Showing papers by "National Tsing Hua University published in 1984"
TL;DR: In this article, the authors determined catalytic activity for nonoxidative dehydrogenation of ethylbenzene using calcined catalysts at temperatures between 550 and 1000 °C.
104 citations
TL;DR: This note shows that the problem of finding a fully polynomial approximation algorithm for multidimensional knapsack problems is NP-hard.
Abstract: Polynomial and fully polynomial approximation algorithms for single-dimensional knapsack problems have been extensively studied and a number of such algorithms constructed. This note shows that the problem of finding a fully polynomial approximation algorithm for multidimensional knapsack problems is NP-hard.
80 citations
TL;DR: In this paper, low-temperature specific heat, electrical resistivity, ac magnetic susceptibility, and dc magnetization measurements were made on ternary cerium and uranium transition metal borides with the general formula CeT3B2 (T=Co, Ru, Rh, and Ir) and UT3B 2 (T = Co, Ru and Ir).
Abstract: Low-temperature specific heat, electrical resistivity, ac magnetic susceptibility, and dc magnetization measurements were made on ternary cerium and uranium transition metal borides with the general formula CeT3B2 (T=Co, Ru, Rh, and Ir) and UT3B2 (T=Co, Ru, and Ir). The compound CeRu3B2 was found to exhibit superconductivity below 0.68 K. The values of the electronic specific heat coefficient range from 9.7 mJ/mole-K2 for CeCo3B2 to 64 mJ/mole-K2 for UIr3B2. The electrical resistivity versus temperature curves of all of the compounds exhibit negative curvature and are reminiscent of valence fluctuation behavior. In the case of CeIr3B2, the electrical resistivity attains a maximum value at 180 K, while the dc magnetic susceptibility has a temperature dependence that is typical of intermediate valence Ce compounds, approaching a finite value at zero temperature. The electrical resistivity of the ferromagnetic compound CeRh3B2 reveals a rapid decrease in spin disorder resistivity below 120 K. The dc magnetic susceptibility of this material can be described as the sum of a constant term and a Curie-Weiss contribution with an effective magnetic moment of 1.01 µB per formula unit and a Curie-Weiss temperature of 119 K. Magnetization measurements on CeRh3B2 yield a saturation magnetic moment of 0.37 µB per formula unit and a Curie temperature of 113 K.
44 citations
TL;DR: In this paper, the temperature programmed desorption of NH4-ZSM-5, Na, TPA-ZM-5 and ammonia on silicalite zeolites was investigated using thermoconductivity, on-line mass spectrometry automatic pH titration.
43 citations
TL;DR: In this article, the comparative abilities and limitations of humans and computers in the operation and control of flexible manufacturing systems (FMS) are reviewed and a table emphasizing the allocation of functions between humans and computer in an FMS is produced.
Abstract: The comparative abilities and limitations of humans and computers in the operation and control of flexible manufacturing systems (FMS) are reviewed and a table emphasizing the allocation of functions between humans and computers in an FMS is produced. A case study is presented to illustrate the effectiveness of the allocation of functions.
41 citations
TL;DR: Tryptophan modification with 2-hydroxy-5-nitrobenzyl bromide suggests that the Trp residues in phospholipase A2 enzymes and presynaptically acting neurotoxins are involved in substrate binding.
Abstract: Three phospholipases A2 purified from cobra venoms and two presynaptically acting neurotoxins that exhibit phospholipase A2 activity were subjected to tryptophan modification with 2-hydroxy-5-nitrobenzyl bromide. Associated with the modification of an increasing number of Trp residues were marked decreases in enzymatic activity and lethality, whereas antigenicity remained unchanged. The degree of exposure of tryptophanyl groups as determined by acrylamide quenching was consistent with the relative reactivity toward 2-hydroxy-5-nitrobenzyl bromide, except for Hemachatushaemachatus phospholipase A2, which showed unusually high reactivity due to its characteristic dimeric conformation. Difference spectra of Trp-modified derivatives differed from those of their native enzymes by the presence of a new positive perturbation between 350 and 500 nm, with a maximum at 415 nm. Scatchard plots revealed only one type of binding site for Ca2+, and the binding abilities of the modified enzymes were not impaired. At pH 8.0, all native enzymes enhanced the emission intensity of 8-anilinonaphthalene sulfonate (ANS) dramatically, and the emission intensity of the ANS-enzyme complex increased or decreased in parallel with increasing concentration of Ca2+ for the respective enzyme. The Trp-modified derivatives did not enhance the emission intensity of ANS at all either in the presence or absence of Ca2+. By means of tryptophan modification, we were able to infer that the tryptophan residues are in the vicinity of the Ca2+ binding site and are directly involved in the binding with ANS. This, together with the suggestion that the hydrophobic pocket that interacts with ANS might be the site of binding of the phospholipase A2 enzyme with the substrate, suggests that the Trp residues in phospholipase A2 enzymes and presynaptic toxins are involved in substrate binding.
39 citations
TL;DR: In this article, a variational-perturbative method is used to calculate the binding energy of an exciton in quantum well structure of AlxGa1-xAs-GaAs-AlxGa 1-xA.
38 citations
TL;DR: In this paper, the authors describe the use of THM in the growth of CuInS 2 single crystals, and demonstrate the feasibility of growing large single crystals of certain I-III-VI 2 compounds.
35 citations
TL;DR: A microprocessor-based incremental servo system with a variable structure implemented with an Intel 8085 microprocessor to control a dc motor, and fast response without overshoot and good steady-state accuracy can be easily obtained.
Abstract: A microprocessor-based incremental servo system with a variable structure is presented. It is implemented with an Intel 8085 microprocessor to control a dc motor, and fast response without overshoot and good steady-state accuracy can be easily obtained. The design procedure is described in detail. Also, the comparison with a conventional fixed structure system is given.
31 citations
TL;DR: In this paper, the Cook-de-Fontaine theory for the free energy of solid solutions has been evaluated for Au-40 at 1023 K above the miscibility gap, by combining results from neutron inelastic and X-ray diffuse scattering from the same single crystal.
31 citations
TL;DR: Based on Kirchhoff's hypothesis and relevant variational principles, the authors presented an assumed hybrid-displacement finite element model to solve the bending problems of thin cracked plates subjected to static and dynamic loadings.
Abstract: Based on Kirchhoff's hypothesis and relevant variational principles, this work presents an assumed hybrid-dis-placement finite element model to solve the bending problems of thin cracked plates subjected to static and dynamic loadings. To provide a potential method of non-destructive testing in evaluating the integrity of structure, natural vibrations of the thin cracked plate are also studied. Since the integrand of the associated functional contains the second-order derivatives of the lateral displacement of the plate, the compatibility requirements for the lateral displacement and its normal slope at inter-element boundaries are enforced in an integral sense through the use of a Lagrangian multiplier technique. The proper singular behaviours for the bending stresses and strains are incorporated in the singular elements around the crack-tips. The static and dynamic symmetric and anti-symmetric bending stress intensity factors can be directly computed. To avoid underestimation of dynamic bending stress intensity factors, the important role of the singular elements is also demonstrated. Good correlations between the computed results and available solutions in the literature show the accuracy and efficiency of the present work. Some new solutions for the bending thin cracked plates are then drawn.
TL;DR: In this paper, the anodic polarization phenomenon in a Ti/Fe flow battery was studied and a small amount of Pd (0.02 wt.%) was added to the inert graphite electrode in the Ti half cell to reduce the discharge overpotential by about 50%.
TL;DR: It is concluded that changes in isoelectric points are not responsible for altered lethal potencies following chemical modification and that some pharmacological effects of snake venom phospholipases A2 are due to a non-enzymatic action, suggesting two distinct but perhaps overlapping active sites.
TL;DR: Two formulas are derived for the average number of buckets to be examined over all possible partial match queries for Cartesian product files and random files, respectively.
Abstract: In this paper, we shall derive two formulas for the average number of buckets to be examined over all possible partial match queries for Cartesian product files and random files, respectively. The superiority of the Cartesian product file is established. A new multi-key file, called a partition file, is introduced. It is shown that both Cartesian product files and random files are special cases of partition files.
TL;DR: A theoretical analysis shows that the probability of the occurrence of this worst case is extremely small, and the worst case performance of this algorithm is stated.
Abstract: In this paper a parallel algorithm to solve the stable marriage problem is given. The worst case performance of this algorithm is stated. A theoretical analysis shows that the probability of the occurrence of this worst case is extremely small. For instance, if there are sixteen men and sixteen women involved, then the probability that the worst case occurs is only 10−45. Possible future research is also discussed in this paper.
TL;DR: It is shown that on the average, the total length of a Delaunay triangulation is of the same order as that of a minimum triangulating, under the assumption that the authors' points are drawn from a homogeneous planar Poisson point distribution.
Abstract: We shall show that on the average, the total length of a Delaunay triangulation is of the same order as that of a minimum triangulation, under the assumption that our points are drawn from a homogeneous planar Poisson point distribution.
TL;DR: In this article, an effective method for solving either the stretched functional ordinary differential equation describing a crystallization process using breakage models, or the partial differential equations for a population balance which represent the transient crystallisation process was proposed.
TL;DR: In this paper, five mechanistic models dealing with solute removal rate in liquid membranes, as they appear in the literature, are critically reviewed and discussed and compared against the experimental data of Ho et al.
TL;DR: Etude theorique des caracteristiques de l'ecoulement and du transfert de chaleur en convection mixte laminaire dans des conduites rectangulaires horizontales pour des valeurs elevees des nombres de Reynolds et Rayleigh as mentioned in this paper.
Abstract: Etude theorique des caracteristiques de l'ecoulement et du transfert de chaleur en convection mixte laminaire dans des conduites rectangulaires horizontales pour des valeurs elevees des nombres de Reynolds et Rayleigh
TL;DR: The simple example (n = 1) is given for classroom presentation when teaching UMPU tests and is intended to dispel a common belief that the labels UMP and UMPU are synonymous.
Abstract: The simple example (n = 1) is given for classroom presentation when teaching UMPU tests. Along with the more general example (any n), it is intended to dispel a common belief that the labels UMP and UMPU are synonymous. A student could thus be encouraged to look beyond a single best test among unbiased tests by trying alternative methods. The issue will then be one of practicality: The importance of using an unbiased test that is not very powerful must be weighed against the power superiority, in a large subset of the alternative parameter space, of a biased test. 4. CONCLUSION
TL;DR: In this article, the authors considered a non-cooperative N-person discounted Markov game with a metric state space, and defined the total expected discounted gain under some conditions imposed on the objects in the game system.
TL;DR: In this paper, an iterative method together with the orthogonal collocation method is proposed for the evaluation of the effectiveness factor and the substrate concentration profile within the enzyme particles, and numerical results offer an alternative analytical proof for the observation that under strong internal diffusion control the apparent operational stability of immobilized enzyme is improved.
TL;DR: In this paper, a continuous flow pilot scale foam flotation plant was used to remove hexavalent chromium from dilute simulated wastewater in order to remove pH adjustment by precipitate flotation, and the effects of varying hydraulic loading rate and the ferrous sulfate dose were studied.
Abstract: Hexavalent chromium was removed from dilute simulated wastewater in a continuous flow pilot scale foam flotation plant. Cr(VI) was reduced to Cr(III) with ferrous sulfate, and the floc resulting on pH adjustment was then removed by precipitate flotation. Sodium lauryl sulfate was used as the carrier surfactant. Effluent Cr concentrations below 0.5 mg/L are easily achieved over the pH range 4.5 to 7.0. The effects of varying the hydraulic loading rate and the ferrous sulfate dose were studied.
TL;DR: In this paper, the effect of interference between the duct apertures at its two ends is identified in the calculations of radiation impedance, reflection coefficient, and the far field radiation pattern.
TL;DR: Results suggest that the new base change found in IVS-2 causes aberrant splicing of the beta-globin mRNA precursor, which is doubly heterozygous for beta 0- and beta +-thalassemia.
TL;DR: It is suggested that N. nigricollis phospholipase A2 has a direct, non-enzymatic, cardiotoxic action that is not due to the accumulation ofphospholipid hydrolytic products, and on the basis of prior studies with chemically modified phosphate A2 enzymes.
TL;DR: Raman spectra of tetracyanoethylene (TCNE) deposited on rough Ag films were studied with an Ar+ laser as mentioned in this paper, where TCNE was found to form a charge transfer mechanism.
TL;DR: In this paper, a method for the preparation of bicyclo[2.2]oct-5-ene-2, 3-diones from catechols via masked o-benzoquinones is presented.
Abstract: The cycloadditions of the title compound, 1, a masked 3, 6-dipropyl-o-benzoquinone to various disubstituted (diethyl maleate, diethyl fumarate, trans- and cis-stilbene, and cycloheptene) and monosubstituted alkenes (methyl acrylate, methyl vinyl ketone, styrene, ethyl vinyl ether, and 1-hexene) have been studied; the yields of the Diels-Alder adducts, 2, are generally high (> 75%) except for stilbenes. These adducts are effectively transformed into the corresponding bicyclo[2.2.2]oct-5-ene-2, 3-diones, 3, whose stereochemistries are determined from the ring current effect of the respective quinoxalines, 4, on the chemical shifts of the vinyl and the methine protons and/or the lanthanide (Eu(fod)3) induced shift on the pertinent protons of 3. It is interesting to note that the quinoxaline ring current makes the vinyl protons down-field shifted by 0.15–0.27 ppm whereas the methine protons (R3=H) syn to the quinoxaline moiety up-field shifted by 0.18–0.39 ppm as compared to the chemical shifts of the corresponding protons in 3. The transformations of α-diketones 3 into the corresponding 1, 3-cyclohexadienes, 5, by irradition with a Hanovia medium pressure lamp through a uranium glass filter are almost quantitative. The present study provides facile and effective methods for the preparation of bicyclo[2.2.2]oct-5-ene-2, 3-diones and 1, 3-cyclohexadienes from catechols via masked o-benzoquinones.
TL;DR: In this paper, a new distribution-free procedure obtains s-confidence intervals for the reliability in the stress-strength model, based on the coverage probability and average-length criteria, a simulation study compared the procedure with other methods.
Abstract: A new distribution-free procedure obtains s-confidence intervals for the reliability in the stress-strength model. Based on the coverage probability and average-length criteria, a simulation study compared the procedure with other methods. Generally the proposed intervals perform best in maintaining nominal coverage probabilities.
TL;DR: In this paper, the authors studied the kinetics of the thermal decomposition of aluminum sulfate in a Perkin-Elmer thermobalance and found that the contracting volume model was the best one for describing the kinetic results under isothermal conditions.