Tensorial strength analysis of paperboard

Tensorial-type failure criteria with linear and quadratic terms are used to calculate the strength of paperboard under plane stress. Theoretical predictions and experimental data are correlated in all four quadrants of biaxial normal stress with various levels of shear. Several methods are examined for determining the interaction coefficientF ₁₂. Comparisons are made with optimum values obtained from least-squares analyses. The best analytical-experimental agreement at all levels of shear is obtained approximately by using coefficientF ₁₂ equal to zero. The sensitivity ofF ₁₂ to errors in experimental input data is also studied. Reliable correlation with experiment, as well as operational simplicity, make these criteria attractive for predicting the strength of paperboard.     

A laser extraction/combustion technique for in situ delta(13)C analysis of organic and inorganic materials

A CO(2) laser extraction system is described for in situ delta(13)C analysis of organic and inorganic materials. Carbonaceous compounds volatilized by the laser are quantitatively converted to CO(2) gas by a combustion furnace mounted after the sample chamber. Gases produced by the laser and combustion processes are swept by helium carrier gas and separated by a packed gas chromatography column prior to their introduction to an isotope ratio monitoring mass spectrometer. A sample of lentil bean was analyzed at a spatial resolution of 200 μm and yielded delta(13)C values with precision of +/- 0.3 per thousand. The accuracy of delta(13)C measurements was better than +/- 0.5 per thousand from NBS 22 (mineral oil), USGS 24 (graphite), and IAEA CO-1 (calcium carbonate). Copyright 1999 John Wiley & Sons, Ltd.     

The time of graph bootstrap percolation

Graph bootstrap percolation, introduced by Bollobás in 1968, is a cellular automaton defined as follows. Given a “small” graph H and a “large” graph , in consecutive steps we obtain from G_t by adding to it all new edges e such that contains a new copy of H. We say that G percolates if for some , we have G_t = K_n. For H = K_r, the question about the size of the smallest percolating graphs was independently answered by Alon, Frankl and Kalai in the 1980's. Recently, Balogh, Bollobás and Morris considered graph bootstrap percolation for and studied the critical probability , for the event that the graph percolates with high probability. In this paper, using the same setup, we determine, up to a logarithmic factor, the critical probability for percolation by time t for all © 2016 Wiley Periodicals, Inc. Random Struct. Alg., 51, 143–168, 2017     

Two new water-soluble derivatives of 1,3,5-triaza-7-phosphaadamantane (PTA): Synthesis,characterization, X-ray analysis and solubility studies of 3,7-diformyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane and 1-pyridylmethyl-3,5-diaza-1-azonia-7-phosphatricyclo[3.3.1.1]decane bromide

Two water-soluble phosphines, 3,7-diformyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane (1, DFPTA) and 1-pyridylmethyl-3,5-diaza-1-azonia-7-phosphatricyclo[3.3.1.1]decane bromide (2, [pymePTA]Br), have been respectively, prepared by reacting 1,3,5-triaza-7-phosphaadamantane (PTA) with formic anhydride and bromomethylpyridine. Compound 1 is only the second acyl derivative of PTA to be prepared while 2 is only the second derivative of PTA reported that contains an aromatic appendage. Both compounds were characterized by elemental analysis, FAB-MS, ¹H, ¹³C, and ³¹P NMR spectroscopy, and single crystal X-ray diffraction. This analysis showed that the formamide groups of 1 were in an anti confirmation in solution but in a syn confirmation in the solid state. The solubilities of 1 and 2 were examined in common organic solvents and water. It was found that 1.1 M aqueous solutions of 1 could be prepared while 2.4 M solutions of 2 were produced. The greater solubility of 2 was likely due to its ionic nature.     

Coherent production ofρ − mesons in charged current antineutrino-neon interactions in BEBC

Coherent production ofρ ^? mesons in charged current antineutrino interactions on neon nuclei is studied in the BEBC bubble chamber exposed to the CERN SPS wide band beam. The cross section is measured to be (95±25)·10^?40 cm² per neon nucleus, averaged over the beam energy spectrum. The distributions of kinematical variables and the absolute value of the cross section are in agreement with theoretical predictions based on the CVC hypothesis and the vector meson dominance model.     

Evidence for higher twist effects in fast π− production by antineutrinos in neon

Evidence for a significant higher twist contribution to highz π^? production in antineutrino scattering is presented. In events withW>3 GeV andQ ²>1 GeV² in our data, it accounts for (51 ±8)% of all π^? withz above 0.5. It is consistent with thez?Q ² correlations of Berger's higher twist prediction. The data are inconclusive concerning the predictedy?z correlation andp _T dependence. Thez ?Q ² correlation is not adequately described by the Lund Monte-Carlo.     

Transverse energy production in the target fragmentation region in16O-nucleus reactions at 60 and 200A GeV

Charged pion yields and transverse energies of baryons are measured for the reaction¹⁶O+Cu, Ag, Au at 60 and 200A GeV bombarding energy in the target fragmentation region employing the Plastic Ball detector. Only little dependence of the measured quantities on the bombarding energy is found. The data are compared with the multi-chain fragmentation model of Ranft. As a result it turns out that a leading order formation zone cascade is not sufficient to explain the baryon yield and the transverse energies of baryons in the target fragmentation region.     

High transverse momentum prompt photon production by π− and π+ on protons at 280 GeV/c

The inclusive cross sections for prompt photon production by π^? and π⁺ on protons have been measured with a beam momentum of 280 GeV/c using a fine grained electromagnetic calorimeter and the CERN Omega spectrometer. The transverse momentum and Feynmanx _F ranges covered are 4.0<p _T <7.0GeV/c and ?0.45<x _F <0.55 respectively. A quantitative comparison of the prompt photon cross section with next-to-leading order QCD predictions using Duke and Owens structure functions is performed.     

Oxygen-induced reactions at 60A GeV and 200A GeV studied by calorimetry

Results based on calorimetric measurements are presented from reactions of 60A GeV and 200A GeV¹⁶O projectiles with C, Cu, Ag, and Au nuclei. Minimum-bias cross sections are discussed. Energy spectra measured at zero degrees and transverse-energy distributions for the pseudorapidity range 2.4≦η≤5.5 are shown. An analysis of the average transverse energy in terms of the number of participating nucleons and the number of binary nucleon-nucleon collisions is presented. Estimates of nuclear stopping and of attained energy densities are made.     

Conditioning of linear boundary value problems

The method of parallel shooting for the solution of two-point boundary value problems is investigated. Bounds are obtained for the norms of the fundamental matrices of the differential equations and their inverses. These bounds are used for estimation of the condition number and for determining the shooting intervals.This research was supported by NASA Grant No. NGR-002-016.Visiting Utah State University, Summer, 1971.