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401.
Drug testing programs in the United States may broadly be classified as mandatory (such as under DOT or Nuclear Regulatory Commission regulation) or nonmandatory. In the first group, a regulated employer is required by federal regulations to test. In the second, the employer chooses to test for reasons other than the federal requirements. It always was intended that the federal program would be the model for testing by private employers, and that mandatory testing would be extended to private employers who are regulated by various agencies of the federal government. This has happened. In addition, private employers who are not required to test under federal authority have instituted employee drug testing programs closely modeled on the federal program. Whether mandated or not, a well-designed and implemented drug testing program is a valuable tool in the effort to fight drugs in the workplace. 相似文献
402.
Subramaniam Sathivel & Peter J. Bechtel 《International Journal of Food Science & Technology》2006,41(5):520-529
Soluble protein powders were produced from pollock by‐products and evaluated for their functional, nutritional and rheological properties. Soluble protein powders were made from pollock viscera (PVSP), viscera without liver (PVWLSP), heads (PHSP), frames (PFSP), trimmings (PTSP), and liver (PLSP) and had protein contents ranging from 65.0% to 78.9%. Yield of PVWLSP was higher than that of other pollock proteins powder and PTSP had the highest nitrogen solubility value (85.7%). Emulsion capacity and emulsion stability of the pollock protein powders ranged from 29% to 34.5% (mL of oil per 200 mg of protein) and 65.3% to 77.6%, respectively. Highest and lowest fat adsorption values were observed for PFSP (10.6 mL of oil per gram of protein) and PVSP (4.1 mL of oil per gram of protein), respectively. Fish protein powder samples were good sources in K, P, and Mg and amino acids. Emulsions made with pollock soluble protein powders exhibited viscoelastic characteristics. 相似文献
403.
Kinetics of homogeneous 5‐hydroxymethylfurfural oxidation to 2,5‐furandicarboxylic acid with Co/Mn/Br catalyst
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Xiaobin Zuo Amit S. Chaudhari Kirk Snavely Fenghui Niu Hongda Zhu Kevin J. Martin Bala Subramaniam 《American Institute of Chemical Engineers》2017,63(1):162-171
2,5‐furandicarboxylic acid (FDCA) is a potential non‐phthalate based bio‐renewable substitute for terephthalic acid‐based plastics. Herein, we present an investigation of the oxidation rate of 5‐hydroxymethylfurfural (HMF) to FDCA in acetic acid medium using Co/Mn/Br catalyst. Transient concentration profiles of the reactant (HMF), intermediates [2,5‐diformylfuran (DFF), 5‐formyl‐2‐furancarboxylic acid (FFCA)], and the desired product (FDCA) were obtained for this relatively fast reaction in a stirred semi‐batch reactor using rapid in‐line sampling. Comparison of the effective rate constants for the series oxidation steps with predicted gas–liquid mass transfer coefficients reveals that except for the FFCA → FDCA step, the first two oxidation steps are subject to gas–liquid mass transfer limitations even at high stirrer speeds. Novel reactor configurations, such as a reactor in which the reaction mixture is dispersed as fine droplets into a gas phase containing oxygen, are required to overcome oxygen starvation in the liquid phase and further intensify FDCA production. © 2016 American Institute of Chemical Engineers AIChE J, 63: 162–171, 2017 相似文献
404.
Zulhadi Iskandar Radzi Mohd Zieauddin Kufian Vengadaesvaran Balakrishan Adarsh Kumar Pandey Zul Hazrin Zainal Abidin Siti Rohani Sheikh Raihan Nasrudin Abd Rahim Ramesh Subramaniam 《International Journal of Applied Ceramic Technology》2022,19(4):2036-2052
Spinel lithium manganese oxide, LiMn2O4 coated with V2O5 layer (labeled as LMO-VO) has been developed and its electrochemical performances as cathode material for lithium-ion batteries has been evaluated at high cut-off voltage (>4.5 V vs. Li/Li+) and compared with pristine LiMn2O4 (labeled as LMO). The crystal structure investigations show that LMO-VO has longer Li–O bond length for fast Li-ion diffusion kinetic process. The scanning electron microscopy results indicate that LMO-VO has finer particles and the V2O5 layer has been successfully coated on the LMO surface uniformly. The highly conductive V2O5 coating layer enhances the ionic conductivity of the LMO cathode, as evidenced by the significant drop of Rct value from the Nyquist plot. Under high operating voltage, the cell employed with coated LMO shows exceptional cycling performance in capacity retention and potential difference. After 300 cycles, the capacity retention per cycle has been boosted from 99.90% to 99.94% by adopting the V2O5 coating layer. In addition, surface coating with V2O5 stabilizes the potential difference at very minimal change for a longer period. This convincingly proves that the V2O5 coating layer not only protects against hydrofluoric acid (HF) attack and greatly restrains the increase of cell polarization at high voltage. 相似文献
405.
In this paper, bio-diesel was prepared from watermelon seed oil by using transesterification processes. The performance, emission and combustion characteristics of the various bio-diesel and diesel blends (B20–B80 and B100) are compared with those of the diesel. The experimental result indicates that owing to a lower heating value of bio-diesel, the brake-specific fuel consumption increased and the brake thermal efficiency decreased. However, bio-diesel and its blends reduced carbon monoxide and hydrocarbon, while the oxides of nitrogen and smoke slightly increased. The combustion analysis proved that increasing bio-diesel blend ratio decreases the cylinder pressure and heat release rate when compared with base diesel. 相似文献
406.
Huaixia Yin Jianing Pu Yuting Wan Bob Xiang Peter J. Bechtel Subramaniam Sathivel 《Journal of food science》2010,75(1):E11-E17
ABSTRACT: Catfish skin is an abundant and underutilized resource that can be used as a unique protein source to make fish skin protein hydrolysates. The objectives of this study were to isolate soluble and insoluble proteins from hydrolyzed catfish skin, study the rheological and functional properties of the protein hydrolysates, and evaluate the properties of emulsions made from the protein powders. Freeze-dried catfish skin soluble (CSSH) and insoluble hydrolysate (CSISH) powders were analyzed for proximate analysis, emulsion stability, fat absorption, amino acids, color, and rheological properties. CSSH had significantly ( P < 0.05) higher protein, ash, and moisture content but lower fat content than that of CSISH. The yield of CSSH (21.5%± 2.2%) was higher than that of CSISH (3%± 0.3%). CSISH had higher emulsion stability than CSSH. CSSH was light yellow in color and CSISH was darker. The mean flow index values for emulsion containing CSSH (ECSSH) and CSISH (ECSISH) were both less than 1, indicating that they were both pseudoplastic fluid. The G ' and G " values for the ECSISH were higher than that of ECSSH, indicating that the viscoelastic characteristic of the emulsion containing CSISH was greater than that of the emulsion containing CSSH. The study demonstrated the CSSH and CSISH had good functional and rheological properties. They have potential uses as functional food ingredients. 相似文献
407.
十溴二苯醚(decaBDE)是一种高效、通用的阻燃剂,几十年来被广泛地应用于电子、电线和电缆、保温、纺织、交通及其他领域。但是,由于欧洲和美国对其使用施加了种种限制,再加上美国主要制造商主动停止生产和销售这种产 相似文献
408.
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410.
PURPOSE: To compare conjunctival epithelium expression of HLA-DR and ICAM-1 with tear dynamics and ocular surface parameters. METHODS: Brush cytology and flow cytometry were used to quantitatively analyze HLA-DR and ICAM-1 expression in 28 dry eye patients. RESULTS: HLA-DR was expressed in 66% of the conjunctival cells of dry eye patients. This expression correlates with that of ICAM-1, as well as with the Schirmer test results (p < 0.05). CONCLUSION: This study confirmed that dry eye consists not only of ocular surface desiccation, but also of upregulation of the HLA-DR and ICAM-1 molecule in the conjunctival epithelium, possibly resulting in increased inflammation. 相似文献