Determination of the correlation between physical measurements of roughness, optical properties, and perception of frosted glass surfaces

Chemical frosting is used as a surface decorating method by many glass package producers. After immersion in an acid frosting bath, glass items present the desired frosted effect. The perception of this particular effect is due to the formation of a microscopic crystalline pattern on the glass surface, which scatters light passing through the glass surface. The chemical composition of the frosting bath influences these properties by modifying the surface roughness, the depth, and the average slopes of the crystalline pattern. Perception of the final aspect can be modified according to the chemical composition of the frosting bath. Different correlations between all these parameters exist and have been quantified.     

Update of line parameters of ozone in the 2550-2900 cm(-1) region

An update of spectroscopic line parameters for the 3.45-3.92 microm ozone bands is reported. The line list includes the parameters of 15 bands of the main isotopic species and of the v1+v2+v3 band of 16O16O18O and 16O18O16O. The results are based on previous high resolution laboratory studies. Comparisons of experimental spectra with an absorptance simulation of ozone based on the reported line list shows that the latter one is accurate enough for strong, medium, and weak transmittance in the 2550-2900 cm(-1) spectral range. The data are available on the Web in the Spectroscopy and Molecular Properties of Ozone (S&MPO, http://smpo.iao.ru and http://ozone.univ-reims.fr) and HITRAN (http://cfa-www.harvard.edu/hitran/) databanks.     

New Raman spectrometer using a digital micromirror device and a photomultiplier tube detector for rapid on-line industrial analysis. Part II: Choice of analytical methods

In this paper, the performances of four improved analytical methods (backward stepwise selection of peak intensities, sum of characteristic peaks of a component, moving window partial least squares, and genetic algorithms) using wavelength selection for the analysis of xylene mixtures by Raman spectroscopy are tested for further use on the new "digital micromirror device associated with a photomultiplier tube" Raman spectrometer. It is shown that the errors of prediction using only a few selected points (from 4 to 49 depending on the method) are almost the same as when using the whole spectral range (1050 points). Compared to the last two methods, the "backward stepwise selection of peak intensities" and "sum of characteristic peaks of a component" methods are robust under industrial conditions and appear to be well suited for chemical quantitative analysis with the new Raman spectrometer, which allows the measurements of the total intensity to be made simultaneously for a number of pre-selected frequencies. Results show that the errors of prediction can be near to or even lower than 2%.     

Metrological significance of the column test in the assessment of the static segregation of self-compacting concrete in the fresh state

As stated by previous studies, the column test seems to be relevant for the evaluation of the state of segregation of self compacting concrete (SCC) at rest. However, the available information shows a great diversity of apparatus, procedures, aggregate sizes analyzed and segregation indexes. Based on repeatability procedures and statistical analysis of SCC compositions of the French National Project on SCC (PN B@P), this study is aimed particularly at defining what objective sieve size must be chosen to discriminate a real segregation state. When the values of the various indexes proposed in the literature are calculated as a function of sieve size from 2.5 mm, the results show significant variations in the indexes, which are not always explained by a significant segregation in the coarsest aggregate sizes. When segregation does not exist, these variations may be due to a random distribution of the coarsest aggregates. An optimal sieve size D_opt ranging from 0.5.D_max to 0.625.D_max is suggested (D_max, maximum gravel size in the grading curve of concrete) which should ensure correct segregation analysis. In addition trends, but no strong relationships, are noted between the index values calculated from D_opt and the associated criteria.     

Effect of nanoconfinement on the collapse transition of responsive polymer brushes

Nanopatterned brushes of a thermo-responsive polymer, poly(2-(2-methoxyethoxy)ethyl methacrylate) (PMEO2MA), displaying a collapse temperature in the physiological range were synthesized for grafting diameters from a few micrometers down to 35 nm. The reversible collapse transition of the nanobrushes was studied in water as a function of their lateral confinement, down to ensembles of brushes containing only approximately 300 chains. The confinement results in a considerable broadening of the collapse transition and in an increase of the degree of vertical swelling, which can be explained by the internal structure of the nanodroplets derived from a theoretical model of dry nanobrushes. These results enable the rational design of responsive surfaces having a tunable topography engineered at the nanometer scale, which is of direct interest for the development of soft nanoactuators and new substrates for cell adhesion studies.     

Classical observations and stable isotopes for identification the diagenesis of Jeribe formation at Jambour oil Fields-Kurdistan Region-Iraq

Jeribe Formation in two subsurface sections were studied using samples from two wells of Jambour oil field, Kirkuk area-northern Iraq to determine its petrographical characteristics, microfacies, depositional environment, and diagenetic signatures based on δ¹⁸O and δ¹³C isotope analysis. Three main types of associated microfacies were detected: mudstone, wackestone, and packestone/grainstone. The inspected formation experienced various diagenetic processes. The well-preserved dolomitization and pressure-solution and stylolitic microstructures bring a new insight in form of the paragenetic sequence. The isotopic signature data revealed that the positive covariance of ¹⁸O and ¹³C isotopes is closely associated with infiltration of meteoric water during the mesogenesis.     

Sur l'existence de phases ternaires hydrogenees BeP2−xHy

The phosphidation of beryllium in the presence of traces of hydrogen leads to non stoichiometric ternary phases BeP_2?xH_y. The stoichiometric diphosphide BeP₂ cannot be obtained. The hydrogenated phases are black and non hygroscopic. The structural study with X rays diffraction, neutrons diffraction, electronic microdiffraction, as well as the crystallographic data from single crystal, provide evidence for a quadratic cell with $\text{a}\text{= 7,08}\text{A}\text{?}$ & $\text{c}\text{= 30,12}\text{A}\text{?}$. The stacking is diamond type when considering all the atoms : Be, P and H.     

Pressure correction DRBEM solution for heat transfer and fluid flow in incompressible viscous fluids

The Dual Reciprocity Boundary Element Method (DRBEM) is used to solve incompressible laminar viscous fluid flows and heat transfer. The DRBEM is extended to develop a pressure correction scheme to solve the incompressible Navier-Stokes equations. The velocity field is then used as input to the DRBEM solution of the energy transport equation, thereby retaining the boundary only discretization feature of the BEM for the solution of this problem. Numerical results for the proposed DRBEM solution for laminar flow and heat transfer in a channel are obtained for several Reynolds numbers and compare well with previously published data.     

Etude comparee de la conductivite ionique du lithium dans les halogenoborates vitreux

New vitreous electrolytes with fast lithium ion carriers have been obtained in the B₂O₃Li₂OLiX (X = F, Cl, Br, I) systems. The variation of the ionic conductivity is discussed as a function of Li₂O and LiX concentration. The choice of the halogen is taken in consideration.