361   Size Dependence of Defect-Induced Room Temperature Ferromagnetism in Undoped ZnO Nanoparticles Size Dependence of Defect-Induced Room Temperature Ferromagnetism in Undoped ZnO Nanoparticles Xiaoyong Xu†‡, Chunxiang Xu*†, Jun Dai†, Jingguo Hu‡, Fengji Li§, and Sam Zhang§    2012 We report the intrinsic room-temperature ferromagnetism in undoped ZnO nanoparticles with different sizes synthesized by a wet chemical method at different temperatures. Electron paramagnetic resonance, X-ray photoelectron spectroscopy, and photoluminescence measurements demonstrate clearly the singly charged oxygen vacancies are the main defects, and the relative occupancy of that decreases with increasing sizes and annealing temperatures. Importantly, a direct correlation between the ferromagn 查看全文

362   Effects of ionic strength and nature of the cation on the desorption of fluoride from soil Effects of ionic strength and nature of the cation on the desorption of fluoride from soil Susann Balzar Ekenbck, Lars E. Linder, Marie-Louise Sund and Helena Louml;nnies    2006 The reaction between soil and added fluoride was accelerated by incubating at a high temperature. Desorption of the fluoride was then studied using solutions of chloride salts of several cations at a range of solution : soil ratios and for periods which ranged from 1 h to 4 days. Fluoride desorbed was related to the experimental variables by a regression equation. 查看全文

363   An improved iterative Born technique for ultrasound mammography An improved iterative Born technique for ultrasound mammography Lujiang Liu;Shira L. Broschat    0 In ultrasound mammography the objective is to image tumors about 4 or 5 mm in size. Thus the resolution of the reconstructed object profile is critical. Because of the strong refraction caused by fat lobes in the breast, simple pulse echo methods are inadequate, and a full inverse imaging technique is needed. The iterative Born method is an inverse technique that has been used in ultrasound imaging. However, the calculation cost is very high, and parallel computation is limited to the forward pr... 查看全文

364   Control of Six Contiguous Stereocenters in an Asymmetric Organocatalytic One-Pot Michael/Michael/Aldol Addition Sequence Control of Six Contiguous Stereocenters in an Asymmetric Organocatalytic One-Pot Michael/Michael/Aldol Addition Sequence Miguel Angel Prieto, Joseacute; Antonio Vaacute;zquez and Miguel Anxo Murado    2012 The asymmetric organocatalytic one-pot synthesis of polyfunctionalized cyclohexanes is described. Starting from β-keto esters, nitroalkenes and ,β-unstaturated aldehydes and employing a bifunctional norephedrine-based thiourea catalyst, six contiguous stereocenters including one quarternary center are generated. The one-pot protocol follows a Michael/Michael/aldol addition sequence and affords the highly substituted cyclohexanes in moderate to very good yields (22–70%), diastereo... 查看全文

365   DESIGN AND PERFORMANCE OF A HIGH REPETITION RATE SPARK GAP SWITCH AT 50-kW POWER LEVELS. DESIGN AND PERFORMANCE OF A HIGH REPETITION RATE SPARK GAP SWITCH AT 50-kW POWER LEVELS.    1980 Operation of a pressurized air, vortex-flow spark gap switch is reported for repetition rates greater than 1 kHz for 20-kA current pulses lasting less than 100 ns. Lowe jitter operation (less than plus or minus 5 ns absolute) has been achieved in a 36-J/pulse switching application. The design of the spark gap is discussed in terms of electrode and insulator heating, switch recovery, cooling requirements, gas flow geometries, electrode materials, electrode shapes, and erosion. Switch performance ... 查看全文

366   Synthesis of a Novel C2-Symmetric Bis-oxazoline (=Bis[4,5-dihydrooxazole]) and Its Application as Chiral Ligand in Asymmetric Transition Metal Catalysis Synthesis of a Novel C2-Symmetric Bis-oxazoline (=Bis[4,5-dihydrooxazole]) and Its Application as Chiral Ligand in Asymmetric Transition Metal Catalysis Xiaowei Zhang, Kexuan Huang, Guohua Hou, Bonan Cao and Xumu Zhang    2012 The new C2-symmetric bis-oxazoline (=bis[4,5-dihydrooxazole]) 2 with a chiral trans-(2R,3R)-2,3-bis(3,5-diphenylphenyl)cyclopropylidene (=trans-(2R,3R)-2,3-bis([1,1′: 3′,1″-terphenyl]-5′-yl)cyclopropylidene) backbone was efficiently synthesized (Scheme). All synthetic steps were easy to perform. and led to the desired product in good overall yields. Compound 2 was tested and compared as ligand in several enantioselective catalytic reactions such as palladium(0)-cat... 查看全文

367   FIRST OPERATION OF THE TASCC BEAM BUNCHING SYSTEM. FIRST OPERATION OF THE TASCC BEAM BUNCHING SYSTEM.    1985 The Chalk River Tandem Accelerator Superconducting Cyclotron (TASCC) system uses a low-energy buncher (LEB) and a high-energy rebuncher (HEB) to produce the required bunched beam at the cyclotron injection stripper foil. The LEB modulates the less than equivalent to 300 keV beam from the negative ion source with a fundamental plus 2nd harmonic approximation to an ideal sawtooth to give a time focus at the stripper in the tandem accelerator terminal. The HEB, operating at the 2nd or 4th harmonic,... 查看全文

368   Broadband electrical design and modelling of packages integrated in LTCC-substrate Broadband electrical design and modelling of packages integrated in LTCC-substrate    2003 Substrate integrated package based on LTCC-technology with bandwidth of 50 GHz was designed. Full wave electromagnetic analysis of all included interconnects was performed and verified by measurement. Our work is especially focused on novel interconnects like flip-chip and differential transmission lines which enable an increase of bandwidth of the components. For the design of high speed SiGe-chips which will be embedded in LTCC-packages and modules it is interesting to know the influence of wi... 查看全文

369   Structural Study-Guided Development of Versatile Phase-Transfer Catalysts for Asymmetric Conjugate Additions of Cyanide† Structural Study-Guided Development of Versatile Phase-Transfer Catalysts for Asymmetric Conjugate Additions of Cyanide† Henri Brunner and Reinhard Stouml;riko    2011 查看全文

370   Voltage-to-frequency TDMA digital light-emitting cartography using photosynchronization Voltage-to-frequency TDMA digital light-emitting cartography using photosynchronization    2004 The measurement of the potential on the living body is much vulnerable to the electric induction noise. To avoid such induction, a novel principle for the cardiography is proposed. In the electrography, the sensing signal of cardiography is transmitted in open air by the light from LED. The electrocardiograph transmits 12-channel signals of electrical potential on a living body. In this report, the multichannel transmission is realized by the TDMA system. The TDMA system needs essentially the sy... 查看全文

371   Pseudo-phase-matched four-wave mixing in soliton wavelength-division multiplexing transmission Pseudo-phase-matched four-wave mixing in soliton wavelength-division multiplexing transmission    1996 The performance of dispersion-tapered fiber is investigated for use in the production of massive wavelength-division multiplexing (WDM) with solitons. Several issues are considered. Among them is the dispersion management that can avoid penalty from the effects of cross-phase modulation. An application shows the viability of an error-free soliton WDM transmission at 6 × 10 and 7 × 10 Gbit/s over paths of 11.4 and 9.4 Mm, respectively. 查看全文

372   Composition/Structure Relationships in Monolithic Borophosphosilicate Glasses Obtained by the Sol−Gel Route Composition/Structure Relationships in Monolithic Borophosphosilicate Glasses Obtained by the Sol−Gel Route C. Canevali,* R. Scotti, A. Vedda, M. Mattoni, and F. Morazzoni*    2003 Monolithic borophosphosilicate glasses were prepared by the sol?gel route through xerogel densification. Tetramethoxysilane (Si(OCH3)4), trimethylborate (B(OCH3)3), and trimethyl phosphite (P(OCH3)3) were used as source compounds for Si, B, and P, respectively. After drying, samples underwent thermal treatment up to 700 °C with alternating flowing oxygen and reduced pressure steps, resulting in transparent, monolithic glasses. The sample chemical composition was analyzed by X-ray photoelectron ... 查看全文

373   FAST SCINTILLATOR MODULE WITH UNIFORM. RESPONSE. FAST SCINTILLATOR MODULE WITH UNIFORM. RESPONSE.    1981 A scintillator module with an active area of 35 multiplied by 35 cm**2 and with an air light guide to a phototube located 40 cm behind the scintillator is described. The time jitter across the active area is plus or minus 0. 1 ns and the time resolution 0. 5 ns. The variation in amplitude over the active surface is plus or minus 7%. 查看全文

374   Corrigendum: Synergistic Effect: Hydroalkoxylation of Allenes through Combination of Enantiopure BIPHEP-Gold Complexes and Chiral Anions Corrigendum: Synergistic Effect: Hydroalkoxylation of Allenes through Combination of Enantiopure BIPHEP-Gold Complexes and Chiral Anions Yuta Suzuki, Ryo Yazaki, Dr. Naoya Kumagai and Prof.;Dr. Masakatsu Shibasaki    2011 查看全文

375   GHz regeneratively synchronized passively mode-locked fiber laser for spectrum generation in the 1.5-μm region GHz regeneratively synchronized passively mode-locked fiber laser for spectrum generation in the 1.5-μm region    2000 A study was carried out to demonstrate for the first time that synchronized pulses from a polarization additive pulse mode-locking (P-APM) laser lead to RF suppression comparable to, pulsewidth shorter than, and amplitude noise superior to its solitonically shorted actively mode-locked counterparts. Amplification shortened the pulsewidth to 304 fs. The resulting continuum after the dispersion decreasing fiber (DDF) concentrated most of its energy in the EDFA bandwidth. The spectral intensity var... 查看全文

376   Arachnids (Arachnidae) in a Spring Wheat Agrocenosis in Southern Sverdlovsk Oblast and the Effect of Treatment with Decis, a Pyrethroid Insecticide, on Their Populations Arachnids (Arachnidae) in a Spring Wheat Agrocenosis in Southern Sverdlovsk Oblast and the Effect of Treatment with Decis, a Pyrethroid Insecticide, on Their Populations E. A. Bel'skaya;S. L. Esyunin    2003 查看全文

377   Highly Enantioselective Epoxidation of Multisubstituted Enones Catalyzed by Non-Heme Iron Catalysts Highly Enantioselective Epoxidation of Multisubstituted Enones Catalyzed by Non-Heme Iron Catalysts Paulo Dani, Thomas Karlen, Robert A. Gossage, Serafino Gladiali and Gerard van Koten    2012 查看全文

378   Lipids Out of Equilibrium:  Energetics of Desorption and Pore Mediated Flip-Flop Lipids Out of Equilibrium:  Energetics of Desorption and Pore Mediated Flip-Flop D. Peter Tieleman*† and Siewert-Jan Marrink*‡;    2006 The potential of mean force (PMF) of a phospholipid in a bilayer is a key thermodynamic property that describes the energetic cost of localized lipid defects. We have calculated the PMF by umbrella sampling using molecular dynamics simulations. The profile has a deep minimum at the equilibrium position in the bilayer and steeply rises for displacements both deeper into the bilayer and moving away from the bilayer. As the lipid loses contact with the bilayer, the profile abruptly flattens without... 查看全文

379   EDITOR'S PAGE: A Special Issue Edited by a Special Person EDITOR'S PAGE: A Special Issue Edited by a Special Person Ronald D. Simpson    2000 查看全文

380   Application of microbes to the soils of Siberian tree nurseries Application of microbes to the soils of Siberian tree nurseries I. D. Grodnitskaya;N. D. Sorokin    2007 The introduction of Trichoderma viride spores (108 CFU per 1 cm2) essentially changed the structure of micromycetes in the soils of tree nurseries in Krasnoyarsk region. During the first 20 days, in the variants with dark gray forest soils and podzolized chernozems, the total number of fungi decreased by 3–4 and 1.5 times, respectively, as compared to that in the control plots. During the intense development of the introduced microbes, the species composition of the... 查看全文

381   Primate Communities. Edited by John G. Fleagle, Charles Janson, and Kaye E. Reed Primate Communities. Edited by John G. Fleagle, Charles Janson, and Kaye E. Reed Alex;er H. Harcourt    2000 查看全文

382   Microstructure-property relationship in nitrogen doped Ge2Sb2Te5 phase-change optical recording media Microstructure-property relationship in nitrogen doped Ge2Sb2Te5 phase-change optical recording media    1998 The variation of thermal, optical and dynamic properties, and their correlation to microstructure in nitrogen-doped Ge2Sb2Te5 phase-change recording media was investigated. The addition of optimum amount of nitrogen in Ge-Sb-Te alloy increased the crystallization temperatures and activation energy barrier against crystallization. The phase change optical disks led to an enhanced recording sensitivity, extended data retention time, and reduced overwrite jitter resulting in longer media cyclabilit... 查看全文

383   Performance studies of lead/scintillating-fibre calorimeters in the 1 to 10 GeV range Performance studies of lead/scintillating-fibre calorimeters in the 1 to 10 GeV range    1994 Three calorimeter modules made of scintillating fibres embedded in a lead matrix were tested at the CERN Proton Synchrotron. The linearity of the energy response to electron-induced showers, measured in a module having a lead-to-fibre volume ratio of 1.8, is verified within 2.5% whilst the energy resolution is found to be 9.6%/√E+1% at 6° and 4° impact angles in the horizontal and vertical planes. An impact position resolution of 1.51 mm/√E+1.45 mm is achieved. The e/π&plu... 查看全文

384   IMPORTANCE OF RAPID DAMPING OF RELAXATION OSCILLATIONS FOR HIGH-PERFORMANCE OPTICAL COMMUNICATION SYSTEMS. IMPORTANCE OF RAPID DAMPING OF RELAXATION OSCILLATIONS FOR HIGH-PERFORMANCE OPTICAL COMMUNICATION SYSTEMS.    1986 The performance of a 1. 55 mu m lightwave transmission system employing directly modulated single-frequency semiconductor lasers depends on the dynamic characteristics such as the wavelength chirp and the damping of relaxation oscillations. Numerical simulations which include the effect of fibre dispersion and decision-time jitter on the detected power show that rapid damping of relaxation oscillations is critically important for high-bit-rate systems. We discuss how the system performance can b... 查看全文

385   Proceedings of SPIE: Laser Systems Technology Proceedings of SPIE: Laser Systems Technology    2003 The proceedings contain 19 papers from the Conference on Proceedings of SPIE: laser system technology. Topics discussed include: laser beam steering and tracking using a liquid crystal spatial light modulator; tracking system with PCM laser for space control applications; angular vibration survey of various aircraft; joint time-frequency transform. processing for linear and sinusoidal FM coherent ladars; tracking through laser-induced clutter for air-to-groud directed energy systems and beacon a... 查看全文

386   4 GHz all-optical clock recovery using a self-pulsating multielectrode distributed feedback laser 4 GHz all-optical clock recovery using a self-pulsating multielectrode distributed feedback laser    1995 The authors report for the first time, an experimental all-optical clock extraction obtained with 13 nm wavelength deviation. Under optimum polarization conditions, a 11.5 ps time-jitter and a 7 dB extinction ratio are measured at 3.8 Gbit/s by injecting an intensity modulated return to zero data stream to a 1.5 μm self-pulsating three-section DFB laser. 查看全文

387   The generation of spatial soliton arrays in a planar Kerr waveguide from seeded spontaneous parametric down conversion The generation of spatial soliton arrays in a planar Kerr waveguide from seeded spontaneous parametric down conversion    2004 The possibility of generating spatial soliton arrays in a nonlinear Kerr waveguide by the spontaneous modulation instability (MI) process strongly depends on the relaxation time of the nonlinear material response and on the characteristics of the spatio-temporal noise added on the injected beam. We address this issue in this paper by considering parametric down conversion generated in a quadratic crystal as a noise source before the Kerr waveguide. By a full spatio-temporal numerical simulation,... 查看全文

388   10 and 20Gbit/s clock recovery GaAs IC with 288 phase-shifting function 10 and 20Gbit/s clock recovery GaAs IC with 288 phase-shifting function    1996 A 10 and 20Gbit/s clock recovery IC with 180° switched and 288° continuously variable phase-shifting function has been realised using 0.2/0.3μm HEMT technology. The recovered clock signal has a time jitter of 2ps at 10GHz. The 2 × 1.5mm2 IC needs 300mW DC power at -3.3V supply. 查看全文

389   Legal Reforms In Congress May Change Product Liability Laws Legal Reforms In Congress May Change Product Liability Laws MARC S. REISCH    1995 Dow Corning, the silicones-producing joint venture of Dow Chemical and Corning, has spent millions of dollars defending itself against consumer complaints that its silicone breast implants made women ill. Faced with 19,000 individual suits, and a possible increase in its $2 billion contribution to the $4 billion global breast implant settlement, Dow Corning sought bankruptcy protection last month. 查看全文

390   Classifying Arsonists -- Offender Behaviour and Characteristics Classifying Arsonists -- Offender Behaviour and Characteristics Claire Nee    1998 查看全文

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