Influence of growth temperature and post-annealing on an n-ZnO/p-GaN heterojunction diode

Sharma, S.K.,Heo, S.,Lee, B.,Lee, H.,Kim, C.,Kim, D.Y. Elsevier 2014 CURRENT APPLIED PHYSICS Vol.14 No.12

We report on an n-ZnO/p-GaN heterojunction diode fabricated from zinc oxide (ZnO) films at various growth temperatures (450, 500, 550, and 600 <SUP>o</SUP>C) by RF sputtering. The films were subsequently annealed at 700 <SUP>o</SUP>C in N<SUB>2</SUB> ambient. To investigate the influence of the growth temperature of n-ZnO films, the microstructural, optical, and electrical properties were measured using scanning electron microscopy (SEM), X-ray diffraction (XRD), photoluminescence (PL), and Hall measurements. The XRD pattern showed the preferred orientation along the c-axis (002) regardless of growth temperature. The PL spectra showed a dominant sharp near-band-edge (NBE) emission. Current-voltage (I-V) curves showed excellent rectification behavior. The turn-on voltage of the diode was observed to be 3.2 V for the films produced at 500 <SUP>o</SUP>C. The ideality factor of ZnO film was observed to be 1.37, which showed the best performance of the diode.

Characterization of dihydrolipoamide dehydrogenase from the mitochondria of Helicoverpa armigera, a pest resistant to insecticides

S. Md. AKBAR,S. K. JAYALAKSHMI,H. C. SHARMA,K. SREERAMULU 한국곤충학회 2011 Entomological Research Vol.41 No.6

Dihydrolipoamide dehydrogenase (DHLDH) was isolated from the mitochondria of Helicoverpa armigera, a destructive pest which has developed resistance to commonly used insecticides. The flavoenzyme was purified 17.98-fold to homogeneity with an overall yield of 10.53% by employing ammonium sulfate precipitation, hydroxylapatite chromatography and CM-Sephadex chromatography. The purified enzyme exhibited the specific activity of 18.7 U/mg and was characterized as a dimer with a subunit mass of 66 kDa. The enzyme showed specificity for nicotinamide adenine dinucleotide – hydrogen (NADH) and lipoamide, as substrates, with Michaelis-Menten constants (K_m) of 0.083 mmol/L and 0.4 mmol/L, respectively. The reduction reaction of lipoamide by the enzyme could be explained by ping-pong mechanism. The spectra of DHLDH showed the maximum absorbance at 420 nm, 455 nm and 475 nm. The enzyme activity was strongly inhibited by mercurial and arsenical compounds. The N-terminal sequence of Ha-DHLDH showed homology with those of mammalian and arthropod DHLDH. Since H. armigera has developed high levels of resistance to commonly used insecticides, biochemical properties of the metabolic enzymes such as DHLDH, could be helpful to develop insecticidal molecules for the control of H. armigera, with a different mode of action.

Reduced graphene oxide modified smart conducting paper for cancer biosensor

Kumar, Saurabh,Kumar, Suveen,Srivastava, Saurabh,Yadav, Birendra K.,Lee, Seung H.,Sharma, Jai G.,Doval, Dinesh C.,Malhotra, Bansi D. Elsevier 2015 Biosensors & bioelectronics Vol.73 No.-

<P><B>Abstract</B></P> <P>We report results of the studies relating to the fabrication of a paper based sensor comprising of poly (3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and reduced graphene oxide (RGO) composite. The effect of various solvents like methanol, ethylene glycol and H<SUB>2</SUB>SO<SUB>4</SUB> on the electrical conductivity of PEDOT:PSS coated Whatman paper has been investigated. The conductivity of this solution processed conducting paper significantly increases from ~1.16×10<SUP>−4</SUP> Scm<SUP>−1</SUP> up to ~3.57×10<SUP>−2</SUP> Scm<SUP>−1</SUP> (~300 times) on treatment with ethylene glycol. The observed significant increase in electrical conductivity is due to conformational rearrangement in the polymer and is due to strong non-covalent cooperative interaction between PEDOT and the cellulose molecules. Further, incorporation of RGO into the conducting paper results in improved electrochemical performance and signal stability. This paper electrode is a promising alternative over the expensive conventional electrodes (ITO, gold and glassy carbon), that are known to have limited application in smart point-of-care (POC) devices. This low cost, flexible and environment friendly conducting paper based biosensor utilized for cancer biomarker (carcinoembryonic antigen, CEA) detection reveals high sensitivity of 25.8µAng<SUP>−1</SUP> mLcm<SUP>−2</SUP> in the physiological range, 1–10ngmL<SUP>−1</SUP>.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Solution processed reduced graphene oxide modified conducting paper sensor is reported for cancer detection. </LI> <LI> This paper sensor is exceptionally low cost, flexible and disposable. </LI> <LI> It exhibits high sensitivity of 25.8µAng<SUP>−1</SUP> mLcm<SUP>−2</SUP> in the detection range of 1–10ngmL<SUP>−1</SUP> for cancer biomarker (carcinoembryonic antigen, CEA) detection. </LI> <LI> This conducting paper electrode is a promising alternative over the expensive conventional electrodes (ITO, gold and glassy carbon) for application to POC devices. </LI> </UL> </P>

Studies on Serum Micro-mineral, Hormone and Vitamin Profile and Its Effect on Production and Therapeutic Management of Buffaloes in Haryana State of India

Sharma, M.C.,Raju, S.,Joshi, C.,Kaur, H.,Varshney, V.P. Asian Australasian Association of Animal Productio 2003 Animal Bioscience Vol.16 No.4

A survey was conducted in certain parts of Haryana to record the prevalence of micro mineral deficiency in buffaloes. The prevalence of soil Cu, Co, Zn and Fe deficiency was 55.26%, 6.9%, 59.12% and 7.89% respectively. While that of fodder Cu, Co, Zn and Fe was 60.64%, 6.7%, 61.22% and 11.37% respectively. The overall prevalence of serum Cu, Co, Zn and Fe deficiency in Haryana was 59.2%, 19.1%, 59.2% and 19.9% respectively. The correlation co-efficient of Cu, Co, Zn and Fe in soil, fodder and serum was significant in most of the cases the values were above 0.8. Blood examination revealed significant decrease in haemoglobin and TEC level. However, no variation in level of TLC were observed in mineral deficient buffaloes. In micro mineral deficiency, thyroid hormone (T3 and T4) levels were decreased in buffaloes. Marginally lower concentration of vitamin A and E were observed in mineral deficient buffaloes in Haryana. The highest deficiency of micro minerals was 61.76% in copper at Ambala followed by 65.86% in zinc at Rhotak. For therapeutic studies a mineral mixture was prepared according to defiency obtained and fed to three groups of animals. Observation was recorded on 0, 15, 30, 45 and 60 days. Group A consist of normal healthy animals and group B mineral deficient animal untreated and group C mineral deficient animal, treated with prepared mineral mixture. 25 gram of mineral mixture was fed daily along with normal ration. There was increase in body weight, milk yield, haemoglobin concentration and total erythrocyte level in group C animals when compared to group B animals. The milk yield in group C animals increased to 6.970${\pm}$0.41 after 60th day of supplement in comparison to 0 day where it was 5.910${\pm}$0.37, similarly the body wt. of group C animals increased from 129.42${\pm}$01.13 (at 0 day) to 159.31${\pm}$03.61 at 60th day of treatment.

Photo-physics of PTB7, PCBM and ICBA based ternary solar cells

Sharma, R.,Lee, H.,Gupta, V.,Kim, H.,Kumar, M.,Sharma, C.,Chand, S.,Yoo, S.,Gupta, D. Elsevier Science 2016 Organic Electronics Vol.34 No.-

<P>Indene-C(60)bisadduct (ICBA) is one of the rare acceptors which can supersede commonly used phenyl-C71-butyric acid methyl ester (PCBM70) in enhancing the performance of bulk heterojunction (BHJ) solar cells owing to its shallower lowest unoccupied molecular orbital (LUMO) level. However, ICBA tends to decrease the photocurrent for most of the low band-gap polymers synthesized to date. Here we examine the interaction of ICBA with the one of the popular low band-gap polymers poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thio-phenediyl]] (PTB7), at femtosecond level, to explore key dynamics governing the operation of BHJ cells involving ICBA. The photo-physics of binary and ternary systems based on PTB7 coupled with PCBM70 and/or ICBA are studied by means of transient absorption spectroscopy (TAS) and electrochemical impedance spectroscopy (EIS) and supported by morphology analysis. Our study suggests that both inefficient charge-separation and poor charge transport of ICBA is responsible for relatively low photocurrent generation. (C) 2016 Elsevier B.V. All rights reserved.</P>

Genome-wide Association Study for Warner-Bratzler Shear Force and Sensory Traits in Hanwoo (Korean Cattle)

Dang, C.G.,Cho, S.H.,Sharma, A.,Kim, H.C.,Jeon, G.J.,Yeon, S.H.,Hong, S.K.,Park, B.Y.,Kang, H.S.,Lee, S.H. Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.9

Significant SNPs associated with Warner-Bratzler (WB) shear force and sensory traits were confirmed for Hanwoo beef (Korean cattle). A Bonferroni-corrected genome-wide significant association (p< $1.3{\times}10^{-6}$) was detected with only one single nucleotide polymorphism (SNP) on chromosome 5 for WB shear force. A slightly higher number of SNPs was significantly (p<0.001) associated with WB shear force than with other sensory traits. Further, 50, 25, 29, and 34 SNPs were significantly associated with WB shear force, tenderness, juiciness, and flavor likeness, respectively. The SNPs between p = 0.001 and p = 0.0001 thresholds explained 3% to 9% of the phenotypic variance, while the most significant SNPs accounted for 7% to 12% of the phenotypic variance. In conclusion, because WB shear force and sensory evaluation were moderately affected by a few loci and minimally affected by other loci, further studies are required by using a large sample size and high marker density.

Influence of pulsed electric field and heat treatment on Emblica officinalis juice inoculated with Zygosaccharomyces bailii

Bansal, V.,Sharma, A.,Ghanshyam, C.,Singla, M.L.,Kim, K.H. The Institution ; Hemisphere Pub. Corp. [distribut 2015 Food and bioproducts processing Vol.95 No.-

The effects of pulsed electric field (PEF) applying 26kVcm<SUP>-1</SUP> with 1μs monopolar pulses (for 500μs) on inactivation of Zygosaccharomyces bailii and the stability for the key quality characteristics (vitamin C, phenolic content, antioxidant capacity, nonenzymatic index, 5-hydroxymethyl-2-furfural (HMF), <SUP>o</SUP>brix, and pH) in Emblica officinalis juice were studied. These results were then compared to those of heat treatment (90<SUP>o</SUP>C for 60s) up to 40 days on storing at 4<SUP>o</SUP>C. PEF treatment reduced 5.1log cycles of Z. bailii with decreases in HMF concentration and browning index relative to heat treated juice. Simultaneously, PEF treated juice retained 63% of vitamin C and 88.9% of antioxidant capacity (p<0.05). However, heat treated juice lowered 4.9log cycles of Z. bailii and exhibited significant degradation of vitamin C and antioxidant capacity (p<0.01). After all, both treatments did not induce any major changes in pH and <SUP>o</SUP>brix levels of emblica juice. Electron microscopy was used as a tool to find Z. bailii damage induced. Investigation of their morphology showed a leakage of cellular debris owing to the rupture of cell membrane of PEF treated Z. bailii. Thus, PEF treatment on emblica juice may offer an enormous potential for upgrading its quality than the heat processing method.

A novel orange-red emitting Ba2Ca(BO3)2:Sm3+ phosphor to fill the amber gap in LEDs: Synthesis, structural and luminescence characterizations

M. Manhas,Vinay Kumar,Vivek K. Singh,J. Sharma,Ram Prakash,Vishal Sharma,A.K. Bedyal,H.C. Swart 한국물리학회 2017 Current Applied Physics Vol.17 No.11

The present paper reports on the structural and luminescent properties of un-doped and Sm3þ doped Ba2Ca(BO3)2 phosphors synthesized by the conventional solid state method. For structural characterizations, the X-ray diffraction, FTIR spectroscopy and Rietveld refinement method were used. The FTIR spectrum was composed of basic BO3 and BO4 structural units of borates. The Sm3þ doped phosphors under 402 nm (6H5/2/4L13/2) excitation, showed an orange red emission corresponding to the 601 nm (4G5/2 / 6H7/2) transition of the Sm3þ ion. An increase in the PL emission intensity was observed up to 2 mol % with the increase in Sm3þ ions concentration. The critical distance between the Sm3þ e Sm3þ ions were found to be 24.36 Å. Moreover, the phosphors decaytime and optical bandgap at different concentration of Sm3þ ion also have been discussed in details. All the results show that Ba2Ca(BO3)2:Sm3þ phosphor may be used with a near ultraviolet (n-UV) chip to fill the amber gap in light emitting diodes (LEDs).

Optimizing the electromechanical response in morphotropic BiFeO₃

Sharma, P,Kang, K-R,Liu, Y-Y,Jang, B-K,Li, J-Y,Yang, C-H,Seidel, J IOP 2018 Nanotechnology Vol.29 No.20

Glycyrrhetinic acid as a hepatocyte targeting unit for an anticancer drug delivery system with enhanced cell type selectivity

Singh, H.,Kim, S.,Kang, D.,Kim, H. R.,Sharma, A.,Kim, W.,Kang, C.,Kim, J. Royal Society of Chemistry 2018 Chemical communications Vol.54 No.87