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131.
Aluminum hydroxide was used as a reactive filler to elastomers prepared from poly(oxypropylene)glycol (PPG), 2,4-tolylene diisocyanate (TDI), and 1,4-butane diol (BD). Mechanical properties, dynamic mechanical properties, and thermal properties were measured. Morphologies were observed by use of X-ray diffraction and scanning electron micrographs. The model reaction of isocyanate and aluminum was also studied. It was found that aluminum hydroxide fillers can be used for cost reduction without any detrimental effects on mechanical properties. Scanning electron micrograph studies of freshly cut surfaces of the aluminum filled elastomers showed that aluminum hydroxide is highly compatible with the elastomer. © 1994 John Wiley & Sons, Inc.  相似文献   
132.
N-Methacryloylcarbamate (N-MAC), which is an original monomer of Nippon Paint, is a heterofunctional monomer which has a polymerizable double bond and an acylcarbamate group in the same molecule. It has four characteristic properties, which have been developed for use in coatings. These are: a molecular weight that can be controlled easily by the amount of radical initiator used irrespective of the kind of acylcarbamate; the reactivity of the acylcarbamate group in the polymer is lower with an alcohol than in a monomer. However, the reactivity of the acylcarbamate group in the polymer with alcohol is much higher than that of carbamate group with alcohol; a curing temperature dependent on the kind of acylcarbamate group; and an acylcarbamate group that can react with a low nucleophilic active hydrogen such as that of a secondary alcohol. An electrodeposition paint has been developed from these properties since the activated acylcarbamate group in the N-MAC polymer makes it possible to design a low temperature crosslinking system, the flexibility in design of the main resin with respect to the active hydrogen makes it possible to improve the storage stability because of high reactivities of N-MAC polymer with active hydrogen compounds, and a core/shell structure makes it possible to make low temperature crosslinking compatible with good storage stability.  相似文献   
133.
An episode of malignant hyperthermia occurring in a 42-year-old man undergoing hypothermic cardiopulmonary bypass is reported. Malignant hyperthermia is a syndrome initiated by a hypermetabolic state of skeletal muscle. A patient presented for correction of an acyanotic tetralogy of Fallot. The coincidental usage of hypothermic cardiopulmonary bypass obscured the classical presenting sings and symptoms of the malignant hyperthermia. And the disease of tetralogy of Fallot made the syndrome difficult to manage. Although the clinical diagnosis of malignant hyperthermia is difficult to be confirmed, when it is suspected, it is prudent for the case to be initially treated as malignant hyperthermia.  相似文献   
134.
Simple chest X rays on film are the most common type of image in medical diagnosis. However, amongst the various types of medical X-ray images, they require the highest level of display quality due to the fact that the body structures they capture on film have varying degrees of permeability to X rays. Conventional high-definition digital display technology has not always been able to match the quality of such film images. This has been a major impediment against progress toward the complete digitization of simple chest X rays. The intent of this paper is to examine that, when applied to medical diagnosis of chest X rays, super-high-definition (SHD) images (digital images with resolution exceeding that of HDTV) are capable of producing a level of quality of diagnostic accuracy on a par with conventional film images. We will start out by seeking out the overall transmission characteristics of a system that uses digital radiography and a film digitizer to digitize images. We will then derive gray-scale transform characteristics based on the luminance linear method for approximating, as closely as possible on a CRT, film images on a light box that have wide dynamic range and high luminance. Finally, we will present the results of image evaluation experiments using high-definition CRT monitors. These results indicate that conventional film images and those on super-high-definition CRT monitors have nearly the same quality. They will also show that the contrast mapping selected by radiologists and theoretical luminance linear characteristics were almost the same except in low-luminance regions. We will also discuss radiologists' comments on CRT monitors after they participated in the evaluation experiment.  相似文献   
135.
136.
β′-(BEDT-TTF)(TCNQ) is a compound of BEDT-TTF (=ET) and TCNQ molecules aligned orthogonally with each other, forming two-dimensional sheets and one-dimensional columns of 1/4-filled π band, respectively. It is known that the metal-insulator transition occurs at 330 K at ambient pressure. We have measured the electronic spin susceptibility by means of the EPR-NMR method at 50 MHz, and the angular dependence of g-factor and line width of EPR both at Q (34 GHz) and W (94 GHz) band. We successfully confirmed that the antiferromagnetic transition occurs in ET sheets and TCNQ columns, independently.  相似文献   
137.
We discuss the properties of comb-like dispersion profiled fiber (CDPF) for an optical soliton transmission. It is found that the CDPF in which the standard single-mode fiber is placed both at the first and at the end of each section is more suitable to reduce dispersive waves if chirp-free transform limited optical pulse is used as a light source. A 10-ps optical soliton transmission experiment is performed in such a CDPF over 1000 km with the amplifier spacing of 80 km that corresponds to 3.1 times the dispersion distance.  相似文献   
138.
Lymphoreticular malignancies, collectively called posttransplant lymphoproliferative disorders (PTLD), eventually develop in 2-5% of organ transplant recipients. They frequently undergo regression when immunosuppression is reduced or stopped. This feature has been associated with a previous or de novo Epstein-Barr virus (EBV) infection. We herein describe immunotherapy with autologous lymphokine-activated killer (LAK) cells in seven patients with PTLD (four EBV-positive patients and three EBV-negative patients). Autologous peripheral blood mononuclear cells were obtained by leukapheresis, depleted of monocytes, and cultured in the presence of interleukin 2 for 10 to 11 days. A single dose of 5.2 x 10(9) to 5.6 x 10(10) LAK cells was given intravenously. Systemic interleukin 2 was not administered. The four patients with EBV+ PTLD had complete tumor regression; two of them developed controllable rejection. Three patients are well 13-16 months after treatment; the fourth patient died of pneumonia 41 days after infusion. Three patients with EBV- lymphomas had no response despite prior evidence that their tumors also were subject to immune surveillance. Two of these three patients died after being given other treatment, and the third patient has persistent tumor. In conclusion, autologous LAK cell infusion was effective for treatment of four EBV+ organ transplant recipients. LAK cell efficacy for three patients with EBV- PTLD was not evaluable under the management circumstances in which this treatment was utilized.  相似文献   
139.
The possibility of near infrared (NIR) spectroscopy to measure the amount of bacterial contamination in shredded cabbage was investigated. NIR measurements in the short wavelength region from 700 to 1100 nm were done using two types of saline solutions: one was used to stomach with the samples as the conventional method and the other was used to wash the outer surface of the sample to examine the possibility of a non‐destructive method. Partial least squares regression (PLS) was used to develop the equations for bacterial amount. Spectra from the stomacher solution and the washing solution produced similar results. Sufficiently accurate results could be obtained with the bias‐corrected standard error of prediction (SEPs) of 0.46 log CFU g?1 for the stomacher solution and 0.44 log CFU g?1 for the washing solution. NIR spectroscopy was clarified to be a rapid and non‐destructive method for prediction of bacterial contamination in shredded cabbage.  相似文献   
140.
Temperature characteristics of the open-circuit voltage (Voc) were investigated in the temperature range from 30°C to 240°C for the InGaP/InGaAs/Ge triple-junction cells. Also, single-junction cells that had the similar structure to the subcells in the triple-junction cells were studied. In the high-temperature range (from 170°C to 240°C), the temperature coefficients of Voc of the InGaP/InGaAs/Ge triple-junction solar cell (dVoc/dT) were different from those in the low-temperature range (from 30°C to 100°C). This is because photo-voltage from the Ge subcell becomes almost 0 V in the high-temperature range. It was found that the open-circuit voltage of a Ge single-junction cell reduced to almost 0 V temperatures over 120°C under 1 sun condition.  相似文献   
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