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41.
Hadi Zamanifard Tooran Alizadeh Caryl Bosman Eddo Coiacetto 《Journal of Urban Design》2019,24(3):340-364
This paper presents an index for measuring experiential qualities (EQs) of urban public spaces through users’ perspective. The index is underpinned by interrelated qualities of comfort, diversity and vitality, inclusiveness, and image and likeability. It is then applied to two public spaces in the Australian city of Brisbane: Queen Street Mall and South Bank Parklands. The index extends the user-centred measuring tools and can be used by practitioners, authorities and scholars to highlight users’ needs and concerns. Findings from case spaces revealed deficiencies and provided a deeper insight into EQs through integrating urban design qualities, perception and management measuring items. 相似文献
42.
Mahdi Mubarok Yusuf Sudo Hadi Jajang Suryana Wayan Darmawan Frédéric Simon Stéphane Dumarcay Christine Gérardin Philippe Gérardin 《Holz als Roh- und Werkstoff》2017,75(6):877-884
Evaluation of commercially available polyurethane resins used up to now for coating applications to develop non-biocidal wood preservation treatments has been conducted. A simple method of vacuum impregnation of these resins into beech wood (Fagus sylvatica L.) and pine wood (Pinus sylvestris L.) samples followed by varied curing processes at ambient temperature, 103, and 200 °C has been performed. Based on the analysis of weight percent gain before and after leaching, treatment resistance to leaching, anti-swelling efficiency, wettability and decay durability measured for treated and untreated blocks after leaching with the white-rot fungus Coriolus versicolor for both wood species and the brown-rot fungi Poria placenta and Gloeophyllum trabeum for pine wood, it can be concluded that such treatment can be considered as potential valuable non-biocidal treatments. 相似文献
43.
Hadi Haeri ;Kourosh Shahriar ;Mohammad Fatehi Marji ;Parviz Moarefvand 《中南工业大学学报(英文版)》2014,(6):2404-2414
The mechanism of cracks propagation and cracks coalescence due to compressive loading of the brittle substances containing pre-existing cracks (flaws) was modeled experimentally using specially made rock-like specimens from Portland Pozzolana Cement (PPC). The breakage process of the specimens was studied by inserting single and double flaws with different inclination angles at the center and applying uniaxial compressive stress at both ends of the specimen. The first crack was oriented at 50° from the horizontal direction and kept constant throughout the analysis while the orientation of the second crack was changed. It is experimentally observed that the wing cracks are produced at the first stage of loading and start their propagation toward the direction of uniaxial compressive loading. The secondary cracks may also be produced in form of quasi-coplanar and/or oblique cracks in a stable manner. The secondary cracks may eventually continue their propagation in the direction of maximum principle stress. These experimental works were also simulated numerically by a modified higher order displacement discontinuity method and the cracks propagation and cracks coalescence were studied based on Mode I and Mode II stress intensity factors (SIFs). It is concluded that the wing cracks initiation stresses for the specimens change from 11.3 to 14.1 MPain the case of numerical simulations and from 7.3 to 13.8 MPa in the case of experimental works. It is observed that cracks coalescence stresses change from 21.8 to 25.3 MPa and from 19.5 to 21.8 MPa in the numerical and experimental analyses, respectively. Comparing some of the numerical and experimental results with those recently cited in the literature validates the results obtained by the proposed study. Finally, a numerical simulation was accomplished to study the effect of confining pressure on the crack propagation process, showing that the SIFs increase and the crack initiation angles change in this case. 相似文献
44.
In this paper we have presented a TOPSIS approach based on preference ratio and an efficient fuzzy distance measurement for a Fuzzy Multiple Criteria Group Decision-Making Problem (FMCGDMP). Preference ratio with a moderate modification for negative fuzzy numbers was used as an efficient ranking method for fuzzy numbers in a relative manner. As human reasoning persuades that distances between two fuzzy numbers should be a fuzzy measure, so all distances between fuzzy numbers (i.e. distances between alternatives, Fuzzy Positive Ideal solutions, and Fuzzy Negative Ideal solutions) have been calculated as fuzzy numbers using an efficient fuzzy distance measurement. The aforementioned arguments make the proposed algorithm unique and well posed for real-life problem modeling. Moreover, the main novelties of the proposed procedure (i.e. the fuzzy distance measurement and Preference Ratio) have been developed for Generalized Fuzzy Numbers (GFNs). The proposed algorithm has efficiently been applied in assessment of traffic police centers which is treated as a FMCGDMP. 相似文献
45.
Mohammad Reza Saeb Hadi Ramezani‐Dakhel Hossein Ali Khonakdar Gert Heinrich Udo Wagenknecht 《应用聚合物科学杂志》2013,127(6):4241-4250
After‐hatching eggshell (AHES) nanobiofiller and nanocalcium carbonate (nano‐CA) were separately added to various elastomers, such as acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), and natural rubber (NR), in various amounts of 5, 10, and 15 phr. The effect of particle size and dispersion of such nanofillers on thermomechanical properties and curing characteristics were then investigated. The ultimate tensile properties of SBR and NR nanocomposites were improved to some extent when 5 phr of AHES nanofiller was added to the rubber compound compared to CA. In the case of NBR nanocompounds, however, the mechanical properties were seemingly comparable, irrespective of the type of nanofiller. This contradictive behavior could be attributed to the alteration of crosslink density due to particular filler–matrix interaction while using mineral and natural fillers. The results of the rheometric study revealed that using AHES rather than CA slightly increases the scorch time of all types of prepared nanocomposites, whereas a significant drop in the optimum curing time was seen for NBR nanocomposites containing AHES biofiller. Moreover, thermogravimetric analysis showed similar thermal stability for SBR nanocomposites containing AHES and CA fillers. Finer particle size of CA and higher porosity of AHES at high and low loading levels were respectively the main reasons for improvement of ultimate properties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
46.
Seyed Morteza Mostashari Mohammad Ali Zanjanchi Hadi Fallah Moafi Seyedeh Zahra Mostashari Mohammad Reza Babaei Chaijan 《Polymer-Plastics Technology and Engineering》2013,52(3):307-312
We have investigated the effect of synthetic struvite (MgNH4PO4·6H2o) on the flammability of a cellulosic fabric. It was synthesized by means of the multiple-bath method and deposited onto a cotton fabric. Its uniformity was ensured by means of squeeze rolls, obtaining the optimum effective add-on value of ammonium magnesium phosphate to impart flame retardancy to cotton fabric in the range of around 12 g anhydrous salt per 100 g fabric. A thermogravimetric analysis of pure cotton, treated cotton, and the salt was accomplished, and their thermograms were compared and commented upon. The results obtained fortified the chemical theory expressing the promotion of the formation of solid char rather than the formation of volatile pyrolysis products, during the fulfillment of thermal decomposition of the cellulosic substrate. 相似文献
47.
Hadi Noori Mukesh Jain Kent Nielsen Frank Brandys 《Journal of Adhesion Science and Technology》2013,27(13):1403-1413
The peel resistance of adhesively bonded polymer films to a stainless steel sheet substrate (SSSS) with different engineered surface characteristics was examined in two different loading directions and for two different peel speeds. The SSSS was laminated with two thin polymeric adherends using two different pressure-sensitive adhesives. The SSSS surface was altered by grinding and knurling techniques before lamination and the effects of surface alterations on peel resistance were compared with peel resistance of the adherend from as-received SSSS with a bright annealed surface condition. For ground surface, an increase in adherend peel resistance was observed and the increase was attributed to increase in contact area between the adhesive and SSSS surface. For knurled surfaces which involved deeper and less frequent grooves, however, a decrease in peel resistance was observed. This was attributed to a more complex stress state at the peel front in the SSSS groove region during peeling. An increase in peel speed enhanced the peel resistance from both ground and knurled surfaces. 相似文献
48.
Silver nanowire transparent electrodes have received much attention as a replacement for indium tin oxide, particularly in organic solar cells. In this paper, we show that when silver nanowire electrodes conduct current at levels encountered in organic solar cells, the electrodes can fail in as little as 2 days. Electrode failure is caused by Joule heating which causes the nanowires to breakup and thus create an electrical discontinuity in the nanowire film. More heat is created, and thus failure occurs sooner, in more resistive electrodes and at higher current densities. Suggestions to improve the stability of silver nanowire electrodes are given. 相似文献
49.
Majid Ghashang Hadi Taghrir Mohammad Najafi Biregan Negar Heydari Fateme Azimi 《Journal of Sulfur Chemistry》2016,37(1):61-69
An eco-friendly procedure for synthesis of 2-(2-oxo-2H-chromen-4-yl)-3-arylthiazolidin-4-one derivatives by three-component reaction of 2-oxo-2H-chromene-4-carbaldehydes, aromatic amines and thioglycolic acid, with tetramethylbutane-1,4-diammonium acetate as a low-cost ionic liquid catalyst under reflux condition is described. The use of an ionic liquid as a catalyst has the advantages of high yields, short reaction time and environmentally friendly reaction media. 相似文献
50.
Zarrin Es’haghi Maryam Khalili Ali Khazaeifar Gholam Hossein Rounaghi 《Electrochimica acta》2011,56(9):52
In the present work, a novel solid phase microextraction (SPME) technique using a hollow fiber-supported sol–gel combined with multi-walled carbon nanotubes, coupled with differential pulse anodic stripping voltammetry (DPASV) was employed in the simultaneous extraction and determination of lead, cadmium and copper in rice. In this technique, an innovative solid sorbent containing mixture of carbon nanotube and a composite microporous compound was developed by the sol–gel method via the reaction of tetraethylorthosilicate (TEOS) with 2-amino-2-hydroxymethyl-propane-1,3-diol (TRIS). The growth process was initiated in basic condition (pH 10–11). Afterward this sol was injected into a polypropylene hollow fiber segment for in situ gelation process. The main factors influencing the pre-concentration and extraction of the metal ions; pH of the aqueous feed solution, extraction time, aqueous feed volume, agitation speed, the role of carbon nanotube reinforcement (as-grown and functionalized MWCNT) and salting effect have been examined in detail. Under the optimized conditions, linear calibration curves were established for the concentration of Cd(II), Pb(II) and Cu(II) in the range of 0.05–500, 0.05–500 and 0.01–100 ng mL−1, respectively. Detection limits obtained in this way are, 0.01, 0.025 and 0.0073 ng mL−1 for Cd(II), Pb(II) and Cu(II), respectively. The relative standard deviations (RSDs) were found to be less than 5% (n = 5, conc.: 1.0 ng mL−1). 相似文献