Superstructural description of deformation process in uniaxial extension of preoriented isotactic polypropylene

The strains on uniaxial extension of preoriented isotactic polypropylene are separated over the whole range of deformation into three processes: crystallite boundary slip (A₁ process), uniform shear deformation of crystallites (A₂ process), and restoration of molecular orientation from the sheardeformed state (ā₂ process). They are separately evaluated by the use of the parameters of superstructure varying in deformation. Both the A₁ and A₂ processes predominate before the A₂ → ā₂ transition takes place. Wide- and small-angle x-ray goniometries detect this transition. After the A₂ → ā₂ transition takes place, the specimen cannot be deformed by the A₁ or A₂ process, but by a molecular process such as pulling out the isolated extending chains from the folded chain crystals followed by their refolding. From the quantitative evaluations of the strains associated with the A₁ and A₂ processes it is deduced that the initial shear compliance for the A₁ process is smaller than that for the A₂ process.     

Size effect in compressive strength of concrete

Three series of experiments were carried out to examine the effect of the size and type of aggregate on the size effect in the compressive strength of concrete from the standpoint that it may result from the geometrical heterogeneity of concrete system. According to the test results, the size effect in the concrete strength was closely related to the ratio of the diameter of specimen to that of aggregate (D/d). The compressive strength of river sand and gravel concrete and glass ball concrete increases with the increase of the size of specimen provided that the value of D/d is smaller than about 8.     

A study on the adsorption of dialkyldimethyl ammonium chloride

A study was made on the structure, adsorption behavior toward fabrics and dependence upon particle size of an aqueous dispersion of di(hydrogenated tallow)dimethyl ammonium chloride (purified Arquad 2HT), the most widely used softener base. From the results of analyses by X-ray diffraction, differential scanning calorimetry (DSC) and electron microscopy, it was found that the dispersed phase of Arquad 2HT dispersion consisted of hydrated particles having a similar structure to that of the multilayered liposomes (or vesicles) of phospholipids and that these particles were adsorbed onto fabrics by softening treatment It was also found that finely dispersed particles showed better softening and antistatic performances in addition to a superior storage stability, due to their higher rate and uniformity of adsorption compared to roughly dispersed particles.     

Amplifying shear deformation of finger pad increases tracing distances

Human sensory inputs and motor outputs mutually affect one another. We pursue the idea that a tactile interface can influence human motor outputs by intervening in sensory–motor relationships. This study focuses on the shear deformation of a finger pad while a person traces a line or circle. During these tracing movements, the finger pads were deformed using a tactile interface. The tracing distances increased when the finger pad deformations were amplified by the tactile interface, which indicates that the intervention in the haptic sensorimotor loop affected the tracing movements. Elucidation of such interaction between the tracing movements and the shear deformations of finger pads enhances the understanding of human-assistive haptic techniques.     

Growth modulation of human tumor cells by a growth-inhibiting activity derived from tumorigenic V79 Chinese hamster cells

A growth-inhibiting activity was identified in supernatants of the neoplastic V79 Chinese hamster cell line based on its ability to inhibit the proliferation of the same cell line. The partially purified activity, provisionally termed "growth inhibiting factor" (GIF) activity, inhibited the growth of a wide variety of human tumor cells, but not various normal human fibroblasts. This species-nonspecific activity was reversible, saturable, and highly potent in tumorigenic cell lines, and was noted in both monolayer culture and in soft agar. The inhibitory activity of GIF was also exhibited in a chemically defined serum-free medium supplemented with insulin and transferrin. GIF activity was stable to acid, heat, trypsin, and dithiothreitol but sensitive to alpha-chymotrypsin. The pattern of growth modulation by GIF on V79 cells was apparently different from those exhibited by bifunctional peptides such as transforming growth factor-beta, tumor necrosis factor-alpha, and interleukin-1-alpha. In addition, GIF activity cannot be ascribed to these cytokines based on the physicochemical and immunologic properties. Although GIF has yet to be purified to homogeneity, these data suggest that GIF might be a novel growth regulator which has a critical role in regulating growth of V79 cells. The growth modulation of tumor cells by this tumor-derived growth inhibiting activity suggested the presence of an autocrine growth regulatory mechanism even in tumor cells.     

Radiocarbon dating of charred human bone remains preserved in urns excavated from medieval Buddhist cemetery in Japan

For a preliminary test of ¹⁴C dating of cremated human remains, we have collected charred bone and wood–charcoal fragments from cremated remains contained in cinerary urns that had been excavated from medieval Buddhist cemetery at the Hoenji temple in Aichi prefecture, central Japan. More than 230 urn vessels were discovered from the excavated area of ca. 14 m wide and 14 m long. The identification of charred bone or charcoal fragments among the remains was performed by observation of surface appearance, inspection of fine structures by a microscope, bubble formation during the HCl treatments in preparing target material for AMS ¹⁴C dating, carbon and nitrogen contents, δ¹³C and δ¹⁵N values of the fragments. All ¹⁴C ages obtained for the samples that were identified as charred bone remains were almost consistent with the archeological age estimated based on typological analysis of respective urns. On the other hand, some ¹⁴C ages for the remains identified as wood charcoal, which had been produced from firewood or a wooden coffin during the cremation, were not consistent with archeological estimation, shifting toward older ¹⁴C ages, most probably as the result of old wood effect.     

Interface properties of SiOxNy layer on Si prepared by atmospheric-pressure plasma oxidation-nitridation

SiO_xN_y films with a low nitrogen concentration (< 4%) have been prepared on Si substrates at 400°C by atmospheric-pressure plasma oxidation-nitridation process using O₂ and N₂ as gaseous precursors diluted in He. Interface properties of SiO_xN_y films have been investigated by analyzing high-frequency and quasistatic capacitance-voltage characteristics of metal-oxide-semiconductor capacitors. It is found that addition of N into the oxide increases both interface state density (D_it) and positive fixed charge density (Q_f). After forming gas anneal, D_it decreases largely with decreasing N₂/O₂ flow ratio from 1 to 0.01 while the change of Q_f is insignificant. These results suggest that low N₂/O₂ flow ratio is a key parameter to achieve a low D_it and relatively high Q_f, which is effective for field effect passivation of n-type Si surfaces.