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211.
Consistent calculation of fugacities of fluid mixtures remains as one of the most important subjects in contemporary molecular
thermodynamics. In practice, equations of state (EOSs) and gE-models have been used. However, most EOSs are erroneous for condensed phases at high densities and gE-models are inapplicable for pressuresensitive systems. Recently to remedy the shortcomings in both approaches, there has
been a surge of new gE-EOS mixing rules. By equating any set of EOS and gE-models, the limitations in both approaches could be resolved significantly. However, the self-consistency in the underlying
concept of those mixing rules remains controversial. During the last several years, the present authors proposed a new lattice-fluid
EOS and its simplification relevant to phase equilibrium calculations. Without employing any gE-EOS mixing rule and with only two parameters for a pure component and one adjustable interaction energy parameter for a binary
mixture, results obtained to date demonstrated that the EOSs are quantitatively applicable to a great variety of phase equilibrium
properties of mixtures, especially, for complex and/or macromolecular systems. In the present article we summarize the EOSs
and extended the applications to liquid-liquid Equilibria. In part I, we discussed briefly the molecular thermodynamic aspects
of general derivation of the EOS and a brief discussion of applying the EOSs to pure fluids while the illustrative application
to various real mixture systems is discussed in part II. 相似文献
212.
Diffuse villous hyperplasia of the choroid plexus, which is distinct from bilateral choroid plexus papillomas, is extremely rare and is often associated with hydrocephalus due to the overproduction of cerebrospinal fluid (CSF). The authors describe an infant with hydrocephalus, diagnosed by computerized tomography scanning, who developed ascites following placement of a ventriculoperitoneal shunt and, subsequently, demonstrated excessive CSF production when the shunt was externalized. The patient was later successfully treated by placement of a ventriculoatrial shunt. Magnetic resonance imaging demonstrated diffuse villous hyperplasia of the choroid plexus as the cause of the patient's hydrocephalus. The literature on diffuse villous hyperplasia of the choroid plexus is reviewed. 相似文献
213.
A. Inoue B. G. Kim K. Nosaki T. Yamaguchi T. Masumoto 《Journal of Materials Science Letters》1992,11(12):865-867
On leave from: Honda Research and Development Co., Ltd, Wako 351-01, Japan. 相似文献
214.
The crystallization of poly(phenylene sulfide) (PPS) in a polymer–magnetic Nd—Fe—B powder suspension was studied. Isothermal crystallization behavior was analyzed by way of differential scanning calorimetry, and the kinetics were described via the Avrami equation. The Avrami parameters and the crystallization times were strongly affected by both the particle size and the presence of a coupling agent coated on the filler particles. The small Nd—Fe—B particles exhibited long induction and half‐times, whereas the large particles tended to have short crystallization times. Particles ranging from 38 to 150 μ appeared to have similar crystallization times and to have no significant change in the value of Avrami index with melt crystallization temperature. As a result of these analyses, the dynamic mechanical properties were determined to correlate the fundamental polymer crystallization characteristics and the physical properties of the PPS binder. The enhancement of the wetting of the filler to the binder was promoted through the coupling agent, as confirmed by dynamic mechanical testing performed on the samples. The storage modulus typically decreased because of the presence of the uncoated small particles. Conversely, the loss modulus was enhanced because of the presence of the coated small particles in the PPS binder. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1091–1102, 2002 相似文献
215.
H Ota T Katsuyama S Nakajima H El-Zimaity JG Kim DY Graham RM Genta 《Canadian Metallurgical Quarterly》1998,29(8):846-850
Helicobacter pylori seem to avoid areas of intestinal metaplasia in the gastric mucosa, but attachment of these bacteria to epithelium with the appearance of incomplete intestinal metaplasia has been documented. To characterize the nature of the epithelium to which H pylori was attached, we carried out an immunohistochemical study using monoclonal antibodies against gastric surface mucous cell mucins (M1), blood group-related carbohydrates antigens (Le(a), sialyl Le(a), Le(b), type 1H, and type 2H) and sialyl Tn antigen. The results of this study suggest that these areas of H pylori attachment represent a hybrid epithelium whose cells share characteristics of both gastric surface mucous cells and intestinal metaplastic cells. Whether all areas of incomplete intestinal metaplasia represent an intermediate stage between the normal gastric epithelium and the fully developed complete type of metaplasia remains to be determined. 相似文献
216.
217.
In normal subjects, if an acoustic startle stimulus is immediately preceded by a small brief change in background noise intensity, the magnitude of the subsequent startle response is decreased. This prepulse inhibition (PPI) of an acoustic startle response has been shown to be associated with sensorimotor gating. PPI is disrupted in schizophrenic patients and has been linked to attentional disorders characteristic of this disease. We tested the effects of (-)-nicotine, (0.19, 0.62, and 1.9 mumol/kg IP) (equivalent to 0.03, 0.1, and 0.3 mg/kg base) and the nicotinic cholinergic receptor (nAChR) channel blocker, mecamylamine (5.0 and 50 mumol/kg IP) (equivalent to 1.0 and 10.0 mg/kg) on PPI of the acoustic startle response in the rat. Nicotine increased the PPI at the lowest prepulse signal levels but not at the stronger levels. Mecamylamine was without effect at 5.0 mumol/kg, but the 50 mumol/kg dose decreased the inhibition at both weak and strong prepulse (PP) levels. Mecamylamine (5.0 mumol/kg) pretreatment did not block the (-)-nicotine-induced increase in PPI. Lobeline (0.19, 0.62, 1.9, and 6.2 mumol/kg IP) (equivalent to 0.071, 0.23, 0.71, and 2.3 mg/kg) was without effect. These results are consistent with a mecamylamine-insensitive effect of nicotine to improve gating in normal rats. The nAChR subtype involved in producing nicotine's increase of PPI needs further investigation. 相似文献
218.
Arylsulfate sulfotransferase purified from Eubacterium A-44 has higher specific activity than the enzymes from Klebsiella K-36 and Haemophilus K-12. Propylparaben and butylparaben were good substrates among several parabens. The antibacterial activity of parabens was reduced by the sulfation of the phenolic hydroxy group. Tyrosine-containing peptides, kyotorphin, enkephalin and cholecystokinin non-sulfate, were effective as acceptor substrates by A-44, K-36 and K-12 sulfotransferases. 相似文献
219.
220.
Kinetics of zinc oxide formation from zinc sulfide by reaction with lime in the presence of water vapor 总被引:1,自引:0,他引:1
A novel reaction scheme for transforming certain metal sulfides to the corresponding oxides has been developed. In this process,
steam oxidizes the sulfide into the oxide, and the hydrogen sulfide produced reacts with lime to form calcium sulfide and
regenerate steam. There is no net consumption or generation of gaseous species. Thus, the overall reaction can be carried
out in a closed system as far as the gas phase is concerned. This eliminates the possibility of emitting hydrogen sulfide
out of the reactor. Only certain metal sulfides are thermodynamically amenable to this treatment. In this paper, the reaction
of ZnS to ZnO by this scheme is described, together with a detailed formulation of the rate equation for the overall reaction
based on the kinetics of the component gas-solid reactions. Although the present work was done with CaO, other suitable oxides
may be used in its place. A further potential application of this process is to the selective oxidation of certain sulfide(s)
from complex sulfide ores as a treatment prior to the separation of minerals. 相似文献