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431.
Sheng-Lyang Jang Cheng-Hsin Liu Miin-Horng Juang 《International Journal of Electronics》2013,100(4):521-527
A low-voltage wide locking range injection-locked frequency divider (ILFD) using a standard 0.18?µm complementary metal-oxide-semiconductor process is presented. The ILFD is based on a differential LC VCO with one injection metal oxide semiconductor field effect transistor (MOSFET) for coupling external signals to the resonator. The low-voltage operation and wide locking range is obtained by boosting the gate voltage swing of the ILFD. Measurements show that at the supply voltage of 0.67?V, the divider's free-running frequency is tunable from 3.91 to 4.22?GHz, and the core power consumption is 1.87?mW. At the incident power of 0?dBm the divide-by-4 operation range is about 2?GHz (12.3%), from the incident frequency 15.3–17.3?GHz. The divide-by-2 locking range is about 5.1?GHz (77%), from the incident frequency 4.1–9.2?GHz. 相似文献
432.
Hsun-Lien Lin Huey-Ling Chang Tzong-Yuan Juang Rong-Ho Lee Shenghong A. Dai Ying-Ling Liu Ru-Jong Jeng 《Dyes and Pigments》2009,82(1):76-83
Poly(N-acylurea)–clay nanocomposites consisting of a modified montmorillonite and poly(N-acylurea) were prepared from which poly(amide-imide)–clay nanocomposites were subsequently obtained via the sequential self-repetitive reaction of poly(N-acylurea). The moderate Tg of poly(N-acylurea) allows the nonlinear optically active polymer to exhibit high poling efficiency; in situ poling and curing increased the Tgs of poly(amide-imide)–clay nanocomposites. Electro-optical coefficients, r33 of ~17–20 pm/V (830 nm), were achieved; high temporal stability (120 °C) and waveguide optical losses of 3.4–3.9 dB/cm at 1310 nm were also obtained for poly(amide-imide)–clay nanocomposites. 相似文献
433.
Ching Hsuan Lin Jui Chun Chen Chu Ming Huang Jih Mirn Jehng Hou Chien Chang Tzong Yuan Juang Wen Chiung Su 《Polymer》2013
We prepared a side-chain phenol-functionalized poly(ether sulfone) (P1) from a one-pot reaction of a 4,4′-dihydroxybenzophenone (DHBP)-based poly(ether sulfone), poly(oxy-1,4-phenylenecarbonyl-1,4-phenyleneoxy-1,4-phenylene-sulfonyl-1,4-phenylene (DHBP-PES)), with 9,10-dihydro-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and phenol in the presence of sulphuric acid. The phenol linkages of P1 act as reacting sites for epoxy resins. Subsequently, flexible and light-yellow transparent films of epoxy thermosets can be achieved from the curing of P1 with cresol novolac epoxy (CNE) and diglycidyl ether of bisphenol A (DGEBA). The thermoset based on P1 and CNE (P1/CNE) shows a high Tg value (241 °C), a low coefficient of thermal expansion (44 ppm/°C), and flame retardancy (VTM-0). The moderate-to-high molecular weight of P1 is responsible for the characteristics high Tg and flexibility, which are rarely seen in epoxy thermosets based on a low-molecular weight curing agent. 相似文献
434.
Yu-Chuan Juang Duu-Jong Lee Juin-Yih Lai 《Journal of the Chinese Institute of Chemical Engineers》2008,39(6):657-661
Aerobic granulation (AG) and membrane bioreactor (MBR) are two promising, novel environmental biotechnological processes that draw interest of researchers engaging work in the area of biological wastewater treatment. Membrane fouling in the combined, AGMBR process was investigated in this work. The fouling layer formed on hollow-fibre membranes in both reactors were for the first time directly observed with the multiple staining and confocal laser scanning microscope (CLSM) technique. Fouling layers in both reactors presented a rather heterogeneous fouling layer, with that on SMBR much more redundant than that on AGMBR. The EPS in the AGMBR fouling layer was principally consisted of proteins, α-polysaccharides, and lipids, with few β-polysaccharides or cells. In SMBR, large quantity of DNA was probed in the fouling layer. Over-deposition of fouling layer on hollow-fibre membrane may assist preventing occurrence of irreversible fouling, which is beneficial to long-term operation of the AGMBR. 相似文献
435.
Characteristics of Elovich equation used for the analysis of adsorption kinetics in dye-chitosan systems 总被引:2,自引:0,他引:2
Feng-Chin Wu Ru-Ling Tseng Ruey-Shin Juang 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2009,150(2-3):366-373
The Elovich equation has been widely used in adsorption kinetics, which describes chemical adsorption (chemical reaction) mechanism in nature. The approaching equilibrium parameter of Elovich equation (RE) was used here to describe the characteristic curves of adsorption kinetics. Of 64 adsorption systems surveyed in this work, 80% of the RE values were between 0.1 and 0.3 with an adsorption curve belonging to “mild rising”. The results of three examples revealed that the characteristic curve of Elovich equation was between those of Lagergren's first-order equation and intraparticle diffusion model. Chitosans prepared from prawn, lobster, and crab shells were used for the adsorption of a reactive dye. The mean deviation obtained from the three kinetic models revealed that Elovich equation was the most suitable one. All the adsorption systems were in the “mild rising” zone. The RE value was related to the type of raw material but not to the particle size of chitosan, which agreed with chemical adsorption nature of the Elovich equation. According to an optimal adsorbent consumption of 85% coupled with its corresponding operating time (t0.85) proposed, these two parameters could be used for engineering design. 相似文献