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Preparation of Water Based Polymeric Binders for Paper Surface Coating

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Journal of Surface Engineered materials and Advanced Technology 2014年第3期4卷 140-154页

作者： Samya El-Sherbiny Fatma A. morsy Ayman m. Atta salwa A. Ahmed Chemistry Department College of Science King Saud University Riyadh KSA Chemistry Department Faculty of Science Helwan University Helwan Egypt

Binder is an important ingredient in pigment coating as it is used to impart adhesion, gloss and flexibility to the dried film as well as binding the pigment particles together. The aim of this work was to synthesize polymeric binders via radical copolymerization of acrylic acid (AA) with maleic anhydride (mA) and with 2-acrylamido-2-methyl-1-propane sulfonic acid (AmPS). The chemical structures of the prepared binders were characterized by FTIR and 1HNmR analysis. The rheology of the prepared binders was also investigated. The prepared binders were applied in paper coating suspensions and their effects on optical, mechanical, and physical properties in addition to printability of the coated paper were studied. The results showed that acrylic maleic anhydride copolymers increased the adhesion, gave good film forming properties and good surface activity which increased print quality of paper coating. It was also found that mA/AA (50:50) and the blend between mA/AA (50:50) with AmPS:AA (30:70) have more suitable coating film properties and have highest pick resistance which is resemble to the commercial binder.

关键词： maleic Anhydride Acrylic Acid Paper Coating Binder Adhesion Print Quality

Energy Efficiency Behavior in Heterogeneous Networks under Various Operating Situations of Cognitive Small Cells

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Wireless Engineering and Technology 2015年第1期6卷 9-23页

作者： Amr A. Fahmy Asmaa m. Saafan Hesham m. El-Badawy salwa El-Ramly Faculty of Engineering Ain-Shams University Cairo Egypt National Telecommunication Institute (NTI) Cairo Egypt

Recently, several approaches were followed for the enhancement and better resource utilization in mobile networks;this is to achieve energy efficient consumption for production and delivery of an information bit. Using Cognitive Femto cells (as a member of the small base stations’ family) proves that, it is an efficient solution for achieving this goal[1]. The use of Energy Efficiency term η has become one of the major indices for measuring the performance of these systems. η is the measure of the overall system Capacity (C)?in bps/Hz versus the Consumed Energy (E) in Joules [2]. In consistence with many researches, analytic models and empirical measurements, η will be investigated throughout the course of this work. Cognitive Base Stations (CBS) (as an element of the system model) which performs the traffic offloading operations is proved to enhance η performance. In this work, a combination of both analytic and simulation models are used to construct a practical system model. The obtained model is then used to illustrate the effect of different operational parameters that are involved in the η problem. On the other hand, the current paper tries to focus on the selection criteria that may be used to design the cooperative cognitive networks in order to achieve the best η indices. Both of CBSs radii as well as the inter-separation distances (between CBSs and mBS location) are examined to obtain best η index for different operation scenarios;in addition, both of capacity and energy consumption are taken into consideration based on practical operating measures. This work proposed several nonlinear equations with fixed parameters to be used by field engineers to achieve the results with minimum reduced computation complexity. So, the current work may be of importance for the regulator bodies as well as the cognitive mobile operators.

关键词： Energy Efficiency Capacity Energy Cognitive Radio Wireless Communications Green Radio

Fabrication and Characterisation of Novel Natural Lycopodium clavatum Sporopollenin microcapsules Loaded In-Situ with Nano-magnetic Humic Acid-metal Complexes

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Journal of Encapsulation and Adsorption Sciences 2016年第4期6卷 109-131页

作者： Amro K. F. Dyab Elham m. Abdallah salwa A. Ahmed mai m. Rabee Chemistry Department Faculty of Science Minia University Minia Egypt

Sporopollenin exines microcapsules, derived from the naturally occurring spores of Lycopodium clavatum, have been loaded in-situ with humic acid sodium salt-Zinc (HA-Zn) complex. The chemical treatment method utilised to prepare the sporopollenin microcapsules from raw spores was discussed and the resulted sporopollenin microcapsules were characterised using SEm, TGA and FTIR. metal complexes of the sodium salt of humic acid and zinc ion were prepared using different protocols and in-situ loaded into the pre-treated sporopollenin microcapsules. The resulted complex was characterised before and after the encapsulation process using FTIR, TGA and XRD techniques. The morphology of the empty and loaded sporopollenin was not altered. Infrared spectroscopy revealed an increase in the absorption for COO– vibrations at 1583 and 1384 cm–1 in the FTIR spectra of HA-Zn complex compared to that of the original sodium salt of humic acid, indicative of bonding of the metal ions in hydrated form to the carboxyl or phenolic hydroxyl groups or both of the sodium humate molecules. TGA results of the HA-Zn complex loaded sporopollenin showed that around %15 of residual HA-Zn was successfully encapsulated indicative of the efficiency of the protocol used. We showed also that biodegradable magnetite nanoparticles can be surface modified with HA and encapsulated into sporopollenin. The resulted biosorbents microcapsules can be used for enhanced magnetic removal of either heavy metals or HA from different aqueous media.

关键词： Biosorbents metal Complexes Sporopollenin Humic Acid magnetite Nanoparticles

A Descriptive Cross-Sectional Study to Assess the Perception and Knowledge of Staff Nurses regarding Physical Restrains

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Open Journal of Nursing 2019年第3期9卷 239-248页

作者： Imad Fashafsheh salwa mohamed Ahmad Ayed Deyaaldeen ALRababah Nursing Department University of Bisha Bisha Saudi Arabia Nursing College Arab American University Jenin Palestine Nursing College Fayoum University Fayoum Egypt Alfarabi Colleges of Dentistry and Nursing Riyadh Saudi Arabia

Purpose: The purpose of this study was to examine the perceptions and knowledge regarding physical restraint used among registered nurses (RNs) and nursing assistants (NAs). method and Sample: A descriptive cross-sectional design was used. A convenient sample was recruited from nursing staff from Palestinian and Saudi Hospitals. Perceptions of Restraint Use Questionnaire (PRUQ) were used [1]. Results: A total of 144 nursing staffs were included. Physical restraint use was perceived as more important in some circumstances than others. In the critical care unit/ICU, the most important perceived reason for physical restraint use was protecting from falling out of bed and preventing removing dressing. There were significant differences of overall score for the PRUQ among all nursing staff according to hospital, t (142) = 8.74, P = 0.001. The mean of Saudi Arabia hospitals group (m = 4.56) was higher than the mean of Palestinian hospital group (m = 3.67). At the same time, there were significant differences of overall score for the PRUQ among all nursing staff according to specialized education in geriatrics, t (40) = 3.60, P = 0.001. The mean of no specialized education in geriatrics group (m = 4.13) was higher than the mean of yes specialized education in geriatrics group (m = 3.69). Conclusion and Implications: Nursing staff showed positive attitudes towards restrains application with difference between Palestinian and Saudi Arabian nurses. Proper implementation and good awareness of the complications are prerequisite for application of physical restrains for patients.

关键词： Perception Knowledge Nursing Staff Physical Restraints

不同结构AlGaN基深紫外发光二极管性能研究

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不同结构AlGaN基深紫外发光二极管性能研究

作者： ALmAZROI salwa SAAD H 北京化工大学

学位级别：硕士

基于AlGaN材料的深紫外发光二极管(DUV LED)具有体积小、能耗低、工作电流小、亮度高和发光响应速度快等优点,发光具有很强的杀菌效果,是汞灯的理想替代品,广泛地用于生物研究和污水处理领域。同时也可以为生物实验室、实验用器具及医... 详细信息

基于AlGaN材料的深紫外发光二极管(DUV LED)具有体积小、能耗低、工作电流小、亮度高和发光响应速度快等优点,发光具有很强的杀菌效果,是汞灯的理想替代品,广泛地用于生物研究和污水处理领域。同时也可以为生物实验室、实验用器具及医院手术室、医疗器具等消毒,在微制造技术和环境科学领域也大有可为,而且还可以用于制造侦测有毒粒子的传感器。由于其很容易与晶体管和集成电路配套使用,是近几年来迅速崛起的半导体光电器件。然而由于材料极化特性、器件结构等一系列因素,导致器件的性能难以与同族材料制备的可见光LED比拟,严重阻碍了其产业化进程。针对上述难题,本论文设计构建了系列DUV LED器件结构,并采用APSYS软件,研究了有源区结构、电子阻挡层结构及p型区结构对器件性能的影响机理,并对器件结构进行了优化设计,获得了以下研究成果。(1)深入研究了有源区结构对器件性能的影响,研究发现在一定范围内增加量子阱(QW)和量子阱势垒(QB)层厚度可以提高载流子注入效率和辐射复合效率,提升内部量子效率(IQE)和总功率。然而,超过一定阈值后,由于量子限制stark效应,导致IQE下降。在本工作中,当QW和QB的厚度分别为3.50、10.00 nm时,器件性能最佳。I-V曲线显示,QW和QB厚度的增加,对器件开启电压几乎没有影响。该研究强调了材料组成、能带对齐和厚度在器件性能优化方面的重要性。优化QW和QB层的厚度可以极大地提高内部量子效率(IQE)和LED总功率。(2)探讨了超晶格电子阻挡层(SL-EBL)对AlGaN DUV LED性能的影响。深入研究了SL-EBL厚度对器件功能的影响,揭示了结构参数和LED性能之间微妙的关系。研究表明,SL-EBL厚度的变化对AlGaN DUV LED的效率有重大影响,随着SL-EBL厚度的增加,IQE和总LED功率均呈现出一致的降低。在所有结构中,较薄的SL-EBL厚度为1.00 nm时可实现最佳性能。此外,分析还探讨了SL-EBL结构和不同铝(Al)组分对SL-EBL性能的影响。对带隙能量的检查显示,较大的SL-EBL层导致导带和价带边缘发生显著变化,表明载流子限制增强,载流子迁移性降低。通过优化SL-EBL结构,可以达到更高的IQE,达到68.37%,强调了精心设计和组成在提高LED性能中的重要性。(3)研究探讨了p型层内Al化合物浓度的变化对器件特性的影响。审查了AlGaN DUV LED的Al比例与效率之间的相关性,以及它们各自的厚度。在优化Al浓度之后,确定了7).(6./7).(6.的配置,第一层厚度为10 nm,第二层厚度为10 nm,可以实现72.12%的内部量子效率(IQE)。该配置在注入电流为500 A/m时,还可实现144.24 W/m的输出功率。

关键词： AlGaN 发光二极管有源区 EBL AlGaN器件结

Development and Validation of Stability Indicating HPTLC Assay for Determination of Gemifloxacin mesylate in Dosage Forms

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American Journal of Analytical Chemistry 2015年第2期6卷 85-97页

作者： Ashraf m. mahmoud Noha N. Atia salwa R. El-Shabouri Wesam m. El-Koussi Department of Pharmaceutical Analytical Chemistry Faculty of Pharmacy Assiut University Assiut Egypt Department of Pharmaceutical Chemistry College of Pharmacy Najran University Najran KSA

Simple and sensitive stability-indicating high performance thin layer chromatography (HPTLC) assay was developed and validated for quantitative determination of the antibacterial drug, gemifloxacin mesylate (GFX) in presence of its degradation products and ambroxol hydrochloride. The chromatographic separation was performed on HPTLC precoated silica gel plate 60F254 as stationary phase. The mobile phase consisted of a mixture of ethyl acetate: methanol: 25% ammonia, (8:4.5:3, v/v/v). The detection was performed using fluorescence mode and the emission intensity was measured using optical filter K400 after excitation at 342 nm. The Rf value for GFX was 0.47 ± 0.03. Good correlation coefficient was obtained over the concentration range of 1.5 - 180 ng/band. The LOD and LOQ of the proposed method were 0.28 and 0.86 ng/band, respectively. The proposed method was successfully applied for the analysis of GFX in its single and combined dosage forms. moreover, it was utilized to investigate the kinetics of acidic, alkaline, neutral, oxidative and photolytic degradation of the drug. The apparent kinetic-order rate constants and half-life times of the degradation process were calculated. Furthermore, the proposed method was successfully applied for investigating the factors affecting the storage of GFX.

关键词： HPTLC Gemifloxacin mesylate Stability Indicating Assay Kinetics Degradation Pharmaceutical Preparations

Design, Synthesis and Cancer Cell Line Activities of Pyrazolo[3,4-<i>b</i>]pyridine Derivatives

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Open Journal of medicinal Chemistry 2012年第3期2卷 78-88页

作者： mosaad Sayed mohamed Yara Essam El-Deen Awad salwa m. El-Hallouty moustafa El-Araby Pharmaceutical Organic Chemistry Department Faculty of Pharmacy Helwan University Cairo Egypt Pharmacognosy Department National Research Centre Giza Egypt

Starting from 4,6-dimethyl-2-oxo-(1H)-3-pyridinecarbonitrile 1 and 3-aminopyrazolopyridine 4, a series of cyanopyri- dine derivatives 3a-i, Schiff bases 5a-f, urea and thiourea derivatives 6a-b, amide derivatives 7a-h, pyridopyra- zolopy-rimidine 8a-b and pyridopyrazolotriazine 10a-b were synthesized. Activities of eleven representative compounds were evaluated against A-549 (lung), HEPG2 (liver) and HCT-116 (colon) cancer cell lines. The findings revealed that some of the synthesized compounds showed remarkable anticancer activities, especially 8b which displayed the highest activity among the tested compounds with IC50 equal to 2.9, 2.6 and 2.3 μmol. In addition to synthesis and biological activities, we present discussion about the rationale of the design and activity of the potent compound 8b using struc- ture-based modeling tools.

关键词： Pyridine Pyrazolopyridine Anticancer Activity CDK Inhibitors Kinase Inhibitor

Antimicrobial Activity of <i>Cannabis sativa</i>L.

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Chinese medicine 2012年第1期3卷 61-64页

作者： Esra m. m. Ali Aisha Z. I. Almagboul salwa m. E. Khogali Umelkheir m. A. Gergeir Department of Biochemistry Nutrition and Toxicology Central Veterinary Research Laboratories Khartoum Sudan Department of microbiology and Parasitology Medicinal and Aromatic Plants Research Institute National Centre for Research Khartoum Sudan epartment of microbiology and Parasitology Medicinal and Aromatic Plants Research Institute National Centre for Research Khartoum Sudan

The oil of the seeds, petroleum ether and methanol extracts of the whole plant of Cannabis sativa belonging to the family Cannabinaceae were screened for their antimicrobial activity against two Gram positive organisms (Bacillus subtilis, Staphylococcus aureus), two Gram negative organisms (Escherichia coli, Pseudomonas aeruginosa) and two fungi namely Aspergillus niger and Candida albicans using the cup plate agar diffusion method. The oil of the seeds of Cannabis sativa exerted pronounced antibacterial activity (21 - 28 mm) against Bacillus subtilis and Staphylococcus aureus, moderate activity (15 mm) against Escherichia coli and high activity (16 mm) against Pseudomonas aeruginosa and inactive against the two fungi tested. The petroleum ether extract of the whole plant exhibited pronounced antibacterial activity (23 - 28 mm) against both Bacillus subtilis and Staphylococcus aureus organisms, high activity (16 mm) against Escherichia coli and inactive against Pseudomonas aeruginosa and both fungi. The methanol extract of the whole plant showed also pronounced antibacterial activity (29 mm) against Bacillus subtilis, low activity (12 mm) against Staphylococcus aureus and high activity (16 - 18 mm) against both Gram negative organisms, inactive against Aspergillus niger and low activity (13 mm) against Candida albicans. The minimum inhibitory concentrations of Cannabis sativa methanol extracts of the seeds and the whole plant against the standard organisms were determined using the agar plate dilution method. The standard organisms were tested against reference antibacterial and antifungal drugs and the results were compared with the activity of the extracts.

关键词： Antimicrobial Cannabis sativaSeeds Whole Plant methanol Extract Petroleum Ether Extract

Chemical Composition, Characterization and Factors Affecting Household Dust (<20 µm) in Greater Cairo, Egypt

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Open Journal of Air Pollution 2015年第4期4卷 184-197页

作者： salwa K. Hassan Ahmed A. El-Abssawy mamdouh I. Khoder Air Pollution Department National Research Centre Giza Egypt Environmental Sciences Department Faculty of Meteorology Environment and Arid Land Agriculture King Abdulaziz University Jeddah Saudi Arabia Center of Excellence in Environmental Studies King Abdulaziz University Jeddah Saudi Arabia

Adverse health and environmental effects of household dust are derived from their chemical composition and properties. In this study, household, stairs and entryway dust (<20 μm) samples from homes located in urban, ... 详细信息

Adverse health and environmental effects of household dust are derived from their chemical composition and properties. In this study, household, stairs and entryway dust (m) samples from homes located in urban, residential and residential near to industrial area in Greater Cairo during summer 2013 were collected to study their chemical composition, characterization and factors affecting them. Results indicate that the levels of measured anions and cations were higher in the household compared to stairs and entryway dust. The highest concentration of ?, , Cl-?,?, Na+, K+, Ca2+ and mg2+ in the household and entryway dust was found in urban area. was abundant in household, entryway and stairs dust followed by Cl- and . Its average concentrations were 21.38, 14.57 and 15.83 mg/g, respectively. The household/entryway (I/O) concentration ratios of measured ion components indicate that these species might derive from indoor sources, although outdoor sources could be present as well. pH values of household, stairs and entryway dust ranged from 6.43 to 8.53, indicating that these dusts brought a large amount of crustal species, and might alleviate the tendency of acidification. The relationships between the concentrations of acidic components ( and ) and basic components (, Ca2+ and mg2+) in household, stairs and entryway dust confirm that the acidity of dust is neutralized. Ca2+ and in household and stairs dust and Ca2+ and mg2+ in entryway dust are the most dominant neutralization substances.

关键词： Household Stairs and Entryway Dust Chemical Composition and Characterization Greater Cairo Egypt