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971.
Radhi M. Chyad Mohd Zubir Mat Jafri Kussay N. Mutter Kamarulazizi Ibrahim 《Optik》2012,123(10):860-862
By using 3-D geometric optics, the effect of a modified cladding on the transmission of light through optical fiber is investigated. Analysis of the light transmission of the optical fiber as function of the modified cladding refraction index and length are presented for various input illumination focused and compared with 3-D ray theory. Applications to chemical sensors are also discussed.The intensity of light signal transmitted through an optical fiber, which its cladding over a finite length is removed, is used as a sensor of refractive of liquids, in which the fiber is immersed. The transmitted light intensity is measured as a function of liquid refractive index for different lengths of the unclad section of the fiber and at each unclad length its sensitivity to change in refractive index of liquid is presented. 相似文献
972.
Aaliya Shah Mohammad Aatif Medha Priyadarshini Mohd Shahnawaz Khan Fakhra Amin Bilqees Bano 《Journal of fluorescence》2012,22(6):1627-1632
Goat liver cystatin was subjected to various chemical modifications in order to ascertain the amino acid residues responsible for its structural and functional integrity. Modification of tryptophan by HNBB led to the complete inactivation of the protein. The inactivation was also accompanied by the complete loss of tryptophan fluorescence at 340 nm. The reaction of liver cystatin with HNBB yielded a characteristic decrease in absorbance at 280 nm. Acetylation of the amino groups of liver cystatin was carried out in the presence of acetic anhydride. The acetylated cystatin showed a decrease in fluorescence intensity at 335 nm which could be attributed to the modification of tyrosine residue due to side reaction. 相似文献
973.
Aida Esmaeilian-Marnani Ahmad Fauzi Abas Mohd Adzir Mahdi Khairulmizam Samsudin 《Optical Review》2012,19(2):71-77
Propagation of temporal 50 femtosecond pulse and pulse stream, which is realized by substituting each input pulse with reduced-order
overlapping soliton pair, is investigated through short standard single-mode fiber. For the pulse stream the initial inter-pulse
delay is selected to be 227 fs and the pulses are to be perturbed to avoid collision with the neighboring pulses. This method
reduces the pulse time delay and properly retains the amplitude despite tradeoff between these two. This is a significant
improvement in the low power femtosecond pulse and pulse stream propagation. 相似文献
974.
Mohd. Abdul Malek Abdullah Renreng Chon Sing Chong 《Radiation Physics and Chemistry》2001,60(6):S98-607
A mechanistic model for the kinetics of polymeric bond scission by X-rays has been developed, with certain assumptions and approximations. The equation governing the number of bonds broken by radiation is found to be Y=1−ae−cD−be−dD where a–d are constants and D the dose. The model has been tested for the case of CR-39 plastic irradiated with X-rays for doses from 50 to 600 kGy. The concentration of CO2 molecules produced inside the plastic, which gave a direct measure of the number of bonds broken by irradiation, was measured using the FTIR absorption bands at 670 and 2350 cm−1. The fraction of the broken bonds was plotted against the radiation dose and the experimental data were found to fit well with the mechanistic model. The values of the various breaking constants for the CR-39 plastic under the mechanistic model were also determined. 相似文献
975.
976.
Hui Ming Ong Ahmad Farhan Ahmad Azmi Sze Wei Leong Faridah Abas Enoch Kumar Perimal Ahmad Akira Omar Farouk Daud Ahmad Israf Mohd Roslan Sulaiman 《Molecules (Basel, Switzerland)》2021,26(24)
The present study focuses on the possible involvement of l-arginine-nitric oxide-cGMP-ATP-sensitive K+ channel pathway in the antinociceptive activity of a novel diarylpentanoid analogue, 2-benzoyl-6-(3-bromo-4-hydroxybenzylidene)cyclohexen-1-ol (BBHC) via a chemical nociceptive model in mice. The antinociceptive action of BBHC (1 mg/kg, i.p.) was attenuated by the intraperitoneal pre-treatment of l-arginine (a nitric oxide synthase precursor) and glibenclamide (an ATP-sensitive K+ channel blocker) in acetic acid-induced abdominal constriction tests. Interestingly, BBHC’s antinociception was significantly enhanced by the i.p. pre-treatment of 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), a selective inhibitor of soluble guanylyl cyclase (p < 0.05). Altogether, these findings suggest that the systemic administration of BBHC is able to establish a significant antinociceptive effect in a mice model of chemically induced pain. BBHC’s antinociception is shown to be mediated by the involvement of l-arginine-nitric oxide-cGMP-ATP-sensitive K+ channel pathway, without any potential sedative or muscle relaxant concerns. 相似文献
977.
Isshadiba Faikah Mustafa Mohd Zobir Hussein Abu Seman Idris Nur Hailini Zainol Hilmi Sharida Fakurazi 《Molecules (Basel, Switzerland)》2021,26(19)
Reports on fungicide-based agronanochemicals in combating disastrous basal stem rot disease in the oil palm industry are scant. Herein, we describe the potential of fungicide nanodelivery agents based on hexaconazole-micelle systems produced using three different surfactants; sodium dodecylbenze sulfonate (SDBS), sodium dodecyl sulfate (SDS) and Tween 80 (T80). The resulting nanodelivery systems were characterized and the results supported the encapsulation of the fungicide into the micelles of the surfactants. We have investigated in detail the size-dependent effects of the as-synthesized micelles towards the inhibition growth of Ganoderma Boninense fungi. All the nanodelivery systems indicate that their size decreased as the surfactant concentration was increased, and it directly affects the fungal inhibition. It was also found that Tween 80, a non-ionic surfactant gave the lowest effective concentration, the EC50 value of 2, on the pathogenic fungus Ganoderma boninense compared to the other anionic surfactants; SDBS and SDS. This study opens up a new generation of agronanofungicide of better efficacy for Ganoderma disease treatment. 相似文献
978.
Harumi Kaga Atsushi Narumi Toshifumi Satoh Takeshi Matsuda Mohd. Sharfuddin Toyoji Kakuchi 《Macromolecular Symposia》2002,181(1):95-100
Coupling reactions of TEMPO-terminated polystyrene (PS-TEMPO) with divinylbenzene were performed in the presence of vinyl saccharides 1 , successfully producing star-shaped polystyrenes with glycoconjugated core 2 . Amphiphilic star-shaped polystyrenes with cores containing saccharide as hydrophilic segments 3 were obtained by the deacetylation of 2 , which exhibited an encapsulation ability toward methyl orange (MO) in chloroform. A positive Cotton effect was observed in the CD spectrum for the MO/ 3 in the adsorption area of MO, indicating that MO existed in a chiral segment, i.e., the glycoconjugated core. 相似文献
979.
Kaushik Kumar Bharadwaj Bijuli Rabha Siddhartha Pati Tanmay Sarkar Bhabesh Kumar Choudhury Arpita Barman Dorothy Bhattacharjya Ankit Srivastava Debabrat Baishya Hisham Atan Edinur Zulhisyam Abdul Kari Noor Haslina Mohd Noor 《Molecules (Basel, Switzerland)》2021,26(21)
Gold nanoparticles (AuNPs) have been widely explored and are well-known for their medical applications. Chemical and physical synthesis methods are a way to make AuNPs. In any case, the hunt for other more ecologically friendly and cost-effective large-scale technologies, such as environmentally friendly biological processes known as green synthesis, has been gaining interest by worldwide researchers. The international focus on green nanotechnology research has resulted in various nanomaterials being used in environmentally and physiologically acceptable applications. Several advantages over conventional physical and chemical synthesis (simple, one-step approach to synthesize, cost-effectiveness, energy efficiency, and biocompatibility) have drawn scientists’ attention to exploring the green synthesis of AuNPs by exploiting plants’ secondary metabolites. Biogenic approaches, mainly the plant-based synthesis of metal nanoparticles, have been chosen as the ideal strategy due to their environmental and in vivo safety, as well as their ease of synthesis. In this review, we reviewed the use of green synthesized AuNPs in the treatment of cancer by utilizing phytochemicals found in plant extracts. This article reviews plant-based methods for producing AuNPs, characterization methods of synthesized AuNPs, and discusses their physiochemical properties. This study also discusses recent breakthroughs and achievements in using green synthesized AuNPs in cancer treatment and different mechanisms of action, such as reactive oxygen species (ROS), mediated mitochondrial dysfunction and caspase activation, leading to apoptosis, etc., for their anticancer and cytotoxic effects. Understanding the mechanisms underlying AuNPs therapeutic efficacy will aid in developing personalized medicines and treatments for cancer as a potential cancer therapeutic strategy. 相似文献
980.
Kinetics of the condensation reaction of ninhydrin and the [Ni(II)–histidine]+ complex has been studied spectrophotometrically at pH 5.0, both in aqueous and aqueous–cationic micelles of cetyltrimethylammonium bromide (CTAB). The same product was obtained in both the media. The results obtained in the micellar medium are treated quantitatively in terms of the kinetic pseudo‐phase and Piszkiewicz models. The rate constants, binding constants with the micelles, and the index of cooperativity have been evaluated. On the basis of observed data a possible mechanism has been proposed. The same product was obtained in nonionic micelles of TX‐100, but the studies were hampered due to the appearance of turbidity, whereas anionic micelles of sodium dodecyl sulphate did not catalyze the reaction. © 1999 John Wiley & Sons, Inc. Int J Chem Kinet 31: 47–54, 1999 相似文献