Enhanced photocatalytic activity of N, P, co-doped carbon quantum dots: an insight from experimental and computational approach

Herein, we demonstrate the single-step microwave radiation assisted approach to develop Nitrogen (N) and Phosphorous (P) co-doped carbon quantum dots (NP-CQD). The developed NP-CQD showed enhancement in visible light photocatalytic activity towards methylene blue dye degradation than that of N-CQD and P-CQD due to creation of energy states and reduced work function as estimated by Ultraviolet photoelectron spectroscopy and corroborated by first-principles Density Functional Theory (DFT) calculations

Irradiation Effects on Microstructure and Dielectric Properties of Ba[(Mg0.32Co0.02)Nb0.66]O3 [BMCN] Thin Films

Ba[(Mg0.32Co0.02)Nb0.66]O3 [BMCN] thin films prepared on Pt-Si, MgO, Silicon and ITO coated glass substrates by Pulsed Laser Deposition Technique are investigated. Relative growth parameters suggest that ITO coated glass substrate has good potential for growing films with near Nano size columnar grains. In comparison to bulk, dielectric constant and dielectric loss increases in BMCN films. This undesirable rise in dielectric loss can be drastically reduced by a factor of more than 1/100th times through Ag15+ ion irradiation at 1 × 1012 ions/cm2 dose. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3025

Subcutaneous REGEN-COV Antibody Combination to Prevent Covid-19

BACKGROUND REGEN-COV (previously known as REGN-COV2), a combination of the monoclonal antibodies casirivimab and imdevimab, has been shown to markedly reduce the risk of hospitalization or death among high-risk persons with coronavirus disease 2019 (Covid-19). Whether subcutaneous REGEN-COV prevents severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and subsequent Covid-19 in persons at high risk for infection because of household exposure to a person with SARS-CoV-2 infection is unknown. METHODS We randomly assigned, in a 1:1 ratio, participants (=12 years of age) who were enrolled within 96 hours after a household contact received a diagnosis of SARSCoV- 2 infection to receive a total dose of 1200 mg of REGEN-COV or matching placebo administered by means of subcutaneous injection. At the time of randomization, participants were stratified according to the results of the local diagnostic assay for SARS-CoV-2 and according to age. The primary efficacy end point was the development of symptomatic SARS-CoV-2 infection through day 28 in participants who did not have SARS-CoV-2 infection (as measured by reverse-transcriptase- quantitative polymerase-chain-reaction assay) or previous immunity (seronegativity). RESULTS Symptomatic SARS-CoV-2 infection developed in 11 of 753 participants in the REGEN-COV group (1.5%) and in 59 of 752 participants in the placebo group (7.8%) (relative risk reduction [1 minus the relative risk], 81.4%; P104 copies per milliliter) was shorter (0.4 weeks and 1.3 weeks, respectively). No dose-limiting toxic effects of REGEN-COV were noted. CONCLUSIONS Subcutaneous REGEN-COV prevented symptomatic Covid-19 and asymptomatic SARS-CoV-2 infection in previously uninfected household contacts of infected persons. Among the participants who became infected, REGEN-COV reduced the duration of symptomatic disease and the duration of a high viral load

Amalgamation of Photostriction, Photodomain, and Photopolarization Effects in BaTiO3 and Its Electronic Origin

Multifunctional oxides offer huge potential for technological applications, owing to their inclusive physical properties such as ferroelectric, piezoelectric, and electro caloric properties. The natural occurrence of piezoelectricity, a tunable band gap of ferroelectrics, opens a path to study the light material interaction, leading to photoconduction and photovoltaic effects. Such light controlled devices yield additional advantages of weight reduction and wireless, remote controlled functionality over the heavy electric circuitry and, hence, are projected as an alternative solution to the traditional piezoelectric based devices. Among these materials, lead free BaTiO3 based ferroelectric materials are a good choice for their potential applications with recently discovered light controlled functionality. However, until now, the coupling of light with the chemistry of ferroelectricity of BaTiO3 crystals has been elusive, although the ferroelectricity and piezoelectricity are well studied. Here, the present study reports the photostrictive effect of the order of 10 4 on the dimension of the c domains of tetragonal BaTiO3 crystals and domain reorientation at room temperature under unpolarized, coherent visible light illumination, consequently resulting in enhancement in polarization. The electronic origin of domain evolution and photostriction is explained by the light induced modification in the Ti 3d O 2p hybridized orbitals. This facilitates the perspective of combining mechanical, electrical, optical, and functionalities in future generations of remote controlled device

Synthesis and Characterization of Vertically Aligned La0.7Sr0.3MnO3 NiO Nanocomposite Thin Films for Spintronic Applications

The microstructures and interfaces of two phase vertically aligned nanocomposite VAN thin films play a key role in the design of spintronic device architectures and their multifunctional properties. Here, we show how the microstructures in self assembled VAN thin films of La0.7Sr0.3MnO3 NiO LSMO NiO can be effectively tuned from nanogranular to nanocolumnar and to nanomaze by controlling the number of laser shots from the two constituent phase targets in the pulsed laser deposition PLD film growth. The observed microstructural induced strain is found to significantly enhance the magnetoresistance in a very broad temperature range between 10 and 240 K and to modulate the in plane exchange bias EB , with the largest EB value observed in the maximally strained heterostructures. Most interestingly, a unique perpendicular exchange bias PEB effect is also observed for these heterostructures with an enhanced PEB field of up to 230 Oe. X ray magnetic circular dichroism and training effect measurements demonstrate that the observed EB is disorder induced and arises due to the pinning of NiO uncompensated moments at the disordered interface which is ferromagnetically coupled with LSMO. Furthermore, systematic changes in the electronic structure across the vertical interface related to a variation of the Mn3 Mn4 content arise as a consequence of out of plane tensile strai

Electronic Depiction Of Magnetic Origin In Undoped And Fe Doped Tio 2-d Epitaxial Thin Films

We have investigated the electronic and magnetic properties of the pulsed laser deposited epitaxial thin films of undoped and Fe doped (4 at. ) anatase TiO2-d by photoemission, magnetization measurements, and ab-initio band structure calculations. These films show room temperature magnetic ordering. It is observed that Fe ions hybridize with the oxygen vacancy induced Ti3 defect states. Our study reveals the formation of local magnetic moment at Ti and Fe sites to be responsible for magnetic ordering. A finite density of states at the Fermi level in both undoped and Fe doped films is also observed, suggesting their degenerate semiconducting nature. © 2011 American Institute of Physics.9911Wang, P., Liu, Z., Lin, F., Zhou, G., Wu, J., Duan, W., Gu, B.-L., Zhang, S.B., (2010) Phys. Rev. B, 82, p. 193103. , 10.1103/PhysRevB.82.193103Khan, S.U.M., Al-Shahry, M., Ingler, Jr.W.B., (2002) Science, 297, p. 2243. , 10.1126/science.1075035Hong, N.H., Prellier, W., Sakai, J., Hassini, A., (2004) Appl. Phys. Lett., 84, p. 2850. , 10.1063/1.1695103Park, M.S., Kwon, S.K., Min, B.I., (2002) Phys. Rev. B, 65, pp. 161201R. , 10.1103/PhysRevB.65.161201Shinde, S.R., Ogale, S.B., Das Sarma, S., Simpson, J.R., Drew, H.D., Lofland, S.E., Lanci, C., Browning, N.D., (2003) Phys. Rev. B, 67, p. 115211. , 10.1103/PhysRevB.67.115211Ogale, S.B., (2010) Adv. Mater., 22, p. 3125. , 10.1002/adma.200903891Ohsuki, T., Chainai, A., Eguchi, R., Matsunami, M., Takata, Y., Taguchi, M., Nishino, Y., Shin, S., (2011) Phys. Rev. Lett., 106, p. 047602. , 10.1103/PhysRevLett.106.047602Sundaresan, A., Bhargavi, R., Rangarajan, N., Siddesh, U., Rao, C.N.R., (2006) Phys. Rev. B, 74, p. 161306. , 10.1103/PhysRevB.74.161306Hong, N.H., Sakai, J., Poirot, N., Brizé, V., (2006) Phys. Rev. B, 73, p. 132404. , 10.1103/PhysRevB.73.132404Pandey, S.K., Choudhary, R.J., (2011) J. Phys.: Condens. Matter., 23, p. 276005. , 10.1088/0953-8984/23/27/276005Wang, Z., Wang, W., Tang, J., Tung, L.D., Spinu, L., Zhou, W., (2003) Appl. Phys. Lett., 83, p. 518. , 10.1063/1.1593825Coey, J.M.D., Venkatesan, M., Fitzgerald, C.B., (2005) Nature Mater., 4, p. 173. , 10.1038/nmat1310Coey, J.M.D., Stamenov, P., Gunning, R.D., Venkatesan, M., Paul, K., (2010) New J. Phys., 12, p. 053025. , 10.1088/1367-2630/12/5/053025http://dx.doi.org/10.1063/1.3640212, See supplementary material at E-APPLAB-99-012138 for the experimental and computational detailsSanjines, R., Tang, H., Berger, H., Gozzo, F., Margaritondo, G., Levy, F., (1994) J. Appl. Phys., 75, p. 2945. , 10.1063/1.356190Prakash, R., Phase, D.M., Choudhary, R.J., Kumar, R., (2008) J. Appl. Phys., 103, p. 043712. , 10.1063/1.2885143Zhang, Z., Jeng, S.-P., Henrich, V.E., (1991) Phys. Rev. B, 43, p. 12004. , 10.1103/PhysRevB.43.12004Prakash, R., Choudhary, R.J., Phase, D.M., (2008) J. Phys.: Condens. Matter, 20, p. 335225. , 10.1088/0953-8984/20/33/335225Yang, K., Dai, Y., Huang, B., Feng, Y.P., (2010) Phys. Rev. B, 81, p. 033202. , 10.1103/PhysRevB.81.033202Kim, D., Hong, J., Park, Y.R., Kim, K.J., (2009) J. Phys.: Condens. Matter, 21, p. 195405. , 10.1088/0953-8984/21/19/195405Yoon, S.D., Chen, Y., Yang, A., Goodrich, T.L., Zuo, X., Arena, D.A., Ziemer, K., Harris, V.G., (2006) J. Phys.: Condens. Matter, 18, p. 355. , 10.1088/0953-8984/18/27/L0

Effect Of 200 mev Ag15+ Ion Irradiation On Structural And Magnetic Properties Of Mg0.95mn0.05fe2o4 Ferrite Thin Film

Nanocrystalline Mg0.95Mn0.05Fe2O4 ferrite thin films, prepared by pulsed laser deposition technique on a glass substrate coated with indium tin oxide, are irradiated with 200 MeV Ag15+ ions at different fluence values in the range from 1 × 1011 to 1 × 1012 ions/cm2. The as-deposited and irradiated thin films are investigated using X-ray diffraction, dc magnetization and atomic force microscopy techniques. X-ray diffraction analysis of the as-deposited as well as irradiated thin film indicates the single phase cubic structure as the main composition. The crystallite size evaluated from Scherrer's equation is found to be decreased from 26 nm for as-deposited thin films to 17 nm for irradiated at a fluence of 1 × 1012 ions/cm2. The decrease in crystallite size in all the thin film samples after irradiation indicates a distortion in the lattice structure caused by stress-induced defects. The zero-field-cooled (ZFC) and field-cooled (FC) magnetizations have been recorded in a low field of 100 Oe and they show a typical behavior of superparamagnetic particles. This is further supported by the magnetization hysteresis (M-H) curve taken at 300 K, for the as-deposited thin film, which shows zero coercivity and remanence. The blocking temperatures calculated from the maxima of ZFC are found to decrease with the increase in irradiation fluence, which is consistent with XRD results. © 2009 Elsevier B.V. All rights reserved.20317-1827072711Dash, J., Prasad, S., Venkataramani, N., Kishan, P., Kumar, N., Kulkarani, S.D., Date, S.K., (1999) J. Appl. Phys., 86, p. 3303Acarya, B.R., Krishan, R., Prasad, S., Venkataramani, N., Ajan, A., Shringi, N., (1994) Appl. Phys. Lett., 64, p. 1579Morisako, A., Matsumoto, M., Naoe, M., (1998) IEEE Trans. Magn., 24, p. 3024Hylton, T.L., Parker, M.A., Howard, J.K., (1992) Appl. Phys. Lett., 61, p. 867Sui, X., Kryder, M.H., (1993) Appl. Phys. Lett., 63, p. 1582Cho, H.S., Kim, M.H., Kim, H.J., (1994) J. Mater. Res., 9 (9), p. 2425Venzke, S., van Dover, R.B., Philips, J.M., Gyorgy, E.M., Siegrist, T., Chen, C.H., Werder, D., Opila, R., (1996) J. Mater. Res., 11 (5), p. 1187Kumar, R., Wasi Khan, M., Srivastava, J.P., Arora, S.K., Sofin, R.G.S., Choudhary, R.J., Shevets, I.V., (2006) J. Appl. Phys., 100, p. 100703Chrisey, D.B., Hubler, G.K., (1994) Pulsed Laser Deposition of Thin Films, , Wiley, New YorkNewman, H.S., Chrisey, D.B., Horwitz, J.S., Weaver, B.D., Reeves, M.E., (1991) IEEE Trans. Magn., 27, p. 2540Cotell, C.M., Chrisey, D.B., Grabowski, K.S., Sprague, J.S., Gossett, C.R., (1992) J. Biomaterials, 3, p. 87Carosella, C.A., Chrisey, D.B., Lubitz, P., Horwitz, J.S., Dorsey, P., Seed, R., Vitoria, C., (1992) J. Appl. Phys., 71, p. 5107Williams, C.M., Chrisey, D.B., Lubitz, P., Grabowski, K.S., Cotell, C.M., (1994) J. Appl. Phys., 75, p. 1676Neumeier, J.J., Hundley, M.F., Thompson, J.D., Heffner, R.H., (1995) Phys. Rev. B, 52, pp. R7006Ogale, A., Shinde, S.R., Kulkarani, V.N., Higgins, J., Choudhary, R.J., Kundaliya, D.C., Pelleto, T., Venkatesan, T., (2004) Phys. Rev. B, 69, p. 235101Ogale, S.B., Ghosh, K., Gu, J.Y., Shreekala, R., Shinde, S.R., Downes, M., Rajeswari, M., Mehta, G.K., (1988) J. Appl. Phys., 84, p. 6255Studer, F., Toulmonde, M., (1992) Nucl. Instrum. Methods B, 65, p. 560Houpert, C., Studer, F., Groult, D., Toulmonde, M., (1989) Nucl. Instrum. Methods B, 39, pp. 720Y723Kumar, R., Samantra, S.B., Arora, S.K., Gupta, A., Kanjilal, D., Pinto, R., Narlikar, A.V., (1998) Solid State Commun., 106 (12), pp. 805Y810Kumar, R., Arora, S.K., Kanjilal, D., Mehta, G.K., Bache, R., Date, S.K., Shinde, S.R., Patil, S.I., (1999) Radiat. Eff. Defects Solids, 147, p. 187Studer, F., Houpert, C.h., Groult, D., Fan, J.Y., Meftah, A., Toulemonde, M., (1993) Nucl. Instrum. Methods B, 82, p. 9

Irradiation Induced Texturing In The Mg0.95mn0.05fe2o4 Ferrite Thin Film

We present a study on the effect of swift heavy ions irradiation on the structural and magnetic properties of Mg0.95Mn0.05Fe2O4 ferrite thin film grown by pulsed laser deposition technique. X-ray diffraction (XRD) pattern of the as-deposited film reveals a cubic spinel structure with an intermediate phase of α-Fe2O3. This impurity phase completely dissolves upon irradiation with 200 MeV Ag15+-ions and it exhibits a strong crystallographic texture along the (440) plane. The magnetization values start increasing systematically with irradiation at lower fluence values, whereas decrease for higher one. This decrease in magnetic signal can be attributed to partial amorphization caused by irradiation in agreement with XRD and atomic/magnetic force microscopic images. Crown Copyright © 2009.517827582761Dash, J., Prasad, S., Venkataramani, N., Kishan, P., Kumar, N., Kulkarani, S.D., Date, S.K., (1999) J. Appl. Phys., 86, p. 3303Acarya, B.R., Krishan, R., Prasad, S., Venkataramani, N., Ajan, A., Shringi, N., (1994) Appl. Phys. Lett., 64, p. 1579Morisako, A., Matsumoto, M., Naoe, M., (1998) IEEE Trans. Magn., 24, p. 3024Hylton, T.L., Parker, M.A., Howard, J.K., (1992) Appl. Phys. Lett., 61, p. 867Sui, X., Kryder, M.H., (1993) Appl. Phys. Lett., 63, p. 1582Cho, H.S., Kim, M.H., Kim, H.J., (1994) J. Mater. Res., 9 (9), p. 2425Venzke, S., van Dover, R.B., Philips, J.M., Gyorgy, E.M., Siegrist, T., Chen, C.H., Werder, D., Opila, R., (1996) J. Mater. Res., 11, p. 1187Kumar, R., Khan, M.W., Srivastava, J.P., Arora, S.K., Sofin, R.G.S., Choudhary, R.J., Shevets, I.V., (2006) J. Appl. Phys., 100, p. 033703Chrisey, D.B., Hubler, G.K., (1994) Pulsed Laser Deposition of Thin Films, , Wiley, New YorkNewman, H.S., Chrisey, D.B., Horwitz, J.S., Weaver, B.D., Reeves, M.E., (1991) IEEE Trans. Magn., 27, p. 2540Cotell, C.M., Chrisey, D.B., Grabowski, K.S., Sprague, J.S., Gossett, C.R., (1992) J. Appl. Biomater., 3, p. 87Neumeier, J.J., Hundley, M.F., Thompson, J.D., Heffner, R.H., (1994) Phys. Rev. B, 52, pp. R7006Ogale, A.S., Shinde, S.R., Kulkarani, V.N., Higgins, J., Choudhary, R.J., Kundaliya, D.C., Pelleto, T., Venkatesan, T., (2004) Phys. Rev. B, 69, p. 235101Ogale, S.B., Ghosh, K., Gu, J.Y., Shreekala, R., Shinde, S.R., Downes, M., Rajeswari, M., Mehta, G.K., (1988) J. Appl. Phys., 84, p. 6255Studer, F., Toulemonde, M., (1992) Nucl. Instrum. Methods B, 65, p. 560Houpert, C., Studer, F., Groult, D., Toulemonde, M., (1989) Nucl. Instrum. Methods B, 39, p. 720Kumar, R., Samantra, S.B., Arora, S.K., Gupta, A., Kanjilal, D., Pinto, R., Narlikar, A.V., (1998) Solid State Commun., 106, p. 805Kumar, R., Arora, S.K., Kanjilal, D., Mehta, G.K., Bache, R., Date, S.K., Shinde, S.R., Patil, S.I., (1999) Radiat. Eff. Defects Solids, 147, p. 187Kumar, S., Alimuddin, Kumar, R., Dogra, A., Reddy, V.R., Banerjee, A., (2006) J. Appl. Phys., 99, pp. 08M910Wang, Z.G., Dufour, Ch., Paumier, E., Toulemonde, M., (1994) J. Phys.: Condens. Matter., 6, p. 6733Kumar, R., Choudhary, R.J., Patil, S.I., Hussain, S., Srivastava, J.P., Sanyal, S.P., Lofland, S.E., (2004) J. Appl. Phys., 96, p. 7383Kumar, R., Singh, F., Angadi, B., Choi, J.W., Choi, W.K., Jeong, K., Song, J.H., Tondon, R.P., (2006) J. Appl. Phys., 100, p. 11370