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71.
This paper describes a 2.5-3.125-Gb/s quad transceiver with second-order analog delay-locked loop (DLL)-based clock and data recovery (CDR) circuits. A phase-locked loop (PLL) is shared between receive (RX) and transmit (TX) chains. On each RX channel, an amplifier with user-programmable input equalization precedes the CDR. Retimed data then goes to an 1:8/1:10 deserializer. On the TX side, parallel data is serialized into a high-speed bitstream with an 8:1/10:1 multiplexer. The serial data is introduced off-chip through a high-speed CML buffer having single-tap pre-emphasis. Proposed DLL-based CDR can tolerate large frequency offsets with no jitter tolerance degradation due to its second-order PLL-like nature. Also, this study introduces an improved charge-pump and an improved phase-interpolator. Fabricated in a 0.15-/spl mu/m CMOS process, the 1.9-mm/sup 2/ transceiver front-end operates from a single 1.2-V supply and consumes 65-mW/channel of which 32 mW is due to the CDR. CDR jitter generation and high-frequency jitter tolerance are 5.9 ps-rms and 0.5 UI, respectively, for 3.125 Gb/s, 2/sup 23/-1 PRBS input data with 800-ppm frequency offset. 相似文献
72.
Paap Kenneth R.; Johansen Linda S.; Chun Elvin; Vonnahme Paul 《Canadian Metallurgical Quarterly》2000,26(6):1691
Three experiments using the Reicher task show that performance on low-frequency words is disrupted if the incorrect alternative forms a higher frequency word. This neighborhood frequency effect occurs for both energy and pattern masks and for different sets of items. When the upcoming word is primed and its accessibility is enhanced, the neighborhood frequency effect is eliminated. Experiments 4a and 4b tested the neighborhood frequency effect using a same–different task and a signal-detection analysis. Neighborhood frequency affected the decision criterion but not the sensitivity of the perceptual system. Experiment 5 showed that many words with a frequency in the range from 1 to 5 per million are not recognized out of context. These results are consistent with the hypothesis that frequency effects in the Reicher task are caused by a bias in the decision system and can be simulated with the stochastic activation–verification model. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
74.
Robert L. Kirkpatrick John H. Brower Elvin W. Tilton 《Journal of Stored Products Research》1973,9(1):19-23
Samples of soft winter wheat containing eggs, larvae, pupae, or adults of Rhyzopertha dominica (F.) were given one of the following treatments: (1) Gamma radiation; (2) infra-red radiation; (3) microwave radiation; (4) gamma + infra-red; or (5) gamma + microwave. The percentage of adult emergence from treated immatures or the mortality and fecundity of treated adults provided a basis for evaluating the effectiveness of the treatments.The average reductions in emergence were 54, 55, and 42 per cent for gamma, infra-red, and microwave treatments, respectively. The reductions in emergence averaged 99 per cent for the gamma + infra-red combination and 96 per cent for the gamma + microwave combination. These mortalities were about 20 per cent higher than predicted. Adult mortality data were inconclusive because of the very low gamma dosage used. However, reductions in adult fecundity for the above combinations were about 95 and 89 per cent, respectively. These were about 22 and 9 per cent greater than the predicted reductions in fecundity. 相似文献
75.
When male rats were given either a single dose of cadmium (3.58 mg CdCl2.6H2O/kg, i.p.) 72 h prior to sacrifice or a single dose of nickel (59.5 mg NiCl2.6H2O/kg, s.c.) 16 h prior to sacrifice, the activities of ethylmorphine N-demethylase, aminopyrine N-demethylase and aniline 4-hydroxylase, and the levels of cytochrome P-450 and microsomal heme were significantly decreased. Cadmium decreased the cytochrome b5 level significantly, whereas it did not alter the NADPH-cytochrome c reductase activity significantly. In contrast, Ni did not alter the cytochrome b5 level significantly but decreased the NADPH-cytochrome c reductase activity significantly. For the combined treatment, animals received the single dose of nickel 56 h after the single dose of cadmium and then they were killed 16 h later. In these animals ethylmorphine N-demethylase, aminopyrine N-demethylase and NADPH-cytochrome c reductase activities and cytochromes P-450 and b5 levels increased significantly as compared to those of controls, whereas aniline 4-hydroxylase activity and microsomal heme level remained unaltered. In concordance with the increase in the enzyme activities, certain P-450 protein bands were observed to be elevated when studied on SDS-polyacrylamide gel electrophoresis. Furthermore, when the monooxygenase activities and SDS-polyacrylamide gel electrophoresis profiles of combined metal-treated animals were compared with those of the animals treated with classic inducers such as phenobarbital (75 mg/kg i.p., 72, 48 and 24 h prior to sacrifice) and 3-methylcholanthrene (20 mg/kg i.p., 72, 48 and 24 h prior to sacrifice), the combination of metals seemed to have tendency to stimulate certain phenobarbital and 3-methylcholanthrene inducible cytochrome P-450 isozymes. 相似文献
76.
A fast exhaustive search algorithm for rate-constrained motion estimation is presented. The motion vectors are selected from a search window based on a rate-distortion criterion by successively eliminating the search positions depending on the rate constraint. The estimation performance of the proposed algorithm is identical to the performance of the rate-constrained full search algorithm, with considerable reduction in computation. Simulation results indicate that the number of matching calculations decreases as the constraint on the rate increases. 相似文献
77.
Inhibitory effects of some drugs on hepatic glucose 6-phosphate dehydrogenase from Lake Van fish (chalcalburnus tarischii pallas, 1811) were investigated. For this purpose, initially liver glucose 6-phosphate dehydrogenase was purified 899-fold in a yield of 46.24% by using 2',5'-ADP Sepharose 4B affinity gel. In order to control the purification of enzyme was done SDS polyacrylamide gel electrophoresis. SDS polyacrylamide gel electrophoresis showed a single band for enzyme. A constant temperature (+4 degrees C) was maintained during the purification process. Enzyme activity was determined with the Beutler method by using a spectrophotometer at 340 nm. Vankomycine, sulfanylamide, sulfanylacetamide, nidazole, ciprofloxacin, amoxicillin and KMnO(4) were used as drugs. These drugs exhibited inhibitory effects on the enzyme. IC(50) values of vankomycine, sulfanylamide, sulfanylacetamide, nidazole, ciprofloxacin, amoxicillin and KMnO(4) were 1.88, 0.037, 0.032, 1.178, 2.26, 643.5 and 0.0002 mM, and the K(i) constants 1.18+/-0.148, 0.119+/-0.021, 0.075+/-0.015, 1.15+/-0.21, 7.69+/-0.67, 1007+/-69, and 0.001+/-0.00022 mM, respectively. While vankomycine and nidazole showed competitive inhibition, others displayed noncompetitive inhibition. K(i) constants and IC(50) values for drugs were determined by Lineweaver-Burk graphs and plotting activity percentage versus [I], respectively. 相似文献
78.
Elvin Y. Malikov Melek C. Altay Oktay H. Akperov Mustafa B. Muradov Goncha M. Eyvazova Ákos Kukovecz 《Fullerenes, Nanotubes and Carbon Nanostructures》2018,26(5):255-262
Effect of sonication time on the synthesis of the CdS nanoparticles within the matrix obtained through the covalent functionalization of multiwall carbon nanotube (MWCNT) with maleic anhydride (MA) – 1-octene copolymer was investigated. Cadmium chloride and thiourea were used as the raw materials. MWCNTs used for the matrix were synthesized by Catalytic Chemical Vapor Deposition using Fe-Co/Al2O3 as the catalyst. The obtained nanostructures were characterized by FTIR, XRD, Raman spectroscopy, TEM, SEM, TG and UV-Vis spectroscopy. Electrophysical properties of the polymer nanocomposites obtained using different periods of time for sonication were comparably investigated. The average CdS particle diameter was between 3.9–7.9 nm as confirmed independently by TEM and XRD. UV-Vis spectroscopy revealed that the obtained nanostructures are appropriate base materials for making optical devices. 相似文献