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Journal of Central South University 2020年第11期27卷 3175-3187页

作者： Mustafa Khaleel IBRAHIM safaa najah saud Esah HAMZAH Engku Mohamad NAZIM Faculty of Computer Engineering University of Imam Jafar Sadeq Maysan BranchMaysan 62012Iraq Faculty of Information Sciences and Engineering Management&Science University40100 Shah AlamSelangorMalaysia Faculty of Mechanical Engineering Universiti Teknologi Malaysia81310 UTM Johor BahruJohorMalaysia

In the present study,the thermal,mechanical,and biological properties of xAg/Ti-30Ta(x=0,0.41,0.82 and 2.48 at%)shape memory alloys(SMAs)were *** study was conducted using optical and scanning electron microscopy(SEM),X-ray diffractometry(XRD),compression test,and shape memory *** xAg/Ti-Ta was made using a powder metallurgy technique and microwave-sintering *** results revealed that the addition of Ag has a significant effect on the pore size and shape,whereas the smallest pore size of 11μm was found with the addition of 0.41 at%along with a relative density of 72%.The fracture stress and strain increased with the addition of Ag,reaching the minimum values around 0.41 at%***,this composition showed the maximum stress and strain at fracture ***,0.82 Ag/Ti-Ta shows more excellent corrosion resistance and biocompatibility than other percentages,obtaining almost the same behaviour of the pure Ti and Ti-6Al-4V alloys,which can be recommended for their promising and potential response for biomaterial applications.

关键词： porous xAg/Ti-Ta shape memory alloys(SMAs) microwave sintering process microstructure characteristics mechanical properties and corrosion behavior bioactivity

Microwave sintering effects on the microstructure and mechanical properties of Ti–51at%Ni shape memory alloys

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International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 280-288页

作者： Mustafa K. Ibrahim E. Hamzah safaa N. saud E. N. E. Abu Bakar A. Bahador Faculty of Mechanical Engineering Universiti Teknologi Malaysia 81310 UTM Johor Bahru Johor Malaysia Faculty of Information Sciences and Engineering Management & Science University Shah Alam Selangor Malaysia

Ti–51at%Ni shape memory alloys(SMAs) were successfully produced via a powder metallurgy and microwave sintering *** influence of sintering parameters on porosity reduction,microstructure,phase transformation temperatures,and mechanical properties were investigated by optical microscopy,field-emission scanning electron microscopy(FE-SEM),X-ray diffraction(XRD),differential scanning calorimetry(DSC),compression tests,and microhardness *** the microwave temperature and holding time was found to strongly affect the density of porosity,presence of precipitates,transformation temperatures,and mechanical *** lowest density and smallest pore size were observed in the Ti–51at%Ni samples sintered at 900°C for 5 min or at 900°C for 30 *** predominant martensite phases of β2 and β19′ were observed in the microstructure of Ti–51at%Ni,and their existence varied in accordance with the sintering temperature and the holding *** the DSC thermograms,multi-transformation peaks were observed during heating,whereas a single peak was observed during cooling;these peaks correspond to the presence of the β2,R,and β19′ *** maximum strength and strain among the Ti–51at%Ni SMAs were 1376 MPa and 29%,respectively,for the sample sintered at 900°C for 30 min because of this sample's minimal porosity.

关键词： titanium nickel alloys shape memory effect powder metallurgy (PM) microwave heating sintering microstructure mechanical properties

In vitro microbiologically-induced concrete corrosion behavior of Ag^(+) loaded zeolite-polyurethane coating for concrete sewer applications

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Journal of Central South University 2022年第9期29卷 3171-3185页

作者： Asma KAMARUL ASRI safaa N.saud Esah HAMZAH Zaharah IBRAHIM Faculty of Mechanical Engineering Universiti Teknologi MalaysiaSkudai 81310Malaysia Faculty of Information Sciences and Engineering Management&Science UniversityShah Alam 40100Malaysia Faculty of Bioscience and Bioengineering Universiti Teknologi MalaysiaJohor 81310Malaysia

Microbiologically-induced concrete corrosion(MICC)refers to chemical reactions between biologically produced sulphuric acid and with hydration products in the hardened concrete paste,resulting in an early reduction of strength,deterioration,and very severe circumstances,structural *** paper explores the bactericidal characteristics of cementitious materials with surface coated with modified *** zeolite-polyurethane coating incorporated with silver was studied in environments inoculated with *** bacteria for 8 consecutive *** antibacterial characteristics were evaluated in terms of pH,optical density(OD),sulphate production and bacteria count to determine the effectiveness of the zeolite-polyurethane coatings in environments inoculated with *** bacteria producing the sulphuric *** results revealed that the samples incorporated with silver modified zeolites generally showed antibacterial performance(regardless of the zeolite type)compared with unmodified polyurethane *** was evaluated by the lack of bacteria attachment and the deformed microcolonies on the sample surface,lag in pH reduction,increase in OD,and sulphate *** silver zeolites gained their antibacterial performance from the release of silver ions(Ag^(+))when the sample comes into contact with aqueous *** results in the inhibition of cell functions of the bacteria and subsequently causes cell damage.

关键词： microbiologically-induced corrosion cement zeolite A.thiooxidans silver ions

Parameter optimization of microwave sintering porous Ti-23%Nb shape memory alloys for biomedical applications

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Transactions of Nonferrous Metals Society of China 2018年第4期28卷 700-710页

作者： Mustafa K.IBRAHIM E.HAMZAH safaa N.saud E.M.NAZIM A.BAHADOR Faculty of Mechanical Engineering Universiti Teknologi Malaysia Faculty of Information Sciences and Engineering Management & Science University

Porous Ti-23%Nb(mole fraction)shape memory alloys(SMAs)were prepared successfully by microwave sintering with excellent outer finishing(without space holder).The effects of microwave-sintering on the microstructure,phase composition,phase-transformation temperature,mechanical properties and shape-memory effect were *** results show that the density and size of porosity vary based on the sintering time and temperature,in which the smallest size and the most uniform pore shape are exhibited with Ti-23%Nb SMA after being sintered at 900°C for 30 *** microstructure of porous Ti-Nb SMA consists of predominantα',α,andβphases in needle-like and plate-like morphologies,and their volume fractions vary based on the sintering time and ***βphase represents the largest phase due to the higher content ofβstabilizer element with little intensities ofαandα'*** highest ultimate strength and its strain are indicated for the sample sintered at 900°C for 30 min,while the best superelasticity is for the sample sintered at 1200°C for 30 *** low-elastic modulus enables these alloys to avoid the problem of“stress shielding”.Therefore,microwave heating can be employed to sinter Ti-alloys for biomedical applications and improve the mechanical properties of these alloys.

关键词： biomedical Ti-23%Nb alloy microwave sintering microstructure transformation temperature mechanical properties

Microstructure and superelastic properties of free forged Ti-Ni shape-memory alloy

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Transactions of Nonferrous Metals Society of China 2018年第3期28卷 502-514页

作者： Abdollah BAHADOR Esah HAMZAH Katsuyoshi KONDOH Tuty ASMA ABUBAKAR Farazila YUSOF Junko UMEDA safaa N.saud Mustafa K.IBRAHIM Faculty of Mechanical Engineering Universiti Teknologi Malaysia JWRI Osaka University Department of Mechanical Engineering Faculty of EngineeringUniversity of Malaya Faculty of Information Science and Engineering Management and Science University

Elemental titanium(Ti)and nickel(Ni)powders were consolidated by spark plasma sintering(SPS)to fabricate Ti-51%Ni(mole fraction)shape-memory alloys(SMAs).The objective of this study is to enhance the superelasticity of SPS produced Ti-Ni alloy using free forging as a secondary *** from two processes(with and without free forging)were compared in terms of microstructure,transformation temperature and *** results showed that,free forging effectively improved the tensile and shape-memory *** increased from 6.8%to 9.2%after *** maximum strain during superelasticity increased from 5%to 7.5%and the strain recovery rate increased from 72%to 92%.The microstructure of produced Ti-51%Ni SMA consists of the cubic austenite(B2)matrix,monoclinic martensite(B19′),secondary phases(Ti3Ni4,Ti2Ni and TiNi3)and oxides(Ti4Ni2O and Ti3O5).There was a shift towards higher temperatures in the martensitic transformation of free forged specimen(aged at 500°C)due to the decrease in Ni content of B2 *** is related to the presence of Ti3Ni4 precipitates,which were observed using transmission electron microscope(TEM).In conclusion,free forging could improve superelasticity and mechanical properties of Ti-51%Ni SMA.

关键词： shape-memory alloy superelasticity spark-plasma sintering free forging

Midwives and Nurses Compliance with Standard Precautions in Palestinian Hospitals

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Open Journal of Nursing 2016年第4期6卷 294-302页

作者： Imad Fashafsheh Ahmad Ayed Mahdiah Koni safaa Hussein Imad Thultheen AL-Farabi Colleges Dentistry-Medicine-Nursing Riyadh KSA Department of Nursing Arab American University Jenin Palestine Department of Nursing An-Najah National University Nablus Palestine

Midwives and nurses should use the standard precautions as the basic level of infection control precautions when delivering care to all patients, regardless of their presumed infection status. Therefore midwifes and nurses should have sound knowledge and compliance with standard precaution. Aim of the study: The study aimed to assess the level of the compliance of standard precautions among the midwives and nurses in the Palestinian Hospitals. Method: A cross sectional study was conducted from May to June 2015 on 81 midwives and nurses from Palestinian hospitals. The data were collected from labor rooms and postpartum departments of Palestinian hospitals. Data were collected using pretested questionnaire on 81 midwives and nurses selected by convenience sample. Results: The current study showed that the average of standard precautions knowledge level and compliance are 74.6% and 83.8% respectively. There are an association between age, education, work experience, and compliance with standard precautions at p p < 0.05 (0.191). Conclusion: The midwives and nurses in the current study for both knowledge and compliance have high level regarding standard precautions. There is an association between age, education, work experience, and compliance with standard precautions. Recommendations: Knowledge of midwives and nurses should be updated;the importance of latest evidence-based practices of infection control in continuing education/training program should be emphasized;and training programs for newly midwives and nurses about standard precaution and at regular intervals should be provided.

关键词： Nurses Midwives Compliance Standard Precautions