Displaying publications 1 - 20 of 23 in total

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  1. Reduction of gain depletion and saturation on a Brillouin-erbium fiber laser utilizing a Brillouin pump preamplification technique
    Al-Mansoori MH, Mahdi MA
    Appl Opt, 2009 Jun 20;48(18):3424-8.
    PMID: 19543350
    This paper presents the characteristics of a multiwavelength L-band Brillouin-erbium comb fiber laser with a preamplified Brillouin pump (BP) power technique at low pumping powers. The issue of erbium-doped fiber gain depletion and Brillouin gain saturation are resolved by the proposed structure. For long single-mode fiber length, the Stokes line emission occurs at low pumping powers because of the high strength of spontaneous Brillouin scattering, which provides a strong seed for coherent regenerative amplification of the Stokes line in the laser cavity. The laser structure achieves a low threshold power of 17 mW and is able to produce high number of output channels at low pumping powers. We experimentally show that the fiber laser structure can produce up to 37 channels at 55 and 0.045 mW of 1480 nm pump and BP powers, respectively.
    Matched MeSH terms: Lasers, Solid-State
  2. Characterization of a multiwavelength Brillouin-erbium fiber laser based on a linear cavity configuration
    Al-Mansoori MH, Saharudin S, Abdul-Rashid H, Mahdi MA, Abdullah MK
    Appl Opt, 2005 May 10;44(14):2827-31.
    PMID: 15943335
    We experimentally demonstrate a simple method for generating a multiwavelength Brillouin comb by utilizing a linear cavity of hybrid Brillouin-erbium fiber lasers (BEFLs). The optimization of Brillouin pump wavelength, power, and erbium gain played a significant role in determining the maximum number of Brillouin Stokes signals generated. Simultaneous and stable multiple-wavelength laser output of 22 lines with 10.88-GHz channel spacing has been obtained with good flatness. Various parameters such as 980-nm pump power, Brillouin pump wavelength, and Brillouin pump power that affect the performance of a multiwavelength BEFL system have been investigated. An analysis of the tuning range of the system is presented.
    Matched MeSH terms: Lasers, Solid-State
  3. Optimization of output coupling ratio on the performance of a ring-cavity Brillouin-erbium fiber laser
    Hambali NA, Mahdi MA, Al-Mansoori MH, Saripan MI, Abas AF
    Appl Opt, 2009 Sep 20;48(27):5055-60.
    PMID: 19767918 DOI: 10.1364/AO.48.005055
    The operation of a single-wavelength Brillouin-erbium fiber laser (BEFL) system with a Brillouin pump preamplified technique for different output coupling ratios in a ring cavity is experimentally demonstrated. The characteristics of Brillouin Stokes power and tunability were investigated in this research. The efficiency of the BEFL operation was obtained at an optimum output coupling ratio of 95%. By fixing the Brillouin pump wavelength at 1550 nm while its power was set at 1.6 mW and the 1480 pump power was set to its maximum value of 135 mW, the Brillioun Stokes power was found to be 28.7 mW. The Stokes signal can be tuned within a range of 60 nm from 1520 to 1580 nm without appearances of the self-lasing cavity modes in the laser system.
    Matched MeSH terms: Lasers, Solid-State
  4. Fulltext Tuning range characteristics of linear cavity L-band multiwavelength brillouin-erbium fibre laser
    Al-Mansoori, M.H., Mahdi, M.A., Iqbal, S.J., Abdullah, M.K.
    ASM Science Journal, 2008;2(2):107-113.
    MyJurnal
    In this paper, the tuning range characteristics of a multiwavelength L-band Brillouin-erbium fibre laser utilizing a linear cavity is described. The dependency of the Stokes signal tuning range on the laser’s pumping power and single mode fibre length is elaborated. The proposed laser configuration exhibited a wide tuning range of 11 nm from 1599 nm to 1610 nm. The maximum number of 28 output channels with a spacing of 10.5 GHz was achieved by setting the Brillouin pump wavelength and power at 1603.1 nm and 1.1 mW, respectively. The wider tuning range and higher number of Brillouin Stokes contributed to the higher efficiency of doublepass amplification in the erbium gain medium and also to the bidirectional generation of Brillouin Stokes in the single-mode fibre.
    Matched MeSH terms: Lasers, Solid-State
  5. Multiwavelength Brillouin-erbium fiber laser with double-Brillouin-frequency spacing
    Shee YG, Al-Mansoori MH, Ismail A, Hitam S, Mahdi MA
    Opt Express, 2011 Jan 31;19(3):1699-706.
    PMID: 21368983 DOI: 10.1364/OE.19.001699
    We demonstrate a multiwavelength Brillouin-erbium fiber laser with double-Brillouin-frequency spacing. The wider channel spacing is realized by circulating the odd-order Stokes signals in the Brillouin gain medium through a four-port circulator. The circulated odd-order Stokes signals are amplified by the Brillouin gain and thus produce even-order Stokes signals at the output. These signals are then amplified by erbium gain block to form a ring-cavity laser. Ten channels with 0.174 nm spacing that are generated at 0.5 mW Brillouin pump power and 150 mW pump power at 1480 nm can be tuned from 1556 nm to 1564 nm. The minimum optical signal-to-noise ratio of the generated output channels is 30 dB with maximum power fluctuations of ±0.5 dB.
    Matched MeSH terms: Lasers, Solid-State*
  6. Widely tunable multi-wavelength Brillouinerbium fiber laser utilizing low SBS threshold photonic crystal fiber
    Mohd Nasir MN, Yusoff Z, Al-Mansoori MH, Abdul Rashid HA, Choudhury PK
    Opt Express, 2009 Jul 20;17(15):12829-34.
    PMID: 19654689
    A widely tunable low stimulated Brillouin scattering (SBS) photonic crystal fiber (PCF) based multi-wavelength Brillouin-erbium fiber laser is presented. The fiber laser structure utilizes a pre-amplified Brillouin pump (BP) technique with 100 m of PCF and a tunable band-pass filter within a Fabry-Perot cavity. A total of 14 Brillouin Stokes lines can be tuned over 29 nm from 1540 nm to 1569 nm. The wide tunability was only limited by the bandwidth of the tunable band-pass filter. A constant channel spacing of 0.079 nm and signal to noise ratio (SNR) of more than 20 dB for each Brillouin Stokes lines were also observed.
    Matched MeSH terms: Lasers, Solid-State
  7. Nanosecond soliton pulse generation by mode-locked erbium-doped fiber laser using single-walled carbon-nanotube-based saturable absorber
    Ismail MA, Harun SW, Zulkepely NR, Nor RM, Ahmad F, Ahmad H
    Appl Opt, 2012 Dec 20;51(36):8621-4.
    PMID: 23262603 DOI: 10.1364/AO.51.008621
    We demonstrate a simple and low cost mode-locked erbium-doped fiber laser (EDFL) operating in the nanosecond region using a single-walled carbon nanotube (SWCNT)-based saturable absorber (SA). A droplet of SWCNT solution is applied on the end of a fiber ferrule, which is then mated to another clean connector ferrule to construct an SA. Then the SA is integrated into a ring EDFL cavity for nanosecond pulse generation. The EDFL operates at around 1570.4 nm, with a soliton-like spectrum with small Kelly sidebands, which confirms the attainment of the anomalous dispersion. It produces a soliton pulse train with a 332 ns width, repetition rate of 909.1 kHz, an average output power of 0.31 mW, and energy of 0.34 nJ at the maximum pump power of 130.8 mW.
    Matched MeSH terms: Lasers, Solid-State
  8. Model of a multiple-line distributed-feedback dye laser
    Khan N
    Appl Opt, 2004 Jan 20;43(3):678-81.
    PMID: 14765930
    The theoretical basis for simultaneous oscillation of 2N - 3 laser lines is due to interference of N (for all even N > or = 2) pump beams in a distributed-feedback dye laser is described. Multiple gratings are produced in a dye solution by interference patterns of N/2 pairs of a frequency-doubled Nd:YAG laser. N/2 pairs of mutually time-delayed pulses induce multiple gratings of different periodicities, of which 2N - 3 gratings support oscillation of 2N - 3 lines and the remaining gratings, because of their larger periods, cannot support Bragg scattering. The maximum number of laser lines depends on the mutual delay between adjacent pairs of beams, coherence, states of polarization, pulse lengths, and of course the number of pulses. For three pairs of excitation beams derived from the same source through wave-front or amplitude phase division techniques, the output lasing lines varied from a minimum of three to a maximum of nine. This research was carried out by pumping of a dye solution with two, four, and six pulses, but the principle may be extended to multiple output lines, depending on the number of pump pulses and on the gain of the dye solution.
    Matched MeSH terms: Lasers, Solid-State
  9. Effect of Photodynamic therapy and Er,Cr: YSGG laser on bond strength of bleached enamel to composite resin
    Niazi FH, Qamar Z, Tanvir SB, Noushad M, Dossary OBA
    Photodiagnosis Photodyn Ther, 2021 Sep;35:102405.
    PMID: 34153543 DOI: 10.1016/j.pdpdt.2021.102405
    OBJECTIVE: The purpose of the present study was bleached enamel reversal using conventional ascorbic acid (AA) and contemporary methods including Photodynamic therapy (PDT), Er, Cr: YSGG (ECL) on bond integrity to composite resin.

    MATERIAL AND METHOD: Forty sound permanent mandibular premolars were collected from a dental clinical setting and disinfected. All forty samples were mounted vertically in a rubber mold exposing only the clinical crown. All samples were bleached using Opalescence Boost Professional Teeth Whitening. After the bleaching procedure, each sample was randomly allocated into four groups according to surface treatment. Samples in group 1 were treated with methylene blue photosensitizer (MBP). Samples in group 2 were exposed to 10% sodium ascorbate. Samples in group 3 were treated with Er, Cr: YSGG laser (ECL). Samples in group 4 were not treated (control). All Samples were treated with 37% phosphoric acid and a bonding agent was applied. A bulk-fill composite was cured to all specimens and all samples were treated in a thermocycler. Specimens were placed in a universal testing machine for shear bond strength (SBS) testing. Descriptive statistics were associated by analysis of variance (ANOVA) and Tukey's post hoc test maintaining level of significance (p<0.05) RESULTS: The lowest SBS scores were achieved in the bleached enamel (BE) group (15.25±1.745 MPa). Whereas, the highest bond integrity was attained by AA group (32.23±1.854 MPa). Samples treated with ECL (31.87±1.659 MPa) and AA (32.23±1.854) were comparable (p>0.05). Samples treated with PDT exhibited significantly different SBS (22.41±1.258) compared to other experimental groups CONCLUSION: ECL showed a reversal effect of BE compared to AA and has the potential to be used in clinical settings. BE reversal using MBP needs further investigation.

    Matched MeSH terms: Lasers, Solid-State*
  10. Fulltext 56 nm Wide-Band Tunable Q-Switched Erbium Doped Fiber Laser with Tungsten Ditelluride (WTe2) Saturable Absorber
    Ahmad H, Albaqawi HS, Yusoff N, Yi CW
    Sci Rep, 2020 Jun 17;10(1):9860.
    PMID: 32555280 DOI: 10.1038/s41598-020-66664-9
    A wide-band and tunable Q-switched erbium-doped fiber (EDF) laser operating at 1560.5 nm with a tungsten ditelluride (WTe2) saturable absorber (SA) is demonstrated. The semi-metallic nature of WTe2 as well as its small band gap and excellent nonlinear optical properties make it an excellent SA material. The laser cavity uses an 89.5 cm long EDF, pumped by a 980 nm laser diode as the linear gain while the WTe2 based SA generates the pulsed output. The WTe2 based SA has a modulation depth, non-saturable loss and saturation intensity of about 21.4%, 78.6%, and 0.35 kW/cm2 respectively. Stable pulses with a maximum repetition rate of 55.56 kHz, narrowest pulse width of 1.77 µs and highest pulse energy of 18.09 nJ are obtained at the maximum pump power of 244.5 mW. A 56 nm tuning range is obtained in the laser cavity, and the output is observed having a signal to noise ratio (SNR) of 48.5 dB. The demonstrated laser has potential for use in a large number of photonics applications.
    Matched MeSH terms: Lasers, Solid-State
  11. Tunable range enhancement of Brillouin-erbium fiber laser utilizing Brillouin pump pre-amplification technique
    Al-Mansoori MH, Mahdi MA
    Opt Express, 2008 May 26;16(11):7649-54.
    PMID: 18545472
    We demonstrate an enhanced multiwavelength L-band Brillouin-erbium fiber laser (BEFL), in which the Brillouin pump is pre-amplified before entering the single-mode fiber. The Brillouin pump pre-amplification provided by the Erbium-doped fiber has created higher intensity of Brillouin Stokes line generated in the single-mode fiber that leads to the homogenous gain saturation. Thus the built-up of self-lasing cavity modes is suppressed in a wider wavelength range. In contrary to the conventional linear-cavity BEFL, the number of output channels is enhanced within the same tuning range.
    Matched MeSH terms: Lasers, Solid-State*
  12. Fulltext The effect of laser repetition rate on the LASiS synthesis of biocompatible silver nanoparticles in aqueous starch solution
    Zamiri R, Zakaria A, Ahangar HA, Darroudi M, Zamiri G, Rizwan Z, et al.
    Int J Nanomedicine, 2013;8:233-44.
    PMID: 23345971 DOI: 10.2147/IJN.S36036
    Laser ablation-based nanoparticle synthesis in solution is rapidly becoming popular, particularly for potential biomedical and life science applications. This method promises one pot synthesis and concomitant bio-functionalization, is devoid of toxic chemicals, does not require complicated apparatus, can be combined with natural stabilizers, is directly biocompatible, and has high particle size uniformity. Size control and reduction is generally determined by the laser settings; that the size and size distribution scales with laser fluence is well described. Conversely, the effect of the laser repetition rate on the final nanoparticle product in laser ablation is less well-documented, especially in the presence of stabilizers. Here, the influence of the laser repetition rate during laser ablation synthesis of silver nanoparticles in the presence of starch as a stabilizer was investigated. The increment of the repetition rate does not negatively influence the ablation efficiency, but rather shows increased productivity, causes a red-shift in the plasmon resonance peak of the silver-starch nanoparticles, an increase in mean particle size and size distribution, and a distinct lack of agglomerate formation. Optimal results were achieved at 10 Hz repetition rate, with a mean particle size of ~10 nm and a bandwidth of ~6 nm 'full width at half maximum' (FWHM). Stability measurements showed no significant changes in mean particle size or agglomeration or even flocculation. However, zeta potential measurements showed that optimal double layer charge is achieved at 30 Hz. Consequently, Ag-NP synthesis via the laser ablation synthesis in solution (LASiS) method in starch solution seems to be a trade-off between small size and narrow size distributions and inherent and long-term stability.
    Matched MeSH terms: Lasers, Solid-State*
  13. Fulltext Effect of Nd:YAG, Er,Cr:YSGG Laser Irradiation, and Adjunctive Photodynamic Therapy on Push-Out Bond Strength of Zirconia Posts to Radicular Dentin
    Alshammary F, Karobari MI, Assiry AA, Marya A, Shaikh GM, Siddiqui AA, et al.
    Biomed Res Int, 2021;2021:5523242.
    PMID: 34036099 DOI: 10.1155/2021/5523242
    This study is aimed at assessing the influence of Nd:YAG, Er,Cr:YSGG laser irradiation, and adjunctive photodynamic therapy (aPDT) on the bond strength of zirconia posts to radicular dentin. Eighty extracted anterior teeth were randomly categorized into 4 groups (n = 20) based on varying laser irradiation treatments, i.e., conventional cleaning and shaping (CCS), Nd:YAG, Er,Cr:YSGG, and aPDT group, respectively. Using a cutting machine, the samples were prepared for push-out bond strength analysis; 4 sections (2 on each apical and cervical) of around 1 mm thickness were sectioned for all roots at a right angle to the long axis of the post. After making the space for the post, they were incorporated into the root system and were subjected to different laser treatments. The universal testing machine was utilized to assess the push-out bond strength, which had a defined 1 mm/minute crosshead speed until the failure was encountered. Specimens in the aPDT group (8.20 ± 2.14 MPa) demonstrated the highest mean push-out bond strength, whereas the lowest was shown by samples in the CCS group (7.08 ± 1.11 MPa). According to the independent t-test, the mean push-out bond strength scores of the cervical segments were higher as compared to the apical segments in research groups (p < 0.05). Overall, the adhesive type was the most frequently encountered failure mode in all of the experimental groups, with the least number of failures observed in aPDT treated teeth samples. In conclusion, the push-out bond strength to radicular dentin was not much influenced by Nd:YAG, Er,Cr:YSGG laser, and aPDT in comparison with CCS. Although statistically not significant, however, the application of aPDT provided better outcomes as compared to other research groups.
    Matched MeSH terms: Lasers, Solid-State*
  14. Photobiomodulation therapy on wound treatment subsequent to Q-switched Nd: YAG laser tattoo removal in rat model
    Imrigha NAA, Bidin N, Lau PS, Musa N, Zakaria N, Krishnan G
    J Biophotonics, 2017 Oct;10(10):1287-1291.
    PMID: 28464516 DOI: 10.1002/jbio.201600295
    Q-switched Nd: YAG laser is the most effective laser for tattoo removal. Photobiomodulation (PBM) therapy is an alternative method applied to accelerate the wound healing. This paper investigated the effects of PBM therapy using 808 nm diode laser on tattooed skin after laser tattoo removal. Forty-five rats were selected and tattooed with black ink on their dorsal, and then distributed into three groups. G0 was received non-laser irradiation. G1 was treated by laser tattoo removal using 1064 nm with energy density of 3.4 J/cm2 without PBM therapy, while G2 was treated daily with PBM therapy using 808 nm diode laser of 5 J/cm2 after a single session of laser tattoo removal. The effects of tattoo removal and healing progress of the wound were analyzed using histological studies. Findings showed 808 nm laser promotes the healing process through enhancing epithelialization and collagen deposition. Moreover, PBM therapy stimulated immune cells to improve phagocytosis process for removing the tattoo ink fragments effectively. The PBM therapy treated group was capable of improving the healing process and increasing the quality of skin following the laser tattoo removal. It was also found that stimulation of cellular function by PBM therapy increased tattoo clearance efficiency.
    Matched MeSH terms: Lasers, Solid-State*
  15. Fulltext Effect of sandblasting, silica coating, and erbium: Yttrium-Aluminum-Garnet laser treatment on the shear bond strength of self-adhesive resin cement to alumina ceramics
    Caglar I, Ates SM, Boztoprak Y, Aslan YU, Duymus ZY
    Niger J Clin Pract, 2018 Aug;21(8):1000-1007.
    PMID: 30074001 DOI: 10.4103/njcp.njcp_300_17
    Objective: The aim of this study was to investigate the different surface treatments on the bond strength of self-adhesive resin cement to high-strength ceramic.

    Materials and Methods: Ninety aluminum oxide ceramic (Turkom-Ceramic Sdn. Bhd., Kuala Lumpur, Malaysia) specimens were produced and divided into nine groups to receive the following surface treatments: control group, no treatment (Group C), sandblasting (Group B), silica coating (Group S), erbium: yttrium-aluminum-garnet (Er:YAG) laser irradiation at 150 mJ 10 Hz (Group L1), Er:YAG laser irradiation at 300 mJ 10 Hz (Group L2), sandblasting + L1 (Group BL1), sandblasting + L2 (Group BL2), silica coating + L1 (Group SL1), and silica coating + L2 (Group SL2). After surface treatments, surface roughness (SR) values were measured and surface topography was evaluated. Resin cement was applied on the specimen surface, and shear bond strength (SBS) tests were performed. Data were statistically analyzed using one-way ANOVA and Tukey's multiple comparisons at a significance level of P < 0.05.

    Results: Group S, SL1, and SL2 showed significantly increased SR values compared to the control group (P < 0.05); therefore, no significant differences were found among the SR values of Groups B, BL1, BL2, L1, and L2 and the control group (P > 0.05). Group S showed the highest SBS values, whereas the control group showed the lowest SBS values.

    Conclusion: Silica coating is the most effective method for resin bonding of high strength ceramic, but Er:YAG laser application decreased the effectiveness.

    Matched MeSH terms: Lasers, Solid-State*
  16. Laser-induced changes of in vitro erythrocyte sedimentation rate
    Al Musawi MS, Jaafar MS, Al-Gailani B, Ahmed NM, Suhaimi FM
    Lasers Med Sci, 2017 Dec;32(9):2089-2095.
    PMID: 28967036 DOI: 10.1007/s10103-017-2340-5
    The study of the effects of low-level laser (LLL) radiation on blood is important for elucidating the mechanisms behind the interaction of LLL radiation and biologic tissues. Different therapy methods that involve blood irradiation have been developed and used for clinical purposes with beneficial effects. The aim of this study was to compare the effects of different irradiation protocols using a diode-pumped solid-state LLL (λ = 405 nm) on samples of human blood by measuring the erythrocyte sedimentation rate (ESR). Human blood samples were obtained through venipuncture into tubes containing EDTA as an anticoagulant. Every sample was divided into two equal aliquots to be used as an irradiated sample and a non-irradiated control sample. The irradiated aliquot was subjected to a laser beam with a wavelength of 405 nm and an energy density of 72 J/cm2. The radiation source had a fixed irradiance of 30 mW/cm2. The ESR change was observed for three different experimental protocols: irradiated whole blood, irradiated red blood cells (RBCs) samples re-suspended in non-irradiated blood plasma, and non-irradiated RBCs re-suspended in irradiated blood plasma. The ESR values were measured after laser irradiation and compared with the non-irradiated control samples. Irradiated blood plasma in which non-radiated RBCs were re-suspended was found to result in the largest ESR decrease for healthy human RBCs, 51%, when compared with RBCs re-suspended in non-irradiated blood plasma. The decrease in ESR induced by LLL irradiation of the plasma alone was likely related to changes in the plasma composition and an increase in the erythrocyte zeta potential upon re-suspension of the RBCs in the irradiated blood plasma.
    Matched MeSH terms: Lasers, Solid-State*
  17. Fulltext Laser-fabricated castor oil-capped silver nanoparticles
    Zamiri R, Zakaria A, Abbastabar H, Darroudi M, Husin MS, Mahdi MA
    Int J Nanomedicine, 2011;6:565-8.
    PMID: 21698083 DOI: 10.2147/IJN.S16384
    Silver nanoparticles were fabricated by ablation of a pure silver plate immersed in castor oil. A Nd:YAG-pulsed Q-switch laser with 1064-nm wavelength and 10-Hz frequency was used to ablate the plate for 10 minutes. The sample was characterized by ultraviolet-visible, atomic absorption, Fourier transform-infrared spectroscopies, and transmission electron microscopy. The results of the fabricated sample showed that the nanoparticles in castor oil were about 5-nm in diameter, well dispersed, and showed stability for a long period of time.
    Matched MeSH terms: Lasers, Solid-State
  18. Fulltext Preparation of silver nanoparticles in virgin coconut oil using laser ablation
    Zamiri R, Azmi BZ, Sadrolhosseini AR, Ahangar HA, Zaidan AW, Mahdi MA
    Int J Nanomedicine, 2011;6:71-5.
    PMID: 21289983 DOI: 10.2147/IJN.S14005
    Laser ablation of a silver plate immersed in virgin coconut oil was carried out for fabrication of silver nanoparticles. A Nd:YAG laser at wavelengths of 1064 nm was used for ablation of the plate at different times. The virgin coconut oil allowed formation of nanoparticles with well-dispersed, uniform particle diameters that were stable for a reasonable length of time. The particle sizes and volume fraction of nanoparticles inside the solutions obtained at 15, 30, 45 min ablation times were 4.84, 5.18, 6.33 nm and 1.0 × 10(-8), 1.6 × 10(-8), 2.4 × 10(-8), respectively. The presented method for preparation of silver nanoparticles in virgin coconut oil is environmentally friendly and may be considered a green method.
    Matched MeSH terms: Lasers, Solid-State
  19. Fulltext In Vitro Mean Red Blood Cell Volume Change Induced by Diode Pump Solid State Low-Level Laser of 405 nm
    Musawi MS, Jafar MS, Al-Gailani BT, Ahmed NM, Suhaimi FM, Suardi N
    Photomed Laser Surg, 2016 May;34(5):211-4.
    PMID: 26966989 DOI: 10.1089/pho.2015.4043
    OBJECTIVE: This study was conducted to investigate the effects of low-level laser (LLL) doses on human red blood cell volume. The effects of exposure to a diode pump solid state (DPSS) (λ = 405 nm) laser were observed.

    BACKGROUND DATA: The response of human blood to LLL irradiation gives important information about the mechanism of interaction of laser light with living organisms. Materials and methods Blood samples were collected into ethylenediaminetetraacetic acid (EDTA)-containing tubes, and each sample was divided into two equal aliquots, one to serve as control and the other for irradiation. The aliquot was subjected to laser irradiation for 20, 30, 40, or 50 min at a fixed power density of 0.03 W/cm(2). Mean cell volume (MCV) and red blood cell (RBC) counts were measured immediately after irradiation using a computerized hemtoanalyzer.

    RESULTS: Significant decrease in RBC volume (p 

    Matched MeSH terms: Lasers, Solid-State
  20. Synthesis of Au-Ag Alloy Nanoparticles in Deionized Water by Pulsed Laser Ablation Technique
    Norsyuhada W, Shukri WM, Bidin N, Islam S, Krishnan G
    J Nanosci Nanotechnol, 2018 Jul 01;18(7):4841-4851.
    PMID: 29442664 DOI: 10.1166/jnn.2018.15358
    Au-Ag alloy nanoparticles are physically synthesized using rapid, simple and efficient Q-switched Nd:YAG pulsed laser ablation in liquid technique (PLAL). Au and Ag colloidal solutions are separately prepared by 1064 nm laser ablation of metallic target (gold and silver) which is immersed in deionized water. Au-Ag alloy nanoparticles are prepared by irradiating the mixture of Au and Ag colloidal solutions with 532 nm of second harmonic wavelength of Nd:YAG laser at three different ratio, 3:1, 1:1 and 1:3 within different exposure times. The three of plasmon absorption bands of Au-Ag nanoparticles are shifted linearly to the lower wavelength [499.67 nm (3:1), 481.25 nm (1:1), 467.91 nm (1:3)], as compared to plasmon absorption spectra of pure Au (520 nm) and Ag (400 nm). Moreover, the change in colors are also observed from red (Au) and yellow (Ag) to orange, brown and green color due to the Au-Ag alloy formations, respectively. Transmission electron microscopy shows the Ag shell around the inner core of Au spherical metal with broad size distribution due to the three different volume ratio, respectively (1.7 nm, 0.7 nm, 1.4 nm). Energy-dispersive X-ray spectroscopy analysis confirms the presence of Au and Ag elements in Au-Ag alloy nanoparticles without any contaminations. Attenuated total reflectance fourier transform infrared spectroscopy analysis also confirms the homogenous Au-Ag alloys chemical bonding.
    Matched MeSH terms: Lasers, Solid-State
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