Réveil, réincarnation et restitution : Yves Bonnefoy dans l’Imaginaire musical de Jeremy Thurlow

The substitution or addition of new supplementary cementitious materials (SCM) in the production of variety of construction materials has gained much interest. One of the examples of SCM is incineration ash which consist of fly ash (FA) and bottom ash (BA) which are the residues from the ignition of biomass and can brings applicable ecological advantages. However, the properties of this new materials need to be investigated to ensure its full potential can be developed. Therefore, this study is initiated to identify the characteristics of incineration ash from local source in Malaysia. To identify the elemental components of ashes, most widely method was adopted which is using X-Ray Fluorescence (XRF). The quantity of unburned carbon in fly ash is measured by loss on ignition, which has a major influence on the product’s characteristics. In addition, specific gravity and density were also determined and comparison has been made with cement. In this study it was found out that XRF results shows that both FA and BA consist of the same mineral composition with OPC majorly in silica, aluminium, calcium, and iron which makes is suitable to be used in the concrete. For LOI, the value for BA is much higher compared with FA due to the amount of unburnt carbon in its original compositions and the incomplete burning due to insufficient contact time in the furnace. Based on the result obtained for LOI, the average LOI value for FA and BA is 17.33 % and 44.67 %, respectively. As expected, for the specific gravity and density, FA having the lowest specific gravity and density. The density obtained for FA is 755 kg/m3 and for BA is 593 kg/m3. Overall, the use of incineration ash can be fully investigated by exploring other parameter that influence the performance of construction materials.

The results of experimental studies of sensitive elements of temperature transducers based on semiconductor thermometric material HfNi 1-x Cu x Sn are presented. Thermometric materials HfNi 1-x Cu x Sn, x=0.01-0.10, were produced by fusing a charge of components in an electric arc furnace with a tungsten electrode (cathode) in an atmosphere of purified argon under a pressure of 0.1 kPa on a copper water-cooled base (anode). Heat treatment of the alloys consisted of homogenizing annealing at a temperature of 1073 K. The samples were annealed for 720 hours. in quartz glass ampoules vacuumed to 1.0 Pa in muffle electric furnaces with temperature control with an accuracy of ±10 K. Diffraction data arrays were obtained on a STOE STADI-P powder diffractometer (Cu Kα 1 radiation), and the structural characteristics of HfNi 1-x Cu x Sn were calculated using the Fullprof program. The chemical and phase compositions of the samples were monitored using metallographic analysis (scanning electron microscope Tescan Vega 3 LMU). The thermoelectric pair platinum-thermometric material Pt-HfNi 0.99 Cu 0.01 Sn was the basis of the thermoelectric converter. Modeling of thermometric characteristics of sensitive elements of thermotransducers in the temperature range of 4.2-1000 K was carried out by the full potential linearized plane wave method (Full Potential Linearized Augmented Plane Waves, Elk software package). The results of experimental measurements served as reference currents for modeling characteristics. X-ray phase analysis showed the absence of traces of extraneous phases in the diffractograms of the studied samples of HfNi 1-x Cu x Sn thermometric materials, and the microprobe analysis of the concentration of atoms on their surface established the correspondence to the original composition of the charge. Refinement of the crystal structure of HfNi 1-x Cu x Sn showed that the introduction of Cu atoms orders the structure, which makes it stable, and the kinetic characteristics are reproducible during thermocycling at temperatures T=4.2-1000 K. Ordering the structure of the thermometric material HfNi 1-x Cu x Sn leads to changes in the electronic structure. At the same time, the number of donors decreases -Ni leaves the Hf position, and the substitution of Ni atoms for Cu leads to the generation of structural defects of the donor nature (Cu atoms contain more 3d-electrons), and another donor band ε D Cu will appear in the band gap ε g . For the sensitive elements of thermoconverters at Cu impurity concentrations x=0.005 and x=0.01, the temperature dependences of the specific electrical resistance ln(ρ(1/T)) contain activation areas, which is consistent with the results of electronic structure modeling. This indicates the location of the Fermi level ε F in the band gap ε g , and the negative value of the thermopower coefficient α(T) at these temperatures specifies its position -near the conduction band ε C . The value of the activation energy from the Fermi level ε F to the bottom of the conduction band ε C was calculated. For the base semiconductor n-HfNiSn, the Fermi level ε F lies at a distance of ε F =81 meV from the co ε C conduction band ε C , and in the sensitive elements of thermoconverters with concentrations of HfNi 0.995 Cu 0.005 Sn and HfNi 0.99 Cu 0.01 Sn -at distances of ε F =1 meV and ε F =0.3 meV respectively. Therefore, an increase in the concentration of the Cu donor impurity leads to a rapid movement of the Fermi level ε F to the bottom of the conduction band at a rate of Δε F /Δx≈81 meV/%Cu. The impurity concentration x=0.01 is sufficient for the metallization of the conductivity of sensitive elements of HfNi 1-x Cu x Sn converters at low temperatures. This is possible if the Fermi energy ε F is close to the conduction band ε C (ε F =0.3 meV), which simplifies the thermal ionization of donors and the appearance of a significant number of free electrons. However, this impurity donor zone still does not intersect with the bottom of the conduction band ε C . At concentrations of the Cu donor impurity in HfNi 1-x Cu x Sn, x=0.2-0.07, the high-temperature activation regions disappear on the temperature dependences of the resistivity ln(ρ(1/T,x)), which indicates the movement of the Fermi level ε F from the band gap ε g to the conductivity ε C . At the same time, the values of specific electrical resistance ρ(T,x) increase monotonically with increasing temperature), and the scattering of electrons by phonons determines the conductivity of sensitive elements of thermotransducers based on the thermometric material HfNi 1-x Cu x Sn. The metallization of the electrical conductivity of the thermometric material HfNi 1-x Cu x Sn at concentrations x>0.01 is accompanied by a rapid decrease in the values of the thermopower coefficient α(x, T). Thus, if in n-HfNiSn at a temperature of T=80 K, the value of the thermal erst coefficient was α x=0 =-178 μV/K, then in the HfNi 0.93 Cu 0.07 Sn material α x=0.07 =-24 μV/K. The results of the kinetic properties of HfNi 1-x Cu x Sn are consistent with the conclusions of structural and energetic studies. The simulation of the conversion functions of the sensitive elements of the resistance thermometer and the thermoelectric converter in the temperature range of 4.2-1000 K was carried out. As an example, the conversion functions of the thermoelectric pair Pt-HfNi 0.99 Cu 0.01 Sn are given. The ratio of change of thermo-emf values to the range of temperature measurements in thermocouples is greater than all known industrial thermocouples. However, due to the metallization of the conductivity of the thermometric material HfNi 1-x Cu x Sn, x>0.01, the temperature coefficient of resistance (TCR) of the obtained resistance thermometers is greater than the TCR of metals, but is inferior to the value of TCR of sensitive elements made of semiconductor materials.