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Miniature cyclone separators have important applications in the detection of bioaerosols in ambient air. Experiments have shown that miniature cyclones can be used to collect bioaerosol particles with high efficiencies and with an acceptable pressure drop in the separation unit. However, performance correlations based on large cyclones are not valid for small-scale cyclones. In this study, the effect of the scaling of the cyclone and four different geometric parameters—conical length, vortex-finder length, vortex-finder diameter and underflow diameter—on the performance of a cyclone separator is investigated. Based on the results of numerical computations, generalized performance correlations, relating the pressure coefficient and the total collection efficiency to dimensionless geometric and operational parameters are developed.

The design and operation of an experimental facility to generate nanocrystalline zinc by the expansion of zinc and argon vapor in a supersonic free jet are described. The grain size of the compacted nanocrystalline zinc was found to lie between 10 and 20 nm and could be controlled by the zinc mole fraction in the stream and the back pressure in the expansion section. Measurements of physical properties show that nanocrystalline zinc is 5 to 7 times harder than polycrystalline material and the hardness decreases with increasing grain size. Some results from strain rate sensitivity and positron annihilation experiments are also reported.

Models for random coalescence of freely rising bubbles are developed for both a binary and nonbinary process. The bubble size distribution predicted by the binary model is represented well by the geometric and exponential distributions for a large number of bubbles and coalescence events. The nonbinary model that assumes simultaneous coalescence of bubble clusters yields bubbles sizes that follow the Pareto distribution. The Pareto model compared well with five measured distributions while the exponential model showed essentially no correlation. This and prior experimental observations shows that bubble coalescence is not binary but rather occurs by formation of bubble clusters.

The metabolism of a single oral zinc-65 dose was studied in young dairy calves fed two concentrations of added A1 (0 and .20% A1) and two concentrations of added P (0 and .22% P) for 7 wk. The four treatments were 1) normal P-low A1, 2) low P-low A1, 3) normal P-high A1 and 4) low P-high A1. The basal diet (low P-low AL) contained, by analysis, .132% P, .74% Ca, .021% A1 and 59 ppm Zn. Zinc-65 absorption was greater (66.5 vs 63.2% of dose, P less than .10) with the low-P diet; added A1 reduced (P less than .05) 65Zn absorption. Calves fed low-P diets had higher (P less than .10) concentrations of 65Zn in liver, kidney, spleen, heart, small intestine and testicle than those fed normal-P diets. Zinc-65 was reduced (P less than .10) in pancreas, heart, testicle and muscle of calves fed high A1. Iron was increased in liver and kidney (P less than .10), Zn (P less than .10) and Mn (P less than .01) were increased in liver, but Fe in small intestine and Cu in muscle and tibia shaft were decreased (P less than .10) in calves fed the low-P diets compared to those fed adequate-P diets. High A1 reduced (P less than .10) Cu in small intestine and tibia shaft. The results suggest that zinc metabolism may be moderately affected in calves fed either low-P or high-A1 diets.

The metabolism of Mg was studied in young dairy calves fed two levels of added Al (0 and .20% Al) and two levels of added P (0 and .22% P) for 7 wk. The four treatments were 1) normal P - low Al, 2) low P - low Al, 3) normal P - high AI and 4) low P - high AI. The basal diet (low P - low Al) contained, by analysis, .132% P, .021% Al and .17% Mg. Added AI did not affect (P > .lo) serum Mg. An AI x P interaction on bone Mg was detected (P c .01). Magnesium was reduced in tibia shaft (.34 vs .44%) and in tibia joint (.43 vs .53%) in calves fed high Al in the presence of normal dietary P, but Mg was not reduced in the calves fed low-P diets. Apparent absorption of Mg was reduced by approximately five-fold (.I8 g/d vs -.84 gld, P c .Ol): urinary Mg excretion was reduced 31% (1.12 g/d vs .77 g/d, P < .Ol); and Mg retention declined 41% (-95 g/d vs -1.61 g/d, P e .01) in calves fed added Al. Compared with calves fed low-P diets, calves fed normal levels of P had a higher Mg concentration in tibia shaft (P < .01) and tibia joint (P < .05). The data indicate that supplemental AI may adversely affect Mg metabolism in calves. (Key Words: Dairy Cattle, Calves, Aluminum, Phosphorus, Magnesium, Metabolism.)

The Underground Storage Tank Integrated Demonstration (UST-ID) is evaluating several hydraulic dislodger concepts and retrieval technologies to develop specifications for system that can retrieve wastes from single-shell tanks. Each of the dislodgers will be evaluated sequentially to determine its ability to fracture and dislodge various waste simulants such as salt cake, sludge, and viscous liquid. The retrieval methods will be evaluated to determine their ability to convey this dislodged material from the tank. This report describes on-going research that commenced in FY93 to develop specifications for a scarifier dislodger coupled with a pneumatic conveyance retrieval system. The scarifier development is described in Section 3; pneumatic conveyance development is described in Section 4. Preliminary system specifications are listed in Section 5. FY94 plans are summarized in Section 6.

The metabolism of Zn and tissue mineral concentrations were studied after a single oral 65Zn dose in 10 6-wk-old Holstein calves injected subcutaneously daily with 0 (control) or 10 mg of sometribove (recombinant methionyl bST) for 6 wk. Zinc-65 absorption was not significantly affected by bST; its concentration in the semitendinosus muscle was reduced by 32% in the bST calves, but concentrations in liver, pancreas, spleen, kidney, heart, small intestine, testicle, and rib were not different from controls. Manganese content was reduced by 27% in liver, 60% in kidney, 99% in spleen, 92% in testicles, and 33% in rib. Iron content of pancreas, spleen, and testicle and Zn content of rib were increased in the bST calves. The data indicate that Zn metabolism was not affected adversely by bST. Manganese content of several tissues was significantly reduced in the bST calves; however, no clinical signs of an Mn deficiency were evident.

Ten intact male Holstein calves averaging 75kg of BW and 59 d of age were used to study the effects of daily injections of 0 (control) or 10mg of sometribove (recombinant methionyl bST) for 6 wk on performance, health, carcass composition, N metabolism, chemical blood characteristics, and hormone profiles. Average daily gain, feed intake, feed:gain ratio, and height at withers, hip, and hock were not influenced by bST. Carcasses from bST-treated calves contained 5% more protein and 36% less lipid than controls. Circulating concentrations of Ca, P, glucose, urea N, alkaline phosphatase, creatine phosphokinase, insulin-like growth factor-I and insulin were not affected by bST. Packed cell volume was decreased about 7% (29.9 vs. 32.4%) in the bST calves. Hormone injection did not adversely affect health of the calves as measured by body temperature and by pulse and respiration rates. The most profound effects of sometribove were a reduction in carcass lipid and an increase in body proteins. These effects may be of some practical importance when leanness of carcass is desirable.

Sixteen male intact Holstein calves averaging 72kg and 64 d of age were used to study the effects of high dietary Al on calf performance and P bioavailability. The main effects were two concentrations of added aluminum (0 and .20% Al) and two of added P (0 and .22% P). The basal diet contained, by analysis, .132% P, .74% Ca, and .021% Al. The calves were assigned to four treatment groups balanced according to body weight. The four treatments were 1) normal P, low Al; 2) low P, low Al; 3) low P, high Al; and 4) normal P, high Al. Calves had ad libitum access to their respective diets for 7 wk. Metabolism of a single oral 32 P dose was determined during wk 6. The adverse effects of high dietary Al include a 17% reduction in feed intake and a 47% reduction in body weight gains. Alkaline phosphatase and plasma glutamic oxaloacetate transaminase activities increased in calves receiving the high Al diets. A negative balance of P and Ca was noted in the calves fed high concentrations of Al. Apparent absorption of 32 P was reduced (37%) in calves fed diets high in Al (44% of dose vs. 69%). Urinary excretion of 32 P was not affected by dietary Al concentrations. Calves fed the low P (deficient) diet showed significant reductions in feed intake, weight gain, serum inorganic P, bone ash, and P content of bone. Dietary P did not significantly affect 32 P absorption. Adding .20% dietary Al severely affects P metabolism and performance of young growing calves.

The two-dimensional steady flow of a gas-particle mixture through an orifice is numerically modeled using the particle-source-in-cell approach. The results show the extent of the recirculation zone behind the orifice and the effect of particles on the gas velocity and pressure distributions. The predicted pressure drop across the orifice agrees favorably with experimental results.

Bioavailability of P from defluorinated phosphate and dicalcium phosphate and the P requirement were studied with 63 male Holstein calves. A P depletion diet containing .08% total P on a dry matter basis was fed to all animals for 4 wk beginning at 6 wk of age and 61kg weight. Calves developed typical signs of P deficiency. The depletion period was followed by a 6-wk experimental period in which the same depletion diet was used as a control. Phosphorus from each of the two sources was added to make diets containing .14, .20, and .32% total P. Source of supplemental P did not affect weight gains, feed consumption, feed efficiency, serum inorganic P, serum alkaline phosphatase, or bone ash. Weight gains, feed intake, feed efficiency, and serum inorganic P were more sensitive measures of dietary P content than were serum alkaline phosphatase or bone ash. Tibia joint ash was a more sensitive measure than tibia shaft ash or rib ash. Growth rate, feed intake, serum inorganic P, and tibia joint ash each increased linearly with increasing dietary P. The data suggest that the P requirement of 2 to 4 mo calves may need to be revised upward.

Drag coefficients of inert and buring metal particles accelerating in gas streams, considering the particles in convective flow behind shock wave in shock tube

The goal of this project is to investigate the potential of the meter configuration consisting of a sharp-edged contraction section followed by an extended length of constant area duct and finally a diffuser section for pressure recovery. This and two other configurations were tested. These configurations and the reasons underlying their selection are described and discussed. It is concluded that Murdock's correlation for steam/water flow through orifices and sudden contraction sections at low qualities is invalid and the metering scheme based on it is inoperative. (MHR)

Thirty dairy cows, fed a control diet consisting of silage and concentrates, were given either 0, 1000, or 2000 ppm of supplemental Zn (DM basis), from zinc sulfate monohydrate (ZnSO4.H2O) for most of a lactation. Feeding 2000 ppm Zn decreased milk yield and feed intake after several weeks. Some cows were affected more severely than others. Generally, primiparous animals were more tolerant of the high Zn diet than multiparous cows. Milk Zn was materially higher for cows fed 1000 ppm added Zn than controls. With 2000 ppm Zn, milk Zn was elevated further but returned to control values when the high Zn diet was discontinued. Plasma Zn was higher in cows fed supplemental Zn with the increase from 1000 to 2000 greater than that for the first addition. Plasma Cu was lower in cows feed 2000 ppm Zn but milk Cu was not reduced. Milk fat content was not affected, but protein and SNF were reduced by the 12th wk with the 2000 ppm Zn diet. There was no apparent effect on long-term health or performance after the cows were removed from the 2000 ppm Zn diet. Except for lower calf weights with 2000 ppm Zn, reproductive performance was not measurably affected by the dietary treatments. The 1000 ppm added Zn diet had no adverse effect on the cows in any parameter measured.

A computational model developed for two-dimensional dispersed two-phase flows is applied to steam--water flow in a sudden contraction. The calculational scheme utilizes the cellular approach in which each cell is regarded as a control volume and the droplets are regarded as sources of mass, momentum and energy to the conveying (steam) phase. The predictions show how droplets channel in the entry region and affect the velocity and pressure distributions along the duct.

The governing equations for a flowing vapor with suspended burning, evaporating, or condensing droplets are derived in a straightforward manner using the control volume, or Reynolds transport, approach. The equations demonstrate how mass transfer at the droplet surface contributes to the momentum and energy of a single droplet, a cloud of droplets, and the vapor phase. The inclusion of boundary droplets gives rise to a droplet heat transfer term omitted in previous derivations. These equations provide a starting point for the development of viable numerical and analytic models for vapor-droplet flows.

The simultaneous measurement of mass flow rate and quality of low-quality steam-water flows is of primary interest in evaluating and monitoring the flow from geothermal resources. The experience acquired at LLL in attempting to perform such measurements with a double flash (meter-valve-meter) arrangement using orifices and venturis is related. The mass flow correlations proposed in the literature are reviewed and a new correlation based on the energy equation is introduced. The data are presented and evaluated in light of these correlations. Directions for future research in this area are suggested.

Metabolism of orally dosed 75 Se was studied in 10 intact male Holstein calves that were fed ad libitum a control diet containing no added Pb or supplemented with 1000ppm Pb as PbSO 4 for 4 wk. Lead-supplemented calves did not exhibit any clinical signs of Pb toxicity. Voluntary feed intake was reduced by 9.5% and average daily gain by 23%. Lead content of rib, liver, and kidney increased. Serum glutamic oxaloacetate transaminase activity was increased during the last 2 wk of the experiment in calves fed Pb. In calves receiving supplemental Pb, 75 Se absorption, blood concentration, and urine concentration were reduced by 26, 21, and 42%, respectively. Tissue 75 Se concentrations were significantly lower in kidney, liver, testicle, pancreas, small intestine, heart, spinal cord, and muscle in calves fed Pb. There was a significant negative correlation (r = −.78) between 75 Se and stable Pb concentrations in the liver. It is not clear whether the ingestion of subclinical amounts of Pb could affect the absorption and utilization of Se in dairy calves to the extent of Se deficiency when dairy calves are kept in areas known to be low in Se.

Sixteen intact male Holstein calves averaging 86 kg and 63 d of age were assigned randomly to four treatment groups. The four treatment diets contained .17, .67, 1.31, and 2.35% Ca on an as-fed basis. The resulting Ca:P ratios with P held constant at about .34% were .47:1, 1.92:1, 3.83:1, and 7.20:1. Calves were fed diets at 3% of their body weights for 4 wk. Magnesium in the bone ash and serum was lowered by the 2.35% Ca treatment. Serum inorganic P was also reduced by the highest Ca diet during the last 2 wk of the experiment. Liver had the highest concentration of Zn in calves fed .67% Ca, and the muscle from calves fed 1.31% Ca diet had the lowest amount of Zn. Copper was reduced in pancreas for 1.31% Ca diet, but Ca was highest in the muscle and heart at the .67% Ca treatment. Weight gains and feed efficiencies were not affected by Ca. Fecal pH was different among treatments and increased as Ca intake increased. Young growing dairy calves can adapt to a wide range of Ca intakes and Ca:P ratios and maintain a moderate growth rate for 4 wk. It appears that excessive dietary Ca may affect concentrations of Zn, Fe, Cu, and Mn in some body tissues, but the magnitude of the effect is relatively small.

This report summarizes the progress made during the first six months of the grant period. The status of each of the three major task areas is discussed: the atomization study, the analytical droplet model, and the combustion study. The time-period has been used primarily to design and begin fabrication of the experimental atomization and combustion facilities. No data is presented in either of these areas. Significant progress has been made in the development of the numerical droplet model. The results of a preliminary parametric study are presented for a single coal particle in a one-millimeter methanol droplet. The importance of gas phase velocity and coal particle diameter bringing the solid material to the droplet surface is discussed.