Investigation of Sound Absorption Properties of Heat-Treated Indonesian Momala (Homalium foetidum (Roxb.) Benth.) and Korean Red Toon (Toona sinensis (A. Juss.) M. Roem.) Cross Sections

This study investigates the effects of heat treatment time and presence of an air back cavity on the sound absorption performance of Indonesian momala (Homalium foetidum (Roxb.) Benth.) and Korean red toon (Toona sinensis (A. Juss.) M. Roem.) cross sections. To examine the porous characteristics of the two species before and after heat treatment, gas permeability, pore size, and porosity analyses were conducted. Additionally, the sound absorption coefficient was measured based on various heat treatment times and air back cavity sizes. The results showed that, with heat treatment at 210 °C for 6 h, the gas permeability improved by 4.3% for the momala and 38.5% for the red toon, the maximum pore size was improved by 5.25% in the momala and 26.0% in the red toon, and the through-pore porosity improved by 22.7% for the momala and 117.0% for the red toon. Due to these pore structure changes, the noise reduction coefficient (NRC) of the heat-treated momala improved by 6.8%. When a 3-cm air back cavity was applied to the heat-treated momala, the NRC was improved to 92.5%. Similarly, when the same air back cavity was applied to the heat-treated red toon, the NRC was improved to 190.7%. This study demonstrated that an increase in pore size and through-pore porosity by heat treatment triggered an increase in the sound absorption coefficient. Additionally, when an air cavity was applied, the sound absorption coefficient of both heat-treated wood species was increased at low frequency. From the results of this study, we expected that heat-treated momala and red toon cross-sections can be utilized as eco-friendly ceiling materials with sound absorption function.

An Integrated Software for Computing Mechanical Properties of Crystalline Material by Means of XRD

An integrated software for calculating the major mechanical properties of materials was newly programmed. The material mechanical properties are determined from a peak position and the broadness of X-ray diffraction (XRD) line using profile function method, including Gaussian, Parabola, Half-width, and Centroid. The X-ray diffraction line in software is also corrected by the generalized X-ray absorption function. The results show that the precision coefficient (R2) of the dhkl-sin2 ψ linear regression depends on tested materials and the method of the 2θ determination. The Parabola and Gaussian methods show greater fitting accuracy in comparison to the other two methods in determining stress. The mechanical properties calculated using this software agreed well with the values determined from the conventional methods. In addition, this XRD software also allows computing the 95% confidential limits of the results from a single measurement without conducting repetitive measurements. Therefore, the new software allows widening the experimental scopes of an X-ray diffraction device in both laboratories and the industrial sector.

Modeling laser-induced incandescence of Diesel soot—Implementation of an advanced parameterization procedure applied to a refined LII model accounting for shielding effect and multiple scattering within aggregates for $${\varvec{\alpha}}_{{\varvec{T}}}$$ and $${\varvec{E}}\left( {\varvec{m}} \right)$$ assessment

An extensive set of LII signals measured in a Diesel spray flame has been simulated using a refined LII model built upon a comprehensive version of soot heat- and mass-balance equations. This latter includes terms standing for saturation of linear, single- and multi-photon absorption processes, cooling by sublimation, conduction, radiation and thermionic emission in addition to mechanisms depicting soot oxidation and annealing, non-thermal photodesorption of carbon clusters as well as corrective factors allowing considering shielding effect and multiple scattering (MS) within aggregates. A complete parameterization of the so-proposed model has been achieved by means of an advanced optimization procedure coupling design of experiments with a genetic algorithm-based solver. Doing so, the values of different factors involved in absorption and sublimation terms have been assessed for a 1064-nm laser excitation wavelength including the multi-photon absorption cross section for C2 photodesorption and the saturation coefficients for linear- and multi-photon absorption, among others. This parameterized model has then been demonstrated to effectively reproduce signals measured in different combustion media including a CH4/O2/N2 premixed flat flame and a diffusion ethylene flame. As a result of the data derived from the analysis of the Diesel flame, a thermal accommodation coefficient value of 0.49 has been assessed against 0.34 when neglecting the shielding effect. In addition, values of the soot absorption function ($$E\left( m \right)$$ E m ) comprised between 0.18 and 0.31 have been inferred depending on the particle maturation stage. On the other hand, $$E\left( m \right)$$ E m 24% higher on average have been estimated when neglecting MS thus illustrating the importance of aggregate characteristics on soot properties derived through LII modeling. Eventually, the $$E\left( m \right)$$ E m evolution observed herein has been compared with results issued from studies conducted with varied hydrocarbons which led to highlight the crucial role played by the soot maturity level over the nature of the burnt fuel as far as optical properties are concerned.

Not all superabsorbent wound dressings are born equal: theory and experiments

Among the advanced wound dressing types, superabsorbent (SA) dressings form an important class of dressings, particularly for the management of medium to highly exuding wounds. However, SA dressings are not all made the same. This educational article describes distinct, common SA dressing designs, which differ fundamentally in structure and composition, and, thereby, in their exudate absorption function and clinical efficacy. The diverse design families of SA dressings, including dressings with an SA polymer-sheet core, versus dressings with an air laid core, where the SA polymer grains are embedded in fluff, relate to different manufacturing processes, production techniques and associated fabrication costs. These fundamental structural and material differences across SA dressing designs from different manufacturers naturally lead to wide variations in the fluid handling characteristics of the products, which are analysed here using both theoretical and experimental bioengineering laboratory approaches. This work is primarily aimed at promoting critical thinking among health professionals who should ask manufacturers to present relevant testing data for an informed clinical decision-making with regards to the choice of the safest and best performing SA dressing for each treated wound case.

The Effect of Chicken Spleen Transfer Factor on Intestinal Mucosa Immunity Barrier of Laying Hens

Chicken spleen Transfer Factor (TF) is a low-molecular-weight lymphocyte extract composed of polypeptide and nucleotide. However, its role in regulating intestinal structure and function in laying hens has remained largely unknown. 100 one-day-old laying hens were randomly divided into five groups and administered with different doses of TF (0.00 [control], 0.05mL, 0.10mL, 0.25mL and 1.00mL). The results showed that the high dose of TF (1.00mL) improved the intestinal mucosa morphology and strengthened the digestive and absorption function. Furthermore, the histology analysis revealed an increase in the number of intraepithelial lymphocytes and goblet cells. Similarly, the results from ELISA demonstrated an increase in the content of IL-10 in the intestinal tract, while the content of TNF-a showed a decrease in this regard. The RT-PCR assay also demonstrated the upregulation of the relative mRNA expressions of Muc2, TLR-2, and TLR-4 genes. The intestinal antioxidant function was significantly enhanced. In conclusion, high-dose of TF can improve the intestinal mucosa morphology and structure, enhance digestion and absorption functions, enhance the intestinal mucosal barrier immune function and antioxidant function, and up-regulate Muc2, TLR-2 and TLR-4 gene relative expression.

Sustainable Forest Management Evaluation Using Carbon Credits: From Production to Environmental Forests

The biodiversity and carbon dioxide absorption function of forests have received attention due to global warming. However, most of the world’s forests are general production forests. Since production forests are maintained by production activities, a decrease in production or abandonment of management leads to a decline in forest functions and increases the risk of disasters such as landslides. Against this background, the retention approach has been proposed as a way to convert general production forests into forests with enhanced environmental functions, but it has rarely been applied due to technical and cost barriers. This study focuses on cost barriers and examines the possibility of introducing a retention approach to converting production forests to environmental forests, using Japan as a case study. About 70% of Japan’s land area is covered with forests, 40% of which are production forests. However, due to the sharp decline in demand for timber in recent years and price competition with imported timber, the selling price of timber has fallen below the cost of managing production forests, and the management of many production forests has been abandoned. The dilemma is that the retention approach applied to the wood production process cannot be applied to forests where production activities are stagnant. Therefore, we explored the possibility of recovering the necessary costs with carbon credits that are available in the Japanese market. We calculated the cumulative carbon stocks of carbon dioxide in production forests by age, using intensity, and estimated how many years after planting the combined costs of normal production forests management and the retention approach would balance out. Our calculations show that even if carbon credits were sold at the lowest market price, the balance of payments would be balanced about 30 years after planting, resulting in a net profit from the sale of the wood.

The effect of herbal supplements on development of internal organs and chemical composition of broilers muscles

The present article presents data on effectiveness of adding a phytobiotic feed additive into the diet of broiler chickens, either additionally or replacing the feed antibiotic in the chicken fodder. It has been established that the introduction of a phytobiotic feed additive into the broilers’ diet, both additionally and by replacing the feed antibiotic, provided positive effect on poultry meat quality and gave no negative effect on development of internal organs. By the end of fattening the relative weight of heart, lungs, kidneys, gizzard and intestines in broilers, which consumed the antibiotics-free diet with addition of researched preparation, was higher than in the control group and in the 1st experimental group. At the same time the length of the intestine in researched group significantly exceeded the control group parameters. These changes ranged within the physiological norm, which may indicate the best detoxification capabilities of the chicken body and the activation of enhanced intestinal absorption function. Additional use of the experimental feed additive in formulation of feed for broiler chickens was accompanied by a decrease in total amount of amino acids in broilers’ pectoral and leg muscles within acceptable physiological limits. At the same time, a significant decrease, compared with the control parameters, was noted in relation to content of histidine and isoleucine in pectoral muscles, and content of proline in leg muscles. The use of the researched additive as a substitute for a feed antibiotic in composition of mixed feed for broilers decreased the total amount of amino acids in broilers’ breast muscle, compared with the control group, and increased level of amino acids in leg muscles. The significant decrease in content of histidine and arginine in the pectoral muscles and proline in the leg muscles was noted. The observed changes varied within acceptable physiological norm. In the experimental groups the energy value of meat was increased.

A Nonreciprocal Angular Selective Absorber with the Special Multilayer Structure

Due to the orderly design of the special anti-reflection structure and the absorption structure, the one-dimensional layered periodic structure has a good impedance matching in a certain frequency band and a large-angle range, providing for the realization of an angular selective absorber (ASA) with a high rectangle coefficient. For the sake of obtaining excellent absorptivity, the indium tin oxide (ITO) film is used, and it also acts as a function of tuning the absorption angle range (AAR) of the ASA by adjusting the plasma frequency. The proportional relationship between the thickness of the dielectric layers is also discussed to satisfy a good absorption function. At the same time, the ASA also possesses productive nonreciprocal performance (NP) and can also be controlled by the plasma frequency. The transfer matrix method is used for numerical simulation. Our special tunable ASA with the NP is relatively rare in previous studies, which can be applied to optical communications and military fields. Furthermore, we hope that the design we proposed can provide new possibilities for the development of the ASAs.

Local Form of Loss of Stability of Honeycomb Energy Absorber Plates

Landing devices perform the energy absorption function during the spacecraft motion. Precise analytical solution to the problem of stability of a lengthy plate with free edge exposed to the edge compressive load was obtained in order to analyze operation of the honeycomb materials used in structural elements absorbing the moving bodies energy. General solution analysis of the differential equation for a lengthy plate bending in the deflected position was carried out, and general solution is subjected to the boundary conditions corresponding to the loaded free edge. Critical load value and form of the loss of stability were determined. Critical load identified value was significantly lower than the critical load for a plate supported on the loaded edge. The loss of stability identified form was characterized by sharp deflection localization near the loaded edge and could create conditions for forming a local fold near the loaded edge. Obtained analytical solution was verified by comparing it with results of the similar numerical solution. Comparison performed revealed satisfactory agreement both in the critical load value and in the form of loss of stability for two solutions obtained by different methods. The results obtained could be used in designing energy absorbers made of honeycomb materials, as well as in other areas of technology