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101.
Tartrazine dye Na3TZ in foodstuff products was determined by a new modified carbon paste electrode, encoded sensor A, and a coated silver wire electrode, encoded sensor B, based on tartrazine TZ- cetryltrimethyl ammoniumbromide CTAB as a chemical modifier TZ-CTA. The electrodes exhibit the following characteristics listed respectively: a Nernstian slope of 17.9 ± 0.5 and 19.4 ± 0.2 mV/decade for tartrazine ion over a wide concentration range from 4.3 × 10−7 to 1.0 × 10−2 and 1.1 × 10−7 to 1.0 × 10−2 M. The lower detection limits: 3.2 × 10−7 and 5.5 × 10−8 M. Short response time (5–8 s) over the pH range 3.8–7.7 and 4.2–8.1. The proposed sensors display significantly high selectivity for TZ ion over a wide variety of sugars, some anions, common organic, inorganic compounds and additives. The developed electrodes were applied to the potentiometric determination of tartrazine ion in different kinds of foodstuffs: solid jelly (strawberry and custard) powder samples and soft drink (orange) samples with satisfactory results. 相似文献
102.
Salman R. Salman Neeran D. Al-Shama'a 《Polymer-Plastics Technology and Engineering》2013,52(4):343-349
Poly(acrylonitrile/butadiene/styrene) (ABS) is a two-phase material consisting of elastomer particles in a glassy polymer matric of styrene and acrylonitrile (SAN) [1]. The photooxidation of ABS was the subject of several studies [2, 3]. It was suggested that several processes will take place during photooxidation. These changes include the formation of hydroperoxide [4], chain breakage of the polystyrene, and the oxidation of the polymer as it was monitored by IR spectroscopy [4–6]. Also photooxidation affect the polybutadiene in ABS and oxidizes it, which results in the formation of hydroperoxide. There are no data available on the thermal degradation of ABS. In a previous study the thermal aging of recycled high-impact polystyrene was studied using UV-vis spectroscopy [7]. It was found that this method provided very useful information about the degradation of several industrial polymers [8–12]. In this paper thermal degradation of ABS is investigated by UV-vis and IR spectroscopy. 相似文献
103.
N.J. Salman Ahmed Irfan Anjum Badruddin Z.A. Zainal H.M.T. Khaleed Jeevan Kanesan 《International Journal of Heat and Mass Transfer》2009,52(13-14):3070-3078
In this paper, numerical study of heat transfer in a conical annular cylinder fixed with saturated porous medium is presented. The heat transfer is assumed to take place by natural convection and radiation. The inner surface of conical cylinder is maintained at uniform wall temperature. The governing partial differential equations are non-dimensionalised using suitable non-dimensional parameters and then solved by using finite element method. The porous medium is divided using triangular elements with uneven element size. A computer software is used to solve the coupled momentum and energy equations in an iterative manner. The results are discussed for various values of geometric and physical parameters of porous medium with emphasis on cone angle of the cylinder. It is seen that the cone angle plays a vital role in heat transfer from the hot surface to porous medium. 相似文献
104.
Sehrosh Mir Mushtaq Ahmad Mir Ajab Khan Muhammad Zafar Sarwat Jahan Shazia Sultana Munazza Jabeen Salman Majeed 《Microscopy research and technique》2019,82(9):1401-1409
The research was performed to investigate pollen morphology of endangered species of Capparidaceae in subtropical regions of Pakistan. The distinguishing characters were investigated by using light microscope and scanning electron microscope. Palynological study is comprised of pollen shape, pollen type, exine sculpturing, polar and equatorial diameter, length and width of colpi, mesocolpium, and exine thickness. In polar view, Cleome viscosa exhibited the highest pollen size 26.4 (32.7–24.5 μm) ±0.776 whereas Capparis spinosa appeared to be the lowest 12.6 (14.5?10.7 μm) ±0.400. In equatorial view, Cleome viscosa had the largest pollen size 17.1 (20.0–15.0 μm) ±0.606 and Capparis spinosa had the smallest pollen size 9.7 (12.50–8.00 μm) ±0.394. The maximum fertility percentage has been observed in Capparis spinosa, that is, 98.96% and minimum in Cleome viscosa, that is, 82.93%. Diagnostic key has been constructed to state the essential diagnostic features by means of which the taxa can be identified. Remarkable variations have been observed in pollen size, shape, and exine sculpturing. All the selected species were tricolporate. Prolate to subprolate pollen were observed. There is a great variation existed in exine sculpturing such as in Capparis decidua and C. sp. nova sculpturing is reticulate, in Capparis himalayensis sculpturing is Scabrate granulate, in Capparis spinosa sculpturing is Psilate, in Cleome viscosa sculpturing is regulate‐reticulate, in Dipterygium glaucum sculpturing is regulate and in Gynandropsis gynandra sculpturing is striate‐regulate. On the basis of overall characteristics of pollen it seems that palynology of this family is helpful at the generic and specific level. 相似文献
105.
Muhammad Amir Khan Adnan Ahmad Salman Noshear Arshad Ahsan Nazir Sheraz Ahmad Muhammad Qamar Khan Amir Shahzad Aamir Naseem Satti Muhammad Bilal Qadir Zubair Khaliq 《应用聚合物科学杂志》2021,138(24):50562
One dimensional (1D) nanostructures and its derivatives can be manipulated to serve special functions like hollow structure, and higher surface area. 1D TiO2 nanotube-in-nanofibers (NF@NT) are developed through triaxial electrospinning followed by a calcination process. A blended solution of polyvinyl pyrrolidone and tetra-butyl titanate is used in outer and inner layers of nanofibers, respectively, while paraffin oil is used in the middle layer. The optimized triaxial nanofibers of 669.4 ± 52.43 nm are developed at 7.5 w/w% concentration, 28 kV applied voltage, and 24 cm spinning distance. TiO2 NF@NT structure is obtained through calcination of optimized triaxial nanofibers at 550°C. Subsequently, the morphology of TiO2 NF@NT and its uniform diameter distribution is confirmed through scanning electron microscopy. Fourier-transform infrared spectroscopy results indicates the formation of TiO2 NF@NT. X-Rays diffraction pattern peaks also reveals the presence of both anatase and rutile crystalline phases. The presence of only titanium (Ti) and oxygen (O) elements in the TiO2 NF@NT is confirmed through energy dispersive X-ray spectroscopy. Brunauer–Emmett–Teller analysis indicates that TiO2 NF@NT has a higher specific surface area of ~141.68 m2/g compared with the solid TiO2 nanofiber (~75.31 m2/g). This study can be adopted to develop TiO2 NF@NT for wide range of application. 相似文献
106.
In the present work, the conventional natural gas dehydration method (CDM) and stripping gas method (SGM) are technically and economically analyzed, utilizing Aspen HYSYS and Aspen Process Economic Analyzer (APEA), respectively. To optimize the CDM and SGM, the sensitivities of the water content of dry gas, reboiler duty and raw material loss are analyzed against solvent rate and stripping gas rate. The optimized processes are set to achieve a targeted value of water content in dry gas and analyzed at optimized point. The analysis shows that SGM gives 46% lower TEG feed rate, 42% lower reboiler duty and 99.97% pure regenerated TEG. Moreover, economic analysis reveals that SGM has 38% lower annual operating cost compared to CDM. According to results, from both technical and economic point of view, SGM is more feasible for natural gas dehydration compared to CDM. 相似文献
107.
Firat Salman Hilal C. Kazici Hilal Kivrak 《Frontiers of Chemical Science and Engineering》2020,14(4):629
Novel PdCoAg/C nanostructures were successfully synthesized by the polyol method in order to develop electrocatalysts, related to the glucose sensor performance of the high glycemic index in beverages. The characterization of this novel PdCoAg/C electrocatalyst was performed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and high-resolution transmission electron microscopy equipped with energy dispersive X-ray. The characterization results revealed that electronic state of the PdCoAg/C electrocatalyst was modified by the addition of the third metal. The electrochemical performances of the sensor were investigated by cyclic voltammetry and differential pulse voltammetry. The prepared enzyme-free sensor exhibited excellent catalytic activity against glucose with a wide detection range (0.005 to 0.35 mmol∙L−1), low limit of detection (0.003 mmol∙L−1), high sensitivity (4156.34 µA∙mmol−1∙L∙cm−2), and long-term stability (10 days) because of the synergistic effect between the ternary metals. The glucose contents of several energy drinks, fruit juices, and carbonated beverages were analyzed using the novel PdCoAg/NGCE/C sensor system. These results indicate the feasibility for applications in the foods industry. 相似文献
108.
Salman Ayesha Qureshi Ijaz Mansoor Saleem Shahryar Saeed Sarah Alyaei Bahman R. 《Wireless Networks》2018,24(6):2205-2219
Wireless Networks - Cognitive radios and femtocell networks are gaining much popularity due to the formers ability to carry out unlicensed transmission in licensed bands and the latter’s... 相似文献
109.
110.
Nazir Salman Price Brad Surendra Nanda C. Kopp Katherine 《Information Technology and Management》2022,23(3):193-211
Information Technology and Management - Agile development is known for efficient software development practices that enable teams to quickly develop software to cope with changing requirements.... 相似文献