Unlike the conventional calculation models of the hardness, a carburizing-quenching hardness model considers the influence of the carbon content on the phase transformation and hardness. The volume ...fraction model (VFM) and Jominy curve model (JCM) for calculating carburizing-quenching hardness of 20CrNi2Mo steel were built in this study, and the models were used to calculate the hardness of Jominy and gear samples. The hardness results of both models were compared, and the simulation results were verified with the corresponding test results. The results show that the hardness values obtained with both models have a certain calculation accuracy. But due to considering the influence of residual austenite (RA) on the hardness, the simulation accuracy of the VFM was better for the low Jominy distance and the hardened case, while the simulation accuracy of the JCM was better for the large Jominy distance and the low-carbon martensite region; the calculation of the latter is more convenient and its accumulated error is small.
Salinity is one of the biggest limiting factors for agriculture in semi-arid areas of the world. For this reason, an experiment was conducted to study the effect of seed priming with NaCl and CaCl
on ...growth and yield responses of Tunisian coriander cultivar exposed to five levels of salinity (0, 2, 4, 6, 8 g l
). Seeds of coriander were primed with aerated solutions of 0.13 M NaCl and CaCl
for 24 h. Results indicated that with increasing salinity, emergence traits (total emergence, mean emergence time), growth parameters (plant height, shoot fresh and dry weight) and mineral contents (K
and Ca
) decreased, but to a less degree in primed seeds. In all of the salinity levels, primed seeds possessed higher emergence and growth rate than control. However, further studies are needed to highlight the effect of seed priming on yield and oil content of coriander under salt stress.
Slanost je eden izmed največjih omejevalnih dejavnikov kmetijstva v polsušnih območjih sveta. V ta namen je bil izveden poskus za preučevanje učinkov predtretiranja semen z NaCl in CaCl
sorte tunizijskega koriandra na parametre rasti in pridelka, ki je bila izpostavljena petim stopnjam slanosti (0, 2, 4, 6, 8 g l
). Semena koriandra so bila tretirana s prezračeno raztopino 0.13 M NaCl in CaCl
za 24 h. Izsledki so pokazali, da so z naraščajočo slanostjo parametri vznika (totalni vznik, poprečni čas vznika), rasti (višina rastlin, sveža in suha masa poganjkov) in vsebnosti hranil (K
in Ca2
) upadli, vendar manj pri predhodno tretiranih semenih. Predhodno tretirana semena so imela pri vseh stopnjah slanosti boljši vznik in večjo rast kot kontrola. Za preučitev učinka predtretiranja s solmi na pridelek in vsebnost olj koriandra v razmerah solnega stresa so potrebne še nadaljne raziskave.
Uvod: Glavni namen raziskave je bil ugotoviti razpoložljivost natrija v kupljenih živilih v Sloveniji. Osnovo so predstavljali podatki nacionalne raziskave o porabi v gospodinjstvih za obdobje ...2000-2009. Sekundarni cilj raziskave je bil ugotoviti, katere skupine živil prispevajo k največji razpoložljivosti natrija v prehrani slovenskih porabnikov.
The basic parameter of re-introduction of this crop into the crop rotation in Slovenia is testing and trials of sunflower cultivars (Helianthus annuus L.), that could be suitable for the growing ...conditions in Slovenia, for the purpose of organic production and for the production of healthy food for consumers. On the experimental field at Biotechnical Faculty, in the period from 2002 to 2006, we were testing certain economically significant properties of five sunflower cultivars: Kernal, Kongo, Delija, Goleador and Iregi szürke csíkos. Seeds were sown by hand to the parcel in the size of 3 m x 11.8 m. Under the growing conditions in central Slovenia the genetic potential of hybrids for the production above 4 t of seed/ha was almost reached and closely approached by the hybrids Kongo and Kernal with average yields 3.5 t/ha and 3.3 t/ha. Yields of Delija and Goleador hybrids were about 1 to 1.2 tons lower, but mutually comparable. The lowest yield (1.6 t/ha) was given by Iregi szurke csikos variety, which is mostly grown by the producers in Slovenia, mainly because it is used and sold as a bird feed. In the year 2003, the fat content in the seed obtained from the hybrids, reached from 38 to 42 %, for Iregi szurke csikos variety it was only 33 %, on the other side - in the year 2005 - the fat content in the seed obtained from the hybrids was higher, that is 39 to 45 %, and for the Iregi szurke csikos variety the average was the same as in the year 2003. The highest fat content in the seed was reached by highly oleic hybrid Goleador, that is 42 % in the year 2003 and 45 % in 2005; for this hybrid, during this two years of the trials the 78- to 79-percent content of oleic acid in the oil was a little lower than its genetic potential, which is above 80 %. Regarding the use of the crop - for the cold pressed oil - the most important cultivars are the highly oleic hybrid Goleador and semioleic Delija, and for the bird feed instead of the Iregi szurke csikos variety we could sow Kongo and Kernal hybrids, not only due to their higher yields, but also due to higher fat content. Experts can advise producers how they can increase their production of seeds and oil only on the basis of tested, high quality and accessible sunflower assortment.
Preizkušanje kultivarjev sončnice (Helianthus annuus L.), ki bodo ustrezali rastnim razmeram v Sloveniji, potrebam sonaravne pridelave in potrošnikom zdrave hrane, je temelj ponovnega uvajanja te poljščine v kolobar. Na poskusnem polju Biotehniške fakultete smo v obdobju 2002 do 2006 preučevali nekatere gospodarsko pomembne lastnosti petih kultivarjev sončnice: Kernal, Kongo, Delija, Goleador in Iregi szürke csíkos. Seme smo posejali ročno na parcelo velikosti 3 m x 11,8 m. Genskemu potencialu hibridov za pridelek nad 4 t semena/ha sta se v rastnih razmerah osrednje Slovenije najbolj približala hibrida Kongo in Kernal s povprečnima pridelkoma 3,5 t/ha in 3,3 t/ha. Pridelek hibridov Delija in Goleador je bil za 1 do 1,2 toni manjši, vendar med seboj primerljiv. Najmanjši pridelek je dala sorta Iregi szurke csikos (1,6 t/ha), ki jo pridelovalci sončnice v Sloveniji sejejo največ, ker je v prodaji za krmo ptic. Vsebnost olja v semenu v letu 2003 je bila pri hibridih od 38 do 42 %, pri sorti Iregi szurke csikos pa le 33 %, nasprotno pa je bila oljnatost semena v letu 2005 pri hibridih večja, to je 39 do 45 %, pri sorti Iregi szurke csikos pa približno enaka kot v letu 2003. Največjo vsebnost olja v semenu je imel visoko oleinski hibrid Goleador, in sicer 42 % v letu 2003 in 45 % v letu 2005; 78- do 79- odstotna vsebnost oleinske kisline v olju pa je bila v obeh letih nekoliko manjša od njegovega genskega potenciala za to lastnost, ki je nad 80 %. Glede na namen uporabe pridelka sta za hladno stisnjeno olje najprimernejša visoko oleinski hibrid Goleador in pol oleinski Delija, za krmo ptic pa bi lahko namesto sorte Iregi szurke csikos sejali hibrida Kongo in Kernal, ne le zaradi večje rodnosti, ampak tudi zaradi večje vsebnosti maščob. Le na podlagi preizkušenega, kakovostnega in dostopnega sortimenta sončnice bodo lahko strokovnjaki svetovali pridelovalcem, tako, da bodo ti pridelali več semena in maščob.
V letu 1997 smo na različnih parcelah iste površine v štirih košnjah in v različnih razvojnih fazah rastlin zbrali po 10 vzorcev črne detelje (Trifolium pratense) in mnogocvetne ljuljke (Lolium ...multiflorum) ter po 8 vzorcev mačjega repa (Phleum pratense), trpežne ljuljke (Lolium perenne), travniške bilnice (Festuca pratensis), rdeče bilnice (Festuca rubra) in pasje trave (Dactylis glomerata). Največjo povprečno vsebnost mangana v suhi snovi smo ugotovili v vzorcih pasje trave (215,3 ± 54,9 mg kg-1 SS) in v vzorcih rdeče bilnice (55,7 ± 7,8 mg kg-1 SS). Druge trave in črna detelja so vsebovale statistično značilno manj mangana v suhi snovi (od 33,1 mg do 42,0 mg kg-1 SS). Pri travah z manjšo vsebnostjo mangana in pri črni detelji je bila ob prvi košnji vsebnost mangana največja v fazi bilčenja (25,2 mg do 61,6 mg kg-1 SS) in najmanjša v fazi cvetenja (16,6 mg do 47,8 mg kg-1 SS). Pri pasji travi pa je vsebnost mangana v suhi snovi z zorenjem rastline v prvi košnji naraščala (od 145,5 mg na 179,5 mg kg-1 SS). Najmanjša povprečna koncentracija mangana je bila pri vseh travah in pri črni detelji v vzorcih prve košnje (od 21,0 mg do 53,0 mg kg-1 SS) in največja jeseni ob četrti košnji (od 42,2 mg do 68,7 mg kg-1 SS), pri pasji travi pa je bila ob prvi košnji 160 mg, ob drugi 272,0 mg in se je v tretji in četrti košnji zmanjšala na 209,6 mg oziroma 215,4 mg kg-1 SS.
V prispevku navajamo pregled literature o vsebnosti, kemični sestavi in strukturi derivatov cimetne kisline, predvsem p-kumarne (PKK) in ferulne kisline (FK) ter lignina, njihovo porazdelitev v ...rastlinah in znotraj rastlinske celične stene. Opisane so tudi povezave lignina in derivatov cimetne kisline z različnimi strukturnimi ogljikovimi hidrati ter osnovne značilnosti strukturno in kemično spremenjenega lignina pri mutantih z rjavo osrednjo žilo (brown midrib; BMR) in mutantih z lomljivim steblom (brittle culm).
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