Linear Response Calculations of Lattice Dynamics in Strongly Correlated Systems

We introduce a new linear response method to study the lattice dynamics of materials with strong correlations. It is based on a combination of dynamical mean field theory of strongly correlated electrons and the local density functional theory of electronic structure of solids. We apply the method to study the phonon dispersions of a prototype Mott insulator NiO. Our results show overall much better agreement with experiment than the corresponding local density predictions.Comment: 4 pages, 2 figure

Endoscopic full-thickness resection of T1 colorectal cancers:a retrospective analysis from a multicenter Dutch eFTR registry

Background Complete endoscopic resection and accurate histological evaluation for T1 colorectal cancer (CRC) are critical in determining subsequent treatment. Endoscopic full-thickness resection (eFTR) is a new treatment option for T1 CRC<2cm. We aimed to report clinical outcomes and short-term results. Methods Consecutive eFTR procedures for T1 CRC, prospectively recorded in our national registry between November 2015 and April 2020, were retrospectively analyzed. Primary outcomes were technical success and R0 resection. Secondary outcomes were histological risk assessment, curative resection, adverse events, and short-term outcomes. Results We included 330 procedures: 132 primary resections and 198 secondary scar resections after incomplete T1 CRC resection. Overall technical success, R0 resection, and curative resection rates were 87.0% (95% confidence interval [CI] 82.7%-90.3%), 85.6% (95%CI 81.2%-89.2%), and 60.3% (95%CI 54.7%-65.7%). Curative resection rate was 23.7% (95%CI 15.9%-33.6%) for primary resection of T1 CRC and 60.8% (95%CI 50.4%-70.4%) after excluding deep submucosal invasion as a risk factor. Risk stratification was possible in 99.3%. The severe adverse event rate was 2.2%. Additional oncological surgery was performed in 49/320 (15.3%), with residual cancer in 11/49 (22.4%). Endoscopic follow-up was available in 200/242 (82.6%), with a median of 4 months and residual cancer in 1 (0.5%) following an incomplete resection. Conclusions eFTR is relatively safe and effective for resection of small T1 CRC, both as primary and secondary treatment. eFTR can expand endoscopic treatment options for T1 CRC and could help to reduce surgical overtreatment. Future studies should focus on long-term outcomes

Energy for grinding aluminium oxide

An experimental investigation of material removal from four aluminium oxide ceramics by a single point diamond tool was conducted. A kinetic model was constructed and the specific grinding energy was determined for a variety of grinding conditions. © 1979, Taylor & Francis Group, LLC

Wear of diamond particles for grinding ceramics

The relative wear of a single point diamond, defined in terms of the grinding force, was determined for a group of A12O3and Si3N4. It was found that the wear rate is directly related to the mechanical properties of the workpiece and the grinding environment. © 1984 Taylor & Francis Group, LLC

Interprétation du durcissement de la solution solide à l'aide de spectres vibrationnels.

peer reviewedSolid solution hardening has been reviewed with respect to existing experimental data. It is shown with the aid of new experimental data on two inorganic systems (NiO-CoO and CaF(2)-SrF(2)) that the large increase in hardness of intermediate compositions correlates qualitatively and can also be quantitatively justified by the use of selected values of the parameters in a previously developed atomistic hardness formula. The key parameters are the variations in the unit cell dimensions, the eigenfrequency, and anharmonic factor of the structure

Raman spectra of AℓN, cubic BN and BP

Raman spectra of wurtzite AℓN and zincblende BN and BP were excited by a He-Ne laser (6328A). The long wavelength Raman lines determined are the following: (i) For AℓN A1 (TO) = E1(TO) = 667 cm-1, A1 (LO) = E1 (LO) = 910 cm-1 and E2 = 665 cm-1; (ii) For cubic BN TO = 1056 cm-1 and LO = 1304 cm-1; (iii) For BP only one line was observed at 829 cm-1. The ratio of LO to TO intensities is discussed briefly. © 1968