Lower Water Absorption Capacity Research Articles

The addition of sugarcane bagasse and asparagus peel enhances the properties of sweet potato starch foams

The agro‐industrial wastes, sugarcane bagasse (SB) and asparagus peel (AP), were used to enhance the properties of biodegradable foam trays based on sweet potato starch‐based foam trays (starch/SB and starch/AP trays, respectively). Starch/SB and starch/AP trays containing different concentrations of SB and AP (0%‐40%, w/w) were prepared, and their microstructure and physical, thermal, and mechanical properties were characterized. The addition of fibers wastes allowed obtaining a yellowish foam tray with lower luminosity and higher porosity, mechanical resistance, deformability, and better ability to absorb water as compared with the sweet potato starch foam trays without fibers. The addition of SB yielded foam trays less porous, with lower water absorption capacity and greater tensile strength than the addition of AP. Higher concentrations of AP fibers (greater than 30%) generate more extendible foam trays. The addition of fibrous wastes improved the thermal stability of the sweet potato starch foam trays. The composite foam trays produced in this work could be used as substitutes for expanded polystyrene in dry food packaging.

Analysis of Development Block Paving with Plastic Waste Material Adhesive Leaves

Plastic waste remains a major problem in Indonesia, however, it’s processing and utilization is currently very limited, especially in the construction sector. In addition, they are possibly divided into two categories, which include (1) Plastic garbage, which consists of bottles container for mineral water, soap, and oil, as well as oil conductors, buckets, e.t.c. (2) leaf of plastic waste, encompassing bags, food wrappers, mica snack. Furthermore, one of the famous construction materials is the paving block, used as the cover for pavement surfaces, usually characterized by good quality, with a high value of compressive strength and low water absorption capacity. This research, therefore, was conducted with experimental methods, using plastic waste leaves as an adhesive in the manufacture of paving blocks with varying mixtures C1 (2 plastic: 1 sand), C2 (3 plastic: 1 sand), C3 (5 plastic: 1 sand), C4 (9 plastic: 1 sand), and C5 (11 plastic: 1 sand). In addition, tests were conducted by the Indonesian National Standard (SNI), and the results showed the optimum mixture was C5 (11 plastic: 1 sand), based on the compressive strength of 246.93 kg / cm2, and water absorption value of 2.23%. Hence, it is categorized into quality B, which is possibly applied in parking space construction. This, therefore, indicates the capability of applying plastic waste leaves, with a certain mixture variation as an adhesive in the manufacture of paving blocks.

Effect of Sand on the Properties of Compressed Soil-Cement Stabilized Blocks

With the growing concern of awareness regarding sustainable building materials and environmental issues, a number of people have resorted to using soil-cement stabilized blocks (SCSBs) as an alternative for burnt bricks. However, these stabilized blocks are also known for their high-water absorption capacity during wet seasons which affects their strength and durability. The study conducted involved a series of physical properties tests of soil (particlesize distribution analysis and Plasticity Index test); mechanical property tests (compressive strength test and water absorption test), which were undertaken in accordance with the ASTM standard. It compared the compressive strengths and water absorption capacity amongSCSBs with a sand blend at different proportions of mixture (10%, 20% and 30%) and those without sand, maintaining thequantity of cement constant at 5%. The results indicated that the compressed stabilized earth blocks using silty clay soil blended with sand and with 5% cement were stronger compared to those without sand. However, the water absorption capacity of the blocks (both with and without sand), revealed no significant difference except for the blocks with 20% of sand which proved to have the lowest water absorption capacity (15%). The SCSBs of 10% addition of sand proved to be the strongest with compressive strength of 2 Mpa. The study concluded that 10% blend of sand could be adopted in block manufacturing for sustainable low-cost housing construction. Having known the strength of these blocks, the users can go ahead and use them in low cost housing construction projects.

Biodegradable plastic designed to improve the soil quality and microbiological activity

Biodegradable plastic composites were produced from mixtures of polyvinyl alcohol (PVA) and starch, which were mixed with different natural fillers [sugarcane bagasse (SB), oat hulls (OH) or silkworm exuvia (SE)] and nutrients to stimulate the biodegrading microbiota. The physicochemical and biodegradability characteristics of the produced materials were studied, in addition to their influence over the microbiota involved in biodegradation. The SB-composite showed reduced solubility in water, a lower water absorption capacity and a slower mineralization rate when buried in a commercial substrate for seedlings production, as compared with those of the OH- and SE-composites. Scanning electron micrographs demonstrated the increased colonization of materials by the biodegrading microbiota over time, which were predominated by filamentous fungi in OH- and SE-composites, while the SB-composite was predominantly colonized by bacteria. A Fourier transform-infrared spectroscopy (FT-IR) analysis of the biodegraded materials highlighted the chemical differences in the protein and carbohydrate content between formulations, corroborating the activity of different microbial groups on their mineralization. Regardless of its composition, the mineralization rate of the materials was positively correlated with the microbial biomass carbon (C mic) and basal respiration (RB) of the substrate. However, the correlation between the mineralization rate and the metabolic quotient of the substrate (qCO2) was negative for the OH- and SE-composites, while the SB-composite showed no significant correlation among these variables. The differences observed in the formulations indicated that biodegradable plastics can be designed for a given goal by selecting the most appropriate formulation.

A Study on the Pozzolanic Properties of Pennisetum Purpureum Ash

Pozzolanic properties of Pennisetum purpureum grass ash were tested on Portland cement. Results show that the ash can be blended with cements without compromising binding strength of the cement. It was found that Portland cement could be blended with Pennisetum purpureum up to a ratio of 3:2 compromising compressive strength of mortar.Mortar with lower cement replacement took longer to set as evidenced by lower compressive strength within the 28-day aging time. Mortar with higher cement replacement had lower water absorption capacity, an indication that the test pozzolan was of smaller particulate size. XRF analysis and the FTIR spectrum showed that the ash has a higher content of silica. The XRD pattern of the ash showed that the ash was predominantly amorphous. SEM images showed that the ash produced at 600 o C had residual carbon material.

Optimization of Extrusion Variables for Improving the Qualities of Textured Vegetable Protein with Green Tea Using Response Surface Methodology

The aim of this study was to evaluate the optimization extrusion variables on quality of textured vegetable protein by using response surface methodology. In this study, 50% soy protein isolate, 40% wheat gluten, and 10% corn starch were blended and 15% of the mixture was substituted with green tea. The moisture content (45, 50, and 55%), barrel temperature (130, 140, and 150oC), and screw speed (100, 150, and 200 rpm) were varied. A Box- Behnken design was used in this experiment. Second order polynomial regression equations were developed to relate the response to extrusion variables as well as to obtain a response surface plot. The independent variables had significant effects on the quality of the products and moisture content was the most significant. The lower moisture content led to the higher integrity index, lower nitrogen solubility index, lower water absorption capacity, higher texture, and higher cutting strength. The optimum conditions were identified as moisture content 47.78%, barrel temperature 150.00oC, and screw speed 196.05 rpm. Incorporation of green tea into protein materials could effectively improve the nutritional value of the product. Understanding these optimized extrusion variables on the product quality was useful for producing textured vegetable protein in the future.

Effect of Pullulan and Hydrocolloids on Rheological Properties and Quality Parameters of Wheat-Soy Baladi Bread

Baladi bread is a staple food in Egypt and high nutritive value however, stales rapidly. The aim of the study was to conduct a comparative evaluation of pullulan and hydrocolloid combinations on rheological properties and quality parameters of wheat-soy baladi bread. Pullulan polysaccharides (Pu) and hydrocolloids as Arabic gum (AG), K-carrageenan (KC), pectin (P), and xanthan gum (XG) were applied. Rheological properties of samples included Pu and hydrocolloids were analyzed through extensiograph and farinograph. The crust color, staling, and sensory attributes of bread were evaluated. Results revealed that wheat flour (WF) has lower water absorption capacity, dough development time, mixing tolerance index, and resistance to extension however, has higher dough stability, extensibility, and dough energy compared to wheat-soy flour (WSF). Pu and/or hydrocolloids addition to WSF dough evidently improved bread quality. Pu was significantly enhanced crust color and yielded fresher bread relative to control. Additionally, Pu showed the highest Alkaline Water Retention Capacity (AWRC) value after 5 days at 25°C ± 2°C. Results demonstrated that hydrocolloids especially pullulan can significantly improve dough properties, baking quality, sensory acceptability, and delay staling of wheat-soy baladi bread.

Adsorption of aquaculture pollutants using a sustainable biopolymer.

Intensive aquaculture needs to adopt techniques that are able to contribute towards sustainability. Closed systems that employ water recirculation can combine intensive production with environmental sustainability, since there is no exchange of water or discharge of effluents into the environment. In order to achieve this, effective filtration systems are required to ensure that the water quality is satisfactory for the cultivation of aquatic organisms. Chitosan, an industrial waste material derived from crustacean farming, is a renewable natural material that is biodegradable and possesses adsorbent characteristics. In this work, chitosan foam was incorporated in filters and was evaluated as an adsorbent of aquaculture pollutants, adding value to the material and at the same time providing a use for industrial waste. The foam was characterized by scanning electron microscopy and energy dispersive spectroscopy, apparent density, and water absorption capacity. It was used to remove ammonia, nitrite, orthophosphate, and turbidity from aquaculture effluents. The foam consisted of a bilayer with smooth and porous sides, which presented low density, flexibility, and high water absorption capacity. The best proportion of the foam, in terms of the mass of foam per volume of solution (%mv-1), was 0.10, which resulted in removal of 32.8, 57.2, 89.5, and 99.9% of ammonia, nitrite, orthophosphate, and turbidity, respectively. This biopolymer produced is biodegradable, and when saturated with organic compounds from aquaculture, and no longer suitable for reuse as a filter material, it can be employed as a fertilizer, hence closing the sustainability cycle of the aquaculture production chain.

Native and microwave-modified Terminalia mantaly gums as sustained-release and bioadhesive excipients in naproxen matrix tablet formulations.

Hydrophilic polymers provide a means of sustaining drug delivery. Native gums may be limited in function, but modification may improve their activity. The aim of the study was to evaluate native and modified forms of Terminalia mantaly gum for their sustained-release and bioadhesive properties. The native gum (NTM) was modified by microwave irradiation for 20 seconds (MTM20) and 60 seconds (MTM60) and characterized using microscopy, Fourier transform infrared spectroscopy (FTIR) and packing properties. The effects of the thermally induced molecular reorientation were determined. Tablet formulations of naproxen were produced by direct compression. The mechanical, bioadhesive and release properties of the formulations were determined. Irradiation of NTM improved the gum's flow properties, resulting in Carr's Index and Hausner's ratios lower than 16% and 1.25, respectively. Swelling studies showed that MTM20 and MTM60 had lower water absorption capacity and swelling index values, while packing properties improved upon irradiation, as depicted by lower tapped density values. FTIR spectra of samples showed that the irradiated gums were distinct from the native gums and did not interact with naproxen sodium. The gum's mechanical properties improved with MTM20 and MTM60 and sustained-release action of up 12 h was obtained. Inclusion of hydroxypropyl methylcellulose (HPMC) in the tablet formulations proved critical for bioadhesion. Microwave irradiation of native Terminalia mantaly gum improved the flow, mechanical and sustained-release properties of Naproxen tablets, and the addition of HPMC increased bioadhesion properties. The tablet properties of the native gum were significantly improved after 20 s of microwave irradiation.

Plate Water Absorption as an Assessment Tool for Organic Binders

ABSTRACTPlate water absorption has been traditionally used to assess the binding ability of bentonite clay binders for iron ore concentrate pelletization. Until 1997, there was an accepted test by ASTM, but due to inconstant data this method was withdrawn. This value, however, is still used by some pelletization operations to gauge the efficacy of their bentonite. This test procedure has only been investigated on inorganic binders and never organic binders. This paper seeks to confidently prove that PWA can be used to accurately determine the efficacy of starch binders both alone and in conjunction with bentonite. The role of bentonite as a binder for iron ore concentrate is not only to hold agglomerates together during high temperature operations. But during pelletization it can also mitigate many times its own weight in water. This water absorption capacity aids in retarding the growth rate of pellets, as faster growing pellets tend to be weaker. The value of this water absorption, known as plate water absorption (PWA), is used as a metric to determine the strength and quality of the resulting pellets by industrial pelletizing facilities. As new low silica binders seek to replace bentonite, they too must take on the role of moisture mitigation. This study has shown that starches with lower water absorption capacities tend to have lower compressive strengths. As the water absorption capacity increases so too does the compressive strength. When using only starch, higher absorption capacities lead to lower compressive strengths of pellets exposed to elevated temperatures. When bentonite is used in conjunction with starch, higher water absorption mixtures do exhibit an increase in strength when heated.

銅・マンガンスラグ細骨材およびフライアッシュを用いたコンクリートの乾燥収縮ひび割れ抵抗性

Drying shrinkage is inevitable in concrete mixtures when exposed to dry environment. This is not only dependent on hardened cement paste comprising the types of cement and water content, but the properties of aggregates including water absorption capacity and elastic modulus. Generally, materials design with respect to enhance the resistance against drying shrinkage cracking aims at higher strength development and reduced drying shrinkage, which can be obtained by lower water content and the proper use of cement and mineral admixtures in concrete mixtures and the use of aggregates with lower water absorption capacity and higher elastic modulus. This study examined the resistance against drying shrinkage cracking in concrete mixtures mixed with two types of slag fine aggregates (copper and manganese slag) and fly ash, which was investigated using restrained reinforced concrete specimens. The results showed that the cracking resistance was enhanced in concrete mixtures mixed with copper slag fine aggregate and fly ash, which could be explained by the fact that the restrained stress was partially relaxed during the early stages of exposure to dry environment. In addition, fresh properties including slump, air content and bleeding rate were also tested for practical application.

Properties of baked foams from oca (Oxalis tuberosa) starch reinforced with sugarcane bagasse and asparagus peel fiber

The aim of this work was evaluate the effect of the addition of sugarcane bagasse and asparagus peel fiber on the physical and mechanical properties of baked foams based on oca starch. Low concentrations of fiber reduce the density of the foams and the addition of fiber does not improve the flexural strength of the foams, but generates harder and deformable trays. High concentrations of sugarcane bagasse fiber generate more compact trays with a lower water absorption capacity than the control. Foams with asparagus peel fiber showed higher rates of thermal degradation than the control but not so extensive as to affect their applicability.

Effects of pyroconversion and enzymatic hydrolysis on indigestible starch content and physicochemical properties of cassava (Manihot esculenta) starch

Cassava (Manihot esculenta Crantz) root is the second most important starch source worldwide and its cultivation could be potentially much greater. Pyrodextrins and enzyme-resistant maltodextrins were produced from cassava starch by pyroconversion and enzymatic hydrolysis. Changes in indigestible starch content and some physicochemical properties were analyzed. The best results were produced with a 160:1 (m/v) starch:HCl ratio, 90°C temperature, and 3 h reaction time. These conditions produced a pyrodextrin with 45.98% indigestible starch content and a color difference of 1.89. Optimum hydrolysis conditions were a 0.01% α-amylase concentration and 5 min reaction time, which produced a resistant maltodextrin with 24.45% dextrose equivalents and 56.06% indigestible starch content. Compared to the native starch, the pyrodextrin exhibited 93% solubility at 60°C, and 100% at 70–90°C. The resistant maltodextrin was completely soluble at all temperatures. The pyrodextrin had low water-absorption capacity (0.16–0.34 g water/g gel) and some swelling power, while the resistant maltodextrin had neither property, even at low temperatures. None of the compounds exhibited a gelatinization transition. The resistant maltodextrin's high indigestible starch content and solubility make it a promising ingredient for increasing dietary fiber content in a wide range of foods, particularly beverages, creams, soups, dairy and bread products.

Properties, durability and use of glauconitic Godula sandstones: a relatively less known building stone of the Czech Republic and Poland

Greenish glauconitic sandstones from the Middle Member of the Godula Formation of the Outer Western Carpathians flysch belt represent traditional building stone used in the north-eastern part of the Czech Republic and adjoining part of south Poland for about a thousand years. Despite the longstanding history of their utilisation in constructions and monuments, the amount of information about properties, durability and places of use is given in the existing literature only to a very limited extent. The Godula sandstones under study exhibit a high bulk density (up to 2610 kg/m3), relatively low water absorption capacity (0.7–3.0 wt%) and total porosity (1.7–9.4%), high values of P-wave velocity within psammitic rocks (3120–4290 m/s), and high to very high strength (uniaxial compressive strength 102.7–155.8 MPa, splitting tensile strength 4.0–10.0 MPa). However, in contrast to high quality of stone properties, the degree of their durability especially in the case of exterior use may often be very low, and stone deterioration can frequently advance very rapidly. Godula sandstones are characterised by a significant dominance of pores with diameter smaller than 1 μm. The character of pore space represents the principal and general reason of Godula sandstone deterioration susceptibility. Deterioration rate and specific weathering forms are subsequently strongly affected, in detail, by the heterogeneity of the mineralogical composition and anisotropy of rock texture within the individual sandstone bed. The data about composition, properties and stability of the Godula sandstones published in this paper could help architects or designers to understand the decay causes experienced by these types of sandstones and how to prevent them and may also serve as a guide for restoration and conservation works.

Physico-Chemical Characterization Of Sweet Chestnut (Castanea Sativa L.) Starch Grown In Temperate Climate Of Kashmir, India

Studies were conducted to characterize the chestnut starch for physico-chemical properties. Chemical composition of chestnut starch showed low levels of protein and ash indicating purity of starch. The results revealed low water and oil absorption capacity of chestnut starch. Starch showed high swelling power and low solubility index. Swelling power and solubility index of chestnut starch increased with increase in temperature (50–90 °C). The results revealed high initial, peak, setback, breakdown, and final viscosity but low paste development temperature. Transmittance (%) of the starch gel was low and decreased with increasing storage period. The chestnut starch gel showed increase in % water release (syneresis) with increase in time of storage but was less susceptible to repeated cycles of freezing and thawing. Starch was also characterized for granule morphology. Starch granules were of round and oval shapes, some granules showed irregular shape.

Synthesis of waterborne polyurethane-urea dispersions with chain extension step in homogeneous and heterogeneous media

HypothesisThe possibility of tailoring the final properties of environmentally friendly waterborne polyurethane and polyurethane-urea dispersions and the films they produce makes them attractive for a wide range of applications. Both the reagents content and the synthesis route contribute to the observed final properties. ExperimentsA series of polyurethane-urea and polyurethane aqueous dispersions were synthesized using 1,2-ethanediamine and/or 1,4-butanediol as chain extenders. The diamine content was varied from 0 to 4.5wt%. Its addition was carried out either by the classical heterogeneous reaction medium (after phase inversion step), or else by the alternative homogeneous medium (prior to dispersion formation). Dispersions as well as films prepared from dispersions have been later extensively characterized. Findings1,2-Ethanediamine addition in heterogeneous medium leads to dispersions with high particle sizes and broad distributions whereas in homogeneous medium, lower particle sizes and narrow distributions were observed, thus leading to higher uniformity and cohesiveness among particles during film formation. Thereby, stress transfer is favored adding the diamine in a homogeneous medium; and thus the obtained films presented quite higher stress and modulus values. Furthermore, the higher uniformity of films tends to hinder water molecules transport through the film, resulting, in general, in a lower water absorption capacity.

Characteristics of fired bricks with co-combustion fly ashes

This paper studies the feasibility of utilizing co-combustion fly ashes for the production of eco-friendly fired bricks. The fly ashes from co-combustion of coal and pet coke in a Spanish Power Plant were used as raw material to replace clay to make fired bricks. The effect of fly ash with high replacing ratio (from 0 to 80%) of clay on properties of bricks was analysed. The specimens, cylinders with 32.5mm diameter and 50mm length, were manufactured by compressing at 10MPa. Different firing temperatures, 800, 900 and 1000°C, were studied. The fired bricks with high volume ratio of fly ash present a high compressive strength and a low water absorption capacity. With increase in firing temperature, the compressive strength increased and the water absorption decreased. With increase in replacing ratio, the compressive strength decreased and the water absorption ratio increased. The bricks no present environmental problems according to the leaching study.

Zoneamento agroclimático de amendoinzeiro para a Bacia do Alto Paraguai (MT)

RESUMO O sucesso de uma agricultura tecnificada, produtiva e sustentável é obtido por meio do conhecimento do clima e solo da localidade, combinado com o seu adequado manejo. Este estudo objetivou determinar o zoneamento agroclimático da cultura do amendoim para a região da Bacia do Alto Paraguai, no Estado de Mato Grosso, identificando os municípios que apresentam aptidão para a exploração dessa cultura e estabelecendo as épocas para a sua semeadura. Foram analisadas as condições edafoclimáticas da região, respeitando-se o ciclo (90-120 dias) e as exigências hídricas (400-600 mm) da cultura. Para os tipos de solos classificados de acordo com o teor de argila, foram determinados a capacidade de armazenamento de água (CAD) e o índice de satisfação e necessidade de água (ISNA). Concluiuse que todos os municípios que cultivam amendoim apresentam mais que 50 % de solo tipo CAD 75, com mais de 35 % de argila (Arenápolis, Barra do Bugres, Indiavaí, Lambarí D’Oeste, Nova Olímpia, Rondonópolis, São José dos Quatro Marcos e Tangará da Serra). Esse tipo de solo favorece o cultivo tardio, que pode ser realizado até o 7º decêndio. Já para os solos tipo CAD 30, com menos de 15 % de argila, o cultivo só deve se iniciar a partir do 6º decêndio, por apresentarem baixa capacidade de absorção de água.

Effect of Soaking African Yam Bean Seeds in Unripe Plantain Peel Ash Solutions on the Nutrients, Anti-nutrients and Functional Properties of the Flour

The dark brown coloured variety of African yam bean seeds (Sphenostylis stenocarpa) were soaked in distilled water (control) and in 1,2,3,4 and 5% solutions of unripe plantain peel ash (1:3w/v) for 15h at room temperature (27+0C), decorticated and processed into flours. The effects of soaking the seeds in different concentrations of the ash solution on proximate, mineral and anti-nutrient composition as well as on the functional properties of the flours were investigated. Result showed that the treatments had varying effects on the parameters evaluated. Flours prepared from seeds that were soaked in ash solutions had significantly (p 0.05) higher swelling index and marginally (p>0.05) lower water absorption capacity and bulk density than the flour from seeds that were soaked in water. It is evident from the study that soaking African yam bean seeds in unripe plantain peel ash solutions has beneficial effects as the flours prepared from the soaked seeds had higher levels of protein and mineral elements, lower levels of anti-nutrients and the functional properties were not impaired when compared with flour from seeds that were soaked in water.

Comparison of Bio and Eco-technologies with Chemical Methods for Pre-treatment of Flax Fibers: Impact on Fiber Properties

Flax fibers, available as fiber bundles, are commonly used as fiber reinforcement in composite materials as a substitute for glass fibers. Pre-treatments are often necessary for improving fiber-resin adhesion, and also to facilitate fiber elementarization, and to improve fiber ability to be implemented in mechanical processes limiting fiber damages. This paper focuses on the impact of biotechnologies (effect of 2 different enzymes: a pectate lyase and a laccase) and of an ecotechnology (ultrasound with ethanol), compared to classical chemical pre-treatments (using aqueous NaOH and ammonia) on the final flax fiber bundle properties, before and after a carding process. Fiber surface properties (wettability and/or zeta potential values), fiber elementarization and mechanical properties vary with the type of treatment (chemical nature of product and conditions used). Fibers elementarised using pectate lyase and ultrasound/ethanol have a hydrophilic surface and a high water absorption capacity, and are also of highest quality in terms of increased fineness. Treatment with NaOH yields the poorest fiber bundle tenacity. Laccase enzyme yields long thick hydrophobic fibers having very low water absorption capacity, and the most neutral surface charge. Properties of flax fibers can be easily monitored using different pre-treatments resulting in fibers which would be suited for various final applications.