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Scientometrics - The article published on 5 July 2021 is well-written and of interest. However, some improvements could be made, such as ten Tables/Figures can be shortened to highlight the focused... 相似文献
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Yu Wang He Zhang Shuqiang Jiao Kuo-Chih Chou Guo-Hua Zhang 《Journal of the American Ceramic Society》2020,103(4):2399-2406
Molybdenum boride is an ideal hard and wear-resistant material. In this study, a new method is proposed for preparing molybdenum boride, by which Mo first reacts with B4C to generate the mixture of molybdenum boride and C, and then the product is decarburized by molten Ca to generate CaC2. Pure molybdenum boride could be obtained after acid leaching to remove the by-product CaC2. According to the experimental and thermodynamic calculation results, it is concluded that the single-phase MoB could be successfully prepared, while Mo2B, Mo2B5, and MoB4 could not be synthesized by this method. Moreover, it was found that the particle size of finally prepared MoB is determined by particle size of raw Mo powder. The residual carbon content of the product could be decreased to 0.10 wt% after first reaction at 1673 K for 6 hours and then decarburization reaction at 1673 K for 6 hours. 相似文献
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Koay Seong Chun Chan Ming Yeng Chou Pui May Tshai Kim Yeow Ong Thai Kiat Cheah Kean How 《乙烯基与添加剂工艺杂志》2020,26(1):10-16
Chrysanthemum flower is among one of the highly sought after and widely planted flower crops, in particular for cultural and religious ceremonies. However, the chrysanthemum stem and stalk have little value and usually discard as by‐product waste from floristry. The objective of this research is to investigate the potential value of utilizing chrysanthemum stem and stalk as reinforcing fillers for thermoplastic composites. In this study, 2‐mm thick composite sheet containing predefined formulations of polylactic acid (PLA), chrysanthemum waste filler (CWF) ranging from 15 to 60 phr, and maleated polyethylene (MAPE) coupling agent up to 5 phr were prepared with the aid of Haake internal mixer and compression molding. The effect of MAPE loading on tensile, thermal, and morphological properties of PLA/CWF composites was investigated. The findings revealed that PLA/CWF composite attained improved tensile modulus compared to the neat PLA, and the tensile modulus increases with higher concentration of CWF. However, both tensile strength and elongation at break reduces with increase loading of CWF. Overall, PLA/CWF composites with MAPE shows better performance compared to those without MAPE, where an optimum strength of 21.8 MPa can be achieved with 60 phr CW and 3 phr MAPE. The measured tensile strength is comparable to alternatives natural fiber thermoplastic composites demonstrating its potential to be used in non‐structurally demanding application. J. VINYL ADDIT. TECHNOL., 26:10–16, 2020. © 2019 Society of Plastics Engineers 相似文献
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Chou Y.C. Leung D. Lai R. Grundbacher R. Barsky M. Kan Q. Tsai R. Wojtowicz M. Eng D. Tran L. Block T. Liu P.H. Nishimoto M. Oki A. 《Electron Device Letters, IEEE》2003,24(6):378-380
The authors have investigated the reliability performance of G-band (183 GHz) monolithic microwave integrated circuit (MMIC) amplifiers fabricated using 0.07-/spl mu/m T-gate InGaAs-InAlAs-InP HEMTs with pseudomorphic In/sub 0.75/Ga/sub 0.25/As channel on 3-in wafers. Life test was performed at two temperatures (T/sub 1/ = 200 /spl deg/C and T/sub 2/ = 215 /spl deg/C), and the amplifiers were stressed at V/sub ds/ of 1 V and I/sub ds/ of 250 mA/mm in a N/sub 2/ ambient. The activation energy is as high as 1.7 eV, achieving a projected median-time-to-failure (MTTF) /spl ap/ 2 /spl times/ 10/sup 6/ h at a junction temperature of 125 /spl deg/C. MTTF was determined by 2-temperature constant current stress using /spl Delta/G/sub mp/ = -20% as the failure criteria. The difference of reliability performance between 0.07-/spl mu/m InGaAs-InAlAs-InP HEMT MMICs with pseudomorphic In/sub 0.75/Ga/sub 0.25/As channel and 0.1-/spl mu/m InGaAs-InAlAs-InP HEMT MMICs with In/sub 0.6/Ga/sub 0.4/As channel is also discussed. The achieved high-reliability result demonstrates a robust 0.07-/spl mu/m pseudomorphic InGaAs-InAlAs-InP HEMT MMICs production technology for G-band applications. 相似文献
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BACKGROUND: The enterococci have become important nosocomial pathogens. They can cause multiple site infections and enterococcal bacteremia becomes more frequently associated with a high mortality rate. Previous studies of enterococcal bacteremia showed a variety of results. To establish the significance and importance of enterococci as nosocomial pathogens in this hospital, to characterize their clinical pictures and to search for the risk factors for mortality, this retrospective study was performed. METHODS: There were 208 cases of enterococcal bacteremia which occurred from 1988 to 1992. Twenty-seven cases had no medical charts, dismissing possibility of evaluation. Finally, 181 cases of enterococcal bacteremia were analysed. RESULTS: One hundred and eighteen episodes were nosocomial infections. Polymicrobial bacteremia occurred in 68.5% of the patients and the most common co-isolate was Pseudomonas aeruginosa. Those patients (78.5%) with underlying diseases and malignancies were the most common underlying problems. The portal of entry could be found in 69.6 percent of patients, with the gastrointestinal tract the most common sources. Antimicrobial susceptibility testing showed high gentamicin resistance rate (89.5%), and ampicillin still had about 80 percent sensitivity rate. The group who received specific antibiotic therapy for enterococcus showed lower mortality (36.4% versus 47.6%). Only one case had infective endocarditis. Forty-nine patients suffered from septic shock, the cause of 30 deaths. Totally 75 patients died during hospitalization. Besides sepsis, another major cause of death was their underlying diseases itself. CONCLUSIONS: Enterococci have no doubt become important nosocomial pathogens and enterococcal bacteremia were associated with high mortality, especially in elderly patients with underlying diseases such as malignancy or diabetes. When clinically dealing with sepsis from the gastrointestinal or biliary tract, especially when previous cephalosporins therapy showed no response, the possibility of enterococcal bacteremia should always be considered. 相似文献
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Tsern-Huei Lee Jin-Jye Chou 《Parallel and Distributed Systems, IEEE Transactions on》1994,5(11):1206-1210
The banyan network, and networks topologically equivalent to it, have recently been adopted as interconnection networks in multiprocessor systems. Often, a multiprocessor system is reconfigured when the banyan network becomes faulty. It is possible to avoid a complicated reconfiguration process as long as the faulty banyan network still possesses the dynamic full access (DFA) property. In this paper, we determine a necessary and sufficient condition for a faulty banyan network to possess the DFA property and design a test procedure based on the condition. The test procedure can be used to decompose a faulty banyan network into subsystems possessing the DFA property. We also evaluate the probability that a banyan network loses the DFA property, given the number of faulty switching elements. It is found that as long as faults do not occur in switching elements located in the first and last stages, this probability is very small, even when there are quite a few faulty switching elements 相似文献