The Relevance of GHG Emissions from Motor Vehicles

The Earth\u27s atmosphere contains not more than 2% of greenhouse gases (GHG), and only 3.4% of them are produced by human activities. GHG emissions from road transport amount to less than 0.3 % of global GHG emissions. In spite of that, even in the Kyoto Protocol, road transport is pointed out as one of the most important targets when the global GHG emission reduction is concerned. In April 2009, the European Commission adopted the regulation (EC) 443/2009, setting CO2 emission performance standards for new passenger cars. The paper briefly describes the global economic impact of the Kyoto Protocol on developing countries. Then, total GHG emissions of various types of vehicles are reviewed, and the emerging vehicle technologies, focusing on reducing GHG emissions and replacing fossil fuels with alternative energy resources, are discussed. A well-to-wheel (WTW) analysis of a midsize electric car operating in Croatia has been carried out in the case study. Finally, the main conclusions are drawn: further reduction in GHG emissions from road transport would result in marginal global effects and, compared to all new power train systems, internal combustion engine running on fossil fuels still has great potential for further improvements thus remaining the most viable solution for the future

Model detonantnoga izgaranja u Ottovom motoru

Detonantno izgaranje je nepoželjna pojava u Ottovom motoru koja nastaje uslijed naglog izgaranja još neizgorjele smjese ispred napredujuće fronte plamena, a visokofrekventne oscilacije tlaka koje pri tome nastaju mogu uništiti motor. Dosadašnjim istraživanjima navedene pojave utvrđeno je da do zapaljenja neizgorjele smjese najčešće dolazi uslijed samozapaljenja njenih vrućih dijelova. Razvojem modela za predviđanje pojave detonantnog izgaranja za 1-D/0-D proračunski model Ottovog motora u kojemu je modelirana temperaturna nehomogenost neizgorjele zone omogućiti će se simuliranje pojava vrućih mjesta u neizgorjeloj smjesi i točnija procjena intenziteta tlačnih oscilacija nastalih detonantnim izgaranjem. Osnova za razvoj i validaciju novog modela su postojeći 3D-CFD rezultati raspodjele temperature u neizgorjeloj smjesi i niz eksperimentalnih podataka o profilu tlaka u cilindru eksperimentalnog CFR motora (engl. Cooperative Fuels Research)

THE RELEVANCE OF GHG EMISSIONS FROM MOTOR VEHICLES

The Earth\u27s atmosphere contains not more than 2% of greenhouse gases (GHG), and only 3.4% of them are produced by human activities. GHG emissions from road transport amount to less than 0.3 % of global GHG emissions. In spite of that, even in the Kyoto Protocol, road transport is pointed out as one of the most important targets when the global GHG emission reduction is concerned. In April 2009, the European Commission adopted the regulation (EC) 443/2009, setting CO2 emission performance standards for new passenger cars. The paper briefly describes the global economic impact of the Kyoto Protocol on developing countries. Then, total GHG emissions of various types of vehicles are reviewed, and the emerging vehicle technologies, focusing on reducing GHG emissions and replacing fossil fuels with alternative energy resources, are discussed. A well-to-wheel (WTW) analysis of a midsize electric car operating in Croatia has been carried out in the case study. Finally, the main conclusions are drawn: further reduction in GHG emissions from road transport would result in marginal global effects and, compared to all new power train systems, internal combustion engine running on fossil fuels still has great potential for further improvements thus remaining the most viable solution for the future

Comparative Energy Consumption Analysis of the Hybrid Diesel Train and the Hybrid Fuel Cell Train

This paper compares train energy consumption of hybrid diesel-electric multiple unit (HDEMU) to hydrogen fuel-cell multiple unit (HFCMU). In the simulation, the parameters of the DMU HŽ7022 train were used for the train model created in Matlab/Simulink environment. Since the train is powered by three diesel engines in original design, it was hybridized by removing one engine and adding a battery and a supercapacitor. For comparison, a train model was made with fuel cells that have rated power of two existing diesel engines, and it was hybridized with a battery and a supercapacitor, as in the simulation with the hybridization of diesel engines. The results are presented by comparing energy consumption for both trains. In addition, voltages, electric current values and power loads of power sources are shown. As the sustainability of the system, the SOC (State of Charge) values of both the battery and the supercapacitor are presented

Enantiomeri kinuklidin-3-ol derivata: Razdvajanje enantiomera i interakcija s ljudskim kolinesterazama

The (R)- and (S)-enantiomers of quinuclidin-3-ol and quinuclidin-3-yl acetate as well as their quaternary N-methyl and N-benzyl derivatives were synthesized in order to study the stereoselectivity of human erythrocyte acetylcholinesterase (EC 3.1.1.7) and plasma butyrylcholinesterase (EC 3.1.1.8). The compounds were tested as substrates and inhibitors of cholinesterases. Both cholinesterases hydrolyze the derivatives of quinuclidin-3-yl acetate with a preference for the (R)- over (S)-enantiomers. In contrast to the hydrolysis of the enantiomers of acetates, the inhibition of acetylcholinesterase and butyrylcholinesterase by the (R)- and (S)-enantiomers of quinuclidin-3-ol derivatives does not reveal enantiomeric preference of the enzymes. The (R)- and (S)-acetates also act as nonstereoselective inhibitors of the enzyme-induced hydrolysis of acetylthiocholine. The best substrate is (R)-N-methyl-3-acetoxyquinuclidinium iodide with kcat = 1.5 x 106 min–1 and kcat = 5.5 x 104 min–1 for acetylcholinesterase and butyrylcholinesterase, respectively. The (R)- and (S)-N-benzylquinuclidinium derivatives are the most potent inhibitors of both enzymes.Priređeni su (R)- i (S)-enantiomeri kinuklidin-3-ola i kinuklidin-3-il-acetata te odgovarajući kvaterni N-metilni i N-benzilni derivati kako bi se proučila njihova interakcija s ljudskom eritrocitnom acetilkolinesterazom (EC 3.1.1.7) i butirilkolinesterazom iz plazme (EC 3.1.1.8). Spojevi su studirani kao supstrati i inhibitori tih enzima. Obje kolinesteraze pokazuju visoku stereoselektivnost pri hidrolizi kinuklidin-3-il acetata preferirajući (R)- u odnosu na (S)-enantiomere. Nasuprot hidrolizi enantiomera acetatnih derivata, inhibicija acetilkolinesteraze i butirilkolinesteraze s (R)- i (S)-enantiomerima kinuklidin-3-ola i kinuklidin-3-il-acetata te njihovih N-metilnih i N-benzilnih derivata, ne pokazuje stereoselektivnost tih enzima. Kao najbolji supstrat za oba enzima pokazao se (R)-N-metilkinuklidinijev acetat, s kcat = 1,5 x 106 min–1 za acetilkolinesterazu, odnosno kcat = 5,5 x 104 min–1 za butirilkolinesterazu. (R)- i (S)-N-benzilkinuklidinijevi derivati bili su najjači inhibitori za te enzime

Development of a two zone turbulence model and its application to the cycle-simulation

The development of a two zone k-ε turbulence model for the cycle-simulation software is presented. The in-cylinder turbulent flow field of internal combustion engines plays the most important role in the combustion process. Turbulence has a strong influence on the combustion process because the convective deformation of the flame front as well as the additional transfer of the momentum, heat and mass can occur. The development and use of numerical simulation models are prompted by the high experimental costs, lack of measurement equipment and increase in computer power. In the cycle-simulation codes, multi zone models are often used for rapid and robust evaluation of key engine parameters. The extension of the single zone turbulence model to the two zone model is presented and described. Turbulence analysis was focused only on the high pressure cycle according to the assumption of the homogeneous and isotropic turbulent flow field. Specific modifications of differential equation derivatives were made in both cases (single and two zone). Validation was performed on two engine geometries for different engine speeds and loads. Results of the cyclesimulation model for the turbulent kinetic energy and the combustion progress variable are compared with the results of 3D-CFD simulations. Very good agreement between the turbulent kinetic energy during the high pressure cycle and the combustion progress variable was obtained. The two zone k-ε turbulence model showed a further progress in terms of prediction of the combustion process by using only the turbulent quantities of the unburned zone

The development of regulations on approved harmful substances emissions from ic engines

U radu je opisan razvoj propisa o dopuštenim emisijama štetnih tvari iz motora s unutarnjim izgaranjem u Europi u razdoblju od 1970. godine do danas, s osvrtom na njihov razvoj u budućnosti. Osim na zakonski ograničene emisije štetnih tvari, dan je osvrt i na zahtjeve na gorivo potrebne za ispunjavanje propisa Euro 5 i 6 kao i na emisiju CO2, plina koji nije zakonski ograničen, ali je staklenički plin na kojeg se odnosi sporazum iz Kyota. Znatan napredak u smanjenju emisija štetnih tvari postignut je kontinuiranim poboljšavanjem tehnika pročišćavanja ispušnih plinova i uporabom sve kvalitetnijih goriva. Pritom treba naglasiti da se kvalitete goriva koje zahtijeva Svjetska povelja o gorivu Worldwide Fuel Charter - WWFC, koja predstavlja želje proizvođača motora, razlikuju od kvalitete goriva koju zahtijevaju propisi EU. Razvoj budućih propisa o emisiji i zahtjeva za kvalitetom goriva predstavlja isprepletene želje i mogućnosti proizvođača motora i vozila, proizvođača goriva, politike i zakonodavstva te pritiska „zelenih“. Posebnu težinu za donositelje zakonskih propisa u EU ima činjenica da je EU ovisna o uvozu goriva i svojevrsni je lider na području primjene alternativnih goriva i donošenja novih strožih propisa vezanih za emisije štetnih tvari.The paper describes the development of regulations on approved harmful substances emissions from internal combustion engines in Europe from the year 1970 till today, and it also emphasizes their development in the future. Apart from legally restricted use of harmful substances emissions, it also discusses the requirements for fuels which need to be met according to Euro 5 and 6, as well as the CO2 emission, which is not restricted by the law but it is the greenhouse gas covered by the Kyoto Protocol. A considerable progress has been made in reducing the harmful substances emissions by the constant improvement of cleaning techniques of gas emissions and by the use of more quality fuels. Here we need to emphasize that the quality of fuels required by the Worldwide Fuel Charter – WWFC, which represents the wishes of engine manufacturers, differs from the quality of fuels required by the EU regulations. The development of the future regulations on the emissions and the requirements on the quality of fuels combines the desires and possibilities of engine and vehicle manufacturers, fuel manufacturers, politics, legislation and the pressure of the green activists. The fact that the EU depends on the fuel import and stands out as the leader in the field of alternative fuel use and bringing new, more stringent regulations on harmful substances emissions has a great impact on the body behind the new regulations in the EU

CLINICAL RECOMMENDATIONS FOR DIAGNOSIS, TREATMENT AND MONITORING OF PATIENTS WITH INVASIVE BREAST CANCER

Rak dojke najčešća je maligna bolest u žena. Razvoj preventivnih mjera i dijagnostike i svih oblika liječenja (kirurgije, radioterapije, kemoterapije, hormonske i ciljane biološke terapije) doveo je do produljenja preživljenja i poboljšanja kvalitete života bolesnica. S ciljem optimalizacije i standardizacije liječenja, a slijedeći smjernice medicine temeljene na dokazima, donosimo smjernice za dijagnostiku, liječenje i praćenje bolesnica s rakom dojke koje su rezultat rada multidisciplinarnog tima stručnjaka.Breast cancer is the most common malignancy in women. Preventive measures, early diagnosis and development of all treatment modalities (surgery, radiotherapy, chemotherapy, hormonal and targeted biologic therapy) led to improvement in survival and quality of life of the patient. In order to standardize and optimize the approach, following good clinical practice standards, we bring consensus guidelines for diagnosis, treatment and monitoring of breast cancer patients as a result of consensus of a multidisciplinary team of experts for breast cancer

CLINICAL RECOMMENDATIONS FOR DIAGNOSIS, TREATMENT AND MONITORING OF PATIENTS WITH INVASIVE BREAST CANCER

Rak dojke najčešća je maligna bolest u žena. Razvoj preventivnih mjera i dijagnostike i svih oblika liječenja (kirurgije, radioterapije, kemoterapije, hormonske i ciljane biološke terapije) doveo je do produljenja preživljenja i poboljšanja kvalitete života bolesnica. S ciljem optimalizacije i standardizacije liječenja, a slijedeći smjernice medicine temeljene na dokazima, donosimo smjernice za dijagnostiku, liječenje i praćenje bolesnica s rakom dojke koje su rezultat rada multidisciplinarnog tima stručnjaka.Breast cancer is the most common malignancy in women. Preventive measures, early diagnosis and development of all treatment modalities (surgery, radiotherapy, chemotherapy, hormonal and targeted biologic therapy) led to improvement in survival and quality of life of the patient. In order to standardize and optimize the approach, following good clinical practice standards, we bring consensus guidelines for diagnosis, treatment and monitoring of breast cancer patients as a result of consensus of a multidisciplinary team of experts for breast cancer