Percentage Of Absorption Research Articles

Selective double-layer on black Ni-P enhances solar absorption and reduces corrosion

This work investigates a double-layer configuration for the black Ni-P layers used in solar adsorption technology, aiming to increase the absorption of a broader range of solar wavelengths. This multilayer configuration has a surface with increased roughness and absorption area. The valleys were porous materials, which were connected to an underlying metallic sub-layer that is susceptible to corrosion. In turn, this corrosion induced changes to the top layer. The Ni-P layer was deposited by the electroless technique using an acid nickel sulfate bath as a source of metal ions and a reducing agent of sodium hypophosphite. Etching initiated an oxidation process on the surface, forming a layer of amorphous black nickel oxide for absorption. The surface features of the black Ni-P double layer consist of an uneven surface that aids sunlight adsorption. Carbon steel (AISI 1018) with different surface finishes was used for depositing Ni-P and black Ni-P, aiming to establish correlations with solar adsorption. The sample with an increased surface roughness obtained a higher absorption percentage than a single layer. The corrosion rate was calculated as 7 mmpy for the black Ni-P layer by applying polarization curves. A 6 µm-thick Ni-P double layer was obtained, achieving 96% absorption within the 300–2,000 nm range.

Development of Prediction Models for Compressive Strength in Cement Mortar with Bentonite Using Machine Learning Techniques

In this study, the effects of bentonite-blended cement mortar, cement strength, cement amount, slump values, water absorption percentages by weight, and porosity values on the 28-day compressive strength were investigated using MR (Multiple Regression), ANFIS (Adaptive Neuro-Fuzzy Inference System), and the intuitive optimization method known as PSO (Particle Swarm Optimization). Based on the results obtained from 18 data points, with 4 of them used for testing and 14 for training, effective and ineffective input parameters were identified in comparison to MR. Subsequently, PSO and ANFIS main models were designed according to the obtained results. As a result of the study, it was determined that cement strength, cement amount, and water absorption parameters have a higher impact on compressive strength compared to other parameters. It was found that the best accuracy model was achieved with the PSO model, and the results of the MR model can also be used in predicting outcomes.

Comparative investigation of mechanical properties in banana fiber and ramie fiber composites enhanced by SiC nanoparticles

This research explores into analyzing the mechanical characteristics of banana fiber and ramie fiber composites bolstered with silicon carbide (SiC) nanoparticles. The integration of SiC nanoparticles aims to amplify the mechanical robustness and endurance of these natural fiber composites. Through water absorption assessments, we evaluated the composites’ resistance to moisture. In addition, we assessed the mechanical performance via hardness, impact, and three-point bending tests. The results indicate a significant enhancement in the mechanical attributes of both banana and ramie fiber composites due to SiC nanoparticle inclusion. The results reveal a notable enhancement in mechanical characteristics following the incorporation of SiC nanoparticles. Notably, composites containing 8% SiC nanoparticles demonstrated the highest hardness value of 102 HV and the lowest water absorption percentage of 1.5%. In addition, these composites exhibited a superior flexural strength (80 MPa) and modulus of elasticity (4.3 GPa), alongside a maximum impact energy absorption of 18 J. These findings underscore the beneficial influence of SiC nanoparticles on the mechanical properties of the composites, including increased strength, reduced water absorption, enhanced hardness, and improved impact resistance.

Effect of Mordants on Percentage Absorption of Rubia Cardifolia Dye

This study examines the impact of various mordants on the absorption of Indian Madder Root dye by cotton fabric. The Indian Madder Root dye, derived from the roots of the Indian madder plant, is a natural, eco-friendly alternative to synthetic dyes. The mordants used in this investigation include ferrous sulfate, copper sulfate, zinc sulfate, magnesium sulfate, aluminum potassium sulfate, and potassium dichromate. The absorption of the dye was measured using a colorimeter at a wavelength of 680 nm. The results show that the transition metal mordants, such as copper sulfate and ferrous sulfate, exhibit the highest percentage absorption, while magnesium sulfate shows the least absorption. The study highlights the significance of mordants in enhancing the binding of dyes to fabric, resulting in improved colorfastness and retention of color. The findings of this research have implications for the textile industry, particularly in the development of sustainable and environmentally friendly dyeing processes.

The relationship between ceramic additives among structural, morphological, shielding, and stopping power features of BN/ZnFe metal matrix materials

Ionizing radiation has many negative effects on human health. These include eye and skin disorders and DNA damage inside cells. To eliminate or reduce these destructive effects of radiation, economical, low-corrosion, effective shielding materials with high absorption properties are needed. In this study, zinc-iron-based metal matrix composite materials with various proportions of boron nitride were produced on steel substrates. The structural and surface properties of the materials were examined with XRD and SEM images, respectively. These structures were irradiated with radioactive Am-241, Sr-90, Na-22, and Co-60 sources for their radiation shielding properties. Then, the absorption ratios in the samples were investigated according to the reinforced ceramic amounts in their content. In addition to the experiment, the stopping power and range values of the samples were calculated to check the reliability of the results. ZnFe alloys and composites are based on the dominant peaks of the heta (ƞ) phase of zinc. The amount of boron nitride added to the electrolyte significantly affected the crystal structure, while the incorporation of boron nitride into the zinc-iron matrix impressed the average grain size of the coating. The microstrain and dislocation densities of the film first decreased to 15 g/L and then increased depending on the ion diameter. The BN doping made the porous surface smooth, crack-free, and compact. It was found that the absorption rates for radiation increased as the amount of boron nitride in the samples increased. According to the rising amount of boron nitride, the absorption percentages are between 1.88 and 6.19% for alpha particles, 0.78–3.06% for electrons, 0.77–6.56% for positrons, and 0.61–6.34% for gamma photons. When the stopping power and range values were averaged, the amount of boron nitride increased directly and inversely with the stopping power and range values, respectively.

Utilization of Silica Fume and Sodium Hydroxide in Treated Crumb Rubber for Cement Mortar

Cement mortar offers an excellent replacement for materials such as fine aggregate with tire rubber waste in the form of crumbs. It provides excellent environmental and technical benefits to concrete production using recycled materials. As such, it contributes to the sustainable development of the construction industry. This paper mainly emphasizes the strength of untreated and treated crumb rubber from waste tires in cement mortar. Crumb rubber that has been pre-treated with Silica fume (SF) and sodium hydroxide (NaOH) to improve the strength of the mortar mix. This research used a cement-aggregate mix ratio of 1:4 and a water-cement ratio of 1:2. Five different percentages of fine aggregate replacement (0, 3, 6, 9, and 12%) was selected. The compressive strength, density, and water absorption of the mortar were measured at 28 days to find optimum strength. The compressive strength of the cement mortar mixed with treated crumb rubber showed significantly higher values, with an increase of 92% for 12% treated crumb rubber by sodium hydroxide (TN12) compared to untreated crumb rubber. The density value of the mortar cube mixed with treated crumb rubber decreased when the percentage of replacement for treated crumb rubber increased. In the application of roof tiles, lower density values provide an advantage for workability during installation. For water absorption, the treated crumb rubber contributes to a lower percentage of water absorption (acceptable until 6% for SF and 9% for NaOH) compared to the control sample as untreated crumb rubber. Therefore, a mixture of mortar with treated crumb rubber, especially NaOH solution, is better than the untreated crumb rubber specimen.

STUDY OF THE EFFECT OF MINERAL ADMIXTURE ADDITION ON PAVING BLOCKS' PHYSICAL AND MECHANICAL PROPERTIES

Paving blocks, concrete bricks made from cement and sand, are a vital alternative to ground cover. Their extensive, precast nature, water absorption capabilities, affordability, and ease of use contribute to their popularity. However, the additional ingredients, particularly mineral admixtures, hold the potential to enhance these blocks' quality and performance significantly. The mineral admixtures used, such as limestone, quartz sand, and gypsum, are instrumental in improving the performance of paving blocks, offering a promising avenue for further research and application. This research, conducted with meticulous scientific rigor, investigated paving blocks' physical and mechanical properties. Paving block test objects were created using sand, cement, and crushed stone with mineral admixtures. The mineral admixtures used in this experiment, including gypsum, quartz sand, and limestone, were crushed before being used in a stone cruiser machine to make them powder and reactive. Compressive strength test, weat resistance test, volume weight test, water absorption test, and visual inspection were conducted experimentally. The research results, derived from a robust experimental setup, revealed that paving blocks with 10% gypsum additives, 6% quartz sand powder, and limestone powder produced a more excellent compressive strength value than standard paving blocks, values of 36,884 MPa, 37,573 MPa, and 38,950 MPa with a regular paving block compressive strength value of 36,119 MPa followed by a decrease in the percentage of absorption. This suggests that using mineral admixtures at a certain percentage as an additional material can improve the quality of paving blocks. However, it is essential to note that adding too many mineral admixtures can also decrease the strength of the paving block, emphasizing the need for careful application of these materials in construction. These findings provide valuable insights for civil engineers, construction professionals, and researchers in materials science and construction technology, enhancing their understanding of the role of mineral admixtures in paving block strength.

Long-term properties evolution and life prediction of glass fiber reinforced thermoplastic bending bars exposed in concrete alkaline environment

Glass fiber reinforced polypropylene (GFRPP) bending bars have many advantages, such as high toughness, high durability, repeated molding and recycling, which can be used in concrete structures to replace steel stirrup for solving the problems of corrosion and service life. However, the changes in the properties of GFRPP bending bars during long-term use in alkaline concrete environments require further investigation. In the present study, GFRPP bending bars were immersed in alkaline solution at 20 °C, 40 °C, and 60 °C for as long as 180 d. The water absorption, hydrolysis, mechanical properties, and microscopic properties of the bending bars were evaluated to understand the long-term performance and mechanism of degradation. The bending bars had a higher saturated water absorption percentage and time along with a lower diffusion rate than the straight bars due to the presence of pores and micro-cracks formed during the bending process. The dissolution of the glass fibers in alkaline solution led to the partial mass loss of the GFRPP bars. Compared to the control, the tensile strength retention of the bending bars was 20.6%–56.0 %. The tensile failure mode changed from fiber bursting before immersion to shear fracture after immersion due to the decreased interfacial bonding strength and increased glass fiber brittleness. The primary degradation mechanisms were the etching of glass fibers, interface debonding, and increased void volume (∼23.7 %). The bending bars were more seriously eroded than the straight bars due to the twisting of the fibers and imperfect interfaces. The predicted degradation times of the GFRPP bending bars ranged from 1.7 years (Haikou) to 3.9 years (Harbin), corresponding to a stable tensile strength retention of 22.13 %. The results provide a basis for evaluating the durability and service life of GFRPP bending bars and promote the application of GFRPP composite stirrups in concrete structures.

Prediction of the First-Pass Metabolism of a Drug After Oral Intake Based on Structural Parameters and Physicochemical Properties.

The oral first-pass metabolism is a crucial factor that plays a key role in a drug's pharmacokinetic profile. Prediction of the oral first-pass metabolism based on chemical structural parameters can be useful in the drug-design process. Developing an orally administered drug with an acceptable pharmacokinetic profile is necessary to reduce the cost and time associated with evaluating the extent of the first-pass metabolism of a candidate compound in preclinical studies. The aim of this study is to estimate the first-pass metabolism of an orally administered drug. A set of compounds with reported first-pass metabolism data were collected. Moreover, human intestinal absorption percentage and oral bioavailability data were extracted from the literature to propose a classification system that split the drugs up based on their first-pass metabolism extents. Various structural parameters were calculated for each compound. The relations of the structural and physicochemical values of each compound to the class the compound belongs to were obtained using logistic regression. Initial analysis showed that compounds with logD7.4>1 or a rugosity factor of > 1.5 are more likely to have high first-pass metabolism. Four different models that can predict the oral first-pass metabolism with acceptable error were introduced. The overall accuracies of the models were in the range of 72% (for models with simple descriptors) to 78% (for models with complex descriptors). Although the models with simple descriptors have lower accuracies compared to complex models, they are more interpretable and easier for researchers to utilize. A novel classification of drugs based on the extent of the oral first-pass metabolism was introduced, and mechanistic models were developedto assign candidate compounds to the appropriate proposed classes.

Analisis Sisa Radiofarmaka Teknesium-99m MDP Pada Pemeriksaan Sidik Tulang Di Instalasi Kedokteran Nuklir

Bone cancer that has metastasized can be detected through a bone fingerprint examination, which involves the injection of tc-99m with the pharmaceutical Methylene Diphosphate (MDP). Bone prints are often used to trigger possible metastases of cancer to the bone, which is a major health problem for women worldwide. This study aims to activate the described organ uptake and residual radiopharmaceuticals in bone prints using the Region of Interest (ROI) method. The research was conducted on five datasets of patients with breast cancer. The patient received an intravenous injection of tc-99m MDP and, three hours later, underwent a bone fingerprint examination with a gamma camera. The image results from the gamma camera were processed using the ROI technique and analyzed further using statistical methods. The research findings showed that the five patients experienced an average reduction in residual radiopharmaceuticals of 2.965945119 mCi. Several factors, such as examination time, radiopharmaceutical dose, and body metabolism, influence the decay of radioactive activity in the body. The calculation of the absorption percentage for the five patients showed variations between 0.190070697% and 0.3510157519%

Sustainable production of eco-friendly roofing tile using methyl ester residue as the alternative binder – A preliminary study

Making full use of industrial by-products is an effort to achieve ‘zero waste’ and promote greener development. Methyl ester residue (MER) is a waste commonly found in oleochemical manufacturers, such as palm oil mills. Contrary to conventional cement and clay, MER was employed as an alternative binder to fabricate a novel eco-friendly roofing tile, henceforth referred to as MER-RT. Parameters tested were transverse strength, water absorption, sulfate resistance, and fire resistance. During the optimization phase, a range of 6–11% of MER was mixed with a fixed composition of fly ash and fine sand, compacted and cured at 190° C for 12–48 hours. Considering the electrical energy consumption, the optimal curing duration chosen was 24 hours as this MER-RT achieved a dry transverse strength of 4112 N whereas curing for an additional 18 hours further contributed to only 16% strength gain. The optimal MER-RT was found to contain 10% MER as it showed the highest dry transverse strength (6410 N), the highest wet transverse strength (3681 N) and the lowest water absorption percentage (2.67%), meeting the American Society for Testing and Materials (ASTM) standards. Besides exhibiting minimal corrosion under the sodium sulfate test, the optimal MER-RT was non-flammable and did not undergo structural changes when exposed to fire. The study reveals the potential of both MER and fly ash as green binders and fillers for roof tiles, despite their origins as industrial waste.

Investigation of TiO2 Nanoparticles Influence on Tensile Properties and Thermal Stability of Dry and Wet Luffa-Epoxy Nanocomposites.

Recently, progress has been made toward understanding the efficiency of polymer composites with natural fibres. With the hope of enhancing the characteristics of polymer composites supplemented with natural fibres in a watery environment, TiO2 nanoparticles have been used to improve their performance in the field. These nanoparticles were filled in luffa-epoxy components at 1, 3, and 5 % volume fractions. A combination of x-ray diffraction and Fourier transform infrared spectroscopy was utilized to conduct the structural examinations. The nanoparticle spread was captured by field emission scanning electron microscopy. Results show that dry nanocomposite's tensile strength and modulus have increased by 74% and, 13%, 137%, and 50% compared with epoxy and 40 vol% luffa-epoxy [E/L] composites, respectively. In wet nanocomposites, maximum reduction in tensile strength and modulus were observed as 27.4% and 16.54%, respectively. The diminished water absorption and thickness swelling percentage of nanocomposites were recorded as 98% and 91.8%, respectively. The onset temperature of these nanocomposites was scattered in the range of 379-393°C, with a maximum char residue of 38%. The increase in the percentage of residue indicates the effectiveness of epoxy's flame retardant, improved thermal stability, diminished water absorption [approximately 2%], and 95% retention of wet composites' tensile properties. These results provided data support for improving the application of nanocomposites in the automobile field.

Eco-Friendly Alternatives to Conventional Plastics – Finger Millet Based Soluble Food Folds

Introduction: Plastics are rendered as a symbol of this disengagement – a psychological and physical barrier between us and what we consume. People have been involved in preparing and consuming food folds since the 1900s. From the method of making a particular traditional sweet from Atreyapuram, Andhra Pradesh, this study attempted to create folds from ‘Ragi’. The main objective is to create soluble food folds that serve as a versatile bio-packaging unit that is 100% consumable and contributes to zero wastage, which the common womenfolk of community can prepare. Methods: Raw and germinated millets were processed to create edible folds. Subsequently, phytochemical and antioxidant analyses were conducted to evaluate the potential health benefits of the folds. Results and Discussion: Both the folds were relatively compatible to hold the dry contents inside. The highest percentage of scavenging activity is observed for aqueous extract of Germinated ragi fold (G), which scavenged 79.13 % radicals at a 100 μg/ml concentration. The low absorption percentage was expressed by an aqueous extract of Non- Germinated ragi fold (NG), which scavenged 5.22 % radicals at a concentration of 500 μg/ml. However, there is no significant difference between the phytochemical components between folds made from germinated ragi and non-germinated ragi. Conclusion: Edible food folds present a novel strategy for diminishing plastic waste and promoting eco-friendly food habits. Continued research could facilitate widespread acceptance, encouraging a greener approach to food packaging and consumption.

Assessment of Some Clay Deposits from the Gercus Formation (Middle Eocene) for Brick Manufacturing in the Dokan Area, NE Iraq

The objective of this research is to evaluate the suitability of some clay deposits from the Gercus Formation (Middle Eocene) in the Dokan area, Northeastern Iraq for brick manufacturing. Physical properties of the raw material including grain size analysis and Atterberg limits showed that composed mostly of sand and silt with a minor proportion of clay and classified as muddy sand. According to the plasticity chart, the studied sample plotted on the field of silt and organic clay with low plasticity. The geochemical analysis by X-ray fluorescence revealed that composed of a low percentage of silica and alumina and a high percentage of calcium oxide and magnesium oxide. The mineralogical analysis by X-ray diffraction showed that the studied samples were composed of non-clay minerals (dolomite, quartz, hematite, albite, anatase, and orthoclase) and clay mineral (montmorillonite, kaolinite, and illite). Twelve ceramic briquettes were prepared from the clay sample by semi-dry pressing method and pressed by 200 kg/cm² pressure with 14 – 15 % moisture content and fired at 880, 900, and 920 °C for evaluation tests of linear firing shrinkage, apparent porosity, water absorption, bulk density, efflorescence, and compressive strength. Results of physical and mechanical properties of the studied ceramic briquettes compared with the specification of Iraqi standard (1993) for clay brick manufacture, according to this specification the studied sample was not suitable for brick manufacturing due to a high percentage of water absorption and low compressive strength.

Wide-Aperture Backscattering Detector (BSD-A) for The High-Resolution Fourier Diffractometer

The high-resolution Fourier diffractometer (HRFD) has been in routine operation since 1994 at the long-pulse neutron source, the IBR-2 reactor, in Dubna. Its fast Fourier chopper provides probably the best compromise between very high resolution in reciprocal space (Δd/d ≈ 0.001) and the intensity. For further improving intensity of TOF-diffraction pattern, a wide-aperture ring backscattering detector (BSD) has been developed on the basis of ZnS(Ag)/6LiF scintillator. BSD is designed in the form of 6 concentric rings, each of which is subdivided into 12 identical parts. The main parameters of the detector are the following: range of scattering angles is 2θ = (133 - 175) degrees, covered solid angle is Ωd ≈ 2.0 sr, average percentage absorption efficiency gets closer to 85%, geometrical contribution to resolution function does not exceed Δd/d = 0.0005. In the report the concept of the detector is described and its data acquisition system is presented. The start of operation of the detector at the HRFD is scheduled for 2024.

Role of fibre weight fraction on low-velocity impact characteristics of abaca fibre reinforced bio-composites

This work involved an experimental study on Abaca fibre bio-composites subjected to a low-velocity impact test at 2.42 m/s to study the effect of fibre weight fraction on the impact performance. The abaca fibre reinforced composite (AFRC) specimens were fabricated with a 10% increment of fibre, varying from Wf = 20% to 50%, and their impact properties compared with each other. The impact properties such as force-time history, energy-time history, Coefficient of Restitution (CoR), Energy Loss Percentage (ELP) and Energy Absorption Ratio (EAR) were studied. A significant change in impact force and energy absorption was found as the fibre content increased in the composite. The findings show a good relationship between fibre weight fractions, composite laminate stiffness, impact load and total absorbed energy. The experimental results of the impact test show that the composite specimen with Wf = 40% has high impact energy absorption capacity with 4. 09 J 92.94 N and 4.09 J, EAR of 39.94%, CoR of 0.77 and ELP of 40.04%. Low fibre weight fraction composite has shown brittle failure, and high fibre weight fraction has shown ductile behaviour. Scanning electron microscopy (SEM) based study was used for post-impact damage analysis.

Physical and mechanical properties of mycelium-based fiberboards

Mycelium-based fiberboards were evaluated as potential environmentally friendly substitutes for conventional wood-based composites. The goal of this study was to produce and test fiberboards out of yellow pine and poplar fiber mixtures without using any extra adhesive. Pleurotus ostreatus and Ganoderma lucidum fungi were used. The physical and mechanical characteristics of the fiberboards were tested under the influence of two different types of fungi and two different incubation periods. The key findings indicated that the mycelium-based fiberboards had higher water absorption and thickness swelling percentages compared to control boards produced with adhesives. The fiberboards produced from fibers inoculated with Ganoderma lucidum and incubated for 30 days had higher mechanical properties compared to other test fiberboards. This indicated the possibility of utilizing them in specific applications. Although the mycelium-based fiberboards did not fully meet all the EN 622-5 (2009) standard requirements for dry-condition use, the results highlighted their potential in sustainable material development. This study provided useful insights into the utilization of mycelium for the development of mycelium-based fiberboards.

Herb–drug interactions: Quantitative analysis of levofloxacin absorption and transporter expression in the rat intestine following combined treatment with Persicaria capitata (Buch.-Ham. ex D. Don) H. Gross

Persicaria capitata (Buch.-Ham. ex D. Don) H. Gross, a traditional Chinese medicinal plant, is often used to treat various urologic disorders in China. P. capitata extracts (PCE) have been used in combination with levofloxacin (LVFX) to treat urinary tract infections (UTIs) for a long time. However, little is known about the absorption of LVFX and transporter expression in the intestine after combined treatment with PCE, restricting the development and utilization of PCE. In view of this, a UPLC-MS/MS method was established for the determination of LVFX in intestinal sac fluid samples and in situ intestinal circulation perfusate samples to explore the effect of PCE on the intestinal absorption characteristics of LVFX ex vivo and in vivo. To further evaluate the interaction between LVFX and PCE, western blotting, immunohistochemistry, and RT-qPCR were utilized to determine the expression levels of drug transporters (OATP1A2, P-gp, BCRP, and MRP2) involved in the intestinal absorption of LVFX after combined treatment with PCE. Using the everted intestinal sac model, the absorption rate constant (Ka) and cumulative drug absorption (Q) of LVFX in each intestinal segment were significantly lower in groups treated with PCE than in the control group. Ka at 2 h decreased most in the colon segment (from 0.088 to 0.016 µg/h·cm2), and Q at 2 h decreased most in the duodenum (from 213.29 to 33.92 µg). Using the intestinal circulation perfusion model, the Ka value and percentage absorption rate (A) of LVFX in the small intestine decreased significantly when PCE and LVFX were used in combination. These results showed that PCE had a strong inhibitory effect on the absorption of LVFX in the rat small intestine (ex vivo and in vivo intestinal segments). In addition, PCE increased the protein and mRNA expression levels of efflux transporters (P-gp, BCRP, and MRP2) and decreased the expression of the uptake transporter OATP1A2 significantly. The effects increased as the PCE concentration increased. These findings indicated that PCE changed the absorption characteristics of levofloxacin, possibly by affecting the expression of transporters in the small intestine. In addition to revealing a herb–drug interaction (HDI) between PCE and LVFX, these results provide a basis for further studies of their clinical efficacy and mechanism of action.

Switchable and tunable terahertz metamaterial absorber based on graphene and VO2 resonator with ultra-broadband and multi-band absorption

Vanadium dioxide (VO2) and graphene have been combined to create new design possibilities for high-performance metamaterial devices, which offer an alluring foundation for electromagnetic absorption applications. The structure under investigation, which is based on patterned graphene-vanadium dioxide and metamaterial absorbers, is capable of achieving both broadband and multi-band absorption. Also, the offered structure is tunable and switchable in the proposed wide-band range. We theoretically suggest a switchable and tunable graphene and VO2 resonator-based Broadband and Multi-band terahertz (THz) metamaterial absorber. The proposed absorber can achieve more than 99% absorption while operating in multi-band absorption mode at 2.26, 6.68, and 7.71 THz. Moreover, it can achieve absorption of more than 90% when operating in broadband mode, which has a bandwidth of 8.74 THz within the frequency range of 2.76–11.5 THz. In the 3.12–11.01 THz frequency band, this absorption percentage is 98%. The absorption spectra can be tailored by altering the chemical potential of the graphene layer and the conductivity of VO2. The suggested absorber also has a wide incidence angle insensitivity. As a result, the suggested absorber can be considered a good choice for various THz frequency range applications.

Technological quality of common bean landraces from organic cropping system

Beans are an important constituent of the Brazilian diet, and the search for cultivars with good culinary characteristics and adapted to the place of cultivation is necessary. It is known that there is a wide genetic diversity for common bean landrace cultivars. Still, little is known experimentally about the behavior of these cultivars when produced under organic cultivation. This work aimed to evaluate the technological quality of common bean landraces produced under organic cropping system. Twenty-six cultivars were used, four commercial and twenty-two landraces, originating from the Active Bean Germplasm Bank (BAF) of Santa Catarina State University – Agroveterinary Sciences Center (UDESC/CAV), produced in organic and conventional cultivation, in two crops. Cooking time and resistance, percentage of water absorption and broken grains and total soluble solids were evaluated. The shortest cooking time for the grains cultivated in the organic system (18 to 22 minutes) was obtained. The cultivars that had a percentage of unbroken grains between 60 and 80% showed a higher content of total soluble solids in the broth. Based on the genetic diversity for technological quality in organic cropping system, the use of cultivars, BAFs: 60, 23, 81, 13, 68, 55, 75 and 36 are indicated to integrate genetic improvement programs or to be used by small farmers for bean production.