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91.
BM Gerlach TA Houser LC Hollis MD Tokach JC Nietfeld JJ Higgins GA Anderson BL Goehring 《Meat science》2012,92(4):805-807
Nursery-age pigs (n=198) were used to evaluate the difference in abscess formation at needle-free jet and conventional needle-and-syringe injection sites. Needle-free jet injection was used to administer injections in the neck and ham on one side of the animal whereas needle-and-syringe was used for neck and ham injections on the opposite side. Immediately prior to injection, the injection site surfaces were contaminated with an inoculum of Arcanobacterium pyogenes. Each pig was humanely euthanized 27 or 28days after injections. Histopathological results showed that needle-free jet injection was associated with more abscesses than needle-and-syringe injection at both neck (P=0.0625) and ham (P=0.0313) injection sites. Out of 792 injection sites, only 13 abscesses were observed, with 12 of those present at needle-free jet injection sites. Needle-free jet injection may increase the occurrence of injection site abscesses that necessitate carcass trimming at pork processing plants. 相似文献
92.
Flight tunnel and electrophysiological assays with male Choristoneura rosaceana Harris (Lepidoptera: Tortricidae) were conducted to investigate the non-competitive mechanisms of communication disruption caused by microencapsulated (MEC) (Z)-11-tetradecenyl acetate (3M MEC-LR) formulated with and without horticultural oil (Purespray Green). Male C. rosaceana were exposed for 1 h by resting on metal surfaces sprayed with either water, 2% oil in water, MEC-LR in water, or MEC-LR + 2% oil in water. In one experiment, sprayed surfaces were allowed to age up to 47 days in a laboratory fume hood prior to moth exposure to examine the effect of ageing on the disruptive efficacy of the formulations. In flight tunnel assays with calling females, males exposed to MEC or MEC + oil treatments for 1 h were significantly disrupted up to 1 h after exposure, and both treatments were effective for 47 days. Electroantennograms revealed no reduction in antennal sensitivity when measured 75 s after a 1-h exposure. Collectively, these results support habituation as a key mechanism of communication disruption for C. rosaceana exposed to the MEC formulations tested here. Male proximity to the pheromone-treated surfaces appears to be important in maintaining a disruptive effect as MEC treatments age and pheromone release rates decline. The addition of 2% oil increased the number of microcapsules deposited on sprayed surfaces and caused a moderate but significant increase in the disruptive effect of the MEC formulation. A better understanding of the mechanisms that underlie disruption by MEC formulations, and how an adjuvant like horticultural oil may enhance these mechanisms, may lead to improvements in this technology. 相似文献
93.
94.
Ceramic Powder Synthesis by Spray Pyrolysis 总被引:12,自引:0,他引:12
Gary L. Messing Shi-Chang Zhang Gopal V. Jayanthi 《Journal of the American Ceramic Society》1993,76(11):2707-2726
A variety of spray pyrolysis (SP) techniques have been developed to directly produce ceramic powders from solutions. This paper reviews the current status of these processes in terms of the process parameters that enable the formation of particles with controlled morphology and composition. A model incorporating solute diffusion in the droplet and solvent evaporation from the droplet surface is presented to establish the critical parameters leading to solid particle formation. The model illustrates that solid particles can be obtained if solutes with high solubility and a large difference between the critical supersaturation and equilibrium concentration are used and if the process is designed to avoid solvent boiling. It is demonstrated that mixed metal oxide, non-oxide, and composite particles that are solid, hollow, porous, or fibrous can be produced by modifying the precursor characteristics, solution properties, and process parameters. The physical and chemical flexibility of SP processes offers numerous opportunities for the controlled synthesis of advanced ceramic powders and films. However, production rates are limited by the need to produce < 5-μm-diameter droplets and to avoid subsequent droplet coagulation. Developments in process controls, atomization, and system design are required for wider commercialization of SP-type processes. 相似文献
95.
Tomáš Syrový Stanislava Maronová Petr Kuberský Nanci V. Ehman María E. Vallejos Silvan Pretl Fernando E. Felissia María C. Area Gary Chinga-Carrasco 《应用聚合物科学杂志》2019,136(36):47920
Cellulose nanofibril (CNF) films were prepared from side streams generated by the sugarcane industry, that is, bagasse. Two fractionation processes were utilized for comparison purposes: (1) soda and (2) hot water and soda pretreatments. 2,2,6,6-Tetramethylpiperidinyl-1-oxyl-mediated oxidation was applied to facilitate the nanofibrillation of the bagasse fibers. Poly(ethylene glycol) (PEG) was chosen as plasticizer to improve the ductility of CNF films. The neat CNF and biocomposite films (CNF and 40% PEG) were used for fabrication of self-standing humidity sensors. CNF-based humidity sensors exhibited high change of impedance, within four orders of magnitude, in response to relative humidity (RH) from 20 to 90%. The use of plasticizer had an impact on sensor kinetics. While the biocomposite film sensors showed slightly longer response time, the recovery time of these plasticized sensors was two times shorter in comparison to sensors without PEG. This study demonstrated that agroindustrial side streams can form the basis for high-end applications such as humidity sensors, with potential for, for example, packaging and wound dressing applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47920. 相似文献
96.
Raphaël Faure Fabrice RossignolClaire Bonhomme Alexandre MaîtreGrégory Etchegoyen Pascal Del GalloDaniel Gary 《Journal of the European Ceramic Society》2011,31(3):303-312
The manufacture and the characterisation of alumina foams as alternative catalysts supports for industrial steam reforming processes are presented here. The possibility of use of alumina foams as catalysts supports in such processes is evaluated by studying their resistance toward mechanical and chemical stresses. The alumina foams produced are characterised owing to their processing parameters (slurry infiltration, sintering temperature, template pore size). Their ability to work in hydrothermal atmosphere is assessed by characterising the evolution of microstructures and mechanical strengths upon aging. Thermodynamic studies of the stability of alumina in industrial steam reforming working conditions are performed and correlated to the experiments to demonstrate the stability of such a system. 相似文献
97.
The purpose of surface treatment (conditioning) methods on dental ceramics is to improve the retention and bonding between the enamel or the dentin and ceramic veneer, with the help of resin composite luting cements. These types of surface treatments include chemically altering the surface of ceramics with some specific acidic etchants followed by applying a silane coupling agent (silane). The silane currently used in dentistry is 3-methacryloxypropyltrimethoxysilane, a hybrid organic–inorganic trialkoxy ester monomer, which is diluted in an acidified water-ethanol solvent system. Such silane primers are said to be pre-hydrolyzed. Some oxide ceramics with high crystalline content, such as alumina and zirconia, cannot be easily etched with acid etchants. They should be silica-coated and silanized prior to bonding. A silane coupling agent should be applied after silica-coating to the ceramic surface to achieve chemical bonding and the optimal durable bond strength. 相似文献
98.
Golsa Samii-Saket Jeffrey G. Boersma Gary R. Ablett Duane E. Falk Ron Fletcher Istvan Rajcan 《Journal of the American Oil Chemists' Society》2011,88(11):1795-1798
Development of high oil soybeans would reduce the cost of soybean oil production for biodiesel or edible oil applications. An accurate determination of soybean seed oil concentration is essential especially when developing superior cultivars with increased seed oil content. The objective of this study was to develop an oil measurement method for single seeds using NMR spectrometry. An NMR spectrometer was calibrated using commercial cooking oil. Fifteen cultivars of known mean oil content were used to evaluate the calibration curves. The calibration curves developed had a correlation coefficient of 0.99. It was found that soybean and corn oil gave identical results over the calibrated interval. 相似文献
99.
100.
Identification and Optimization of 4‐Anilinoquinolines as Inhibitors of Cyclin G Associated Kinase 下载免费PDF全文
Dr. Christopher R. M. Asquith Prof. Dr. Tuomo Laitinen James M. Bennett Dr. Paulo H. Godoi Dr. Michael P. East Dr. Graham J. Tizzard Prof. Dr. Lee M. Graves Prof. Dr. Gary L. Johnson Ronna E. Dornsife Carrow I. Wells Dr. Jonathan M. Elkins Prof. Dr. Timothy M. Willson Prof. Dr. William J. Zuercher 《ChemMedChem》2018,13(1):48-66
4‐Anilinoquinolines were identified as potent and narrow‐spectrum inhibitors of the cyclin G associated kinase (GAK), an important regulator of viral and bacterial entry into host cells. Optimization of the 4‐anilino group and the 6,7‐quinoline substituents produced GAK inhibitors with nanomolar activity, over 50 000‐fold selectivity relative to other members of the numb‐associated kinase (NAK) subfamily, and a compound (6,7‐dimethoxy‐N‐(3,4,5‐trimethoxyphenyl)quinolin‐4‐amine; 49 ) with a narrow‐spectrum kinome profile. These compounds may be useful tools to explore the therapeutic potential of GAK in prevention of a broad range of infectious and systemic diseases. 相似文献