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101.
Abstract

This paper describes a database application generator for the WWW called GWB. GWB contains a compact language that adds control structures and database access constructs to HTML, a compiler that translates HTML‐like source templates into ODBC code and utilities for authentication and session management. It is designed to ease the expertise requirement needed for developing Web‐based intranet and internet database applications. This paper surveys the current approaches; describes the language and its support for authentication and session management; and gives an internet application using GWB. This paper also discusses future enhancement in terms of persistent database connections and server‐side client state persistency.  相似文献   
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This paper explores reclaimed and recycled material used in ecovillages. The models discussed in this paper include BedZED in the United Kingdom and Masdar City in the Middle East. These two communities contain features characterized by the sustainable principles of the ecovillage concept by using non-traditional building materials. The creations of more ecovillages, along with the growth of current ecovillages, play an important role in positively solvening environmental and social problems. The sustainable materials used in the ecovillages also act as a model for communities wishing to implement sustainable development.  相似文献   
104.
The effects of annealing atmosphere (N2, air and O2) on the electrical properties of sol–gel‐derived MgNb2O6/ITO heterostructures are discussed in this work. All samples exhibited the amorphous phase and were highly transparent. The percentage of Nb4+ content increased when the films were annealed in the oxygen‐deficient conditions, which could lead to semiconducting films. In addition, the results show that the electrical properties of sol–gel‐derived MgNb2O6 thin films could be tuned based on the annealing atmosphere. Moreover, the conduction mechanisms of MgNb2O6/ITO heterostructures are also discussed in this study. The results show that MgNb2O6 thin films have potential for use in multifunctional optoelectronic applications, due to their flexible electrical properties and good transparency.  相似文献   
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107.
(1) Background: Our aim is to reveal the influence of the geometry designs on biophysical stimuli and healing patterns. The design guidelines for dental implants can then be provided. (2) Methods: A two-dimensional axisymmetric finite element model was developed based on mechano-regulatory algorithm. The history of tissue differentiation around eight selected implants can be predicted. The performance of the implants was evaluated by bone area (BA), bone-implant contact (BIC); (3) Results: The predicted healing patterns have very good agreement with the experimental observation. Many features observed in literature, such as soft tissues covering on the bone-implant interface; crestal bone loss; the location of bone resorption bumps, were reproduced by the model and explained by analyzing the solid and fluid biophysical stimuli and (4) Conclusions: The results suggested the suitable depth, the steeper slope of the upper flanks, and flat roots of healing chambers can improve the bone ingrowth and osseointegration. The mechanism related to solid and fluid biophysical stimuli were revealed. In addition, the model developed here is efficient, accurate and ready to extend to any geometry of dental implants. It has potential to be used as a clinical application for instant prediction/evaluation of the performance of dental implants.  相似文献   
108.
The mechanical behavior of MoSi2 reinforced–Si3N4 matrix composites was investigated as a function of MoSi2 phase content, MoSi2 phase size, and amount of MgO densification aid for the Si3N4 phase. Coarse-phase MoSi2-Si3N4 composites exhibited higher room-temperature fracture toughness than fine-phase composites, reaching values >8 MP·am1/2. Composite fracture toughness levels increased at elevated temperature. Fine-phase composites were stronger and more creep resistant than coarse phase composites. Room-temperature strengths >1000 MPa and impression creep rates of ∼10−8 s−1 at 1200°C were observed. Increased MgO levels generally were deleterious to MoSi2-Si3N4 mechanical properties. Internal stresses due to MoSi2 and Si3N4 thermal expansion coefficient mismatch appeared to contribute to fracture toughening in MoSi2-Si3N4 composites.  相似文献   
109.
In this study, the effects of different oxygen‐containing group contents in thermally reduced graphene oxides (TRGs) for enhancing the physical properties of epoxy nancomposites was examined. The epoxy/TRG nanocomposites (ETNs) were prepared by a room temperature curing method in the presence of TRGs containing different oxygen‐containing groups and were then characterized by Fourier transform infrared spectroscopy. TRG contents with higher oxygen‐containing group contents (ca 33%) were found to show better dispersion capability in the epoxy matrix than TRGs with lower oxygen‐containing group contents (ca 11%) based on morphological observations by transmission electron microscopy. The better dispersion capability of TRGs with higher oxygen‐containing group contents in ETN membranes was found to lead to significantly enhanced mechanical strength, thermal stability and thermal conductivity based on measurements of dynamic mechanical analysis, tensile tests, thermogravimetric analysis and by the transient plane source technique. © 2014 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry  相似文献   
110.
Tsai LJ  Yu KC  Chen SF  Kung PY 《Water research》2003,37(10):2449-2457
The aim of this study was to determine the effect of temperature on the solubilization of heavy metals from contaminated river sediment by sulfur oxidizing bacteria taken from Ell-Ren River sediment. Of three temperatures tested (25 degrees C, 37 degrees C and 55 degrees C), pH decrease was greatest at 37 degrees C, indicating that, after acclimation, bacterial oxidizing activity is greatest at this temperature. At 55 degrees C, pH change was similar to that which occurred with no inoculum added. The increase in sulfates and high pH at 55 degrees C indicate that the indirect mechanism was not initiated at this temperature. Solubilization efficiency of total extractable Ni, Zn, Cu and Cr was high (>90%) at 37 degrees C, whilst that of Pb was only 60.4%. Except for Pb, the optimal temperature for solubilization of total extractable heavy metal was 37 degrees C. The order of average solubilization efficiency of total extractable heavy metals was Ni, Zn, Cu>Cr>Co, Pb. The solubilization efficiency of Pb and Co was markedly less than that of other heavy metals. Transfer of heavy metals between binding fractions was most apparent at 55 degrees C before and after bioleaching.  相似文献   
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