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41.
The present study focused on dyeing, fastness, cytotoxic properties, and phenolic constituents of various types of fabrics including viscose, cotton, wool, and polyester-viscose blended fabrics with different parts of Anthemis tinctoria var. tinctoria. Comparative study was carried out between ethanol and aqueous extracts of stem, flower, and root of the plant in terms of phenolic constituents, cytotoxic activity, and dyeing properties. It was found that the quantity of phenolic constituents of ethanol and aqueous extracts was quite different. All parts of the plant extract show 0% cytotoxicity except ethanol extract of the root. All the extracts exhibit better cytotoxic activity than the standard cancer drug 5-Florouracil. Ethanol and water extracts of A. tinctoria var. tinctoria plant were used to dye fabrics, but only the water extract displayed dyeing properties. Best color strength value (K/S = 9.19) was obtained with aqueous extract of the stem in the presence of alum mordant for cotton fabrics. 相似文献
42.
Modifying of Cotton Fabric Surface with Nano-ZnO Multilayer Films by Layer-by-Layer Deposition Method 总被引:1,自引:0,他引:1
Şule S Uğur Merih Sarıışık A Hakan Aktaş M Çiğdem Uçar Emre Erden 《Nanoscale research letters》2010,5(7):1204-1210
ZnO nanoparticle–based multilayer nanocomposite films were fabricated on cationized woven cotton fabrics via layer-by-layer
molecular self-assembly technique. For cationic surface charge, cotton fabrics were pretreated with 2,3-epoxypropyltrimethylammonium
chloride (EP3MAC) by pad-batch method. XPS and SEM were used to examine the deposited nano-ZnO multilayer films on the cotton
fabrics. The nano-ZnO films deposited on cotton fabrics exhibited excellent antimicrobial activity against Staphylococcus aureus bacteria. The results also showed that the coated fabrics with nano-ZnO multilayer films enhanced the protection of cotton
fabrics from UV radiation. Physical tests (tensile strength of weft and warp yarns, air permeability and whiteness values)
were performed on the fabrics before and after the treatment with ZnO nanoparticles to evaluate the effect of layer-by-layer
(LbL) process on cotton fabrics properties. 相似文献
43.
Mehmet Aydın Hüseyin Sevgili Bekir Tufan Yilmaz Emre Sevim Köse 《International Journal of Food Science & Technology》2011,46(3):500-508
Proximate composition and fatty acid (FA) profile of three commercial sea cucumbers; Holothuria tubulosa, Holothuria polii and Holothuria mammata caught from Aegean Sea of Turkey were analysed. The effects of regional variation and drying process on FA composition were also investigated. Moisture, protein, fat and ash contents of the species ranged between 81.24% and 85.24%, 7.88% and 8.82%, 0.09% and 0.18%, and 5.13% and 7.85%, respectively, with a significant changes among species (P < 0.05) with some exceptions. Although FA values varied significantly (P < 0.05) among species and regions, the changes for most FA types representing the same region for different species were not significantly different. Total polyunsaturated fatty acids (PUFA) were found to be higher than total saturated (SFA) and monosaturated FAs (MUFA) accounting for 53.0–62.12% for ∑PUFA, 13.28–16.41% for ∑MUFA and 13.99–19.21% for ∑SFA. While some individual SFAs and PUFAs decreased after drying process, various individual FAs of MUFA increased in their amounts (P < 0.05). Among PUFAs, the highest mean value of eicosapentaenoic acid and docosahexaenoic acid for all regions were determined for H. polii as 7.25% and H. tubulosa as 12.37% in fresh samples, respectively. This study represents new information relating to FA contents and drying effect on FA profile for these species. 相似文献
44.
The present work investigates gold recovery using DEAE-cellulose, a common biopolymer derivative, from synthetically prepared diluted gold-bearing solutions of 50 ppm. The effects of different recovery parameters on gold recovery efficiency were studied in detail. It was demonstrated that gold recovery efficiency increased with an increasing amount of sorbent, as well as increasing contact time. A gold recovery efficiency of 99% was attained under conditions of 20–40 g DEAE-cellulose per liter at a shaking rate of 130 rpm for 30 min at room temperature. On the other hand, with smaller amounts of sorbent (6 g/l), it was also possible to recover gold from the solution with 99% efficiency when the reaction temperature was increased to 60 °C. The shaking rate and temperature were demonstrated to play a vital role in the recovery process. It was also found that gold recovery by DEAE-cellulose is an intermediate-controlled process with an activation energy of 37.11 kJ/mol. The XRD pattern and SEM images revealed that the recovered gold was in the metallic form. 相似文献
45.
Tevfik Tozkoparan Emre Ulas Macit Olcer Cavit Arikan Meric Batmaz Aylin Saracoglu Goknur Murat Ozyilmaz Sevgi Kayhan Ebru Soydas Izmir Branch Archives Noyan Sancar Mehmet Yasa Guven Incirlioglu 李璠 《世界建筑》2010,(7):26-31
<正>一座建筑的性能应当如何来衡量?除了通过统治当代建筑舆论的美学、技术以及经济价值来进行描述之外,我们还能够如何来阐释一座建筑,尤其是一座致力于庇护那些渴望展现自己的艺术家的建筑?有人会问成功的表演是如何实现的,表演者是如何进行伪装的、又是如何展现自己的?根据海德格尔的理论,当我们看不到钉子的时候,铁锤的表现才是成功的;钉子本身的出现通常表明出现了问题。 相似文献
46.
47.
Leadership in Energy and Environmental Design (LEED) is a certification program developed by the U.S. Green Building Council for designing, constructing, and certifying green buildings. This paper presents a LEED implementation guide for construction practitioners to assist them in the certification process. The guide was formulated primarily through input, suggestions, and recommendations received from LEED accredited professionals including architects, engineers, commissioning authorities, general contractors, construction managers, and facility managers. Data were collected through four questionnaire surveys where two of which were used for guide development and the other two for modification and validation. General contractors, construction managers, and engineers can use the LEED implementation guide as a reference for managing their LEED certification process. The proposed guide can also assist owners interested in building a LEED certified facility. 相似文献
48.
Suphi S. Oncel Esra Imamoglu Emre Gunerken Fazilet Vardar Sukan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(3):414-420
BACKGROUND: Recent studies indicate that microalgal cultivation using organic carbon sources has the potential to provide high yields. Haematococcus pluvialis and Chlorella zofingiensis, two important carotenoid producers, were selected for co‐culture cultivations to utilize the unique advantages of both organisms. A co‐culture production process was investigated in terms of the effects of organic carbon source, co‐cultivation method, and light intensity on carotenoid production. RESULTS: The addition of 5 g L?1 glucose resulted in a growth rate of 0.60 day?1 for H. pluvialis and 0.59 day?1 for C. zofingiensis, which were higher than those for other carbon sources tested and the control group. Incremental increase of light intensity instead of direct increase to 170 µE m?2s? prevented cell loss in both cultures. Co‐cultivation based on cell numbers (60% H. pluvialis and 40% C. zofingiensis) prevented population domination of one microalgae over the other. The biomass production rate of the co‐culture was higher (0.61 g L?1 day?1) in glucose‐enriched medium. The total carotenoid content of the co‐culture in the control culture was higher (0.83 mg total carotenoids g?1 cell) than that obtained in glucose‐enriched medium (0.54 mg total carotenoids g?1 cell) but not as high as the amounts reached in mono‐cultures. CONCLUSION: Total carotenoid content of the mono‐cultures gave higher yields in standard bold basal medium (BBM). Preliminary high performance liquid chromatography (HPLC) studies indicated a variation in the amounts of astaxanthin isomers produced. Further studies are in progress to determine the effects of carbon‐enriched media and co‐cultivation on the type of isomers and caretenoids produced. Copyright © 2010 Society of Chemical Industry 相似文献
49.
Emre Cevikcan M. Bulent Durmusoglu Murat E. Unal 《Computers & Industrial Engineering》2009,56(2):576-599
Team-oriented approaches are widely being used in modern real life assembly systems, as are other modern systems. In this paper, first the literature of single and mixed model assembly line balancing, which plays an important role for the design of assembly systems, is reviewed. The associated literature matrixes reveal that team-oriented approaches do not have an intensive research area. Second, a team-oriented mathematical programming model for creating assembly teams (physical stations) in mixed model assembly lines is devised. Owing to the fact that this model is NP hard, a scheduling based heuristic algorithm is developed. The mixed model assembly line design methodology, which includes a team-oriented algorithm as a step, is proposed. Both model sequencing and worker transfer systems are included in the methodology. The algorithms for each step of the methodology are also coded by using MATLAB and MS Excel is used as the user interface. Furthermore, the presented methodology was applied in a chosen segment of a real life mixed model tractor assembly system. 相似文献
50.
Optimal space-frequency Group codes for MIMO-OFDM system 总被引:2,自引:0,他引:2
Space-frequency (SF) group codes are designed for multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems. A rather general channel model is assumed, where the channel is frequency-selective Rayleigh fading with arbitrary power-delay profile. It is shown that the SF group code has a symmetric distance structure like the space-time group code, if the group consists of diagonal matrices. A scenario where the multiple codewords are loaded onto the subcarriers of the OFDM system in parallel is considered. The optimality condition on the choice of subcarrier allocation is found, and an optimal subcarrier-allocation scheme is proposed. A transmit scheme where rotated versions of the same signal are transmitted from different transmit antennas is proposed, and it is shown that it satisfies the optimality condition. Then matrix groups are designed which guarantee that the resulting SF codes are full rank. Numerical comparisons with recently published techniques in the literature verify our improved performance. 相似文献