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21.
S. A. Kandil H. A. Hanafi H. Aglan Z. A. Saleh 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):609-614
The adsorption behaviour of La/Ce system on Dowex 50W-X8 in different media, namely, nitric acid, acetate buffer and citrate
buffer was studied as a function of the concentration of nitric acid and buffer pH. In addition, in cation-exchange column
chromatography experiments, three different eluants, namely, citrate buffer of pH 5.5, 0.1 M EDTA and 0.2 M α-HIBA, were employed
for separation of Ce(III) from La(III). The optimum conditions for improvement of radiochemical separation of no-carrier-added
139Ce from proton irradiated lanthanum were applied using the most suitable chelating agent 0.2 M α-HIBA. The purification of
139Ce from macro amount of La(III) was done using two columns in a sequence. The target was prepared by pressing. The production
of high radionuclidic and chemical purity 139Ce via irradiation of lanthanum oxide target at MGC-20 cyclotron of proton energy 14.5 MeV was described. The experimental
yield was found to be 200 kBq/μA h. 相似文献
22.
Wafaa S. Hamama Mona E. Ibrahim Hadeer A. Raoof Hanafi H. Zoorob 《Research on Chemical Intermediates》2017,43(11):6259-6291
This review provides a survey of the advances in the methods of formation and chemical reactivity of bicyclic [1,3,4]thiadiazole 5-5 systems containing ring-junction nitrogen over the period from 1989 to the beginning of 2017. 相似文献
23.
Youssef Masmoudi Habib Chabchoub Saïd Hanafi Ahmed Rebaï 《Journal of Mathematical Modelling and Algorithms》2010,9(3):247-255
In this paper we propose a new procedure for classification based on a hybrid approach. The classification problem is solved
by minimizing the distance between the components of each clusters and the centers of the clusters. The determination of the
cluster centers is therefore a critical step in our approach and was addressed used the k-means algorithm. Once the centers
of each class are determined, the rule of center neighbourhood is applied to assign an element to a class using mathematical
programming. The implementation of our hybrid approach was validated on benchmark datasets and applied to an original biological
dataset on 84 breast cancer tumours. Each tumour was measured for five parameters corresponding to the expression of five
biomarkers (proteins). The obtained classification was discussed using biological knowledge and classical clinical experts’
classification of breast tumors. 相似文献
24.
In this paper, we present the first model of co-opetition for a Hub Location Problem between two logistics service provider (LSPs) companies where the mother company is the owner of infrastructure. The LSPs would like to cooperate with each other by establishing joint edges with limited capacities connecting their service networks. Such services are in form of pendulum services (a direct service between two points) between nodes of different networks. Additional market can be generated as a result of joining the two networks. At the same time, a competition is taking place between the two operators to increase their share from the additional market generated. In order to solve this problem, we propose a matheuristic approach combining a local search algorithm and a Lagrangian relaxation-based approach. In our matheuristic algorithm, the neighbourhood solutions are evaluated using a Lagrangian relaxation-based approach. Numerical results of applying the proposed algorithm on a real case study of the problem are presented. 相似文献
25.
Tanojo H. Bouwstra J. A: Junginger H. E. Boddé H. E. 《Journal of Thermal Analysis and Calorimetry》1999,57(1):313-322
The thermal behaviour of human stratum corneum (SC) with various hydration levels was studied using differential thermal analysis DSC within the temperature range of –130 to 120°C. SC containing 20% water, resembling the intact condition, shows thermal transitions at around –20°C (representing water in skin), –10, 40, 70°C (representing skin lipids), 85°C (representing protein-associated lipids) and 100°C (representing skin protein). Dehydration of SC causes the transitions at –20 and 100°C to be invisible. Lipid extraction followed by dehydration eliminates all transitions. Further hydration produces a transition of water at around 0°C with a huge change in enthalpy. The perturbation effects of penetration enhancers fatty acids (FA) and propylene glycol (PG) were studied using DTA on SC after pretreatment with PG alone and FA/PG. The application of PG alone shifted the transitions at 70 and 85°C to lower temperatures. Additionally, the application to dehydrated stratum corneum removes the transitions at –10°C. Saturated fatty acids, e.g. nonanoic and decanoic acids, exert barely noticeable effects on the thermal behaviour of SC suggesting that they easily mix with the skin lipids. Thermal analysis also revealed that the cis-9- and 13-isomers of octadecenoic acid (monounsaturated fatty acids) form a separate domain containing mostly the pure fatty acids within the SC lipids and suppress the lipid transitions at 70/80°C. Polyunsaturated fatty acids linoleic and -linolenic acids — form separate domains but do not completely suppress the SC lipid transitions at 70/80°C as monounsaturated acids do. This study suggests different ways of perturbation by various fatty acids.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
26.
Several papers have already stressed the interest of latent root regression and its similarities to partial least squares
regression. A new formulation of this method which makes it even simpler than the original method to set up a prediction model
is discussed. Furthermore, it is shown how this method can be extended not only to the case where it is desired to predict
several response variables from a set of predictors but also to the multiblock setting where the aim is to predict one or
several data sets from several other data sets. The interest of the method is illustrated on the basis of a data set pertaining
to epidemiology. 相似文献
27.
Mokashi Imran Khan Sher Afghan Abdullah Nur Azam Bin Azami Muhammad Hanafi Afzal Asif 《Journal of Thermal Analysis and Calorimetry》2020,141(6):2555-2571
Journal of Thermal Analysis and Calorimetry - The use of Li-ion battery in electric vehicles is becoming extensive in the modern-day world owing to their high energy density and longer life. But... 相似文献
28.
Seven samples of chromium suboxides of composition CrO3-x are prepared from the thermal decomposition of CrO3. The O/Cr ratio of each is determined by chemical analysis and ignition loss. X-Ray analysis reveals that they are more or less of the correct structure contaminated with the nearest suboxide. The specific gravity is determined pycnometrically and varies linearly with the O/Cr ratio.TGA indicates weight losses which agree with the calculated O/Cr ratio. DTA and DTG give endothermic peaks corresponding to the temperature of preparation of the successive samples. 相似文献
29.
Ahmed Z. Abdel Azeiz Donia K. Hanafi Sameh E. Hasanein 《Natural product research》2016,30(16):1816-1823
Thirty actinomycete isolates were isolated from soil and tested against Candida albicans in vitro. The active isolate was identified by 16s-rRNA gene sequencing method as Streptomyces toxytricini. The antifungal compound was extracted with ethyl acetate followed by diethyl ether. Both HPLC and GC–MS analysis confirmed presence of one pure compound in the diethyl ether extract. The compound is a yellow liquid has a maximum absorbance at 240 nm in methanol. The chemical structure was elucidated by 1D and 2D-NMR and IR analyses. The elucidated molecular formula was C36H54O14. The compound is a polyacetal tricyclononane derivative, composed of a tricyclononane ring attached from the carbon atom number four with an oligo-acetal chain (six acetal groups in chain) and from the carbon atom number seven with a methoxy carbonyl benzene-1,3-dicarboxylic acid. The purposed name is: 4- {[tricycle(3.2.1.11,3)non-8-yl] methoxy carbonyl benzene-1,3-dicarboxylic acid} (2,4,5,6,7,8,9 heptaoxa, 3-ethoxy, 5,6,7,9-tetramethyl unidecane). 相似文献
30.
Aslina Pahrudin Arrozi Siti Nur Syazwani Shukri Wan Zurinah Wan Ngah Yasmin Anum Mohd Yusof Mohd Hanafi Ahmad Damanhuri Suzana Makpol 《Applied biochemistry and biotechnology》2017,183(3):853-866
Neuroblastoma cell lines such as SH-SY5Y are the most frequently utilized models in neurodegenerative research, and their use has advanced the understanding of the pathology of neurodegeneration over the past few decades. In Alzheimer’s disease (AD), several pathogenic mutations have been described, all of which cause elevated levels of pathological hallmarks such as amyloid-beta (Aβ). Although the genetics of Alzheimer’s disease is well known, familial AD only accounts for a small number of cases in the population, with the rest being sporadic AD, which contains no known mutations. Currently, most of the in vitro models used to study AD pathogenesis only examine the level of Aβ42 as a confirmation of successful model generation and only perform comparisons between wild-type APP and single mutants of the APP gene. Recent findings have shown that the Aβ42/40 ratio in cerebrospinal fluid (CSF) is a better diagnostic indicator for AD patients than is Aβ42 alone and that more extensive Aβ formation, such as accumulation of intraneuronal Aβ, Aβ plaques, soluble oligomeric Aβ (oAβ), and insoluble fibrillar Aβ (fAβ) occurs in TgCRND8 mice expressing a double-mutant form (Swedish and Indiana) of APP, later leading to greater progressive impairment of the brain. In this study, we generated SH-SY5Y cells stably transfected separately with wild-type APP, the Swedish mutation of APP, and the Swedish and Indiana mutations of APP and evaluated the APP expression as well as the Aβ42/40 ratio in those cells. The double-mutant form of APP (Swedish/Indiana) expressed markedly high levels of APP protein and showed a high Aβ2/40 ratio compared to wild-type and single-mutant cells. 相似文献