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181.
Akbar Zaman Ihsan Ihsanullah Anwarulhaq Ali Shah Tariq Nawaz Khattak Saeed Gul Imdad Ullah Muhammadzai 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(3):1665-1672
Gamma irradiation in combination with hot water dipping treatment was tested for maintaining storage quality and extending the shelf life of peach fruit. The matured peaches fruits (local variety no, Tex-A-6-69) were first dipped in hot water having temperature of 0, 40 and 60 °C for 60 seconds and they were exposed to 0.5 and 1.0 kGy doses of gamma radiation and stored in paper cartons under ambient (temperature 25 ± 2 °C, RH 70 %) conditions for their physico-chemical evaluations on weekly basis. The combine effect of hot water dipping treatment and irradiation for peach was study for the first time in Pakistan. The parameters studied included % weight loss, % ash content, % moisture content, total soluble solids (TSS), titratable acidity and ascorbic acid. The sensory indices studied were size, shape, color and overall acceptability. The sensory evaluation values at 0 days for the controlled peach sample were recorded for comparison. Statistical analysis was performed to find determinates of irradiation alone and in combination with hot water dipping techniques on peaches. Studies revealed that irradiation treatment in combination with hot water treatments significantly (LSD at 5 %) maintained the storage quality of peach fruit under ambient conditions. Data obtained for weight loss, moisture, shape and overall acceptability showed significant results while non-significant values were recorded for ash, TSS and size. Overall, consumers rated the acceptability of treated peaches higher than untreated peaches. This particular type of research also helps in improving one’s country export quality of fruits. 相似文献
182.
An efficient synthesis of some novel 2-aroylimino-3-aryl-4-phenyl-1,3-thiazolines was carried out by base-catalyzed cyclization of 1-aroyl-3-arylthioureas with acetophenone in the presence of bromine. The structures were confirmed by spectroscopic data, elemental analyses, and in one case (2t) by single-crystal X-ray diffraction data. 相似文献
183.
The synthesis of some novel alkyl/aryl substituted tertiary alcohols was accomplished in two steps. The synthetic route involves preparation of Grignard reagents by treating alkyl/aryl bromides with magnesium turnings in dry ether. Then substituted chalcones were reacted with the Grignard reagents to afford alkyl/aryl substituted tertiary alcohols 1-10. The structures of the synthesized compounds were assigned on the basis of FT-IR, 1H-NMR, 13C-NMR and mass spectroscopic data. The in vivo anti-inflammatory activity of the synthesized compounds was evaluated using the carrageenan-induced hind paw edema method and was compared with that of ibuprofen. Some of the newly synthesized compounds showed promising anti-inflammatory activity. The tertiary alcohols 1-10 were also screened for antibacterial activity against ten bacterial strains using seven Gram-positive and three Gram-negative bacteria and for antifungal activity against Aspergillus Flavus, Aspergillus Niger and Aspergillus pterus. Tertiary alcohols 1-10 were found to exhibit good to excellent antimicrobial activities compared to levofloxacin and fluconazole used as standard drugs. 相似文献
184.
Javeed Akhtar Naeema Khan Shahabuddin Memon Zaman Ashraf Ghulam Abbas M. Usman Anwar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1627-1638
New substituted and unsubstituted phenol based mesogene series having an azo central linkage was synthesized by fixing phenol as rigid core unit with aromatic amine. The terminal –OH group was esterified successively by long alkyl chain acid chloride of variable length (n=2, 6, 11, 15, 17). All 25 synthesized compounds exhibit mesomorphism. The effect of side chain length and substituents on the stability of liquid crystals was studied. The study reveals that nitro substituent destabilizes nematic and smectic phases more than floro substituent. Furthermore, the transition temperature decreases as the length of side chain increases. 相似文献
185.
H. Zaman T. Hayat M. Ayub R. S. R. Gorla 《Numerical Methods for Partial Differential Equations》2011,27(6):1511-1524
This work is concerned with the influence of uniform suction or injection on flow and heat transfer analysis of a second order fluid. The resulting nonlinear problem for velocity is solved by means of homotopy analysis method (HAM). The comparison between the numerical solution of Hady and Gorla (Acta Mec 128 (1998), 201–208 and HAM solution is discussed with the help of numerical tables and graphs. Nonsimilar solutions to the stream function and temperature are developed. The influence of important parameters is seen on the velocity, temperature, skin friction coefficient, and temperature gradient. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 1511–1524, 2011 相似文献
186.
Luther W. White
Musharraf Zaman
《Applied mathematics and computation》1998,90(2-3):181-203A porous media model is derived describing the accumulation and flow of fluid within a domain. The model consists of a differential expression determining the saturated fluid subdomain and a relation describing the pressure distribution within that domain. The wellposedness and numerical solution of a simplified problem is presented and a validation using field rainfall outflow data collected from a highway roadbed is discussed. 相似文献
187.
M. Saeed Arayne Najma Sultana M. Kamran Zaman 《Accreditation and quality assurance》2008,13(8):431-432
The concept of good manufacturing practice (GMP) is not new; its roots are very old. The incidents that gave birth to the
concept of GMP are summarized in this article. The journey from the FDA toward GMP is highlighted in chronological order.
These regulations are mandatory for pharmaceutical industries in order to manufacture quality products. 相似文献
188.
Benzene-1,3-diamidoethanethiol (BDETH2) is an exceptional precipitant for removing soft heavy metals from water. The present work will detail the bonding arrangement of BDETH2 to the metals Cd, Hg, and Pb, along with the full characterization data of the BDET-M compounds. It was found that the Hg compound has a linear S-M-S geometry. The characterization data consisted of Mp, EA, IR, Raman, MS, XANES, EXAFS, and solid-state multinuclear NMR. 相似文献
189.
Sabah E 《Journal of colloid and interface science》2007,310(1):1-7
The adsorption characteristics of acid activated sepiolite (AAS) for the removal of chlorophyll-a (C(55)H(72)MgN(4)O(5)) from rapeseed oil was studied as a function of different sepiolite dosages and bleaching temperatures. A correlation has been shown between the adsorption capacity and a combination of AAS amount, bleaching temperature and oxidative reactions of chlorophyll-a. The adsorption equilibrium was found to follow the Langmuir isotherm model with a maximum adsorption capacity of 0.36 mg/g on AAS and K(L) value ranging from 6.11 to 19.51 kg/mg at 80 and 100 degrees C. It was found that AAS is an effective sorbent for the removal of chlorophyll-a molecule which is believed to adsorb as a protonated species onto SiOH groups at the edge in the tetrahedral sheet of sepiolite. These findings reveal that chlorophyll-a molecules not only adsorb onto the external surface of AAS but replace the released Mg(2+) ions in the octahedral sheet; they, depending on the pore size of AAS, are also incorporated in the channels and tunnels of sepiolite. A structural model is proposed to account for the orientation of chlorophyll-a in the sepiolite matrix. 相似文献
190.
Rasim Batmaz Nishil Mohammed Masuduz Zaman Gagan Minhas Richard M. Berry Kam C. Tam 《Cellulose (London, England)》2014,21(3):1655-1665
Cellulose nanocrystals (CNCs) prepared from cellulose fibre via sulfuric acid hydrolysis was used as an adsorbent for the removal of methylene blue (MB) from aqueous solution. The effects of pH, adsorbent dosage, temperature, ionic strength, initial dye concentration were studied to optimize the conditions for the maximum adsorption of dye. Adsorption equilibrium data was fitted to both Langmuir and Freundlich isotherm models, where the Langmuir model better described the adsorption process. The maximum adsorption capacity was 118 mg dye/g CNC at 25 °C and pH 9. Calculated thermodynamic parameters, such as free energy change (ΔG = ?20.8 kJ/mol), enthalpy change (ΔH = ?3.45 kJ/mol), and entropy change (ΔS = 0.58 kJ/mol K) indicates that MB adsorption on CNCs is a spontaneous exothermic process. Tunability of the adsorption capacity by surface modification of CNCs was shown by oxidizing the primary hydroxyl groups on the CNC surface with TEMPO reagent and the adsorption capacity was increased from 118 to 769 mg dye/g CNC. 相似文献