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61.
Electrochemical treatment and galvanic coupling are some of the possible modes of acceleration of low temperature phosphating process. The cathodic and anodic treatments during phosphating influence the deposition mechanism, characteristic properties and the corrosion resistance of the resultant coatings in a different way. The present paper aims to compare these aspects and to identify the possible applications of phosphate coatings obtained by these treatments.  相似文献   
62.
This paper presents a complete thermal analysis of a novel conformal surface thermometer design with directional sensitivity for real-time temperature monitoring during hyperthermia treatments of large superficial cancer. The thermal monitoring sheet (TMS) discussed in this paper consists of a 2-D array of fiberoptic sensors embedded between two layers of flexible, low-loss, and thermally conductive printed circuit board (PCB) film. Heat transfer across all interfaces from the tissue surface through multiple layers of insulating dielectrics surrounding the small buried temperature sensor and into an adjacent temperature-regulated water coupling bolus was studied using 3-D thermal simulation software. Theoretical analyses were carried out to identify the most effective differential TMS probe configuration possible with commercially available flexible PCB materials and to compare their thermal responses with omnidirectional probes commonly used in clinical hyperthermia. A TMS sensor design that employs 0.0508-mm Kapton MTB and 0.2032-mm Kapton HN flexible polyimide films is proposed for tissue surface thermometry with low influence from the adjacent waterbolus. Comparison of the thermal simulations with clinical probes indicates the new differential TMS probe design to outperform in terms of both transient response and steady-state accuracy in selectively reading the tissue surface temperature, while decreasing the overall thermal barrier of the probe between the coupling waterbolus and tissue surface.   相似文献   
63.
Drug‐resistant tuberculosis is being increasingly recognized and is one among the leading cause of death worldwide. Remarkable impermeability of cell wall to antituberculous drugs protects the mycobacteria from drug action. The present study analyzed the cell wall thickness among first‐line drug resistant and sensitive Mycobacterium tuberculosis (Mtb) isolated from cerebrospinal fluid by transmission electron microscopy (TEM). The average thickness of the cell wall of sensitive isolates was 13.60 ± 0.98 nm. The maximum difference (26.48%) in the cell wall thickness was seen among multi‐drug resistant (18.50 ± 1.71 nm) isolates and the least difference (4.14%) was shown by streptomycin‐resistant (14.18 ± 1.38 nm) isolates. The ultrastructural study showed evident differences in the cell wall thickness among sensitive and resistant isolates. Preliminary TEM examination of cells indicates that morphological changes occur in the cell wall which might be attributed to the drug resistance. The thickened wall of Mtb appears to help the bacilli to overcome the action of antituberculous drugs.  相似文献   
64.
Sakthivelu  S.  Sethusundaram  P. P.  Ravichandran  M.  Meignanamoorthy  M. 《SILICON》2021,13(4):1285-1294
Silicon - Aluminium alloy finds widespread applications in numerous engineering industries because of its tremendous properties. However aluminium alloy possess poor wear resistance. This study...  相似文献   
65.
Kumar  S. Dinesh  Ravichandran  M. 《SILICON》2018,10(6):2653-2662
Silicon - In this work, AA7178-10 wt.% ZrB2 Metal Matrix Composite was produced using stir casting route and the mechanical properties of the composites were studied. The microstructure and...  相似文献   
66.
67.
Graphene oxide (GO) was covalently functionalized with poly(4‐vinyl pyridine) (P4VP) by atom transfer radical polymerization for drug delivery and antimicrobial applications. The physiochemical properties, chemical structure, composition and morphology of the P4VP‐functionalized GO (GO‐P4VP) were studied. Simple physisorption of a cancer drug, camptothecin (CPT), via π ? π stacking and/or hydrophobic interactions on the GO‐P4VP was tested for drug loading and its release by altering the pH. The GO‐P4VP has low cytotoxicity, and the CPT‐loaded GO‐P4VP exhibited a high potency for killing cancer cells in vitro. Prominent antimicrobial properties against Escherichia coli and Staphylococcus aureus were also observed. Thus, the GO‐P4VP can be utilized as a drug delivery vector with high biocompatibility, solubility and stability in physiological solutions, a suitable payload capacity and excellent bacterial toxicity. Owing to its small size, low cost, large specific area, ready scalability and useful non‐covalent interactions, GO‐P4VP is a novel material for biomedical, industrial and environmental applications. © 2015 Society of Chemical Industry  相似文献   
68.
Krishankumar  R.  Sivagami  R.  Saha  Abhijit  Rani  Pratibha  Arun  Karthik  Ravichandran  K. S. 《Applied Intelligence》2022,52(12):13497-13519
Applied Intelligence - The role of cloud services in the data-intensive industry is indispensable. Cision recently reported that the cloud market would grow to 55 billion USD, with an active...  相似文献   
69.
The performance of cyber physical system–based smart wireless networks depends on effective channel access by reducing the blocking, the dropping probability, and collisions. The aim of this proposed algorithm is to reduce the collisions in cyber physical system–based smart wireless networks. In this paper, multilevel medium access control in cyber physical system–based smart wireless networks is proposed. The optimal number of levels of gateways is determined using the concept of learning automata. Priority and time limit are assigned to every packet that is being transmitted. The proposed algorithm is evaluated and compared with two‐level medium access control in cyber physical system–based smart wireless networks, which is referred as priority with counter modified backoff (PCMB). The parameters used for evaluating the performance are throughput, delay, % of collisions, and number of packets dropped. The results project that the proposed algorithm accomplishes improved performance than PCMB.  相似文献   
70.
Pure and Fe doped ZnO nanoparticles were prepared by a facile and cost-effective co-precipitation method. The X-ray diffractograms (XRD) reveal that the grown nanoparticles are hexagonal in structure and the crystallite sizes are in the range of 27–28 nm. The transmission electron microscope (TEM) micrographs confirmed the spherical nature of the grown particles and the Fourier transform-infrared (FT-IR) studies confirmed the presence of Zn–O bonding in the prepared nanoparticles. Additionally, the presence of the constituent elements is confirmed with XPS analysis. The optical bandgap of the prepared nanoparticles are calculated as 3.28, 3.19 and 3.08 eV for ZnO, ZnO–Fe 10 at.% and ZnO–Fe 20 at.%, respectively. The photocatalytic dye degradation efficiency against methylene blue, is 68.52, 73.96, and 87.92, respectively. To validate the photocatalytic activity, a DFT based calculation was performed to measure the band edge positions of the pure and Fe doped ZnO nanostructures, and the obtained results are well supported by the experimental results.  相似文献   
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