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51.
A comparative study on ballistic performance of hot pressed boron carbide (HPBC) and reaction bonded boron carbide (RBBC) tiles were performed using depth of penetration (DOP) configuration against 7.62?mm AP ammunition. Both HPBC and RBBC tiles were characterised for their phase contents and properties. Ballistic efficiency was calculated using the newly developed normalised ballistic efficiencies, normalised differential efficiency factor &; normalised ballistic efficiency, in order to eliminate the influence of backing material on ballistic efficiency. It was found that for similar tile thickness, the residual shot weight and residual DOP of HPBC tiles were lesser than that of RBBC tiles. Normalised ballistic efficiencies, for both HPBC and RBBC ceramics, showed a higher ballistic performance for HPBC than RBBC tiles. 相似文献
52.
Marble slurry derived hydroxyapatite as heterogeneous catalyst for biodiesel production from soybean oil 下载免费PDF全文
53.
K S Divy Athulya K Madhu T U Umadevi T Suprabh P. Radhakrishnan Nair Suresh Mathew 《半导体学报》2017,38(6):063002-8
In this paper an improvement in the photocatalytic performance of TiO2 was carried out via hybridizing with graphene. Graphene-TiO2 (GR-TiO2)nanocomposites with different weight addition ratios of graphene oxide (GO) have been prepared via a facile microwave irradiation of GO and tetrabutyl titanate in isopropyl alcohol. Raman spectroscopy (RS), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible spectroscopy (UV-vis), Fourier transform infrared spectra (FTIR), energy dispersive X-ray spectroscopy (EDX) and photoluminescence spectra (PL) are employed to determine the properties of the samples. Microwave irradiation can heat the reactant to a higher temperature in a short time, simultaneously GO is reduced to graphene and TiO2 nanoparticles grown on the surface of GR. GR-TiO2 nanocomposites synthesized via this approach have efficient electron conductivity in GR, resulting in a reduced electron-hole recombination rate. Among the synthesized nanocomposites, GT-8wt% exhibited the best photocatalytic activity toward photocatalytic degradation of MB. Our current work provides a new insight for the fabrication of GR-TiO2 nanocomposites within a short reaction time and also explains the mechanism of photocatalysis employing radical and hole scavengers. 相似文献
54.
Kattumuri V Katti K Bhaskaran S Boote EJ Casteel SW Fent GM Robertson DJ Chandrasekhar M Kannan R Katti KV 《Small (Weinheim an der Bergstrasse, Germany)》2007,3(2):333-341
Gold nanoparticles (AuNPs) have exceptional stability against oxidation and therefore will play a significant role in the advancement of clinically useful diagnostic and therapeutic nanomedicines. Despite the huge potential for a new generation of AuNP-based nanomedicinal products, nontoxic AuNP constructs and formulations that can be readily administered site-specifically through the intravenous mode, for diagnostic imaging by computed tomography (CT) or for therapy via various modalities, are still rare. Herein, we report results encompassing: 1) the synthesis and stabilization of AuNPs within the nontoxic phytochemical gum-arabic matrix (GA-AuNPs); 2) detailed in vitro analysis and in vivo pharmacokinetics studies of GA-AuNPs in pigs to gain insight into the organ-specific localization of this new generation of AuNP vector, and 3) X-ray CT contrast measurements of GA-AuNP vectors for potential utility in molecular imaging. Our results demonstrate that naturally occurring GA can be used as a nontoxic phytochemical construct in the production of readily administrable biocompatible AuNPs for diagnostic and therapeutic applications in nanomedicine. 相似文献
55.
AbstractIn this article, a three-time level finite difference scheme is used to resolve the dual phase lag’s (DPL) heat conduction in a micro scale gold film subjected to spontaneous temperature boundary conditions without knowing the heat flux. Finite difference analog of DPL equation on applying to the intermediate grid points of the computational domain results into a system of linear, algebraic equations which can be solved using Thomas’ algorithm to finally obtain the transient temperature solution distributions in the film. The solution predicted by the DPL model is compared with that obtained by the single-phase Cattaneo–Vernotte’s model. Further, the way in which non-Fourier’s temperature distributions affected by the diffusion due to the increase in Heat Conduction Model numbers agree with the predecessor’s published results. The results by both the models revealed a finite thermal wave speed in the film contrasting the infinite speed of heat propagation as stated by the classical Fourier’s thermal model. Low spatial step and higher order finite difference schemes are recommended for better accurate numerical results of the non-Fourier’s temperature distributions occurring in the very short transient period between the instants of the suddenly applied spatial temperature gradient and the reaching of the steady state conditions. 相似文献
56.
Madhu S. Pandey Chunlei Wang Scott Umlauf Shihua Lin 《International journal of molecular sciences》2021,22(21)
Bispecific antibodies (BsAbs) or fusion proteins (BsAbFPs) present a promising strategy for cancer immunotherapy. Numerous BsAbs targeting coinhibitory and costimulatory pathways have been developed for retargeting T cells and antigen presenting cells (APCs). It is challenging to assess the potency of BsAb that engages two different signaling pathways simultaneously in a single assay format, especially when the two antigen targets are expressed on different cells. To explore the potency of anti-PD-L1/CD40L BsAbFP, a fusion protein that binds to human CD40 and PD-L1, we engineered CHO cells as surrogate APCs that express T cell receptor activator and PD-L1, Jurkat cells with PD-1 and NFAT-luciferase reporter as effector T cells, and Raji cell with NFkB-luciferase that endogenously expresses CD40 as accessory B cells. A novel reporter gene bioassay was developed using these cell lines that allows anti-PD-L1/CD40L BsAbFP to engages both PD-1/PD-L1 and CD40/CD40L signaling pathways in one assay. As both reporters use firefly luciferase, the effects of activating both signaling pathways is observed as an increase in luminescence, either as a higher upper asymptote, a lower EC50, or both. This dual target reporter gene bioassay system reflects potential mechanism of action and demonstrated the ability of anti-PD-L1/CD40L BsAbFP to synergistically induce biological response compared to the combination of anti-PD-L1 monovalent monoclonal antibody and agonist CD40L fusion protein, or either treatment alone. The results also showed a strong correlation between the drug dose and biological response within the tested potency range with good linearity, accuracy, precision, specificity and stability indicating properties, suggesting that this “three-cell-in-one” dual target reporter gene bioassay is suitable for assessing potency, structure-function and critical quality attributes of anti-PD-L1/CD40L BsAbFP. This approach could be used for developing dual target bioassays for other BsAbs and antibodies used for combination therapy. 相似文献
57.
58.
Praveenkumara Jagadeesh Madhu Puttegowda Yashas Gowda Thyavihalli Girijappa Pradeep Shivanna Sanjay Mavinkere Rangappa Suchart Siengchin 《乙烯基与添加剂工艺杂志》2023,29(3):555-567
Structural uses in the vehicle, aerospace, and sporting goods industries are being supplanted by hybrid composites that utilized natural fibers as reinforcements. The main focus of this work is to fabricate and characterize the ramie, hemp, and kevlar fabric reinforced hybrid vinyl ester composites. The composite laminates were fabricated via economically feasible and flexible hand lay-up technique. Overall six composites were prepared by varying the stacking sequence, including both hybrid and non-hybrid composites. The prepared composites were subjected to physical analysis (density, void fraction), mechanical tests (tensile, flexural, interlaminar shear, and impact test), morphological analysis (scanning electron microscopy), and water absorption test. The hybrid composites exhibited lesser void percentage than the non-hybrid composites. The mechanical properties were maximum for kevlar fabric skinned with core natural fabric reinforced composites (L-5, L-6) due to hybridization of highly strengthened kevlar fabrics. Moreover, the number fabric layers reinforced to achieve the standard thickness also affected the mechanical properties. All composite morphologies exhibited the same failure characteristics, including transverse interlaminar shear cracking, microbuckling, and fiber rip. The texture of the Kevlar yarns is uniform, but the texture of the natural fabric yarns is relatively less uniform. In comparison to the salt water medium, the percentage of water absorbed by composites in normal and distilled water was greater. This is due to the presence and accumulation of salt particles on the surface of the materials, which inhibits the action of water molecules, resulting in a drop in the proportion. 相似文献
59.
The present study deals with preparing mixed matrix membranes (MMMs), a new polysaccharide-based natural polymer used as a matrix with functionalized carbon nanotubes (FCNTs) and graphene oxide (GO) used as an inorganic filler. This work identified the effect of the inorganic fillers (FCNTs or GO) with naturally occurring polymer for gas separation. The incorporation of fillers improves the gas separation performance of MMMs. In GG/FCNTs MMMs, the selectivities of CO2/N2 and CO2/H2 were enhanced by 55.24% and 57.89%, respectively. Moreover, in GG/GO MMMs, the selectivities of CO2/N2 and CO2/H2 were improved by 99.50% and 50%, respectively. The membrane was characterized by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). The SEM analysis of GG/GO MMMs reveals layered structure, and GG/FCNTs MMMs create passages to transport gases. The Universal testing machine (UTM) is used to analyze the mechanical properties of pristine and modified membranes. 相似文献
60.
Das Madhu Sudan Samanta Anu Sanyal Sourish Mandal Sanjoy 《Wireless Personal Communications》2021,120(4):3389-3413
Wireless Personal Communications - Mobile robot navigation has been a current issue in the most recent two decades. Mobile robots are necessary to explore in obscure and dynamic situations. To... 相似文献