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11.
Kashif Iqbal Asfandyar Khan Danmei Sun Munir Ashraf Abdur Rehman Faiza Safdar 《纺织学会志》2019,110(4):625-638
Phase change materials (PCMs) are widely being used in thermal energy storage systems for solar engineering, building materials, heat pumps, spacecraft, and in textile field especially smart and technical textiles. There are large numbers of organic and inorganic PCMs that possess a wide range of melting and solidifying temperature which attracts researcher’s attention for their applications in different fields. This review paper summarizes the investigation and analysis of the available organic and inorganic PCMs, different encapsulating techniques, characterization techniques, incorporation into fiber and pad application on textiles with practical applications in the field of smart textiles. 相似文献
12.
Mohsin Ahmad Khan Nadia Hassan Nadeem Ahmad Muhammad Islam Khan Ahmad Usman Zafar Faidad Khan Tayyab Husnain 《Yeast (Chichester, England)》2014,31(1):13-28
Human interferon α2b (hIFNα2b) is the most important member of the interferon family. Escherichia coli, yeasts, mammalian cell cultures and baculovirus‐infected insect cells have been used for expressing recombinant human interferon. Recently a Pichia pastoris‐based expression system has emerged as an attractive system for producing functional human recombinant IFNα2b. In this regard, gene dosage is considered an important factor in obtaining the optimum expression of recombinant protein, which may vary from one protein to another. In the present study we have shown the effect of IFNα2b gene dosage on extracellular expression of IFNα2b recombinant protein from P. pastoris. Constructs containing from one to five repeats of IFNα2b‐expressing cassettes were created via an in vitro multimerization approach. P. pastoris host strain X‐33 was transformed using these expression cassettes. Groups of P. pastoris clones transformed with different copies of the IFNα2b expression cassette were screened for intrachromosomal integration. The IFNα2b expression level of stable transformants was checked. The copy number of integrated IFNα2b was determined by performing qPCR of genomic DNA of recombinant P. patoris clones. It was observed that an increase in copy number generally had a positive effect on the expression level of IFNα2b protein. Regarding the performance of multicopy strains, those obtained from transformation of multicopy vectors showed relatively high expression, compared to those generated using transformation vector having only one copy of IFNα2b. It was also observed that an increase in drug resistance of a clone did not guarantee its high expression, as integration of a marker gene did not always correlate with integration of the gene of interest. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
13.
Jasim Ahmed Mehrajfatema Zafar Mulla Yasir Ali Arfat 《International Journal of Food Properties》2017,20(8):1829-1842
Effect of high-pressure treatment (300–600 MPa) and flour-to-water ratio (1:1, 1:2, 1:3, and 1:4) on functional, rheological, thermal, and structural properties of whole wheat flour dough were investigated. The particle size distribution, especially Dv90 (90% of the volume distribution), was significantly reduced by the pressure treatment. The damaged starch content increased significantly with the applied pressure and water content. The damaged starch absorbed more water, and subsequently increased the water holding capacity. Thermal transitions and mechanical property of pressure-treated samples were measured by differential scanning calorimetry, and rheometry, respectively. The peak viscosity, hot paste viscosity, and final viscosity decreased significantly with increasing pressure intensity. Hardness increased with the increasing pressure level while stickiness decreased at similar conditions. Fourier-transform infrared spectroscopy showed changes in the amide I region of the wheat protein. The sodium dodecyl sulfate polyacrylamide gel electrophoresis further indicated changes in the protein subunits that occurred after pressurization. 相似文献
14.
Madhava Naidu Madineni Sheema Faiza Ragu Sai Surekha Ramasamy Ravi Manisha Guha 《Food science and biotechnology》2012,21(3):747-752
Starch isolated from maranta (Maranta arundinacea) tuber and studied for its various physicochemical characteristics. The amylose content of the starch was 24.8%. SEM showed that the granules were small indented and spherical. Maranta starch granule size has a range of 2.92–6.42 μm, (mean of 4.84 μm), length/degree of 1.20, and roundness of 0.73. Maranta starch has a gelatinization temperature of 74.8°C, peak viscosity of 498 BU, and cold paste viscosity of 669 BU. It also possessed higher freeze-thaw stability. Dynamic rheological properties of maranta starch, measured using parallel plate geometry showed increased storage modulus (G’) values, while loss modulus (G″) values were decreased with increasing frequency values (0–100 Hz). The low gelatinization temperature and high freeze thaw stability of starch indicates its potential for application as a thickener in food industries. 相似文献
15.
Mohamed H. Abd El‐Salam Arnold R. Hippen Kawther El‐Shafie Faiza M. Assem Hyam Abbas Mahmoud Abd El‐Aziz Osama Sharaf Mostafa El‐Aassar 《International Journal of Food Science & Technology》2011,46(10):2103-2110
Milk of high conjugated linoleic acid (CLA) level (1.25 g per 100 g milk fat) was produced by inclusion of fish oil and rousted soy bean in the ration of Holstein cows as compared to 0.55 g per 100 g milk fat in the milk of animals receiving control diet. Milk of normal (control) and high CLA content (treatment) was spray‐dried. Labneh was made from 20 g L?1 reconstituted milk using 3 mL per 100 mL yoghurt starter and 2 mL per 100 mL of probiotic cultures of Lactobacillus casei or Lactobacillus acidophilus. The control (C) and high CLA (T) labneh were analysed chemically and microbiologically, and their viscosities were determined during cold storage for 15 days. The fat content of labneh of high CLA was less than that of the control, but the total solids (TS) were unaffected by the CLA level. Labneh made with Lb. acidophilus had lower TS and higher acidity, exopolysaccharides and acetaldehyde contents and viscosity than that made with the use of Lb. casei. Labneh from the different treatments retained high counts of the added probiotic (>108 cfu g?1) throughout the storage period. The storage period had significant effects on all parameters determined. 相似文献
16.
Ambient‐cured polyesteramide (APEA) coating resin synthesized from dihydroxy fatty amide obtained from linseed oil, a sustainable resource, and poly(styrene‐co‐maleic anhydride), a bifunctional acid component, was found to exhibit improved physicomechanical and anticorrosive properties. The structural elucidation of APEA resin has been carried out by FTIR, 1H‐NMR, and 13C‐NMR spectroscopies. The physicomechanical and chemical resistance properties were investigated by standard methods. The corrosion resistance performance was evaluated in acid, alkali, and organic solvent. The thermal behavior was studied by TGA technique. A comparative study of these properties of APEA with reported baked polyesteramide (PEA) coatings was carried out. A remarkable improvement in the drying property of APEA was observed. The APEA coatings also showed improved physicomechanical and anticorrosive properties as compared to the baked PEA coatings. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1818–1824, 2005 相似文献
17.
Mohammad Kashif Eram Sharmin Fahmina Zafar Sharif Ahmad 《Journal of the American Oil Chemists' Society》2011,88(12):1989-1996
Ricinus communis (RC) oil-based materials are currently receiving increasing attention because of economic and environmental concerns. In
the present work, RC oil—a natural triol has been utilized for the development of an advanced polymeric material—poly(urethane-ricinoleamide)
(PUR) through very simple synthesis and curing strategy, omitting derivatization steps or side reactions, chain extenders
and crosslinkers. The synthesis of PUR was carried out in two steps. The first step is the introduction of an amide group
in the RC oil (89.5% ricinoleic acid) via base catalyzed amidation, which results in N, N-bis (2-hydroxyethyl) ricinoleamide (HERA). The second step is urethanation of HERA by the reaction of toluene-2,4-diisocyanate
(TDI) in minimal possible organic solvent by one-shot technique, which results in the formation of polyurethane along with
amide linkages. The physico-chemical and spectral studies (FT-IR, 1H-NMR and 13C-NMR techniques) confirm these two reactions and the structure of PUR. The resin was cured at ambient temperature without
any cross linker. Solubility of the resin was investigated in different polar and non-polar solvents. Thermo-gravimetric analysis
(TGA)/differential thermal analysis (DTA) and Differential Scanning Calorimetry (DSC) were used to determine the thermal stability
and curing behavior of PUR. An ambient cured ricinoleamide modified polyurethane resin exhibited thermal resistance up to
200–220 °C. 相似文献
18.
Haq Nawaz Nadia Zafar Raheela Jabeen Adnan Amjad Mohibullah Shah Saba Munir 《European Journal of Lipid Science and Technology》2023,125(11):2300053
The repeated use of cooking oils and ghee for the deep frying of food materials may affect their nutritional quality. The present study evaluated the effect of repeated frying on the physicochemical characteristics and antiradical potential of canola oil and ghee. The oil and ghee were used for frying of fish and chicken for 2, 4, 6, 8, and 10 frying cycles followed by the analysis of physicochemical, oxidative stress, and antiradical parameters. Regression analysis of the data showed a frying cycle-dependent significant linear increase in saponification (R2 = 0.9507–0.9748), peroxide and acid values (R2 = 0.956–0.9915), and malondialdehyde (MDA) production (R2 = 0.9058–0.9557) of canola oil and ghee subjected to fish and chicken frying but exponential increase in saponification value (R2 = 0.9778) and MDA production (R2 = 0.7407) of canola oil and ghee used for fish frying. The increase in the number of frying cycles linearly decreased the iodine value (R2 = 0.9781–0.9924), and 1, 1-diphenyl-2-picrylhydrazyl, hydroxyl, and 2, 2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical scavenging potential (R2 = 0.9089–0.9979) of canola oil and ghee. Repeated frying in cooking oil and ghee increases oxidative stress and decreases their physicochemical and antioxidant qualities. Canola oil was comparatively more oxidative resistant than canola ghee. The regression equations derived from regression analysis will guide researchers to conduct similar types of univariate studies. 相似文献
19.
Fahmina Zafar Hina Zafar Eram Sharmin S. M. Ashraf Sharif Ahmad 《Journal of Inorganic and Organometallic Polymers and Materials》2011,21(3):646-654
In this paper linseed oil based metallopolyesteramides (Mn(II)-/Co(II)-/Cu(II)-LPEA) containing metals [with half filled (d
5) and partially filled (d
7 and d
9) d orbitals] were synthesized via green route for the application of eco-friendly protective green material. This paper also
described the role of occupancy of d orbitals on the performance of such polymers. The synthesis reaction was carried out in situ through condensation polymerization
among linseed fatty amide diol (HELA), phthalic anhydride and respective metal acetates [M (OCOCH3)2; M = Mn(II), Co(II), Cu(II); different mole ratios] in absence of any harmful organic solvent. The structural determination
(FTIR, 1H-NMR and 13C-NMR), curing, thermal, physico-chemical, physico-mechanical, anticorrosive/chemical resistance, antibacterial properties
of Mn(II)-/Co(II)-/Cu(II)-LPEA were carried out. The curing mechanism of the resin was confirmed by the comparison of FTIR
spectra of uncured and cured resin. The curing mechanism of Mn(II)-/Co(II)-/Cu(II)-LPEA is found to be contrary to that of
reported oil based polymer that involves the lipid autoxidation (slow process) in which driers are required to speed up the
room temperature curing process. The incorporation of metals in Mn(II)-/Co(II)-/Cu(II)-LPEA improved the thermal stability
as compared to virgin linseed oil based polyesteramide (LPEA). Mn(II)-/Co(II)-/Cu(II)-LPEA also show excellent antibacterial
performance against Staphylococcus aureus and Escherichia coli. The observed diversity in material properties suggests that Mn-LPEA may be useful as an eco-friendly protective green material
with thermal stability up to 320–330 °C. 相似文献
20.