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81.
Abdullah Siti Awanis Jamil Shajarahtunnur Zainuddin Zairunnisa 《Chemistry of Natural Compounds》2022,58(3):548-549
Chemistry of Natural Compounds - 相似文献
82.
Copper oxidation studies were carried out by means of field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS) and electron energy loss spectroscopy (EELS) techniques. The growth of copper oxide occurs as a copper surface comes in an oxygen containing environment. The reaction sequence leading to oxidation of the copper surface is generally accepted to be oxygen chemisorption, nucleation and growth of the surface oxide and bulk oxide growth. HRTEM examination of the cross section of the oxidized copper sample revealed the interface region in between the copper and copper oxide. At high oxidation temperature, formation of micro-voids and separations were observed along this interface region. Poor adhesion at this interface region due to micro-voids and separation were found to be the root cause of delamination issue. EELS analysis determined that for regions with intact interface the oxidation system is Cu/CuO/Cu2O/CuO, however, in regions containing micro-voids or separation it is found to be Cu/Cu2O/CuO. 相似文献
83.
Mohamad Siti Nur Hidayah Muhamad Ida Idayu Khairuddin Nozieana Jusoh Yanti Maslina Mohd 《Journal of Thermal Analysis and Calorimetry》2017,130(3):1473-1480
Journal of Thermal Analysis and Calorimetry - The α-tocopherol (α-toc) degrades faster than both γ- and δ-toc; its degradation rate is 10 times faster than δ-toc. The... 相似文献
84.
Weinstein RD Richards J Thai SD Omiatek DM Bessel CA Faulkner CJ Othman S Jennings GK 《Langmuir : the ACS journal of surfaces and colloids》2007,23(5):2887-2891
We report the formation of self-assembled monolayers (SAMs) onto gold substrates by exposure to lithium dialkyldithiocarbamate salts [(Li+(R2DTC-), where R = n-propyl, n-butyl, n-octyl, n-decyl, n-dodecyl, or n-octadecyl] in ethanol or methylene chloride. The crystallinity and composition of the monolayers were assessed by polarized modulation infrared reflection absorption spectroscopy (PM-IRRAS), wettability was characterized by contact angles of water and hexadecane, thickness was measured by spectroscopic ellipsometry, and barrier properties determined by electrochemical impedance spectroscopy. While the shorter R2DTC-s formed monolayers with liquid-like packing, monolayers prepared from the longest R2DTC- (where R = n-octadecyl) exhibit similar thickness, crystallinity, wettability, and capacitance as monolayers prepared from n-octadecanethiol. The hydrocarbon chains within the monolayers prepared from (C18)2DTC- are less canted on average than those prepared from n-octadecanethiol. Nonetheless, the (C18)2DTC- SAM exhibits an order of magnitude lower resistance against the penetration of redox probes, which is attributed to a higher density of pinhole defect sites. 相似文献
85.
Siti Nur Hazwani Oslan Joo Shun Tan Siti Nurbaya Oslan Patricia Matanjun Ruzaidi Azli Mohd Mokhtar Rossita Shapawi Nurul Huda 《Molecules (Basel, Switzerland)》2021,26(21)
Haematococcus pluvialis, a green microalga, appears to be a rich source of valuable bioactive compounds, such as astaxanthin, carotenoids, proteins, lutein, and fatty acids (FAs). Astaxanthin has a variety of health benefits and is used in the nutraceutical and pharmaceutical industries. Astaxanthin, for example, preserves the redox state and functional integrity of mitochondria and shows advantages despite a low dietary intake. Because of its antioxidant capacity, astaxanthin has recently piqued the interest of researchers due to its potential pharmacological effects, which include anti-diabetic, anti-inflammatory, and antioxidant activities, as well as neuro-, cardiovascular-, ocular, and skin-protective properties. Astaxanthin is a popular nutritional ingredient and a significant component in animal and aquaculture feed. Extensive studies over the last two decades have established the mechanism by which persistent oxidative stress leads to chronic inflammation, which then mediates the majority of serious diseases. This mini-review provides an overview of contemporary research that makes use of the astaxanthin pigment. This mini-review provides insight into the potential of H. pluvialis as a potent antioxidant in the industry, as well as the broad range of applications for astaxanthin molecules as a potent antioxidant in the industrial sector. 相似文献
86.
Deposition of amorphous particles, as a prevalent problem particularly in the spray drying of fruit and vegetable juices, is due to low-molecular weight sugars and is strongly dependent on the condition of the particles upon collision with the dryer wall. This paper investigates the condition of the amorphous particles impacting the wall at different drying conditions with the aim of elucidating the deposition mechanism and physical phenomena in the drying chamber. A model sucrose-maltodextrin solution was used to represent the low-molecular-weight sugar. Particle deposits were collected on sampling plates placed inside the dryer for analyses of moisture content, particle rigidity (using SEM) and size distribution. Moisture content was adopted as a general indicator of stickiness. Product particles collected at the bottom of the experimental dryer were found to have higher moisture than particle deposits on samplers inside the dryer. Moisture content profile in the dryer shows that apart from the atomizer region, where particles are relatively wet, particle deposits at other regions exhibit similar lower moisture content. At the highest temperature adopted in the experiments, particles became rubbery suggesting liquid-bridge formation as the dominant deposition mechanism. Further analysis on particles size distribution reveals a particle segregation mechanism whereby smaller particles follow preferentially to the central air stream while larger particles tend to re-circulate in the chamber, as predicted in past CFD simulation. The findings from this work will form the basis and provide validating data for further modeling of wall deposition of amorphous particles in spray drying using CFD. 相似文献
87.
Haniza Hassan Siti Khadijah Adam Ekram Alias Meor Mohd Redzuan Meor Mohd Affandi Ahmad Fuad Shamsuddin Rusliza Basir 《Molecules (Basel, Switzerland)》2021,26(18)
Treatment of herpes simplex infection requires high and frequent doses of oral acyclovir to attain its maximum therapeutic effect. The current therapeutic regimen of acyclovir is known to cause unwarranted dose-related adverse effects, including acute kidney injury. For this reason, a suitable delivery system for acyclovir was developed to improve the pharmacokinetic limitations and ultimately administer the drug at a lower dose and/or less frequently. In this study, solid lipid nanoparticles were designed to improve the oral bioavailability of acyclovir. The central composite design was applied to investigate the influence of the materials on the physicochemical properties of the solid lipid nanoparticles, and the optimized formulation was further characterized. Solid lipid nanoparticles formulated from Compritol 888 ATO resulted in a particle size of 108.67 ± 1.03 nm with an entrapment efficiency of 91.05 ± 0.75%. The analyses showed that the optimum combination of surfactant and solid lipid produced solid lipid nanoparticles of good quality with controlled release property and was stable at refrigerated and room temperature for at least 3 months. A five-fold increase in oral bioavailability of acyclovir-loaded solid lipid nanoparticles was observed in rats compared to commercial acyclovir suspension. This study has presented promising results that solid lipid nanoparticles could potentially be used as an oral drug delivery vehicle for acyclovir due to their excellent properties. 相似文献
88.
Bruce D. James Siti Mutrofin Brian W. Skelton Allan H. White 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(11):o622-o624
Structural characterization of the title compound, C10H15N2+·PF6−, shows it to be ionic, with the pyridine rather than the piperidine N atom being protonated and forming hydrogen bonds to the counter‐ions, resulting in two independent ion pairs. A number of unusual features are noted, in particular the remarkably close inter‐ring hydrogen contacts [1.97 (3)–2.00 (3) Å] and the considerable differences in the pair of cations, in respect of the torsion angles within the piperidine ring involving the bonds to either side of the N atom. 相似文献
89.
Maryam Haroon Al-Soufi Hussah Abdullah Alshwyeh Haifa Alqahtani Safa Khalil Al-Zuwaid Fatimah Othman Al-Ahmed Fatima Taher Al-Abdulaziz Daniya Raed Khaoula Hellal Nurul Hidayah Mohd Nani Siti Norliyana Zubaidi Nurul Syahidah Mio Asni Hamizah Shahirah Hamezah Nurkhalida Kamal Hessah Al-Muzafar Ahmed Mediani 《Molecules (Basel, Switzerland)》2022,27(15)
Fruits maintain the image as the richest sources of vitamins. Focusing on apricots, utilization of apricot species for many applications is possible due to its various benefits. Many research studies demonstrated different perspectives of apricot, especially in medical used as it can act as antioxidant, anti-inflammatory, and antimicrobial agents. Moreover, in the industrial sectors, apricots can be used in the production of biofuels and batteries. All components of the apricot fruit, including seeds and kernels have been found to possess significant interest. This review is to breach the knowledge gap regarding the key nutrients and chemicals of apricot fruit, contributing to its health-promoting properties to emphasize the noble importance of this fruit in the diet and in the management of several diseases. We also cover the application of apricots in the industry that could be developed as a promising and sustainable source. 相似文献
90.
Three new triruthenium clusters, Ru3(CO)9(μ‐arphos)AsPh3 ( 1 ), Ru3(CO)9(μ‐arphos)As(m‐C6H4Me)3 ( 2 ), and Ru3(CO)9(μ‐arphos)As(p‐C6H4Me)3 ( 3 ) were synthesized via thermal reactions of Ru3(CO)10(μ‐arphos) with different tertiary arsine ligands [AsPh3, As(m‐C6H4Me)3, As(p‐C6H4Me)3]. All these complexes were fully characterized by elemental analysis, FT‐IR, NMR spectroscopy, and single‐crystal X‐ray diffraction. 相似文献