Utjecaj zamjene koncentrata na farmi krava muzara

The purpose of the research was to establish the effect of concentrates A (C-A) and B (C-B) on the quantity and composition of the produced milk of dairy cows. The research included cows of Holstein Friesian and Simmental breeds and crossbreeds with Simmental breed. The test took place in two periods. The first period with the C-A lasted from December 2004 to February 2005 and included 113 cows. During the second period the C-B was fed. The test endured from April to June 2005. The results of monthly controls of milk quantity and protein and fat contents were entered into the Excel programme and processed with the statistical programme SPSS for Windows 12.0. When the concentrate B was fed, the milk quantity amounted to 21.99 L/day and was statistically significantly (P<0.05) greater than the milk quantity in case of feeding the concentrate A, when the milk quantity was 19.12 L/day. No statistically significant differences (P<0.05) of the protein and fat content in the milk were established.Željeli smo utvrditi utjecaj koncentrata A i B na količinu i sastav namuzenog mlijeka krava muzara. U istraživanje smo uključili krave holštajnsko-frizijske i simentalske pasmine te križance sa simentalskom pasminom. Pokus smo proveli u dva razdoblja. Prvo razdoblje s koncentratom A trajalo je od prosinca 2004. do veljače 2005. sa 113 uključenih krava. U drugom razdoblju s koncentratom B pokus je realiziran od travnja do lipnja 2005. Dobivene rezultate za količinu mlijeka, sadržaj proteina i masti kod svake mjesečne kontrole stavili smo u Excel te ih statistički obradili pomoću SPSS for Windows 12.0. Količina mlijeka iznosila je uz hranidbu koncentrata B 21,99 L/dan i bila je statistički signifikantno (P<0,05) veća od količine mlijeka kod primjene koncentrata A, gdje je iznosila 19,12 L/dan. Kod sadržaja proteina i masti u mlijeku nismo utvrdili statistički signifikantnih razlika (P<0,05)

Effect of concentrate exchange on dairy farm

The purpose of the research was to establish the effect of concentrates A (C-A) and B (C-B) on the quantity and composition of the produced milk of dairy cows. The research included cows of Holstein Friesian and Simmental breeds and crossbreeds with Simmental breed. The test took place in two periods. The first period with the C-A lasted from December 2004 to February 2005 and included 113 cows. During the second period the C-B was fed. The test endured from April to June 2005. The results of monthly controls of milk quantity and protein and fat contents were entered into the Excel programme and processed with the statistical programme SPSS for Windows 12.0. When the concentrate B was fed, the milk quantity amounted to 21.99 L/day and was statistically significantly (P<0.05) greater than the milk quantity in case of feeding the concentrate A, when the milk quantity was 19.12 L/day. No statistically significant differences (P<0.05) of the protein and fat content in the milk were established

Utjecaj zamjene koncentrata na farmi krava muzara

The purpose of the research was to establish the effect of concentrates A (C-A) and B (C-B) on the quantity and composition of the produced milk of dairy cows. The research included cows of Holstein Friesian and Simmental breeds and crossbreeds with Simmental breed. The test took place in two periods. The first period with the C-A lasted from December 2004 to February 2005 and included 113 cows. During the second period the C-B was fed. The test endured from April to June 2005. The results of monthly controls of milk quantity and protein and fat contents were entered into the Excel programme and processed with the statistical programme SPSS for Windows 12.0. When the concentrate B was fed, the milk quantity amounted to 21.99 L/day and was statistically significantly (P<0.05) greater than the milk quantity in case of feeding the concentrate A, when the milk quantity was 19.12 L/day. No statistically significant differences (P<0.05) of the protein and fat content in the milk were established.Željeli smo utvrditi utjecaj koncentrata A i B na količinu i sastav namuzenog mlijeka krava muzara. U istraživanje smo uključili krave holštajnsko-frizijske i simentalske pasmine te križance sa simentalskom pasminom. Pokus smo proveli u dva razdoblja. Prvo razdoblje s koncentratom A trajalo je od prosinca 2004. do veljače 2005. sa 113 uključenih krava. U drugom razdoblju s koncentratom B pokus je realiziran od travnja do lipnja 2005. Dobivene rezultate za količinu mlijeka, sadržaj proteina i masti kod svake mjesečne kontrole stavili smo u Excel te ih statistički obradili pomoću SPSS for Windows 12.0. Količina mlijeka iznosila je uz hranidbu koncentrata B 21,99 L/dan i bila je statistički signifikantno (P<0,05) veća od količine mlijeka kod primjene koncentrata A, gdje je iznosila 19,12 L/dan. Kod sadržaja proteina i masti u mlijeku nismo utvrdili statistički signifikantnih razlika (P<0,05)

Use of waste plastics for the preparation of adhesives for wood bonding

Odpadne plastike je čedalje več, zato poskušamo najti različne načine njenega recikliranja in ponovne uporabe. Reciklirani termoplastični polimeri predstavljajo zanimiv potencial za izdelavo lepil, zato je bil cilj naše preliminarne raziskave proučiti primernost odpadnega polistirena za izdelavo lepil za lepljenje lesa. Lepilne mešanice smo izdelali tako, da smo odpadne polistirenske lončke (L) in žličke (Ž) za kavo razrezali na manjše koščke in jih ločeno raztopili v 5 različnih topil: butil acetat (BA), dimetilformamid (DMF), tetrahidrofuran (THF), limonen (L) in aceton (AC). Z njimi smo izdelali lepljence iz dveh bukovih lamel (Fagus sylvatica L.), ki smo jih 10 minut stiskali v hidravlični stiskalnici pri temperaturi 150 °C in tlaku 12 barov. Za ugotavljanje kakovosti zlepljenosti smo izvedli strižni preizkus z univerzalnim testirnim strojem Zwick/Roell Z005. Ugotovili smo, da so preizkušanci, zlepljeni z lepilno mešanico Ž-DMF, dosegli povprečno strižno trdnost 6,5 N/mm2, preizkušanci, zlepljeni z L-DMF, pa 3,8 N/mm2. Vsi ostali preizkušanci so izkazovali nižjo trdnost lepilnega spoja oziroma so večinoma razpadli že po vročem stiskanju ali kasneje med žaganjem v preizkušance. V nadaljnjih raziskavah bomo obetajoči lepilni mešanici modificirali in optimizirali parametre stiskanja z namenom doseganja kakovosti zlepljenosti, ki ustreza standardnim zahtevam za plastomerna lepila za notranjo uporabo.There is more and more plastic waste, so we try to find different ways to recycle and reuse it. Recycled thermoplastic polymers represent an interesting potential for the production of adhesives, so the aim of our preliminary investigations was to examine the suitability of waste polystyrene for the production of adhesives for wood bonding. The adhesive mixtures were prepared by cutting the waste polystyrene cups (L) and coffee spoons (Ž) into smaller pieces and dissolving them separately in 5 different solvents: Butyl acetate (BA), Dimethylformamide (DMF), Tetrahydrofuran (THF), Limonene (L) and Acetone (AC). From these we prepared composite samples of two beech lamellae (Fagus sylvatica L.), which were pressed for 10 minutes in a hydraulic press at a temperature of 150 °C and a pressure of 12 bar. In order to determine the quality of the bonding, we carried out a shear test with a Zwick/Roell Z005 universal testing machine. We found that the test specimens bonded with the adhesive mixture Ž-DMF achieved an average shear strength of 6.5 N/mm2 and the test specimens bonded with L-DMF achieved 3.8 N/mm2. All other test specimens showed a lower strength of the adhesive bonds, or they mostly delaminated after hot pressing or later during sawing into test specimens. In further research work we will modify these promising adhesive mixtures and optimize the pressing parameters in order to achieve bonding quality that meets the standard requirements for thermoplastic adhesives for interior applications