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791.
Glass fiber reinforced polymer composite (GFRP) encounter many practical situations during its application, exposed to different temperature fluctuation. Absorption of moisture and the fluctuated thermal environment cause mechanical degradation of GFRP. The current plan is to explore the mechanical and chemical behavior of pristine multiwall carbon nanotubes(pMWCNTs)-glass fiber strengthens epoxy composites during thermal shock (TS). The laminates were prepared by the hand-lay-up process followed by compression molding. The thermal shock was performed at the temperature for the required samples was 135°C for 24 h, followed by −135°C for 24 h. A flexural test has been carried out at 1 mm/min loading speed. 0.2 wt% pMWCNTs filled nanocomposite appeared to have the highest flexural strength and modulus compared to ambient samples. The thermomechanical behavior of nanocomposites has been accomplished by analyzing the dynamic mechanical thermal analysis graph (DMTA). Field emission scanning electron microscope (FESEM) analyzed the fracture surface of in-situ mechanical failure samples to find out the primary failure modes for strengthening and weakening mechanisms. The glass transition temperature (Tg) of the nanocomposite observed decreased due to homogeneous dispersion of pMWCNTs, imparting some effect on crosslink density and reinforcement up to 0.2 wt%. This study reveals that the uniform distribution of pMWCNTs and thermal shock treatment enhances the matrix stiffness and improves the mechanical properties. 相似文献
792.
Rens Kamphorst Kaiqiao Wu Samir Salameh Gabrie M. H. Meesters J. Ruud van Ommen 《加拿大化工杂志》2023,101(1):227-243
The fluidization of cohesive powders has been extensively researched over the years. When looking at literature on the fluidization of cohesive particles, one will often find papers concerned with only micro- or only nano-sized powders. It is, however, unclear whether they should be treated differently at all. In this paper, we look at differences and similarities between cohesive powders across the size range of several nanometres to 10s of micrometres. Classification of fluidization behaviour based on particle size was found to be troublesome since cohesive powders form agglomerates and using the properties of these agglomerates introduces new problems. When looking at inter-particle forces, it is found that van der Waals forces dominate across the entire size range that is considered. Furthermore, when looking into agglomeration and modelling thereof, it was found that there is a fundamental difference between the size ranges in the way they agglomerate. Where the transition between the types of agglomeration is located is, however, unknown. Finally, how models are made and agglomerate sizes are measured is currently insufficient to accurately predict or measure their sizes consistently. 相似文献
793.
Ariane Borges Chi Nguyen Madison Letendre Iryna Onasenko Rene Kandler Ngoc K. Nguyen Jue Chen Tamara Allakhverdova Emily Atkinson Bella DiChiara Caroline Wang Noa Petler Henna Patel Dr. Dhaval Nanavati Dr. Samir Das Prof. Dr. Arundhati Nag 《Chembiochem : a European journal of chemical biology》2023,24(4):e202200590
While most FDA-approved peptide drugs are cyclic, the robust cyclization chemistry of peptides and the deconvolution of cyclic peptide sequences by using tandem mass spectrometry render cyclic peptide drug discovery difficult. Here we present the successful design of cyclic peptides on solid phase that addresses both of these problems. We demonstrate that this peptide cyclization method using dichloro-s-tetrazine on solid phase allows successful cyclization of a panel of random peptide sequences with various charges and hydrophobicities. The cyclic peptides can be linearized and cleaved from the solid phase by simple UV light irradiation, and we demonstrate that accurate sequence information can be obtained for the UV-cleaved linearized peptides by using tandem mass spectrometry. The tetrazine linker used in the cyclic peptides can further be explored for inverse electron-demand Diels-Alder (IEDDA) reactions for screening or bioconjugation applications in the future. 相似文献
794.
Susmita Mondal Nivedita Pan Ria Ghosh Arpan Bera Dipanjan Mukherjee Tuhin Kumar Maji Anirudddha Adhikari Sangeeta Ghosh Prof. Chinmoy Bhattacharya Prof. Samir Kumar Pal 《ChemMedChem》2022,17(14):e202100660
This study explores a combined electrochemical and spectroscopic approach to investigate the degradation of bilirubin, a molecular marker of jaundice in humans using a biocompatible nanohybrid (citrate-functionalized Mn3O4 nanohybrid; C−Mn3O4 NH). The approach is aimed at the development of a facile theranostic tool for treatment, detection, and prognosis of jaundice. Linear sweep voltammetry (LSV) studies on bilirubin, C−Mn3O4 NH, a model carrier protein, and its complex with bilirubin reveal the efficacy of the nanohybrid for both degradation and detection of bilirubin. Furthermore, spectroscopic studies depict that distal electron transfer to be the probable mechanism behind the observed bilirubin degradation in physiological milieu. 相似文献
795.
Labiod Samir Smaani Billel Tayal Shubham Rahi Shiromani Balmukund Sedrati Hichem Latreche Saida 《SILICON》2023,15(3):1181-1191
Silicon - Within this paper, a total optoelectronic simulation of a PIN photodiode structure was presented. The microlens structure has been introduced on the top of the PIN photodiode to... 相似文献