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101.
Two consequences of coherence of mesonic fields have been tested in proton-nucleus collisions. Multiplicity fluctuations measured in finite rapidity intervals are found to obey a Poisson distribution at large rapidities where nuclear transparency occurs. In close analogy to quantum optics we present a quark-parton model in which this link between coherence and transparency is realized via the phenomenon of self-induced transparency. 相似文献
102.
M. Diakonou C. Kourkoumelis L.K. Resvanis T.A. Filippas E. Fokitis C. Trakkas A.M. Cnops E.C. Fowler D.M. Hood R.B. Palmer D.C. Rahm P. Rehak I. Stumer C.W. Fabjan T. Fields D. Lissauer I. Mannelli W. Molzon W.J. Willis 《Physics letters. [Part B]》1980,91(2):296-300
We have measured direct photon production in pp collisions at the CERN intersecting storage rings for c.m. energies 31 < √s < 63 GeV and transverse momenta up to 9GeV/c, using segmented lead/liquid-argon calorimeters. The ratio of direct photon to π0 production is significantly larger than zero, starting at pT ≈ 4 GeV/c and increasing to values of about 0.4 at 9GeV/c. No significant √s dependence is seen. 相似文献
103.
104.
105.
Helen Elaine Howard-Lock Colin James Lyne Lock Philip Stuart Smalley 《Journal of chemical crystallography》1983,13(5):333-353
The X-ray crystal structure of a racemic mixture of D- and L-penicillamine has been determined. Crystals are monoclinic,P21/c (No. 14), with cell dimensionsa=11.624(3),b=5.919(1),c=11.482(2) Å,β=114.48(2)°, andZ=2, based on the racemate. The structure was determined by standard methods and refined toR 1=0.0666,R 2=0.0726 for 985 independent reflections. Bond lengths and bond angles do not differ from those in similar structures. Mass spectra and1H and13C NMR spectra are reported ford-penicillamine, and detailed infrared and Raman spectra are reported for solidd-penicillamine hydrochloride,d 5-d-penicillamine hydrochloride,d-penicillamine,d 4-d-penicillamine, anddl-penicillamine. The Raman spectrum ofd-penicillamine in H2O solution as a function of pH is also reported. 相似文献
106.
Peter Fowler 《The Journal of the Operational Research Society》1970,21(4):477-477
107.
108.
An extensive failure analysis of the steepest-descent optimization algorithm has been made. Each of the ways in which the algorithm can fail is discussed in terms of both the mathematical and numerical manifestations of a failure and the information which each type of failure provides about the formulation of the physical problem. Numerical tests for each of the various types of failure are described; several faulty problem formulations are presented, each of which illustrates a particular type of failure. A table is presented in which all failure modes are summarized and the corresponding numerical tests are exhibited. 相似文献
109.
R.G. Fowler 《Physics letters. A》1978,65(3):239-240
It is suggested that recent beam experiments which were designed to disprove Bohm diffusion may instead have revealed the existence of unsuspected magnetic effects upon recombination. 相似文献
110.
The equilibrium quotients for the formation of Co(NH3)5Cl2+ from Co(NH3)5OH23+ and Cl? were 3.74±0.25 M?1 and 6.07±0.54 M?1 at 45.0°C in 10:1 mole ratio water: dimethyl sulfoxide and in 25 w/w % aqueous ethanol, respectively, and those forthe formation of the ion pair Co(NH3)5OH23+ . Cl? were 1.21±0.20 M?1 and 1.58±0.17 M?1, respectively, in the same solvents. The aquation and anation rateconstants were determined at 45.0°C for these two solvents over the range of chloride-ion concentrations 0.0 ≤ [Cl?] ≤ 0.9 M. The aquation rate constant was essentially independent of chloride-ion concentration in each solvent over this range. The inverse of the pseudo-first-order anation rate constant was linearly dependent on the inverse of the chloride-ion concentration in each solvent. The least squares relationships between (1/kan) and (1/[Cl?]) gave intercepts and ratios of intercept to slope which were analyzed interms of Id and D mechanisms. It was concluded that the data were not satisfied by a D mechanism, but that they were consistent with an Id mechanism. 相似文献