzir agrotehniÄke mjere koje se koriste, uz pomoÄ tablica i grafikona dana je analiza Äimbenika i usporedba isplativosti proizvodnje pojedine sorte soje u Hrvatskoj na povrÅ”ini preko tri hektara, kako bi se odredila najpogodnija sorta za domaÄu poljoprivrednu proizvodnju.During the two vegetation years (2004 and 2005) an examination was conducted on influence of three early breeds of soybean (Dubravka 0, Marija 00 and Danica 000) belonging to different groups of ripening in terms of level of crop yield and cost effectiveness. The tests were undertaken by split-plot scheme on the crop fields originated from Institution for seed and seedlings Osijek, Kutjevo d.d. and PPK Nova GradiÅ”ka using standardized agro measures valid for soybean in The Republic of Croatia.
The difference between increase of the number of inhabitants and decrease in the crop fields area has risen significantly. Soybean, because of its high percentage of proteins (35-50%) and oil (18-24%), slightly for sure overtakes the first position in agricultural production and nutrition of mankind. Soybean is becoming more and more interesting to producers worldwide because of its rich seeding capability. Taking into account the agricultural measures used the analysis and comparison of production effectiveness between each breed of soybean in Croatian on the area more than three ha are presented in tables and graphs. In this way the best breed can be ultimately determined for domestic farm production
Gateway-pathway heritage and urban growth zagreb case study
This paper is a part of on-going research into the typological definition of 'urban gateway-pathways'. This term refers to routes used to connect peripheral settlements to the urban core of contemporary cities. The typology was developed with reference to a sample of 18 Central European cities that were formerly provincial capital cities of the Austro-Hungarian monarchy. This paper provides the first authoritative syntactical description of the city of Zagreb and reports on initial syntactical analysis of its historic pathway typology using the transect method established by Hi II ier (1999). The results from the transect analysis are then used to provide more refined typological descriptions of the gateway-pathways and their historical transformations, and to frame a future phase of research using segment analysis
Axial light emission and Ar metastable densities in a parallel plate dc micro discharge in steady state and transient regimes
Axial emission profiles in a parallel plate dc micro discharge (feedgas:
argon; discharge gap d=1mm; pressure p=10Torr) were studied by means of time
resolved imaging with a fast ICCD camera. Additionally, volt-ampere (V-A)
characteristics were recorded and Ar* metastable densities were measured by
tunable diode laser absorption spectroscopy (TDLAS). Axial emission profiles in
the steady state regime are similar to corresponding profiles in standard size
discharges (d=1cm, p=1Torr). For some discharge conditions relaxation
oscillations are present when the micro discharge switches periodically between
low current Townsend-like mode and normal glow. At the same time the axial
emission profile shows transient behavior, starting with peak distribution at
the anode, which gradually moves towards the cathode during the normal glow.
The development of argon metastable densities highly correlates with the
oscillating discharge current. Gas temperatures in the low current
Townsend-like mode (T= 320-400K) and the high current glow mode (T=469-526K)
were determined by the broadening of the recorded spectral profiles as a
function of the discharge current.Comment: submitted to Plasma Sources Sci. Techno
INFLUENCE OF LOCALITY AND YEAR ON CONTENT OF OIL AND PROTEINS IN SOYBEAN SEED
Tijekom 2004. i 2005. godine obavljena su istraživanja o utjecaju lokaliteta i godine uzgoja na postotak ulja i bjelanÄevina u sjemenu. Ispitivanja su provedena na tri sorte soje - Dubravka, Marija i Danica, razliÄitih grupa dozrijevanja. Pokusi su postavljeni po split-plot shemi na tri lokacije - Zavod za sjemenarstvo i rasadniÄarstvo u Osijeku, Kutjevo d.d. i PPK Nova GradiÅ”ka. Ispitivane sorte pokazale su statistiÄki visoko opravdane razlike (P<0,01) u postotku ulja i bjelanÄevina u sjemenu soje na razliÄitim lokacijama i u razliÄitim godinama ispitivanja. Dobiveni podaci ukazuju na moguÄnost poveÄanja dobiti (veÄim postotkom ulja) u proizvodnji kroz izbor najbolje sorte za pojedinu lokaciju.During two vegetation years, 2004 and 2005, research work was conducted regarding influence of locality and year on oil and protein content in soybean seeds. Research work included soybean varieties - Dubravka, Marija and Danica. Trials were planted in split-plot design, in four replications at three different locations ā Osijek, Kutjevo and Nova GradiÅ”ka.
Results are showing statistically highly important differences (P<0,01) in seed quality for different varieties, different locations and different years. Results also pointing out possibilities for improvement of soybean production with the right choice of variety depending of location condition
Spatiotemporal profile of emission from oscillating dc micro discharges
The axial light distributions in parallel-plate dc microdischarges in argon
show similar behavior to large scale discharges. Between the low-current
Townsend mode and the high current glow mode exists a large region of currents
where different oscillations appear and the dynamic Volt-Ampere characteristic
shows hysteresis behavior. During the oscillations the maximum peak intensity
moves closer to the cathode, which is characteristic for the abnormal glow
regime even though the average current is considerably smaller.Comment: submitted to: IEEE Trans. Plasma Sci., Spec. Issue on Images in
Plasma Sc
A New Metaculus Species (Acari: Eriophyoidea) on Diplotaxis tenuifolia (Brassicaceae) From Serbia: A Combined Description Using Morphology and DNA Barcode Data
A new species of eriophyoid mite, Metaculus diplotaxi n. sp. inhabiting Diplotaxis tenuifolia ( L.) DC., is described from Serbia. To investigate interspecific variability between Metaculus spp. on three different Brassicaceae host plants ( viz. D. tenuifolia, Lepidium latifolium ( L.), Isatis tinctoria ( L.)), we analyzed phenotypic variability of morphological traits and molecular sequences of the mitochondrial cytochrome oxidase subunit I ( MT- CO1). Discriminant analysis identified seven traits that significantly differentiate three Metaculus spp: M. lepidifolii, M. rapistri, and M. diplotaxi n. sp. Analysis of MT- CO1 sequences supported the results obtained from the analysis of morphometric features
Aqueous biphasic systems comprising copolymers and cholinium-based salts or ionic liquids: insights on the mechanisms responsible for their creation
Aqueous biphasic systems (ABS) formed by copolymers and ionic liquids (ILs) have demonstrated to be effective separation platforms, but there is still a gap on the complete understanding of the molecular-level mechanisms ruling the two-phase formation for this type of systems. This work addresses the determination of the liquid-liquid equilibrium of ABS composed of cholinium-based salts or cholinium-based ILs and the triblock copolymer Pluronic PE6200 (PL6200). It is demonstrated that PL6200 can form ABS with all investigated cholinium-based salts or ILs, contrarily to most poly(ethylene)glycol polymers, which is due to the presence of hydrophobic propylene oxide (PO) blocks. From the phase diagrams behavior and IL/salt anions properties, it is shown that the formation of ABS with cholinium-based salts is ruled by the anions polar surface and ability to be hydrated, whereas in systems comprising ILs van der Waals interactions between the copolymer and the IL cannot be discarded. The partition of a series of alkaloids in these systems, namely caffeine, nicotine, theophylline, and theobromine, was additionally appraised. It is shown that caffeine, theophylline, and theobromine preferentially migrate to the more hydrophobic PL6200-rich phase, and that their partition depends on the water content in the respective phase, being ruled by the phasesā hydrophobicity. On the other hand, nicotine, with the most prominent hydrophobic character amongst the studied alkaloids, preferentially migrates to the salt- or IL-rich phase, in which interactions occurring between this alkaloid and the IL/salt cannot be discarded. The ABS formed by cholinium dihydrogenphosphate is the most selective system identified to separate nicotine from the remaining alkaloids, giving some insights into their investigation as separation platforms for alkaloids from natural extracts.publishe
- ā¦