Advanced manufacturing technology use: Exploring the effect of the nationality variable

A few studies (Jaikumar 1986) have left an impression among researchers that Japanese manufacturers use more advanced manufacturing technologies (AMTs) then their US counterparts. Presuming this were to be true, we hypothesized that nationality of the firm is an important factor in AMT use. To test the effect of the nationality variable on AMT use we compared the use of 18 AMTs in the US and Japan in an exploratory study using data from 160 US firms and 125 Japanese firms.There is clear evidence that the nationality of the firm is a factor in AMT use; that is AMT use is significantly different in the two countries. One explanation for the differences in AMT use may lie in the respective strategic orientations of the manufacturers in the two countries. A major finding in this study is that, while US manufacturers use more scheduling and control technologies, their Japanese counterparts use more factory floor technologies. Several hypothesis are offered as propositions for future research.     

The nature of the C18 polyethenoic fatty acids of butter fat

Methyl C₁₈ polyenoate concentrates were prepared from two samples of butter fat by low temperature crystallization and fractional distillation. The concentrates were fractionated on a silicic acid column and the resulting fractions were analyzed by ultraviolet and infrared spectrophotometric methods. About 42 and 30% repectively, of the non-conjugated dienoate in the two samples were shown to have thecis,trans configuration. Fractions rich in dienoate and trienoate were prepared from the C₁₈ polyene concentrates by silicic acid chromatography and the nature of these acids was studied by bromination, lipoxidase enzyme methods, and by alkali isomerization for varying periods of time. About 65 and 73%, respectively, of the non-conjugated dienoate in the two samples investigated were found to consist of linoleic acid while 79 and 71% of the trienoate were linolenic acid. Linoleic and linolenic acids were identified by preparing the characteristic tetra- and hexabromostearic acids. Atrans,trans isomer of linoleic acid does not seem to be present in butter fat. A major proportion of the non-conjugated dienoic acid other than linoleic acid was found to have widely separated double bonds withcis,trans configuration. Occurrences of a C₁₅ saturated acid, a branchedchain C₁₇ saturated acid, and a heptadecenoic acid were indicated by gas chromatography. From a dissertation submitted by K. Sambasivarao to the Ohio State University in partial fulfillment of the requirements for the Ph.D. degree, June, 1960. This work was supported in part by a grant from the Ohio State University Development Fund to the Institute of Nutrition and Food Technology and by several teaching assistantships from the Department of Physiological Chemistry.     

Selective hydrogenation with copper catalysts: I. Isolation and identification of isomers formed during hydrogenation of linolenate

Methyl linolenate was hydrogenated with 10% copper chromite catalyst at 150 C and atmospheric hydrogen pressure. The product was separated into monoene, diene and triene fractions by countercurrent distribution. These fractions were further separated into various geometrical isomers. The double bond location in the various fractions was determined by reductive ozonolysis. Double bonds in bothcis andtrans monoene fractions, as well as incis,trans andtrans,trans conjugated dienes, were extensively isomerized. A monoene containing vinylic unsaturation was one of the major products. The nonconjugated dienes were mostly dienes whose double bonds were widely separated. Results are explained on the basis of conjugation of the double bonds in linolenate followed by hydrogen addition. Presented in part at the symposium “Hydrogenation Process,” Division of Industrial Engineering Chemistry, 157th American Chemical Society Meeting, Minneapolis, April 1968. No. Utiliz. Res. Dev. Div., ARS, USDA.     

Hydrogenation of unsaturated fatty esters with copper-chromite catalyst: Kinetics,mechanism and isomerization

Hydrogenation of linolenate with copper chromite produced a large amount of conjugated diene and minor amounts of nonconjugatable dienes. The double bonds in conjugated dienes and monoenes were scrambled all along the chain. This product distribution can be explained if it is assumed that conjugation of the double bonds is followed by hydrogenation. In competitive hydrogenation, fatty esters with conjugated double bonds were reduced preferentially over fatty esters with methylene-interrupted double bonds. Isomerization of conjugated double bonds (geometric and positional) occurred more rapidly than reduction. Reduction of conjugated double bonds in the presence of deuterium resulted in a majority of the products containing no deuterium. Most of the added deuterium was incorporated into the unreacted material. Mechanisms are proposed to account for the products formed during the hydrogenation of linolenate, linoleate and their isomers. One of 10 papers to be published from the Symposium “Hydrogenation,” presented at the AOCS Meeting, New Orleans, April 1970. No. Utiliz. Res. Dev. Div., ARS, USDA.     

The use of pulsed laser deposition to produce low-temperature barium titanate films on nickel tape and carbon fiber fabric

In order to explore the functionalization of wearable fabrics for power generation, barium titanate (BTO) was deposited on nickel tape and on carbon fiber fabric employing pulsed laser deposition (PLD) methods under conditions normally not considered ideal to produce optimum ferroelectric properties, namely, at temperatures as low as 100°C and under various oxygen partial pressures. The remnant charge polarization and film resistance properties were evaluated to determine the effect of the aforementioned deposition conditions. The P–V characterization indicates that the BTO films still retained ferroelectric properties down to 200°C, below which, the behavior was only paraelectric. Piezoelectric measurements were made with a resulting potential of 4 kV/m.     

Hall and ion-slip effects on MHD natural convective flow past an unbounded vertical porous channel with thermodiffusion

The consequences of Soret in addition to Dufour of natural convection heat and mass transfer for the unsteady three-dimensional boundary layer flow through a perpendicular condition of the existence of viscous dissipation, invariable suction, Hall as well as ion slip consequences into relation. The prevailing partial differential equation is dissolved digitally utilizing the implicit Crank–Nicolson finite difference method. The velocity, temperature, as well as concentration dispensations, is addressed computationally and demonstrated by the graphs. Numerical values of the Nusselt number, skin friction as well as Sherwoods numbers nearby the plate are discussed for a choice of values of substantial parameters and are displayed in a tabular manner. It is noticed that the temperature of the fluid diminishes with higher Prandtl numbers. The resulting velocity diminishes with the growing Hartmann number. Rotation, Soret, and Dufour parameters strengthen the velocity and momentum boundary layer thickness. The velocity intensifies through growing Hall and ion-slip parameters and the revoke trend is acquired with enhancement in suction parameter.     

Functionalized polymer networks: synthesis of microporous polymers by frontal polymerization

A series of glycidyl methacrylate (GMA)-ethylene dimethacrylate (EGDM) copolymers of varying compositions were synthesized by free-radically triggered thermal frontal polymerization (FP) as well as by suspension polymerization (SP) using azobisisobutyronitrile [AIBN] as initiator. The two sets of copolymers were characterized by IR spectroscopy and mercury intrusion porosimetry, for determination of epoxy number and specific surface area. Frontal polymerization was more efficient, yielding greater conversions at much shorter reaction times. The self-propagating frontal polymerization also generates microporous material with narrow pore size distribution. It yields higher internal pore volume and surface area than suspension polymerization, surface morphologies are, however, inferior.     

Newtonian heating effect on laminar flow of Casson fluids: Thermal analysis

In the present study, free convective, laminar flow of Casson fluid is investigated numerically over a nonlinear stretched sheet to observe the characteristics of heat transfer in the presence of Newtonian heating. Nonlinear differential equations are derived from the present flow by utilizing the appropriate transformations. Thereafter, for the linear stretching case, an exact solution is applied for the momentum equation, and for the nonlinear stretching case, a convergent numerical technique, SRM, is applied. Computations of SRM and exact solutions are displayed through graphs. For various physical parameters, variation in velocity profile is observed by means of numerical computations and presented graphically. For checking the accuracy and convergence of the proposed method, outcomes are validated with the available outcomes in the literature and compared. The outcomes demonstrate that the velocity profile is reduced for the nonlinear stretching parameter effect, and, with increasing $\mathit{Pr}$, the temperature is decreased and there is a reduction in the thickness of the thermal boundary layer.     

Improved mechanical properties of acrylic bone cement with short titanium fiber reinforcement

Acrylic bone cements are widely used in total joint arthroplasties to grout the prosthesis to bone. The changes in the tensile properties and fracture toughness of polymethylmethacrylate (PMMA) bone cements obtained by the addition of control and heat treated short titanium fibers are studied. Heat treatment of titanium fibers is conducted to precipitate titania particles on the fiber surface to improve the biocompatibility of the metal. Control and heat treated short titanium fibers (250 μ long and 20 μ diameter) were used as reinforcements at 3 volume %. X-ray diffraction indicated the presence of a rutile form of titania due to the heat treatments. The tensile and fracture properties were improved by the addition of fibers. Bone cements reinforced with titanium fibers heated at 550^∘C for 1 h followed by 800^∘C for 30 minutes show the largest increase in fracture toughness along with the smallest changes in elastic modulus and needs to be further investigated.