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131.
M. R. Nur Illiyin J. M. N. Marikkar M. Shuhaimi B. Mahiran M. S. Miskandar 《Journal of the American Oil Chemists' Society》2013,90(10):1485-1493
A study was carried out to compare the thermo-physical behaviors of canola–Engkabang fat blends with those of lard (LD). Four blends were prepared by mixing canola oil with Engkabang fat (CaO/EF) in different ratios: EF-1, 75:25; EF-2, 70:30; EF-3, 65:35; EF-4, 60:40. The fat blends and LD were compared in terms of their basic physicochemical parameters, fatty acid and triacylglycerol (TAG) compositions, melting, solidification, hardness, and polymorphic properties. The slip melting points (SMP) of the fat blends were found to range from 24.8 to 31.2 °C; EF-2 was found to display an SMP value closer to that of LD. With respect to the melting curve of CaO, the melting curves of all fat blends were found to display an additional high-melting thermal transition in the temperature region above 10 °C. The peak maximum of the high-melting thermal transition of EF-3 was the closest to that of LD. The solid fat content (SFC) value of EF-3 was equal to that of LD at 25 °C, whereas the SFC values of EF-2 and LD were similar at 30 to 40 °C. According to textural analysis, EF-2 was found to display a hardness value somewhat closer to that of LD. X-ray diffraction analysis showed that LD and fat blends EF-1, EF-2, and EF-3 display β polymorphic forms. 相似文献
132.
Fatma Nur Arslan Huseyin Kara Hamide Filiz Ayyildiz Mustafa Topkafa Ismail Tarhan Adnan Kenar 《Journal of the American Oil Chemists' Society》2013,90(8):1179-1193
The main goal of the present study was (i) to determine the formation of degradation products in cottonseed oil (CSO) blends during deep frying process by adsorption and high performance size exclusion chromatography techniques and (ii) to evaluate the impacts of food additives on total polar (TPC) and polymeric compound (PTAG) formation using a chemometric approach. In order to prepare the frying CSO blends; ascorbic palmitate, mixed tocopherols, dimethylpolysiloxane, lecithin and sesame oils were used as additives. To determine the real impacts of additives, a quarter-fraction factorial experimental design with two levels and five factors was used. The changes in TPC and PTAG data were carefully evaluated during 10 h of frying at 170 ± 5 °C with normal distribution (ND) graphs and analyzed using a one-way analysis of variance (ANOVA), followed by Tukey’s Post-hoc test (α = 0.05). The results indicated that the increasing values for TPC and PTAG during the frying processes for all blends, TPC and PTAG contents reached maximum levels of 16.37 and 6.01 % respectively, which are below the limit values stated by official authorities for the quality assessment of frying oils. The ANOVA test results were in good agreement with ND graphs and data indicated that the impact of mixed tocopherols was significant for TPC formation, meanwhile the impact of lecithin and ascorbic palmitate × dimethylpolysiloxane were significant for PTAG formation. Thus, the present study should be considered to be a very useful guide for developing new frying oil formulations based on CSO by using food additives. 相似文献
133.
Precast AASHTO concrete bridge I-beams are often supported at the ends by elastomeric bearing pads. The bearing pad-bridge beam interface defines support boundary conditions that may affect the performance of the bridge. In this study, finite-element modeling was used to validate AASHTO bearing stiffness specifications. Stiffness characteristics of the Florida DOT bearing pads were theoretically determined under varying elastomer shear modulus values. Finite-element models of AASHTO Types III and V beams were subjected to simulated static truckloads. Vertical and horizontal spring elements simulating new bearing pads were incorporated at the ends of the beam models. A full section of a bridge on U.S. Route 27 was also modeled, and the results were compared with field tests. In general, the restraint effects of the bearing pads are beneficial to the performance of the beams and the bridge. The beneficial effect, however, is small for new bearing pads and more pronounced under a drastic increase in bearing stiffness due to aging and colder temperatures. Such a dramatic increase in bearing stiffness must be justified if the beneficial elements are to be utilized. Current Florida DOT bearing pads are serving the main purpose of their application, which is to provide minimum horizontal restraint force to the beams while allowing horizontal movement. 相似文献
134.
Xiaofan Wang Keisuke Shinokita Hong En Lim Nur Baizura Mohamed Yuhei Miyauchi Nguyen Thanh Cuong Susumu Okada Kazunari Matsuda 《Advanced functional materials》2019,29(6)
Atomically thin‐layered ReS2 with a distorted 1T structure has attracted attention because of its intriguing optical and electronic properties. Here, the direct and indirect exciton dynamics of a three‐layered ReS2 is investigated by polarization‐resolved transient photoluminescence (PL) and ultrafast pump‐probe spectroscopy. The various time scales of the decay signals of the time‐resolved PL (<10 ps), with monitoring of the populations of electron–hole pairs (exciton), and the transient differential reflectance (≈1 and 100 ps), with monitoring of the populations of electrons and/or holes in the excited states, are observed. These results reveal the characteristic exciton dynamics: rapid relaxation of direct excitons (electron–hole pairs) and slow relaxation of the momentum‐mismatched indirect excitons accompanied by a one‐phonon emission process. These findings provide important information regarding the indirect bandgap nature of few‐layered ReS2 and its characteristic exciton dynamics, boosting the understanding of the novel electronic and optical properties of atomically thin‐layered ReS2. 相似文献
135.
M. Nur Hossain Syed Ahmad Heinz-Bernhard Kraatz 《International Journal of Hydrogen Energy》2021,46(2):2007-2017
Herein, we report a facile one-step synthesis route to fabricate the coinage metal nanodendrites (NDs) via a tailored galvanic replacement reaction (GRR). Cu, Ag and Au NDs are directly grown on glassy carbon plate (GCP) from the mixture of their precursor solutions and Zn dust. The formed NDs are uniformly distributed to the substrate and obtained the unique structures with sharp tips and tertiary branches. The electrocatalytic activity of the synthesized NDs towards the hydrogen evolution reaction (HER) is further investigated in 0.5 M H2SO4 using linear sweep voltammetry (LSV) and the Tafel slope. The results demonstrate that the nanodendrites formed through the GRR process exhibit greater catalytical activity towards HER in comparison to the polycrystalline Cu, Ag and Au. The prepared Au NDs exhibits the highest catalytic performance with a current density of ?10.68 mA cm?2 at overpotential of 67 mV and a low Tafel slope of 65 mV dec?1. The simple and easy synthesis approach, the unique morphology and high electrocatalytic activity and excellent stability make the developed Cu, Ag and Au NDs highly efficient catalysts for green energy and electrochemical applications. 相似文献
136.
Gecer Esma Nur 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(11):4402-4409
Journal of Inorganic and Organometallic Polymers and Materials - Salvia species have been used extensively in medicinal and food industries for years due to their significant secondary metabolites... 相似文献
137.
Ongen Atakan Ozcan Hüseyin Kurtulus Elmaslar Ozbas Emine Pangaliyev Yerbol 《Clean Technologies and Environmental Policy》2019,21(6):1281-1291
Clean Technologies and Environmental Policy - Thermochemical decomposition of waste tires was evaluated in order to produce solid and gaseous products within the aim of waste-to-energy concept.... 相似文献
138.
Hazel Marie Kugan Nur Ardiyana Rejab Nurul Amylia Sahruzaini Jennifer Ann Harikrishna Niranjan Baisakh Acga Cheng 《International journal of molecular sciences》2021,22(9)
The natural timing devices of organisms, commonly known as biological clocks, are composed of specific complex folding molecules that interact to regulate the circadian rhythms. Circadian rhythms, the changes or processes that follow a 24-h light–dark cycle, while endogenously programmed, are also influenced by environmental factors, especially in sessile organisms such as plants, which can impact ecosystems and crop productivity. Current knowledge of plant clocks emanates primarily from research on Arabidopsis, which identified the main components of the circadian gene regulation network. Nonetheless, there remain critical knowledge gaps related to the molecular components of circadian rhythms in important crop groups, including the nitrogen-fixing legumes. Additionally, little is known about the synergies and trade-offs between environmental factors and circadian rhythm regulation, especially how these interactions fine-tune the physiological adaptations of the current and future crops in a rapidly changing world. This review highlights what is known so far about the circadian rhythms in legumes, which include major as well as potential future pulse crops that are packed with nutrients, particularly protein. Based on existing literature, this review also identifies the knowledge gaps that should be addressed to build a sustainable food future with the reputed “poor man’s meat”. 相似文献
139.
Ayşegül Yücel Selda Sezer Emre Birhanlı Tuba Ekinci Emine Yalman Tolga Depci 《Ceramics International》2021,47(1):626-633
In the present study, undoped whitlockite and ZnO doped-Whitlockite, which is the second most abundant inorganic material in bone structure, were synthesized from sea urchin skeleton. The obtained bioceramic materials were characterized by XRD, FT-IR, and SEM and their antibacterial activities were determined using the inhibition zone diameters of Escherichia coli and Pseudomonas aeruginosa as gram negative bacteria and Staphylococcus aureus as gram positive bacterium after 24 h incubation. The characterization studies showed that nano size homogenous biocereamic whitlockite (Ca2.86Mg0.14(PO4)2) was synthesized from the sea urchin skeleton. After dopping process, the main structure of the whitlockite keeps stable, showing a dopping concentration-independent character. On the other hand, the peaks belonging to ZnO were started to seen in the XRD pattern with increasing the level of ZnO-concentration (after 7 %). All experimental results point out that the obtained whitlockites are viable nominate candidates for bioceramic materials and the results of antibacterial sensitivity prove the inhibitory effect towards Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus for ZnO-doped-whitlockite. 相似文献
140.
Andi Nur Nilamyani Firda Nurul Auliah Mohammad Ali Moni Watshara Shoombuatong Md Mehedi Hasan Hiroyuki Kurata 《International journal of molecular sciences》2021,22(5)
Nitrotyrosine, which is generated by numerous reactive nitrogen species, is a type of protein post-translational modification. Identification of site-specific nitration modification on tyrosine is a prerequisite to understanding the molecular function of nitrated proteins. Thanks to the progress of machine learning, computational prediction can play a vital role before the biological experimentation. Herein, we developed a computational predictor PredNTS by integrating multiple sequence features including K-mer, composition of k-spaced amino acid pairs (CKSAAP), AAindex, and binary encoding schemes. The important features were selected by the recursive feature elimination approach using a random forest classifier. Finally, we linearly combined the successive random forest (RF) probability scores generated by the different, single encoding-employing RF models. The resultant PredNTS predictor achieved an area under a curve (AUC) of 0.910 using five-fold cross validation. It outperformed the existing predictors on a comprehensive and independent dataset. Furthermore, we investigated several machine learning algorithms to demonstrate the superiority of the employed RF algorithm. The PredNTS is a useful computational resource for the prediction of nitrotyrosine sites. The web-application with the curated datasets of the PredNTS is publicly available. 相似文献