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101.
Towards an Environmentally Acceptable Heterogeneous Catalytic Method of Producing Adipic Acid by the Oxidation of Hydrocarbons in Air 总被引:1,自引:0,他引:1
Raja Robert Lee Sang-Ok Sanchez-Sanchez Manuel Sankar Gopinathan Harris Kenneth D.M. Johnson Brian F.G. Thomas John Meurig 《Topics in Catalysis》2002,20(1-4):85-88
A survey is given of the catalytic methods potentially available for the production of adipic acid by the oxidation of readily available hydrocarbon precursors under environmentally benign conditions. Encouraging results are reported using H2O2 as oxidant and microporous FeAlPO-5 as catalyst at moderate temperatures. 相似文献
102.
103.
H. M. Teeter L. C. Dorman L. Harris 《Journal of the American Oil Chemists' Society》1960,37(11):552-555
The molecular-weight distributions of several conjugated soybean vinyl ether homopolymers were studied by means of the integral
fractionation technique. Polymers having number average molecular weights of 2,200, 4,800 and 10,000 prepared with stannic
chloride as catalyst as well as a polymer having a molecular weight of 3,400 prepared with boron trifluoride as catalyst were
included in the study. The observed distributions for all the polymers were found to approximate the socalled “most probable”
distributions expected theoretically for polymers obtained by simple difunctional polymerization.
Presented at annual meeting. American Oil Chemists' Society, New Orleans, La., April 20–22, 1959.
This is a laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, U. S. Department
of Agriculture. 相似文献
104.
An axisymmetric model for thread forming in polycarbonate and polypropylene screw and boss fasteners
Plastic boss and screw fasteners are an economical means of securing automotive components, such as instrument or body panels. However, new materials and/or suboptimal design present challenges to the boss/screw effectiveness. Failure of a boss/screw can result is loss of functional performance or increased squeak and rattle. Failure is often controlled by what occurs during the initial thread‐forming process. Thus, the goal of this paper is to develop an FEA model to elucidate the thread‐forming process so that we can facilitate subsequent design and/or process optimization, and understand potential failure modes. The FEA must accommodate nonlinear couplings, such as large strain and heat transfer. Heat generation is present in the forms of interfacial shear heating and plastic work associated with the large deformation of the interface between the boss and screw. Strain rate‐dependent materials are included using the Eyring theory for plastic flow of polymeric materials. Results of the model are presented and compared to experimentally determined torque curves and temperatures. Polym. Eng. Sci. 44:1498–1508, 2004. © 2004 Society of Plastics Engineers. 相似文献
105.
M. A. Zeitoun W. B. Harris W. D. Harris 《Journal of the American Oil Chemists' Society》1963,40(7):279-283
In this investigation the application of gaseous ammonia to cottonseed oil refining was explored. The ammonia reacted quantitatively
with the free fatty acids in the oil; its solubility in coftonseed oil was determined as a function of pressure. In “degumming”
it was more efficient in removing phosphatides than other agents.
A reduction in refining loss resulted for oils refined with gaseous ammonia as outlined and compared with the standard AOCS
cup loss analysis. However, the oil colors were substantially higher even though the ammonia treated oils were re-refined
with caustic solution. Results using cottonseed oil-hexane “miscellas” containing less than 70% oil showed low refining losses,
but the colors were estremely high. Above 70% oil content the losses were higher, but the colors were lower. The colors never
equalled “standard cup” results.
This study was sponsored by the Texas Engineering Experiment Station and the Cotton Research Committee of Texas. 相似文献
106.
In this paper, we present an invariant‐set‐based method for actuator and sensor fault detection and isolation in Lure systems. The Lure plant is controlled by an observer‐based feedback tracking controller, designed for the nominal (fault‐free) system. Suitable residual signals are constructed from measurable system outputs and estimates associated with the nominal observer. Faults are diagnosed by online contrasting the residual signal trajectories against sets of values that the residuals are shown to attain under healthy or faulty operation. These values are obtained via set‐invariance analysis of the system closed‐loop trajectories. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
107.
J. C. Harris R. M. Anderson J. Satanek 《Journal of the American Oil Chemists' Society》1961,38(3):123-127
Previous papers have reported radiotagged fatty soil removal from glass either by solvents or by aqueous solutions of sodium
tripolyphosphate and other builders. This paper provies soil-removal data for aqueous systems of both pure and built surfactant
compositions of the nonionic and alkylbenzene sulfonate types. In general, nonionics are the most effective detergents for
the system fatty soil/glass; the 10-mole ethylene oxide adduct products show peak soil-removal. Nonionic surfactants appear
most effective for soil removal when used in baths closely approaching their cloud-points. Though modification of hydrophobe
by EO addition can affect cloud point, peak soil-removal effectiveness seems to be controlled by hydrophobe selection. Highest
soil removal for the alkylbenzene series occurred with the longer alkyl chain (pentadecyl).
Admixture of surfactant and sodium tripolyphosphate provided synergistic compositions with certain 10-EO surfactants. Building
of anionics markedly improved soil removal over the pure material but seldom exceeded the removal by STP alone.
Presented at 34th fall meeting, American Oil Chemists' Society, New York, October 17–19, 1960. 相似文献
108.
Richard H. Harris Vicki J. Boyd Graham J. Hutchings Stuart H. Taylor 《Catalysis Letters》2002,78(1-4):369-372
The effect of water addition on the complete oxidation of benzene and propane VOCs by uranium oxide catalysts has been investigated. Benzene oxidation was studied using a silica supported U3O8 catalyst. Complete oxidation is promoted by the addition of 2.6% water compared with the reactivity when no water is added to the reactant feed. Increasing the water concentration to 12.1% resulted in a suppression of oxidation activity. Investigation of propane oxidation using U3O8 shows a dramatic promotion of activity. Propane conversion was ca. 50% at 600 °C without added water, whilst it increased to 100% at 400 °C with the addition of 2.6% water. A comparison of oxidation activity has been made with Mn2O3, an oxide recognised for complete oxidation. In contrast to the U3O8 catalysts the addition of 2.6% water suppresses the activity of Mn2O3. In situ powder X-ray diffraction studies showed that the bulk U3O8 structure was stable under all the reaction conditions. The origin of the increased activity is not clear but may be due to modification of the catalyst surface and the contribution from new reaction pathways such as steam reforming. 相似文献
109.
Poly(ethylene ether carbonate) polyols can be modified by chemical reactions with polyglycol modifiers under conditions of elevated temperatures and reduced pressures. The modifier becomes chemically incorporated into the modified polyol and is used to control properties such as moisture sensitivity, CO2 content, Tg, density, etc. in the resultant polyol. However, glycerol cannot be used as a modifier for poly(ethylene ether carbonate) polyols under the same conditions since it reacts with poly(ethylene ether carbonate) polyols by a transesterification reaction sequence to form glyceryl carbonate. As the temperature is increased, the glyceryl carbonate decomposes to yield glycidol and carbon dioxide. These reactions are conveniently followed by 13C-NMR. The preparation of glyceryl carbonate by this process has not been previously reported. 相似文献
110.
Takashi Kashiwagi Alexander B. Morgan Joseph M. Antonucci Mark R. VanLandingham Richard H. Harris Walid H. Awad John R. Shields 《应用聚合物科学杂志》2003,89(8):2072-2078
PMMA, poly(metheylmethacrylate), nanocomposites were made by in situ radical polymerization of MMA, methylmethacrylate, with colloidal silica (ca. 12 nm) to study the effects of nanoscale silica particles on the physical properties and flammability properties of PMMA. Transparent samples resulted and the dispersity of the particles was examined by transmission electron microscopy and atomic force microscopy. The addition of nanosilica particles (13% by mass) did not significantly change the thermal stability, but it made a small improvement in modulus, and it reduced the peak heat release rate roughly 50%. Last, the flame‐retardant mechanism provided by the addition of nanosilica particles in PMMA is discussed. Published 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2072–2078, 2003 相似文献