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Fulltext Behavior of Tilted Angle Shear Connectors

Khorramian K, Maleki S, Shariati M, Ramli Sulong NH

PLoS One, 2015;10(12):e0144288.
PMID: 26642193 DOI: 10.1371/journal.pone.0144288

According to recent researches, angle shear connectors are appropriate to transfer longitudinal shear forces across the steel-concrete interface. Angle steel profile has been used in different positions as L-shaped or C-shaped shear connectors. The application of angle shear connectors in tilted positions is of interest in this study. This study investigates the behaviour of tilted-shaped angle shear connectors under monotonic loading using experimental push out tests. Eight push-out specimens are tested to investigate the effects of different angle parameters on the ultimate load capacity of connectors. Two different tilted angles of 112.5 and 135 degrees between the angle leg and steel beam are considered. In addition, angle sizes and lengths are varied. Two different failure modes were observed consisting of concrete crushing-splitting and connector fracture. By increasing the size of connector, the maximum load increased for most cases. In general, the 135 degrees tilted angle shear connectors have a higher strength and stiffness than the 112.5 degrees type.

Matched MeSH terms: Carmustine
Dual-prism interferometer for collimation testing

Hii KU, Kwek KH

Appl Opt, 2009 Jan 10;48(2):397-400.
PMID: 19137053

An air-wedge lateral-shear interferometer using two prisms is presented. With a variable shear, the interferometer is suitable for testing collimation of a wide range of beam sizes down to a few millimeters in diameter. No antireflection coatings are necessary. Collimation for a light source with short coherent length is also demonstrated.

Matched MeSH terms: Carmustine
Fulltext Mechanics Model for Simulating RC Hinges under Reversed Cyclic Loading

Shukri AA, Visintin P, Oehlers DJ, Jumaat MZ

Materials (Basel), 2016 Apr 22;9(4).
PMID: 28773430 DOI: 10.3390/ma9040305

Describing the moment rotation (M/θ) behavior of reinforced concrete (RC) hinges is essential in predicting the behavior of RC structures under severe loadings, such as under cyclic earthquake motions and blast loading. The behavior of RC hinges is defined by localized slip or partial interaction (PI) behaviors in both the tension and compression region. In the tension region, slip between the reinforcement and the concrete defines crack spacing, crack opening and closing, and tension stiffening. While in the compression region, slip along concrete to concrete interfaces defines the formation and failure of concrete softening wedges. Being strain-based, commonly-applied analysis techniques, such as the moment curvature approach, cannot directly simulate these PI behaviors because they are localized and displacement based. Therefore, strain-based approaches must resort to empirical factors to define behaviors, such as tension stiffening and concrete softening hinge lengths. In this paper, a displacement-based segmental moment rotation approach, which directly simulates the partial interaction behaviors in both compression and tension, is developed for predicting the M/θ response of an RC beam hinge under cyclic loading. Significantly, in order to develop the segmental approach, a partial interaction model to predict the tension stiffening load slip relationship between the reinforcement and the concrete is developed.

Matched MeSH terms: Carmustine
Fulltext Shear Response of Glass Fibre Reinforced Polymer (GFRP) Built-Up Hollow and Lightweight Concrete Filled Beams: An Experimental and Numerical Study

Kong SY, Wong LS, Paul SC, Miah MJ

Polymers (Basel), 2020 Oct 02;12(10).
PMID: 33023168 DOI: 10.3390/polym12102270

This paper investigated the static behaviour of glass fibre reinforced polymer (GFRP) built-up hollow and concrete filled built-up beams tested under four-point bending with a span-to-depth ratio of 1.67, therefore focusing their shear performance. Two parameters considered for hollow sections were longitudinal web stiffener and strengthening at the web-flange junction. The experimental results indicated that the GFRP hollow beams failed by web crushing at supports; therefore, the longitudinal web stiffener has an insignificant effect on improving the maximum load. Strengthening web-flange junctions using rectangular hollow sections increased the maximum load by 47%. Concrete infill could effectively prevent the web crushing, and it demonstrated the highest load increment of 162%. The concrete filled GFRP composite beam failed by diagonal tension in the lightweight concrete core. The finite element models adopting Hashin damage criteria yielded are in good agreement with the experimental results in terms of maximum load and failure mode. Based on the numerical study, the longitudinal web stiffener could prevent the web buckling of the slender GFRP beam and improved the maximum load by 136%. The maximum load may be further improved by increasing the thickness of the GFRP section and the size of rectangular hollow sections used for strengthening. It was found that the bond-slip at the concrete-GFRP interface affected the shear resistance of concrete-GFRP composite beam.

Matched MeSH terms: Carmustine
Fulltext Near Surface Mounted Composites for Flexural Strengthening of Reinforced Concrete Beams

Hosen MA, Jumaat MZ, Alengaram UJ, Islam ABMS, Bin Hashim H

Polymers (Basel), 2016 Mar 03;8(3).
PMID: 30979167 DOI: 10.3390/polym8030067

Existing structural components require strengthening after a certain period of time due to increases in service loads, errors in design, mechanical damage, and the need to extend the service period. Externally-bonded reinforcement (EBR) and near-surface mounted (NSM) reinforcement are two preferred strengthening approach. This paper presents a NSM technique incorporating NSM composites, namely steel and carbon fiber-reinforced polymer (CFRP) bars, as reinforcement. Experimental and analytical studies carried out to explore the performance of reinforced concrete (RC) members strengthened with the NSM composites. Analytical models were developed in predicting the maximum crack spacing and width, concrete cover separation failure loads, and deflection. A four-point bending test was applied on beams strengthened with different types and ratios of NSM reinforcement. The failure characteristics, yield, and ultimate capacities, deflection, strain, and cracking behavior of the beams were evaluated based on the experimental output. The test results indicate an increase in the cracking load of 69% and an increase in the ultimate load of 92% compared with the control beam. The predicted result from the analytical model shows good agreement with the experimental result, which ensures the competent implementation of the present NSM-steel and CFRP technique.

Matched MeSH terms: Carmustine
Fulltext Assessment of blurring effect and its associated factors by using imagej: a multiparameter double holes contrast-detail phantom study

Nur Farahana Pauzi, Zafri Azran Abdul Majid, Wan Muhamad Nasuha Wan Hussin, Abdul Halim Sapuan, Mohd Zulfaezal Che Azemin

International Journal of Allied Health Sciences, 2017;1(2):107-119.
MyJurnal

X-ray is produced in form of divergent beam. The beam divergence results to blurring effect that influences image diagnosis. Thus, the blurring effect assessment should be enrolled within the quality control (QC) program of an imaging unit.

Matched MeSH terms: Carmustine
Fulltext Software development for optimal design of different precast slabs

Noorzaei, J., Wong, J.N., Thanoon, W.A., Jaafar, M.S.

Pertanika Journal of Science & Technology, 2009;17(1):-.
MyJurnal

Precast concrete technology forms an important part in the drive towards a full implementation of the Industrialized Building System (IBS). The IBS requires building components and their dimensions to be standardized, and preferably cast off site. Slabs are major structural elements in buildings, other than beams and columns. Standardized and optimized slabs can significantly enhance the building industries in achieving the full implementation of the IBS. Nevertheless, this requires computer techniques to achieve standardized and optimized slabs which can satisfy all building design requirements, including the standards of architectural and structural design standards. This study proposed a computer technique which analysed and designed five different types of slabs which will satisfy all the requirements in design. The most commonly used slabs included in this study were the solid one way, solid two way, ribbed, voided and composite slabs. The computer techniques enable the design of the most optimized sections for any of the slab types under any loading and span conditions. The computer technique also provides details for the reinforcements required for the slabs.

Matched MeSH terms: Carmustine
Theoretical study of surface plasmons with phase singularities generated by evanescent Bessel beams

Al-awfi S

Sains Malaysiana, 2012;41:1461-1466.

We give details about how a surface plasmons with phase singularities can be produced when a Bessel beam light is totally reflected internally at the planar surface of a dielectric on which an infinitesimally thin film has been deposited. The characteristic property of such a light is the exponential decay with distance in a vacuum which can basically provide a two-dimensional surface plasmons with phase singularities with attractive enhancements. Such a phenomenon is governable by altering the incident angle and the order of the Bessel beam.

Matched MeSH terms: Carmustine
Effect of electron beam irradiation on natural rubber/linear low density polyethylene blends with m-phenylenebismaleimide

Nor Hayati Muhammad, Ibrahim Abdullah, Dahlan Mohd

Sains Malaysiana, 2011;40:1179-1186.

The effects of HVA-2 on radiation-induced cross-linkings in 60/40 natural rubber/ linear low density polyethylene (NR/LLDPE) blends was studied. NR/LLDPE was irradiated by using a 3.0 MeV electron beam machine with doses ranging from 0 to 250 kGy. Results showed that under the irradiation employed, the blends NR/LLDPE were cross-linked by the electron beam irradiation. The presence of HVA-2 in the blends caused the optimum dose to decrease and the blends to exhibit higher tensile properties. Further, within the dose range studied, the degradation caused by electron beam irradiation was found to be minimal. The optimized processing conditions were 120oC, 50 rpm rotor speed and 13 min processing time. The gel content, tensile strength, elongation at break, hardness and impact test studies were used to follow the irradiation-induced cross-linkings in the blend. For blends of 60/40 NR/LLDPE with 2.0 phr HVA-2, the optimum tensile strength and dose, were 19 MPa and 100 kGy, respectively. Blends of 60/40 NR/LLDPE without HVA-2, the optimum tensile strength and dose were 17.2 MPa and 200 kGy, respectively.

Matched MeSH terms: Carmustine
Fulltext The Tension-Stiffening Contribution of NSM CFRP to the Behavior of Strengthened RC Beams

Shukri AA, Darain KMU, Jumaat MZ

Materials (Basel), 2015 Jul 08;8(7):4131-4146.
PMID: 28793429 DOI: 10.3390/ma8074131

Tension stiffening is a characteristic behavior of reinforced concrete (RC) beams which is directly affected by the bond-slip property of steel bar and concrete interfaces. A beam strengthened with a near-surface mounted (NSM) technique would be even more affected by tension stiffening, as the NSM reinforcement also possess a bond-slip property. Yet assessing how much the tension stiffening of NSM contributes to the behavior of RC beams is difficult due to the fact that bond-slip effects cannot be directly incorporated into a strain-based moment-curvature analysis. As such, the tension stiffening is typically incorporated through various empirical formulations, which can require a great deal of testing and calibrations to be done. In this paper a relatively new method, which can be called the mechanics-based segmental approach, is used to directly simulate the tension stiffening effect of NSM reinforcements on RC beams, without the need for empirical formulations to indirectly simulate the tension stiffening. Analysis shows that the tension stiffening of NSM fiber reinforced polymer (FRP) contributes a significant portion to the stiffness and strength of the strengthened RC beam not only during serviceability, but at all load levels.

Matched MeSH terms: Carmustine
Fulltext Tapered Polymer Fiber Sensors for Reinforced Concrete Beam Vibration Detection

Luo D, Ibrahim Z, Ma J, Ismail Z, Iseley DT

Sensors (Basel), 2016 Dec 16;16(12).
PMID: 27999245 DOI: 10.3390/s16122149

In this study, tapered polymer fiber sensors (TPFSs) have been employed to detect the vibration of a reinforced concrete beam (RC beam). The sensing principle was based on transmission modes theory. The natural frequency of an RC beam was theoretically analyzed. Experiments were carried out with sensors mounted on the surface or embedded in the RC beam. Vibration detection results agreed well with Kistler accelerometers. The experimental results found that both the accelerometer and TPFS detected the natural frequency function of a vibrated RC beam well. The mode shapes of the RC beam were also found by using the TPFSs. The proposed vibration detection method provides a cost-comparable solution for a structural health monitoring (SHM) system in civil engineering.

Matched MeSH terms: Carmustine
Fulltext Evaluation of X-Ray Beam Quality Based on Measurements and Estimations Using SpekCalc and Ipem78 Models

Chen SC, Jong WL, Harun AZ

Malays J Med Sci, 2012 Jul;19(3):22-8.
PMID: 23610546 MyJurnal

Different computational methods have been used for the prediction of X-ray spectra and beam quality in diagnostic radiology. The purpose of this study was to compare X-ray beam qualities based on half-value layers (HVLs) determined through measurements and computational model estimations.

Matched MeSH terms: Carmustine
Fulltext Strengthening of RC Beams Using Externally Bonded Reinforcement Combined with Near-Surface Mounted Technique

Darain KMU, Jumaat MZ, Shukri AA, Obaydullah M, Huda MN, Hosen MA, et al.

Polymers (Basel), 2016 Jul 19;8(7).
PMID: 30974542 DOI: 10.3390/polym8070261

This study investigates the flexural behaviour of reinforced concrete (RC) beams strengthened through the combined externally bonded and near-surface mounted (CEBNSM) technique. The externally bonded reinforcement (EBR) and near-surface mounted (NSM) techniques are popular strengthening solutions, although these methods often demonstrate premature debonding failure. The proposed CEBNSM technique increases the bond area of the concrete⁻carbon fibre reinforced polymer (CFRP) interface, which can delay the debonding failure. This technique is appropriate when any structure has a narrow cross-sectional width or is in need of additional flexural capacity that an individual technique or material cannot attain. An experimental test matrix was designed with one control and five strengthened RC beams to verify the performance of the proposed technique. The strengthening materials were CFRP bar as NSM reinforcement combined with CFRP fabric as EBR material. The test variables were the diameter of the NSM bars (8 and 10 mm), the thickness of the CFRP fabrics (one and two layers) and the U-wrap anchorage. The strengthened beams showed enhancement of ultimate load capacity, stiffness, cracking behaviour, and strain compatibility. The ultimate capacity of the CEBNSM-strengthened beams increased from 71% to 105% compared to that of the control beam. A simulation method based on the moment-rotation approach was also presented to predict the behaviour of CEBNSM-strengthened RC beams.

Matched MeSH terms: Carmustine
Fulltext Strengthening the Structural Behavior of Web Openings in RC Deep Beam Using CFRP

Rahim NI, Mohammed BS, Al-Fakih A, Wahab MMA, Liew MS, Anwar A, et al.

Materials (Basel), 2020 Jun 22;13(12).
PMID: 32580327 DOI: 10.3390/ma13122804

Deep beams are more susceptible to shear failure, and therefore reparation is a crucial for structural reinforcements. Shear failure is structural concrete failure in nature. It generally occurs without warning; however, it is acceptable for the beam to fail in bending but not in shear. The experimental study presented the structural behavior of the deep beams of reinforced concrete (RC) that reinforces the web openings with externally connected carbon fiber reinforced polymer (CFRP) composite in the shear zone. The structural behavior includes a failure mode, and cracking pattern, load deflection responses, stress concentration and the reinforcement factor were investigated. A total of nine reinforced concrete deep beams with openings strengthened with CFRP and one control beam without an opening have been cast and tested under static four-point bending load till failure. The experimental results showed that the increase the size of the opening causes an increase in the shear strength reduction by up to 30%. Therefore, the larger the openings, the lower the capability of load carriage, in addition to an increase in the number of CFRP layers that could enhance the load carrying capacity. Consequently, utilization of the CFRP layer wrapping technique strengthened the shear behavior of the reinforced concrete deep beams from about 10% to 40%. It was concluded that the most effective number of CFRP layers for the deep beam with opening sizes of 150 mm and 200 mm were two layers and three layers, respectively.

Matched MeSH terms: Carmustine
Fulltext Surface marker-assisted for orbital navigation surgery: a dry skull study

Nazimi, A.J., Nuraudi Zafirah, A.R., Nur Syaira, I., Izhar, A.A., Muhd Fazlynizam, R.

Medicine & Health, 2020;15(1):237-249.
MyJurnal

Tujuan kajian ini adalah untuk menerokai kaedah pembantu penanda permukaan terhadap implan orbital untuk pembedahan tulang orbit. Enam tengkorak manusia dewasa kering telah digunakan dalam kajian ini. Implan orbital aluminium yang disediakan secara individu, dengan ketebalan 0.4 mm disediakan untuk lantai orbit secara bilateral. Empat penanda permukaan implan fizikal dari aspek anterior dan posterior implan yang disediakan dan diimbas secara optik. Pemeriksaan pra-pembedahan tomografi berkomputer ‘cone-beam’ (CBCT) diperolehi untuk semua lantai orbit. Data 'Digital Imaging and Communications in Medicine' (DICOM) tengkorak diambil, diimport dan direka bentuk dengan format data stereolithografi (STL) implan orbital masing-masing menggunakan iPlan CMF (Versi 3.0, BrainLab, Jerman). Teknik gabungan imej dilakukan untuk setiap tengkorak selepas pembinaan semula dengan pengambilan pos-pembedahan CBCT. Pengukuran berasaskan daripada data tomografi terhadap posisi implant kemudian dinilai di antara kedudukan implan yang direncanakan dan yang direalisasikan dalam satah sagittal dan coronal. Analisa statistik dijalankan menggunakan Statistik Statistik PASW® 18. Hasil kajian menunjukkan bahawa 38 daripada 48 penanda permukaan yang dinilai menunjukkan peningkatan ketinggian kedudukan dalam skala kecil pasca-pembedahan berbanding dengan kedudukan implan orbital maya. Semakan metrik Euclidean menunjukkan perbezaan yang kurang daripada 1.00 mm dalam semua penanda permukaan kecuali pada kawasan lej posterior dan anterior dalam penilaian satah sagittal. Kajian ini menunjukkan bahawa penempatan penanda permukaan terhadap implant orbit dalam pembedahan navigasi orbit menyumbang kepada kedudukan implan orbital secara konsisten.

Matched MeSH terms: Carmustine
Fulltext An experiment of using x-ray microtomography (XMT) to study the depth of bonding agent penetration into dentinal tubules

Norzaiti Mohd Kenali

International Medical Journal Malaysia, 2017;16(21):60-60.
MyJurnal

This is a novel study of the depth of penetration of bonding agents (BA) by using a
miniaturised CT-scan, XMT.The Linear Attenuation Coefficient describes the fraction of a beam of
x-rays or gamma rays that is absorbed or scattered per unit thickness of the absorber. The higher
the LAC, the more opaque the image is. (Copied from article).

Matched MeSH terms: Carmustine
Discharge based processing systems for nitric oxide remediation

Hashim S, Wong C, Abas M, Dahlan K

Sains Malaysiana, 2010;39.

An electron beam (EB) flue gas test rig and a dielectric barrier discharge (DBD) reactor were tested for the removal of nitric oxide (NO) from gas stream in separate experiments. In both systems, energised electrons were used to produce radicals that reacted with the pollutants. The EB system was a laboratory scale test rig used to treat emission from a diesel run generator. At 1.0 MeV and 10 mA more than 90% NO removal from flue gases flowing at 120 Nm3/h can be achieved. For higher removal percentage, higher beam current was required. In a related effort, a table top, two tubes DBD reactor was used to process bottled gases containing 106 ppm NO. Total removal (>99%) was achieved when the inlet gas contained only NO and N2. Additional SO2 in the in let gas stream lowered the removal rate but was overcame by scaling up the system to 10 DBD tubes. The system was operated with input AC voltage of 35 kV peak to peak. In the EB treatment system, the amount of NO2 increased at high beam current, showing that the NO was also oxidised in the process. Whereas in the DBD reactor, the amount of NO2 remained insignificant throughout the process. This leads to the conclusion that the DBD reactor is capable of producing total removal of NO. This is highly desirable as post treatment will not be necessary.

Matched MeSH terms: Carmustine
Fulltext Preparation and characterization of hydrogels from grafting of vinyl pyrrolidone onto carboxymethyl cellulose

Ahmad, M.B., Hashim, K.B., Mohd Yazid, N., Zainuddin, N.

Pertanika Journal of Science & Technology, 2012;20(2):425-433.
MyJurnal

In this work, hydrogels were prepared from carboxymethyl cellulose (CMC) and 1-vinyl-2-pyrrolidone(VP) by Electron Beam irradiation in the presence of N,N'-methylenebisacrylamide (BIS) as a crosslinkingagent. The parameters studied include stirring time and percentage of crosslinking agent. Hydrogels werecharacterized using Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy(SEM). VP and BIS were found be effective as reinforcement materials to improve the properties ofCMC. Meanwhile, the optimum conditions were 5% BIS and 3 hours of stirring time. The gel fractionincreased when irradiation dose was increased. FTIR confirmed the crosslinking reaction between CMCand VP after the irradiation process by using BIS as the crosslinking agent. TGA thermograms showedchanges in the thermal properties of CMC-VP hydrogels in the presence of different amounts of BIS.

Matched MeSH terms: Carmustine
Histopathological effect of pterostilbene as chemoprevention in N-nitroso-tri-chloroethylurea (NTCU)-induced lung squamous cell carcinoma (SCC) mouse model

Surien O, Ghazali AR, Masre SF

Histol Histopathol, 2020 Oct;35(10):1159-1170.
PMID: 32893871 DOI: 10.14670/HH-18-247

BACKGROUND: Lung cancer is the leading cause of cancer-related deaths, and squamous cell carcinoma (SCC) is one of the most common types of lung cancer. Chemoprevention of lung cancer has gained increasing popularity as an alternative to treatment in reducing the burden of lung cancer. Pterostilbene (PS) may be developed as a chemopreventive agent due to its pharmacological activities, such as anti-proliferative, anti-inflammatory and antioxidant properties. This study aimed to investigate the effect of PS on the development of lung SCC in the mouse model.
METHODS: A total of 24 seven-week-old female Balb/C mice were randomly categorised into four groups, including two control groups comprising the N-nitroso-trischloroethylurea (NTCU)-induced lung SCC and vehicle control (VC) groups and two treatment groups comprising the 10mg/kg PS (PS10) and 50mg/kg PS (PS50) groups. All lung organs were harvested at week 26 for histopathological analysis.
RESULTS: All PS treatment groups showed chemopreventive activity by inhibiting the progression of lung SCC formation with PS10, resulting in mild hyperplasia, and PS50 was completely reversed in the normal bronchial epithelium layer compared with the VC group. PS treatment also reduced the expression of cytokeratin 5/6 in the bronchial epithelium layer. Both PS10 and PS50 significantly reduced the epithelium thickness compared to the NTCU group (p<0.05). PS is a potential chemopreventive agent against lung SCC growth by suppressing the progression of pre-malignant lesions and reducing the thickness of the bronchial epithelium.
CONCLUSIONS: The underlying molecular mechanisms of PS in lung SCC should be further studied.

Matched MeSH terms: Carmustine/analogs & derivatives
Fulltext NTCU induced pre-malignant and malignant stages of lung squamous cell carcinoma in mice model

Zakaria MA, Rajab NF, Chua EW, Selvarajah GT, Masre SF

Sci Rep, 2021 Nov 18;11(1):22500.
PMID: 34795360 DOI: 10.1038/s41598-021-01988-8

Mice have served as an excellent model to understand the etiology of lung cancer for years. However, data regarding dual-stage carcinogenesis of lung squamous cell carcinoma (SCC) remain elusive. Therefore, we aim to develop pre-malignant (PM) and malignant (M) lung SCC in vivo using N-nitroso-tris-chloroethylurea (NTCU). BALB/C mice were allotted into two main groups; PM and M groups which received treatment for 15 and 30 weeks, respectively. Then, the mice in each main group were allotted into three groups; control, vehicle, and cancer (n = 6), which received normal saline, 70% acetone, and 0.04 M NTCU by skin painting, respectively. Histopathologically, we discovered a mix of hyperplasia, metaplasia, and dysplasia lesions in the PM group and intracellular bridge; an SCC feature in the M group. The M group was positive for cytokeratin 5/6 protein which confirmed the lung SCC subtype. We also found significantly higher (P

Matched MeSH terms: Carmustine/analogs & derivatives*

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