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991.
Alfalfa was harvested in large round bales or small square bales and storage and feeding losses were determined for different storage methods. Large bales were stored 1) in a barn; 2) outside in single rows and uncovered; 3) outside in two-high stacks and covered; and 4) outside in three-high stacks and covered. These bales were fed to dairy heifers with small square bales for comparison. Dry matter storage losses were 2% for large bales stored inside, 6% for large bales stored outside covered, and 15% for large bales stored outside uncovered. Feeding losses of large bales were 12% for stored inside, 25% for stored outside uncovered, and 13 to 15% for stored outside covered. Total losses for large round bales were 40% (stored outside uncovered), 20% (stored outside covered) and 15% (stored inside). Intake and gains were greatest for small bales (2.35 kg/100 kg body weight and .77 kg/d, respectively) and least for large bales (2.11 kg/100 kg body weight and .54 kg/d) stored outside uncovered.Rain penetrated 10 to 25 cm into uncovered bales stored outside. The resulting weathered hay, about 40% of the original bale dry weight, deteriorated. Heifers rummaged through this unpalatable material, and large feeding losses resulted. Storage and feeding losses of large round bales stored outside are economically important enough to warrant protection of bales.  相似文献   
992.
The effects, during formation, of current density, charge capacity, and concentration and temperature of H2SO4 electrolyte on the capacity of tubular electrodes in lead/acid batteries have been studied. Electrode capacity was found to be maximum at a H2SO4 concentration of 1.05 sp. gr., a charge amount of 250% theoretical capacity, a current density of 0.44 A dm?2, and an electrolyte temperature of 40 °C. A study of the soaking process for tubular electrodes showed the electrode capacity to be maximum when the acid absorption was about 170 mg of H2SO4 per g of oxide. Finally, the discharge overpotential of tubular electrodes was analyzed by a galvanostatic transient method.  相似文献   
993.
The microstructure and microtexture in adiabatic shear bands (ASBs) on the titanium side in the titanium/mild steel explosive cladding interface are investigated by means of optical microscopy, scanning electron microscopy/electron backscattered diffraction (SEM/EBSD), and transmission electron microscopy (TEM). Highly elongated subgrains and fine equiaxed grains with low dislocation density are observed in the ASBs. Microtextures (25 deg, 75 deg, 0 deg), (70 deg, 45 deg, 0 deg), and (0 deg, 15 deg, 30 deg) formed within the ASBs suggest the occurrence of the recrystallization. The grain boundaries within ASBs are geometrically necessary boundaries (GNBs) with high angles. Finite element computations are performed to obtain the effective strain and temperature distributions within the ASBs under the measured boundary conditions. The rotation dynamic recrystallization (RDR) mechanism is employed to describe the kinetics of the nanograins’ formation and the recrystallized process within ASBs. During the deformation time (about 5 to 10 μs), the following processes take place: dislocations accumulate to form elongated cell structures, cell structures break up to form subgrains, and subgrains rotate and finally form recrystallized grains. The small grains within ASBs are formed during the deformation and do not undergo significant growth by grain boundary migration after deformation.  相似文献   
994.
A compact fiber-optic magnetometer constructed using a short piece of amorphous metal wire (5-cm long×100-μm diameter) as the magnetostrictive transducer is discussed. The inherently large ratio of length to cross-sectional area results in a low demagnetization along the axial direction. A magnetostrictive constant of 5×10-5 /Oe2, which is 10-50 times larger than the reported values for transducers made from Metglas ribbons, was measured. Minimum detectable magnetic fields on the order of 10-5 Oe/Hz1/2 at 1 Hz were achieved using a 5-cm-long sensing fiber  相似文献   
995.
Recent reports in the literature indicate that incidents involving fires and explosions in the spray drying of milk products are increasing in number. Whilst milk powder is not highly explosible, the conditions for a dust explosion, apart from the ignition source are almost always present in certain areas of a spray dryer during its normal operation. Self-ignition of deposits is known to be possible at the high temperatures in a spray dryer. At best, this can cause product degradation and discolouration whilst at worst it can provide the source of ignition for an explosion. This paper is an attempt to draw together recent work on fire and explosion prevention and protection formilk powders.  相似文献   
996.
The effects of amounts of gelatinized starch and moisture in the final slurry or dough, cooking time, holding time, and holding temperature on physical properties of mungbean noodles were studied. Cooking loss, cutting stress, work to cut, and transparency of noodles were measured. Moisture content of the final slurry or dough, cooking time, and holding temperature were the most important factors that affected physical properties of mungbean noodles. Processing should be done at moisture contents not exceeding 55%, cooking times not longer than 40 set, and holding temperatures not lower than 3° using 5% of total starch as gelatinized starch and holding time of 36 hr.  相似文献   
997.
Swine carcass microflora were evaluated for selected foodborne pathogens after exposure to reconditioned water during scalding, dehairing, and polishing operations. Reused water had been reconditioned and chlorinated. Rodac plates applied to hams were used to assess carcass microflora. Water samples were enumerated using membrane filtration or spiral plating. Sampling was at mid-week throughout the year. Total aerobic plate counts on hams were unaffected by treating with potable or reconditioned waters. No differences were observed for staphylococci, enterics, fecal streptococci, Listeria monocytogenes, coliforms, and Aeromonas levels. A preevisceration potable water carcass wash reduced the bacterial load, regardless of initial treatment. Bacterial counts on carcasses paralleled those in water. Reuse is an alternative to potable water for initial slaughter operations without diminishing bacteriologic safety.  相似文献   
998.
A survey of aflatoxin B1 (AFLB1) levels in commonly used commercial shrimp finisher feeds in the Philippines showed a various range of values from not detected to 120 μg kg?1 using high-performance thin-layer chromatography. Six experimental diets were prepared to contain various levels of AFLB1 based on survey results to determine the effects of such contamination in pre-adult shrimp Penaeus monodon (17.5 ± 0.6 g). Results showed that shrimps fed diets containing AFLB1 greater than or equal to 73.8 μg kg?1 gave comparatively poor growth rate and higher susceptibility to shell diseases. No AFLB1 residues were detected in sampled whole shrimp tissues after 62 days of exposure to AFLB1 containing diets indicating a low potential for transmission of the toxin from edible shrimp tissues to consumers. Histopathological alterations in the hepatopancreas of shrimp chronically exposed to AFLB, were observed in all samples. The degree of alterations correlated with the level of AFLB1. Based on growth performance, pre-adult shrimps can tolerate AFLB1 levels of up to 52.3 μg kg?1 in the feeds although histopathological changes were already evident in the tissues of shrimps given diets with 26.5 μg kg?1 AFLB1.  相似文献   
999.
A new principle for a high speed BiCMOS differential track-and-hold circuit based on current mode processing is presented, and simulation results are given. The main characteristics are an acquisition time of 5.5 ns for 8 bit precision and a small-signal bandwidth of 1 GHz  相似文献   
1000.
Plaza  G. Mesa  F. Horno  M. 《Electronics letters》1994,30(17):1425-1427
Spectral domain analysis is adapted to analyse the conductor losses of a multiconductor system embedded in a multilayered medium using a quasi-TEM approach and assuming a strong skin effect. After adapting the incremental rule to a multiconductor system, the conductor losses are computed in terms of the derivative of the inductance matrix  相似文献   
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