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In the framework of the thermochemical energy storage (TCES) for concentrating solar power (CSP) applications, the reversible calcination/carbonation of metal carbonates is receiving increasing interest. In this context, the SrCO3/SrO system is one of the most promising solution due to its high energy density (4 GJ m-3) and working temperatures (up to 1200 °C). In analogy to the well-known CaCO3/CaO system, also SrO suffers from a dramatic drop of reactivity when subjected to cycling operations due to sintering. Therefore, it is necessary to focus the research activity to the material characterization and improvement of its multicycle conversion and stability. In this work, different materials (containing Al, Ca, P or Zr) have been incorporated in the SrO/SrCO3 system as agglomeration/sintering inhibitors. The multi-cyclic stability and performances of all the synthesized SrObased composites have been studied in thermobalance and the materials, have been characterized from the morphological and chemico-physical point of view (SEM-EDS, XRD). [ABSTRACT FROM AUTHOR]

The combustion characteristics of Huadian oil shale and its semicoke are comparatively studied using a thermobalance (TB) and a drop-tube furnace (DTF). It is found that the ignition mechanism of oil shale and semicoke is hetero-homogeneous and heterogeneous, respectively. Drop-tube furnace experiments with both oil shale and semicoke show that the carbon (C) conversion proceeds almost simultaneously with the particle burnout, while the hydrogen (H) conversion is faster and that of nitrogen (N) and sulphur (S) slower than the particle burnout. The kinetic behavior of semicoke combustion is analyzed by drop-tube furnace experiments based on the first-order reaction model, and the kinetic model with known pre-exponential factor Aa (26.3 g·cm-2 s-1·atm-1) and apparent active energy Ea (65.8 kJ/mol) is obtained. [ABSTRACT FROM AUTHOR]

Abstract The surface orientation of crystals has an influence on various material properties, like the oxidation. A method was developed to correlate the oxidation rate for individual single crystal grains with their surface orientation. The surface orientation of many grains of polycrystalline, recrystallized tungsten samples was determined using electron backscatter diffraction. Subsequently, the samples were oxidized in a thermobalance, measuring the time dependent weight increase. The grain dependent oxidation rates were determined by measuring the thickness of the oxide layer for many individual grains with confocal laser scanning microscopy and the scanning electron microscopy on focus ion beam prepared cross-sections. In the temperature range of 720 K to 870 K, tungsten grains with {100} surface orientation have the highest oxidation rate, which is two times higher than the lowest oxidation rate. The lowest oxidation rate belongs to the {111} surfaces orientation, while the {110} surfaces orientation has an intermediated rate. The derived oxidation rates are consistent with gravimetric measurements. They follow an Arrhenius behavior with an activation energy of 190 kJ/mol. Highlights • Method to measure and evaluate orientation of many single crystal grains • Determine the fraction of the oxide layer above and below the original surface level • The oxidation rate vary by a factor of two in temperature range 720 to 870 K [ABSTRACT FROM AUTHOR]

Thermogravimetry coupled with chemometrics has proved to be a rapid and cost-effective diagnostic tool for β-thalassemia screening. This model, consisting of Partial Least Square-Discriminant Analysis (PLS-DA), permitted the discrimination of thalassemic patients and healthy individuals, using thermogravimetric curves of blood samples. In this study, the impact of aspirin on the capability of the TGA/chemometric validated model to screen for thalassemia was investigated. Whole blood samples from patients with congenital defects and healthy individuals were analyzed by the TGA7 thermobalance (Perkin Elmer) without any pretreament, and the resulting curves were compared to those typical of patients after aspirin intake. The chemometric approach allowed a quick identification of the anemia and confirms that the proposed model was not affected by aspirin. Results permit to consider the coupling TGA/chemometrics as a promising diagnostic approach to provide a high-throughput and sensitive tool to obtain an early detection of thalassemia. [ABSTRACT FROM AUTHOR]

Abstract: Alumosilicate minerals are suitable sorbents at high temperatures for removing alkalis in syngas. Thermogravimetric investigations of these sorbents usually focus on the reaction mechanisms. Herein, a crucible arrangement is described that allows evaporation of the alkali source and sorption of gaseous alkali components in one temperature zone. With this experimental setup, kinetic investigations of alkali sorption are possible in a conventional thermobalance. Experiments were performed with sodium chloride as the alkali source and kaolin as the getter material. The reaction rate increased with alkali concentration and showed an exponential dependence on temperature. Thus, the Arrhenius model approach and power law model were selected for mathematical description. [ABSTRACT FROM AUTHOR]

The fast pyrolysis of the juice squeezing derived orange waste has been carried out in a continuous pyrolysis bench-scale plant consisting of a conical spouted bed reactor (CSBR). A prior study performed in thermobalance and a kinetic model consisting of a multi-component mechanism allowed determining the contents of pectin (35 wt%), hemicellulose (16.6 wt%) and cellulose (17.1 wt%), but that of lignin could not be satisfactorily determined as its degradation curve overlapped with other compounds such as sugars, proteins and fats. In the bench scale experiments, the bio-oil yields were very high in the 425–500 °C range (close to 55 wt%) due to the suitable features of the CSBR (high heat and mass transfer rates and short residence time of the volatiles), but they are lower for higher temperatures due to the promotion of secondary cracking reactions. Compared to lignocellulosic biomasses, the orange waste produced a bio-oil with more methanol and furfural and less phenolic species, which is an encouraging fact for its stability and valorization by catalytic cracking or steam reforming. The high concentration of CO 2 in the gas is a drawback for use for energy production. The char yield (33–27 wt%) was high in the whole range of temperatures studied and its high carbon content (71–73 wt%) and HHV (≈27 MJ kg −1 ) are suitable for use as fuel. [ABSTRACT FROM AUTHOR]

The mineralogical-geochemical and thermobarogeochemical features of the Teploe Ag-Au epithermal deposit are considered. The dissolution and redeposition of ore minerals are a result of thermal metamorphism. The redistribution of Ag leads to the formation of lenaite and exsolution structures in minerals of the Cu-Ag-S system; abundant stromeyerite, jalpaite, and mckinstryite compose a significant amount of ores. The atypical physicochemical parameters of the formation of ores include high (for epithermal mineralization) temperatures and low salinity and density of the fluid typical of a dry vapor. The results of fluid inclusion study ascribe the Teploe deposit to an intermediate class of epithermal deposits. [ABSTRACT FROM AUTHOR]

A kinetic study of the oxy-combustion of chars obtained from two Polish steam coals was conducted. A comparative study was focused on the data analysis concerning oxy-combustion of coal chars collected from two thermobalances, which differed in construction, design of crucibles, sample size and gas flow direction. The influence of individual factors such as temperature, O2 concentration, the dimensions of the crucibles and the dimensions of the char bed on the reaction rate was analysed. On the basis of these results, a global kinetic model was elaborated showing the influence of all factors, particularly mass transfer conditions, on reaction rates. The developed model can be extended to other mass transfer conditions or fluidised bed conditions and can be applied to other fast reactions to ensure they occur in the chemical reaction kinetics control regime during TG tests. It was concluded that the gas-solid fuel contact characteristics are crucial for the measured reaction rate and for the interpretation of kinetic data. [ABSTRACT FROM AUTHOR]

Abstract: The thermal degradation kinetics of powder isotactic polypropylene was investigated in a thermobalance system, at non‐isothermal heating conditions with heating rate of 5, 10, 15, and 20°C min−1 in the temperature range of 30–600°C under nitrogen atmosphere. The apparent activation energy (Ea) was determined using Ozawa–Flynn–Wall, Tang Wanjun, and Coats–Redfern (modified) methods. The apparent activation energies range from 61.3 to 110.9 kJ mol−1. Increasing the heating rate shifted the Tmax to a higher level. The lower activation energy observed indicates the breakage of the bonds at weak links. Moreover, the values of activation energy are significantly controlled by the heating rate, level of conversion, and calculation technique. A comparison among the different techniques has been made on the basis of the apparent activation energy from the TG data. The activation energies determined by all the three methods are in good agreement with each other. Furthermore, the pyrolysis of model polypropylene was carried out over the temperature range 350–415°C in a salt bath using Pyrex reaction vessel. The gaseous fraction produced was collected in gas sampling bag and monitored gas chromatographically. The major hydrocarbons detected were methane, propylene, propane, 2‐methylpentane, 2,4 dimethylpentane, and 2,4 dimethylheptane. [ABSTRACT FROM AUTHOR]

Pyrolysis and combustion processes of three Cameroonian biomass have been performed in a thermobalance to determine their thermal degradation profiles and the associated kinetic parameters. The samples were heated from ambient temperature to 900∘C under four low temperature rates (5, 10, 15 and 20∘Cmin-1) and under non-oxidative (nitrogen) or oxidative (synthetic air) atmospheres. The kinetic parameters associated with the pyrolysis of the different samples have been estimated either using a differential isoconversional method with two reaction functions or through the extended independent parallel reaction (EIPR) model and these sets of values are compared. Under nitrogen, the mean values of the activation energies obtained using a differential isoconversional method with Mampel’s reaction function are found equal to 121.2kJmol-1 for oil palm kernel samples, to 158.8kJmol-1 for movingui samples and to 172.5kJmol-1 for padouk samples. When using the 3D diffusion function, the mean value of the activation energies is the same for the two first samples and increases to 178.8kJmol-1 for padouk samples. When applying the EIPR model, the activation energies of the cellulose part (the main part of these lignocellulosic biomass) of the samples are, respectively, equal to 142.5, 155.2 and 149.0kJmol-1 and do not highly vary with the applied temperature ramp. Under air, the values of the kinetic parameters have been determined using the EIPR model and the values of the activation energies slightly vary with the temperature ramp for the three samples. [ABSTRACT FROM AUTHOR]

A mixture of polyethylene (PE), polyethylene-terephtalate (PET), polypropylene (PP) and Nylon was submerged in marine water during 12 moths. The chlorine content of these plastics was measured through the passing time. Thermobalance was used to look for differences in the thermal decomposition of the plastics during in that time interval. Degradation of PET, PP and Nylon produced changes in the weight loss curve, but behaviour of PE is confusing. Pyrolysis and combustion at 850 °C was finally performed to get knowledge of the possible differences in the emission of main gases, volatiles and semivolatiles including polycyclic aromatic hydrocarbons (PAHs), polychlorinated benzenes (ClBzs), polychlorinated phenols (ClPhs), polybrominated phenols (BrPhs), polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Results show that the emission of chlorinated species is somewhat not affected by the chlorine content of the plastics mix. The production of PCBs and PCDD/Fs was very low, under 4 pg WHO-TEQ/g. [ABSTRACT FROM AUTHOR]

Materials chemistry was in its infancy when I started my independent research efforts in India after returning from the United States in the late 1950s. I have investigated phase transformations of TiO2 and CsCl, and also carried out defect calculations. While working on rare-earth oxides, I made TbO2 and PrO2 by a simple solution route; this is probably an early example of chimie douce (soft chemistry). I started working on transition-metal oxides by building simple instruments, including a thermobalance and furnaces. In 1987, we were able to fully characterize the first liquid N2 superconductor (YBa2Cu3O7) using a home-built AC susceptometer. Oxides have been of great interest to me because of the variety of phenomena exhibited by them. I have studied various aspects of transition-metal oxides, including metal-insulator transitions, colossal magnetoresistance, and multiferroics. The last two decades have included research on synthesis, characterization, and properties of various nanomaterials, and in particular, two-dimensional nanosheets (graphene and its inorganic analogues). Two-dimensional sheets and other nanomaterials have been covalently cross-linked to derive new materials with novel properties. Work on water splitting and reduction of CO2, besides using aliovalent anion substitution to generate novel inorganics (Zn2NF in place of ZnO), has also been conducted. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of the temperature and reaction time variables on the solid yield and the increment of heating values and composition of torrefied Dichrostachys cinerea wood by using a factorial experiment design and thermogravimetric analysis. The significant factors were identified by means of a two-level factorial design type (2), for which the statistical software Design Expert version 10 was used. Torrefaction and thermogravimetric experimental runs were carried out in a fixed-bed reactor and thermobalance TGA-DTA, respectively. Torrefaction temperature, residence time and their interaction have a significant effect on solid yield, whilst the effect of the temperature was the only statistically significant factor on increment at a high heating value (HHV). The R-Squared values for both response variables were greater than 95% in each case. An increase in torrefied biomass was achieved at HHVs of 14.92 and 30.31% under the conditions of 120 min at 250 and 290 °C, respectively. Thermogravimetric characterisation and DTG-TG curves of the torrefied material suggest that the pre-treated material has been modified chemically and structurally. [ABSTRACT FROM AUTHOR]

The influence of the pressure and other operating conditions such as particle size, sweep gas flow and initial sample weight on the cellulose pyrolysis process using a bench scale plant high pressure thermobalance was evaluated. The particle size and the sweep gas flow did not have a great influence on the pyrolysis process. Nevertheless, initial sample weight altered the thermochemical behavior of the pyrolysis process. Moreover, a comparison of the values of the kinetic parameters obtained from pyrolysis experiments performed at lab and bench scale was established. On the other hand, the morphology, the presence of functional groups, the surface area, the proximate analysis and elemental analysis of the chars obtained were studied. Moreover, the evolved gases from the pyrolysis performed at different pressures were also analyzed. An increase of pressure led to both a decrease in the temperature at which pyrolysis took place and an increase in the char yield. Furthermore, the higher the pressure, the higher the porosity, the lower the pores size and the higher the occurrence of alkanes and carbonyl components in the resulting chars were. Finally, the gas released analysis from the pyrolysis process by mass spectrometry showed that high pressures promoted the CH 4 and CO 2 formation, the H 2 yield being practically negligible. [ABSTRACT FROM AUTHOR]

Chronic pain in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), NIH category III is difficult to treat without understanding its cause. The main symptom of chronic prostatitis is pain. In this study, we would like to explain the origin of pain in men with CP/CPPS and its therapy. Forty-five patients with CP/CPPS have received thermobalancing therapy (TT) enabled by Dr Allen's therapeutic device (DATD) for six months as mono-therapy. The control group comprised 45 men with CP/CPPS did not receive TT. Before and after six months the National Institute of Health Chronic Prostatitis Symptom Index (NIH-CPSI) scores, prostatic volume (PV) by ultrasound measurement and uroflowmetry (Qmax) were compared between the groups. Baseline characteristics have shown no difference. After TT, significant improvements in pain score (p < 0.001), quality of life index (QoL) (p < 0.001), decrease of PV (p < 0.001), and increase Qmax (p < 0.001) were determined. There were not noteworthy changes in the control group. Chronic pain due to CP/CPPS happens as a consequence and challenges at the capillary level, namely pathological capillary activity. In response to initial triggers--such as inflammation, cold, psychological and other factors--constriction and spontaneous expansion of capillaries follows, creating a continuous secondary trigger--i.e., the micro-focus of hypothermia--which in turn provokes expansion of capillaries. The additional tissue due to vascular changes into the prostate increases pressure on nociceptors causing pain. TT relieves chronic pelvic pain by eliminating the lasting focus of hypothermia in the affected prostate tissue. [ABSTRACT FROM AUTHOR]

The catalytic effect of iron oxide on the oxidation kinetics of synthetic char was investigated in a fixed-bed reactor and in a conventional thermobalance for comparison. Synthetic char doped with iron oxide was obtained by pyrolyzing hydrochar at 800 °C, which had been synthesized by hydrothermal carbonization of cellulose in the presence of iron oxide. Isothermal char oxidation in the fixed-bed reactor resulted in the most reliable kinetic results. According to model-free kinetic analysis of these experiments at 15% conversion, iron oxide decreased the activation energy of char oxidation from 149 kJ/mol to 133 kJ/mol. Modeling of the conversion-time curves was first performed by using the uniform reaction model and then improved by using a n -th order power law. In the temperature range of 440–490 °C a very good agreement with the experimental data was achieved using n = 0.6. Activation energies amounting to 149 kJ/mol and 134 kJ/mol were derived for the undoped and iron oxide-doped char, respectively, well in line with the model-free analysis. [ABSTRACT FROM AUTHOR]

Magnetic fluids are the colloidal solutions containing suspended magnetic nanoparticles in carrier fluids. The present work analyzed the heat transfer characteristics of de-ionized water and transformer oil (base fluids) based cobalt manganese ferrite (Co1-xMnxFe2O3 coated with oleic acid synthesized via co-precipitation technique) magnetic fluids in varying magnetic field. Experimental investigations were carried out to analyze the heat transfer property of synthesized magnetic fluids (MNF) in varying magnetic field applied in perpendicular direction to the thermal gradient of magnetic fluids. The experimental results indicate that the magnetic fluids show enhancement in heat transfer rate than carrier fluids in absence of magnetic field and it shows decrement in heat transfer rate in presence of varying magnetic field. Thus, the results reveal that the heat transfer characteristics of cobalt manganese ferrite based magnetic fluids was tunable by controlling the direction and influence of magnetic field strength. This tunable heat transfer property of cobalt manganese ferrite based magnetic fluids could be applicable in heat transport phenomena of transformers and in microelectronic devices. [ABSTRACT FROM AUTHOR]

As many potential alternative jet fuels would be used in the in-service engine, such as the most promising Fischer–Tropsch (F–T) jet fuel, it's necessary to test their performance in compared with petroleum derived jet fuel. In this study, atomization performance of F–T fuel and traditional RP-3 jet fuel were assessed based on three parameters including Sauter mean diameter, Spray cone angle, and Distribution index N. Thermogravimetric (TG) analysis is also conducted for kinetics analysis. TG experiments of F–T fuel and RP-3 were carried out in order to establish the relationship between atomization and TG characteristics. Burnout index B f and uniform parameter α derived based on TG experiments were defined in this study. The qualitative relationship between B f , α and atomization parameters were given for rapid evaluation of alternative jet fuel's atomization characteristics. [ABSTRACT FROM AUTHOR]

In spite of the fact that in most applications, magnesium alloys are intended for operation in environments with room temperature, these alloys are subject to elevated temperature and oxidizing atmosphere in various stages of preparation (casting, welding, thermal treatment). At present, the studies focus on development of alloys with magnesium matrix, intended for plastic forming. The paper presents results of studies on oxidation rate of WE43 and ZRE1 magnesium foundry alloys in dry and humidified atmosphere of N2+1%O2. Measurements of the oxidation rate were carried out using a Setaram thermobalance in the temperature range of 350-480°C. Corrosion products were analyzed by SEM-SEI, BSE and EDS. It was found that the oxide layer on the WE43 alloy has a very good resistance to oxidation. The high protective properties of the layer should be attributed to the presence of yttrium in this alloy. On the other hand, a porous, two-layer scale with a low adhesion to the substrate forms on the ZRE1 alloy. The increase in the sample mass in dry gas is lower than that in humidified gas. [ABSTRACT FROM AUTHOR]

The newly developed HITECOM reactor provides the possibility of in-situ analysis of single particle reactions. It combines the capabilities of a magnetic suspension thermobalance with state of the art optical analysis. The surface temperature and carbon conversion of single particles are measured under well-defined flow conditions. The generated data enables the detailed validation of CFD single particle models. For this reactor, a special temperature resistant particle holder had to be constructed, which is able to fix various particles in direct flow during gasification. An in-situ Raman spectroscopy setup was established for quantitative gas analysis at pressures between 1 and 20 bar and temperatures up to 965 °C. Here, a pulsed Nd:YAG laser at 355 nm was used as excitation source. The Rayleigh/Raman scattering was measured perpendicular to the flow direction with a spectrograph and ICCD camera. From the recorded spectra the gas concentrations were calculated. Generally, the calculated concentrations of CO, CO 2 and N 2 match the reference values from the gas chromatograph. In the present study, single coal particles of one Central German lignite and one hard coal were analyzed and monitored during gasification. The particle diameter ranged from 1 to 3 mm. Gasification experiments with CO 2 were carried out under isothermal conditions at 1 bar total pressure and temperatures of 800–1200 °C. The experimental data were adjusted with models by data fitting. It was found that the Random Pore Model (RPM) matches the carbon conversion of the hard coal sample and the Shrinking Core Model (SCM) matches the carbon conversion of the lignite sample. Further analysis revealed that inhomogeneous particles affect gasification kinetics. The differences in reactivity between several particles from the hard coal are significantly larger than for the lignite particles, which is in accordance to the results of the respective ultimate and proximate analyses. Additionally, it was discovered that the difference between gas and particle temperature is negligible for low reactive feedstocks within the investigated temperature range (ΔT ⩽ 5 K at 1070 °C, hard coal), whereas there was a significant difference for reactive particles (ΔT ⩽ 40 K at 1070 °C, lignite). [ABSTRACT FROM AUTHOR]

Marine debris (MDs) produces a wide variety of negative environmental, economic, safety, health and cultural impacts. Most marine litter has a very low decomposition rate (plastics), leading to a gradual accumulation in the coastal and marine environment. Characterization of the MDs has been done in terms of their pollutant content: PAHs, ClBzs, ClPhs, BrPhs, PCDD/Fs and PCBs. The results show that MDs is not a very contaminated waste. Also, thermal decomposition of MDs materials has been studied in a thermobalance at different atmospheres and heating rates. Below 400–500 K, the atmosphere does not affect the thermal degradation of the mentioned waste. However, at temperatures between 500 and 800 K the presence of oxygen accelerates the decomposition. Also, a kinetic model is proposed for the combustion of the MDs, and the decomposition is compared with that of their main constituents, i.e., polyethylene (PE), polystyrene (PS), polypropylene (PP), nylon and polyethylene-terephthalate (PET). [ABSTRACT FROM AUTHOR]

A plate reactor was designed to investigate the catalytic soot oxidation applying glass ceramic plates coated with lithium zirconate. The results are compared to the corresponding powder catalysts in thermogravimetric experiments. The deposition of soot by spray coating resulted in an intimate contact mode equivalent to the mortaring preparation of the tight contact powder samples. In the presence of lithium ions the soot oxidation temperature was decreased significantly both in the thermobalance and in the plate reactor. [ABSTRACT FROM AUTHOR]

The pyrolysis process of a lower rank coal as a fresh coal (FC) and a long-term stored coal (LTSC) was analyzed in a laboratory coking unit using X-raying and thermobalance. The changes in temperature of the charge of coals were determined along with the changes in volume of their carbonized charges, the mass loss of coals, and the mass loss rate. It was stated that LTSC has a lower thermal diffusivity at the stage of coal grain swelling and shows an almost twofold growth in charge volume at this stage. The samples of carbonized coals that correspond to the plasticity stage were investigated using the FT-IR and SEM methods. The pyrolysis products of coals were analyzed by the TG/FT-IR method. It is suggested that the formation of nano-size films and spherical objects in the pores of the plastic mass of LTSC results from an increase in content of non-saturated hydrocarbons, aldehydes, phenols, and alcohols in volatile products of pyrolysis of this coal. [ABSTRACT FROM AUTHOR]

The influence of chlorinated paraffin/titanium (C 24 H 29 Cl 21 /Ti) additives on burning and radiance performances of Magnesium/Teflon/Viton™ (MTV) foil-type was investigated via a high-speed camera, high-temperature differential thermobalance, far-infrared thermal imager and Fourier Transform Infrared (FTIR) remote-sensing spectrometer. We found that the burning temperature, radiance brightness, radiance area and radiance intensity after addition of C 24 H 29 Cl 21 /Ti are improved by 124–196 °C (8–13%), 300–475 W·m −2 ·sr −1 (12–19%), 943–1422 mm 2 (67–101%) and 3.17–4.99 W·sr −1 (88–138%), respectively, and are maximized at the addition ratio of 10%. The substances formed by adding C 24 H 29 Cl 21 /Ti could improve the middle and far infrared radiation. [ABSTRACT FROM AUTHOR]

Introduction: We investigated if "thermobalancing" therapy (TT), using Dr Allen's therapeutic device (DATD) in men with benign prostatic hyperplasia (BPH), can aid in understanding the etiology and pathophysiology of BPH.Methods: We compared urinary and other parameters of BPH patients who received TT over 6 months (treatment group) with those of healthy volunteers who had not received the treatment (control group). Dynamics of symptoms and indicators in each group were evaluated in comparison with their data at the beginning and end of the study. Parameters were the International Prostate Symptom Score (IPSS) for urinary symptoms and quality of life (QoL), ultrasound measurement of prostate volume (PV) and uroflowmetry (maximum flow rate, Qmax). TT effectiveness was examined in 124 men with BPH and PV <60 mL. We also investigated the data of five patients with BPH and PV >60 mL.Results: TT decreased urinary symptoms and PV, increased Qmax and improved QoL in men with BPH, PV <60 mL, and in men with BPH, PV >60 mL.Conclusions: The present study demonstrated that TT is effective for BPH, suggesting that blood circulation plays a crucial role in its cause. The continuous heat exposure that does not exceed the normal body temperature terminates the trigger of BPH development, "micro-focus" of hypothermia, and the following spontaneous expansion of capillaries. TT could be considered to be a useful tool in BPH treatment. [ABSTRACT FROM AUTHOR]

The catalytic effects of brine sludge (rich in NaCl), iron mud (rich in Fe 2 CO 3 ), steel slag (rich in Fe 2 SiO 4 and α-Fe) and calcium carbide residue (rich in Ca(OH) 2 ) on coal combustion were compared with those of pure NaCl and ZnCl 2 . Thermobalance experiments showed that the catalytic effects of NaCl and brine sludge on coal combustion were better than those of the others. NaCl and brine sludge reduced the ignition temperature of Jincheng anthracite coal from 582 °C to 560 °C and 561 °C. This result was achieved because Na 2 O 2 more easily obtained electrons from carbon as a result of the lower ionisation energy of the alkali metal Na. This attribute promoted the transport of the oxygen atom from the metal oxide to carbon. A novel cascade chain catalytic mechanism of Na–Fe–Ca composite promoters on coal combustion was proposed. In this mechanism, the oxygen atom was transported based on the order of metal catalytic activity from Na to Fe to Ca to carbon. Conversely, the electrons were transported in the reversed order. The Na–Fe–Ca composite promoters of industrial wastes exhibited better catalytic effects on coal combustion than the individual components, reducing the ignition temperature of Jincheng anthracite coal from 582 °C to 550 °C and augmenting burnout efficiency from 91.8% to 95.4%. [ABSTRACT FROM AUTHOR]

β-Thalassemia is a hemoglobin genetic disorder characterized by the absence or reduced β-globin chain synthesis, one of the constituents of the adult hemoglobin tetramer. In this study the possibility of using thermogravimetric analysis (TGA) followed by chemometrics as a new approach for β-thalassemia detection is proposed. Blood samples from patients with β-thalassemia were analyzed by the TG7 thermobalance and the resulting curves were compared to those typical of healthy individuals. Principal Component Analysis (PCA) was used to evaluate the correlation between the hematological parameters and the thermogravimetric results. The thermogravimetric profiles of blood samples from β-thalassemia patients were clearly distinct from those of healthy individuals as result of the different quantities of water content and corpuscular fraction. The hematological overview showed significant decreases in the values of red blood cell indices and an increase in red cell distribution width value in thalassemia subjects when compared with those of healthy subjects. The implementation of a predictive model based on Partial Least Square Discriminant Analysis (PLS-DA) for β-thalassemia diagnosis, was performed and validated. This model permitted the discrimination of anemic patients and healthy individuals and was able to detect thalassemia in clinically heterogeneous patients as in the presence of δβ-thalassemia and β-thalassemia combined with Hb Lepore. TGA and Chemometrics are capable of predicting ß-thalassemia syndromes using only a few microliters of blood without any pretreatment and with an hour of analysis time. A fast, rapid and cost-effective diagnostic tool for the β-thalassemia screening is proposed. [ABSTRACT FROM AUTHOR]

The study concerns the pyrolysis kinetics of exhausted pine cone shell after its use as biosorbent of copper and lead from aqueous solutions in a fixed bed column. First, breakthrough curves of biosorption process were obtained. Main dynamic biosorption parameters were determined and analyzed. Then, non-isothermal thermogravimetric experiments were carried out with raw and metal-loaded biomass in a thermobalance under nitrogen atmosphere at different heating rates. A comparative study was performed. The activation energy dependent on the conversion rate was estimated by Flynn–Wall–Ozawa (a free integral or iso-conventional method) and a mechanistic model (an integral or model-fitting method that considers three independent parallel reactions). The fluctuation of activation energy in Flynn-Wall Ozawa model can be considered the result of thermal degradation reactions of different pseudo-components of the lignocellulosic material (hemicellulose, cellulose and lignin). For raw pine cone shell and metal-loaded-pine cone shell, best fit parameters were determined according to a three independent parallel reactions scheme. The copper and lead present in metal-loaded samples did not modify values of determined parameters which describe the pyrolysis process. Finally, chemical analysis of the chars indicated that about 95% and 99% of copper and lead presented on original waste was recovered in generated chars. [ABSTRACT FROM AUTHOR]

A study was performed to elucidate the influence of biomass type on char steam gasification kinetics. Isothermal experiments were carried out in a thermobalance in chemical regime on nineteen biomass chars produced under the same conditions. The reactivity obtained varied of a factor of more than thirty. This large difference appeared to be correlated with the biomass inorganic elements. In particular, the catalytic effect of potassium (K) as well as the inhibiting effect of silicon (Si) and phosphorus (P) were highlighted. Three different types of rate evolution versus conversion could be observed depending on the ratio K/(Si + P) and were correlated with the ash surface composition after gasification. Conversion could be satisfactorily predicted versus time through simple models taking into account the influence of inorganic elements and thus further useable in simulation of industrial gasifiers fed by various biomass types. [ABSTRACT FROM AUTHOR]

The AlSBA-15 nanomaterials with different Si/Al ratios were investigated as a promising material for processing of atmospheric residue of petroleum (ATR). The processing was performed in a thermobalance using nitrogen as a carrier gas at different heating hates. The catalytic pyrolysis was performed with ATR sample containing 20% mass of AlSBA-15. Based on TG data by applying Ozawa-Flynn-Wall kinetic model, the activation energy for the pyrolysis of ATR was higher than for the ATR/AlSBA-15, throughout all range of decomposition, indicating that the nanostructured material is a promising material for processing petroleum residues in order to obtain liquid products in the gasoline and diesel range. [ABSTRACT FROM AUTHOR]

Many instruments used for measuring of moisture content in solid materials, such as thermobalances and Karl Fisher titrators, require calibration or verification. The calibration could be performed by using some hydrated ionic compounds [such as lactose monohydrate, sodium tartrate dihydrate (STDH), potassium citrate monohydrate (PCMH), among others], which require the certification in their moisture content value. The moisture content of these compounds could be obtained theoretically, however there are few published papers about the measured values and their uncertainty. The measurement of moisture content of these materials could be performed by the oven drying method. In this work, the measurement process of the moisture content of STDH and PCMH using a forced convection drying oven is described. The obtained results are showing that is possible to reach uncertainties smaller than 0.06 % ( k = 1) of moisture content for these compounds, whose values are good enough for the calibration and verification of thermobalances and Karl Fisher equipments. [ABSTRACT FROM AUTHOR]

In this study, the hyphenation of a thermobalance to an ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometer (UHR FTICR MS) is presented. Atmospheric pressure chemical ionization (APCI) is used for efficient ionization. The evolved gas analysis (EGA), using highresolution mass spectrometry allows the time-resolved molecular characterization of diermally induced processes in complex materials or mixtures, such as biomass or crude oil. The most crucial part of the setup is the hyphenation between the thermobalance and the APCI source. Evolved gases are forced to enter the atmospheric pressure ionization interface of the MS by applying a slight overpressure at the thermobalance side of the hyphenation. Using the FTICR exact mass data, detailed chemical information is gained by calculation of elemental compositions from the organic species, enabling a time and temperature resolved, highly selective detection of the evolved species. An additional selectivity is gained by the APCI ionization, which is particularly sensitive toward polar compounds. This selectivity on the one hand misses bulk components of petroleum samples such as alkanes and does not deliver a comprehensive view but on the other hand focuses particularly on typical evolved components from biomass samples. As proof of principle, the thermal behavior of different fossil fuels: heavy fuel oil, light fuel oil, and a crude oil, and different lignocellulosic biomass, namely, beech, birch, spruce, ash, oak, and pine as well as commercial available softwood and birch-bark pellets were investigated. The results clearly show the capability to distinguish between certain wood types through their molecular patterns and compound classes. Additionally, typical literature known pyrolysis biomass marker were confirmed by their elemental composition, such as coniferyl aldehyde (C10H10O3), sinapyl aldehyde (C11H12O4), retene (C18H18), and abietic acid (C20H30O2). [ABSTRACT FROM AUTHOR]

In this paper, a new equation set describing transient heat transfer process in tube and fin cross-flow heat tube exchanger will be given and subsequently solved using the finite volume method. A numerical model of a single-row heat exchanger and double-row car radiator with two passes has been developed. Based on thermal and hydraulic measurements of a double row car radiator the experimental correlations were determined to calculate the Nusselt number on the air- and water-side. The results of numerical modeling reflect very well transient operation of the actual heat exchanger. A good agreement between numerical and experimental results was obtained. Using the method presented in the paper, one can build a mathematical model of a cross-flow plate-fin and tube heat exchanger with complicated tube arrangement. [ABSTRACT FROM AUTHOR]

Methane appears to be a fuel of great interest for solid oxide fuel cell (SOFC) systems because it can be directly converted into hydrogen by Internal Reforming within the SOFC anode. To cope with carbon formation, a new SOFC cell configuration combining a catalyst layer with a classical anode was developed. The rate of the CH4 consumption in the catalyst layer (Ir-CGO) was determined experimentally for small values of steam to carbon ratios. This paper proposes a modelling and a simulation, using the CFD-Ace software package, of the behaviour of a SOFC operated in Gradual Internal Reforming (GIR) conditions. This model of SOFC takes into account the kinetics of the steam reforming reaction in the catalyst layer in order to assess the influence of the steam to carbon ratio and the cell polarization. Because the risk of carbon formation is greater under GIR operation, a detailed thermodynamic analysis was carried out. Thermodynamic equilibrium calculations allowed us to predict the conditions of carbon formation occurrence. [ABSTRACT FROM AUTHOR]

This paper deals with the two dimensional modelling of transient pyrolysis of biomass in a fixed bed. The model that is developed mainly relies on the theory of volume averaging. This model includes heat and mass transfer and pyrolysis reaction. It allows the prediction of temperature, moisture content organic material content, and char content, as well as the prediction of internal evolution of the composition of the gas held and released from the sample under investigation. This model is used in order to describe pine wood pyrolysis taking place in a macro thermobalance which is also presented in the paper. Comparison of the numerical results with the experimental ones, in terms of mass loss of the sample, shows good agreement and validates the model. A deeper analysis of the results allows a better understanding of the processes involved in the thermal degradation. [ABSTRACT FROM AUTHOR]

In this paper, we consider a one-dimensional linear thermoelastic system of Timoshenko type with a delay term in the feedback. The heat conduction is given by Cattaneo's law. Under an appropriate assumption between the weight of the delay and the weight of the damping, we prove the well-posedness of the problem. Furthermore, an exponential stability result is shown without the usual assumption on the wave speeds. To achieve our goals, we make use of the semigroup method and the energy method. [ABSTRACT FROM AUTHOR]

The present paper presents an isothermal analysis of the oxidation behavior in which hot-pressed compacts rather than powders are used over the temperature range 700-850 °C. This was done to better simulate the extent of oxidation occurring on use. WC-Co powders were first subjected to non-isothermal kinetic analysis to follow the oxidation mechanism. In the isothermal runs, a thermobalance was used to follow up the mass with time at different constant temperatures. The diameter of compacts was measured as function of time at these temperatures, and a simple model was proposed to relate the diameters to extent of oxidation. Two reactions were found to take place that are controlled by chemical reaction at interface: Oxidation of cobalt and oxidation of WC with the formation of WO and CoWO. The activation energies for the two steps of oxidation were calculated and found to equal 157 kJ mol and 205 kJ mol, respectively. These values are in reasonable agreement with published data for WC-Co powders. [ABSTRACT FROM AUTHOR]

A removal of different metals using both acid reflux and the microwave assisted digestion method was investigated. As a carbon material multi-walled carbon nanotubes synthetized on iron, cobalt and iron–cobalt catalysts without support were applied. The amount of metal particles after purification was determined using a thermobalance and it was found that microwave heating improved the efficiency of purification, especially at elevated pressure. Similar removal degrees of catalyst particles were achieved using the acid reflux method for 24 h and microwave heating for 15 min at 20 at regardless of the kind of metal. Raman measurements indicate that all the obtained samples were characterized with a high ratio of peak IG/ID intensities which confirms a good quality of the materials. [ABSTRACT FROM AUTHOR]

Coking dynamics of Ni-based and Ni-free catalysts were studied in a magnetic suspension thermobalance under methane dry reforming conditions. Ni-rich catalysts undergo strong coking featured with a surface saturation point where the coking rate is drastically reduced. Catalyst resistance towards coking may be enhanced by using noble-metal-based Ni-free precursors or decreasing the Ni content in the catalytic system. The post reaction performed temperature-programmed oxidation experiment of the coked catalyst is diffusion-limited due to large amounts of formed carbon. [ABSTRACT FROM AUTHOR]

Torrefaction tests were carried out in a thermobalance and in a lab-scale device on beechwood and on its constituents - cellulose, lignin and xylan. The main volatile species measured were water, formaldehyde, acetic acid and carbon dioxide. Thanks to measurement before volatiles condensation, the yield of formaldehyde was shown to be higher than usually observed in literature. Smaller amounts of methanol, carbon monoxide, formic acid and furfural were also quantified. Each constituent did not produce all species. Beech torrefaction could be described by the summative contribution of its three constituents up to 250 °C. At 280 °C and 300 °C, tests performed with constituents mixtures showed that there were interactions between cellulose and the two other constituents. A hypothetical mechanism was proposed to explain these interactions. [ABSTRACT FROM AUTHOR]

The direct production of methane through steam–coal gasification processing using a catalyst is one of the most attractive routes for the effective utilization of coal. In this study, a thermobalance was used to verify basic characteristics of carbon and steam reactivity using the ultra clean coal (UCC) char of Roto South with potassium carbonate at different conditions. The reactivity between carbon and steam was the highest at 800 °C, with catalyst (K 2 CO 3 ) addition, 10 wt%, and the steam flow rate of 500 ml/min. At the optimized condition of thermobalance, syngas components of Roto South coal, which were produced in fixed-bed reactor, were observed through a Non-dispersive infrared sensor (NDIR) for 60 min. Methane concentration among the produced gases highly accounted for 36 vol% at 6 min. The volatile matter (VM) of coal was related to high methane production. From the X-ray diffraction (XRD) results, the crystallinity structure of K 2 CO 3 was detected, as other potassium salts form, after 20 min. [ABSTRACT FROM AUTHOR]

Abstract: Boron is an attractive fuel for propellants and explosives because of its high energy density. However, boron particles are difficult to combust because of inhibiting oxide layers that cover the particles. The use of magnesium as additives has been shown to promote boron oxidation. In this study, laser ignition facility and thermobalance were used to investigate the effect of magnesium on the burning characteristics of boron particles. The influences of magnesium addition on sample combustion flame, boron ignition delay time, boron combustion efficiency and initial temperature of boron oxidation. Results show that all Mg/B samples exhibit the same type of flame structure, i.e., a bright plume surrounded by green radiation which is interpreted as BO2 emission. The combustion flame intensity of a sample increases with the increasing magnesium content of boron particles. An increase in magnesium content results in a decrease and a subsequent increase in boron ignition delay time. (Mg/B)0.2 has a minimum ignition delay time of ~48ms. Boron combustion efficiency increases with increasing magnesium addition. (Mg/B)0.5 shows a maximum boron combustion efficiency of ~64.2%. Magnesium addition decreases the initial temperature of boron oxidation. [Copyright &y& Elsevier]

Abstract: Volatile–char interaction is important for the operation of co-gasification of coal and biomass. Biomass generally produces large amount of volatiles while char is mainly produced from coal. Hence, in this study, the interaction between coal char and volatiles from biomass samples (xylan, cellulose and rice straw) was examined using a rapid-heating thermobalance reactor. Three types of coal char, consisting of slow pyrolyzed-coal char (Ex-char), fast pyrolyzed-coal char (In-char), and acid washed-coal char (Ac-char), were employed to reveal influences of heating rate during char preparation and retention of alkali and alkaline earth metallic (AAEM) species on char surface. The steam gasification rates of all coal chars in both cases with and without volatile contacting were investigated from the gas evolution rate and remaining char analyses. The results indicate that the steam gasification rates of Ex-char and In-char were significantly diminished by the volatiles derived from all sources, especially rice straw. However, in the case of Ac-char, the reduction of steam gasification rate was less important. Moreover, the Ex-char exhibited the catalyst for the decomposition of biomass volatiles, resulting in the increase in gas production rate. Porous structure and the AAEM over char play crucial roles on the volatile–char interaction. [Copyright &y& Elsevier]

The pyrolysis behaviour and kinetics of forest shrub wastes (Cytisus multiflorus, Spartium junceum, Acacia dealbata and Pterospartum tridentatum) from the Portuguese Central Inland Region have been studied in a thermobalance, as a previous step for their valorization by pyrolysis in order to obtain fuels and chemicals within the framework of the BioREFINA-Ter project. The kinetic model consists of a multi-component mechanism that describes the volatile formation involving three independent and parallel reaction networks corresponding to the decomposition of the three main biomass pseudo-components: hemicellulose, cellulose and lignin. The thermogravimetric curves and kinetic parameters have been compared with those obtained for other materials, and the chemical features of the biomasses have been determined. Although the samples are highly heterogeneous because of their bark and leaf content, the degradation of these shrubby biomasses is similar to other lignocellulosic materials, evidencing that their valorization by pyrolysis is feasible. [ABSTRACT FROM AUTHOR]

Kotaro Honda (2/23/1870-2/12/1954) graduated from the Department of Physics, Tokyo Imperial University in 1897. Between 1907 and 1911, he stayed in Europe, and spent the majority of his time at Göttingen University to study physical metallurgy under Professor Gustav Tammann. In 1911, he returned to Japan and was nominated professor of physics at Tohoku Imperial University, Sendai. An university-affiliated institute for research on iron and steel was established on a permanent basis in 1919, and the institute developed to the Research Institute for Iron, Steel, and Other Metals (RIISOM, KINKEN in Japanese) in 1922. Professor Honda served as the Director of the Institute until 1933. The RIISOM was reorganized as a national collaborative research institute named Institute for Materials Research in 2001. Professor Honda and his colleagues achieved distinguished research works of physical metallurgy, in which thermoanalytical techniques such as differential thermal analysis (DTA), thermodilatometry and thermomagnetometry were utilized effectively. Professor Honda also played an important role in the field of thermogravimetry (TG) by means of the first development of the thermobalance. In the present paper, Honda's original thermobalance, various modifications carried out by his school, the commercialized Honda's thermobalance and other related matters are briefly summarized. [ABSTRACT FROM AUTHOR]

Abstract: Using CALPHAD methods, Cr2O3 growth on pure Cr is modeled using DICTRA and the vacancy model for diffusion. The results are compared with thermobalance and TEM experiments at 625 and 700°C in O2. The experimental scatter is significant, leading to a compromise suggestion. With the experimental conditions from the furnace exposures in this work, optimized mobilities are validated with a series of oxidation simulations. Despite the complex microstructure and initial growth rate variations, it is possible to reproduce the experimental oxide thicknesses with good accuracy, allowing for extension to multicomponent systems. [Copyright &y& Elsevier]