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91.
92.
A study has been made of the cathodic deposition of copper ions from flowing dilute aqueous solutions onto a packed bed of graphite. The electrodeposition reaction is mass transfer controlled and expressions are presented for the cathodic current as a function of time, solution flow rate and bed characteristics. These have been verified from potentiostatic experiments. The cathode current efficiency is shown to approach 100% and packed bed electrodes are shown to be an effective means of extracting or removing metal ions from dilute solutions. 相似文献
93.
The activities of several commercial nickel catalysts were determined by measuring their activation energies. Among these
catalysts, G95E, Resan 22, Nysosel 222 and 325, all with low activation energy, were more active than DM3 and G95H, which
had higher activation energy. However, the less active catalysts increased the linoleate selectivity of soybean oil during
hydrogenation. The yields of bothtrans isomers and winterized oil were higher for the more selectively hydrogenated oil catalyzed by the less active catalysts.
In the sensory evaluation, the fractionated solid fat that contained moretrans isomers was lower in flavor scores than the fractionated liquid oil after hydrogenation and winterization of soybean oil. 相似文献
94.
Computing scattering rates of electrons and phonons stands at the core of studies of electron transport properties. In the high field regime, the interactions between all electron bands with all phonon bands need to be considered. This full band interaction implies a huge computational burden in calculating scattering rates. In this study, a new accelerated algorithm is presented for this task, which speeds up the computation by two orders of magnitude (100 times) and dramatically simplifies the coding. At the same time, it visually demonstrates the physical process of scattering more clearly. 相似文献
95.
Benjamin D. Deacon A. Cecil Wamble 《Journal of the American Oil Chemists' Society》1954,31(7):284-287
Conclusions A procedure for the analysis of cottonseed and its products for Vitamin E has been developed and improved. The present procedure
generally gives good checks on duplicate analyses.
The Vitamin E content of whole cottonseed is somewhat more a function of variety than of locality. The 1952 crop of cottonseed
contained more Vitamin E than the 1951 crop. The two crops averaged 84 g. per ton and 68.5 g. per ton, respectively.
Most recent results show that there is no loss of Vitamin E in the storage of cottonseed or during the processing of the seed
for its oil and other products.
The hexane-soluble portion of a methanol extract of rolled or cooked cottonseed meats contains Vitamin E in concentrations
that have exceeded the values reported for wheat germ oil, the present commercial source.
A sample of commercial solvent extracted cottonseed meal was found to contain considerably less Vitamin E than hydraulic-
or screw-pressed meals.
The Vitamin E research described in this writing was conducted as a cooperative project of the Texas Engineering Experiment
Station and the Cotton Research Committee of Texas. 相似文献
96.
相位测量定位法在焦炉车辆上的应用与研究 总被引:3,自引:1,他引:3
文中通过测量载波相位进行定位的方法来解决焦炉车辆的定位问题,以达到无线定位的目的。并对定位的数学模型进行了详细的分析与论述。 相似文献
97.
Richard Kotek Dong‐Wook Jung Joon Ho Kim Brent Smith Patricia Guzman Benjamin Schmidt 《应用聚合物科学杂志》2004,92(3):1724-1730
The surface alkaline hydrolysis of fibers made from poly(trimethylene terephthalate) (PTT) was studied after extruding the polymer at high spinning speeds from 2000 to 6000 m/min and heat setting in the range of temperatures from 100 to 180°C. Fiber weight loss increased with an increasing heat‐setting temperature but it was also dependent on the spinning speed. Some of the partially hydrolyzed fibers had a well‐developed, hydrophilic surface, and pore size in the range of 0.69 to 1.20 μm. The optimum reaction and morphological conditions for increasing porosity in PTT fibers depends on spinning speed and heat‐setting temperature. A temperature of 180°C is the upper limit for heat‐setting PTT filaments but seems to be the most effective for making porous fibers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1724–1730, 2004 相似文献
98.
Tristan Allard Benjamin Nguyen Philippe Pucheral 《Distributed and Parallel Databases》2014,32(2):191-244
The goal of Privacy-Preserving Data Publishing (PPDP) is to generate a sanitized (i.e. harmless) view of sensitive personal data (e.g. a health survey), to be released to some agencies or simply the public. However, traditional PPDP practices all make the assumption that the process is run on a trusted central server. In this article, we argue that the trust assumption on the central server is far too strong. We propose Met ??P, a generic fully distributed protocol, to execute various forms of PPDP algorithms on an asymmetric architecture composed of low power secure devices and a powerful but untrusted infrastructure. We show that this protocol is both correct and secure against honest-but-curious or malicious adversaries. Finally, we provide an experimental validation showing that this protocol can support PPDP processes scaling up to nation-wide surveys. 相似文献
99.
Recent studies of self-condensation and co-condensation of melamine-formaldehyde resins; cure at low temperatures 总被引:1,自引:0,他引:1
Self-condensation: recent research on the chemical pathways by which alcoholated melamine-formaldehyde (MF) resins react with themselves and on the product structures is summarized. Model compound studies suggest that
bridges are less stable than widely thought unless they are in hexahydro-1,3,5-triazine ring structures. In acyclic structures they are probably less stable than
bridges. Co-condensation: studies of how the composition of MF resins influences the rates of reaction with poly(ol) co-reactant show that MF resins that contain very low levels of
and/or
functionality are quite reactive. Reactivities of a variety of poly(ester) and acrylic coreactants were studied. By combining reactive MF resins with reactive co-reactants one can formulate high solids enamels that cure by co-condensation in 30 min at 50 to 65 °C with 0.5 parts per hundred (phr) of p-toluenesulfonic acid (p-TSA) catalyst. Cure at 25 °C appears feasible with higher catalyst levels. 相似文献
100.
Abstract. We study an iterative filtering method to estimate frequencies of random Gaussian sinusoids in white noise. The method uses higher order crossings and takes advantage of a fixed point to guide the use of bandpass filtering in an attempt effectively to increase the signal-to-noise ratio. At each iteration the expected zero-crossing rate is estimated from independent time series. Convergence occurs with any prespecified probability less than one. 相似文献