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991.
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994.
Measurements of 19F ENDOR for the Ce3+ unswitched photochromic centre in CaF2 confirm that the centre comprises a Ce3+ ion associated with a nearest neighbour F- vacancy containing two electrons (an F′ centre). 相似文献
995.
996.
Kenneth R. Baker 《The Journal of the Operational Research Society》1970,21(3):335-340
A discussion is presented of a class of operating policies which employ the familiar "newsboy" relationship in more complicated multi-item production-inventory systems. 相似文献
997.
Rohe D Armstrong CS Asaturyan R Baker OK Bueltmann S Carasco C Day D Ent R Fenker HC Garrow K Gasparian A Gueye P Hauger M Honegger A Jourdan J Keppel CE Kubon G Lindgren R Lung A Mack DJ Mitchell JH Mkrtchyan H Mocelj D Normand K Petitjean T Rondon O Segbefia E Sick I Stepanyan S Tang L Tiefenbacher F Vulcan WF Warren G Wood SA Yuan L Zeier M Zhu H Zihlmann B;E- Collaboration 《Physical review letters》2004,93(18):182501
We have carried out an (e,e'p) experiment at high momentum transfer and in parallel kinematics to measure the strength of the nuclear spectral function S(k,E) at high nucleon momenta k and large removal energies E. This strength is related to the presence of short-range and tensor correlations, and was known hitherto only indirectly and with considerable uncertainty from the lack of strength in the independent-particle region. This experiment locates by direct measurement the correlated strength predicted by theory. 相似文献
998.
Abe M Aliev M Anisimovsky V Aoki M Asano Y Baker T Blecher M Depommier P Hasinoff M Horie K Igarashi Y Imazato J Ivashkin AP Khabibullin MM Khotjantsev AN Kudenko YG Kuno Y Lee KS Levchenko A Lim GY Macdonald JA Mineev OV Okorokova N Rangacharyulu C Shimizu S Shin YH Shin YM Sim KS Yershov N Yokoi T;KEK-E Collaboration 《Physical review letters》2004,93(13):131601
A search for T-violating transverse muon polarization (P(T)) in the K+-->pi(0)mu(+)nu decay was performed using kaon decays at rest. A new improved value P(T)=-0.0017+/-0.0023(stat)+/-0.0011(syst) was obtained giving an upper limit |P(T)|<0.0050. The T-violation parameter was determined to be Imxi=-0.0053+/-0.0071(stat)+/-0.0036(syst) giving an upper limit |Imxi|<0.016. 相似文献
999.
Deformability of poly(amidoamine) dendrimers 总被引:1,自引:0,他引:1
Mecke A Lee I Baker JR Holl MM Orr BG 《The European physical journal. E, Soft matter》2004,14(1):7-16
Experimental data indicates that poly(amidoamine) (PAMAM) dendrimers flatten when in contact with a substrate, i.e. they are no longer spherical, but resemble flat disks. In order to better understand the deformation behavior of these branched polymers, a series of atomistic molecular dynamics simulations is performed. The resulting flattened dendrimer conformations are compared to atomic force microscopy (AFM) images of individual dendrimers at air/mica and water/mica interfaces. The ability of the polymers to deform is investigated as a function of dendrimer generation (2-5) and the required energies are calculated. Our modeling results show good agreement with the experimental AFM images, namely that dendrimers are highly flexible and capable of forming multiple interaction sites between most of their branch ends and the substrate. The deformation energy scales with dendrimer generation and does not indicate an increase in stiffness between generations 2 and 5 due to steric effects.PACS:
81.07.Nb Molecular nanostructures - 82.20.Wt Computational modeling; simulation - 68.37.Ps Atomic force microscopy (AFM) 相似文献
1000.
A self-referencing optical thermometer based on a reversible, temperature-dependent monomer-excimer interconversion of 1,3-bis(1-pyrenyl)propane dissolved in an ionic liquid and operating in the 25 to 140 degrees C range is reported. 相似文献