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Purpose: The present study aims to test the suitability of a waveguide spectrometer, as a rapid and cheap tool to discriminate different fertilizers according to two different manufacturing methods, such as granulation and blending. Methods: The tested instrument is a waveguide vector spectrometer, patented in 2016, that operates in the range 1.6-2.7 GHz, giving both spectral phase and gain measurements. Granulated and blended fertilizers were dehydrated and pulverized, to avoid possible interferences related to the water content and geometry of the sample. The spectral data were analyzed by multivariate statistical analysis (Principal Component Analysis, PCA and Partial Least Squares-Discriminant Analysis, PLS-DA) in order to obtain a discrimination tool considering the whole hidden spectral information. Results: Principal Component 1 (95% of the explained variance) and Principal Component 2 (4% of the explained variance) shown to explain most part of the spectral variability. A tendency to group samples according to the different production methods can be appreciated even if the discrimination is influenced by the different chemical composition of fertilizers. However, PLS-DA models correctly classified 100% of the samples both by granulated and blended classes using spectra obtained by waveguide spectroscopy. Conclusions: Although preliminary, the tests carried out on a small number of samples show how the technique coupled with PLS-DA models could be able to discriminate the analyzed fertilizers by means of their spectral signature and according to the manufacturing method if the chemical composition is kept constant. Further tests are necessary to validate the model, also considering the possibility of grouping fertilizers for similar composition.

Sorption behavior and glass transition of frozen parsley were investigated in order to study the physical modifications, represented as state diagram to figure out information about product behavior for storage and supply chain handling. Frozen products may be located in the state diagram in all the possible freezing temperatures to understand the structure state and study feasible corrective actions mainly focused on temperature and solid content. Parsley was totally dehydrated and equilibrated at selected relative humidity. Sorption behavior was evaluated by saturated salt slurry method and sorption isotherm fitting, while solid components in terms of mass fraction were investigated by using differential scanning calorimetry. Brunauer–Emmet–Teller (BET) model well fitted with moisture and water activity data (R2 = 0.995, p-level < 0.05). The characteristic ranges of stability, in terms of system mobility and physical modification, are the monolayer values (0.240 water activity; 0.052 kg/kg dry basis) and the critical water activity range (0.424 water activity; 0.078 kg/kg dry basis). Glass transition and melting temperature were used to define parsley state diagram. Different zones figure out a specific physical behavior: depending on solid content and temperature. Unfrozen water was estimated as monolayer BET value 0.84 kg/kg wet basis and extrapolated from state diagram 0.984 kg/kg wet basis. Practical applications: Frozen high-quality product and energy efficiency can be obtained by a correct temperature management. Thermophysical properties of parsley represented in a state diagram are reported in the typical solute and temperature range of freezing process and storage. These data can relate physical structure and temperature, allowing different possible conditions management.

[EN] Wheat flour replacement by rice flour is a key strategy in gluten-free batter production. Rice flour needs hydrocolloids to offset the development of the network of the mix. In this context, the aim of this work was to analyze the influence of chitosan (0-1 g/100 g of batter) addition on the microstructural, rheological and thermal properties of wheat:rice flours batters (100:0; 70:30, 30:70 and 0:100 (g/g)). Results showed that increasing replacement of wheat flour by rice one decreased the consistency (K) and the yield stress (To), and increased the flow behavior index (n) because of the absence or lower gluten content. However, the addition of only 0.25 g/100 g chitosan to rice flour formulation (0:100 (g/g)) increased its viscosity (from 371 to 1006 mPa s), exhibiting a rheological behavior similar to wheat flour formulation (100:0 (g/g) (1050 mPa s)). Chitosan enhanced consistency and structural agglomeration, and the interaction among ingredients, especially in batters with high content of rice flour (30:70 and 0:100 (g/g)). Lastly, chitosan incorporation did not significantly modify thermal properties, excepting in rice-flour batters (0:100 (g/g)), reducing T-m, Delta H-m, and thus, increasing the bound water content (from 17 to 32 g/100 g). (C) 2017 Elsevier Ltd. All rights reserved., The authors want to acknowledge the financial support of Universitat Politecnica de Valencia for the scholarship to support Mariola Sansano Tomas' PhD studies and the mobility grant to University of Bologna (Italy).

The effects of an historical fire were studied on a porous calcarenite coming from an historic building located in Southern Italy. Changes of material properties were investigated on the masonry blocks affected by fire in comparison with the sound stone. They were also compared with thermally induced degradation under controlled heating in laboratory conditions. The stone was affected by a pronounced aesthetical damage consisting of gray and red discoloring. This was the effect of mineralogical-chemical phase transitions, which were detected by diffractometric and thermal analyses. The transformation of goethite to hematite accounted for changes from the original pale yellow color to red. Gray discoloring was found related to burning of organic matter and formation of magnetite. Damage on the stone microstructure was detected by SEM in the form of micro-cracks. It was also investigated through non-destructive ultrasonic propagation velocity tests, which recorded velocity decreases between 6% and 26%. Microfissuring left almost unchanged the bulk density and porosity measured by buoyancy and saturation techniques, as well as the mechanical properties. The latter were assessed by uniaxial compressive tests. A combined experimental protocol, including colorimetry, non-destructive testing and mechanical testing was used to compare the samples conditioned at high temperature in a laboratory environment with those affected by the real fire. The results allowed to estimate that the maximum temperatures within the stone during fire were under 600 °C, up to 300 °C at a depth of about 8 cm. High porosity of the stone accounts for a limited stone damage at microstructural level and consequent low effects on physical-mechanical properties. On the contrary, in the presence of macrocracking due to the thermal shock experienced by the stone in some areas during fire, an UPV decrease of approximately 40% and significant strength reductions between 46 and 55% were found.

This study aims to investigate the physical, chemical, rheological and sensorial properties of six common mango (Mangifera indica) cultivars in Egypt. These common cultivars were Alfonse, Sedeka, Awis, Sinara, Sukari and Zibdia. Weights of mango fruits ranged between 246.6 and 549.2g. The highest significant value of sphericity was in Alfonse fruits (0.82), whereas the lowest value was 0.58 in Sinara fruits. The highest firmness value was 29.51N in Sedeka fruits. The highest elasticity was 1.16N/mm for Sukari fruits. The significantly color intensity chroma was recorded by Sinara, whereas the highest total color index (ΔE) was 88.41 for Sedeka mango cultivar. The significantly lowest pH value was 3.6 for Sinara mango fruits. Awis mango fruits had the significantly highest TSS value (23.67°brix) whereas Sinara fruits had the lowest TSS value (11.33°brix). Rheological properties of Sinara, Zibdia and Sedeka mango pulps are characterized by high values of consistency coeffecient 126.5–156.6dynesn/cm2. Sesonsorially, the significantly sweetest fruits were Sinara, Alfones and Awis whereas the lowest one was Zibdia. There is no bitter taste with all tested mango cultivars either with taste or after taste criteria.

Objective: This study aimed to analyze the following physicochemical properties: radiopacity, final setting time, calcium release, pH change, solubility, water sorption, porosity, surface morphology, and apatite-forming ability of two calcium silicate-based materials. Material and methods: We tested MTA Repair HP and MTA Vitalcem in comparison with conventional MTA, analyzing radiopacity and final setting time. Water absorption, interconnected pores and apparent porosity were measured after 24-h immersion in deionized water at 37°C. Calcium and pH were tested up to 28 d in deionized water. We analyzed data using two-way ANOVA with Student-Newman-Keuls tests (p

Nanocomposites based on maleated poly(styrene-(ethylene-co-butylene)-styrene) copolymer (SEBSgMA) and organo-modified layered double hydroxide (OLDH) have been formulated with the aim to investigate the effects of interfacial interactions between the grafted maleic anhydride groups of the copolymer and the OLDH nanolayers on the rheological properties of nanocomposites. The spectroscopic analysis indicates the establishment of specific polymer/nanofiller interactions, whose extent has been highlighted through morphological and rheological investigations. Specifically, oscillatory melt rheology and shear relaxation tests have been considered in order to deeply investigate the interfacial bridging interactions. Obtained results highlight that SEBSgMA-based nanocomposites containing a high amount of OLDH show solid-like rheological behavior, quite similar to that of crosslinked polymers, attributable to the formation of a gel-like structure.

A combined approach for perceptible quality profiling of apples based on sensory and instrumental techniques was developed. This work studied the correlation between sensory and instrumental data, and defined proper models for predicting sensory properties through instrumental measurements. Descriptive sensory analysis performed by a trained panel was carried out during two consecutive years, on a total of 27 apple cultivars assessed after two months postharvest storage. The 11 attributes included in the sensory vocabulary discriminated among the different apple cultivars by describing their sensory properties. Simultaneous instrumental profiling including colorimeter, texture analyser (measuring mechanical and acoustic parameters) and basic chemical measurements, provided a description of the cultivars consistent with the sensory profiles. Regression analyses showed effective predictive models for all sensory attributes (Q2 ≥ 0.8), except for green flesh colour and astringency, that were less effective (Q2 = 0.5 for both). Interesting relationships were found between taste perception and flesh appearance, and the combination of chemical and colorimeter data led to the development of an effective prediction model for sweet taste. Thus, the innovative sensory-instrumental tool described here can be proposed for the reliable prediction of apple sensory properties.

The spatial distribution of graphene oxide (GO) nanoplatelets in a bromobutyl rubber (BBR) matrix has been tailored by exploiting the rubber latex mixing process to confine nanoparticles among latex microspheres, thus obtaining a segregated arrangement. The gas transport properties and the dielectric behavior of these nanocomposites displaying a 'segregated' morphology have been compared, for different filler contents, to those of BBR/GO nanocomposites in which the nanoparticles are uniformly dispersed within the rubber matrix. Relevant qualitative and quantitative differences emerge from the comparison of the properties of the two families of GO-based samples. It has been found that the segregated morphology enables a significant enhancement of the barrier properties of pristine rubber already at low levels of nanofiller loading. In addition, an exceptionally low value of the electrical percolation threshold has been detected, which is more than one order of magnitude lower than in the case of uniform filler dispersion. These effects are a direct consequence of the assembly and confinement of nanoparticles among the rubber latex microspheres. (C) 2016 Elsevier Ltd. All rights reserved.

This research investigates an external wall system made with hemp-based composites for a possible application in the civil engineering. In particular, the wall system is realized with panels of two different densities. First of all, physical and mechanical properties of the panels are studied, together with fire reaction and resistance behavior. Then, the external wall system is investigated by means of impact energy of the external surface, thermal and acoustic properties. The composite materials exhibit an outstanding and not common combination of properties. This research shows first preliminary results aimed at implementing sustainable processes in the constructions industry.

蒸留水に酵素を溶解したセルラーゼ溶液,ペクチナーゼ溶液,およびセルラーゼ・ペクチナーゼ混合酵素溶液に含浸することで軟化処理したごぼう試料の力学的特性と咀嚼しやすさを示す咬筋活動について検討した。酵素反応時間30分,0.5%酵素濃度溶液含浸試料の破断力が小さくなった。破断力が小さいセルラーゼ・ペクチナーゼ混合酵素溶液含浸試料はコントロール試料に比べ,嚥下開始までの咀嚼回数は少なく,咀嚼時間は長く,また,最大振幅,筋活動量も小さいことが示された。このことより,混合酵素溶液含浸試料はコントロール試料よりも咀嚼しやすいことが示された。, The present study focused on the physical properties and masticability of burdock samples that had been softened through impregnation in enzyme-dissolved distilled water (i.e. cellulase solution, pectinase solution, and cellulase/pectinase mixed solution, respectively.) The rupture force was small for the sample that had been impregnated in 0.5% concentration enzyme solution (with enzyme reaction time of 30 minutes). Compared with the control samples, this samples impregnated in the cellulase/pectinase mixed solution not only demonstrated smaller rupture force but was also found to require less number of times of mastication before start of swallowing; longer time for mastication; the largest magnitude of fluctuation; and smaller muscle activity. These findings suggest that, com-pared with the control samples, the sample that had been impregnated in the mixed enzyme solution was easier to masticate.

In this paper, we present a transverse flux linear generator. We investigate the possibility to use this generator to extract energy from seawaves. We propose an optimization procedure that allows us to obtain an optimized design of the generator. The optimized design of the converter shows a power generation capability index much higher than other renewable systems.

An application of the improved iterative method for the simultaneous determination of the hydraulic properties of growing media using the one-step experiment is described for highly porous media. Substrate hydraulic properties were characterized by the Brooks and Corey equation for water retention, and by the Kozeny power equation for hydraulic conductivity. The iterative procedure has been tested with a particular class of growing media generally used for container plant cultivation, represented by pure peat, pumice, and a 25: 75 Peat: Pumice mix. The previously optimized One-Step method with Peat: Pumice ratio in the range from 1: 0 to 1: 1, was tested on five replications over the new range from 1: 3 to 0: 1. By analyzing the mean cumulative outflow curves recorded versus time, an estimation of hydraulic functions was derived. Estimated water retention was compared with nine experimental datasets and with estimation by the Van Genuchten model. Normalizing the saturated water content, the two models overlap except for the "wet" range near saturation. Estimated hydraulic conductivity was compared with the estimation derived from the Van Genuchten-Mualem equation involving 3 and/or 4-parameter analysis. Comparisons showed a good similarity between model estimations.

Physical properties of some weathered/altered volcanic rocks and their variation with the degree of alteration are described in detail. A series of tests was performed to identify and quantify the progressive degradation of the properties: 1) petrographycal and chemical studies; 2) effective (?e) and total porosity (?t) measurements and 3D pore reconstruction 3) ultrasonic pulse velocity and spatial attenuation (?s) measurements. Four different volcanic lithologies have been tested: i) trachytic lava with abundant crystals; ii) pyroclastic deposits, with lava clasts and pumice elements; iii) green tuff, made prevalently of pumice clasts; and iv) non-welded ignimbrite deposits. Chemical indices of weathering (CIW) reveal large differences (42.73 < Chemical Index of Alteration [CIA] < 69.24) not only between lithotypes, but also between samples. These differences are reflected by physical properties, in particular ?t (6.0 < ?t from X-ray tomography images < 49.8%), ?e (11.0 < ?e from mercury porosimeter < 65.0%) and shear wave velocity values (0.50 < Vs < 2.90 km/s). Pore network evolution with alteration for each lithology is well documented by fractal dimension (D) and ?s. Mean values of porosity are strictly related to P and S wave velocity (Vp and Vs) and the degree of alteration. Values of CIA are well correlated with the degradation trend exhibited by measured physical properties. The combination of techniques to measure the ?t and ?e provides a good estimate of grain size and pore size distribution and rock structure. Defects and particular characteristics in the rock sample (e.g. micro-fractures, voids, cavities and orientation and sizes of certain minerals and clasts) are revealed by ?s values: the smaller the ?s the more homogeneous and less altered is the sample.

Platelet-rich plasma (PRP) is used clinically in liquid or gel form to promote tissue repair. Because of the poor mechanical properties, conventional PRP is often difficult to handle when used in clinical settings and requires secure implantation in a specific site, otherwise when released growth factors could be washed out during an operation. In this study, we analyzed the end product of a recently developed commercially available system (FIBRINET), which is a dense pliable, platelet-rich fibrin matrix (PRFM). We characterized the mechanical properties of PRFM and tested whether PRFM releases growth factors and whether released factors induce the proliferation of mesenchymal stem cells (MSC). Mechanical properties as well as platelet distribution were evaluated in PRFM. PRFM demonstrated robust mechanical properties, with a tear elastic modulus of 937.3 +/- 314.6 kPa, stress at a break of 1476.0 +/- 526.3 kPa, and an elongation at break of 146.3 +/- 33.8 %. PRFM maintained its mechanical properties throughout the testing process. Microscopic observations showed that the platelets were localized on one side of the matrix. Elevated levels of PDGF-AA, PDGF-AB, EGF, VEGF, bFGF and TGF-beta1 were measured in the day 1-conditioned media (CM) of PRFM and growth factor levels decreased thereafter. BMP2 and BMP7 were not detectable. MSC culture media supplemented with 20% PRFM-CM stimulated MSC cell proliferation; at 24 and 48 hours the induction of the proliferation was significantly greater than the induction obtained with media supplemented with 20% foetal bovine serum. The present study shows that the production of a dense, physically robust PRFM made through high-speed centrifugation of intact platelets and fibrin in the absence of exogenous thrombin yields a potential tool for accelerating tissue repair.

The Cedar's wood of Atlas (Cedrus atlantica Manetti) coming from Djurdjura central forest, in Algeria, has been studied through the destructive method in three stations. These latters differ in density of population, exposure and nature of soil. In total, 54 young trees (32/48 years-old ; 4.5/7.9 cm diameter) were analysed, 18 trees in each station have been taken. The physical analyses done on (9 samples/tree) it means 486 normalized test-tube are: equilibrium of humidity, axial shrinkage, tangential shrinkage, volumetric shrinkage, anisotropy, infradensity and others parameters such as eccentricity index and of ring-width measurement. At this level of investigation, we notice that the cedar's wood presents a very low value of ring width, and the presence of very high compression wood ratio. This leads to the occurence of an important axial shrinkage and overdensity. At this stage, the Atlas cedar is characterized by high physical properties which are similar to those of old trees. Its wood presents medium shrinkage and less nervous and heavy wood. This analysis shows an effect of the station and the tree over the physical properties in particular on the axial shrinkage., Le bois du cèdre de l'Atlas (Cedrus atlantica Manetti) provenant de la cédraie du Djurdjura central, en Algérie, a fait l'objet d'une étude par une méthode destructive dans trois stations. Ces dernières se singularisent du point de vue de la densité du peuplement, l'exposition et la nature du sol. Au total 54 jeunes arbres (32 à 48 ans ; 4,5 à 7,9 cm de diamètre ), soit 18 arbres par station ont été prélevés. Les essais physiques entrepris sur 486 éprouvettes normalisées, soit 9/arbre sont : l'humidité d'équilibre, le retrait axial, le retrait tangentiel, le retrait radial, le retrait volumétrique, l'anisotropie, l'infradensité et d'autres paramètres tels que l'indice d'excentricité et la largeur des cernes. À ce niveau d'investigation, il ressort que le bois de cèdre étudié présente des largeurs de cernes très faibles et une présence de bois de compression élevée. Ceci a conduit à l'apparition d'importants retraits axiaux et une surdensité. Le cèdre de l'atlas, à cet âge de référence se caractérise par des propriétés physiques élevées comparables à celles des arbres adultes. Son bois est qualifié de bois à retrait moyen, peu nerveux et lourd. L'analyse montre un effet relatif de la station et de l'arbre sur les propriétés physiques notamment le retrait axial.

A detailed transport model is used to predict the effects of the widely variable physical properties (density, thermal conductivity, permeability to gas flow, specific heat capacity) of the feedstock on the convective-radiant pyrolysis of cellulosic fuels. For conversion in a thermally thick regime (intra-particle heat transfer control), it is found that variations in the physical properties mainly affect the activity of secondary reactions of tar vapours and the conversion time. The highest sensitivity is associated with the biomass density and the char thermal conductivity. Physical properties weakly affect only the conversion time in the thermally thin regime (external heat transfer control). Applications of these findings in reactor design and operation are discussed.