1- EFFECT OF VACCUUM LEVEL, PULSATION RATIO, CLAW SIZE AND USING DUOVAC UNIT ON PERFORMANCE OF MACHINE MILKING OF FRIESIAN COWS The main objectives

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1 1- EFFECT OF VACCUUM LEVEL, PULSATION RATIO, CLAW SIZE AND USING DUOVAC UNIT ON PERFORMANCE OF MACHINE MILKING OF FRIESIAN COWS The main objectives of this study were, to investigate the influence of different vacuum levels (VL), pulsation ratio (PR), claw size (CS) and connection of Duovac unit on characteristics of milking machine, in order to provide preliminary information for future trials on milk flow rate and milking time of Friesian cows. The present study was carried out at Sakha Animal Production Research Station, Kafr El-Sheikh Governorate. Results revealed that machine milking yield (MMY) increased (P<0.05) from 8.7 kg at VL of 48 kpa to 9.0 and 9.05 kg at VL of 50 and 52 kpa, respectively. Total milk yield (TMY) increased (P<0.05) as the VL increased from 48 (8.9 kg) up to 52 Kpa (9.8 kg). Stimulation time (ST) was shorter (P<0.05) at 50 Kpa than at 52 Kpa (10.4 vs sec). Machine milking time (MMT) decreased (P<0.05) from 4.4 to 3.9 min by increasing VL from 48 to 50 kpa and to 3.5 min at 52 kpa. Stripping milk yield (SMT) only increased (P<0.05) from 0.6 min at 50 kpa to 0.9 min at 52 kpa. Total milking time (TMT) decreased (P< 0.05) from 4.9 min at 48 kpa to 4.6 and 4.4 min at 50 and 52 kpa, respectively. Milk flow rate (MFR) increased (P<0.05) from 2.0 to 2.3 kg/min at 50 kpa and to 2.8 kg/min at 52 kpa. Stripping milk yield (SMY) relative to TMY was higher (2.7%, P<0.05) for 48 Kpa than 50 and 52 Kpa (2.3 and 2.4%). Values of MMY decreased (P<0.05) only by changing PR from 65:35 up to 70:30 (8.7 vs. 9.2 kg). SMY decreased (P<0.05) by 33% only with changing PR from 60:40 to 65:35. TMY decreased (P<0.05) from 9.7 to 9.4 kg by changing PR from 60:40 to 65:35. However, changing PR from 65:35 to 70:30 reduced (P<0.05) TMY from 9.4 to 8.9 kg. ST decreased (P<0.05) from 11.3 to 10.5 sec only by changing pulsation ratio from 60:40 to 65:35. TMT was longer (1.9 vs. 4.6 min, P<0.05) by changing PR from 60:40 to 65:35 and from 65:35 to 70:30 (4.6 vs. 4.5 min, P<0.05). SMT decrease (P<0.05) from 0.70 to 0.68 sec only by changing PR from 60:40 up to 70:30. MMT decreased (P<0.05) by changing PR from 60:40 to 65:35 or to 70:30, being 4.2, 3.9 and 3.8 min, respectively. MFR increased (P<0.05) from 2.3 to 2.4 kg/min only by changing PR from 60:40 to 65:35. Percentage of SMY relative to TMY decreased (P<0.05) from 2.7% at 60:40 to 2.4% to 2.4% at 65:35 and changing PR to 70:30 decreased (P<0.05) percentage of SMY to TMY to 2.3%. SMY, ST, TMT, SMT, MMT and SMY relative to TMY were higher (P<0.05) with claw size of 150 than 350 cm3. However, TMY and MMY were higher (P<0.05) with claw size of 350 than 150 cm3. Increasing claw size from 150 to 350 increased (P<0.05) MFR from 2.2 to 23.5 kg/min, increased (P<0.05) MMY from 8.9 to 9.3 kg and decreased TMT, whereas SMY was the same in both cases of claw size. Using Duovac unit resulted in increase (P<0.05) in MMY from 9.0 to 9.2 kg and in TMY from 9.3 to 9.4 kg and decrease (P<0.05) in ST and MMT leading to reduction (P<0.05) in TMT from 4.9 to 4.5 min and increase (P<0.05) in MFR from 2.3 to 2.5 kg/min as compared to without using. Values of SMY decreased (P<0.05) from 0.3 to 0.2 kg and TMY increased (P<0.05) and SMY relative to TMY decreased (P<0.05) from 2.8 to 2.1%. Keywords: Milking machine, vacuum, pulsation, claw, Duovac unit, milk flow rate. 2- THERMAL PROPERTIES OF SOME OIL PRODUCING CROPS

2 The thermal properties such as specific heat, thermal conductivity, thermal diffusivity and volumetric heat transfer coefficient for three different oil producing crops (sunflower variety Giza 102, soybean variety Giza 111 and canola variety Serow 55) were determined at five different levels of seeds moisture content and temperature. The results show that, the specific heat was found to be both seeds moisture content and temperature dependent. Its value increased linearly with the increasing of both seeds moisture content and temperature for all studied crops. Also, the seeds moisture content had higher effect on seeds specific heat than that of seeds temperature. Thermal conductivity and thermal diffusivity were increased with the increase of seeds moisture content while, thermal diffusivity decreased linearly with the increasing of seeds temperature for all studied crops. Also, the volumetric heat transfer coefficient was increased linearly as the air flow rate and air temperature increased. Mathematical relationships were also developed for the different studied crops to relate the change in seeds moisture content, temperature and mass air flow rate with the obtained values of all thermal properties. 3- THE RELIABLE SELECTION OF A RICE MILLING MACHINERY SYSTEM FOR EGYPTIAN CONDITIONS The milling performances of four rice milling machinery systems of different whitener units have been tested and compared. These systems include the One-Pass milling system (M1); Two-Pass milling system (M2); Three-Pass milling system (M3), and the locally (Engelberg) milling system (M4). The milling tests have been deduced against, three different rice varieties and at three grain moisture content levels. The milling processes of these systems have been evaluated in terms of the milled grain quality, the mill energy consumption, and the milling machinery costs. The gained results indicated that the three-pass system (M3) produced the highest extra grade rice, and the lowest broken ratio (2 %). In addition, the minimum machinery cost (11.8 LE/ton), and the lowest specific energy consumption (28.06 kwh/ton) are accomplished the two-pass system (M2). Finally, the Engelbarg system (M4) exhibits the highest specific energy consumption ( kwh/ton), the highest broken grain ratio (26.72 %), and the lowest rice quality grade (No5). 4- AERO-DYNAMICS AND MECHANICAL PROPERTIES OF SOME OIL PRODUCING CROPS Aero-dynamic and mechanical properties such as terminal velocity, Reynoldâ s No., drag coefficient, coefficient of friction, repose angle and seeds hardness for three different oil producing crops (sunflower, soybean and canola) were determined at five different levels of seeds moisture content; while, shear force and shear stress of soybean hulls and cotyledons were also determined at the proper moisture content for oil extraction. The obtained results show that, for aerodynamic properties, both of terminal velocity and Reynoldâ s Number of all studied crops increased linearly with the increase of seeds moisture content. While, drag coefficient decreased with the increase of terminal velocity. However, coefficient of friction was varied with seeds moisture content and type of friction surface. Also, it was increased with the increase of seeds moisture

3 content. Meanwhile, stainless steel surface recorded the lowest values of friction coefficient whereas the rubber surface recorded the highest values. Also, the angle of repose increased with the increasing of moisture content. While, seed hardness decreased with the increase of moisture content. However, both of shear force and shear stress of soybean hulls and cotyledons were higher in the longitudinal direction as compared with the lateral direction. Mathematical relationships were also developed for the different studied crops to relate the change in seeds moisture content with the obtained values of all aero-dynamics and mechanical properties. 5- EFFECT OF GREENHOUSE GLAZING MATERIALS ON EVAPORATIVE COOLING SYSTEM EFFECTIVENESS FOR PRODUCTION OF TOMATOES UNDER HOT- HUMID SUMMER CONDITIONS To insure optimal fruit yields of greenhouse tomatoes crop in Mansoura, Egypt, when greenhouse day temperatures can be in excess of 50?C, planting was dictated to be in late April to early September. To reduce daylight temperatures during summer months of 2007, fan-pad cooling system was examined under different glazing materials in a 32 m2 greenhouses: 1) corrugated fiberglass reinforced plastic (FRP), and, 2) double layer polyethylene sheets (PE). Tomato plants (Ebesia verity) were transplanted on 21 April, 2007 into 60 plastic pots in each greenhouse with plant density of 2.5.ا m² At transplanting the cooling system of 2.4 x 1.0 m in the west wall and one extracting fan in the east wall was automatically activated when the two greenhouses air temperatures reached to 28?C. Air temperature, relative humidity, wind speed, and total solar radiation entering the greenhouse were measured and recorded on a data-logger to analyses their correlation with tomatoes crop yield response. A mathematical model was developed to simulate microclimate on and around leaf surface for greenhouse tomatoes. The obtained results revealed that the air temperature and relative humidity inside the two greenhouses of 28.5?C and 29.8?C, 53.3% and 55.7%, respectively were maintained during summer months at and around noon. Furthermore, the obtained data revealed generally high uniformity of the microclimatic conditions within the greenhouse, in the lengthwise (eastwest) and vertical directions. In contrast to that, there was a little variation across the width of the greenhouse (north-south) which arose as a result of solar radiation intensity and wind actions. It can be concluded that, due to the optimal level of microclimatic conditions inside the two greenhouses with an evaporative cooling system, they produced fresh yield of and kg/m2, respectively, consequently, greenhouse 1 increased the fresh yield by 19,58% as compared with the greenhouse 2. It must also be concluded that in order to obtain completely uniform microclimatic conditions throughout the volume of the greenhouse, it is desirable to install shading black net on the roof of greenhouse. 6- UTILISATION OF SOLAR TUNNEL GREENHOUSE AS A SOLAR DRIER FOR DRYING SEEDLES GRAPES: I: THERMAL PERFORMANCE ANALYSIS OF SOLAR DRIER In this research work an attempt has been made to analyse the thermal performance of solar tunnel greenhouse which can be utilised as a solar drier for seedless grapes. Three

4 identical solar tunnel greenhouse driers (STGD) were used under the climatic conditions of El-Mansoura city, Egypt (latitude and longitude angles of Nا and 31.37, Eا respectively), during August The thermal performance analysis of the solar driers (active or dynamic drier) based on the energy balance equations was evaluated. The three active solar driers were operated under three different mass flow rates of 0.122, 0.183, and kg/s. The obtained results revealed that, the daily average solar energy available outside the solar driers was kwh of which kwh was available inside the drier with an average effective transmittance of 75.16%. The daily average solar energy available inside the three solar tunnel greenhouse driers during the experimental period was kwh of which 6.993, 7.699, and kwh, respectively, converted into useful heat gain. These solar energy available inside the three solar driers resulting in increase the inside air temperatures above the outside ( C ا 31.6 ) by 21.9, 12.5, and, C ا 9.4 and reduce the air relative humidity under the outside (40.6%) by 9.0%, 3.1%, and 5.1%, respectively. The daily average overall thermal efficiencies of the three solar tunnel greenhouse driers during the experimental period were 55.62%, 61.24%, and 53.19%, consequently, 44.38%, 38.76%, and 46.81% of the solar energy available inside the solar driers was lost, respectively. The predicted heat energy for the three solar driers was validated well with that measured during the experimental period by 0.995, 0.991, and 0.998, respectively, which gave an excellent agreement. 7- DEVELOPING A SOLAR HEATING SYSTEM FOR HEATING SWEET COLOUR PEPPER GREENHOUSE The objective of the present study was to evaluate the effect of solar heating system on the microclimatic conditions of sweet colour pepper greenhouse during winter season of The use of solar energy system for greenhouse heating in winter and cold days helps to save fossil fuels and conserve green farm environment on the one hand, and on the other, enhances the quality of greenhouse products, reduces production costs and limits the release of greenhouse gases. Temperatures of inside and outside air, solar radiation flux incident, and air relative humidity of inside and outside for the last five years at nighttimes have been collected and used to calculate the total heat losses from the greenhouse. Using this data the solar collector area and collector configuration were calculated so that the optimal surface area of solar collectors was found to be 4 m2 that adequate to heat the sweet colour pepper crop greenhouse. The thermal performance analysis was experimentally determined, by measuring the temperature increase at various water inlet temperatures and intensity of solar radiation, under clear sky conditions. A complete solar heating system (two solar collectors and storage tank) was utilised for heating 300 litres of water. The daily average overall thermal efficiencies of the solar collector and the storage system during the experimental period were 71.3% and 91.3%, respectively. Over a 181 days season the solar heating system collected 3813 kwh of energy or 70.5% of the total heat energy required to heat the greenhouse ( kwh). This percentage could be increased by reducing heat losses from the greenhouse. Due to the microclimatic conditions of the greenhouse were at or around the desired level, the sweet colour pepper had have optimal vegetative growth rate, stem length, number of fruits being seated, and fresh yield. The total costs per square meter of greenhouse were L.E The fresh yield of sweet colour pepper was kg/m2, which sold by L.E. 80.1, consequently, the estimated return on capital was 42.8% per

5 annum. 8- A COMPARTIVE STUDY ON TWO DIFFERENT EVAPORATIVE COOLING SYSTEMS FOR PRODUCTING CUCUMBER CROP UNDER HOT-HUMID SUMMER CONDITIONS The influence of greenhouse evaporative cooling systems (based on misting, and fan pads cooling systems) on the microclimatic conditions of greenhouse cucumber was studied and investigated in two fiberglass greenhouses combined with roof shading black net screen situated on the roof of the Agricultural Engineering Department, University of Mansoura. Measurements were executed during several days (122 days) in the hot summer of 2009; (G1) with a mist system operating 15 sec every 15 min., (G2) with a pad-fan system. In order to compare between the cooling systems, air temperatures and relative humidity inside and outside the greenhouses were measured and recorded. Experimental data revealed that the pad-fan cooling system was able to keep the air temperature within the greenhouse at rather low levels. The internal air temperature stayed C ا 8.0 below outside, even during hot afternoons (Tao >.( C ا 35 Whereas, the evaporative cooling using mist system kept the greenhouse air temperature above the set point temperature by an average of. C ا 4.9 Therefore, the internal air temperature stayed C ا 4.2 below outside. Due to the short length of the greenhouse (8 m), small temperature gradients ( C ا 2.9 ) were observed from wet pads to extracting fan. The cooling system using fan-pad system inside the greenhouse (G2) was on the average more efficient than the misting system inside the greenhouse (G1) by 22.5% due to the cooling operation period for the greenhouse (2) was longer than that for the greenhouse (1), accordingly, the water temperature of cooling system (2) was lower than that in misting system (G1). The total fresh yield of cucumber crop per square meter for greenhouse (G1) and greenhouse (G2) was and kg/m2, respectively. Therefore, the greenhouse (G2) produced kg /m2 (44.31%) more than the greenhouse (G1). 9- COMPOSTING OF DECIDUOUS TREES LEAVES AND CATTLE DUNG: EFFECT OF TURNING OPERATION IN PROCESS PERFORMANCE The aim of this study was to evaluate the feasibility of composting fallen leaves and cattle dung and the effect of turning frequency on final compost quality. A bioreactor vessel was designed, manufactured, and situated on the roof of the Agricultural Engineering Department, Faculty of Agriculture, Mansoura University for rapid composting of admixture leaves and cattle dung from November 2008 until June This bioreactor vessel is conical in shape (right frustum of cone) and made of double layer of stainless steel sheet 1 mm thick with a net volume of m3. A series of experiments were executed to investigate some engineering factors affecting performance of composting process such as; size of fallen leaves and stirring or turning frequency. Laboratory tests were also carried out to assess and evaluate some physical and chemical properties of raw composting materials, fresh compost, and final compost after curing process. Two different particle sizes of fallen leaves (shredded leaves of mm and complete leaves) and one aeration rate (0.007 m3/min) were functioned. Two different levels of manual stirring (without and with stirring once every six days) were used. The obtained results revealed that, to maximize the microbial activity and speed up the

6 composting process of admixture materials, they would be aerated by a rate of m3/min, stirred once every six days, and shredded fallen leaves to a smaller particles size. The obtained results also showed that, the final compost contented Nitrogen (N), Phosphorus (P), and potassium (K) of 3.181%, 0.318%, and 3.790%, respectively. They also revealed that, there were no weed seeds found in all treatment samples of fresh and final composts. Rising up the temperature of admixture materials and persisting from the first day until the end of fifth day during the thermophilic phase caused in destructed of pathogens and other organisms.