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Measuring the shape of the Higgs boson potential is of paramount importance, and will be a challenging task at current as well as future colliders. While the expectations for the measurement of the trilinear Higgs self-coupling are rather promising, an accurate measurement of the quartic self-coupling interaction is presently considered extremely challenging even at a future 100 TeV proton-proton collider. In this work we explore the sensitivity that a muon collider with a center of mass energy in the multi-TeV range and luminosities of the order of 1035cm−2s−1, as presently under discussion, might provide, thanks to a rather large three Higgs-boson production and to a limited background. By performing a first and simple analysis, we find a clear indication that a muon collider could provide a determination of the quartic Higgs self-coupling that is significantly better than what is currently considered attainable at other future colliders. [ABSTRACT FROM AUTHOR]

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Model polymer poly(vinyl acetate) (PVAc) was combined with melamine isocyanurate (MIC) as intumescent flame retardant composite. This work emphasises on the study of the decomposition mechanism and compared with a single fire test in order to show its performance as flame retarded composite. As such, mass loss cone calorimetry tests were performed and compared with it inert and oxidative decompositions in lab tests. PVAc/MIC composites cannot be ignited with high loadings MIC. Difference curves in oxidative conditions revealed that the composites with MIC show only positive differences, indicating a high stabilisation, especially in the temperature region of a mild flame (500-700 °C). Experiments performed with TG coupled with mass spectroscopy and analyses on partially degraded residues with solid-state C-NMR enabled the construction of the complete decomposition mechanism. MIC has both a heat-sink FR activity as well as a crosslinking role in the stabilization of the polymer. The latter then creates a highly stabilised char at elevated temperatures in oxidative environments. The formed char starts to degrade only 100 °C higher than the pure polymer within a heating. The degradation of formed char of pure PVAc is autocatalytic; this behaviour disappears upon addition of sufficient amount of MIC. Therefore, the transport of fuel towards the gaseous phase is limited, creating an efficient flame retardant system. [ABSTRACT FROM AUTHOR]

A self-healing material for coating applications was synthesized using the Diels-Alder (DA) reaction as cross-linking reaction. The built-in reversibility allows local mobility and rearrangements in the polymeric network, which is composed of a furan functionalized epoxy-amine and a bismaleimide. The self-healing material was characterized by physical-chemical means using Fourier Transform Infrared spectroscopy, thermogravimetric analysis (TG) and rapid heat-cool differential scanning calorimetry. It has been shown that the reversibility, as a result of a change in DA/retro-DA equilibrium, occurs in a temperature window ranging from ca. 80 to 150 °C. The repeatability of the non-autonomous healing was checked by TG, showing no evaporation or degradation of the components involved in the temperature window of interest. [ABSTRACT FROM AUTHOR]

In this paper we compare Wollaston and silicon probes for localized thermal analysis measurements (LTA) on biaxially oriented polypropylene (BOPP) films. Up till now, no real comparison was reported in literature between the different transition temperatures measured using Wollaston and silicon probes. Using different types of probes for studying the same material proves to be very interesting. Using the Wollaston probe, the thermal properties and thickness of a 1 μm thick skin layer can be determined by through-thickness local thermal analysis measurements. The improved resolution of the silicon probes, enables the measurement of thermal properties of individual layers in a cross-sectioned film, even for layers of only 1 μm thickness. Based on the results, the silicon probes seem to be more sensitive toward the start of the melting process, since the silicon probe already penetrates at lower temperature, as compared to the Wollaston probes. This sensitivity can be exploited for studying the effect of variations in thermal history between or within samples. [ABSTRACT FROM AUTHOR]

The reaction of phosphoric acid with wollastonite has been studied for reaction mixtures with a molar ratio r=P/Ca from 0.39 up to 2.9. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) reveal the formation of the crystalline products brushite (when r is smaller than 1.4) and monetite and calcium dihydrogenphosphate monohydrate (when r is above 1). Magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) and FTIR show that amorphous silica is also formed which contains some residual calcium and hydroxyl groups. The proposed reactions are confirmed by the evolution of the reaction enthalpy measured with differential scanning calorimetry (DSC). The reaction was monitored with temperature modulated DSC (TMDSC) and dynamic mechanical analysis (DMA). The sharp increase of the elasticity modulus coincides with the onset of decrease in heat capacity. The setting of the reaction mixture does not slow down the reaction rate. [ABSTRACT FROM AUTHOR]

The reaction kinetics and mechanism of geopolymers are studied. The dissolved silicate concentration decreases from the beginning of the reaction. A characteristic time ‘ t 0,vit’ for the setting of the reaction mixture is derived from isothermal Dynamic Mechanical Analysis experiments. ‘ t 0,vit’ increases with SiO2/R2O but goes through a minimum for increasing water content. The reaction is slower for K compared to Na-silicate based systems. 29Si and 27Al solution NMR are used to probe the molecular changes. 27Al NMR and FTIR reveal that an ‘intermediate aluminosilicate species’ (IAS) is formed from the start of the reaction. The concentration decrease of OH− during low-temperature reaction is related to the formation of IAS. The rate law of this process seems to be obeyed by a total reaction order of 5/3, with a partial order of 1 for OH− and 0 for Na+ in the silicate solution. During first heating after polymerization water is lost leading to a distortion of the Al environment. According to XRD, no crystallization occurs below 900 °C. However, between 950 and 1100 °C a crystallization exotherm of nepheline is observed with DSC for a geopolymer with SiO2/Na2O = 1.4. Neither T g of the amorphous geopolymer, nor the shrinkage and expansion around T g during first heating, cause a measurable heat effect. [ABSTRACT FROM AUTHOR]

In the minimal supersymmetric standard model (MSSM), we study the light Higgs boson radiation off a light-chargino pair in the process $ e^{ + } e ^{-} \to h\tilde{\chi }^{ + }_{1} \tilde{\chi }^{ - }_{1} $ at linear colliders with $ {\sqrt s } = 500\;{\text{Gev}} $ GeV. We analyze cross sections in the regions of the MSSM parameter space where the process $ e^{ + } e ^{-} \to h\tilde{\chi }^{ + }_{1} \tilde{\chi }^{ - }_{1} $ cannot proceed via on-shell production and subsequent decay of either heavier charginos or the pseudoscalar Higgs boson A. Cross sections up to a few fb are allowed, according to present experimental limits on the Higgs boson, chargino and sneutrino masses. We also show how a measurement of the $ e^{ + } e ^{-} \to h\tilde{\chi }^{ + }_{1} \tilde{\chi }^{ - }_{1} $ production rate could provide a determination of the Higgs boson couplings to charginos. [ABSTRACT FROM AUTHOR]

The effect of the particle size of metakaolinite on the reaction kinetics of low-temperature synthesized inorganic polymer glasses is studied. The heat capacity of the material during isothermal cure is measured by Modulated DSC (MDSC). This signal can be followed quantitatively during the complete course of the reaction, whereas the heat flow signal is sometimes too small for quantitative interpretations. A characteristic time for the reaction, defined as onset of vitrification, is also measured with Dynamic Mechanical Analysis (DMA). The DMA and MDSC results show that the reaction rate increases with decreasing particle size of metakaolinite, at least till a particle size of about 2 μm. It can be concluded that the first step of the reaction, breaking down the metakaolinite grains, occurs at the surface of the particles. The second step is the building of a network starting from the reaction products of the former reaction. [ABSTRACT FROM AUTHOR]

The degree of dehydroxylation of kaolinite, DTG and DIR, respectively, is characterized by thermogravimetric analysis (TG) and Fourier transform infrared spectroscopy (FTIR). The relation between DTG and DIR based on the infrared absorptions at 3600–3700, 915, 810, and 540 cm−1 is established. Three regions can clearly be distinguished: the dehydroxylation region (DTG<0.9), the metakaolinite region (0.9TG<1) and the ‘spinel’ region(DTG=1). The effect of the degree of dehydroxylation of kaolinite on the amount of reactive material is measured by the reaction enthalpy, Δ H, of the low-temperature reaction of the dehydroxylated kaolinite with a potassium silicate solution using differential scanning calorimetry (DSC). |Δ H| increases almost linearly with DTG in the dehydroxylation region. In the metakaolinite region, Δ H and thus the amount of reactive material, becomes constant. |Δ H| is sharply decreasing when metakaolinite transforms into other phases in the ‘spinel’ region. No significant differences in the reactivity of the dehydroxylates is detected with DSC. According to FTIR, the use of partially dehydroxylated kaolinite is not influencing the molecular structure of the low-temperature synthesized aluminosilicates, but residual kaolinite is retrieved as an additive. [ABSTRACT FROM AUTHOR]

The free radical cross-linking copolymerization of an unsaturated polyester resin with styrene is studied in isothermal conditions using temperature modulated differential scanning calorimetry (TMDSC) and dynamic rheometry. The dynamic rheometry measurements show that gelation occurs at a conversion below 5%, while TMDSC measurements show that an important autoacceleration starts near 60% conversion, giving rise to a maximum cure rate closely before the (partial) vitrification of the system near 80%. This indicates that the autoacceleration is not due to the sharp increase in bulk viscosity at gelation, but rather to a change in molecular mobilities at higher conversion. [ABSTRACT FROM AUTHOR]

Modulated temperature differential scanning calorimetry (MTDSC) is used to study simultaneously the evolution of heat flow and heat capacity for the isothermal and non-isothermal cure of an epoxy-anhydride thermosetting system. Modelling of the (heat flow related) chemical kinetics and the (heat capacity related) mobility factor contributes to a quantitative construction of Temperature-Time-Transformation (TTT) and Continuous-Heating-Transformation (CHT) diagrams for the thermosetting system. [ABSTRACT FROM AUTHOR]

The influence of temperature modulation and signal treatment (deconvolution procedure) of modulated temperature differential scanning calorimetry is discussed with respect to the investigation of cure kinetics of thermosetting systems. The use of a ‘dynamic’ heat capacity calibration is not important for this purpose due to normalization of the heat capacity signal in all cure experiments. The heat flow phase during isothermal and non-isothermal cure is always small, giving rise to negligible corrections on the heat capacity and reversing heat flow signals in-phase with the modulated heating rate. The evolution of the heat flow phase contains information on relaxation phenomena in the course of the chemical reactions. [ABSTRACT FROM AUTHOR]

The low-temperature reaction between an aqueous sodium or potassium silicate solution and metakaolinite yields a solid aluminosilicate. The influence of the molar ratios H2O/R2O (between 6.6 and 21.0) and SiO2/R2O (between 0.0 and 2.3) of the silicate solution (R=Na or K) on the aluminosilicate's production, on the reaction stoichiometry and on the aluminosilicate's molecular structure is studied with differential scanning calorimetry, 27Al and 29Si magic angle spinning nuclear magnetic resonance (MAS NMR), cross-polarization MAS NMR, Fourier transform infrared spectroscopy and X-ray diffractometry. The reaction stoichiometry is determined by a one to one ratio for R/Al. H2O/R2O has no influence on the molecular structure of the aluminosilicate. Aluminium in the aluminosilicate is four-fold coordinated for the whole range of silicate solutions investigated. Moreover, Si and Al are homogeneously distributed and the ratio Al/Si in the aluminosilicate is the same as in the reaction mixture if the stoichiometric one-to-one ratio for R/Al is used. If SiO2/R2O in the Na-silicate solution is equal to or higher than 0.8, the low-temperature reaction yields an amorphous aluminosilicate or “inorganic polymer glass”. For smaller values of SiO2/R2O the Na-aluminosilicates are partially crystalline. Thermomechanical analysis and dynamic mechanical analysis indicate that a variation in the composition of the amorphous aluminosilicates can shift the glass transition over a few hundreds of degrees, with a minimum value of 650°C. [ABSTRACT FROM AUTHOR]

Present limits on the top mass from LEP1 and Tevatron point to a top quark that is considerably heavier than the W vector boson in the standard model; e e colliders with $$\sqrt s \simeq 300$$ GeV (the c.m. energy foreseen at the first phase of the next linear e e collider) could be well below the energy threshold for real top-pair production. We argue that, if this is the case, single top production through the process $$e^ + e^ - \to t\bar bW^ - (\bar tbW^ + )$$ , where $$t\bar b(\bar tb)$$ are produced mainly by means of a virtual W, becomes the dominant top production mechanism. Total cross sections and kinematical distributions are evaluated and numerical results are given in ranges of m and $$\sqrt s $$ where single top production can be of relevance. The relative importance of virtual- W and virtual- t contributions to the process is discussed. [ABSTRACT FROM AUTHOR]

Production and detection of new heavy vector bosons is studied at present (or near future) p $$\bar p$$ collider experiments. Application to CERN and Tevatron experiments is considered in detail, but some results for the UNK p $$\bar p$$ collider, at $$\sqrt s $$ = 6TeV, are also presented. Rather than considering a number of detailed models, we prefer to discuss some general, although necessarily schematic, classes of new vector bosons ranging from strongly interacting Higgs sector models to extended gauge models. We study in particular signals and backgrounds in the $$\ell \overline \ell jj$$ channels, where ℓ are leptons and j are hadron jets. [ABSTRACT FROM AUTHOR]

A girl with slight psychomotor retardation, microphthalmia, and colobomata of the left eye, a hypotrophy of the right arm and a surnumerary digit on the right hand is described. The routine chromsome analysis and a G-banding analysis revealed an elongated long arm of chromosome 10. An extra light and dark band was present proximally. Both parents had normal chromosomes. While the visual comparison of the abnormal with the normal chromosome 10, did not enable the extra bands of the normal bands q21 and q22 to be distinguished. However, measurements of length, surface area, and relative reflection of the different light and dark bands of the long arm on tracings or directly on the normal and abnormal chromosomes, enabled us to precisely locate the extra bands and to determine that the abnormal chromosome was a result of an insertional translocation. The value of such measurements is discussed. [ABSTRACT FROM AUTHOR]