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51.
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Crack free calcium modified PZT composite films have been synthesized using modified sol-gel process by depositing the slurries prepared by mixing powder of composition PbZr0.52Ti0.48O3 and sol of composition Pb(1−x)CaxZr0.52Ti0.48O3 (where x = 0, 0.06, 0.1) on Pt(1 1 1)/Ti/SiO2/Si substrate. The infilteration process has also been employed which resulted in dense microstructure of the films. Thickness of the films as measured by SEM of cross section of the films was more than 25 μm. The XRD patterns of the resultant films consisted of pure perovskite phase and no peak related to either pyrochlore phase or Pt substrate was observed. The room temperature dielectric constant and loss were compared. The temperature dependence of dielectric constant revealed that TC of all the films was same, i.e., 351 °C, in spite of different compositions of the sol used. Well saturated PE-loops of the films show that the films were ferroelectric in nature. 相似文献
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The future generation of wireless communications systems uses the generalized frequency division multiplexing (GFDM) due to its viable candidate waveform to perform multiple user scheduling. It is a non-orthogonal waveform susceptible to intercarrier and intersymbol interference (ISI); still, it offers flexible pulse shaping that enhances the efficiency of user scheduling. Here, to accomplish spatial diversity, the multiple-input multiple-output (MIMO) is incorporated with GFDM to enhance the performance; there is also an extra inter-antenna interference problem that limits the model's performance. The issue concerning inter-antenna interference can be resolved by adopting pilot-based information transfer. The detection of a signal at the receiver based on the minimum mean square error has the issue of computational complexity while enhancing the estimation quality of a detector. Hence, a low-complexity channel estimation technique is proposed in this research using the V-degree polynomial-based channel estimation technique, wherein the cubic order computation is reduced to square order. Also, the proposed adaptive pulse shaping technique, wherein the filter coefficient is optimized using the gazelle optimization algorithm (GOA) to provide optimal pulse shaping filter parameters by employing bit error rate (BER) as the objective function. The performance of a proposed V-degree polynomial-based channel estimation is analyzed based on various assessment measures like BER and MSE and acquired the minimal values of 5.75E-05 and 2.07E-05, respectively. 相似文献
55.
Effect of Novel Starter Culture on Reduction of Biogenic Amines,Quality Improvement,and Sensory Properties of Doenjang,a Traditional Korean Soybean Fermented Sauce Variety 下载免费PDF全文
Shruti Shukla Jong Suk Lee Hae‐Kyong Park Jung‐Ah Yoo Sung‐Yong Hong Jong‐Kyu Kim Myunghee Kim 《Journal of food science》2015,80(8):M1794-M1803
To select appropriate microorganisms as starter cultures for the reliable and reproducible fermentation of soybean fermented products of Korean Doenjang, various ratios of fungi (Aspergillus oryzae J, Mucor racemosus 15, M. racemosus 42) combined with Bacillus subtilis TKSP 24 were selected as either single, double, or multiple Meju strains for commercial mass production of Doenjang, followed by analysis of sensory characteristics. In the sensory evaluation, Doenjang BAM15‐1 and BAM42‐1, which were fermented with multiple strains (1:1:1), showed the highest sensory scores as compared to control. Based on sensory characteristics, 6 Doenjang samples were subjected to quantitative determination of amino acids, free sugars, and organic acids (volatile and nonvolatile) contents, followed by determination of biogenic amines. Total sweet taste amino acid contents were highest in BAM15‐1 and BAM42‐1 samples (333.7 and 295.8 mg/100 g, respectively) and similar that of control (391.1 mg/100 g). Samples BAM15‐1 and BAM42‐1 showed the relatively high volatile and nonvolatile organic acid contents (154.24, 192.26, and 71.31, 82.42 mg/100 g, respectively). In addition, BAM15‐1 and BAM42‐1 showed negligible biogenic amine formation, ranging from 0.00 to 1.02 and 0.00 to 3.92 mg/100 g, respectively. These findings indicate that determination of food components along with sensory and quality attributes using multiple microbial Meju strains as a starter culture may provide substantial results on improved quality fermented Doenjang products. 相似文献
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Megan Quedley Brendan Ng Nikhil Sapre Matthew Blakiston Alexandra Crawford Rosanne Devadas Hamish McLaren Shruti Anand Mahu Tipu Viswas Dayal Singithi Chandrasiri George Thomson Richard Edwards 《Nicotine & tobacco research》2008,10(8):1347-1354
We investigated retailer compliance with point-of-sale display legislation, using a New Zealand region as a case study. An observational survey was conducted of nonspecialist tobacco retailers in the lower North Island of New Zealand during 2006. Compliance was assessed in relation to store type (dairies, convenience stores, supermarkets, and service stations) and by characteristics of the population of the census area unit in which the store was situated. These characteristics include the level of socioeconomic deprivation and proportions of Maori (indigenous New Zealanders), Pacific Islanders, and children aged less than 19 years. Out of the 288 stores surveyed, 185 (64%) had at least one breach of the point-of-sale regulations. The most common breaches were a failure to display a "Smoking Kills" sign, visibility of tobacco from outside the premises, and displaying tobacco less than 1 m from children's products. Compliance was significantly worse in dairies (small local general stores) and convenience stores. Stores situated in areas in the top quartile for the proportion of children were much more likely to have high levels of noncompliance (> or =3 breaches) and to display tobacco products close to children's products. This study is one of very few to systematically investigate retailer compliance with point-of-sale display regulations for tobacco products. The results suggest that the implementation of legislation to partly limit retail displays of tobacco products can be difficult. A ban on retail displays of tobacco products is likely to be a more effective and enforceable policy. 相似文献
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Small, portable electronic devices need power supplies that have long life, high energy efficiency, high energy density, and can deliver short power bursts. Hybrid power sources that combine a high energy density fuel cell, or an energy scavenging device, with a high power secondary battery are of interest in sensors and wireless devices. However, fuel cells with low self-discharge have low power density and have a poor response to transient loads. A low capacity secondary lithium ion cell can provide short burst power needed in a hybrid fuel cell–battery power supply. This paper describes the polarization, cycling, and self-discharge of commercial lithium ion batteries as they would be used in the small, hybrid power source. The performance of 10 Li-ion variations, including organic electrolytes with LixV2O5 and LixMn2O4 cathodes and LiPON electrolyte with a LiCoO2 cathode was evaluated. Electrochemical characterization shows that the vanadium oxide cathode cells perform better than their manganese oxide counterparts in every category. The vanadium oxide cells also show better cycling performance under shallow discharge conditions than LiPON cells at a given current. However, the LiPON cells show significantly lower energy loss due to polarization and self-discharge losses than the vanadium and manganese cells with organic electrolytes. 相似文献
59.
The paper aims to model the flexibility of a dovetail joint encountered in machine-tool structures. The investigation is concerned with the determination of a flexibility matrix through an approximate semianalytical procedure using finite element analysis. The contact region and the pressure distribution on the two mating surfaces are assumed. The deformation pattern of the male and female parts are separately analysed and from compatibility and equilibrium considerations, the overall deformation pattern of the joint is calculated for the three out of plane external force/moment components. The joint flexibility is represented by a 3 × 3 flexibility matrix. Results are presented for the knee-column joint and the column-overarm joint of a milling machine structure. 相似文献
60.
T. L. Sterrett R. Sachdeva P. Jerabek 《Journal of materials science. Materials in medicine》1992,3(6):402-407
The effect of various plasma surface treatments on the protein adsorption characteristics of two polyurethane elastomers (Acushnet E417-0 [ACx] and Texin 480 AR [TN]) were studied. Both substrates are based upon diphenylmethane 4,4-diisocyanate (MDI) hard segments and polyester soft segments. Adsorption characteristics of the untreated samples were initially established, followed by plasma treated surfaces. Contact angle and 2 h albumin adsorption were determined. (1) Results of this study indicate that the protein adsorption characteristics of crosslinked substrate ACx is more linear than that of non-crosslinked substrate TN. Further, substrate TN adsorbs seven-fold greater protein at a rate four times higher on its surface than ACx.N,N-Ethylene bis (stearamide), a processing aid used in substrate TN, may encourage greater protein adsorption on substrate TN and variation in the soft segment mobility between the substrates also may affect their adsorption characteristics. (2) Plasma treatments using CH4 and/or C
x
F
y
chemistries increased the contact angle for both substrates while those with O2 and O2/CF4 decreased the contact angle for the substrates considered. In general, the contact angle of the substrates exhibiting greater protein adsorption was smaller. 相似文献