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31.
Dinesh Prasad D. R. Bhaskar A. K. Singh 《Analog Integrated Circuits and Signal Processing》2009,61(3):309-313
An universal multi input single output type multifunction biquad is proposed. The proposed configuration employs only one
current differencing transconductance amplifier as the active element, two capacitors and three resistors. The circuit realizes
all five filter functions (i.e. Low Pass, High Pass, Band Pass, Notch and All Pass) without changing the circuit topology.
The natural frequency ω0 is independently and electronically tunable. The workability of the proposed multifunction biquad has been verified using
SPICE simulation. 相似文献
32.
33.
《水动力学研究与进展(B辑)》2006,18(5):628-628
Shanghai August 15-19, 2007Organized by Chinese Society of Theoretical and Applied Mechanics (CSTAM) Shanghai Jiaotong University (SJTU)Cosponsored by Gesellschaft fuer Angewandte Mathematik und Mechanik (GAMM) Bioengineering Division (BED/ASME) Fluid Eng… 相似文献
34.
回顾了我国40年来超高压和特高压隔离开关的发展历程,对国产超高压和特高压隔离开关的水平进行了综合分析,指出了与跨国公司产品存在的差距,并总结了发展的主要经验。 相似文献
35.
36.
The dc conductivity and dielectric parameters of glassy system of a-Se70Te30−x
Sn
x
(x = 0, 2, 4, 6, 8 and 10) glasses have been investigated. Frequency and temperature dependence of dielectric constants (ε′)
and dielectric loss (ε′′) are studied in the frequency range 120–100 kHz and temperature range 300–390 K. Dielectric dispersion
is observed when Tin (Sn) is incorporated to a-Se–Te system in the entire temperature range. These results explain that the
dc conduction loss is dominated in the present system. From dc conductivity studies it is observed that the dc conductivity
and activation energy increases with increasing tin concentration in the present system. 相似文献
37.
Sushil Kumar M. A. Majeed Khan M. Zulfequar M. Husain 《Journal of Materials Science》2007,42(1):363-367
The fabrication of devices with lead salts and their alloys with detecting and lasing capabilities has been an important technological
development. The high quality polycrystalline thin films of PbTe1−x
S
x
with variable composition (0 ≤ x ≤ 1) have been deposited onto ultra clean glass substrates by vacuum evaporation technique. Optical, structural and electrical
properties of PbTe1−x
S
x
thin films have been examined. Absorption coefficient and band gap of the films were determined by absorbance measurements
in wavelength range 2,500–5,000 nm using FTIR spectrophotometer. Sample nature, crystal structure and lattice parameter of
the films were determined from X-ray diffraction patterns. DC conductivity and activation energy of the films were measured
in temperature range 300–380 K through I–V measurements. 相似文献
38.
《Microelectronic Engineering》2007,84(5-8):885-890
Typically, the Step and Flash Imprint Lithography (S-FILTM) process uses field-to-field drop dispensing of UV-curable liquids for step-and-repeat patterning. Several applications, including patterned magnetic media, photonic crystals, and wire grid polarizers, are better served by a process that allows high-throughput, full-wafer patterning of sub-100 nm structures with modest alignment. Full-wafer imprinting requires a full-wafer template; however, creation of a wafer-scale imprint template with sub-100 nm structures is not feasible with direct-writing approaches. This paper describes a practical methodology for creating wafer-scale templates suitable for full-wafer imprinting of sub-100 nm structures.The wafer-scale template is replicated from a smaller area master template using the S-FIL step-and-repeat process. The pattern is repeated to accommodate the wafer substrate targeted for a particular application. The tone of the master template is maintained by employing an SFIL/RTM (reverse tone) pattern transfer process. To create the replicate template, the patterns are imprinted onto a fused silica wafer that has been coated with chromium and an organic transfer layer. A silicon-containing resist, SilspinTM, is spun on to planarize the organic monomer material. Following an etch back of the Silspin, the monomer and transfer layer are patterned using the Silspin as a hard mask. The Silspin and monomer stack then serves as a masking layer for the chromium and fused silica etches. The remaining monomer and chromium are then removed to create a conformal replicate template. 相似文献
39.
Siddhartha Suveda Aarya Kapil Dev Mohd Shakir Bashir Ahmed M. A. Wahab 《应用聚合物科学杂志》2012,125(5):3575-3581
The structural, optical, and morphological properties of Co60 γ irradiation on poly(ethylene terephthalate) polymer samples were studied with X-ray diffraction (XRD), ultraviolet–visible spectroscopy, scanning electron microscopy (SEM), and Raman spectroscopy. The diffraction pattern of virgin sample showed that the polymer was semicrystalline in nature. However, because of irradiation, the crystallinity decreased up to a dose level of 110 kGy and increased up to 300 kGy. The crystallite size, strain, and dislocation were calculated from the XRD data, and the crystallite size decreased from 291.07 to 346.90 Å. The absorption edge shifted from 315 to 330 nm, and the band gap of the samples decreased from 3.79 to 3.66 eV. The SEM micrographs showed radial bulging along with inhomogeneous liner exfoliation, and also, a rocky shape pattern with different sizes was observed. A significant change was found in the Raman spectra of the γ-irradiated polymer at the highest dose. The results of the structural, optical, and morphological studies show recovery characteristics at the highest dose level of 300 kGy. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
40.
Fehmida Naqvi Abdul Rauf M. M. Siddiqui M. S. Ahmad Jr. S. M. Osman 《Journal of the American Oil Chemists' Society》1997,74(6):713-717
Pseudohalogenation of methyl 9-hydroxy-cis-12-octadecenoate (I) and methyl 12-hydroxy-cis-9-octadecenoate (II) has been carried out with N,N-dibromobenzenesulfonamide (NNDBS). Compounds I and II, on reaction with NNDBS, formed four and three products, respectively. The interesting feature of these reactions was the
formation of 1,4-epoxy compounds. The structures of individual compounds were established with the help of elemental and spectral
analysis. 相似文献