Application of mass spectrometry to the study of fluoropolymers. III. Polyperfluorobut-2-yne

Mass spectra of the volatile fractions from polyperfluorobut-2-yne have been obtained. The polymer appears to be thermally stable up to 300°C and molecules containing up to 12 monomer units have been identified. A regular structure is indicated by the mass spectrum which is characterized by unusually intense doubly charged ions. The endgroups are readily identified, and a conjugated polyolefin structure is indicated.     

Search for the Dirac monopole by means of vavilov-cherenkov radiation at the 70 Gev IHEP (Institute for High Energy Physics Serpukhov) proton synchrotron

At the proton energy of 70 GeV on the internal target of the IHEP proton synchrotron the search was made for magnetic charges over the Vavilov-Cherenkov radiation and characteristic polarization. Eight Cherenkov counters of a special construction served as detectors. Possible events were recorded with two fast five-ray oscillographs triggered by 6-fold coincidences. The efficiency of the magnetic charge recording was about 10%.The proton beam of 6.4×10¹⁴ intensity traversed the target-radiator; and not a single case of the production of the Dirac monopole with the magnetic charge from minimal one of about 2/3g _D (g _D =68.5e) up to2g _D was recorded. This means that in the conditions of our experiment the upper boundary of the cross section of the Dirac monopole production by 70 GeV protons per nucleon of Si and O nuclei for magnetic charges of masses from 3 up to 5·5m_p was found to be(95%) 10^–40 cm².On leave fromDepartment of Nuclear Physics, Comenius University, Bratislava, Czechoslovakia.The authors express their gratitude to the workers of the enterprise Dioptra (Turnov, SSR) for making of optical details for the device for SDM.     

Recent progress on first-principles simulations of voltammograms

In this review article, we provide a brief summary of recent models and applications using first-principles methods to simulate cyclic voltammograms and linear sweep voltammograms. Electrochemical processes considered include hydrogen/hydroxyl adsorption, higher order anion adsorption, and electrocatalytic reactions. Reasonable agreement between experiment and theory is achieved in most systems, and we discuss approximations used and routes for improving the predictive power and accuracy of simulated voltammograms.     

1.1 Grundlagen, Methoden, Apparate, Reagentien, Automation, Datenverabreitung

Ohne Zusammenfassung     

The new element 112

The new element 112 was produced and identified unambiguously in an experiment at SHIP, GSI Darmstadt. Two decay chains of the isotope²⁷⁷112 were observed in irradiations of²⁰⁸Pb targets with⁷⁰Zn projectiles of 344 MeV kinetic energy. The isotope decays by emission of α particles with a half-life of (240 _?90 ⁺⁴³⁰ )µs. Two different α energies of (11,649±20) keV and (11,454±20) keV were measured for the two observed decays. The cross-section measured in three weeks of irradiations is (1.0 _?0.4 ^+1.8 ) pb.     

The calibration of activated charcoal detectors in a small Rn exposure chamber

Passive methods for radon measurements, especially those based on radon adsorption, require observation of proper calibration methods.

The calibration method for diffusion-barrier charcoal detectors in a small (211 dm³) radon chamber has been proposed. The theoretical dependence of radon concentration vs. time inside the chamber during the exposure of charcoal detectors has been obtained and verified experimentally. For this purpose, the chamber volume as well as diffusion and adsorption parameters of the detector were taken into consideration.

For two types of detectors the conformity of calibration factors obtained in two ways: calculated from theoretical points (550 or 683 Bqm⁻³/cps depending on detector type) and from experimental points (553 or 691 Bqm⁻³/cps), was achieved.

The proposed method makes it possible to calibrate different kinds of radon-adsorbing detectors (not only charcoal canisters) in small chambers without the necessity of using any reference, active device.     

Determination and Removal of Selected Pharmaceuticals and Total Organic Carbon from Surface Water by Aluminum Chlorohydrate Coagulant

In the present research, the removal of Total Organic Carbon (TOC) and erythromycin (ERY), fluoxetine (FLX), amoxicillin (AMO), colistin (COL), ethynylestradiol (EE), and diclofenac (DIC) from surface water by coagulation is studied. The concentration of selected pharmaceuticals in 24 surface water samples originating from some rivers located in Lesser Poland Voivodeship and Silesia Voivodeship, Poland, was determined. The removal of TOC and pharmaceuticals was carried out using the application of Design of Experiments (DOE), Response Surface Methodology (RSM), and by addition of aluminum chlorohydrate (ACH) as a coagulant. The study found that the concentration ranges of ERY, FLX, AMO, COL, EE, and DIC in analyzed water samples were 7.58–412.32, 1.21–72.52, 1.22–68.55, 1.28–32.01, 5.36–45.56, 2.20–182.22 ng/L, respectively. In some cases, concentrations lower than 1 ng/L were determined. In optimal conditions of coagulation process of spiked surface water (pH = 6.5 ± 0.1, ACH dose = 0.35 mL/L, Time = 30 min; R² = 0.8799, R²_adj = 0.7998), the concentration of TOC, ERY, FLX, AMO, COL, EE, and DIC was decreased by 88.7, 36.4, 24.7, 29.0, 25.5, 35.4, 30.4%, respectively. Simultaneously, turbidity, color, Total Suspended Solids (TSS), Chemical Oxygen Demand (COD), Total Nitrogen (Total N), and Ammonium-Nitrogen (N-NH₄) were decreased by 96.2%, >98.0%, 97.8%, 70.0%, 88.7%, 37.5%, respectively. These findings suggest that ACH may be an optional reagent to remove studied pharmaceuticals from contaminated water.     

Five loop Konishi from AdS/CFT

We derive the perturbative five loop anomalous dimension of the Konishi operator in N=4$N=4$ SYM theory from the integrable string sigma model by evaluating finite size effects using Lüscher formulas adapted to multimagnon states at weak coupling. In addition, we derive the five loop wrapping contribution for the L=2$L=2$ single impurity state in the β deformed theory, which may be within reach of a direct perturbative computation. The Konishi expression exhibits two new features — a modification of Asymptotic Bethe Ansatz quantization and sensitiveness to an infinite set of coefficients of the BES/BHL dressing phase. The result satisfies nontrivial self-consistency conditions — simple transcendentality structure and cancellation of μ-term poles. It may be a testing ground for the proposed AdS/CFT TBA systems.     

Relationship between wine scores and visible–near-infrared spectra of Australian red wines

Sensory analysis of wine involves the measurement, interpretation and understanding of human responses to the properties perceived by the senses such as sight, smell and taste. The sensory evaluation of wine is often carried out by wine judges, winemakers and technical staff, and allows characterization of the quality of the wine. However, this method is lengthy, expensive, and its results depend on panel training and the specific vocabulary used by the panel. A robust, rapid, unbiased and inexpensive method to assist in quality assessment purposes will therefore be beneficial for the modern wine industry. This study aims to investigate the relationship between sensory analysis, visible (VIS) and near-infrared (NIR) spectroscopy to assess sensory properties of commercial Australian wine varieties. For the purposes of this study 118 red wine samples (Cabernet Sauvignon, Shiraz, Pinot Noir, Tempranillo, Nebbiolo and blends) graded by a panel of experienced tasters and scored according to the Australian wine show system were scanned in transmission in the VIS and NIR range (400–2,500nm). Partial least squares regression models were developed between the overall score given by the judges and the combined VIS–NIR spectra, using full cross validation (leave-one-out method). The results showed that NIR spectroscopy was able to predict wine quality scores in red wine samples (R = 0.61 and standard error of prediction of 0.81). The practical implication of this study is that instrumental methods such as VIS–NIR spectroscopy can be used to complement sensory analysis and can facilitate the task at early stages of product development, making high-throughput screening of novel products feasible or maintaining the consistency of the product.