Change of Pressing Chamber Conicalness at Briquetting Process in Briquetting Machine Pressing Chamber

In this paper, we will present the impact of the conical shape of a pressing chamber, an important structural parameter. Besides the known impact of the technological parameters of pressing chambers, it is also very important to pay attention to their structural parameters. In the introduction, we present a theoretical analysis of pressing chamber conicalness. An experiment aimed at detecting this impact was performed at our institute, and it showed that increasing the conicalness of a pressing chamber improves the quality of the final briquettes. The conicalness of the pressing chamber has a significanteffect on the final briquette quality and on the construction of briquetting machines. The experimental findings presented here show the importance of this parameter in the briquetting process

Testiranje novih supstrata u proizvodnji rasada bosiljka (Ocimum basilicum L.)

The aim was to test new substrates in pot basil nursery plant production. Substrates were prepared using domestic peat from the village of Gaj adding mature manure and fertilizers in various proportions. Eleven substrates were tested. Peat (100%) was the control variant. Manure amounts of 10-15 vol % were added to the remaining variants. Fertilizer formulations 20:20:20 + Me at the following rates 1.25; 1. 85; 2.50; 3. 12 and 3.75 g/l were added to peat. The nursery plants obtained were of excellent quality. The best basil nursery plant quality was obtained using substrates with the manure share of 30 vol% but also with the 1.3 g fertilizer variant.Cilj rada je testiranje novih supstrata u proizvodnji rasada bosiljka u saksijama. Supstrati su pripremljeni od domaćeg treseta iz Gaja uz dodatak stajnjaka i mineralnog đubriva u različitim odnosima. Ispitano je ukupno 11 supstrata. Kontrolna varijanta bila je sam treset (100%). U ostalim varijantama je dodavan stajnjak u količini 10-50 vol%. Tresetu je dodavano i mineralno đubrivo formulacije 20:20:20 + mikroelementi u dozama 1,25; 1,85; 2,50; 3,12 i 3,75 g/l. Dobijen je rasad odličnog kvaliteta. Ispitivanja su pokazala da se najbolji kvalitet rasada bosiljka dobija na supstratima u kojima udeo stajnjaka iznosio 30 vol% i kod varijanti sa upotrebom mineralnog đubriva u dozi od 1,25g

Primena oplemenjenog domaćeg treseta u kontejnerskoj proizvodnji rasada bosiljka

The effect of various substrates in the production of basil seedlings was studied. Peat, originating from Gaj in South Banat, was the predominant component of the studied substrates. Peat was improved by adding different ratios of manure and water soluble mineral fertiliser. The gained result show that the best quality basil seedlings in the container production were obtained with the application of substrates in which the share of manure was 30 vol%. Among different dosages of used water soluble fertilizers, the 1.3 g L-1 dose had the best effect on the quality of basil seedlings. The obtained results are significant for the application and improvement of local peat as the main component in the production of seedlings of medicinal, aromatic and seasoning herbs in Serbia. .Ispitivan je uticaj različitih supstrata u proizvodnji rasada bosiljka. Dominantna komponenta ispitivanih supstrata je domaći treset, koji je oplemenjen dodavanjem stajnjaka i vodorastvorljivog mineralnog đubriva u različitim odnosima. Rasad bosiljka je proizveden u kontejnerima po speedling sistemu. Istraživanja su pokazala da se najbolji kvalitet rasada bosiljka u kontejnerskoj proizvodnji dobija na supstratima u kojima je udeo stajnjaka iznosio 30 vol%. Od upotrebljenih različitih doza vodorastvorljivog đubriva, doza od 1,3 g/l je ostvarila nabolji efekat na kvalitet rasada bosiljka. Dobijeni rezultati istraživanja imaju značaj u primeni i promociji domaćeg treseta kao glavne komponente supstrata namenjenih proizvodnji rasada lekovitog, aromatičnog i začinskog bilja u Srbiji.

Pre-Processing of Point-Data from Contact and Optical 3D Digitization Sensors

Contemporary 3D digitization systems employed by reverse engineering (RE) feature ever-growing scanning speeds with the ability to generate large quantity of points in a unit of time. Although advantageous for the quality and efficiency of RE modelling, the huge number of point datas can turn into a serious practical problem, later on, when the CAD model is generated. In addition, 3D digitization processes are very often plagued by measuring errors, which can be attributed to the very nature of measuring systems, various characteristics of the digitized objects and subjective errors by the operator, which also contribute to problems in the CAD model generation process. This paper presents an integral system for the pre-processing of point data, i.e., filtering, smoothing and reduction, based on a cross-sectional RE approach. In the course of the proposed system development, major emphasis was placed on the module for point data reduction, which was designed according to a novel approach with integrated deviation analysis and fuzzy logic reasoning. The developed system was verified through its application on three case studies, on point data from objects of versatile geometries obtained by contact and laser 3D digitization systems. The obtained results demonstrate the effectiveness of the system

SHAPE OF PRESSING CHAMBER FOR WOOD BIOMASS COMPACTING

The main goal of this contribution is to present results of analyse of mathematical models of wood biomass compacting. Doesn't exist a lot of models which describes real state in pressing chamber and amount of factors impact at compacting process and thereby on briquette quality. According to our suggestion have also constructional parameters of pressing chamber (pressing spout and pressing ram) expressive impact on result briquette quality. We did theoretical analyses which showed us that impact on briquette quality have also change of pressing chamber length, change of friction coefficient, change of pressing chamber conicalness and also change of pressing chamber diameter

Usporedna analiza modela dva tipa elemenata za stezanje u dinamičkim uvjetima

This paper studies the compliance of the fixture-workpiece system. Workpiece clamping case with two types of clamping elements is considered. The first type of clamping element is standard, with flat top, while the second one is specially designed, with round cutting insert. Analyzed was the case of workpiece clamping using small forces, whereby the deformations in the workpiece/clamping element interface are predominantly on the order of magnitude of roughness height. A comparative analysis of dynamic behaviour of both types of clamping elements is also presented. In comparison with its standard counterpart, the specially designed clamping element with round cutting insert has superior clamping performance regarding both tangential load capacity and compliance.U radu se razmatra popustljivost sustava naprava-izradak. Razmatra se slučaj stezanja izratka s dva tipa elemenata za stezanje. Prvi tip elementa za stezanje je sa standardnim ravnim čelom. Drugi tip elementa za stezanje je specijalne izvedbe s čelom u obliku kružnog klina. Analiziran je slučaj stezanja malim vrijednostima sila stezanja pri čemu se deformacije u zonama kontakta između elemenata za stezanje i izratka pretežno odvijaju u zonama visine neravnina. Također je prikazana komparativna analiza, predhodno spomenuta, dva načina stezanja izradaka u uvjetima dinamičkih opterećenja. Specijalno dizajnirani element za stezanje s čelom oblika kružnog klina u odnosu na standardni element za stezanje s ravnim čelom ima izrazito veću steznu učinkovitost po pitanju tangencijalne nosivosti i popustljivosti

The most common isolates from pleural infections

Isolation and identification of the pathogens are important for appropriate treatment of pleural infections. Distribution of the most frequent causative agents varies throughout the world and may change in time.The objective of the study is to analyze the bacteriological isolates of pleural fluids in order to identify the most frequent infectious agents and assess their variability in time.The retrospective study included 272 patients with positive pleural fluid samples analyzed in 5-year period. The samples were examined using the conventional microbiological technique.Of 315 bacterial isolates the most common were streptococcal species, 105 (33%), of which 55 (17.3%) represented the Streptococcus milleri group. Gram-positive anaerobic cocci were detected in 56 (17.6%) isolates. Enterobacteriaceae family included 27 (8.5%) isolates and Pseudomonas aeruginosa was registered in 13 (4.1%). No statistically significant difference was registered in pathogen distribution in the examined period (p = 0.288).The most common agents of community-acquired pleural infections are the Streptococcus milleri group and anaerobic Gram-positive cocci. They differ from the most common pathogens of pneumonia. Among the hospital-acquired pleural infections, Pseudomonas species, Staphylococcus aureus and enterobacteria prevail. The distribution of bacterial agents isolated in the 5-year period exhibits no significant differences