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81.
The general characteristics of eight fabric groups as measured by the KES-F system are described. These fabric groups are divided by fibre content, fabric construction and special finishing treatment. Using silk fabric as a reference, caustic-reduced polyester fabrics exhibit strong silk-like characteristics except in their surface properties. Liquid ammonia-treated cotton fabrics also possess a certain silky hand. Micro-fibre fabrics are soft and smooth, but they do not have the high Kishimi hand which is typical of silk fabrics. Fabric construction has some influence on fabric stiffness, but not on hysteresis. Polyester-lining fabrics have high bending stiffness and polyester/cotton fabrics have very high shear stiffness and hysteresis. These two groups of fabrics are the least silk-like. Shear properties and bending hysteresis appear to be the most important factors affecting the hand of the fabrics studied. 相似文献
82.
Two commercial PET yarns, one as-spun and the other highly crystalline and drawn, were annealed at l8°C under various conditions. Mechanical and thermal-response measurements were made under high transient-heating conditions by using a UMIST-built Universal Fibre Tester (UFT). Differential-scanning-calorimetry (DSC) measurements were also made. A middle endotherm was observed on DSC traces for both the PET samples that had been annealed freely (free to shrink). Further thermo-mechanical treatments of these pre-annealed samples were made and thermal, creep, tangent-modulus, and other mechanical properties are recorded. The experimental results show structural instability in the fibre morphology irrespective of the process histories. 相似文献
83.
A. Seal A. K. Dalui M. Banerjee A. K. Mukhopadhyay K. K. Phani 《Bulletin of Materials Science》2001,24(2):151-155
The biaxial flexural strength, Young’s modulus, Vicker’s microhardness and fracture toughness data for very thin, commercial,
soda-lime-silica cover slip glass (diameter, D-18 mm, thickness, T-0.3 mm; T/D ≈ 0.02) are reported here. The ball on ring
biaxial flexure tests were conducted at room temperature as a function of the support ring diameter (≈ 10–20 mm) and cross
head speed (0.1–10 mm min−1). In addition, the Weibull modulus data were also determined. The Young’s modulus data was measured using a linear variable
differential transformer (LVDT) from biaxial flexure tests and was checked out to be comparable to the data obtained independently
from the ultrasonic time of flight measurement using a 15 MHz transducer. The microhardness data was obtained for the applied
load range of 0.1–20 N. The fracture toughnessK
IC data was obtained by the indentation technique at an applied load of 20 N. 相似文献
84.
Wound healing is a series of different dynamic and complex phenomena. Many studies have been carried out based on the type and severity of wounds. However, to recover wounds faster there are no suitable drugs available, which are highly stable, less expensive as well as has no side effects. Nanomaterials have been proven to be the most promising agent for faster wound healing among all the other wound healing materials. This review briefly discusses the recent developments of wound healing by nanotechnology, their applicability and advantages. Nanomaterials have unique physicochemical, optical, and biological properties. Some of them can be directly applied for wound healing or some of them can be incorporated into scaffolds to create hydrogel matrix or nanocomposites, which promote wound healing through their antimicrobial, as well as selective anti‐ and pro‐inflammatory, and proangiogenic properties. Owing to their high surface area to volume ratio, nanomaterials have not only been used for drug delivery vectors but also can affect wound healing by influencing collagen deposition and realignment and provide approaches for skin tissue regeneration.Inspec keywords: skin, wounds, cellular biophysics, drug delivery systems, tissue engineering, hydrogels, nanocomposites, proteins, nanomedicineOther keywords: wound healing materials, nanomaterials, nanotechnology, proangiogenic properties, proinflammatory properties, collagen deposition, drug delivery vectors, skin tissue regeneration 相似文献
85.
M. Jackson G. R. Sudhakaran A. Silveira Jr. I. Mukhopadhyay R. M. Lees 《Journal of Infrared, Millimeter and Terahertz Waves》1999,20(4):583-594
The high resolution Stark spectra of the singly deuterated methanol isotope, CH3OD, have been studied using the HCN laser with Stark fields up to approximately 60 000 V/cm. Numerous families of absorption lines have been observed in both parallel and perpendicular polarizations, resulting in the following assignments: with the 311 μm line – J K = 181 ← 180 E 2, υ t = 1; and with the 337 μm line – J k = 64 ← 53 E 2, υ t = 0 and J K = 146 ← 135 A, υ t = 1. Zero-field frequencies for the assigned transitions are in agreement with Fourier transform measurements and those calculated from the available molecular constants. 相似文献
86.
87.
Indranath Mukhopadhyay Romola D'Cunha 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(8):1255-1273
In this paper the Backward Wave Oscillator (BWO) based spectroscopy technique and its application to molecular spectroscopy especially to diatomic molecules have been discussed. This is a new and electronically controlled technique with enormous capabilities most of which are yet to be exploited. This paper also presents a part of the culmination of the collective efforts in developing a cohesive and consolidated enunciation of the spectroscopic parameters and their relationship to effective molecular Hamiltonians for diatomic formalism, linear four- atomic formalism & quasi-linearity, Watson Hamiltonian and the complexities in symmetric and asymmetric top spectral structures and its relationship to optical pumping and / or interstellar space. All these considered together present a beautiful and consistent picture of molecular spectroscopy and THz Electromagnetic sources. 相似文献
88.
A Vibrio cholerae O1 strain (1150) of the EIT or biotype and Ogawa serotype with haemagglutination (HA) activity was subjected to TnphoA mutagenesis. Out of several mutants isolated, one HA- and another HA+ mutant were further characterised. The HA- mutant showed about 50% reduction in its intestinal adherence capacity in vitro and about 9-fold decrease of its colonisation ability in vivo, as compared to the wild-type strain. Subsequent studies showed that the HA activity of strain 1150 was mediated by a mannose-sensitive haemagglutinin (MSHA). Thus, the phenotypic expression of MSHA appears to be partly responsible for the intestinal adherence and colonisation properties of strain 1150. 相似文献
89.
Multiscale morphological segmentation of gray-scale images 总被引:17,自引:0,他引:17
In this paper, the authors have proposed a method of segmenting gray level images using multiscale morphology. The approach resembles the watershed algorithm in the sense that the dark (respectively bright) features which are basically canyons (respectively mountains) on the surface topography of the gray level image are gradually filled (respectively clipped) using multiscale morphological closing (respectively opening) by reconstruction with isotropic structuring element. The algorithm detects valid segments at each scale using three criteria namely growing, merging and saturation. Segments extracted at various scales are integrated in the final result. The algorithm is composed of two passes preceded by a preprocessing step for simplifying small scale details of the image that might cause over-segmentation. In the first pass feature images at various scales are extracted and kept in respective level of morphological towers. In the second pass, potential features contributing to the formation of segments at various scales are detected. Finally the algorithm traces the contours of all such contributing features at various scales. The scheme after its implementation is executed on a set of test images (synthetic as well as real) and the results are compared with those of few other standard methods. A quantitative measure of performance is also formulated for comparing the methods. 相似文献
90.
Usable groundwater resources have strategic significance, given the arid climate of Kuwait. Assessment of groundwater resources through modelling is considered of paramount importance for sustained long‐term development of this resource. A conceptual model of the regional hydrogeology of the area has been developed based on the available data. Three aquifers were recognized within the Dammam Formation‐Kuwait Group sequence. VTDN software was used for numerical simulation of the groundwater flow in this aquifer system under steady‐state conditions. Calibration runs made to date suggest that the model is sensitive to the vertical coefficient of permeability of the aquitards and the horizontal transmissi‐vities of the aquifers. The water balance achieved shows that the contribution from the natural recharge from precipitation is insignificant. 相似文献