The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform

Jean Roncali - One of the best experts on this subject based on the ideXlab platform.

Devarapaga Madhu - One of the best experts on this subject based on the ideXlab platform.

  • synthesis and evaluation of stearic acid based heterocyclic schiff bases as biolubricant additives in epoxy karanja fatty acid 2 ethyl hexyl esters base oil
    Industrial Crops and Products, 2021
    Co-Authors: Venkateshwarlu Kontham, K R Ansari, Korlipara V Padmaja, Devarapaga Madhu
    Abstract:

    Abstract Four novel stearic acid derived Schiff bases containing heterocyclic aromatic groups (furan, Thiophene, pyrrole and pyridine) were synthesized in a three step reaction procedure. All the products were characterized by FT-IR, NMR and ESI-MS. The lubricity and antioxidant properties of synthesized Schiff bases were evaluated with 4-ball machine and differential scanning calorimeter. The morphologies and composition of elements on the worn surfaces were studied by using scanning electron microscope and energy-dispersive X-ray spectroscopy. Results show that these stearic acid based Derivatives possess good tribological properties and antioxidant performance. The difference in the additive performance of the Derivatives is closely related to the difference in their molecular structure. Pyridine containing Schiff base was more effective as both antiwear and extreme pressure additive while Thiophene Derivative exhibited higher efficacy as antioxidant.

Namita Roy Choudhury - One of the best experts on this subject based on the ideXlab platform.

  • sulfonated Thiophene Derivative stabilized aqueous poly 3 hexylThiophene phenyl c61 butyric acid methyl ester nanoparticle dispersion for organic solar cell applications
    ACS Applied Materials & Interfaces, 2018
    Co-Authors: Surya Subianto, Rajkamal Balu, Liliana De Campo, Anna Sokolova, Naba K Dutta, Namita Roy Choudhury
    Abstract:

    Aqueous dispersions of poly(3-hexylThiophene):phenyl-C61-butyric acid methyl ester (P3HT:PCBM) nanoparticles (NPs) have been fabricated using a Thiophene-based surfactant 2-(3-thienyl)ethyloxybutylsulfonate sodium salt (TEBS) for the first time via the mini-emulsion process. The use of TEBS resulted in a stable colloidal dispersion of P3HT:PCBM NPs, of which the effect of various fabrication parameters is investigated. The fabricated NPs were characterized by dynamic light scattering, scanning electron microscopy, UV-visible spectroscopy, contrast-variation small and ultra-small angle neutron scattering, and cyclic voltammetry. The internal structure and electrochemical performance of TEBS-stabilized P3HT:PCBM NPs were compared to those of sodium dodecyl sulfate-stabilized core-shell (PCBM-P3HT) NPs at the same surfactant concentration. Neutron scattering and cyclic voltammetry results reveal a homogeneous distribution of small de-mixed P3HT and PCBM domains in the internal structure of TEBS-stabilized P3HT:PCBM NPs, reminiscent of cast film. Moreover, electron microscopy images show evidence of diffused NP surface/interface upon drying (without annealing), which indicates that the Thiophene-containing TEBS may improve compatibility and film-forming properties of fabricated P3HT:PCBM NPs, and consequently be more suited for conventional film-processing methods for organic solar cell applications.

Takayoshi Kobayashi - One of the best experts on this subject based on the ideXlab platform.

  • Ultrafast spectroscopy of poly-Thiophene Derivative by using sub-10 fs visible pulse
    Conference on Lasers and Electro-Optics 2012, 2012
    Co-Authors: Atsushi Yabushita, Yu Hsien Lee, Chain-shu Hsu, Sheng-hsiung Yang, Chih-wei Luo, Takayoshi Kobayashi
    Abstract:

    Ultrafast spectroscopy was performed for a poly(3-hexylThiophene) (P3HT) film changing pump power. The result clarified the femtosecond time constant for generation and relaxation of the bound polaron pair in the film.

  • classification of dynamic vibronic couplings in vibrational real time spectra of a Thiophene Derivative by few cycle pulses
    Journal of Physical Chemistry A, 2007
    Co-Authors: Takayoshi Kobayashi, Zhuan Wang, Tetsuo Otsubo
    Abstract:

    Pump-probe spectroscopy was performed with a few cycle pulses of 6.7 fs duration. The electronic transition intensity modulation was induced by molecular vibration in a quinoid Thiophene molecule in solution. The real-time vibrational features were analyzed in terms of dependence of vibrational amplitude and phase on probe photon energy. The electronic transition probability is modulated by molecular vibration via vibronic coupling. Changes in the spectral shape and intensity of the time-resolved spectrum were studied by tracking characteristic spectral features including the peak frequency and intensity, spectral bandwidth, and band-integrated intensity. From the analysis the modulation mechanisms were classified into two groups: (1) Condon type and (2) non-Condon type. The features of the wave packet motions were also classified into zeroth-order Derivatives due to quasi-pure non-Condon type and first- and second-order Derivative types due to the displacement of the potential minimum and the potential curvature change associated with the relevant vibronic transition, respectively.

  • sub 5 fs spectroscopy of a Thiophene Derivative with a quinoid structure
    Chemical Physics Letters, 2006
    Co-Authors: Takayoshi Kobayashi, Haibo Wang, Zhuan Wang, Tetsuo Otsubo
    Abstract:

    Abstract Sub-5-fs spectroscopy of a Thiophene Derivative with an electron donative and an acceptive moieties and quinoid structure provided the experimental evidence of dynamic mode coupling. It was shown that two out-of-plane bending modes mediate the dynamic mode coupling between 1469 and 1379 cm−1 and between 1603 and 1469 cm−1. These couplings are considered to be associated with geometrical relaxation relevant to the neutral bipolaron formation in all-s-trans polyacetylene.

Venkateshwarlu Kontham - One of the best experts on this subject based on the ideXlab platform.

  • synthesis and evaluation of stearic acid based heterocyclic schiff bases as biolubricant additives in epoxy karanja fatty acid 2 ethyl hexyl esters base oil
    Industrial Crops and Products, 2021
    Co-Authors: Venkateshwarlu Kontham, K R Ansari, Korlipara V Padmaja, Devarapaga Madhu
    Abstract:

    Abstract Four novel stearic acid derived Schiff bases containing heterocyclic aromatic groups (furan, Thiophene, pyrrole and pyridine) were synthesized in a three step reaction procedure. All the products were characterized by FT-IR, NMR and ESI-MS. The lubricity and antioxidant properties of synthesized Schiff bases were evaluated with 4-ball machine and differential scanning calorimeter. The morphologies and composition of elements on the worn surfaces were studied by using scanning electron microscope and energy-dispersive X-ray spectroscopy. Results show that these stearic acid based Derivatives possess good tribological properties and antioxidant performance. The difference in the additive performance of the Derivatives is closely related to the difference in their molecular structure. Pyridine containing Schiff base was more effective as both antiwear and extreme pressure additive while Thiophene Derivative exhibited higher efficacy as antioxidant.