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排序方式: 共有198条查询结果,搜索用时 15 毫秒
1.
Silicon - The promising capability of Triple Material Surrounding Gate Junctionless Tunnel FET (TMSG – JL – TFET) based 6 T SRAM structure is demonstrated by employing... 相似文献
2.
Tolerance specification is an important part of mechanical design. Design tolerances strongly influence the functional performance and manufacturing cost of a mechanical product. Tighter tolerances normally produce superior components, better performing mechanical systems and good assemblability with assured exchangeability at the assembly line. However, unnecessarily tight tolerances lead to excessive manufacturing costs for a given application. The balancing of performance and manufacturing cost through identification of optimal design tolerances is a major concern in modern design. Traditionally, design tolerances are specified based on the designer’s experience. Computer-aided (or software-based) tolerance synthesis and alternative manufacturing process selection programs allow a designer to verify the relations between all design tolerances to produce a consistent and feasible design. In this paper, a general new methodology using intelligent algorithms viz., Elitist Non-dominated Sorting Genetic Algorithm (NSGA-II) and Multi Objective Particle Swarm Optimization (MOPSO) for simultaneous optimal selection of design and manufacturing tolerances with alternative manufacturing process selection is presented. The problem has a multi-criterion character in which 3 objective functions, 3 constraints and 5 variables are considered. The average fitness factor method and normalized weighted objective functions method are separately used to select the best optimal solution from Pareto optimal fronts. Two multi-objective performance measures namely solution spread measure and ratio of non-dominated individuals are used to evaluate the strength of Pareto optimal fronts. Two more multi-objective performance measures namely optimiser overhead and algorithm effort are used to find the computational effort of NSGA-II and MOPSO algorithms. The Pareto optimal fronts and results obtained from various techniques are compared and analysed. 相似文献
3.
Balamurugan A Benhayoune H Kannan S Laquerriere P Michel J Balossier G Ferreira JM 《Microscopy research and technique》2008,71(9):684-688
The present study deals with the short-term physicochemical reactions at the interface between bioactive glass particles [55SiO(2)-20CaO-9P(2)O(5)-12Na(2)O-4MgO. mol%] and biological fluid (Dulbecco Modified Eagle's Medium (DMEM)). The physicochemical reactions within the interface are characterized by scanning transmission electron microscopy (TEM) (STEM) associated with Energy-dispersive X-ray spectroscopy (EDXS). Microanalysis of diffusible ions such as sodium, potassium, or oxygen requires a special care. In the present investigation the cryo-technique was adopted as a suitable tool for the specimen preparation and characterization. Cryosectioning is essential for preserving the native distribution of ions so that meaningful information about the local concentrations can be obtained by elemental microanalysis. The bioglass particles immersed in biological fluid for 24 h revealed five reaction stages: (i) dealkalization of the surface by cationic exchange (Na(+), Ca(2+) with H(+) or H(3)O(+)); (ii) loss of soluble silica in the form of Si(OH)(4) to the solution resulting from the breakdown of Si--O--Si bonds (iii); repolymerization of Si(OH)(4) leading to condensation of SiO(2)); (iv) migration of Ca(2+) and PO(4) (3-) to the surface through the SiO(2)-rich layer to form CaO-P(2)O(5) film; (v) crystallization of the amorphous CaO-P(2)O(5) by incorporating OH-- or CO(3) (2-) anions with the formation of three different surface layers on the bioactive glass periphery. The thickness of each layer is approximately 300 nm and from the inner part to the periphery they consist of Si--OH, which permits the diffusion of Ca(2+) and PO(4) (3-) ions and the formation of the middle Ca--P layer, and finally the outer layer composed of Na--O, which acts as an ion exchange layer between Na(+) ions and H(+) or H(3)O(+) from the solution. 相似文献
4.
A series of polymethacrylates containing triazole ring linked chalcone were designed and synthesized. These conjugated chalcone polymers are modulate under the light depending on the pendant substituents (–N(CH3)2, CH3, OCH3, Br, H & NO2). The steady-state absorption and emission spectroscopic techniques have been used to investigate intramolecular charge transfer (ICT) behaviour of the polymers. Absorption spectra in different organic solvents demonstrate the presence of ICT in polymer 5a. On the other hand, its excited singlet state exhibits high ICT characters as manifested by polarity of solvents. Interestingly, ICT emission maximum is strongly red shifted (53 nm). The emission intensities of fluorophore are compared with those measured after crosslinking, suggesting that the statically quenched fluorophores are entirely non-emissive. The emission decay of polymer 5a displays bi-exponentially with life time of 0.52 and 1.62 ns ascribed to presence of locally excited ICT state. Cyclic voltammogram demonstrates irreversible oxidation potential at 0.9 V indicates formation mono-radical cation. 相似文献
5.
Adhesive‐coated glass fibers (3 and 6 mm in length) were added at loadings of 10, 20, and 30 phr in natural rubber (NR), nitrile rubber (NBR), and ethylene–propylene–diene comonomer (EPDM) formulations in both plain and carbon black mixes. The compounds were mixed in a two‐roll mill and were characterized for their cure properties, tensile, tear, and Mullin's effect. In NR mixes, all of the formulations showed reversion in cure behavior, suggesting that NR remained unaffected. In NBR and EPDM mixes, almost all of the mechanical properties of the fiber improved. The result was more significant in EPDM than in NBR. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1111–1123, 2004 相似文献
6.
A 2D analytical model for transconductance, Sub-threshold current and Sub-threshold swing for Triple Material Surrounding Gate MOSFET (TMSG) is presented in this paper. Based on the solution of two dimensional Poisson equation, the physics based model of sub-threshold current of the device is derived. The model also includes the effect of gate oxide thickness and silicon thickness on the sub-threshold swing characteristics. Transconductance to drain current ratio of the triple material surrounding gate is calculated since it is a better criterion to access the performance of the device. The effectiveness of TMSG design was scrutinized by comparing with other triple material and dual material gate structures. Moreover the effect of technology parameter variations is also studied and proposed. This proposed model offers basic guidance for design of TMSG MOSFETs. The results of the analytical model are compared with the MEDICI simulation results thus providing validity of the proposed model. 相似文献
7.
We report synthesis and magnetization of MSr2Y1.5Ce0.5Cu2O10 (M/Y-1222) compounds with M = Ru, Mn and Cr by HPHT. They are synthesized at high-pressure of 6 GPa in optimized temperatures of up to 1450 °C, for Ru, Mn and 1550 °C in the case of Cr based Y/1222, for a time duration of three hours for all the samples. All the samples crystallized with tetragonal structure in I4/mmm space group. Few minor impurities are also seen in the case of Mn,Cr/Y-1222 samples. DC magnetic susceptibility measurements exhibited ferromagnetic like transition for all the three compounds at low temperatures. At 5 K, the magnetization M(H) experiments showed clear ferromagnetic like hysteresis loops for Ru and Mn samples with sizeable returning moment (Mr) and coercive field (Hc). In the case of Cr/Y-1222 system though, ferromagnetism is visible below around 45 K in susceptibility measurements, the characteristic Mr and Hc are not seen. To the best of our knowledge the Mn,Cr/Y-1222 phases are synthesized for the first time and the quality of our earlier reported Ru/Y-1222 is improved. 相似文献
8.
C. Sasikumar K. Balamurugan S. Rajendran S. Naveenkumar 《Materials and Manufacturing Processes》2016,31(6):701-706
Among all alternate fuel sources available, the biodiesel of Jatropha curcas appears to be a potential fuel as it widely exists in Asia. The Jatropha methyl ester (JME) is produced by transesterification process. In the transesterification process, alkyl group of ester exchanges with that of an alcohol. This work focuses on optimizing various parameters like quantities of methanol, KOH, and stirrer speed, which influence high JME yield. Based on L9 orthogonal array, experiments are conducted by using Taguchi technique. All the nine combinations of L9 orthogonal array are experimentally done for extraction of JME, and then it is used for analysis in Taguchi technique. The analysis of maximum yield is done on the basis of “larger is better” signal to noise ratio (S/N ratio). The best combination in the L9 orthogonal array is found to be methanol (110 ml), KOH (1.306 gm), and stirrer speed (1200 rpm). The influence of methanol, KOH, and stirrer speed on the yield is found by analysis of variance (ANOVA). Based on the results of ANOVA, it is found that the influence of methanol, KOH, and stirrer speed on the yield are obtained as 70.10%, 20.35%, and 5.78%, respectively. 相似文献
9.
Tulyaganov DU Agathopoulos S Valerio P Balamurugan A Saranti A Karakassides MA Ferreira JM 《Journal of materials science. Materials in medicine》2011,22(2):217-227
New compositions of bioactive glasses are proposed in the CaO–MgO–SiO2–Na2O–P2O5–CaF2 system. Mineralization tests with immersion of the investigated glasses in simulated body fluid (SBF) at 37°C showed that
the glasses favour the surface formation of hydroxyapatite (HA) from the early stages of the experiments. In the case of daily
renewable SBF, monetite (CaHPO4) formation competed with the formation of HA. The influence of structural features of the glasses on their mineralization
(bioactivity) performance is discussed. Preliminary in vitro experiments with osteoblasts’ cell-cultures showed that the glasses
are biocompatible and there is no evidence of toxicity. Sintering and devitrification studies of glass powder compacts were
also performed. Glass-ceramics with attractive properties were obtained after heat treatment of the glasses at relatively
low temperatures (up to 850°C). 相似文献
10.
Dr. Balamurugan Dhayalan Dr. Ann Fitzpatrick Dr. Kalyaneswar Mandal Dr. Jonathan Whittaker Prof. Dr. Michael A. Weiss Prof. Dr. Andrei Tokmakoff Prof. Dr. Stephen B. H. Kent 《Chembiochem : a European journal of chemical biology》2016,17(5):415-420
Isotope‐edited two‐dimensional Fourier transform infrared spectroscopy (2 D FTIR) can potentially provide a unique probe of protein structure and dynamics. However, general methods for the site‐specific incorporation of stable 13C=18O labels into the polypeptide backbone of the protein molecule have not yet been established. Here we describe, as a prototype for the incorporation of specific arrays of isotope labels, the total chemical synthesis—via a key ester insulin intermediate—of 97 % enriched [(1‐13C=18O)PheB24] human insulin: stable‐isotope labeled at a single backbone amide carbonyl. The amino acid sequence as well as the positions of the disulfide bonds and the correctly folded structure were unambiguously confirmed by the X‐ray crystal structure of the synthetic protein molecule. In vitro assays of the isotope labeled [(1‐13C=18O)PheB24] human insulin showed that it had full insulin receptor binding activity. Linear and 2 D IR spectra revealed a distinct red‐shifted amide I carbonyl band peak at 1595 cm?1 resulting from the (1‐13C=18O)PheB24 backbone label. This work illustrates the utility of chemical synthesis to enable the application of advanced physical methods for the elucidation of the molecular basis of protein function. 相似文献