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991.
Dr. Bhavana Gupta Mariana C. Afonso Dr. Lin Zhang Dr. Cedric Ayela Patrick Garrigue Dr. Bertrand Goudeau Prof. Alexander Kuhn 《Chemphyschem》2019,20(7):941-945
Combining the actuation of conducting polymers with additional functionalities is an interesting fundamental scientific challenge and increases their application potential. Herein we demonstrate the possibility of direct integration of a miniaturized light emitting diode (LED) in a polypyrrole (PPy) matrix in order to achieve simultaneous wireless actuation and light emission. A light emitting diode is used as a part of an electroactive surface on which electrochemical polymerization allows direct incorporation of the electronic device into the polymer. The resulting free-standing polymer/LED hybrid can be addressed by bipolar electrochemistry to trigger simultaneously oxidation and reduction reactions at its opposite extremities, leading to a controlled deformation and an electron flow through the integrated LED. Such a dual response in the form of actuation and light emission opens up interesting perspectives in the field of microrobotics. 相似文献
992.
Debapriya Gupta Ankit Kumar Gaur Pravesh Kumar Himanshu Kumar Anjali Mahadevan Dr. Sudha Devi Dr. Saonli Roy Dr. Sugumar Venkataramani 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3463-3472
Light-responsive molecular systems with multiple photoswitches in C3-symmetric designs have enormous application potential. The design part of such molecular systems is critical due to its influence in several properties associated with the photoswitches. In order to tune, and in the evaluation of the design–property relationship, we synthesized 18 tripodal systems with variations in the core, linkers, connectivity, and azo(hetero)arene photoswitches. Through extensive spectroscopic and computational studies, we envisaged the factors controlling near-quantitative photoisomerization in both the directions (bistability) and the thermal stability of the metastable states. Furthermore, we also evaluated the impact of designs in obtaining reversible photo-responsive sol-gel phase transitions, solvatochromism, photo- and thermochromism. 相似文献
993.
Ghalib R. M. Mehdi S. H. Malla A. M. Alam M. G. Novaković S. B. Gupta A. K. Alzahrani H. A. H. 《Russian Journal of Organic Chemistry》2021,57(12):2018-2023
Russian Journal of Organic Chemistry - 3a,8a-Dihydroxy-2,8-dioxo-1,3a,8,8a-tetrahydro-2H-indeno[1,2-d]imidazole-3-carboxamide has been synthesized in 85% yield from ninhydrin and biuret via a green... 相似文献
994.
995.
Karki Surya B. Gupta Tripti Thapa Yildirim-Ayan Eda Eisenmann Kathryn M. Ayan Halim 《Plasma Chemistry and Plasma Processing》2020,40(1):99-117
Plasma Chemistry and Plasma Processing - Non-thermal plasma has been a promising new cancer treatment modality in plasma oncology field. It generates extracellular and intracellular reactive... 相似文献
996.
Vishnu Chauhan T. Gupta Paramjit Singh P.D. Sahare N. Koratkar Rajesh Kumar 《Physics letters. A》2019,383(9):898-907
The calibrated and controlled swift heavy ions (SHI) beam irradiation generate defects which can cause modifications in various properties of the materials such as structural, optical, magnetic, morphological, and chemical etc. The passage of ion through the target material causes the nuclear energy losses () and electronic energy losses (). The dominates over in SHI irradiation. In the present study, ZrO2 thin films were grown on silicon and glass substrate by using RF sputtering deposition technique. For the purpose of modifications induced by swift heavy ions, these films were irradiated by a 120 MeV S9+ ion beam of 1 pnA current, with varying ion fluences from 5E12 to 1E13 ions/cm2, using the tandem accelerator at the Inter University Accelerator Center (IUAC), New Delhi, India. The X-ray diffraction (XRD) patterns confirmed the formation of monoclinic and tetragonal phases and it was observed that XRD peaks intensity increased up to the fluence of 5E12 ions/cm2 followed by opposite behavior at higher fluences. Atomic force microscope (AFM) study revealed the increased surface roughness after SHI irradiation. In addition to it, the formation of electronic transition states in optical band gap region and enhancement of absorption edge was observed from UV-visible spectroscopy (UV-Vis) results due to which direct band gap energy value decreased from those of un-irradiated samples. Photoluminescence (PL) broad emission spectra were determined using the excitation wavelength at 290 nm with the prominent peak at 415 nm which can be ascribed to Zr vacancies due to band edge emission as a result of free-exciton recombination. Rutherford backscattering spectrometry (RBS) technique was used for depth profiling and elemental composition in zirconia thin films. The expected role of electronic energy loss during ion irradiation is to modify the properties of the material has been discussed. 相似文献
997.
998.
Patrick Das Gupta 《Pramana》2004,63(4):877-882
Discussions related to gravitational wave experiments viz. LIGO and LISA as well as to observations of supermassive black
holes dominated the workshop sessions on gravitational waves and relativistic astrophysics in the ICGC-2004. A summary of
seven papers that were presented in these workshop sessions has been provided in this article. 相似文献
999.
Jatinder N.D. Gupta Christos P. Koulamas George J. Kyparisis Chris N. Potts Vitaly A. Strusevich 《Annals of Operations Research》2004,129(1-4):171-185
This paper considers a variant of the classical problem of minimizing makespan in a two-machine flow shop. In this variant, each job has three operations, where the first operation must be performed on the first machine, the second operation can be performed on either machine but cannot be preempted, and the third operation must be performed on the second machine. The NP-hard nature of the problem motivates the design and analysis of approximation algorithms. It is shown that a schedule in which the operations are sequenced arbitrarily, but without inserted machine idle time, has a worst-case performance ratio of 2. Also, an algorithm that constructs four schedules and selects the best is shown to have a worst-case performance ratio of 3/2. A polynomial time approximation scheme (PTAS) is also presented. 相似文献
1000.
Let G be a finitely generated torsion-free group, which is a metabelian product of Abelian groups. We establish a criterion for endomorphisms satisfying some extra restriction to be invertible in G. Test sets for IA-endomorphisms of G are described and its test rank computed. 相似文献