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981.
F.EinarKruis 《中国颗粒学报》2005,3(1):67-67
A new procedure was developed for estimating the effective collision diameter of an aggregate composed of primary particles of any size. The coagulation coefficient of two oppositely charged particles was measured experimentally and compared with classic Fuchs theory, including a new method to account for particle non-sphericity. A second set of experiments were performed on well-defined nanoparticle aggregates at different stages of sintering, i.e. from the aggregate to the fully sintered stage. Here, electrical mobility was used to characterize the particle drag. The aggregates are being built from two different size-fractionated nanoparticle aerosols, the non-aggregated particles are discarded by an electrofilter and then they are passed through a furnace at concentrations low enough not to induce coagulation. 相似文献
982.
Wu Jiongqi 《Annals of Differential Equations》2005,21(4):592-597
In this paper N-dimensional singular, p-Laplace equations of the following form are considered, where p ≥N, β > 0, and f : [0,∞)×(0,∞)×[0, ∞)→[0,∞) is a continuous function. Some sufficient conditions are obtained for the existence of infinitely many radially positive entire solutions of the equation which are asymptotic to positive constant multiples of |x|(p-N)/(p-1) for p > N or log|x| for N = p as |x|→∞. 相似文献
983.
The studies undertaken to prepare the Technical Design Report of the ATLAS 3^rd Level Trigger(Event Filter)are performed on different prototypes based on different technologies.we present here the most recent results obtained for the supervision of the prototype based on conventional,off-the-shelf PC machines and Java Moblie agent technology. 相似文献
984.
985.
MICROSTRUCTURAL CHARACTERIZATION OF SPIN—VALVE MULTILAYERS BY X—RAY ANOMALYOUS DIFFRACTION TECHNIQUE
It is impossible to directly analyze the microstructure of spin-valve multilayers based on Ni,F,Cu and Mn by a conventional X-ray diffraction technique because the lattice parameter and atomic sattering factor sof them are very close.To solve this problem, we use an x-ray anomalous diffraction technique to characterize the microstructures of the [Ni80Fe20/Fe50Mn50]15 and [Ni80Fe20/Cu]15 superlattice systems.The results show that more diffraction peaks and higher internsity in the reflectivety profile are observed when the incident energy is close to the absorption edge of the lighter element(Mn) in [Ni80Fe20/Fe50Mn50]15 multilayer systems and to the absorption edge of the heavier element (Cu) in the [Ni80Fe20/Cu]15 multilayer systems.The interface and periodic structure of [Ni80F20/Fe50Mn50]15 are more perfect than that of the [Ni80Fe20/Cu]15 superlattices.The above results are disussed in this paper. 相似文献
986.
Martin M.F.Choi 《中国化学快报》2009,20(2):210-212
A novel mode-filtered light gas sensor has been reported.It was constructed by inserting an optical fiber deposited by a thin silicone cladding of cryptophane A into a fused-silica capillary.When different concentration of methane gas was introduced to the sensor,the phenomenon that mode-filtered light intensity decreased with the increasing concentration of methane was observed. And a linear relationship was obtained within the methane concentration range of 0.0-16.0%(v/v).The detection limit was 0.06% ... 相似文献
987.
988.
lntroductionThesmallolefinslikeethylene,propeneandbutenearethec0mmerciallydesirablepetrochemicalfeedstocksandarefoundincreasingusageinchemicalindustry.Theyareusuallyobtainedfromthepyrolysis0fpetroleumhydrocarb0nswithsteaInatveryhightemPeratUreandarealsoavailablefromFCCprocess.TheimProvedFCCcatalystforeIhancingtheolefinproducthasbeenreportedll].However,FCCisalrnostimPossiblefortheshortchainalkanefeedstockscutfrompetroleum0robtuinedfromrefinerygasornatUralgassincecrackingofhydrocarbonsbeco… 相似文献
989.
JIN Xiaofeng 《Chinese Journal of Lasers》1998,7(5):464-470
1IntroductionInterconnectionsofopticalwaveguidecomponentswithdiferentmodalspotsizes,particularlyfortheconnectionof(1)lasersou... 相似文献
990.
I.IntroductionInbeamformingforsonaritisthemostinterestingfunctionthatonecanobtainthctimcwaveformoutputsofthedesiredsignaltobedetectcdwithanimprovcdSignal-to-NoiseplusInterferenceRatio(SNIR).ItiswellknownthatMVDRbeamforminghasoptimumcapabi1i-hesofsignalprotection,interferenccremovalandnoisercduction.NootherbeamformingtochniquecanyicldalargerincreascinSNIR.Itspoweroutputcanbeusedasawavenumberspectrum(bearing)estimation,whoseprecisionorreso1utionisdeterminedprimarilybySignal-to-NoiseRatio… 相似文献