The Effect of Intensified Insulin Therapy on the Course of Recent Insulin-dependent Diabetes

Dryakova, M .,Koznarova, R .,Bartos, V .,Karasova, L .,Lanska, V .,J . Maly,Ruzickova, J . 대한당뇨병학회 1992 Diabetes and Metabolism Journal Vol.16 No.3

Effect of annealing on the physical properties of thermally evaporated In2S3 thin films

S. Rasool,K. Saritha,K.T. Ramakrishna Reddy,M.S. Tivanov,A.V. Trofimova,S.E. Tikoto,L. Bychto,A. Patryn,M. Maliński,V.F. Gremenok 한국물리학회 2019 Current Applied Physics Vol.19 No.2

The structural, compositional, morphological and optical properties of In2S3 thin films, prepared by thermal evaporation technique and annealed in sulfur ambient at different temperatures have been investigated. The grazing incident X-ray diffraction patterns have indicated polycrystalline form and predominantly cubic structure of annealed In2S3 films. The scanning electron microscopy revealed textured surface with uniformly distributed grains and the grain size increased with increase of annealing temperature. The optical parameters of the films have been determined using conventional transmission and reflection spectra as well as from surface photovoltage measurements.

Low-Cost Electrospun Highly Crystalline Kesterite Cu₂ZnSnS₄ Nanofiber Counter Electrodes for Efficient Dye-Sensitized Solar Cells

Mali, Sawanta S.,Patil, Pramod S.,Hong, Chang Kook American Chemical Society 2014 ACS APPLIED MATERIALS & INTERFACES Vol.6 No.3

<P>In the present investigation, kesterite Cu<SUB>2</SUB>ZnSnS<SUB>4</SUB> (CZTS) nanofibers were obtained by electrospinning process using polyvinylpyrrolidone (PVP) and cellulose acetate (CA) solvent separately. The synthesized CZTS nanofibers were characterized using thermogravimetric analysis (TGA), optical absorption, X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FESEM), micro-Raman spectroscopy, high-resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS). Our results showed that the PVP synthesized CZTS nanofibers are a single crystalline while CA assisted CZTS nanofibers are polycrystalline in nature. The optical properties demonstrated that the prepared nanofibers have strong absorption in 300–550 nm range with band gap energy of 1.5 eV. The X-ray and micro-Raman analysis revealed that synthesised nanofibers showing pure phase kesterite CZTS. Further the synthesized CZTS nanofibers were used as counter electrodes for dye-sensitized solar cells (DSSCs). Our results indicate that, PVP-CZTS and CA-CZTS counter electrode based DSSC shows 3.10% and 3.90% respectively. The detailed interfaces of these counter electrodes and DSSCs were analyzed by electrochemical impedance spectroscopic (EIS) measurements for analysis of such high power conversion efficiency. The present study will be helpful for alternative counter electrode for Pt counter electrodes in DSSCs application. We believe that our synthetic method will be helpful for low-cost and efficient thin film photovoltaic technology.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2014/aamick.2014.6.issue-3/am404586n/production/images/medium/am-2013-04586n_0014.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am404586n'>ACS Electronic Supporting Info</A></P>

Performance predictions and acoustic analysis of the HVAB rotor in hover

Mali, Hajar,Benmansour, Kawtar,Elsayed, Omer,Qaissi, Khaoula Techno-Press 2022 Advances in aircraft and spacecraft science Vol.9 No.4

This work presents a numerical investigation of the aerodynamics and aero acoustics of the HVAB rotor in hover conditions. Two fully turbulent models are employed, the one-equation Spalart-Allmaras model and the two-equation k-ω SST model. Transition effects are investigated as well using the Langtry-Menter γ-Re θt transition transport model. The noise generation and propagation are being investigated using the Ffows-Williams Hawking model for far-field noise and the broadband model for near-field noise. Comparisons with other numerical solvers and with the PSP rotor test data are presented. The results are presented in terms of thrust and power coefficients, the figure of merit, surface pressure distribution, and Sound pressure level. Velocity, pressure, and vortex structures generated by the rotor are also shown in this work. In addition, this work investigates the contribution of different blade regions to the overall noise levels and emphasizes the importance of considering specific areas for future improvements.

Synthesis of SnO₂ nanofibers and nanobelts electron transporting layer for efficient perovskite solar cells

Mali, Sawanta S.,Patil, Jyoti V.,Kim, Hyungjin,Hong, Chang Kook The Royal Society of Chemistry 2018 Nanoscale Vol.10 No.17

<P>The implementation of positive alternative electron transporting layers (ETLs) with excellent electronic properties is a most promising method to up-scale low-cost highly efficient perovskite solar cell (PSC) technology. The present work demonstrates the preparation of tin oxide (SnO2) nanofibers (NF) and nanobelts (NB) as an electron transporting layer (ETL) for PSCs. The smooth and uniform nanofibers and nanobelts have been prepared using an electrospinning technique followed by calcination at 600 °C. Thermogravimetric analysis (TGA) analysis performed on the as-spun polyvinylpyrrolidone-tin oxide (PVP-SnO2) composite suggests that a calcination temperature of 600 °C is required to obtain pure SnO2 and to ensure complete removal of PVP along with other organic solvents. The structural analysis confirmed the presence of the pure tetragonal rutile phase of SnO2 nanofibers and nanobelts. The prepared nanofibers and nanobelts were further used as ETLs for PSCs. Our optimized experimental parameters yielded a <I>J</I>SC of 22.46 mA cm<SUP>−2</SUP>, a <I>V</I>OC of 1.081 V and FF of 66%, leading to >16% power conversion efficiency (PCE) for SnO2 nanobelts using an (FAPbI3)0.85(MAPbI3)0.15 perovskite absorber layer with good stability. The obtained PCE is much higher than that of the SnO2 NF (12.893%) morphology. Nevertheless, the synthesis of SnO2 NF/NB ETLs provides a simple, low-cost and large-scale method for PSCs.</P>

A review on herbal antiasthmatics

Mali, Ravindra G.,Dhake, Avinash S. 경희한의학연구센터 2011 Oriental Pharmacy and Experimental Medicine Vol.11 No.2

In traditional systems of medicine, many plants have been documented to be useful for the treatment of various respiratory disorders including asthma. In the last two decades the use of medicinal plants and natural products has been increased dramatically all over the world. Current synthetic drugs used in pharmacotherapy of asthma are unable to act at all the stages and targets of asthma. However some herbal alternatives employed in asthma are proven to provide symptomatic relief and assist in the inhibition of disease progression also. The herbs have shown interesting results in various target specific biological activities such as bronchodilation, mast cell stabilization, anti-anaphylactic, anti-inflammatory, anti-spasmodic, anti-allergic, immunomodulatory and inhibition of mediators such as leukotrienes, lipoxygenase, cyclooxygenase, platelet activating, phosphodiesterase and cytokine, in the treatment of asthma. This paper is an attempt to classify these pharmacological and clinical findings based on their possible mechanism of action reported. It also signifies the need for development of polyherbal formulations containing various herbs acting at particular sites of the pathophysiological cascade of asthma for prophylaxis as well as for the treatment of asthma.

Synthesis of a nanostructured rutile TiO2 electron transporting layer via an etching process for efficient perovskite solar cells: impact of the structural and crystalline properties of TiO2

Mali, S.,Betty, C. A.,Patil, P. S.,Hong, C. Royal Society of Chemistry 2017 Journal of materials chemistry. A, Materials for e Vol.5 No.24

<P>In the present investigation, hollow and split nanostructures of rutile TiO2 have been synthesized using simple hydrothermal and chemical etching processes. Two typical structures such as TiO2 nanorods and nanoflowers were used as electron transporting layers (ETLs) for perovskite solar cells (PSCs). The optimized nanostructured ETLs were then used for mixed halide PSCs such as methyl ammonium iodide (MAPbI(3)), methyl ammonium iodide/chloride mixed-halide perovskite (MAPbI(3-x)Cl(x)) and (FAPbI(3))(0.85)(MAPbBr(3))(0.15) (herein FAPbI(3) = formamidinium lead halide and MAPbBr(3) = methylammonium lead bromide). The optimized results show a eta = 15.87% efficiency (J(SC) = 20.75 mA cm(-2), V-OC = 1.034, FF = 0.74) and a eta = 17.55% efficiency (J(SC) = 21.72 mA cm(-2), V-OC = 1.073, FF = 0.76) for (MAPbI(3-x)Cl(x)) and (FAPbI(3))(0.85)(MAPbBr(3))(0.15), respectively, for etched TiO2 with a split structure.</P>

Efficient planar n-i-p type heterojunction flexible perovskite solar cells with sputtered TiO2electron transporting layers

Mali, Sawanta S.,Hong, Chang Kook,Inamdar, A. I.,Im, Hyunsik,Shim, Sang Eun The Royal Society of Chemistry 2017 Nanoscale Vol.9 No.9

<P>The development of hybrid organo-lead trihalide perovskite solar cells (PSCs) comprising an electron transporting layer (ETL), a perovskite light absorber and a hole transporting layer (HTL) has received significant attention for their potential in efficient PSCs. However, the preparation of a compact and uniform ETL and the formation of a uniform light absorber layer suffer from a high temperature processing treatment and the formation of unwanted perovskite islands, respectively. A low temperature/room temperature processed ETL is one of the best options for the fabrication of flexible PSCs. In the present work, we report the implementation of a room temperature processed compact TiO2 ETL and the synthesis of extremely uniform flexible planar PSCs based on methylammonium lead mixed halides MAPb (I-1-(X) Br-x)(3) (x = 0.1) via RF-magnetron sputtering and a toluene dripping treatment, respectively. The compact TiO2 ETLs with different thicknesses (30 to 100 nm) were directly deposited on a flexible PET coated ITO substrate by varying the RF-sputtering time and used for the fabrication of flexible PSCs. The photovoltaic properties revealed that flexible PSC performance is strongly dependent on the TiO2 ETL thickness. The open circuit voltage (V-OC) and fill factor (FF) are directly proportional to the TiO2 ETL thickness while the 50 nm thick TiO2 ETL shows the highest current density (J(SC)) of 20.77 mA cm(-2). Our controlled results reveal that the room temperature RF-magnetron sputtered 50 nm-thick TiO2 ETL photoelectrode exhibits a power conversion efficiency (PCE) in excess of 15%. The use of room temperature synthesis of the compact TiO2 ETL by RF magnetron sputtering results in an enhancement of the device performance for cells prepared on flexible substrates. The champion flexible planar PSC based on this architecture exhibited a promising power conversion efficiency as high as 15.88%, featuring a high FF of 0.69 and V-OC of 1.108 V with a negligible hysteresis under AM 1.5 G illumination. Furthermore, the mechanical bending stability revealed that the fabricated devices show stable PCE up to 200 bending cycles. The interface properties revealed that the 50 nm thick TiO2 ETL provides superior charge injection characteristics and low internal resistance. The present work provides a simplistic and reliable approach for the fabrication of highly efficient stable flexible perovskite solar cells.</P>

Reduced graphene oxide (rGO) grafted zinc stannate (Zn2SnO4) nanofiber scaffolds for highly efficient mixed-halide perovskite solar cells

Mali, Sawanta S.,Shim, Chang Su,Kim, Hyungjin,Hong, Chang Kook The Royal Society of Chemistry 2016 Journal of materials chemistry. A, Materials for e Vol.4 No.31

<P>Electron transporting materials based on ternary metal oxides (TMOs) are the best electron transport layers (ETLs) for perovskite solar cells (PSCs). In the present investigation, reduced graphene oxide (rGO) grafted highly porous zinc stannate (Zn2SnO4) (ZSO) nanofiber scaffolds have been synthesized by a single step electrospinning technique and successfully used as ETLs for mixed halide PSCs whose perovskite material is composed of MAPb(I1−xBrx)3and (FAPbI3)0.85(MAPbBr3)0.15(MA: methyl ammonium and FA: formamidinium). The fabricated optimized perovskite solar cells having FTO/Bl-ZSO/rGO-ZSO0.7-MAPb(I1−xBrx)3/PTAA/Au devices exhibited a 13.41% power conversion efficiency (PCE) with an open circuit voltage (<I>V</I>OC) of 1.036 V, a current density (<I>J</I>SC) of 19.62 mA cm<SUP>−2</SUP>and a fill factor (FF) of 0.66 under AM 1.5G sunlight (100 mW cm<SUP>−2</SUP>) which is higher than that of bare Zn2SnO4nanofiber (<I>η</I>= 7.38%) based PSCs. The optimized conditions were further used for formamidinium lead halide (FAPbI3)1−x(MAPbBr3)x(<I>x</I>= 0.15) perovskite and our optimized results show<I>η</I>= 17.89% PCE (<I>J</I>SC= 22.50 mA cm<SUP>−2</SUP>,<I>V</I>OC= 1.046 V, FF = 0.76) for the FTO/Bl-ZSO/rGO-ZSO0.7-(FAPbI3)0.85(MAPbBr3)0.15/PTAA/Au device configuration. The role of rGO grafting and electron transfer mechanisms are investigated with complementary characterization, including photoluminescence (PL) and time-resolved photoluminescence (TRPL) decay measurements. The TRPL results revealed that the grafting of rGO in ZSO scaffolds reduces the slow decay lifetime which facilitates efficient electron injection from the perovskite conduction band (CB) to the rGO Fermi level to the CB of ZSO compared to the bare ZSO ETL. Furthermore, the stability of these devices based on various configurations has been discussed. This improvement is achieved due to the high conductivity of rGO and grafting with high porosity Zn2SnO4nanofibers which make them promising new ETLs for the fabrication of highly efficient PSCs.</P>

Simultaneous recovery of valuable metals from spent mobile phone battery by an acid leaching process

Mali Hunsom,Supasan Sakultung,Kejvalee Pruksathorn 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.2

research was carried out to recover some valuable metals from the electrodes of spent mobile phonenickel-metal hydride (Ni-MH) and lithium-ion (Li-ion) batteries. Effects of parameters including types of acid (H2SO4,HNO3 and HCl), acid concentration (1-6 M), solid-liquid ratio (10-40 g/l), leaching time (5-120 min) and leaching tem-perature (303-363 K) on the leaching percentages of Co and Ni were investigated. The preliminary results indicatedthat HCl provided higher leaching percentages than that of H2SO4 and HNO3 for both metals at all leaching conditions.At optimum conditions, greater than 92% and 84% of Ni and Co were leached, respectively. Further investigation in-dicated that the leaching process of both metals was endothermic with the rate law of a second-order reaction and itskinetics was principally controlled by the physical proces.