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131.
Preparation and characterization of a series of ion‐exchange membranes for the purpose of separation and extraction of some heavy and toxic metal ions from their wastes were studied. Such ion‐exchange membranes were prepared by γ‐radiation grafting of acrylonitrile (AN) and vinyl acetate (VAc) in a binary monomer mixture onto low‐density polyethylene (LDPE) using the direct technique of grafting. The reaction conditions at which the grafting process proceeds successfully were determined. Many modification treatments were attempted for the prepared membranes to improve their ion‐exchange properties. The possibility of their practical use in waste‐water treatment to remove some heavy and toxic metal ions such as Pb2+, Cd 2+, Cu2+, Fe3+, Sr2+, and Li+ were investigated. These grafted membranes showed great promise for possible use in the field of extraction and removal of some heavy and toxic metals from their wastes. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 849–860, 2001  相似文献   
132.
This paper presents a tectonostratigraphic interpretation based on seismic, gravity and well data of the Upper Cambrian through Devonian sedimentary succession in the central part of the Darling Basin, New South Wales (SE Australia). A composite roughly north‐south trending 2D seismic section through this area, tied to two exploration wells, defines four unconformity‐bound second‐order seismic megasequences. The megasequences are: A, Upper Cambrian – Middle Ordovician (Llanvirnian?); B, uppermost Silurian – Lower Devonian (Emsian); C, upper Lower Devonian – lower Middle Devonian (Givetian); and D, upper Middle Devonian – Upper Devonian (Famennian). The megasequences are bounded by prominent seismic marker horizons which represent phases of regional‐scale orogenic activity. The composite 2D section studied is about 150 km long and traverses from north to south the Pondie Range sub‐basin, the inverted Wilcannia High and the Blantyre sub‐basin. Along the section, the Upper Cambrian to Devonian succession is deformed into a series of large‐scale, fault‐associated anticlines and synclines including the Avon High, an asymmetric anticlinal fold associated with several high‐angle reverse faults. Major faults extend into, and flatten within, the basement. The top‐basement surface is characterized by broad highs and lows which are represented on a gravity map of the study area. The map shows that the Wilcannia High defines the northern margin of the Blantyre sub‐basin and the southern margin of the Pondie Range sub‐basin. These sub‐basins are in general defined by gravity lows. The development of the Blantyre and Pondie Range sub‐basins can be divided into five tectonostratigraphic phases during which there were distinct patterns of fault activity and regional subsidence. These phases are investigated using a restoration model which involves the successive removal of each seismic megasequence in turn, assuming simple vertical shear. The model provides new constraints on the distribution of structural and stratigraphic features which are relevant for future hydrocarbon exploration.  相似文献   
133.
The present study reports the rheological, textural, structural and water distribution properties of fish meat noodles. The results showed that storage and loss modulus were increased when 20% fish meat was added while decreased with the addition of >20% fish meat, whereas loss rate behaved vice versa. The moisture and fat content increased significantly (P < 0.05) while water absorption index was decreased upon the increment of fish meat compared to control. Lightness of dough and hardness of noodles decreased significantly (P < 0.05) while redness and yellowness were increased. Similarly, less swelled starch granules and dominancy of protein network over starch granules were observed in microstructure. The amount of free water was increased while bound water was decreased when >20% fish meat was added during low-field nuclear magnetic resonance. The findings suggest the feasibility of adding 15–20% fish meat for the proper structure and chemistry of noodles.  相似文献   
134.
135.

The development of hardware platforms for artificial neural networks (ANN) has been hindered by the high consumption of power and hardware resources. In this paper, we present a methodology for ANN-optimized implementation, of a learning vector quantization (LVQ) type on a field-programmable gate array (FPGA) device. The aim was to provide an intelligent embedded system for real-time vigilance state classification of a subject from an analysis of the electroencephalogram signal. The present approach consists in applying the extension of the algorithm architecture adequacy (AAA) methodology with the arithmetic accuracy constraint, allowing the LVQ-optimized implementation on the FPGA. This extension improves the optimization phase of the AAA methodology by taking into account the operations wordlength required by applying and creating approximative-wordlength operation groups, where the operations in the same group will be performed with the same operator. This LVQ implementation will allow a considerable gain of circuit resources, power and maximum frequency while respecting the time and accuracy constraints. To validate our approach, the LVQ implementation has been tried for several network topologies on two Virtex devices. The accuracy–success rate relation has been studied and reported.

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136.
137.
Properties of concrete during and after fire exposure are of significant importance for serviceability and rehabilitation of buildings. This article presents an experimental investigation on the effects of elevated temperature on physical and mechanical properties of concrete made using two types of locally available coarse aggregates (crushed and wadi aggregates) and water‐to‐cement (w/c) ratios of 0.50 and 0.70. Temperature range from 200 °C to 1000 °C was used with intervals of 200 °C. Test results indicate that the weight of concrete reduced with increase in temperature. This reduction was quite sharp beyond 800 °C. Minor spalling was observed in concrete with Wadi aggregates at temperatures beyond 800 °C. The results also reveal that relative strength of concrete decreased as exposure temperature increased. The effect of high temperatures on the strength of concrete was more pronounced in concrete with Wadi aggregates. w/c ratio had insignificant effect on weight loss after exposure to elevated temperatures, but it increased the rate of strength degradation irrespective of aggregate type used. Comparison of results with Eurocode (EC‐2) and American Concrete Institute (ACI) standards indicate that the concrete with both aggregate types can satisfy the limits of siliceous aggregates set by ACI, but concrete made with Wadi aggregates with w/c ratio of 0.50 failed to satisfy limits of EC‐2. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
138.
New aryl substituted 8-hydroxyquinoline derivatives have been synthesized. The compounds were characterized by 1H, 13C-NMR spectroscopy and mass spectrometry. The aluminum complexes of these derivatives show strong green emission in the range 530-535 nm with high quantum yield compared to the parent tris (8-hydroxyquinolinato)aluminum(III) complex. The structure of the aryl-substituted 8-hydroxyquinoline aluminum complexes in the ground state have been optimized at the B3LYP/6-31G* level of theory. The parent 8-hydroxyquinoline has also been examined using this method with the same basis set. A clear correlation between the shortening of the Al-N bond and red shift in the fluorescence emission band was observed. We have also found that substitution at the 5 and 7 position of the 8-hydroxyquinoline ligand cause simultaneous energy lowering of both highest occupied molecular orbital and the lowest unoccupied molecular orbital with the 5, 7-aryl substituted derivatives exhibiting the greatest effect.  相似文献   
139.
The main purpose of this paper is to propose several new maintenance policies that can be performed at suitable middle times for trivariate preventive maintenance scenarios. Firstly, characteristics and limitations for the approaches of whichever occurs first and whichever occurs last are analyzed, and their respective maintenance models, which are called first maintenance and last maintenance, are given directly. Secondly, a combined approach of first and last is employed and middle maintenance is proposed. Thirdly, the aforementioned policy is modified to be performed at discrete working cycles, using the method of overtime maintenance. Finally, a new approach of whichever occurs middle is proposed for modelings. We give the analyses of how to formulate the middle maintenances and obtain their expected maintenance cost rates, using the technique of cumulative damage models. Numerical examples are given to compare the optimal policies among first, last, and middle maintenances. Finally, a potential application of middle maintenance is provided for future studies. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
140.
Propolis, a honey bee product, has been used in folk medicine for centuries for the treatment of abscesses, canker sores and for wound healing. Caffeic acid phenethyl ester (CAPE) is one of the most extensively investigated active components of propolis which possess many biological activities, including antibacterial, antiviral, antioxidant, anti-inflammatory, and anti-cancer effects. CAPE is a polyphenolic compound characterized by potent antioxidant and cytoprotective activities and protective effects against ischemia–reperfusion (I/R)-induced injury in multiple tissues such as brain, retina, heart, skeletal muscles, testis, ovaries, intestine, colon, and liver. Furthermore, several studies indicated the protective effects of CAPE against chemotherapy-induced adverse drug reactions (ADRs) including several antibiotics (streptomycin, vancomycin, isoniazid, ethambutol) and chemotherapeutic agents (mitomycin, doxorubicin, cisplatin, methotrexate). Due to the broad spectrum of pharmacological activities of CAPE, this review makes a special focus on the recently published data about CAPE antioxidant activity as well as its protective effects against I/R-induced injury and many adverse drug reactions.  相似文献   
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