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291.
Shirin Bahrami Amarjeet Bassi Ernest Yanful 《Journal of Sol-Gel Science and Technology》2007,42(2):119-126
The application of silica sol–gel particles containing crude metallothionein (MT) was investigated for cadmium removal from
water. The metallothionein was first extracted from the yeast Scchizosaccharomyces pombe, and entrapped in the sol–gel matrices. Then sol–gel particles with the different sizes (ranging from 45 to 225 μm) were
made. The effect of different flow rates as well as different particle sizes on adsorption of cadmium was investigated. The
particle size has a greater effect on Cd adsorption than flow rate in the system studied. The breakthrough curves in the column
were modeled using an empirical two parameter fixed-bed adsorption model. The model relates the changes of cadmium concentration
in effluent to the standard deviation (σ) and characteristic of time (t
0). 相似文献
292.
Farid Bahrami Henrik Shahgholian 《Proceedings of the American Mathematical Society》1998,126(3):745-750
For set , and let be a measure with compact support. Suppose, for , there are functions and (bounded) domains , both containing the support of with the property that in (weakly) and in the complement of . If in addition is convex, then and .
293.
Moncer A. Hariga Abdulrahman Al-Ahmari Abdel-Rahman A. Mohamed 《European Journal of Operational Research》2007
In this paper, we propose an optimisation model to determine the product assortment, inventory replenishment, display area and shelf space allocation decisions that jointly maximize the retailer’s profit under shelf space and backroom storage constraints. The variety of products to be displayed in the retail store, their display locations within the store, their ordering quantities, and the allocated shelf space in each display area are considered as decision variables to be determined by the proposed integrated model. In the model formulation, we include the inventory investment costs, which are proportional to the average inventory, and storage and display costs as components of the inventory costs and make a clear distinction between showroom and backroom inventories. We also consider the effect of the display area location on the item demand. The developed model is a mixed integer non-linear program that we solved using LINGO software. Numerical examples are used to illustrate the developed model. 相似文献
294.
In this paper, we have investigated the effect of annealing on structural and magnetic properties of La0.8Pb0.2MnO3 (LPMO) polycrystalline samples. Mechanochemical procedure has been used to produce LPMO nanocrystalline samples from oxide precursors. From the AC susceptibility measurements we found that the magnitude of susceptibility increases and the paramagnetic–ferromagnetic (PM–FM) transition width decreases by annealing the ball milled powders. Also, reentrant spin glass (RSG) behavior has been found in high temperature annealed samples. It seems that, due to the evaporation of PbO in high temperature annealed samples, vacancies created in perovskite structure and portion of the Mn3+–O–Mn4+ network is broken. So the FM double-exchange interaction is weakened due to the magnetic dilution and the antiferromagnetc (AFM) phase fraction increases in high temperature annealed samples. The competition between FM double-exchange interaction and AFM super-exchange interaction produces spin frustration and is responsible for the occurrence of RSG. 相似文献
295.
Pratibha Pandey Fahad Khan Faisal Abdulrahman Alzahrani Huda A. Qari Mohammad Oves 《Molecules (Basel, Switzerland)》2021,26(18)
Rutin has been well recognized for possessing numerous pharmacological and biological activities in several human cancer cells. This research has addressed the inhibitory potential of rutin against the Jab1 oncogene in SiHa cancer cells, which is known to inactivate various tumor suppressor proteins including p53 and p27. Further, the inhibitory efficacy of rutin via Jab1 expression modulation in cervical cancer has not been yet elucidated. Hence, we hypothesized that rutin could exhibit strong inhibitory efficacy against Jab1 and, thereby, induce significant growth arrest in SiHa cancer cells in a dose-dependent manner. In our study, the cytotoxic efficacy of rutin on the proliferation of a cervical cancer cell line (SiHa) was exhibited using MTT and LDH assays. The correlation between rutin and Jab1 mRNA expression was assessed by RT-PCR analysis and the associated events (a mechanism) with this downregulation were then explored via performing ROS assay, DAPI analysis, and expression analysis of apoptosis-associated signaling molecules such as Bax, Bcl-2, and Caspase-3 and -9 using qRT-PCR analysis. Results exhibit that rutin produces anticancer effects via inducing modulation in the expression of oncogenes as well as tumor suppressor genes. Further apoptosis induction, caspase activation, and ROS generation in rutin-treated SiHa cancer cells explain the cascade of events associated with Jab1 downregulation in SiHa cancer cells. Additionally, apoptosis induction was further confirmed by the FITC-Annexin V/PI double staining method. Altogether, our research supports the feasibility of developing rutin as one of the potent drug candidates in cervical cancer management via targeting one such crucial oncogene associated with cervical cancer progression. 相似文献
296.
Mahsa Pourmirz Shahla Ebrahimnezh Ali Ramazani Aidin Bahrami Sholeh. Alaei Ali. Reza Dadrass 《无机化学学报》2019,35(2):344-350
通过2-溴-1-(对甲苯基)乙醛与三(对甲苯基)膦的反应制备α-磷配体:1-(对甲苯基)-2-(三对甲苯基-5-亚磷酰基)乙醛(L)。氯化镉和溴化汞与L分别反应,生成配合物[Cd(L)Cl2]2(C1)和[Hg(L)(μ2-Br)Br]2(C2)。用IR和NMR(1H,13C,31P)对配合物进行了表征。通过单晶X射线衍射测定了C2的结构,并在B3LYP/6-31G*水平对C2的结构进行了DFT计算研究,以揭示C2的复合反应位点与Schiff碱等亲核基团的相互作用。 相似文献
297.
Mohammed Mansour Quradha Rasool Khan Mujeeb-ur- Rehman Abdulrahman Abohajeb 《Natural product research》2019,33(17):2554-2559
Chemical composition, antioxidant, anticancer, and antimacrobial activities of essential oil obtained from leaves of Rumex nervosus has been evaluated here for the first time. GC/MS analysis reveals the presence of Palmitoleic Acid (28.35%) and Palmitic acid, (25. 37%) as their methyl ester as major components. The essential oil showed significant DPPH radical scavenging activity (94.907 ± 0.1089% and 94.003 ± 0.0749%) at concentration (100 and 80) μg/mL respectively. The oil showed promising activity against staph aureus, while showed weak activity against (Hela and 3T3) cell lines. The crude extract / fractions of R. nervosus (leaves) showed significant antioxidant activity at dose (100 and 80) μg/mL. Futhermore the crude showed significant activity against (MCF-7 and MDA-MB-231) cell lines with IC50 (20.5138 ± 0.933 and 25.1728 ± 0.9176) μg/mL respectively, and chloroform fraction showed good activity against (MCF-7 and MDA-MB-231) cell lines with IC50 (31.154 ± 0.965 and 42.269 ± 2.1045) μg/mL. 相似文献
298.
Naeem Jan Abdul Nasir Mohsin S. Alhilal Sami Ullah Khan Dragan Pamucar Abdulrahman Alothaim 《Entropy (Basel, Switzerland)》2021,23(9)
Recently, there has been enormous development due to advancements in technology. Industries and enterprises are moving towards a digital system, and the oil and gas industries are no exception. There are several threats and risks in digital systems, which are controlled through cyber-security. For the first time in the theory of fuzzy sets, this research analyzes the relationships between cyber-security and cyber-crimes in the oil and gas sectors. The novel concepts of complex intuitionistic fuzzy relations (CIFRs) are introduced. Moreover, the types of CIFRs are defined and their properties are discussed. In addition, an application is presented that uses the Hasse diagram to make a decision regarding the most suitable cyber-security techniques to implement in an industry. Furthermore, the omnipotence of the proposed methods is explained by a comparative study. 相似文献
299.
Abdulrahman Th. Mohammad Sohif Bin Mat M. Y. Sulaiman K. Sopian Abduljalil A. Al-abidi 《Heat and Mass Transfer》2013,49(11):1587-1593
A computer simulation using MATLAB is investigated to predict the distribution of air stream parameters (humidity ratio and temperature) as well as desiccant parameters (temperature and concentration) inside the parallel plate absorber. The present absorber consists of fourteen parallel plates with a surface area per unit volume ratio of 80 m2/m3. Calcium chloride as a liquid desiccant flows through the top of the plates to the bottom while the air flows through the gap between the plates making it a cross flow configuration. The model results show the effect of desiccant mass flow rate on the performance of the dehumidifier (moisture removal and dehumidifier effectiveness). Performance comparisons between present cross-flow dehumidifier and another experimental cross-flow dehumidifier in the literature are carried out. The simulation is expected to help in optimizing of a cross flow dehumidifier. 相似文献
300.
Abdulrahman I. Al-Mansour Salih S. Al-Juaid Colin Eaborn Peter B. Hitchcock 《Journal of organometallic chemistry》1994,480(1-2):139-143
The unit cell in a crystal of (Me3Si)3CSiPh2OH contains two dimers, one of them centrosymmetric. There are no significant differences between the geometries of the molecules in the two types of dimers, in which the components appear to be held together by hydrogen bonding of the type Si---(H)O.…H--- O---Si. kw]Silicon; Crystal structure; Hydrogen bonding; silanol 相似文献