Determination of density changes during melting by X-ray absorption

Continuous measurement of X-ray transmission through a sample confined in a rigid holder permits thermal expansion coefficients of solids, density change during melting, and thermal expansion coefficients of liquids to be determined by a single method as temperature is increased. Application to melting of pure metals and binary eutectics is illustrated for aluminum, the aluminum-silicon eutectic, and the aluminum-copper eutectic. Parameters affecting design and operation of the system are discussed. Formerly Postdoctoral Fellow, University of Delaware formerly Graduate Student,University of Delaware.     

Judgment of personal characteristics and emotions from nonverbal properties of speech.

A person's changing emotional state and relatively stable personal characteristics may be judged from nonverbal properties of his voice. These properties include such elements as timbre, inflection, and stress, which accompany the actual words spoken but are not a direct part of them. Many studies have used inadequate measures as the dependent criterion for the traits being judged, and no method of eliminating the verbal content has been wholly successful. The evidence does show, however, that some validity of judgment is possible. Acoustic analysis has been little used; it could increase the objectivity of studies. Individual differences among listeners and the relationship of voice to psychopathology have been particularly neglected areas in research. (96 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Review of Modern learning theory. A critical analysis of five examples.

Reviews the book "Modern learning theory. A critical analysis of five examples," by William K. Estes et al. (see record 2004-21803-000). This book is the product of the Dartmouth summer conference on learning theory, held in the summer of 1950 under the auspices of the Social Science Research Council, with funds supplied by the Carnegie Corporation. Each of the five sections is devoted to one learning theorist. The authors have followed a guiding outline for evaluating each theory, including a discussion of the structure of the theory, methodological characteristics, and, finally, an over-all appraisal of empirical content and adequacy. The issues raised in the book will undoubtedly be challenged and discussed separately by those friendly to the various theories. The critical task which the authors set themselves was admirably done, and we may be thankful for it. The homogeneity in conception of what constitutes a good theory reflects in part the homogeneity of background of those who found it congenial to meet together. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relative strength of scleral tunnel incisions with internal corneal lips constructed in cadaver eyes

We constructed scleral tunnel wounds with internal corneal lips and sutureless closures in ten cadaver eyes without previous intraocular surgery. Each wound differed in width, total incision length, and internal corneal lip size. At a low and high range of initial intraocular pressure (IOP, 10 to 15 mm Hg or 20 to 25 mm Hg), we compared the wounds' resistance to leakage during application of external pressure. A square wound with a 4.0 mm width and 4.0 mm overall length, including a 1.5 mm corneal lip, had the optimum wound dimensions. These produced a stable incision that resisted leakage at external pressures up to 525 pounds per square inch equally well at both IOP ranges. Leakage occurred at lower external pressures for wounds with greater width, smaller corneal lips, or wound widths that were greater than wound lengths; such wounds were also more prone to leakage at the low IOP range. When constructed properly and adequately, the 4.0 mm wide scleral tunnel incision with 1.5 mm internal corneal lip is a strong and safe wound for sutureless cataract surgery.     

Development and performance of a fluence rate distribution model for a cylindrical excimer lamp

Ultraviolet disinfection systems employing excimer lamp technology represent a suitable choice in situations where lamp mercury content is restricted, or otherwise undesirable. The XeBr* excimer lamp emits nearly monochromatic radiation at 282 nm, and dose-response experiments with Bacillus subtilis spores have shown that it is germicidally effective. A numerical model was developed to describe the fluence rate (E') distribution emanating from a cylindrical XeBr* excimer lamp, based on liquid water or air as the surrounding medium. The E' distribution model is based on physical phenomena that are known to govern excimer lamps; the model also accounts for refraction, reflection, and absorbance effects of the quartz lamp envelope and the media surrounding the lamp. Measurements of the E' distribution by local actinometry supported the validity of the numerical model. This model can be used as a component (submodel) of a more general model to simulate the behavior of photochemical reactors that employ excimer lamps as their source of electromagnetic radiation.     

The solubility of ZnO and ZnAl2O4 in cryolite melts

The solubilities of ZnO and ZnAl₂O₄ in cryolite-alumina melts at 1020 °C have been measured. ZnAl₂O₄ is the stable solid phase at Al₂O₃ contents greater than 1.45±0.2 wt pct. The results can be represented (in terms of wt pct Zn in solution and in the range 1.2 to 13.6 pct Al₂O₃) by

A Parallel Method for Earth Mover’s Distance

We propose a new algorithm to approximate the Earth Mover’s distance (EMD). Our main idea is motivated by the theory of optimal transport, in which EMD can be reformulated as a familiar \(L_1\) type minimization. We use a regularization which gives us a unique solution for this \(L_1\) type problem. The new regularized minimization is very similar to problems which have been solved in the fields of compressed sensing and image processing, where several fast methods are available. In this paper, we adopt a primal-dual algorithm designed there, which uses very simple updates at each iteration and is shown to converge very rapidly. Several numerical examples are provided.     

Carbonization and liquid-crystal (mesophase) development. 16. Carbonizations of soluble and insoluble fractions of coal-extract solution

A coal-extract solution prepared by extraction of a coking coal (CRC 301a) with anthracene oil by the National Coal Board is separated into fractions using solvents of increasing solvent power. These fractions are carbonized to 823 K and the optical textures of resultant cokes are assessed. The objective of the study is to examine the role of the molecular components of the coal-extract solution including the residual anthracene oil in mechanisms of formation of the optical texture of the anisotropic coke. Generally, the low-molecular-weight fractions of the coal-extract solution produce cokes with larger sized optical textures than the coke from the parent coal-extract solution. The higher-molecular-weight fractions produce cokes with smaller sized optical textures. Isotropic coke is produced from material which is not soluble in benzene and tetrahydrofuran. Within this parent-coal-extract solution it would appear that the dominant partner effect is influential over the size of the optical texture of coke from the coal-extraction solution, that is the minor component of smaller molecules controls the necessary growth of liquid crystals. Also, the presence of anthracene oil augments the size of optical texture of resultant cokes by providing the necessary physical fluidity of the system and possibly some chemical stability.     

An analysis of daylighting performance for office buildings in Hong Kong

Daylighting has often been recognized as a useful source of energy savings and visual comforts in buildings. Occupants expect good daylight in their working spaces. The quality and quantity of natural light entering a building depend on both internal and external factors. In Hong Kong, commercial building accounts for the major building energy use and electric lighting is one of the major electricity-consuming items. This paper studies the daylighting performance and energy implications for office buildings. A total of 35 commercial buildings have been selected in the survey. Key building parameters affecting daylighting designs are presented. Two typical office blocks were further analysed based on a lighting simulation program. The daylighting performance was evaluated in terms of daylight factor, room depth and glare index. It has been found that the daylighting performance for office buildings is quite effective. About one-third of the office areas that are near the perimeter regions have an average daylight factor of 5%. For inner region of deep plan offices, some innovative daylighting systems such as light redirecting panels and light pipe could be used to improve the daylighting performance. In general, the office building envelop designs are conducive to effective daylighting and proper daylight linked lighting controls could save over 25% of the total electric lighting use.     

Steam purification for the removal of graphitic shells coating catalytic particles and the shortening of single-walled carbon nanotubes

Purification and shortening of single-walled carbon nanotubes (SWNTs) is carried out by treatment with steam. During the steam purification the graphitic shells coating the catalytic metal particles are removed. Consequently, the exposed catalytic particles can be easily dissolved by treatment with hydrochloric acid. No damage to the carbon nanotube tubular structure is observed, even after prolonged treatment with steam. Samples are characterized by HRTEM, TGA, magnetic measurements, Raman spectroscopy, AFM, and XPS.