11 research outputs found
Sensor for Injection Rate Measurements
A vast majority of the medium and high speed Diesel engines are equipped withmulti-hole injection nozzles nowadays. Inaccuracies in workmanship and changinghydraulic conditions in the nozzles result in differences in injection rates between individualinjection nozzle holes. The new deformational measuring method described in the paperallows injection rate measurement in each injection nozzle hole. The differences in injectionrates lead to uneven thermal loads of Diesel engine combustion chambers. All today knownmeasuring method, such as Bosch and Zeuch give accurate results of the injection rate indiesel single-hole nozzles. With multihole nozzles they tell us nothing about possibledifferences in injection rates between individual holes of the nozzle. At deformationalmeasuring method, the criterion of the injected fuel is expressed by the deformation ofmembrane occurring due to the collision of the pressure wave against the membrane. Thepressure wave is generated by the injection of the fuel into the measuring space. For eachhole of the nozzle the measuring device must have a measuring space of its own into whichfuel is injected as well as its measuring membrane and its own fuel outlet. Duringmeasurements procedure the measuring space must be filled with fuel to maintain anoverpressure of 5 kPa. Fuel escaping from the measuring device is conducted into thegraduated cylinders for measuring the volumetric flow through each hole of the nozzle.Themembrane deformation is assessed by strain gauges. They are glued to the membrane andforming the full Wheatstone’s bridge. We devoted special attention to the membrane shapeand temperature compensation of the strain gauges
Calculation of thermophysical and thermochemical
Abstract. A mathematical model is presented for computing the chemical and thermophysical properties in the process of combustion of natural gas. To identify the parameters of state of combustion products, their composition has to be known, which may be determined from chemical equilibrium. The computation is performed with the use of chemical potentials and statistical thermodynamics, featuring all important molecular contributions (translation, rotation, vibration, and intermolecular potential energy). A thermal equation of state with two virial terms is used. The real gas mixture is treated as consisting of four components: carbon dioxide, nitrogen, carbon monoxide, and water. Virial coefficients are dependent on temperature and mole fractions of the real components. Mixed terms are taken into account. The caloric equation of state is based on statistical thermodynamics for an ideal gas. Corrections are made in accordance with the second law of thermodynamics and the thermal equation of state. As the whole computation is based on matrix algebra, increasing the number of components presents no problems. We tested our model in the high-pressure region (100 bar) and the low-pressure region (1 bar), in the temperature range 500 ^ 6000 K. Our model is compared with other analytical models presented in the literature and shows relatively good agreement. At the same time we tested the influenc
Efikasnost mandipropamida za suzbijanje prouzrokovača plamenjače krompira u poljskim uslovima
The efficacy of mandipropamid (Revus 250 SC) in controlling Phytophthora infestans
in potato was evaluated in field trials. The efficacies of Revus 250 SC in comparison with
standard fungicides Quadris (azoxystrobin) were tested in several localities in Serbia
(Kasarske Livade, Valjevska Kamenica and Opovo) in 2007 and 2008. Both of the tested fungicides
exhibited high efficacy in controlling potato late blight. The differencies in the efficacy
of Revus 250 SC (96.3- 99.2%) and Quadris (94.1-95.5%) were insignificant. Our experiments
showed that the investigated fungicide was highly effective against P. infestans even
under high disease pressure.Ispitivana je efikasnost mandipropamida (Revus 250 SC) za suzbijanje Phytophthora infestans
u usevu krompira u poljskim uslovima. Efikasnost preparata Revus 250 SC ispitivana je na nekoliko
lokaliteta u Srbiji (Kasarske Livade, Valjevska Kamenica i Opovo) tokom 2007. i 2008. godine.
Kao standard poslužio je Quadris (azoksistrobin). Oba ispitivana fungicida su ispoljila visoku
efikasnost u suzbijanju prouzrokovača plamenjače krompira. Između efikasnosti Revus 250 SC
(96.3- 99.2%) i Quadris (94.1-95.5%) nije utvrđena statistički značajna razlika. Naši ogledi su pokazali
da je ispitivani fungicid visokoefikasan u suzbijanju P. Infestans, čak i u uslovima jake zaraze
Mogućnost zaštite šampinjona od paučinaste plesni sterilisanjem pokrivke ekološkim sredstvima
The soil-borne pathogen Cladobotryum dendroides causes cobweb disease of button
mushroom (Agaricus bisporus) and its significant yield losses. Casing soil disinfection by toxic
formaldehyde is a widespread practice. The aim of this study was to investigate the potential of
two environmentally friendly substances, colloidal silver and peracetic acid, against C. dendroides.
Their biological efficacy (impact on mushroom yield), effectiveness (disease control) and type
of interactions between them and the fungicide prochloraz-manganese were evaluated.
Black peat/lime casing soil was applied to a colonized substrate with the white button
mushroom strain 737, then inoculated with C. dendroides and treated with the fungicide
prochloraz-manganse and two environmentally friendly disinfectants based on peracetic
acid and colloidal silver. The effects of fungicides on mushroom productivity were evaluated
as biological efficacy and calculated as a ratio of fresh weight of total mushroom yield to
the weight of dry substrate. Fungicide effectiveness and synergy factor were calculated by
Abbott’s (1925) formula. Tests for synergism between prochloraz-manganese and both other
substances were performed using Limpel’s formula.
The highest biolgical efficacy, exceeding 92.00, was achieved in treatments with prochlorazmanganese,
applied alone or in combination with both other disinfectants. The highest
effectiveness of 93.33% was attained in treatments with peracetic acid combined with
prochloraz-manganese. Trials against cobweb disease revealed a synergistic reaction between
the fungicide and peracetic acid and antagonistic between the fungicide and colloidal silver.
Peracetic acid provided better disease control, compared to colloidal silver applied alone or in
combination with the fungicide. Based on these findings, peracetic acid should be recomended
as an environmentally friendly casing soil disinfectant against cobweb disease of A. bisporus.Zemljišna mikromiceta Cladobotryum dendroides izaziva paučinastu plesan šampinjona
(Agaricus bisporus) i nanosi značajne štete u proizvodnji. Uobičajen način dezinfekcije pokrivke
za gajenje šampinjona je tretiranje formaldehidom koji ima toksična svojstva. Cilj ovog rada
je ispitivanje mogućnosti primene dva ekološka dezinfekciona sredstva na bazi koloidnog
srebra i persirćetne kiseline u suzbijanju C. dendroides. Određena je njihova efikasnost, uticaj
na prinos šampinjona i međusobna reakcija sa fungicidom prohloraz-Mn.
Pokrivka od crnog treseta i kreča je stavljena na supstrat zasejan micelijom šampinjona
soj 737, inokulisana patogenom C. dendroides i tretirana fungicidom prohloraz-Mn i ekološkim
dezinficijensima na bazi persirćetne kiseline i koloidnog srebra. Uticaj antifungalnih supstanci
na prinos (biološka efikasnost) je određen kroz srazmeru mase ukupnog prinosa šampinjona
i mase suvog supstrata. Efikasnost fungicida u suzbijanju patogena i sinergistički faktor su
izračunati primenom Abotove formule. Sinergizam između prohloraz-Mn i oba dezinficijensa
je određen pomoću Limpelove formule.
Najveća biološka efikasnost je utvrđena u tretmanima sa prohloraz-Mn, preko 92,00,
primenjenim pojedinačno ili u kombinaciji sa oba dezinficijensa. Najveća efikasnost u
suzbijanju patogena, 93.33%, postignuta je u kombinovanoj primeni fungicida sa persirćetnom
kiselinom. Ustanovljen je sinergizam između fungicida i persirćetne kiseline i antagonizam
u kombinovanoj primeni fungicida i koloidnog srebra.
Primenom persirćetne kiseline omogućena je veća efikasnost u poređenju sa koloidnim
srebrom u suzbijanju prouzrokovača paučinaste plesni, bilo da je primenjena pojedinačno
ili u kombinaciji sa fungicidom. Na osnovu ovih ispitivanja, može se preporučiti primena
persirćetne kiseline kao ekološkog dezinficijensa pokrivke za gajenje šampinjona i zaštitu
od paučinaste plesni