Electrochemical corrosion study of helium ions implanted Zircaloy-4 in chloride media

Rafique, Mohsin,Khan, Atika,Afzal, Naveed,Farooq, Ameeq,Imran, M. Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.3

In this work, an attempt is made to improve the electrochemical corrosion resistance of Zircaloy-4 by helium ions implantation. For this purpose, the Zircaloy-4 was implanted with 300 keV helium ions of fluences 1 × 10¹³, 1 × 10¹⁵, and 1 × 10¹⁶ ions-cm^-2 by using Pelletron Accelerator. Electrochemical tests of pristine and ion-implanted samples were performed in NaCl solution and their potentiodynamic polarization curves were obtained. The results showed enhancement of the corrosion resistance of Zircaloy-4 after helium ions implantation. The corrosion rate and current density of the material were significantly reduced by the helium implantation. The decrease in corrosion parameters was attributed to helium ions diffusion inside Zircaloy-4 that reduced the electrons flow from the samples.

Fabrication of Br doped ZnO nanosheets piezoelectric nanogenerator for pressure and position sensing applications

Rafique Sumera,Kasi Ajab Khan,Aminullah,Kasi Jafar Khan,Bokhari Muzamil,Zafar Shakoor 한국물리학회 2021 Current Applied Physics Vol.21 No.-

In this research, a unique strategy was developed to enhance the output performance of 2D ZnO nanosheets based piezoelectric nanogenerator (PENG). The Br doped 2D ZnO nanosheets were fabricated by facile hydrothermal method on nanoporous anodic aluminum oxide (AAO) template. Along with structural and optical characterization of Br doped 2D ZnO nanosheets, the electrical output performance of Br doped 2D ZnO PENG was demonstrated under external mechanical force. The corresponding output voltage of Br doped 2D ZnO nanosheets PENG reached to 8.82 V at 6HZ, which is 3 times higher than undoped ZnO nanosheets PENG. The output power density of Br doped 2D ZnO nanosheets PENG reached to 38.8962μWcm 2 at an external load resistanec of about 2 MΩ. The Br doping in ZnO nanosheets significantly increased the sensitivity of PENG for pressure sensing and the flexibility of PENG contribute in the application of position sensing.

Microstructural features and mechanical properties of 18 MeV He⁺ ions irradiated pure Zr

Rafique, M.,Chae, S.,Kim, Y.-S. WORLD SCIENTIFIC 2016 MODERN PHYSICS LETTERS B Vol.30 No.32

Don't Be Depth Charged by the Depth Gauge

Rafique, Bilal,Varghese, Jajini,Toft, Neil Korean Society of Plastic and Reconstructive Surge 2017 Archives of Plastic Surgery Vol.44 No.4

Hybrid neuromorphic system for automatic speech recognition

Rafique, M.A.,Lee, B.G.,Jeon, M. IET 2016 Electronics letters Vol.52 No.17

<P>A multilayer neural network, equipped with a two-memristors synapse, for speech recognition is proposed. The discussed neuromorphic neural network is a hybrid system which uses a Gaussian-Bernoulli restricted Boltzmann Machine (RBM) to transform the speech data into sparse encoded binary data. The sparse data is used to train a standard RBM, and a two-memristors synapse using AI/Pr0.7Ca0.3MnO3 memristor is used as a connection between the two layers of the RBM. The simulations are performed with the real memristor's behavioural data, for potentiation and depression, to adjust learn-able parameters of the neuromorphic RBM. Instead of hard coded representation of the data, memristive synapses follow the biological way of learning for plasticity by training with examples. Experimentation with the American common use vowels and its results assert the efficacy of the proposed architecture.</P>

A facile hydrothermal synthesis of highly luminescent NaYF₄:Yb³⁺/Er³⁺ upconversion nanoparticles and their biomonitoring capability

Rafique, Rafia,Baek, Seung Hoon,Phan, Le Minh Tu,Chang, Sung-Jin,Gul, Anam Rana,Park, Tae Jung Elsevier S.A. 2019 Materials Science and Engineering C Vol. No.

<P><B>Abstract</B></P> <P>Using a facile hydrothermal procedure, hydrophilic NaYF<SUB>4</SUB>: Yb<SUP>3+</SUP>/Er<SUP>3+</SUP> nanoparticles (NPs) have been prepared as lanthanide-doped upconversion (UC) materials exhibiting different morphologies, crystal phases and luminescence intensity. The upconversion nanoparticles (UCNP) were characterized by means of electron microscopy and spectroscopy, X-ray diffraction (XRD) and photoluminescence analysis. The molar concentration of reactants and volumes of NaF affect the shapes and uniformity of the synthesized NPs. These parameters also have influence on crystal phase and luminescence intensity of the NPs. Adjusting hydrothermal reaction time and dopant concentration also enable the synthesis of NPs with strong UC luminescence. The as-prepared UCNP showed cellular nontoxicity to HeLa cells, and thus they are capable as promising agents for biological imaging.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Fabrication of NaYF<SUB>4</SUB>:Yb<SUP>3+</SUP>/Er<SUP>3+</SUP>, upconversion nanoparticles (UCNPs) </LI> <LI> Molar concentration of NaF and reactants affects shapes and uniformity of nanoparticle. </LI> <LI> Adjusting reaction time and dopant concentration enhance UC luminescence of UCNPs. </LI> <LI> Optimized conditions are promising for <I>in vitro</I> HeLa cell imaging. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Dose-dependent physiological responses of <i>Triticum aestivum</i> L. to soil applied TiO₂ nanoparticles: Alterations in chlorophyll content, H₂O₂ production, and genotoxicity

Rafique, Rafia,Zahra, Zahra,Virk, Nasar,Shahid, Muhammad,Pinelli, Eric,Park, Tae Jung,Kallerhoff, Jean,Arshad, Muhammad Elsevier 2018 Agriculture, ecosystems & environment Vol.255 No.-

<P>Titanium dioxide nanoparticles (TiO2 NPs) are used widely in commercial products. These high production levels have led to their increased release into natural ecosystems, where they may interact with plants and affect their physiological functions. The aim of this study was to assess the physiological responses of wheat (Triticum aestivum L.) to increasing concentrations of TiO2 NPs. TiO2 NPs with a particle size less than 20 nm were administered as soil spiked with 0, 20, 40, 60, 80, and 100 mg TiO2 NPs kg(-1), and their physiological parameters, including root and shoot lengths, biomass, phytoavailability of phosphorus (P), chlorophyll content, H2O2 production, and micronuclei (MN) formation in the plants grown from seeds in NPs-spiked soils, were subsequently recorded. All experiments were repeated twice with four replicates per treatment. After 60 days exposure to the NPs, root and shoot lengths, and P uptake by plants was significantly (p < 0.05) higher between 20 and 60 mg kg(-1) compared to the control (0 mg kg(-1) TiO2 NPs), but was then lower at 80 and 100 mg kg(-1) compared to 60 mg kg(-1) TiO2 NPs. The application of TiO2 NPs led to chlorophyll content being higher by 32.3% at 60 mg kg(-1) than in the control, but 11.1% lower content was observed at 100 mg kg(-1). The results suggested that wheat could not tolerate concentrations of TiO2 NPs higher than 60 mg kg(-1) owing to over-production of H2O2 (84.4%) and MN formation (53.6%).</P>

Life table of cycad scale, Aulacaspis yasumatsui (Hemiptera: Diaspididae), reared on Cycas in Taiwan

Rafique Bailey,Po-Yung Lai,Ti- Chuan Hsu,Niann-Tai Chang 한국응용곤충학회 2010 Journal of Asia-Pacific Entomology Vol.13 No.3

Aulacaspis yasumatsui Takagi (Hemiptera: Diaspididae), an invasive scale insect, attacks different species of Cycas (Cycadales: Cycadaceae) in Taiwan. Development, survival and fecundity of A. yasumatsui were studied on Cycas taitungensis at 24 °C, 70±10% RH, and a photoperiod of 12:12 (L:D) h under laboratory conditions. Data on the life history of A. yasumatsui were analyzed using the age-stage, two-sex life table, to address variable development rates among individuals and between sexes. The egg incubation time was 7.26 days for both females and males and female nymphal development duration was 28.65 days. The development duration of male nymphal stages+pupal stage was 19 days. The total pre-oviposition period (TPOP) was 35.92 days. The maximum longevity of female adults was 67 days and 1 day for males. The intrinsic rate of increase (r) was 0.100 day-1, the finite rate of increase (λ) was 1.11 day-1, the net reproduction rate (Ro) was 111.51 offspring /individual, and the mean generation time (T) was 47.24 day. Life table data can be used to project population growth, to design mass rearing programs and to establish management tactics to control insect pests.

FREQUENCY OF COTTONSEED CAKE SUPPLEMENTATION FOR YEARLING HEIFERS ON BLUE GRAMA RANGE

Rafique, S.,Wallace, J.D.,Parker, G. Asian Australasian Association of Animal Productio 1992 Animal Bioscience Vol.5 No.2

Yearling replacement heifers were used in a two-year study at the Fort Stanton Experimental Ranch near Capitan, New Mexico, USA to compare frequency (once versus three times weekly) of feeding a cottonseed cake supplement. The study involved periods of 130 days (January 4 through May 14) in 1985, and 146 days (December 4 through April 29) in 1986. In each year, supplemental periods were just before the breeding season (natural breeding in multiple-sire groups) that lasted for 75 days during first year and 60 days during second year. During the first year, all (83) heifers (Angus $\times$ Hereford) were supplemented at a level equivalent to 45 kg/head daily and during second year, all (69) heifers (Angus $\times$ Hereford, Hereford) were fed at a level equivalent to .68 kg/head daily. In the first year, heifers were sorted by initial weight into two replications, i.e., those weighing under 223 kg were placed in replicate 1 and those weighing over 223 kg were placed in replicate 2. During the second year, heifers were sorted by breed into two replications, i.e., Angus $\times$ Hereford heifers were placed in replicate 1 and Hereford heifers in replicate 2. Each year, half of the heifers in each replication were supplemented once weekly and the other half three time weekly. Weight gains of heifers were similar for the two treatments over both years of study. During the first year, weight gains for heifers supplemented once or thrice weekly (.23 vs .21 kg daily, respectively) did not differ (p>.05) and the same trend for the second year (.15 vs .16 kg daily, respectively) was observed. Similarly, breeding performance was consistent with weight gains and no difference (p>.05) between treatments was observed either year. Lower conception rates during the second tear of study (92 vs 72% for years 1 and 2, respectively) were due mainly to involvement of Hereford heifers that had an average weight of 232 kg at the start of breeding season and conception rate of 54% (averaged across both supplemental treatments). Based on the combined results of both trials, frequency of supplementation did not affect growth rate of yearling heifers nor did it influence their subsequent conception rate.

Preoperative administration effect of metronidazole, ceftriaxone sodium and their combination on stenotic index of jejunal anastomotic segment of dogs

Rafique, Rehan,Asi, Muhammad Nadeem,Saqib, Muhammad,Hussain, Muhammad Hammad,Sial, Awais-ur-Rehman,Mushtaq, Aqsa The Korean Society of Veterinary Science 2014 大韓獸醫學會誌 Vol.54 No.1

The jejunum is the longest part of the small intestine and its lumen is mainly involved in the absorption of the nutrients. The present study was conducted to evaluate the effects of metronidazole, ceftriaxoine sodium and their combination on the stenotic index of the end to end jujunal anastomotic site. To accomplish this, 20 healthy stray dogs were subjected to end to end jejunal ansastmosis. Dogs in Group A (control) underwent jejunal anstomosis with no antibiotic prophylaxis, while those in Group B received surgery and metronidazole alone at 50 mg/kg, those in Group C received ceftriaxone sodium intravenously at 30 mg/kg body weight prior to surgery and dogs in Group D were given metronidazole in combination with ceftriaxone sodium at 50 mg/kg and 30 mg/kg, respectively, 2 h before surgical intervention. No significant difference (p > 0.05) in the stenotic index was observed at 14 days after jejunal anastomosis. These findings indicate that prophylactic administration of metronidazole and ceftriaxone sodium alone or in combination had no significant effect on the stenotic index of the jejunum.