Thick metric spaces,relative hyperbolicity,and quasi-isometric rigidity

We study the geometry of non-relatively hyperbolic groups. Generalizing a result of Schwartz, any quasi-isometric image of a non-relatively hyperbolic space in a relatively hyperbolic space is contained in a bounded neighborhood of a single peripheral subgroup. This implies that a group being relatively hyperbolic with non-relatively hyperbolic peripheral subgroups is a quasi-isometry invariant. As an application, Artin groups are relatively hyperbolic if and only if freely decomposable. We also introduce a new quasi-isometry invariant of metric spaces called metrically thick, which is sufficient for a metric space to be non-hyperbolic relative to any non-trivial collection of subsets. Thick finitely generated groups include: mapping class groups of most surfaces; outer automorphism groups of most free groups; certain Artin groups; and others. Non-uniform lattices in higher rank semisimple Lie groups are thick and hence non-relatively hyperbolic, in contrast with rank one which provided the motivating examples of relatively hyperbolic groups. Mapping class groups are the first examples of non-relatively hyperbolic groups having cut points in any asymptotic cone, resolving several questions of Drutu and Sapir about the structure of relatively hyperbolic groups. Outside of group theory, Teichmüller spaces for surfaces of sufficiently large complexity are thick with respect to the Weil–Peterson metric, in contrast with Brock–Farb’s hyperbolicity result in low complexity.     

Analytical methods to differentiate Romanian amber and Baltic amber for archaeological applications

The study aims to establish several definite criteria which will differentiate Romanian amber and Baltic amber to certify the local or Baltic origin of the materials found in archaeological sites on the Romanian territory, by using light microscopy and performing analytical methods, such as Fourier transform infrared spectroscopy-variable angle reflectance and liquid chromatography with mass spectrometry detection. Experiments especially by Fourier transformed infrared spectroscopy, were applied to a wide range of samples with controlled origin. The methods were optimised and resulted in premises to apply the techniques to analysis of the archaeological material.      

Measurements of the angular distributions of muons from Υ decays in pp collisions at sqrt[s] = 1.96 TeV

The angular distributions of muons from Υ(1S,2S,3S) → μ+ μ- decays are measured using data from pp collisions at sqrt[s] = 1.96 TeV corresponding to an integrated luminosity of 6.7 fb(-1) and collected with the CDF II detector at the Fermilab Tevatron. This analysis is the first to report the full angular distributions as functions of transverse momentum p(T) for Υ mesons in both the Collins-Soper and s-channel helicity frames. This is also the first measurement of the spin alignment of Υ(3S) mesons. Within the kinematic range of Υ rapidity |y|<0.6 and p(T) up to 40 GeV/c, the angular distributions are found to be nearly isotropic.     

Measurement of ZZ production in leptonic final states at sqrt[s] of 1.96 TeV at CDF

In this Letter, we present a precise measurement of the total ZZ production cross section in pp collisions at sqrt[s]=1.96 TeV, using data collected with the CDF II detector corresponding to an integrated luminosity of approximately 6 fb(-1). The result is obtained by combining separate measurements in the four-charged (???' ?') and two-charged-lepton and two-neutral-lepton (??νν) decay modes of the Z boson pair. The combined measured cross section for pp → ZZ is 1.64(-0.38)(+0.44) pb. This is the most precise measurement of the ZZ production cross section in 1.96 TeV pp collisions to date.     

清炒枇杷叶中9种元素的测定

采用火焰原子吸收光谱法(FAAS)测定清炒枇杷叶中Fe、Cu、Mg、Ca、Mn、Zn、Ni、Cr、Pb 9种金属元素的含量。结果表明,9种元素的质量浓度在一定范围内均与其峰面积呈线性关系。该法用于清炒枇杷叶样品分析,9种元素测定值的相对标准偏差均小于3%(n=6),标准加入法测得9种元素回收率在95.7%—105.0%之间。采用火焰原子吸收光谱法测定清炒枇杷叶中9种元素稳定性好,结果准确可靠。     

Bulk and surface properties of blends with semifluorinated polymers and block copolymers

The goal of the investigation presented here is the development of extremely hydrophobic materials based on polysulfone that can be applied, for instance, as fouling-resistant membrane materials. The concept used is the addition of semifluorinated polymers to polysulfone in suitable blend compositions. The influence of molecular parameters like chain structure of the semifluorinated polymer (segmented block copolymers, random copolymers) and segment molecular weight on the state of phase separation in the bulk and its influence on the surface properties have been systematically examined. It could be shown that segmented block copolymers with semifluorinated polyester segments with intermediate segment molecular weight are more suitable in blends with polysulfone than random polysulfone copolymers having semifluorinated side chains with respect to form homogeneous thin films (coatings) with highly non-wetting properties.     

Potential of AMnO3 (A=Ca,Sr, Ba,La) as Active Layer in Inorganic Perovskite Solar Cells

Inorganic perovskite CaMnOuot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0001&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/a0436189-f403-44e5-b2a9-011a0815af60/cphc202200837-math-0001.png&quot;> was proposed as a substitution for the TiOuot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0002&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/9eca0ff3-e079-499e-a397-38b15a8d2292/cphc202200837-math-0002.png&quot;> anatase in electron transport layers of solar cells containing the hybrid perovskite CHuot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0003&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/caabf6a8-ee5b-41e2-8db5-0ea9a72e5e69/cphc202200837-math-0003.png&quot;> NHuot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0004&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/ef40ae97-ca89-4284-b1c1-24fbc5632cda/cphc202200837-math-0004.png&quot;> PbIuot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0005&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/20f0056c-d486-41cb-89fe-de02b774f78e/cphc202200837-math-0005.png&quot;> based on increased mobility of electrons and better optical matching. Due to a suitable band gap concerning the absorption of sunlight, we investigate the potential of CaMnOuot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0006&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/de746d87-e3fa-44e5-8251-b2cde90db2ab/cphc202200837-math-0006.png&quot;> and similar manganite perovskites, where Ca is replaced by either Sr, Ba or La, as an absorber layer in inorganic perovskite solar cells. In this study, we have used optical measurements on the synthesized AMnOuot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0007&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/c95c78dc-62ec-44eb-9db5-f5e62f6a14e9/cphc202200837-math-0007.png&quot;> (A=Ca, Sr, Ba, La) samples to aid density functional theory calculations (DFT) in order to accurately simulate the electronic and optical properties of AMnOuot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0008&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/2812fdac-372b-4887-ad6b-1c23c7f9551b/cphc202200837-math-0008.png&quot;> compounds and gauge their potential for the role of absorber layer. Both experimental measurements and theoretical calculations show suitable band gap of 1.1-1.5 eV, depending on the compound, and absorption coefficients of the order of uot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0009&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/df8826fd-511e-4bd1-baa9-1b1a26e7e573/cphc202200837-math-0009.png&quot;> cmuot;urn:x-wiley:14394235:media:cphc202200837:cphc202200837-math-0010&quot; loading=&quot;lazy&quot; class=&quot;section_image&quot; src=&quot;/cms/asset/41d06b3c-2991-4352-8b26-12d5066c1e3d/cphc202200837-math-0010.png&quot;> in the visible part of the spectrum.