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排序方式: 共有167条查询结果,搜索用时 29 毫秒
1.
Wireless Personal Communications - In this paper, a UWB–MIMO antenna with the WLAN band-notch (5.1–5.85 GHz) characteristic is offered. This antenna consists of two radiated...  相似文献   
2.
Grewia is a tropical berry rich in anthocyanins and antioxidants but highly perishable in nature. In this study, desirable composite blend of overripe Grewia (Phalsa) berries and cantaloupe was sought for conversion to acetic acid. Composition of raw macerate, and the alcoholic and acetic ferments was analysed for sugars, alcohol and acetic acid. The primary alcohol yield varied significantly (5.75–99.44%) with blend composition. Vinegar from select blend attained 4.98% acidity with 138.57 mg mL−1 of phenols and high anthocyanins retention (74.77%). Gompertz model was used to fit the growth curves of S. cerevisiae and A. aceti (R2> 0.92) during fermentation. Presence of ethyl acetate, iso-pentyl alcohols explained pleasant sweet fruity aroma of resulting vinegar. Thus, high quality functional red fruit vinegar can be obtained to prevent spoilage and utilise the functional potential of this delicate and nutritious berry.  相似文献   
3.
An ultrathin joint in a poly(methyl methacrylate) (PMMA) beam was introduced by joining the two pieces using 1,2-dichloroethane. The viscoelastic property of the interfacial region was varied using dioctylphthalate (DOP) plasticizer and flexural waves in the beam were generated by impacting the beam with a small steel ball as well as with a calibrated experimental impact hammer. The acceleration vs. time data of a given point on a beam were used to optimally separate the wave emanating from the joint and were shown to correlate with the mechanical strength of the joint. © 1996 John Wiley & Sons, Inc.  相似文献   
4.
Purwar  Vaibhav  Gupta  Rajeev  Awasthi  Himanshi  Dubey  Sarvesh 《SILICON》2022,14(15):9361-9366
Silicon - This paper investigates the performance analysis of Dielectric Pocket (DP)-Double Gate All Around (DGAA) with three different gate dielectric materials and analyzes its performance. The...  相似文献   
5.
Gupta  Vidyadhar  Awasthi  Himanshi  Kumar  Nitish  Pandey  Amit Kumar  Gupta  Abhinav 《SILICON》2022,14(6):2989-2997
Silicon - This present article interprets the analytical models of central channel potential, the threshold voltage, and subthreshold current for Graded-Doped Junctionless-Gate-All-Around...  相似文献   
6.
7.
The present investigation explores a process for the production of erucamide, utilizing microwave irradiation as the heating element for the reaction between erucic acid and gaseous ammonia liberated by urea in the presence of catalyst (di‐ammonium hydrogen ortho‐phosphate) at atmospheric pressure and high temperature. In this process, the time of reaction is very short (25 min) and the yield is also good (92%).  相似文献   
8.
An attempt was taken to synthesize two types of polyaniline (PANI) with and without solvent followed by drying in air and vacuum oven conditions resulting different morphologies. The PANIs were prepared by chemical oxidative polymerization and studied with respect to their morphological features. Scanning electron microscopy, thermogravimetric analysis, X‐ray diffractometry, Fourier transform infrared spectroscopy, and ultraviolet–visible spectroscopy techniques were used for the characterization studies. The PANI synthesized with a solvent had a mixed morphology (fibrillar and granular), whereas PANI synthesized without a solvent had only a granular morphology. The direct‐current electrical conductivities of the samples were evaluated with an electrometer. We observed that the PANIs with mixed morphology (with solvent) were more electrically conducting than those with a single morphology (without solvent). On drying in vacuo, the conductivity of PANI decreased from 3.3 × 10?2 to 0.3 × 10?2 S/cm with solvent treatment, whereas it decreased from 0.1 × 10?2 to 0.3 × 10?3 S/cm without solvent treatment. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44091.  相似文献   
9.
Managing service quality is vital to retain customer satisfaction and augment revenues for any business organization. Often it is difficult to assess service quality due to lack of quantifiable measures and limited data. In this paper, we present a hybrid approach based on SERVQUAL and fuzzy TOPSIS for evaluating service quality of urban transportation systems. The proposed approach consists of three steps. The first step involves development of a SERVQUAL based questionnaire to collect data for measuring transportation service quality. The participants provide linguistic assessments to rate the service quality criteria and the alternatives. In step 2, the linguistic ratings are combined through fuzzy TOPSIS to generate an overall performance score for each alternative. The alternative with the highest score is finally chosen. In step 3, sensitivity analysis is conducted to evaluate the influence of criteria weights on the decision making process.The strength of the proposed approach is its practical applicability and ability to provide solution under partial or lack of quantitative information. An application of the proposed approach for evaluation of service quality of metro in Montreal is provided.  相似文献   
10.
To protect the remote server from various malicious attacks, many authentication schemes have been proposed. Some schemes have to maintain a password verification table in the remote server for checking the legitimacy of the login users. To overcome potential risks of verification tables, researchers proposed remote user authentication schemes using smartcard, in which the remote server only keeps a secret key for computing the user’s passwords and does not need any verification table for verifying legal user. In 2003 Shen, Lin, and Hwang proposed a timestamp-based password authentication scheme using smartcards in which the remote server does not need to store the passwords or verification table for user authentication. Unfortunately, this scheme is vulnerable to some deadly attacks. In this paper, we analyze few attacks and finally propose an improved timestamp-based remote user authentication scheme. The modified scheme is more efficient and secure than original scheme.  相似文献   
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