Jet milling effect on wheat flour characteristics and starch hydrolysis.

The interest for producing wheat flour with health promoting effect and improved functionality has led to investigate new milling techniques that can provide finer flours. In this study, jet milling treatment was used to understand the effect of ultrafine size reduction onto microstructure and physicochemical properties of wheat flour. Three different conditions of jet milling, regarding air pressure (4 or 8 bars) feed rate and recirculation, were applied to obtain wheat flours with different particle size (control, F1, F2 and F3 with d50 127.45, 62.30, 22.94 and 11.4 µm, respectively). Large aggregates were gradually reduced in size, depending on the intensity of the process, and starch granules were separated from the protein matrix. Damaged starch increased while moisture content decreased because of milling intensity. Notable changes were observed in starch hydrolysis kinetics, which shifted to higher values with milling. Viscosity of all micronized samples was reduced and gelatinization temperatures (To, Tp, Tc) for F2 and F3 flours increased. Controlling jet milling conditions allow obtaining flours with different functionality, with greater changes at higher treatment severity that induces large particle reduction.

Non-Contact and Self-Calibrated Photopyroelectric Method for Complete Thermal Characterization of Porous Materials.

A general theory of a photopyroelectric (PPE) configuration, based on an opaque sample and transparent pyroelectric sensor, backing and coupling fluids is developed. A combined back-front detection investigation, based on a frequency scan of the phase of the PPE signals, followed by a self-normalization of the phases' behavior, leads to the possibility of simultaneously measuring both thermal effusivity and diffusivity of a solid sample. A particular case of this configuration, with no coupling fluid at the sample/backing interface and air instead of coupling fluid at the sample/sensor interface (non-contact method) is suitable for simultaneous measurement ofboth thermal diffusivity and effusivity (in fact complete thermal characterization) of porous solids. Compared with the already proposed configurations for investigations of porous materials, this novel configuration makes use of a fitting procedure with only one fitting parameter, in order to guarantee the uniqueness of the solution. The porous solids belong to a class of materials which are by far not easy to be investigated using PPE. To the best of our knowledge, porous materials represent the only type of compounds, belonging to condensed matter, which were not taken into consideration (until recently) as potential samples for PPE calorimetric investigations. Consequently, the method proposed in this paper complete the area of applications of the PPE method. Applications on some porous building materials and cellulose-based samples validate the theory.

Experimental and Theoretical Investigations of Three-Ring Ester/Azomethine Materials.

New three-ring ester/azomethine homologues series, (E)-4-((4-hydroxybenzylidene)amino)phenyl 4-(alkoxy)benzoate In, were prepared and their properties were investigated experimentally and theoretically. FT-IR, NMR, and elemental analyses were used to confirm the chemical structures of the synthesized compounds. The mesomorphic activities of the planned homologues were evaluated using differential scanning calorimetry (DSC) and polarized optical microscopy. All of the homologous examined were found to have non-mesomorphic properties. Theoretical calculations using the density functional theory (DFT) were used to validate the experimental data and determine the most stable conformation of the synthesized compounds. All calculated conformers' thermal properties, dipole moments, and polarizability were discussed. The results show that the terminal alkoxy chain length affects the thermal parameters of the conformers. The correlations between these parameters' values and the conformer type were demonstrated. The base component was expected to be in two conformers according to the orientation of the N atom of imine-linkage. DFT calculations revealed the more probable of the two possible conformers, and the incorporation of the alkoxy terminal chain in one position affect its geometrical and mesomerphic characteristics.

FFF 3D Printing in Electronic Applications: Dielectric and Thermal Properties of Selected Polymers.

The present study is a focused and comprehensive analysis of the dielectric and thermal properties of twenty-four 3D printed polymers suitable for fused filament fabrication (FFF) in electronic applications. The selected polymers include various thermoplastic elastomers, such as thermoplastics based on polycarbonate (PC), polyethylene terephthalate glycol (PETG), and acrylonitrile butadiene styrene (ABS-T). Their overall thermal behavior, including oxidation stability, glass transition, and melting temperature, was explored using simultaneous thermal analysis (STA) and differential scanning calorimetry (DSC). Considering their intended usage in electronic applications, the dielectric strength (Ep) and surface/volume resistivity (ρs/ρv) were comprehensively tested according to IEC 60243-1 and IEC 62631-3, respectively. The values of the dielectric constant (ε') and loss factor (ε") were also determined by broadband dielectric spectroscopy (BDS). While, on the one hand, exceptional dielectric properties were observed for some thermoplastic elastomers, the materials based on PCs, on the other hand, stood out from the others due to their high oxidation stability and above average dielectric properties. The low-cost materials based on PETG or ABS-T did not achieve thermal properties similar to those of the other tested polymers; nevertheless, considering the very reasonable price of these polymers, the obtained dielectric properties are promising for undemanding electronic applications.

Synthetic, Mesomorphic, and DFT Investigations of New Nematogenic Polar Naphthyl Benzoate Ester Derivatives.

Four new non-symmetrical derivatives based on central naphthalene moiety, 4-((4-(alkoxy)phenyl) diazenyl)naphthalen-1-yl 4-substitutedbenzoate (In/x), were prepared, and their properties were investigated experimentally and theoretically. The synthesized materials bear two wing groups: an alkoxy chain of differing proportionate length (n = 6 and 16 carbons) and one terminal attached to a polar group, X. Their molecular structures were elucidated via elemental analyses and FT-IR and NMR spectroscopy. Differential scanning calorimetry (DSC) and polarized optical microscopy (POM) were carried out to evaluate their mesomorphic properties. The results of the experimental investigations revealed that all the synthesized analogues possess only an enantiotropic nematic (N) mesophase with a high thermal stability and broad range. Density functional theory (DFT) calculations were in accordance with the experimental investigations and revealed that all prepared materials are to be linear and planar. Moreover, the rigidity of the molecule increased when an extra fused ring was inserted into the center of the structural shape, so its thermal and geometrical parameters were affected. Energy gap predictions confirmed that the I16/c derivative is more reactive than other compounds.

Indoor air pollution, physical and comfort parameters related to schoolchildren's health: Data from the European SINPHONIE study.

Substantial knowledge is available on the association of the indoor school environment and its effect among schoolchildren. In the same context, the SINPHONIE (School indoor pollution and health: Observatory network in Europe) conducted a study to collect data and determine the distribution of several indoor air pollutants (IAPs), physical and thermal parameters and their association with eye, skin, upper-, lower respiratory and systemic disorder symptoms during the previous three months. Finally, data from 115 schools in 54 European cities from 23 countries were collected and included 5175 schoolchildren using a harmonized and standardized protocol. The association between exposures and the health outcomes were examined using logistic regression models on the environmental stressors assessed in classroom while adjusting for several confounding factors; a VOC (volatile organic compound) score defined as the sum of the number of pollutants to which the children were highly exposed (concentration > median of the distribution) in classroom was also introduced to evaluate the multiexposure - outcome association. Schoolchildren while adjusting for several confounding factors. Schoolchildren exposed to above or equal median concentration of PM2.5, benzene, limonene, ozone and radon were at significantly higher odds of suffering from upper, lower airways, eye and systemic disorders. Increased odds were also observed for any symptom (sick school syndrome) among schoolchildren exposed to concentrations of limonene and ozone above median values. Furthermore, the risks for upper and lower airways and systemic disorders significantly increased with the VOCs score. Results also showed that increased ventilation rate was significantly associated with decreased odds of suffering from eye and skin disorders whereas similar association was observed between temperature and upper airways symptoms. The present study provides evidence that exposure to IAPs in schools is associated with various health problems in children. Further investigations are needed to confirm our findings.

Magnesium Oxychloride Cement Composites with Silica Filler and Coal Fly Ash Admixture.

Worldwide, Portland cement-based materials are the most commonly used construction materials. As the Portland cement industry negatively affects the environment due to the excessive emission of carbon dioxide and depletion of natural resources, new alternative materials are being searched. Therefore, the goal of the paper was to design and develop eco-friendly, low-cost, and sustainable magnesium oxychloride cement (MOC)-based building material with a low carbon footprint, which is characterized by reduced porosity, high mechanical resistance, and durability in terms of water damage. To make new material eco-efficient and functional, silica sand which was used in the composition of the control composite mixture was partially replaced with coal fly ash (FA), a byproduct of coal combustion. The chemical and mineralogical composition, morphology, and particle morphology of FA were characterized. For silica sand, FA, and MgO, specific density, loose bulk density, and particle size distribution were measured. Additionally, Blaine specific surface was for FA and MgO powder assessed. The workability of fresh mixtures was characterized by spread diameter. For the hardened MOC composites, basic structural, mechanical, hygric, and thermal properties were measured. Moreover, the phase composition of precipitated MOC phases and their thermal stability were investigated for MOC-FA pastes. The use of FA led to the great decrease in porosity and pore size compared to the control material with silica sand as only filler which was in agreement with the workability of fresh composite mixtures. The compressive strength increased with the replacement of silica sand with FA. On the contrary, the flexural strength slightly decreased with silica sand substitution ratio. It clearly proved the assumption of the filler function of FA, whereas its assumed reactivity with MOC cement components was not proven. The water transport and storage were significantly reduced by the use of FA in composites, which greatly improved their resistance against moisture damage. The heat transport and storage parameters were only slightly affected by FA incorporation in composite mixtures.

Effects of Thermal Variables of Solidification on the Microstructure, Hardness, and Microhardness of Cu-Al-Ni-Fe Alloys.

Aluminum bronze is a complex group of copper-based alloys that may include up to 14% aluminum, but lower amounts of nickel and iron are also added, as they differently affect alloy characteristics such as strength, ductility, and corrosion resistance. The phase transformations of nickel aluminum-bronze alloys have been the subject of many studies due to the formations of intermetallics promoted by slow cooling. In the present investigation, quaternary systems of aluminum bronze alloys, specifically Cu-10wt%Al-5wt%Ni-5wt%Fe (hypoeutectoid bronze) and Cu-14wt%Al-5wt%Ni-5wi%Fe (hypereutectoid bronze), were directionally solidified upward under transient heat flow conditions. The experimental parameters measured included solidification thermal parameters such as the tip growth rate (VL) and cooling rate (TR), optical microscopy, scanning electron microscopy (SEM) analysis, hardness, and microhardness. We observed that the hardness and microhardness values vary according to the thermal parameters and solidification. We also observed that the Cu-14wt%Al-5wt%Ni-5wi%Fe alloy presented higher hardness values and a more refined structure than the Cu-10wt%Al-5wt%Ni-5wt%Fe alloy. SEM analysis proved the presence of specific intermetallics for each alloy.

Directivity patterns of laser-generated sound in solids: Effects of optical and thermal parameters.

In the present paper, directivity patterns of laser-generated sound in solids are investigated theoretically. Two main approaches to the calculation of directivity patterns of laser-generated sound are discussed for the most important case of thermo-optical regime of generation. The first approach, which is widely used in practice, is based on the simple modelling of the equivalent thermo-optical source as a mechanical dipole comprising two horizontal forces applied to the surface in opposite directions. The second approach is based on the rigorous theory that takes into account all acoustical, optical and thermal parameters of a solid material and all geometrical and physical parameters of a laser beam. Directivity patterns of laser-generated bulk longitudinal and shear elastic waves, as well as the amplitudes of generated Rayleigh surface waves, are calculated for different values of physical and geometrical parameters and compared with the directivity patterns calculated in case of dipole-source representation. It is demonstrated that the simple approach using a dipole-source representation of laser-generated sound is rather limited, especially for description of generated longitudinal acoustic waves. A practical criterion is established to define the conditions under which the dipole-source representation gives predictions with acceptable errors. It is shown that, for radiation in the normal direction to the surface, the amplitudes of longitudinal waves are especially sensitive to the values of thermal parameters and of the acoustic reflection coefficient from a free solid surface. A discussion is given on the possibility of using such a high sensitivity to the values of the reflection coefficient for investigation of surface properties of real solids.

Influence of temperature-dependent thermal parameters on temperature elevation of tissue exposed to high-intensity focused ultrasound: numerical simulation.

High-intensity focused ultrasound (HIFU) has been used successfully as a non-invasive modality in treating solid tumors. The temperature rise HIFU irradiation causes in a tissue depends on the thermal properties of the tissue. This study was motivated by our observation that the thermal properties of a tissue vary significantly with temperature (Guntur SR, Lee KI, Paeng DG, Coleman AJ, Choi MJ. Ultrasound Med Biol 2013;39:1771-1784). This research investigated how significantly the alteration of tissue thermal parameters, in the ranges of values measured at 25°C-90°C, affects prediction of the temperature elevation of tissue under the same HIFU exposure. The numerical simulation was performed by coupling a non-linear Khokhlov-Zabolotskaya-Kuznetsov equation with a bio-heat transfer function. In the conventional method of prediction, the thermal parameters were set as constants measured at room temperature (25°C). This study compared the conventional prediction with those predicted with different thermal parameters measured at the various temperatures up to 90°C. The results indicated that the conventional method significantly overestimated the rise in focal temperature in the liver tissue exposed to a clinical HIFU field, compared with the prediction made using thermal parameters measured at temperatures that cause thermal denaturation. This finding suggests that temperature-dependent thermal parameters should be considered in predicting the temperature rise in a tissue to avoid use of an insufficient thermal dose in treatment planning for HIFU surgery.

Troublesome Crystal Structures: Prevention, Detection, and Resolution.

A large number of incorrect crystal structures is being published today. These structures are proving to be a particular problem to those of us who are interested in comparing structural moieties found in the databases in order to develop structure-property relationships. Problems can reside in the input data, e.g., wrong unit cell or low quality intensity data, or in the structural model, e.g., wrong space group or atom types. Many of the common mistakes are, however, relatively easy to detect and thus should be preventable; at the very least, suspicious structures can be flagged, if not by the authors then by the referees and, ultimately, the crystallographic databases. This article describes some of the more common mistakes and their effects on the resulting structures, lists a series of tests that can be used to detect incorrect structures, and makes a strong plea for the publication of higher quality structures.

A method to obtain the thermal parameters and the photothermal transduction efficiency in an optical hyperthermia device based on laser irradiation of gold nanoparticles.

Optical hyperthermia systems based on the laser irradiation of gold nanorods seem to be a promising tool in the development of therapies against cancer. After a proof of concept in which the authors demonstrated the efficiency of this kind of systems, a modeling process based on an equivalent thermal-electric circuit has been carried out to determine the thermal parameters of the system and an energy balance obtained from the time-dependent heating and cooling temperature curves of the irradiated samples in order to obtain the photothermal transduction efficiency. By knowing this parameter, it is possible to increase the effectiveness of the treatments, thanks to the possibility of predicting the response of the device depending on the working configuration. As an example, the thermal behavior of two different kinds of nanoparticles is compared. The results show that, under identical conditions, the use of PEGylated gold nanorods allows for a more efficient heating compared with bare nanorods, and therefore, it results in a more effective therapy.

Relationship of therapeutic effect of uterine fibroids with different intraprocedural thermal parameters during MR-guided high-intensity focused ultrasound ablation / 中国介入影像与治疗学

Objective To explore the relationship of therapeutic effect of uterine fibroids with different intraprocedural thermal parameters during MR-guided high-intensity focused ultrasound (HIFU) ablation.Methods Totally 31 patients with uterine fibroids underwent MR scanning.Thermometry obtained during the treatment was used to create temperature curves.Matlab software was used to analyze the temperature curve to generate several parameters,including heating slope,decay slope,area under heating curve (AUC),heating time,max temperature and time to peak.Spearman correlation test was used to observe the relationship between the shrinkage rate of uterine fibroids 6 months after ablation and the intraprocedural thermal parameters of ablation.Results Six months after ablation,the fibroid volume shrinkage rate was (39.43±27.01) ％.The temperature curve showed the mean heating slope was (0.97±0.84)℃/s,the mean decay slope was (-0.56±0.39)℃/s,the mean AUC was (2 240.03±455.93)℃ · s,the mean heating time was (28.34±12.88)s,the mean max temperature was (47.01±4.63)℃,while the mean time to peak was (22.79±9.47)s.The decay slope showed positive correlation with volume shrinkage rate 6 months after treatment (rs =0.473,P =0.007).ConclusionSlower postsonication temperature decay rate predicts better therapeutic effect of MR-guided HIFU ablation.

Microwave hyperthermia in conjunction with radiotherapy in superficial tumours: correlation of thermal parameters with tumour regression / Hipertermia de microonda de conjunto con radioterapia en los tumores superficiales: correlación de los parámetros térmicos con la regresión del tumor

OBJECTIVE: The aim of the present study is to evaluate the correlation between the thermal parameters of hyperthermia and the clinical outcome in patients with superficial tumours. METHODS: In this study, 20 patients were included with either submandibular lymph nodes from head and neck cancer, or breast cancer relapses post-mastectomy. They were treated with radiation in combination with one session of433 MHz microwave hyperthermia (1 hour, 42.5 ºC-46 ºC). The dose of irradiation ranged from 54 to 60 Gy. The thermal parameters calculated were the minimum volume temperature, the maximum volume temperature and the time interval where the volume temperature was greater than 44 ºC. RESULTS: All patients responded positively to the combined treatment and 60% of the patients showed a complete response. Of the three parameters tested, the only parameter that was found to correlate with the reduction of the tumour diameter was the time with volume temperatures greater than 44 ºC (p < 0.001, Spearman rho). No moderate toxicity was observed. CONCLUSION: Microwave heating should be over 44 ºC for favourable treatment response, when combined with radiotherapy. More patients are needed to confirm the above results.

OJETIVO: El objetivo del presente estudio es evaluar la correlación entre los parámetros térmicos de la hipertermia y el resultado clínico en pacientes con tumores superficiales. MÉTODO: En este estudio, se incluyeron 20 pacientes con ganglios linfáticos submandibulares de cáncer de cabeza y cuello, o post-mastectomía por recidivas de cáncer de mama. Los pacientes fueron tratados con radiación en combinación con una sesión de hipertermia de microondas de 433 MHz (1 hora, 42.5 ºC-46 ºC). La dosis de irradiación osciló entre 54 y 60 Gy. Los parámetros térmicos calculados fueron la temperatura de volumen mínimo, la temperatura de volumen máximo y el intervalo de tiempo donde el volumen de la temperatura fue superior a 44 ºC. RESULTADOS: Todos los pacientes respondieron positivamente al tratamiento combinado y el 60% de los pacientes demostrados una respuesta completa. De los tres parámetros probados, el único parámetro que se comprobó que se correlaciona con la reducción del diámetro del tumor fue el tiempo con temperaturas de volumen superiores a 44 ºC (p < 0.001, rho de Spearman). No se observó ninguna toxicidad moderada. CONCLUSIÓN: Calentamiento por microondas debe estar por encima de 44 ºC para que la respuesta sea favorable al tratamiento en combinación con radioterapia. Se requieren más pacientes para confirmar los resultados anteriores.