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41.
Kwok Y. Chow Joseph Go David J. W. Grant 《Drug development and industrial pharmacy》1986,12(3):247-264
Adipic acid crystallized from water containing various concentrations of hexanoic, octanoic or undecanoic acid was examined using differential scanning calorimetry (DSC), density measurements and dissolution rates. Parallel decreases (and increases) in the enthalpy of fusion (Δhf), entropy of fusion (ΔSf) and melting point (Tm) were observed; these changes correspond to increases (and decreases) of both the crystal energy and the concentration of crystal imperfections, resulting from the presence of additives in the crystals. When the crystals were well wetted, the rate of dissolution was inversely related to ΔHf, Tm and ΔSf in agreement with the usual assumption that “impurity” defects increase the energy and consequently enhance the dissolution rate of the crystals. The initial dissolution rate of the crystals, however, decreased with decreasing ΔHf, Tm and ΔSf, suggesting a reduction of wettability which may be caused by an associated increase in the concentration of surface irregularities. DSC appears to be a more sensitive indicator of crystal imperfection than density for doped adipic acid crystals. 相似文献
42.
The effects of oils and frying temperatures on the texture and fat content of potato crisps 总被引:1,自引:0,他引:1
The purpose of the study was to determine the effects of oils and frying temperatures on fat content and texture of potato crisps. 相似文献
43.
Roberto Parra Luis Felipe Verdeja María Florentina Barbés Christian Goñi Vanesa Bazán 《JOM Journal of the Minerals, Metals and Materials Society》2005,57(10):29-36
The Nodal Wear Model was developed to systematize the analysis of corrosion phenomena on refractory and ceramic materials
that come in contact with corrosive fluids in furnace linings. The model is based on the determination of the thermal field
in the furnace lining using a finite-element-method grid in which a second grid is defined to represent the surface of the
lining that is attacked by the molten phases. Using a control equation for the wear-corrosion thermal-activated phenomena,
a modification of the geometry is introduced and a new geometry is defined to restart the calculation.
For more information, contact Roberto A. Parra, Universidad de Concepción-Chile Departamento de Ingeniería Metalúrgica, Edmundo
Larenas 285, Concepcion, Chile; +56-41-20-46-63; fax +56-41-22-00-45; e-mail rparra@udec.cl. 相似文献
44.
Cheol Park Won Sup Lee Se-Il Go Arulkumar Nagappan Min Ho Han Su Hyun Hong Gon Sup Kim Gi Young Kim Taeg Kyu Kwon Chung Ho Ryu Sung Chul Shin Yung Hyun Choi 《International journal of molecular sciences》2015,16(1):645-659
Evidence suggests that phytochemicals can safely modulate cancer cell biology and induce apoptosis. Here, we investigated the anti-cancer activity of morin, a flavone originally isolated from members of the Moraceae family in human leukemic cells, focusing on apoptosis. An anti-cancer effect of morin was screened with several human leukemic cell lines. U937 cells were most sensitive to morin, where it induced caspase-dependent apoptosis in a dose-dependent manner. It also induced loss of MMP (ΔΨm) along with cytochrome c release, down-regulated Bcl-2 protein, and up-regulated BAX proteins. The apoptotic activity of morin was significantly attenuated by Bcl-2 augmentation. In conclusion, morin induced caspase-dependent apoptosis through an intrinsic pathway by upregulating BAD proteins. In addition, Bcl-2 protein expression is also important in morin-induced apoptosis of U937 cells. This study provides evidence that morin might have anticancer properties in human leukemic cells. 相似文献
45.
Hyoung Eun Bae Prof. Kamil Gotfryd Jennifer Thomas Hazrat Hussain Muhammad Ehsan Juyeon Go Prof. Claus J. Loland Dr. Bernadette Byrne Prof. Pil Seok Chae 《Chembiochem : a European journal of chemical biology》2015,16(10):1454-1459
Detergents are an absolute requirement for studying the structure of membrane proteins. However, many conventional detergents fail to stabilise denaturation‐sensitive membrane proteins, such as eukaryotic proteins and membrane protein complexes. New amphipathic agents with enhanced efficacy in stabilising membrane proteins will be helpful in overcoming the barriers to studying membrane protein structures. We have prepared a number of deoxycholate‐based amphiphiles with carbohydrate head groups, designated deoxycholate‐based glycosides (DCGs). These DCGs are the hydrophilic variants of previously reported deoxycholate‐based N‐oxides (DCAOs). Membrane proteins in these agents, particularly the branched diglucoside‐bearing amphiphiles DCG‐1 and DCG‐2, displayed favourable behaviour compared to previously reported parent compounds (DCAOs) and conventional detergents (LDAO and DDM). Given their excellent properties, these agents should have significant potential for membrane protein studies. 相似文献
46.
Dietary fiber and antioxidants are food constituents and functional ingredients that are generally addressed separately. Nowadays there is scientific evidence that primary characteristics of DF assigned to non starch polysaccharides and lignin (resistance to digestion and absorption in the small intestine and fermentation in the large intestine) can be extended to other indigestible food constituents that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine. The antioxidant dietary fiber concept was defined as a dietary fiber concentrate containing significant amounts of natural antioxidants associated with non digestible compounds. Hibiscus sabdariffa L flower shows in its composition an important percentage of dietary fiber and high antioxidant capacity. The infusion obtained by decoction of flowers, had been extensibility studied due to the healthy properties. In this work the principal nutritional aspects from Hibiscus sabdariffa L and its use as a possible antioxidant dietary fiber source had been considered. 相似文献
47.
Sun-Woo Kim Seok-June Chae Dae-Su Kim Jong-Un Woo Eun-Ji Kim Su-Hwan Go Jae-Min Eum Hyung-Won Kang Seung Ho Han Sahn Nahm 《Journal of the American Ceramic Society》2023,106(1):488-500
High-power piezoelectric energy harvesters (PEHs) require piezoceramics with a large kp and d33 but small εT33/ε0 values. The [0 0 1]-textured 0.96(Na, K)(Nb1−xSbx)–0.04SrZrO3 piezoceramics (x = 0.025 and 0.045) exhibited the improved electromechanical coupling factor (kp) and piezoelectric charge constant (d33); however, the increase of dielectric constant (εT33/ε0) was not significant. Further, the textured piezoceramic with x = 0.045 shows the large d33 × g33 value of 21.5 pm2/N, where g33 is piezoelectric voltage constant, indicating that texturing is a good technique to fabricate the piezoceramics for PEH. The impedance curve of the PEH consisting of the metal substrate and textured piezoceramic shows a piezoelectric resonance peak at a low frequency, which is the same as the mechanical resonance frequency of the PEH. Hence, the PEH can be considered a piezoelectric material. The figure of merit of the PEH was determined using the mechanical quality and electromechanical coupling factor calculated from the impedance curve of the PEH. A large power output of 1.7 mW was obtained from the type-1 PEH at the resonance frequency produced using the textured thick film (x = 0.045). Hence, this PEH can be used as a permanent power source for microelectronic devices in the Internet of Things. 相似文献
48.
Go Tae Kim 《Fuel》2011,90(6):2217-2223
Flame behavior in an annular diverging tube (ADT) consisting of an outer quartz tube and a tapered inner core column was investigated as a basic model for small combustion devices of various combustion space scales. Flames can be stabilized at suitable locations where the mean flow velocity is matched to the spatial average propagation velocity (SAPV). Transient variations of wall temperature and the SAPV were compared for various experimental parameters: inner core materials, burner configurations, and flow rates. It was found that a critical propagation velocity (CPV) exists that is least affected by the flow rates. The CPVs of methane, propane, and dimethyl ether (DME) were measured and a good agreement was shown between the measured CPVs and the laminar burning velocities presented in the literatures. Therefore, the ADT method can be a model for small combustion devices of various combustion space scales; furthermore, this study can be beneficial in designing and operating small combustion devices. The ADT method can also be applied in the field for in situ monitoring of the burning velocities. 相似文献
49.
K. Mani Chandy Brian Go Sayan Mitra Concetta Pilotto Jerome White 《Formal Aspects of Computing》2011,23(5):649-679
This paper describes a methodology for developing and verifying a class of distributed systems in which the state space may
be discrete or continuous. Our focus is on systems where changes are local in that a small number of components change state
while the remainder of the system is unchanged. A proof methodology is developed that ensures global properties, such as invariants
and convergence, by guaranteeing local properties within subsystems. This methodology is used to prove the correctness of
concrete examples. We present a PVS library of theorems and proofs that can be used to reduce the work required to develop
and verify programs in this class. A transformation of these libraries to Java is also outlined. 相似文献
50.
Idoia Berges Jesús Bermúdez Alfredo Goñi Arantza Illarramendi 《Expert systems with applications》2013,40(7):2462-2475
Over the last years, there has been a change of perspective concerning the management of information systems, since they are no longer isolated and need to communicate with others. However, from a semantic point of view, real communication is difficult to achieve due to the heterogeneity of the systems. We present a proposal which, considering information systems are represented by software agents, provides a framework that favors a semantic communication among them, overcoming the heterogeneity of their agent communication languages. The main components of the framework are a suite of ontologies – conceptualizing communication acts – that will be used for generating the communication conversion, and an Event Calculus interpretation of the communications, which will be used for formalizing the notion of a satisfactory conversion. Moreover, we present a motivating example in order to complete the explanation of the whole picture. 相似文献