Showing papers by "Kuvempu University published in 2008"
TL;DR: In this paper, the corrosion inhibition effect of 4-{[(1Z)-(2-chloroquinolin-3-yl)methylene]amino} phenol (CAP), N -[1Z]-( 2-chlorosinoline-methylene]- N -(4-methoxyphenyl)amine (CMPA) and N-[1E]-(2 -chloroencinnol-3yl) methylene]-N -nitrophenylamine (CNPA) compounds on mild steel in 1.0
231 citations
TL;DR: A novel series of 4-pyrrol-1-yl benzoic acid hydrazide analogs have been synthesized in good yields and characterized by IR, NMR, mass spectral and elemental analyses and some compounds showed very good antibacterial and antitubercular activities.
204 citations
TL;DR: In this paper, nanosized TiO 2 particles were prepared by sol-gel method and co-deposited with zinc from a sulphate bath at pH 4.5 using electrodeposition technique.
162 citations
TL;DR: MMCD is a practical tool for expediting the time-consuming steps of identifying and researching small molecules and is compatible with both NMR and MS data and facilitates high-throughput metabolomics investigations.
Abstract: Proteomic technologies, such as yeast two-hybrid, mass spectrometry (MS), protein/peptide arrays and fluorescence microscopy, yield multi-dimensional data sets, which are often quite large and either not published or published as supplementary information that is not easily searchable. Without a system in place for standardizing and sharing data, it is not fruitful for the biomedical community to contribute these types of data to centralized repositories.
157 citations
TL;DR: A triterpene compound lupeol isolated from petroleum ether extract of leaves of Celastrus paniculatus was screened for wound healing activity by excision, incision and dead space wound models on Swiss Albino rats and supported the wound healing property.
99 citations
TL;DR: In this article, the authors investigated the inhibition effects of 8-hydroxy quinoline (HQ) and 3-formyl 8-hexoxyquinoline(FQ) on corrosion of mild steel in hydrochloric acid and found that FQ showed more corrosion inhibition efficiency than HQ.
99 citations
TL;DR: In this article, the single-phase spinel formation of polycrystalline soft ferrites was confirmed by X-ray diffraction technique and the dielectric measurements were carried out at room temperature as a function of frequency and composition.
97 citations
TL;DR: In this paper, the authors investigated the corrosion inhibition effect of 3-[(E)-(phenylimino)methyl]quinoline-2-thione (PMQT), 3{(E]-[(4-chlorophenyl)imino]methyl}quinoline 2 thione (CPMQTs), and 3{ (E)-[ (4-fluorophenyl)-imino]-methyl} quinoline 2thione(FPMQTs) on mild steel in 1.5 µm −3 HCl at 300 K.
79 citations
TL;DR: Significantly more isolates were obtained during the winter season than monsoon and summer seasons and Alternaria, Chaetomium, Fusarium, Colletotrichum, Cladosporium, Penicillium, Phyllosticta and Xylaria were the most frequently isolated.
78 citations
TL;DR: In this article, the miscibility of HPMC/PEG blends in water was studied by viscosity, ultrasonic velocity, density and refractive index techniques at 30 and 50 °C.
54 citations
TL;DR: The photocleavage studies with pUC19 DNA shows that all these complexes promoted the conversion of SC form to NC form in absence of ‘inhibitors’.
Abstract: In order to systematically perform an experimental and theoretical study on DNA binding and photocleavage properties of transition metal complexes of the type [M(L)2(L1)](PF6)n · xH2O (where M = Co(III) or Ni(II), L = 1,10-phenanthroline or 2.2′ bipryidine, L1 = Thiophene [2,3-b] quinoline (qt), n = 3 or 2 and x = 5 or 2) have been synthesized and characterized by elemental analysis, IR, 1H NMR, UV and magnetic susceptibility data. The DNA-binding properties of these complexes have been investigated with UV-Vis, viscosity measurements, thermal denaturation and cyclic voltametric studies. It is experimentally found that all the complexes are bound to DNA via intercalation in the order [Co(bpy)2(qt)](PF6)3 > [Co(phen)2(qt)](PF6)3 > [Ni(phen)2(qt)](PF6)2 > [Ni(bpy)2(qt)](PF6)2. The photocleavage studies with pUC19 DNA shows that all these complexes promoted the conversion of SC form to NC form in absence of ‘inhibitors’.
TL;DR: The structures of the newly synthesized compounds have been established on the basis of their spectral data and elemental analysis and some selected compounds were evaluated for antiinflammatory, analgesic, CNS depressant and skeletal muscle relaxant activity.
Abstract: Various 7-chloro-6-fluoro-2-arylidenylaminobenzo(1,3)thiazole (2a-h) have been synthesized by the condensation of 7-chloro-6-fluoro-2-aminobenzo(1,3)thiazole (1) with different aromatic aldehydes. The Schiff's bases on reaction with acetyl chloride, chloroacetyl chloride and phenyl acetyl chloride yielded 1-(7-chloro-6-fluorobenzothiazol-2-yl)-3,4-substituted-aryl-azetidin-2-ones (3a-x). Similarly, cyclization of Schiff's base with thioglycolic acid furnished 3-(7-chloro-6-fluoro-benzothiazol-2-yl)-2-substituted-arylthiazolidin-4-ones (4a-h). The structures of the newly synthesized compounds have been established on the basis of their spectral data and elemental analysis. Some selected compounds were evaluated for antiinflammatory, analgesic, CNS depressant and skeletal muscle relaxant activity.
TL;DR: Alcohol extract showed significant reactive oxygen species (ROS) scavenging activity in all in vitro antioxidant assays and contained high level of total phenolic content and moderate cytotoxicity against L929 cell line.
TL;DR: In this article, Hevea brassiliensis (rubber wood) was esterified with palmitoyl chloride, prepared from the reaction of palmitic acid with thionyl chloride.
TL;DR: In this article, the corrosion inhibition characteristics of N′-[(1E)-(4-hydroxy phenyl) methylene] isonicotinohydrazide (HIH) and N′[1E]-(4,hydroxyl-3-methoxy phenyl)-methylene]-isonic-methylene [HMIH on mild steel corrosion in 1M hydrochloric acid were investigated by weight loss, potentiodynamic polarization and impedance techniques.
Abstract: The corrosion inhibition characteristics of N′-[(1E)-(4-hydroxy phenyl) methylene] isonicotinohydrazide (HIH) & N′-[(1E)-(4-hydroxyl-3-methoxy phenyl) methylene] isonicotinohydrazide (HMIH) on mild steel corrosion in 1 M hydrochloric acid were investigated by weight loss, potentiodynamic polarization and impedance techniques. The inhibition efficiency increased with increase in inhibitor concentration but decreased with increase in temperature. The thermodynamic functions of dissolution and adsorption processes were evaluated. The polarization measurements indicated that the inhibitors are of mixed type. The adsorption of the compounds was found to obey Langmuir’s adsorption isotherm. Passive film characterization was done by Fourier transform infrared (FTIR) spectra and scanning electron microscopy (SEM).
TL;DR: Fungal communities were isolated from surface sterilized leaf segments of nine ethnopharmaceutically important medicinal herbs collected from the Bhadra River Project Area, the Malnad region, Southern India, and Colonization rates of fungal species varied significantly between the two seasons.
Abstract: Fungal communities were isolated from surface sterilized leaf segments of nine ethnopharmaceutically important medicinal herbs collected from the Bhadra River Project Area, the Malnad region, Southern India. A total of 2159 isolates belonging to 55 different fungal species were isolated from 3600 leaf segments collected during the wet and dry seasons. Chaetomium globosum (7.3%), Aureobasidium pullulans (6.1%), Cladosporium cladosporioides (3.9%), Curvularia lunata (1.9%), Nigrospora oryzae (1.7%), Alternaria alternata (1.3%), Botryosphaeria subglobosa (1.1%), Phoma multirostrata (0.9%), Aspergillus niger (0.8%), Fusarium oxysporum (0.7%), Rhizoctonia solani (0.4%), and Sphaeropsis sapenea (0.3%) were the most frequently isolated fungal species. Colonization rates of fungal species varied significantly between the two seasons. Host specificity was observed in some host plants.
TL;DR: In this paper, the corrosion behavior of mild steel in sulphuric acid solution containing various concentrations of a co-polymer formed between maleic anhydride and N -vinyl-2-pyrrolidone (VPMA) was investigated using weight-loss, polarization and electrochemical impedance techniques.
Journal Article•
TL;DR: Freshwater fish Cirrhinus mrigala were exposed to lethal concentration and sublethal concentration for 1,7,14,21 days of cypermethrin to examine the enzymes activity, in functionally three different tissues namely, gill, liver and muscle, with increase in exposure time.
Abstract: Freshwater fish Cirrhinus mrigala were exposed to lethal concentration (5 μg/L) for 1,2,3,4 days and sublethal concentration (1 μg/L) for 1,7,14,21 days of cypermethrin to examine the enzymes activity, in functionally three different tissues namely, gill, liver and muscle. Activities of Aspartate aminotransferase (AAT), Alanine aminotransferase (AlAT) and Glutamate dehydrogenase (GDH) increased in all the tissues with increase in exposure time. But in sublethal concentration at 14 and 21 day, a decreasing trend was observed in all the tissues exposed to cypermethrin. At most instances, fish in lethal medium were affected more compared to sublethal concentration.
TL;DR: In this paper, the surface treatment of zinc and its corrosion inhibition using a product (BTSC) formed in the reaction between benzaldehyde and thiosemicarbozide was studied using a galvanostatic polarization technique.
Abstract: The surface treatment of zinc and its corrosion inhibition was studied using a product (BTSC) formed in the reaction between benzaldehyde and thiosemicarbozide. The corrosion behaviour of chemically treated zinc surface was investigated in aqueous chloride-sulphate medium using galvanostatic polarization technique. Zinc samples treated in BTSC solution exhibited good corrosion resistance. The measured electrochemical data indicated a basic modification of the cathode reaction during corrosion of treated zinc. The corrosion protection may be explained on the basis of adsorption and formation of BTSC film on zinc surface. The film was binding strongly to the metal surface through nitrogen and sulphur atoms of the product. The formation of film on the zinc surface was established by surface analysis techniques such as scanning electron microscopy (SEM-EDS) and Fourier transform infrared spectroscopy (FTIR).
TL;DR: In this article, nanocrystalline zinc coatings were deposited from acid zincate bath containing newly synthesized condensation product, and the effect of bath constituents, pH, temperature and current density on the deposit nature were investigated through Hull cell experiments.
Abstract: Nanocrystalline zinc coatings were deposited from acid zincate bath containing newly synthesized condensation product. The effect of bath constituents, pH, temperature and current density on the deposit nature were investigated through Hull cell experiments. Current efficiency, throwing power, cathodic polarization and corrosion behavior in 3.5 wt.% NaCl were studied under optimum concentration of additives. Salt spray test and electrochemical measurements showed that nanocrystalline zinc coatings have better corrosion resistance than the zinc coatings deposited from a simple acid zincate bath without additive. The surface morphology and thickness (cross section) of the zinc deposits were studied by scanning electron microscopy (SEM). The preferred orientation and average grain size of the zinc electrodeposit were obtained by X-ray diffraction analysis. The particle size was also characterized by TEM analysis. Energy X-ray diffraction (EDX) and FT-IR spectral analysis were carried out to determine the inclusion of addition agent in the deposit. The experimental results indicated that the addition of condensation product of thiamine hydrochloride (THC) and furfural (FFL) leads to a more uniform nanocrystalline deposition with the grain sizes varying from 20–22 nm.
TL;DR: A simple protocol was established to synthesize 2,3-dialkyl indoles and various tetrahydrocarbazoles via Fischer indole synthesis as mentioned in this paper, which uses ceric ammonium nitrate as a catalyst for the Fischer Indole synthesis with substituted phenyl hydrazine hydrochlorides and 2-butanone, phenyl propanal, and cyclohexanone.
TL;DR: In this article, the influence of polyaniline functionalized multiwalled carbon nanotubes (PANI-MWNTs) on the positive temperature coefficient (PTC) characteristics of carbon black (CB) filled high-density polyethylene (HDPE) nanocomposite materials have been studied.
Abstract: The influence of addition of polyaniline functionalized multiwalled carbon nanotubes (PANI-MWNTs) on the positive temperature coefficient (PTC) characteristics of carbon black (CB) filled high-density polyethylene (HDPE) nanocomposite materials have been studied. Polymer nanocomposites were prepared by the combined solution and melt-mixing process. The experimental results showed that the PTC intensity and maximum resistivity of the hybrid nanocomposites were obviously influenced by the polyaniline functionalization of multiwalled carbon nanotubes (MWNTs). A noticeable PTC of resistivity was observed for PANI-MWNTs/CB/HDPE hybrid nanocomposites near the melting point of HDPE. This is due to the significant volume expansion near the melting point of the HDPE in presence of hybrid fillers and a sudden increase of the resistivity due to the disconnection of the conductive paths. The PTC effect of CB/HDPE composites can be effectively modified by the addition of PANI-MWNTs.
TL;DR: In this article, 4.4-Nitrophthalic acid was found to be an effective catalyst for the imino Diels-Alder reaction of N-benzylideneanilines with 3,4-dihydro-2H-pyran and 2,3-dishydrofuran to afford pyrano-and furanoquinolines in good yields.
Abstract: 4-Nitrophthalic acid was found to be an effective catalyst for the imino Diels-Alder reaction of N-benzylideneanilines with 3,4-dihydro-2H-pyran and 2,3-dihydrofuran to afford pyrano- and furanoquinolines in good yields. It was also found that aryl amines react smoothly with 3,4-dihydro-2H-pyran and 2,3-dihydrofuran under the same condition to afford the corresponding pyrano- and furanoquinolines in high yields. This catalyst is inexpensive, easily available, water soluble, and stable to aqueous reaction conditions.
TL;DR: These natural products may be alternatives to chemical fungicides and provide an easy method to protect soybean and other agricultural commodities from A. flavus in storage.
TL;DR: Aryl amines react smoothly and efficiently with N-vinyl pyrrolidin-2-one in the presence of 4-nitro phthalic acid in acetonitrile to afford the corresponding 1-(2-methyl-1,2,3,4,4-tetrahydroquinolin-4-yl)pyrrolidsin-1.
TL;DR: Antimony sulfate was found to be an effective catalyst for the condensation reaction of indoles with carbonyl compounds at room temperature as mentioned in this paper, and it was also found that this catalyst could be recovered quantitatively and reused without much loss of catalytic activity.
Abstract: Antimony sulfate was found to be on effective catalyst for the condensation reaction of indoles with carbonyl compounds at room temperature. This catalyst is inexpensive, easily available and it was also found that this catalyst could be recovered quantitatively and reused without much loss of catalytic activity.
TL;DR: A mild and efficient condensation reaction of indoles with various aldehydes and ketones under catalysis of antimony trichloride (SbCl3) afforded biologically important bis(indolyl)methanes in good yield as mentioned in this paper.
Abstract: A mild and efficient condensation reaction of indoles with various aldehydes and ketones under catalysis of antimony trichloride (SbCl3) afforded biologically important bis(indolyl)methanes in good yield The structures of all the newly synthesized compounds were elucidated on the basis of IR, 1H NMR and mass spectral data
TL;DR: In this article, the effect of additive on the morphology of crystal size on zinc deposit surface and corrosion properties was investigated, and the results showed that addition of additive in the deposition process of zinc significantly increased the corrosion resistance.
Abstract: Nano zinc coatings were deposited on mild steel by electrodeposition. The effect of additive on the morphology of crystal size on zinc deposit surface and corrosion properties were investigated. Corrosion tests were performed for dull zinc deposits and bright zinc deposits in aqueous NaCl solution (3·5 wt.%) using electrochemical measurements. The results showed that addition of additive in the deposition process of zinc significantly increased the corrosion resistance. The surface morphology of the zinc deposits was studied by scanning electron microscopy (SEM). The preferred orientation and average size of the zinc electrodeposited particles were obtained by X-ray diffraction analysis. The particles size was also characterized by TEM analysis.
TL;DR: Results demonstrated that the percentage of changes of FBS at the dose of 100 mg/kg.
Abstract: In the present study, the ethanolic extract and a purifi ed fraction-1of stem of Bauhinia purpurea Linn. (BP) were investigated for anti-diabetic activity and adrenergic property. Th e anti-diabetic activity of the extract and fraction-1 was compared with standard insulin and adrenergic property was compared with sympathetic agonists and its blocker. Th e results demonstrated that the percentage of changes of FBS at the dose of 100 mg/kg. (i.p.) of ethanolic extract of BP and fraction-1 were statistically signifi cant (p < 0.001). Th e same fraction exhibited excellent adrenergic activity (10 mg/ml). Th is was further confi rmed as its action was blocked by an adrenergic β2-blocker (propranolol). Key words: Adrenaline, anti-diabetic activity, alloxan, Bauhinia purpurea Linn., insulin, propranolol
TL;DR: In this article, the DNA binding properties of mixed ligand complexes with calf thymus-DNA were studied by using absorption spectra, viscosity measurements as well as thermal denaturation experiments.
Abstract: Mixed ligand complexes of the type [Ni(phen)2(bnp)](PF6)2 · 2H2O (1) and [Ni(bpy)2(bnp)](PF6)2 · 2H2O (2) (where phen, 1,10,Phenanathroline; bpy, 2,2 bipyridine; bnp, benzo[1.8]naphthyridinone-2-ol) have been synthesized and characterized by employing analytical and spectral methods. The DNA binding properties of the complexes with calf thymus-DNA were studied by using absorption spectra, viscosity measurements as well as thermal denaturation experiments. The absorption spectra indicated that the Ni(II) complexes intercalate tightly between the base pairs of the DNA with intrinsic DNA binding constants of 1.9 × 104 M−1 for (1) and 2.5 × 104 M−1 for (2) in 5 mM Tris-HCl/50 mM NaCl buffer at pH 7.2, respectively. The large enhancement in the relative viscosity of DNA on binding to the bnp supports the proposed DNA binding modes. The oxidative cleavage and photo-cleavage activity of complexes (1) and (2) were studied. The photo-induced DNA cleavage activities of the complexes in the presence and absence of d...