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41.
Wireless Personal Communications - In recent years, cloud computing plays a significant role in offering several applications with high-level reliability, availability, and security as well as...  相似文献   
42.
Porous high surface area thin films of nanosheet-shaped monoclinic MoO(3) were deposited onto platinized Si substrates using patch antenna-based atmospheric microplasma processing. The films were characterized by high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM) and electrochemical analysis. The electrochemical analysis shows original redox peaks and high charge capacity, and also indicates a reversible electrochemical behaviour particularly beneficial for applications in Li-ion batteries. SEM shows that the films are highly porous and consist of nanosheets 50-100 nm thick with surface dimensions in the micrometre range. HRTEM reveals that the MoO(3) nanosheets consist of the monoclinic beta phase of MoO(3). These intricate nanoarchitectures made of monoclinic MoO(3) nanosheets have not been studied previously in the context of applications in Li-ion batteries and show superior structural and morphological features that enable effective insertion of Li ions.  相似文献   
43.
Acid soluble collagen (ASC) and pepsin-soluble collagen (PSC) from the outer skin waste of marine eel fish (Evenchelys macrura) were isolated and characterized. The prepared collagen was used to test its effective drug delivering potential in vitro condition. Present results were confirmed as collagen by different physico-chemical techniques like SDS-PAGE, HPLC, FTIR and SEM. Further amino acid analysis corroborates isolation of type I collagen. Both ASC and PSC comprising two different α-chains (α 1 and α 2) were characterized as type I and contained imino acid of 190-200 residues, respectively. The denaturation temperatures (T(d)) of ASC and PSC were 38.5 and 35.0?°C, respectively, which is promising as an advantage for biomedical application due to closeness in T(d) to mammalian collagen. Furthermore, the gel and film forming capability of collagen samples containing implant standard antibiotic was proved to be a suitable drug delivering system.  相似文献   
44.
In this work, we have presented a spin-coating method to produce thin films started with pure BiCrO_3(BCO) and ended up with BiFeO_3(BFO) by increasing x values in the(BiFeO_3)_x–(BiCrO_3)_(1-x)composites. All the produced thin films have been crystallized at the annealing temperatures of 400 °C for 0.5 h. The XRD and EDAX spectrums give insight that the two crystal phases related to BCO and BFO stayed together within the thin film matrices. SEM analysis showed that the prepared composite had macroporous morphology with interconnected pores and its width(size) decreased with increasing x values. The strong correlations are observed among the microstructure, dielectric, ferroelectric, ferromagnetic properties and Fe concentration. Among all composites, the composition of 0.75 shows an attractive magnetization, polarization, switching and improved dielectric behaviors at room temperature. Significant increase in the multiferroic characteristics of 0.75 composition is due to arise of lower leakage current by causing reduction in oxygen vacancy density, and enhancement of super-exchange magnetic interaction between Fe~(3+) and Cr~(3+) at BFO/BCO interface layers. Our result shows that the thin layer on Pt(111)/Ti/SiO_2/Si substrate possesses simultaneously improved ferroelectric and ferromagnetic properties which make an inaccessible potential application for nonvolatile ferroelectric memories.  相似文献   
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46.
Scope : We hypothesized that curcumin, a potent anti‐oxidant, might be beneficial in ameliorating the development of diabetic nephropathy through inhibition of PKC‐α and PKC‐β1 activity‐ERK1/2 pathway. Methods and results : Diabetes was induced by a single intraperitoneal injection of streptozotocin (STZ) (55 mg/kg) in rats. Three weeks after STZ injection, rats were divided into three groups, namely, normal, diabetic and diabetic treated with curcumin at 100 mg/kg/day, p.o., for 8 wk. At 11 wk after STZ injection, diabetic rats exhibited renal dysfunction, as evidenced by reduced creatinine clearance, increased blood urea nitrogen (BUN) and proteinuria, marked increases in lipid peroxidation, NOX4 and p67phox and decrease in anti‐oxidant enzyme. All of these abnormalities were significantly reversed by curcumin. Furthermore, the high‐glucose‐induced PKC‐α and PKC‐β1 activities and phosphorylated ERK1/2 was significantly diminished by curcumin. Curcumin also attenuated the expression of TGF‐β1, CTGF, osteopontin, p300 and ECM proteins such as fibronectin and type IV collagen. The high‐glucose‐induced expression of VEGF and its receptor VEGF receptor II (flk‐1) was also ameliorated by curcumin. Conclusion : These results prove that curcumin produces dual blockade of both PKC‐α and PKC‐β1 activities, which suggests that curcumin is a potential adjuvant therapy for the prevention and treatment of diabetic nephropathy.  相似文献   
47.
Biocide free and biocide loaded Zeolite epoxy coatings were formulated and covalently linked to diglycidyl ether bisphenol-A type epoxy resin which acts as a base material. These formulations were applied over the zinc phosphated mild steel specimens by a brushing method to give a thickness of 200 ± 10 μm. The effect of biocide on the corrosion and fouling resistance properties were evaluated by Thermo Gravimetric Analysis (TGA), polarization, electrochemical impedance and antifouling testing. The experimental evidence reveals that the linkage of biocide loaded Nano Zeolite has tremendous potential in resisting corrosion and fouling which is ideally required for marine environments and quite superior to the biocide free Zeolite coating. The purity and the structure of these coatings were examined by an FTIR spectral study.  相似文献   
48.
Emerging trends in the area of digital very large scale integration (VLSI) signal processing can lead to a reduction in the cost of the cochlear implant. Digital signal processing algorithms are repetitively used in speech processors for filtering and encoding operations. The critical paths in these algorithms limit the performance of the speech processors. These algorithms must be transformed to accommodate processors designed to be high speed and have less area and low power. This can be realized by basing the design of the auditory filter banks for the processors on digital VLSI signal processing concepts. By applying a folding algorithm to the second‐order digital gammatone filter (GTF), the number of multipliers is reduced from five to one and the number of adders is reduced from three to one, without changing the characteristics of the filter. Folded second‐order filter sections are cascaded with three similar structures to realize the eighth‐order digital GTF whose response is a close match to the human cochlea response. The silicon area is reduced from twenty to four multipliers and from twelve to four adders by using the folding architecture.  相似文献   
49.
This article addresses the issue of friction and wear characteristics of diesel engine cylinder liner–piston ring combinations under different lubricating conditions using a pin-on-disc wear tribometer. The discs were made out of actual engine cylinder liner material using a casting process. Pins were made out of top compression ring material. The tests were conducted on a pin-on-disc tribometer for wear and friction characteristics of the cylinder liner and piston ring combination with diesel-contaminated rapeseed oil–based bio-lubricant, diesel-contaminated commercial synthetic lubrication oil (SAE 20W40), biodiesel-contaminated commercial synthetic lubrication oil (SAE 20W40), and used (150 h) commercial synthetic lubrication oil (SAE 20W40). Experimental results demonstrated that the rapeseed oil–based bio-lubricant and biodiesel-contaminated synthetic lubricant exhibited better performance in terms of wear, friction, and frictional force under similar operating conditions. Thus, usage of newly formulated bio-lubricant and biodiesel in the long run may have a positive impact on engine life.  相似文献   
50.
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