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In the present investigation, we report an efficient, direct, one-pot synthesis of mononuclear, mono(bis(2-(4-butylphenyl)imino)methyl)phenoxy)zinc(II)dichloride complex (C34H38Cl2N2O2)Zn in ethanol. The synthesized coordination compound was subjected to crystal growth by repeated recrystallization in ethanol at ambient temperature. The title compound was thoroughly characterized by 1H NMR, 13C NMR, FT-IR and Mass spectral studies. The crystal structure of the Zinc complex was established by single crystal X-ray diffraction studies. The title compound is mononuclear, with tetragonal coordination geometry and P41212 space group stabilised by intermolecular (C H…Cl) and intramolecular hydrogen bonding (N-H…..O). The zinc coordination complex exhibits photoluminescence property with strong emission at 525 nm in the green region. The molecular docking studies by using Gold suite software reveal that the Zinc complex has strong binding affinity towards α-glucosidase enzyme with Goldscore of 83.76 and forms two hydrogen bonds (LEU208, TRY2) with bond length (3.31, 3.73 A) and one electrostatic bond (LYS 208) of bond length (4.51) with the target enzyme. Mono(bis(2-(4-butylphenyl)imino)methyl)phenoxy)zinc(II) dichloride complex exhibited IC50 value of 3.0454 ± 0.010 µM as compared to standard acarbose (IC50 = 0.5414 µM). Thus the title zinc complex is a promising candidate for α-glucosidase inhibition after necessary biological and pharmaceutical investigations.

Tooth wear is considered to be one of the major causes of failure modes in gearing systems. The achieved service life of the geared unit mainly depends on the gear tooth strength and surface wear. Excessive wear is characterized by loss of tooth profile, which results in high noise and vibration, a minor loss of conjugate action and a reduction in efficiency. Hence, enhancement of gear life against wear becomes an important requirement for effective design detailing of gears. This article presents an idea to minimize the wear of the gear teeth by adopting non-standard gear. Non-standard gear is defined as one whose tooth thickness at the pitch circle is not equal to 0.5πm. In this study, the impact of the tooth thickness coefficient on tooth wear for standard and non-standard spur gears is numerically investigated. The non-standard tooth thickness in the pinion leads to enhancement of the tooth strength and leading to reduction of tooth wear. Finally, the influence of gear parameters such as gear ratio, pressure angle and pinion teeth number on wear depth, for non-standard pinion and gear has been investigated and the results of the parametric study are discussed.

Due to the emergence of renewable energy sources into the power system, the need for Energy Storage System (ESS) becomes more significant. Hence, parallel operation of Battery Energy Storage System (BESS) is an influential application in microgrids. The quazi Z source inverter (qZSI) is a single stage converter. It has two controllable DC ports which are connected with batteries. These batteries are charged by photovoltaic energy. This volatile nature leads to an unequal voltage and current supply to batteries. Hence a proper control strategy which is applicable to both islanded and grid connected mode is to be implemented in this proposed work. To execute this and to harvest maximum power from solar systems, the proposed control strategy, the Maximum Power Point Tracking (MPPT) schemes are employed. This will ensure maximal conversion efficiency. In this paper, implementation methodology and the results of parallel operation of two batteries supplied by renewable energy source are done in the MATLAB / SIMULINK environment. A test prototype is also developed to justify the effective operation of proposed system

The second order nonlinear optical material and the single crystal of 2,5-Dimethyl-N-(3-phenylprop-2-en-1-ylidene) aniline (2,5 DPPA) which is organic in character was well synthesised by the standard slow evaporation method. The crystalline structure of 2,5 DPPA studied by single crystal XRD analysis confirmed that the material belongs to the orthorhombic crystal system with non-centrosymmetric space group P212121. Functional groups were analyzed by Fourier transforms infrared analysis. The calculated optical band gap was found to be 2.76 eV. The second harmonic generation of 2,5 DPPA crystal was confirmed by Kurtz–Perry powder test using the source of Nd:YAG laser and found that it is 1.25 times greater than that of reference KDP material. Thermal stability of the titled crystal was studied by TGA/DTA technique. The Vicker’s hardness (Hv) test portrays that the mechanical resistance of the crystal’s hardness coefficient value is 2. The dielectric constant and dielectric loss of the grown crystal decreases with increase in array of the line of value of the frequencies.

The proposed scheme implements TiOISSS with meaningful shadows.The proposed scheme uses additional authentication image, to enhance the security.Adaptive halftoning is used to improve the quality of decoded secret image.The proposed scheme demonstrates better quality and security. Visual Cryptography Scheme (VCS) is a cryptographic technique for protecting secret images. The advantage of using VCS is that decoding can be done without use of any computations. Nevertheless, the reconstructed image has poor visual quality. Therefore, Two in One Image Secret Sharing Scheme (TiOISSS) was proposed which takes the advantage of VCS and provides good quality decoded images. However, the existing TiOISSS has security limitations as it is implemented only for noisy shadows. Hence, in this paper, modified TiOISSS is proposed and implemented for meaningful shadows. To enhance the security of the shares and prevent fake shares that may be introduced by hackers, an authentication image is shared along with the secret image. The quality of the reconstructed image is improved by using adaptive halftoning technique. Experimental results demonstrate the improved security and quality by the proposed scheme.

An organic nonlinear optical single crystal of 4-(E)-1-(4-chlorophenyl)-3-(4-nitrophenyl) prop-2-en-1-one [CPNP] was synthesized and its single crystal grown by solution growth technique. XRD analysis of the CPNP single crystal confirms that the crystal belongs to orthorhombic system with non centrosymmetric space group Pna21. The characteristic functional groups in the crystal were identified by FT-IR analysis. The CPNP crystal exhibits an optical transparency of 76% with optical band gap energy of 2.88eV. The HOMO-LUMO energy gap calculated from DFT for a single-molecule in the gas phase was found to be 3.88 eV. The thermal stability of the CPNP crystal was analyzed by TGA/DSC analysis. The CPNP crystal exhibits photoluminescence property with strong emission at 615nm in the orange red region. The LDT value of the CPNP crystal was found to be 1.72 GW/cm2. The SHG efficiency of CPNP crystal is 0.75 times greater than that of standard urea.

The blue light emitting materials based on a fluoro phenanthro [9,10-d] imidazole derivatives prepared by a facial synthetic process exhibit good thermal stability, highly efficient fluorescence and balanced carrier injection. The multi-layered device based on fluoro phenanthroimidazole derivatives shows a higher luminance in a lower turn-on voltage. The device performance implies that the phenanthroimidazole unit is an excellent building block for tuning the carrier injection properties as well as blue emission.

A new fluorophore 2-(4-fluorophenyl)-1-phenyl-1H-phenanthro [9,10-d]imidazole has been synthesized and characterized by spectroscopic techniques. Nanoparticulate ZnO enhances the fluorescence of the synthesised fluorophore. The absorption, fluorescence, lifetime, cyclic voltammetry and infrared studies reveal that fluorophore is attached to the surface of ZnO semiconductor. Photo-induced electron transfer (PET) explains the enhancement of fluorescence by nanoparticulate ZnO and the apparent binding constant has been obtained. Adsorption of the fluorophore on ZnO nanoparticle lowers the HOMO and LUMO energy levels of the fluorophore. The strong adsorption of the phenanthrimidazole derivative on the surface of ZnO nanocrystals is likely due to the chemical affinity of the nitrogen atom of the organic molecule to the zinc ion on the surface of nanocrystal.

A new kind of fluorophore 2-(4-fluorophenyl)-1-phenyl-1H-phenanthro [9,10-d] imidazole has been synthesized and characterized by 1 H NMR, 13 C NMR and mass spectral studies. The dynamics of photoinduced electron injection and energy transfer from phenanthroimidazole to CuO, ZrO 2 , WO 3 and Al 2 O 3 nanocrystals has been studied by Fourier transform infrared spectroscopy (FT-IR), absorption, fluorescence and lifetime spectroscopic methods. The association between nanocrystals and phenanthroimidazole is explained by both absorption and fluorescence quenching data. The distance between phenanthroimidazole and nanocrystals as well as the critical energy transfer distance has been obtained. The free energy change (Δ G et ) for electron injection has also been deduced. Qualitative relationship exists between the efficiency of binding with the LUMO – CB energy gap and also the efficiency of binding with the HOMO – CB energy gap.

A new type of emitter 2-(4-fluorophenyl)-1-phenyl-1H-phenanthro [9,10-d] imidazole has been designed and synthesized. Absorption, emission, FT-IR and lifetime spectroscopies have been used to investigate the binding of phenanthroimidazole molecule with the nanoparticulate anatase and rutile TiO2. The fluorescence emission of the phenanthroimidazole is quenched effectively by anatase particulate TiO2 due to charge injection from the excited singlet state of phenanthroimidazole to the conduction band of the TiO2 nanocrystals. Surprisingly, nanocrystalline rutile enhances the fluorescence. This is because of lowering of LUMO and HOMO energy levels of phenanthroimidazole molecule. Electron injection from photoexcited phenanthroimidazole to conduction band of rutile TiO2 ( S → S + + e − C B ) is likely to enhance the fluorescence. The HOMO and LUMO energies of phenanthroimidazole are deduced from cyclic voltammetric results. To support the experimental results DFT calculation has been made for Gaussian-03.

A new type of fluorophore 2-(naphthalen-1-yl)-1-((naphthalen-1-yl)methyl)-1H-benzimidazole (NNMB) has been prepared and characterized by 1 H NMR, 13 C NMR, mass and IR spectral analysis. Absorption, fluorescence and synchronous fluorescence spectral studies have been made for the mutual interaction of NNMB with bovine serum albumin (BSA). Absorption spectroscopy proved the formation of a ground state BSA…NNMB complex. Fluorescence spectrum of BSA in the presence of NNMB clearly shows that NNMB acts as a quencher. Based on the theory of Forester’s non-radiation energy transfer (FRET) binding distance has been deduced. The Stern–Volmer quenching constant ( K SV ), binding site number ( n ), apparent binding constant ( K A ) and corresponding thermodynamic parameters (Δ G , Δ H and Δ S ) were determined.

Heterocyclic phenanthrimidazole derivative, 2-(4-fluorophenyl)-1-p-tolyl-1H-imidazo[4,5-f] [1,10] phenanthroline (FPTIP) has been synthesized and characterised by NMR, mass and CHN analysis. The FPTIP was evaluated concerning their solvatochromic properties and molecular optical nonlinearities. Their electric dipole moment (μ), polarizability (α) and hyperpolarizability (β) have been calculated theoretically and the results indicate that the extension of the π-framework of the ligands has an effect on the NLO properties. The energies of the HOMO and LUMO levels and the molecular electrostatic potential (MEP) energy surface studies have exploited the existence of intramolecular charge transfer (ICT) within the molecule.

The interaction between 2-(4-fluorophenyl)-1-phenyl-1H-phenanthro [9,10-d] imidazole (FPPI) and bovine serum albumin (BSA) was investigated by fluorescence spectral studies. The observed experimental result shows that the imidazole derivative has strong ability to quench the fluorescence of BSA by forming complex which is stabilized by electrostatic interactions. The effective quenching constants ( K sv ) were 2.78 × 10 4 , 2.52 × 10 4 , and 2.32 × 10 4 at 301, 310, and 318 K respectively. The Stern–Volmer quenching constant ( K sv ), binding site number ( n ), apparent binding constant ( K A ) and corresponding thermodynamic parameters (Δ G , Δ H , and Δ S ) were calculated. The distance between the donor (BSA) and acceptor (FPPI) was obtained according to fluorescence resonance energy transfer (FRET). Conformational changes of BSA were observed from synchronous fluorescence technique. The effect of metal ions such as Cu 2+ , Zn 2+ , Ca 2+ , Mg 2+ , Ni 2+ , Co 2+ , and Fe 2+ on the binding constants between the FPPI and BSA were also studied.

It is a very big challenge to develop a Cu2+ selective fluorescent sensor with the ability to exclude the interference of some metal ions such as Fe3+, Mg2+, Ag+, K+ and Na+. Herein, we report a fluorescence quenching of some benzimidazole derivatives (1–6) with Cu2+ metal ion. These benzimidazole derivatives have been shown to bind copper ions resulting in quenching of its fluorescence. The response to Cu2+ is rapid, selective and reversible upon addition of a copper chelator. These benzimidazole derivatives were characterized by 1H, 13C NMR mass and elemental analysis. XRD analysis was carried out for 1-(4-methylbenzyl)-2-p-tolyl-1H-benzo[d]imidazole.