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211.
Poly(vinyl chloride) (PVC)—poly(butyl methacrylate) (PBMA) blended polymer electrolytes with lithium perchlorate (LiClO4) as the complexing salts are prepared by solution casting technique. The addition of PBMA into PVC matrix is found to induce considerable changes in physical and electrical properties of the polymer electrolytes. Addition of PBMA into PVC matrix is found to increase the conductivity by two orders of magnitude (1.108 × 10?5 S cm?1) when compared with that of the pristine PVC polymer electrolyte (10?7 S cm?1). Structural, thermal, mechanical, morphological, and polymer–salt interactions are ascertained from X‐ray diffraction (XRD), thermogravimetry/differential thermal analysis (TG/DTA), mechanical analysis, scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR) respectively. A thermal stability upto 250 °C is asserted from the TG/DTA analysis. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44939. 相似文献
212.
Wireless Personal Communications - In mobile ad hoc network (MANET), the existing papers are two-level-hash technique reduces false positives however it does not verify the location and RSS... 相似文献
213.
Rai AK Srivastava N Nigam AK Kumari U Mittal S Mittal AK 《Microscopy research and technique》2012,75(7):890-897
In this study, healing of cutaneous wounds in Labeo rohita using scanning electron microscope is reported. Wound area could be divided into three regions. Immediately after infliction of wound, edges retract exposing underlying tissues in wound gap (Region I). Simultaneously, at region close to wound edge (Region II), mucous goblet cell openings are observed with copious mucous secretions. Within 1 h, Region I gets covered by mucous secretions, and epidermis at edges starts migrating. Opposing fronts gradually advance and by 4-6 h come in contact to epithelialize wound gap. Zone of contact of fronts is demarcated by epidermal ridge, which is relatively prominent at 8 h. It gradually diminishes and is not distinguished at 24 h and afterward. At 1-4 h, microridges on epithelial cell surfaces appear irregularly arranged, widely spaced, short with abrupt ends at Region I; relatively extensive at Region II; and similar to those in controls at region surrounding Region II (Region III). At 12 h and afterward, microridges appear similar to those in controls at Regions I and II. At 1-2 h, isolated swollen epithelial cells, often in process of detachment and exfoliation at surface, are observed at Regions I and II. Such cells are infrequent at 8 h and afterward. Region I covered by migrated epidermis appears trough like at 4 h to 2 days, level of which gradually rises and at Day 4, surface of epidermis appears at a level similar to that at Regions II and III. Changes have been associated with the imbalance of osmotic homeostasis due to disruption of barrier between internal and external environment of skin. 相似文献
214.
In this paper, a novel multiple slot loading technique is studied in detail for the isolation enhancement of the dual‐band MIMO antenna system. The proposed MIMO antenna design consists of the microstrip patch loaded with T‐shaped slots parallel to the non‐radiating edge of the patch. The frequency tuning could be achieved by varying the length of the T‐shape slot arm. The proposed MIMO antenna system is optimised for operation in WLAN and WiMAX applications. The isolation enhancement is achieved by providing simple multiple slots loaded in the ground plane between radiating elements. The length of the slots is λ/4 . The system is fabricated and tested using a vector network analyser and anechoic chamber. The reduction in mutual coupling up to ?29.16 dB and ?24.09 dB for the 2.4 GHz and 3.4 GHz, respectively, is achieved. The bandwidths are 62.3 MHz (3.33–3.39 GHz) and 55.5 MHz (2.37–2.42 GHz), respectively. The total gain obtained in this case is 1.8 dBi at 2.4 GHz and 1.2 dBi at 3.4 GHz, respectively. The dimensions of the proposed designed antenna are 70 mm × 60 mm × 1.6 mm. The results were also verified through mutual coupling parameters like envelope correlation coefficient (ECC) and channel capacity loss (CCL) at the desired frequencies. 相似文献
215.
This article presents a theoretical framework useful for understanding the functionality of Hypertext systems in terms of their ability to satisfy cognitive requirements for expressing concepts and their relationships. This theoretical framework is derived from a re‐interpretation of Guilford's theory of the Structure of Intellect. 相似文献
216.
Ruchira Nandasiri Erika Zago Usha Thiyam-Holländer Neason Akiva Michael Eskin 《Journal of the American Oil Chemists' Society》2021,98(7):779-794
De-oiled canola meals are sources of protein-containing flavor-active phenolic compounds. Conventional canola oil processing utilizes an excess amount of solvents and is associated with the release of high-intensity bitter flavor-active phenolic compounds, limiting the use of the canola meal. Recent advances in the extraction and isolation of the bitter favor-active phenolic compounds from canola by-products produce protein isolates, however, would benefit the industry by producing a side-stream ingredient rich in phenolics. High temperature and pressure-aided processing, namely the accelerated solvent extraction (ASE) was investigated to extract the flavor-active bitter molecules from the canola meal. The extractability of flavor-active phenolic compounds including the major sinapates, kaempferol derivatives, and other thermo-generative compounds including thomasidioc acid (TA) was evaluated. The effects of temperature, solvent extractant and concentration, and the particle size of the meal were examined on the extraction efficiency of these phenolic compounds. Extraction temperature (180°C) was the primary determinant (p < 0.05) for the attenuation of major sinapates including sinapine and sinapic acid. Both ethanol and methanol extractants at a concentration of 70% (v/v) significantly (p < 0.05) extracted the flavor-active phenolic compounds. The pressurized high temperature through optimized ASE conditions attenuated the bitter undesirable flavor-active phenolic molecules from canola meal, thereby facilitating a potential value-added phenolic-rich by-product. 相似文献
217.
218.
Effect of the presence of the antimicrobial tylosin in swine waste on anaerobic treatment 总被引:2,自引:0,他引:2
An anaerobic sequencing batch reactor (ASBR), seeded with a biomass inoculum that previously had not been exposed to the macrolide antimicrobial tylosin (mixture of Tylosin A, B, C, and D), was operated for 3 months with swine waste without Tylosin A and for 9 months with swine waste containing Tylosin A at an average concentration of 1.6 mg/L. When swine waste with tylosin was fed to the ASBR, methane production and volatile solids removal did not appear to be inhibited and a methane yield of 0.47 L methane per gram volatile solids fed to the ASBR was observed. Throughout the operating period, Tylosin A levels in ASBR biomass and effluent were below the detection limit of 0.01 mg/L. However, during the first 3 months of operation, the levels of macrolide-lincosamide-streptogramin B (MLSB)-resistant bacteria in the ASBR biomass increased substantially as determined by hybridizations with oligonucleotide probes designed to target MLSB-resistant bacteria. Since no Tylosin A was present in the swine waste during the initial 3 months, the presence of MLSB-resistant bacteria in the swine waste was likely the reason for the increase in resistance. Subsequently, the levels of MLSB-resistant bacteria in ASBR biomass stabilized with an average of 44.9% for the 9 months of operation with swine waste containing Tylosin A. The level of MLSB-resistant bacteria in the swine waste fed to the ASBR during this period averaged 18.0%. The results indicate that anaerobic treatment of a waste stream containing tylosin was effective (based on reactor performance) and that the level of resistant bacteria in the ASBR was substantially higher than in the waste stream fed to this system. 相似文献
219.
Gluconacetobacter, a bacterial cellulose (BC)-producing organism, has ability to utilise pectin and phenolic compounds. The extract of coffee cherry husk (CCH), a high pectin- and polyphenol-containing agro waste was used in the study. Production of endo- and exo-polygalacturonase, polyphenol oxidase and tannase was observed during fermentation. Co-utilisation of glucose and galacturonic acid was observed. Accumulation of rhamnose, arabinose and galactose indicated the breakdown of pectin. Among the phenolic acids, benzoic acid derivatives were found to be degraded faster than cinnamic acid derivatives. Degradation of tannic acid was more pronounced among the bound forms than free forms in the culture broth. In BC, accumulation of free tannic, gentisic and coumaric acids was observed during the 2nd week of fermentation. The present work indicates the ability of the organism to produce BC by the utilisation of agro waste like CCH. 相似文献
220.
Thermophilic Campylobacter spp. in salad vegetables in Malaysia 总被引:1,自引:0,他引:1
Chai LC Robin T Ragavan UM Gunsalam JW Bakar FA Ghazali FM Radu S Kumar MP 《International journal of food microbiology》2007,117(1):106-111
The main aim of this study was to combine the techniques of most probable number (MPN) and polymerase chain reaction (PCR) for quantifying the prevalence and numbers of Campylobacter spp. in ulam, a popular Malaysian salad dish, from a traditional wet market and two modern supermarkets in Selangor, Malaysia. A total of 309 samples of raw vegetables which are used in ulam were examined in the study. The prevalences of campylobacters in raw vegetables were, for supermarket I, Campylobacter spp., 51.9%; Campylobacter jejuni, 40.7%; and Campylobacter coli, 35.2%: for supermarket II, Campylobacter spp., 67.7%; C. jejuni, 67.7%; and C. coli, 65.7%: and for the wet market, Campylobacter spp., 29.4%; C. jejuni, 25.5%; and C. coli, 22.6%. In addition Campylobacter fetus was detected in 1.9% of raw vegetables from supermarket I. The maximum numbers of Campylobacter spp. in raw vegetables from supermarkets and the wet market were >2400 and 460 MPN/g, respectively. 相似文献