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Current control systems for the shot peening operation merely rely on old technologies, which often require repetitive processes to obtain pre-validated Almen systems to guide industrial productions. These designs for the manufacturing paradigm are not efficient for complicated workflows in modern manufacturing operation. Thus, in this study, we propose a practical model-based control system to address the issues; especially for a smarter and automated shot peening machine. In particular, the closed-loop control system development utilizes a model-based proportional-integral-derivative (PID) control technology and extreme gradient boosting (XGBOOST) machine learning algorithm. The control system includes an internal process model, a proxy model, a model-based PID controller, and pressure sensors with a low-pass filter for feedback control. The developed control system is integrated into a physical shot peening machine for on-site control validation and demonstration. In both in-silico and on-site control demonstrations, the obtained control performance is stable, robust, and reliable for different operational conditions. The measurement intensities are very close to targeted setting intensities. All the differences are smaller than the industrial threshold of (±0.01 mmA). It implies that the control system can use in industrial peening operations without the need for Almen system development for operational guidance. In other words, the control system can significantly reduce the total cost of the actual production by eliminating the cost, time, and labor of the iterative trials to build the Almen system.

Performance of UV reactors for water disinfection is investigated in this paper. Both experimental and numerical studies are performed on base reactor LP24. Enterobacteria phage MS2 is chosen as the challenge microorganism in the experiments. Experiments are conducted to evaluate the effect of different parameters, i.e. flow rate and UV transmission, on the reactor performance. Simulation is carried out based on the commercial software ANSYS FLUENT with user defined functions (UDFs) implemented. The UDF is programmed to calculate UV dose absorbed by different microorganisms along their flow trajectories. The effect with boundary layer mesh and without boundary layer mesh for LP24 is studied. The results show that the inclusion of boundary layer mesh does not have much effect on the reactor performance in terms of reduction equivalent dose (RED). The numerical results agree well with the experimental measurements, hence validating the numerical model. With this achieved, the numerical model is applied to study other scaled reactors: LP12, LP40, LP60 and LP80. Comparisons show that LP40 has the highest RED and log inactivation among all the reactors while LP80 has the lowest RED and log inactivation.

The evolution of the microstructure and the surface residual stress upon controlled gaseous nitriding of quenched and tempered 31CrMoV9 steel was investigated by varying the nitriding potential and the nitriding time at the nitriding temperature of 550 °C. A graded microstructure developed as a function of depth: a surface adjacent decarburized-nitrided zone, in which all tempering induced carbides had trans-formed to nitrides, under loss of the released carbon through the surface, is followed by a nitrided zone in which the carbon released from the carbide-to-nitride transformation had diffused to grain boundaries and precipitated there as (new) carbides. The extent of decarburization showed a strong dependence on whether or not an outer iron-nitride compound layer was present, as well as on the type of iron nitride present at the specimen surface. The surface residual stresses varied as a function of nitriding time and nitriding potential which has been discussed in terms of the rates of the carbide-to-nitride transformation, the decarburization and/or the carbide pre-cipitation along the grain boundaries.

Internal nitride development in iron-based quaternary Fe-Cr-Mo-V alloy, as a model alloy for 31CrMoV9 steel, was investigated by performing controlled gaseous nitriding experiments. The nitride-precipitation process starts with the development of nanosized platelets of, coherent, cubic NaCl-type nitride, along {100} lattice planes of the ferrite matrix, in association with matrix-lattice dilation. The development of nitride platelets having a NaCl-type crystal structure, satisfying the Baker–Nutting orientation relationship with the ferrite matrix, and the nitrogen content of the nitrided zone suggest the development of a quaternary “mixed” (Cr x ,V y , Mo1−x−y)N nitride, similar to the development of “mixed” ternary nitrides as reported for nitrided Fe-Cr-Al and Fe-Cr-Ti alloys. In a later stage, the nitride platelets undergo discontinuous coarsening resulting in the development of a lamellar microstructure consisting of nitride and ferrite lamellae. Kinetic analysis demonstrated that the thermally activated nature of growth of the diffusion zone is controlled with about equal weights, by the diffusion of nitrogen in the substrate matrix and the matrix lattice solubility of nitrogen.

Ultraviolet (UV) reactor for ballast water treatment is investigated in this paper. Experimental and numerical simulations are performed for a base reactor named LBW850e. B. Pumilus is chosen as a challenge organism in the experiments. Simulation is carried out based on the commercial software ANSYS FLUENT with user defined functions implemented. The effects of water flow rate and UV transmittance (UVT) on the UV reactor performance in terms of reduction equivalent dose (RED) are studied. The results show that the increase of water flow rate reduces RED. While RED increases with the increase of UVT. The experimental and simulation results show reasonable agreement with each other. With this achieved, the numerical model developed in the current work can be applied to other reactors.

This research was conducted to compare the meat characteristics of Korean native duck and imported commercial duck. The Korean native ducks and imported commercial ducks (broiler duck: Grimaud) were raised under identical rearing and feeding conditions for 8 wk and 6 wk, respectively. At the end of the rearing period, ten ducks from each group were slaughtered, and breast and leg meat were obtained 24 h after slaughtering for analyses of meat characteristics. The results showed that the breast of Korean native ducks contained lower moisture and fat, and higher protein and water holding capacity (WHC) than those of imported commercial ducks (p

Division of Animal Care, Cheonan Yonam CollegeABSTRACT This experiment was conducted using 350 Lohmann Brown layers (67 weeks of age) to evaluate the dietary effect of organic or inorganic Se and Cu on their contents in chicken eggs. The layers were divided into seven groups and fed a commercial diet or one of the six experimental diets containing different levels of Se and Cu (T1, 0.3ppm organic Se; T2, 1.0ppm organic Se; T3, 1.0ppm inorganic Se; T4, 125ppm organic Cu; T5, 250ppm organic Cu; and T6, 250ppm inorganic Cu) for 5 weeks. No significant differences were observed in egg production and its qualities among groups. The contents of blood cholesterol in the birds fed various levels of Se and Cu were not significantly different as compared to control. Se contents in eggs were linearly increased as dietary Se levels increased for both sources, but Se contents from the groups fed organic Se were slightly higher than those fed inorganic Se. Sensory characteristics of eggs were not influenced by dietary treatments. In conclusion, Se contents in eggs were linearly increased as dietary levels of organic or inorganic Se increased, but eggs in layers fed the diet containing organic Se did not show higher Se contents than those in birds fed dietary inorganic Se.(Key words : selenium, copper, laying performance, transfer, laying hens)

This study was carried out to investigate dietary effects of extracts of Skullcap (Scutellaria baicalensis) (SCE) grown in Korea on growth performance, immune and physiological responses in broiler chickens. Total of seven-hundred fifty 1-d-old Ross male broiler chicks were divided into five groups and fed control diets (antibiotics medicated or non-medicated commercial diets) or each experimental diet (non-medicated diets containing 0.1, 0.3 or 0.5% SCE) for 5 weeks. The body weight gain and feed conversion rate in the groups fed diets containing 0.1% or 0.3% SCE were significantly improved as compared with those of non-medicated control group (P

The mechanical properties of the vinyl ester reinforced with oil palm of empty fruit bunch fibers (EFB) laminated at different layer arrangements with glass fiber (CSM) composites were investigated. The EFB and CSM fibers were laminated at different layer arrangements and then were impregnated with vinyl ester resin using resin transfer molding (RTM). Post-cure was carried out after cool press for about 24 h in an oven at 50°C. Six different layers of lamination with a ratio of 50/50 fiber composite (50% EFB and 50% CSM) were manufactured. Control fiber composites with 100% mechanical fibers, 100% chemical fibers and 100% glass fibers were investigated for comparison. The mechanical properties (tensile, flexural, and impact test) and physical properties (water absorption, dimension stability, and density) were analyzed. The mechanical properties, water absorption, and density of hybrid composites exhibited higher properties than control composites (chemical and mechanical fibers). While comparing the layers of orientation of hybrid composites, the results of the tensile and flexural tests showed that composites with glass fiber at the outer layer showed higher tensile and flexural properties than the others. The impact test and the composites with natural fibers in the outer layer showed the highest results as compared to other layer laminations. However, hybrid composites exhibited comparable properties as compared to glass fiber composites, alone.

The aim of the present study was to delineate the expression and secretion of insulin-like growth factor (IGF) system components by pig liver cells. Hepatocytes were prepared from 3-wk-old weanling piglets following a two-step collagenase perfusion procedure, after which the cells were incubated for 24 or 48 h at a density of 2×10 5 cells per 35-mm dish in 2-ml Williams' medium E. The cells were found to express the genes encoding IGF-I, IGF-binding proteins (IGFBPs)-2 and -3 and acid-labile subunit (ALS) by reverse transcription-polymerase chain reaction (RT-PCR) following the culture. However, IGF-I was localized to hepatocytes by immunohistochemical analysis, whereas IGFBP-3 was localized to endothelial cells, but not to hepatocytes. This indicated that the IGFBP-3 gene expression detected by RT-PCR was likely to have been contributed by unidentified non-parenchymal cells that had not been removed during the hepatocyte preparation. The conditioned culture medium (CCM) of the cells contained immunoreactive IGF-I and IGF-II, with the latter being seven-fold more abundant than the former. The CCM also contained 43-, 40-, 34-, 31-kDa doublet and 26-kDa IGFBPs as examined by Western ligand blotting. The 40-, 34- and 31-kDa doublet IGFBPs were approximately three-fold as abundant as the 43- and 26-kDa IGFBPs. Moreover, the 43- and 40-kDa doublet and the 34-kDa IGFBPs were immunoprecipitable with IGFBP-3 and IGFBP-2 antibodies, respectively. Overall, these results are similar to those known in the rat, which suggests that the IGF system components are likely to be expressed and secreted in pig liver in a manner similar to that in rat liver. (Key Words : IGF, IGFBP, Gene Expression, Hepatocyte, Pig)

In the plasma spray coating process, the coating’s profile and overall thickness are dependent on the number of overlapping traverses of the torch, the shape of the particle spray plume, the spatial distribution of the in-flight parameters of the particles within, and the orientation of the substrate. In this paper, a semi-empirical methodology for predicting three-dimensional deposits by the plasma spray process is developed. It comprises of three stages: first, spatial distributions of the in-flight parameters of multi-sized particles within the spray plume are determined by Computational Fluid Dynamics simulations. The size and shape parameters of the splats formed when individual droplets impact and spread out are obtained by experiments. Finally, a computer program is developed to integrate the particle parameters distribution and the empirical splat geometric data to generate a three-dimensional profile representing the deposit. The procedures predict the deposition volumes and thicknesses for different substrate inclinations with good agreement to experimentally sprayed deposits.

Two experiments were conducted to evaluate the feeding values of red pepper seed oil meal (RPSOM) and to investigate its dietary supplementation on broiler performances. In Exp. 1, nutritional values of RPSOM were evaluated by analyzing chemical composition and determining true metabolizable energy (TME), nitrogen corrected TME (TMEn) and true available amino acid (TAAA). RPSOM contained 22.50% of CP, 4.75% of ether extract, 27.70% of crude fiber, 4.73% of crude ash and 49.97 ppm of xanthophylls. The contents of capsaicin and dihydrocapsaicin were 34 mg and 31 mg/100 g DM, respectively. The values of TME and TMEn determined by force-feeding 16 roosters were 1.73 kcal/g and 1.63 kcal/g DM, respectively. The average TAAA value of 17 amino acids was 85.22%. In Exp. 2, a total of 225 Ross male broiler chicks, 3 weeks old, were randomly divided into 9 groups of 25 birds each and assigned to three experimental diets containing 0 (control), 5 or 10% RPSOM fed ad libitum for 3 weeks. No significant differences were observed in growth performances and carcass characteristics. The level of serum cholesterol in the 10% RPSOM group was significantly lower than that of the control group (113.92 vs. 137.50 mg/dl). The dietary RPSOM at 5 and 10% levels increased the content of C18:2ω6 in leg muscle compared with the control group. The results suggested that RPSOM can be included into broiler feed up to 10% without any negative effects on broiler performances and physiological responses and used as a non-conventional plant protein source, if its nutritional values are well evaluated.

In this research, the combination of oil palm fiber and glass fiber as reinforcing fibers in polyester composites was evaluated. The mechanical and physical properties of oil palm empty fruit bunch/glass hybrid reinforced polyester composites were studied. Hybrid laminate composites with different weight ratios (w/w) of chopped strand mat (CSM) glass fibers: oil palm empty fruit bunch fiber (EFB) 3: 7, 5: 5, 7: 3, 9: 1 were prepared. The hybrid effect of glass and EFB fibers on the tensile, flexural, impact, and hardness of the composites were investigated. Water absorption and thickness swelling were also conducted. In general the hybrid composites exhibited good properties compared to the EFB/polyester composites.

Numerical models have been developed using computational fluid dynamics (CFD) analysis program FLUENT V6.02© to investigate the effect of the substrate on the behavior of the plasma flow fields and in-flight particles. Simulations are performed for cases where flat substrates are either present or absent, for the former, the substrate is oriented perpendicularly or inclined to the torch axis. It is shown that although the presence of perpendicular or inclined substrate significantly influences the plasma flow fields at the vicinity of the substrate, the particle behavior remain relatively unaffected. The insignificant effect of the substrate on particle behavior is qualitatively verified by experimental observation using SprayWatch© imaging diagnostics equipment. Images captured by the equipment confirm that the particles travel through the plasma plume with high momentum and show no sudden change in theirtrajectories right before impacting the substrate. Both the numerical and experimental findings show that the freestream model is sufficiently detailed for future work of this nature.

Real time close-up images of in-flight particles plasma sprayed onto a substrate and in freestream condition (without substrate present) are captured. Besides the images, particle behavior in terms of temperature, velocity, and heading are measured by the Spray Watch particle imaging diagnostics system. The monitoring and measurement of particle behavior have been performed for substrates inclined at various angles to investigate the effect of the substrate on particle behavior. The close-up images show that particles propelled from the torch travel with high momentum and are not affected by the substrate and inclination angle. Quantitative analyses of the particle average velocity and heading data with and without the different inclined substrates also lead to similar conclusions. The particle velocity is resolved into tangential and normal velocity components parallel and perdendicular to the substrate, respectively. The tangential velocity component controls the degree of splat elongation into elliptical shape from the circular shape seen in perpendicular impact. This is of practical importance in industrial spraying of engineering components of complex curvatures. A higher tangential velocity component also implies that more powders are lost through rebounding and overspraying and thus reducing the deposition efficiency. The normal velocity component decreases when substrate inclination increases, which tends to weaken the coating adherence.

The effects of dietary sources of C18:2 n-6 or C18:3 n-3 fatty acids on the occurrence of conjugated linoleic acid (CLA) and time-dependent changes of free fatty acid fractions in rumen contents were investigated. Sheep (n=4) fitted with rumen fistula were used in a 44 Latin square design with each 14 d period. Sheep were fed one of four diets consisting of grass hay and concentrates in a ratio of 70:30. Dietary treatments were 100% concentrates (served as the control), and concentrates were replaced by safflower seed at 30% (SFS), safflower meal at 18% - safflower oil at 12% (SFO), and safflower meal at 18%-linseed oil at 12% (LNO). At the end of each experimental period, rumen contents from each sheep were collected before feeding and at 1, 3, 6 and 12 h after feeding. The levels of cis-9, trans-11 CLA in free fatty acid fraction were considerably increased in all treated groups relative to the control, but not significantly. The increase in cis-9, trans-11 CLA was slightly higher in SFS and SFO groups than group fed diet containing linseed oil. The level of cis-9, trans-11 CLA in free fatty acid fraction was reached to the maximum value at 1hr after feeding and, thereafter gradually decreased to near the value before feeding. The generation of trans-11 C18:1 was significantly higher in all treated groups than that of control. The level of trans-11 C18:1 was linearly increased after feeding of experimental diets, reaching the maximum value at 3 h. Feeding of diets containing polyunsaturated fats to sheep resulted in a marked increase in the levels of trans-11 C18:1 and a slight increase of CLA in free fatty acid fraction of rumen contents. Our results support that endogenous synthesis of CLA from trans-11 C18:1 may be involved the primary source of CLA in dairy product. (Asian-Aust. J. Anim. Sci. 2003. Vol 16, No. 2 : 222- 226)

The effects of dietary conjugated linoleic acid (CLA) on lipid concentrations and fatty acid composition of various tissues were studied in young chicks. From 7 days of age, a total of 160 chicks were divided into 4 groups, placed into 4 pens per group (10 birds per pen) and fed one of four experimental diets containing 6% tallow (TO 6%), 4% tallow plus 2% CLA (TO 4%-CLA 2%), 2% tallow plus 4% CLA (TO 2%-CLA 4%) or 6% CLA (CLA 6%) for 3 weeks. There were no significant differences in growth performances and the relative weights of various organs, but relative liver weight of chicks fed dietary CLA at 4 and 6% levels was significantly higher (p

Inter-simple sequence repeats (ISSR) polymorphism was used to determine genetic relationships among 75 Sesamum indicum L. accessions of Korean and exotic sesame. Fourteen reliable ISSR primers were selected for the assessment of genetic diversity, yielding 79 amplification products. Of these polymerase chain reaction products, 33% revealed polymorphism among the 75 accessions. Genetic distances ranged from 0 to 0.255, with a mean genetic distance of 0.0687. The 75 accessions were divided into seven groups on the basis of unweighted pair-group method with arithmetic averages (UPGMA) cluster analysis. The largest group consisted of 25 Korean cultivars, eight Korean breeding lines and 17 world-wide accessions. The other groups included 25 accessions, several of which contained useful traits. The dendrogram did not indicate any clear division among sesame accessions based on their geographical origin. However, all Korean sesame cultivars except ‘Namsankkae’ were clustered in the same group, indicating a narrow gene pool. Some of the Korean breeding lines were spread along the dendrogram, showing enlargement of genetic diversity. The genetic diversity data uncovered in this study can be used in future breeding programmes.

At the design stage, the work reported here recommends provision of the possibility of employing modern on-line spectral condition-monitoring equipment in order to improve the operational availability of nuclear power plant equipment, the reactor coolant pump (RCP). Following an analysis of the leading causes in the RCP forced outages, incorporation of the use of advanced on-line spectral condition-monitoring sensors and their corresponding data-processing equipment in new power plant designs is sought. They are employed in order to detect the incipient symptoms generated during the progression of potential system faults of major concern. Firstly, the applicability of recent developments in new sensors and data-processing techniques is examined. This examination concerns system status parameter monitoring in the analysis of vibration, motor current, partial discharge and wear debris. Finally, use of modern sensors and data-processing equipment, which are valuable for the intended condition-monitoring systems, is recommended. Furthermore, valuable information on the future trend of currently developing sensors at the research stage is briefly presented. This state-of-the-art review lays a foundation for developing modern comprehensive sensor networks to support efficient condition monitoring in other power plant rotating machines.

The work presented here presents an evaluation method for the question of how reliably the system (or component), responsible for the dominant plant availability loss, will run in an extended 48 month operating cycle. As major contributors to the total plant forced outage time in pressurized water reactors (PWRs), reactor coolant pumps (RCPs) and main feed pumps (MFPs) are chosen as specific example systems for a case study. The method proposed estimates the expected forced outage length contribution of each system to the maximum allowed outage length given a certain plant capacity factor. Based upon the current reliability level estimated from the Nuclear Regulatory Commission plant performance database, the assessment of each system impact shows that 14.2 and 2.2 per cent of the maximum allowed outage length are expected to be taken by RCPs and MFPs respectively in the PWR regardless of other systems. In order to meet a 97 per cent goal capacity factor to be envisaged in a 48 month operating cycle, it is recommended that various possible actions be devised for achieving the higher RCP and MFP operational availability through design, monitoring and maintenance.

The rapid advancement of powerful monitoring devices and computers permits one to design a comprehensive sensor network as the foundation of an efficient plant condition monitoring and diagnosis system. For the development of such a comprehensive sensor network in complex power plant systems, the work presented here describes the rationale and implementation of an integrated method incorporating a structural system hierarchy and a functional system hierarchy, a fault–symptom matrix, sensor selection criteria, use of a sensor installation feasibility study, and advanced instrumentation steps. In selecting instrumentation to use we include the state of the art technologies concerning data processing and data integration as a means of extending the plant's feasible diagnostic coverage. The application of the design technique described here to the specific example component of the turbine generator demonstrates how each step of the presented method contributes to completion of the sensor network development in a systematic way.

This study was conducted to compare growth performance, carcass characteristics and meat quality of 4 breeds of local chicken. A total of 480 1-d-old chicks were distributed to 16 pens, with 4 treatments of breed, 4 replicates and 30 chicks per pen. Three Korean local breeds of white-mini broiler, Hanhy-up-3-ho, and Woorimatdag, and a breed of silky fowl were raised under identical rearing and feeding conditions for 31-d, 37-d, 36-d, and 59-d, respectively. The BW and feed consumption on a pen basis were weekly measured for all pens, and ADFI, ADO and gain:feed were calculated for each pen. The ADFI and ADO of 3 breeds of Korean local chicken were greater than those of silky fowl (p

Haemangiomas in children usually involute spontaneously and surgical treatment is exceptional. Vascular malformations do not regress spontaneously and resection may become necessary. We present a series of surgically treated face and neck vascular anomalies during a 9-year period, assessing the epidemiology, presenting signs and symptoms, diagnostic modalities, indications for surgery, treatment methods and clinical outcome post-treatment.The medical and pathological records of all patients with cervicofacial vascular anomalies treated surgically at our department from 1997 to 2005 were retrospectively reviewed in relation to current evidence.Forty-one patients were identified. Of these, 9 patients had haemangiomas and the remaining 32 had a variety of vascular malformations. Cervicofacial vascular anomalies were most commonly located at the lip. Atypical looking vascular anomalies like masseteric intramuscular haemangiomas and parotid malformations were diagnostic problems. All 41 had surgical excision of their vascular anomalies for troubling symptoms, cosmesis or diagnostic purpose. For cervicofacial arteriovenous malformations, 28% were classified as Schobinger stage I, 50% stage II, and the remainder stage III. Combined embolisation-resection was used to treat 6 arteriovenous malformations (stage II to III) and of these, 3 required flap reconstruction.Accurate diagnosis distinguishing between cervicofacial haemangiomas and vascular malformations is key to best treatment. The diagnosis can usually be made by history and physical examination aided by early magnetic resonance imaging (MRI). Although cervicofacial haemangiomas can be managed conservatively or with medical therapy, surgery is indicated for preventing psychological distress and in cases of chronic aesthetic alteration resulting from partial regression. Aesthetic concerns and prevention of psychosocial distress point to early excision of venous malformation as the treatment of choice. Lymphatic malformations are best treated by excision. Outcome after excision of localised cervicofacial haemangiomas and low-flow vascular malformations is excellent. Large extensive low-flow malformations as well as those located at the lips may require multiple procedures including reconstruction; patients should be informed that the outcome is generally not as good. Combined embolisation-resection is definitive treatment for arteriovenous malformations and flap reconstruction may prevent their recurrence. Tissue expansion is a useful reconstructive tool after the excision of large vascular anomalies.

We present a series of head and neck extracranial non-vestibular schwannomas treated during a ten-year period, assessing epidemiology, presenting signs and symptoms, location, nerve of origin, diagnostic modalities, treatment and clinical outcome.Clinical records of all patients with head and neck schwannomas treated at our department from April 1995 to July 2005 were retrospectively reviewed.There was female predominance (67%). The mean age at diagnosis was 48 years. Sixteen (76%) presented with a unilateral neck mass. Eleven schwannomas (52%) were in the parapharyngeal space. The most common nerves of origin were the vagus and the cervical sympathetic chain. The tumour may masquerade as a cervical lymph node and other myriad conditions. Treatment for all but 2 cases was complete excision with nerve preservation. Two cases of facial schwannoma required sacrifice of the affected nerve portion with nerve reconstruction. All facial schwannoma patients suffered postoperative facial palsy with only partial resolution (mean final House-Brackman grade, 3.25/6). Among non-facial schwannoma patients, postoperative neural deficit occurred in 12 with partial to complete resolution in 7. The median follow-up period was 24 months. No schwannoma was malignant and none recurred.Non-vestibular extracranial head and neck schwannomas most frequently present as an innocuous longstanding unilateral parapharyngeal neck mass. Preoperative diagnosis may be aided by fine-needle cytology and magnetic resonance imaging or computed tomographic imaging. The mainstay of treatment is complete intracapsular excision preserving the nerve of origin, but for extensive tumour or facial schwannomas, subtotal resection or nerve sacrifice with reconstruction and rehabilitation are considerations. Surgery on intraparotid facial schwannomas carries considerable morbidity and conservative management has a place in treatment. Early recognition of facial schwannomas is key to optimal treatment.

The complex ({eta}{sup 5}-C{sub 5}H{sub 5})(CO){sub 2}FeC{triple bond}CC{triple bond}CH was prepared by sequential treatment of LiC{triple bond}CC{triple bond}C-Si(CH{sub 3}){sub 3} with ({eta}{sup 5}-C{sub 5}H{sub 5})(CO){sub 2}FeCl and tetrabutylammonium fluoride. The monometallic complexes ({eta}{sup 5}-C{sub 5}H{sub 5})(CO)-LFeC{triple bond}CC{triple bond}CH (L = CO, PPh{sub 3}) were deprotonated with sec-BuLi, and the resulting anions were trapped with ({eta}{sup 5}-C{sub 5}H{sub 5})M(CO){sub n}Cl to form ({eta}{sup 5}-C{sub 5}H{sub 5})(CO)LFeC{triple bond}CC{triple bond}CM-(CO){sub n}({eta}{sup 5}C{sub 5}H{sub 5}) (n = 2, M = Fe, L = CO, PPh{sub 3}; n = 3, M = Mo, L = CO, PPh{sub 3}; n = 3, M = W, L = CO, PPh{sub 3}) in 55-86% isolated yield. IR data suggest that the butadiynediyl ligand is effective in conveying electronic information between the two metal centers of the bimetallic molecules.

Combustion-aided suspension plasma spraying (SPS) was developed for the synthesis of Y2O3 nanoparticles. Numerical models for Ar, Ar∕O2, and combustion-aided plasma fields were built using FLUENT V6.3.2© to compare their different plasma thermophysical properties. Modeling and experimental results both indicate that the plasma field was substantially altered by combustion-aided SPS. The plasma exhibited an elevated volume average temperature and reduced velocity as well as a broadened plasma plume, which resulted in an enhanced vapor supersaturation degree and a faster quenching rate in the radial direction. These can be attributed to the dual effects of oxygen dissociation/recombination and acetone solvent combustion. Consequently, productivity of the obtained nanoparticles increased remarkably and the particles’ morphology was improved, with a smaller mean particle size and a narrower size distribution in comparison with those of powder feeding spraying. Furthermore, plasma-induced cubic→monoclinic phas...

Two experiments were conducted to determine the effect of choline supplementation on corn-soy-meat-based grower and laying hen diets. Diets contained 2.5% and 3% meat and bone meal in the growing and laying diets, respectively, and on chemical analysis contained 1005 and 1041 ppm of choline respectively. In the first experiment, 1000 ppm of choline were added to the basal growing and laying diets, and in the second experiment the laying diet was supplemented with 550 ppm or 1000 ppm of choline. In both trials, choline supplementation did not increase gains or feed efficiency for pullets from 8 to 20 weeks. However, choline supplementation during the laying period resulted in a statistically significant improvement of egg production and egg size. Supplementation of choline in the growing phase did not affect the laying performance. Laying performance was not improved by 2 μg/kg of supplementary vitamin B12 in a 1000 ppm choline supplement diet (78% vs. 76% hen-day production). In the second trial, added levels of choline (0, 500, and 1000 ppm) resulted in egg production from 24 to 64 weeks of 73, 76, and 76% hen-day production, respectively. Egg weights were 59, 61, and 61 g, respectively. This suggests that the total choline requirement of laying hens on a corn-soy-meat diet, and in absence of supplementary methionine, is greater than 1000 ppm but no more than 1500 ppm.

The efficiency of alpha-ketoisocaproate as a dietary substitute for leucine was assessed in rats by two techniques: first, the minimal dose of alpha-ketoisocaproate required, as a supplement to a leucine-free diet, to achieve a growth rate as great as animals receiving leucine was found to be between 2.2 and 4.4 times larger. Therefore the nutritional efficiency of alpha-ketoisocaproate lies between 0.23 and 0.46. Second, alpha-[1-14C]-ketoisocaproate and [3H]leucine were administered orally and the ratio of 14C/3H incorporated into the leucine of whole-body protein and fibrin was measured. This ratio, divided by the ratio 14C/3H injected, was the same in fibrin as in whole-body protein and averaged 0.39. Thus both techniques yield the same value, within the error of measurement, for the relative nutritional efficiency of alpha-ketoisocaproate. We also found that alpha-ketoisocaproate feeding at varying dosage did not alter this ratio in whole-body protein (measured in rats fasted overnight), suggesting that neither wide variations in growth rate nor exposure for 10 days to alpha-ketoisocaproate (in a diet of constant protein content) alters the relative rates of utilization (or oxidation) of alpha-ketoisocaproate vs. leucine.

Protein turnover and DNA and RNA levels were measured in the breast (pectoralis thoracica) and leg (gastrocnemius-peroneus) muscles of large white (Nicholas strain) turkey poults from 1 to 8 weeks of age to investigate their cellular growth and to evaluate the influence of protein turnover on muscle growth. Fractional rates of protein deposition (kg) were determined from regression equations of muscle size and protein content on body weights. Protein synthesis rates (ks) were measured by an isotope emulsion technique. Protein degradation rates (kd) were estimated by the difference between ks and kg. Muscle growth involved increases in total deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), an increase in the DNA-unit size, and decreases in concentrations of the nucleic acids without changes in the RNA:DNA ratio or RNA and DNA activity. The muscles showed developmental changes in ks from 56 to 10%/day and from 38 to 13%/day in breast and leg, respectively, over the 7-week period. The fractional degradation rate also fell from 22 to 7%/day in the breast muscle and from 21 to 10%/day in the leg muscle. The disproportionate decline of ks and kd resulted in an age-associated fall in kg from 34 to 4%/day and from 18 to 3%/day in the breast and the leg muscles, respectively. The efficiency of protein deposition decreased from 61 to 35% in breast muscle and 46 to 20% in leg muscle. The results were qualitatively similar to those obtained in a study with broiler chicks.

The new bridging complexes Cp 3 UClClAlCl 2 and Cp 3 UClClAlCl 2 ·THF were synthesized by reaction of triscyclopentadienyl uranium chloride with aluminum trichloride in the presence of different solvents. The Cp 3 UClClAlCl 2 ·THF complex id proposed to have a square bipyramidal structure with THF occupying the sixth position. A new inorganic cyclooctatetraene uranium complex, UCl 2 (S 4 N 4 ), was also synthesized by uranium tetrachloride with tetrasulfur tetranitride.

The new bridging complexes Cp 3 UClClAlCl 2 and Cp 3 UClClAlCl 2 ·THF were synthesized by reaction of triscyclopentadienyl uranium chloride with aluminum trichloride in the presence of different solvents. The Cp 3 UClClAlCl 2 ·THF complex id proposed to have a square bipyramidal structure with THF occupying the sixth position. A new inorganic cyclooctatetraene uranium complex, UCl 2 (S 4 N 4 ), was also synthesized by uranium tetrachloride with tetrasulfur tetranitride.