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141.
Close contacts between chalcogen atoms in cyclic dienes and diynes are used to create columnar structures in the solid state. Rigid and fairly planar cycles with chalcogen centers are the preconditions for forming those columnar structures. 相似文献
142.
143.
Abazov VM Abbott B Abdesselam A Abolins M Abramov V Acharya BS Adams DL Adams M Ahmed SN Alexeev GD Alves GA Amos N Anderson EW Arnoud Y Baarmand MM Babintsev VV Babukhadia L Bacon TC Baden A Baldin B Balm PW Banerjee S Barberis E Baringer P Barreto J Bartlett JF Bassler U Bauer D Bean A Beaudette F Begel M Belyaev A Beri SB Bernardi G Bertram I Besson A Beuselinck R Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Bos K Brandt A Breedon R 《Physical review letters》2002,88(17):171802
We have performed a search for scalar top quark (stop) pair production in the inclusive electron-muon-missing transverse energy final state, using a sample of pp events corresponding to 108.3 pb(-1) of data collected with the D0 detector at Fermilab. The search is done in the framework of the minimal supersymmetric standard model assuming that the sneutrino is the lightest supersymmetric particle. For the dominant decays of the lightest stop, t-->b chi+1 and t-->blnu, no evidence for signal is found. We derive cross-section limits as a function of stop ( t ), chargino ( chi+1), and sneutrino ( nu) masses. 相似文献
144.
Bertram HC Rasmussen M Busk H Oksbjerg N Karlsson AH Andersen HJ 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2002,157(2):267-276
This study investigates the effects of developmental stage and muscle type on the mobility and distribution of water within skeletal muscles, using low-field (1)H-NMR transverse relaxation measurements in vitro on four different porcine muscles (M. longissimus dorsi, M. semitendinosus, M. biceps femoris, M. vastus intermedius) from a total of 48 pigs slaughtered at various weight classes between 25 kg and 150 kg. Principal component analysis (PCA) revealed effects of both slaughter weight and muscle type on the transverse relaxation decay. Independent of developmental stage and muscle type, distributed exponential analysis of the NMR T(2) relaxation data imparted the existence of three distinct water populations, T(2b), T(21), and T(22), with relaxation times of approximately 1-10, 45-120, and 200-500 ms, respectively. The most profound change during muscle growth was a shift toward faster relaxation in the intermediate time constant, T(21). It decreased by approx. 24% in all four muscle types during the period from 25 to 150 kg live weight. Determination of dry matter, fat, and protein content in the muscles showed that the changes in relaxation time of the intermediate time constant, T(21), during growth should be ascribed mainly to a change in protein content, as the protein content explained 77% of the variation in the T(21) time constant. Partial least squares (PLS) regression revealed validated correlations in the region of 0.58 to 0.77 between NMR transverse relaxation data and muscle development for all the four muscle types, which indicates that NMR relaxation measurements may be used in the prediction of muscle developmental stage. 相似文献
145.
Bertram Huppert 《Archiv der Mathematik》1969,19(6):561-574
Ohne Zusammenfassung 相似文献
146.
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148.
F.?von Gynz-Rekowski N.?Bertram G.?Gantef?r Y. D.?KimEmail author 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,36(2):187-191
The reaction of oxygen with Cu cluster anions consisting of 6–11 atoms was
studied by means of Time-of-Flight mass (TOF) spectroscopy and Ultraviolet
Photoelectron Spectroscopy (UPS). Using molecular oxygen, we found that a
Cu-n cluster (n=6-11) can react only with one single oxygen
molecule, which adsorbs molecularly, implying that the clusters studied here
are less reactive towards oxygen chemisorption compared to the smaller
clusters (n<5). This result indicates that chemical properties can alter
significantly with increasing cluster size. Depending on the cluster source
conditions, different cluster structures and reactivity patterns were found.
These results are used to qualitatively describe the chemisorption
energetics of oxygen on Cu cluster anions. 相似文献
149.
Abazov VM Abbott B Abolins M Acharya BS Adams M Adams T Agelou M Agram JL Ahn SH Ahsan M Alexeev GD Alkhazov G Alton A Alverson G Alves GA Anastasoaie M Andeen T Anderson S Andrieu B Arnoud Y Askew A Asman B Jesus AC Atramentov O Autermann C Avila C Badaud F Baden A Baldin B Balm PW Banerjee S Barberis E Bargassa P Baringer P Barnes C Barreto J Bartlett JF Bassler U Bauer D Bean A Beauceron S Begel M Bellavance A Beri SB Bernardi G Bernhard R Bertram I Besançon M Beuselinck R Bezzubov VA 《Physical review letters》2005,95(5):051802
We present a measurement of the Zgamma production cross section and limits on anomalous ZZgamma and Zgammagamma couplings for form-factor scales of lambda = 750 and 1000 GeV. The measurement is based on 138 (152) candidates in the eegamma (mumugamma) final state using 320(290) pb(-1) of pp(-1) collisions at square root of s = 1.96 TeV. The 95% C.L. limits on real and imaginary parts of individual anomalous couplings are /h(10,30)Z/ < 0.23, /h(20,40)Z/ < 0.020, /h(10,30)gamma/ < 0.23, and /h(20,40)gamma/ < 0.019 for lambda = 1000 GeV. 相似文献
150.
The recent torsional oscillator results of Kim and Chan suggest a supersolid phase transition in solid 4He confined in Vycor. We have used a capacitive technique to directly monitor density changes for helium confined in Vycor at low temperature and have used a piezoelectrically driven diaphragm to study the pressure-induced flow of solid helium into the Vycor pores. Our measurements showed no indication of a mass redistribution in the Vycor that could mimic supersolid decoupling and put an upper limit of about 0.003 microm/s on any pressure-induced supersolid flow in the pores of Vycor. 相似文献