EROZIJA TLA VODOM U UZGOJU RAZLICITIH USJEVA PRI RAZLICITIM ZAHVATIMA OBRADE NA PSEUDOGLEJU SREDISNJE HRVATSKE

Water erosion was recorded during a four-year period (1994-1998.) on Luvic stagnosol (pseudogley), in the Daruvar area (Central Croatia), in different crop development stages according to USLE, under six tillage treatments in growing common arable crops in the common crop sequence. A much higher rate of erosion, higher than Soil loss tolerance (T value) was recorded in the growing of spring crops (row crops) than in winter crops of high plant density, where it was below the T value. In the growing of spring crops, the critical period with maximal water erosion was the period of seedbed preparation (SB period according of USLE), the period just after sowing. In the growing of maize and soybean, this is the period when over 80% of the overall annual erosion occurs in all tillage variants. As expected, the maximal rate of soil erosion, higher than the T value, was recorded in the standard plot according to USLE, followed by the variant of conventional up/down the slope tillage. Soil erosion was much smaller and below the T value in the no-tillage variant and in all variants with tillage across the slope. This means that these variants of soil tillage can be defined as conservation tillage in agroecological conditions of this part of Croatia. In growing winter crops of high density (wheat and oil seed rape), no critical periods were observed and erosion was much below the T value and was uniformly distributed throughout the whole growing season. According to the results, to reduce soil erosion below the T value on slopes of inclination higher than 9%, soil conservation practices are all tillage operations across the slope and/or a reduced crop rotation, without row crops.Tijekom cetvorogodišnjeg razdoblja (1994-98) na pseudogleju središnje Hrvatske pri razlicitim varijantama obrade tla istraživana je erozija tla vodom. U istraživanja su ukljuceni usjevi koji dominiraju u ovom podneblju, dok su varijante obrade slijedece: 1. Standardna parcela prema USLE - crni ugar 2. Konvencionalno oranje (do 25 cm) uz i niz nagib 3. Izostavljanje obrade - izravna sjetva, 4. Konvencionalno oranje okomito na smjer nagiba 5. Vrlo duboko oranje (do 50 cm) okomito na smjer nagiba. 6. Podrivanje na 60 cm dubine + konvencionalno oranje okomito na smjer nagiba. Temeljem polucenih rezultata i odnosa s tolerantnom erozijom za ovaj tip tla zakljucujemo da su erozijski nanosi pri u uzgoju jarina rijetkog sklopa (kukuruz i soja) mnogo veci u odnosu na tolerantno odnošenja za ovaj tip tla. Kriticno razdoblje pri uzgoju ovih kultura je neposredno poslije sjetve ovih usjeva (razdoblje nicanja pa dok usjev nije prekrio 10% površine). U ovom razdoblju utvrdeno je preko 80 % ukupne godišnje erozije, bez obzira na smjer obrade. Pri uzgoju ozimih kultura gustog sklopa (pšenica i uljana repica) nisu zabilježeni kriticna razdoblja, dok je ukupna erozija izrazito niža od tolerantnog odnošenja, pa u obzir dolaze svi istraživani nacini obrade tla. Temeljem svega navedenog zakljucujemo da je obrada uz/niz nagib pri uzgoju jarina rijetkog sklopa visoko rizicna na nagnutim terenima, pa bi taj nacin obrade tla trebalo napustiti. Izostavljanje obrade i bilo koji od nacina obrade okomito na nagib preporucamo za širu primjenu u poljoprivrednoj proizvodnji. Smatramo da je rijec je o nacinima obrade tla koji su u skladu s održivom poljoprivredom u ovom podneblju

EROZIJA TLA VODOM U UZGOJU RAZLICITIH USJEVA PRI RAZLICITIM ZAHVATIMA OBRADE NA PSEUDOGLEJU SREDISNJE HRVATSKE

Water erosion was recorded during a four-year period (1994-1998.) on Luvic stagnosol (pseudogley), in the Daruvar area (Central Croatia), in different crop development stages according to USLE, under six tillage treatments in growing common arable crops in the common crop sequence. A much higher rate of erosion, higher than Soil loss tolerance (T value) was recorded in the growing of spring crops (row crops) than in winter crops of high plant density, where it was below the T value. In the growing of spring crops, the critical period with maximal water erosion was the period of seedbed preparation (SB period according of USLE), the period just after sowing. In the growing of maize and soybean, this is the period when over 80% of the overall annual erosion occurs in all tillage variants. As expected, the maximal rate of soil erosion, higher than the T value, was recorded in the standard plot according to USLE, followed by the variant of conventional up/down the slope tillage. Soil erosion was much smaller and below the T value in the no-tillage variant and in all variants with tillage across the slope. This means that these variants of soil tillage can be defined as conservation tillage in agroecological conditions of this part of Croatia. In growing winter crops of high density (wheat and oil seed rape), no critical periods were observed and erosion was much below the T value and was uniformly distributed throughout the whole growing season. According to the results, to reduce soil erosion below the T value on slopes of inclination higher than 9%, soil conservation practices are all tillage operations across the slope and/or a reduced crop rotation, without row crops.Tijekom cetvorogodišnjeg razdoblja (1994-98) na pseudogleju središnje Hrvatske pri razlicitim varijantama obrade tla istraživana je erozija tla vodom. U istraživanja su ukljuceni usjevi koji dominiraju u ovom podneblju, dok su varijante obrade slijedece: 1. Standardna parcela prema USLE - crni ugar 2. Konvencionalno oranje (do 25 cm) uz i niz nagib 3. Izostavljanje obrade - izravna sjetva, 4. Konvencionalno oranje okomito na smjer nagiba 5. Vrlo duboko oranje (do 50 cm) okomito na smjer nagiba. 6. Podrivanje na 60 cm dubine + konvencionalno oranje okomito na smjer nagiba. Temeljem polucenih rezultata i odnosa s tolerantnom erozijom za ovaj tip tla zakljucujemo da su erozijski nanosi pri u uzgoju jarina rijetkog sklopa (kukuruz i soja) mnogo veci u odnosu na tolerantno odnošenja za ovaj tip tla. Kriticno razdoblje pri uzgoju ovih kultura je neposredno poslije sjetve ovih usjeva (razdoblje nicanja pa dok usjev nije prekrio 10% površine). U ovom razdoblju utvrdeno je preko 80 % ukupne godišnje erozije, bez obzira na smjer obrade. Pri uzgoju ozimih kultura gustog sklopa (pšenica i uljana repica) nisu zabilježeni kriticna razdoblja, dok je ukupna erozija izrazito niža od tolerantnog odnošenja, pa u obzir dolaze svi istraživani nacini obrade tla. Temeljem svega navedenog zakljucujemo da je obrada uz/niz nagib pri uzgoju jarina rijetkog sklopa visoko rizicna na nagnutim terenima, pa bi taj nacin obrade tla trebalo napustiti. Izostavljanje obrade i bilo koji od nacina obrade okomito na nagib preporucamo za širu primjenu u poljoprivrednoj proizvodnji. Smatramo da je rijec je o nacinima obrade tla koji su u skladu s održivom poljoprivredom u ovom podneblju

Lightning Performance Improvement Of 123 kV Line Ston – Komolac By Use Of Line Surge Arresters

This paper presents HEP - Transmission System Operator Ltd. Line surge arrester (LSA) application pilot project on the Ston – Komolac 123 kV line. This 44 km long single circuit shielded transmission line operates in the region with a high lightning activity (keraunic level about 70 thunder days). In addition, it was very difficult to obtain good footing resistance. For these reasons, considered line used to have very bad lightning performance. It was decided to install Line surge arresters for line lightning performance improvement. In order to optimize arrester installation configuration sigma slp software simulations were performed. LSA are installed according to the results of the software simulations. LSA are installed in summer 2007 (110 gapless, IEC-class II Line arresters). Sixty one LSA are equipped with Excount - II monitoring sensors (monitoring arrester leakage current and peak of the impulse current). Based on the 8-month experience, LSA installation has improved line lightning performance. New line performance is close to the targeted once (improvement by 50 to 60 %). Surge arrester monitors collect very interesting information. Collected info will be compared with the software simulations

Applying Research Results to Production Chemistry in the Galapagos Research Center Ltd., Zagreb

Tvrtka Galapagos istraživački centar d. o. o. privatna je znanstvena organizacija, aktivna u područjima kemije, biologije, biomedicine, veterine i farmacije. Za potrebe ovog članka posvećenog Međunarodnoj godini kemije, obuhvaćen je pregled područja kojim se bave kemičari u ovom istraživačkom centru, a iznesene su i tehnike i tehnologije koje se primjenjuju u provedbi istraživačko-razvojnih projekata. Aktivnosti kemičara usmjerene su na sintezu novih organskih spojeva, potencijalnih novih lijekova, na njihovu identifikaciju i strukturnu karakterizaciju, na procese pročišćavanja, uvećanja sinteze (scale up), na primijenjenu analitiku u biološkim materijalima (DMPK - metabolizam lijekova i farmakokinetika) te na farmaceutski razvoj pretkliničkih kandidata. Projektni timovi u Galapagosu obuhvaćaju istraživače svih relevantnih struka za istraživanje potencijalnih novih lijekova, kao što su kemičari (kemijski inženjeri i tehnolozi), biolozi, medicinari, veterinari, farmaceuti. Konačni cilj svakog od projekata je djelotvoran, dobro definiran pretklinički kandidat, koji se dalje razvija u suradnji s drugim dijelovima Galapagosa (Belgija, Francuska, Velika Britanija) ili u partnerstvu s velikim farmaceutskim kompanijama. U članku su područja istraživanja i tehnologije potkrijepljeni konkretnim primjerima i rezultatima objavljenim u člancima.Galapagos Research Center Ltd., is a private research organization, active in the field of chemistry, biology, biomedicine, veterinary science and pharmacy. This article is devoted to the International Year of Chemistry; this review includes the areas of study undertaken by the chemists in the research center. Also presented are the current techniques and technologies applied in the implementation of research and development projects. The main activities of chemists are directed to the synthesis of new organic compounds resulting in potentially new medicines, their subsequent identification, structural characterization, purification process, magnification (scale up), the applied analysis of biological materials (DMPK – Drug Metabolism and Pharmacokinetics) and the pharmaceutical development of preclinical candidates. Project teams at Galapagos incorporate researchers of all relevant professions to explore the potential of new medicines. These include chemists (chemical engineers and technologists), biologists, medical doctors, veterinarians and pharmacists. The ultimate goal of each of the projects is to establish an effective, well-defined preclinical candidate, which is further developed in other parts of the organization (Belgium, France, Great Britain), otherwise in the development laboratories of large partner organizations. This research article includes research and technology supported by concrete examples, and the results published in previous articles

Regional spreading of paleo-gravel formations in north-western Croatia and their geomorphological importance for explantion of morphogenesis and neotectonical movements

U ovom se članku obrađuje regionalna distribucija kvartarnih šljunčanih naslaga u dijelu sjeverozapadne Hrvatske, kao i njihovovo geomorfološko značenje u tumačenju morfogeneze reljefa i kvartarnih neotektonskih pokreta.Regionally distributed Quaternary fluvial gravel layers in North-western Croatia, which were by neotectonic movements subsequently removed at different hypsometrical levels, are discussed in the paper