in this research in order to estimate genetic parameters for milk yield at different milking times for holstein cows of razavi khorasan, a total of 180,462 monthly test day records belonging to first lactation cows calved from 2000 to 2009 were utilized. the records were analysed by a random regression test day model. in the model, the fixed effects of contemporary group of geographical locatio...

introduction water super absorbents are water absorbing natural or synthetic polymers (they may contain over 99% water). they have been defined as polymeric materials which exhibit the ability of swelling in water and retaining a significant fraction (> 20%) of water within their structure, without dissolving in water content. the applications of hydrogels are grown extensively. these materials...

for determining sugar beet water requirements, this work was conducted at the  agricultural research station of torog in mashhad for 3 years. crop water requirement was measured by a drainage type lysimeter with dimension of 2*2*1 m. in order to reduce side effects, an area about 1600 m2 around the lysimeter (as a guard) was cultivated with sugar beet. soil water content was measured by tensiom...

This study aims to derive the optimal solution for well locations based on the allowable withdrawal. To demonstrate the proposed technique, a numerical model of a typical well field at the Qinbei Power Plant was constructed and 20 possible drawdown scenarios were simulated for each of three different arrangements of pumping wells. The concept of the Unit Increased Drawdown Value (UIDV) was used...

Finite-time thermodynamic models for an Otto cycle, an Atkinson cycle, an over-expansion Miller cycle (M1), an LIVC Miller cycle through late intake valve closure (M2) and an LIVC Miller cycle with constant compression ratio (M3) have been established. The models for the two LIVC Miller cycles are first developed; and the heat-transfer and friction losses are considered with the effects of real...

Sampling of triethylamine in the cold-box unit in an auto-manufacturing company in Iran has indicated the average concentration of 430 mg/m3 in the emission duct. In this study a biotrickling filter was used for treatment of triethylamine in air stream. Triethylamine removal efficiency (K/L) pattern was evaluated by changing volumetric loading (L), superficial gas velocity (Uo), empty bed gas r...

terms and conditions of current drinking water quality standards, including reducing the maximum arsenic concentration from 50 μgl-1 to 10 μgl-1 and predicted stricter standards in future, reveals the necessity for development of new technologies. this study aimed to prepare and evaluate a new nanocomposite membrane using graphene oxide (go) thin layer to remove arsenic (v) from water. to fabri...

The development of aeroponic cultivation technology has led to more efficient use of water and plant nutrients for producing high quality agricultural commodities. In this research, cucumbers were grown in columnar aeroponic systems for nine weeks and the effect of spraying rate and spraying duration on the cucumber average yield and water usage efficiency were investigated. The experiments wer...

for determination of irrigated sugar beet crop evaporation (etc) and water consumption a field experiment was conducted for three years (1991 to 1993)  in kabotar-abad agricultural experiment station. the climate was semi-arid according to gossen method with mean annual precipitation of 90 to 110 mm. the soil was esfahan series with a silty clay loam texture. the crop evapotranspiration was mea...