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Proses dehidrasi merupakan salah satu proses yang sering dijumpai pada pabrik pengolahan gas alam. TEG (triethylene glycol) merupakan senyawa Glycol yang biasa digunakan pada proses dehidrasi gas alam. TEG dimanfaatkan sebagai absorben pada absorpsi air yang masih terkandung dalam gas alam yang bisa menyebabkan hydrate dan korosi. Proses absorpsi ini dilakukan di TEG contactor, TEG yang sudah digunakan akan dilakukan regenerasi, jika sudah di regenerasi maka TEG akan digunakan kembali. Tujuan dari penelitian ini yaitu melakukan proses estimasi temperatur yang sesuai untuk proses absorpsi unit regenerasi TEG, karena banyak TEG loss pada proses ini. TEG loss terjadi di TEG regenerator dan biasanya disebabkan oleh temperatur kondensor refluks yang kurang tepat sehingga menyebabkan TEG teruapkan keluar ke atmosfer bersama uap air. Kehilangan TEG adalah masalah bagi operasi yang penting dalam sistem dehidrasi. Langkah yang digunakan untuk mengurangi TEG loss adalah dengan melakukan estimasi temperatur dari condensor refluks dibuat menjadi 100°C dengan cara mengubah temperatur reboiler dari 190°C menjadi 197,3°C.

The life span of a structure depends on the strength and durability of concrete. The use of mineral admixtures in concrete plays a major role in achieving higher strength and durability characteristics. At present nanotechnology is being used in the concrete to decrease the permeability of concrete and also to extend the life service. Nanomaterials are extremely small in size which when used in concrete, improves the strength and reduces porosity. This study gives the characteristics of concrete when Nanosilica (NS) and Multi-Walled Carbon Nanotubes (CNT) were added to it. Manufactured sand was used as a fine aggregate in replacement of natural river sand. For conventional and nano-concrete, the durability characteristics were assessed by conducting water absorption, sorptivity, accelerated corrosion, and carbonation tests after 28 days and 90 days of curing. The formation of hydration products was studied through microstructural analysis by SEM and XRD. Closely packed concrete was achieved with the addition of NS and CNT. The permeability and porosity were reduced for nano-concrete because of the filler effect of nanomaterials.

Plastics are an increasingly important component of urban solid waste. The disposal of waste materials, such as used plastic bags, has become a major issue. The vast amount of waste plastic bags collected in the twenty-first century has posed significant challenges for their disposal. The amount of waste plastic in the home is substantial and growing. Our results indicate cement blocks are ideal for laying and finishing pathways and streets because they are easy to lay and finish. This study was carried out on experimenting the substitute materials in the mixture of cement blocks a component of building materials which is normally manufactured using the mixture of cement, fine aggregate and water, following a certain ratio. A series of three different percentages of plastics bags were added with the mix and certain quantities were replaced by quarry dust instead of Fine aggregate. Tests were done on the blocks to study its compressive strength, split tensile strength the water absorption percentage and acid test. Both the test compressive and split tensile tests were conducted on the seventh and 28th day. Based on the results acquired, for compressive strength tests on the 28th day, the result a good indication is that the blocks can be produced by replacing the cement and fine aggregate with utilizing the plastic for and effective way of 1:1 and 1:2, with 10& 20% replacing with quarry dust having strength 10.7 and 9.5 N/mm2 respectively Which is 165 more than the conventional type of blocks. Similarly the water percentage is also nil and very marginal in the same proportions. The decrease in weight is existed in all the samples tested the result is equal in all mix compositions. This is uniform rate implies block undergo certain abrasion. Conclusions were drawn for utilising the above composition in a suitable non structured places and minimizing the plastic waste.

Carbon Nano Tubes are strongest known materials known till now which can be ideally used in conventional concrete to tailor its functionalities. As water cement ratio governs the strength, serviceability and durability of concrete so its important to know the effect of Carbon Nano Tubes on basic properties of concrete. In order to analyze fresh and hardened properties of conventional concrete 0.5% Carbon Nano Tubes by weight of cement was incorporated in concrete mixes having water cement ratio 0.40, 0.45, 0.48.0.50 and 0.50. It was observed at 0.45 water cement ratio compressive, split tensile and Moment of resistance was greater by 8.89%, 28.9% and 5.33% respectively in comparison to Reference mixes while workability diminued by 38.40% and water absorption decreased by 0.03%. Also Coefficient of relationship R2 for water absorption and water-cement ratio of Carbon Nano Tube reinforced concrete was found as high as 0.97. Scanning electron microscopic analysis revealed dispersion of Carbon Nano Tubes and their bridging effect.

The housing problem in Tunisia has become more acute due to the high cost of construction materials, thus constituting a source of concern for the population. To resolve the crisis, upgrading abundant local materials has become a necessity. This paper aimed to assess the potential use of Jebel Menchar's geomaterial to develop compressed earth brick (CEB). Laboratory tests were performed to determine the physical, chemical and mineralogical properties. Series of destructive and non-destructive tests were carried out to characterize the properties of bricks based on their composition in terms of compressive strength, flexural strength, water absorption and ultrasonic testing. The results indicated that all of the bricks studied exhibited a compressive strength greater than 2.3 Mpa during the 28-day experiments, thus suggesting a high potential ability to reduce building material problems, while also providing the brick industry a useful and inexpensive new raw material with less CO2 emissions.

A swelling pressure cell is introduced to measure apparent swelling pressure (ps) and basal spacing of montmorillonite (d001) simultaneously for compacted bentonite during water absorption. Specimens with an initial dry density of up to 1·7 Mg/m3 were prepared with initially oven-dried bentonite powder. Results show that the ps time history curve has four stages: a sharp increase to the peak swelling pressure (pp); a drop to a valley swelling pressure (pv); another increase to the initial swelling pressure for equilibrium (pei); and equilibrium swelling pressure (peq). Meanwhile, d001 changes from 0·98 nm to 1·26 nm, 1·58 nm, 1·90 nm and 4·0 nm gradually during water absorption. Results imply that crystalline swelling of montmorillonite serves an important role for interpretation of ps behaviour of tested specimens. Another testing programme to measure ps compacted bentonite only was conducted using the swelling pressure cell. Results suggest that specimen dry density closely correlates with feature points of ps time history (i.e. pp, pv, pei and peq), which is consistent with results of earlier studies. Importantly, the 2 mm specimen thickness was used, which reduced the test duration to less than 24 h. Evidence from experiments suggests that the swelling pressure cell is a powerful and inexpensive tool for studying the swelling behaviour of compacted bentonite.

Oil palm shell (OPS), one of the most abundantly produced solid bio-wastes in Southeast Asia, is yielded by crushing the oil palm kernel during palm oil extraction in the palm oil mills. Approaches have been devoted to developing the use of OPS as reinforcing filler in polymer composites to enhance the functional properties of composites. For OPS to be effective for reinforcing materials, its role and beneficial effects on the improvement of composites’ properties need to be investigated. However, not many studies have discussed the potentials of incorporating OPS in thermoplastic and thermoset polymer composite applications. This paper summarises the enhancement of composite characteristics, including physical, mechanical, thermal, water barrier and biodegradability properties. Properties of OPS that make it a good candidate as a reinforcing filler, such as tensile strength, impact strength, elongation, Young’s modulus, morphological and water absorption, are discussed in detail. In addition, the application of its derivative, challenges, and outlook are also discussed.

In this study, we evaluated the characteristics of five commercial resin composites used for provisional restorations. The inorganic filler contents of the resins were measured, and three-point bending, wear, surface hardness, water absorption, and staining tests were performed. The specimens underwent additional three-point bending tests after water storage and undergoing thermal stresses at 5°C and 55°C (10,000 cycles). Data were analyzed using one- or two-way analysis of variance and Bonferroni post-hoc tests. Pearson's correlation coefficient was used for pairwise comparisons. Each resin composite presented with different mechanical properties, based on variations in the inorganic filler content. The flexural strength of each resin composite was significantly decreased after water storage. There has a positive correlation between flexural strength and dynamic hardness but a negative correlation between flexural strength and maximum wear depth. The types and contents of the inorganic fillers, the composition of the monomer in the resin matrix, and the addition of plasticizers can affect the properties of the material.

This paper discusses the effects of the silicon dioxide to aluminium oxide molar ratio, sodium oxide to aluminium oxide molar ratio and concentration of sodium hydroxide on the water absorption and compressive strength of synthesised fly ash-based geopolymers. Geopolymer pastes were prepared using fly ash mixed with an alkaline activator consisting of sodium hydroxide solution and sodium silicate solution. The phase composition, microstructure and chemical bonding of the synthesised products were characterised after 7 and 28 days using X-ray diffraction, scanning electron microscopy and Fourier-transform infrared spectroscopy, respectively. The synthesised geopolymer with a silicon dioxide to aluminium oxide molar ratio of 5 and a sodium oxide to aluminium oxide molar ratio of 1.2, activated with 10 M sodium hydroxide, was found to have the highest strength and the lowest water absorption. The compressive strength was observed to increase with increasing silicon dioxide to aluminium oxide molar ratio. A high initial molar ratio of sodium oxide to aluminium oxide enhances the water absorption and decreases the strength of the geopolymer sample. The dissolution of silica and alumina from the starting materials becomes more efficient as the concentration of sodium hydroxide increases.

The construction industry is always in need of new technologies and products that improve technological characteristics. Alkali-activated materials appear as an alternative to reduce energy costs, improve technological properties and still present themselves as materials with the potential for incorporating industrial waste. The objective of this research was the development of roof tiles through the process of alkaline activation using ash from the kilns of burning of a red ceramic industry. After the process of processing the materials and their characterizations, prismatic specimens (115 × 30 × 20 mm) were made with the replacement of 0, 6.25, 12.5, 25 and 50% ash by metakaolin and subsequently separated into two groups, (i) subjected to curing at room temperature and (ii) subjected to curing at a temperature of 80 °C, in both cases with a curing time of 7, 14 and 28 days. After each curing period and group, the specimens were subjected to technological evaluation of water absorption, porosity, flexural strength and scanning electron microscopy. The results obtained demonstrate that the use of ash from ceramic waste, mainly replacing 12.5% of the metakaolin, promotes a reduction in water absorption and porosity, and an increase in flexural strength. The results obtained at 28 days in thermal curing are 44.05 MPa for 12.5% ash, much higher than the reference composition (16.02 MPa). The increase in strength happens due to the formation of tobermorite, due to the calcium present in the ash, and due to the formation of phases rich in potassium from the ash, such as kalsilite. Thus, it is concluded that the use of ash from ceramic waste is possible in the alkaline activation of roof tiles due to the occurrence of additional mechanisms of alkaline activation.

Mullite is one of the preferred aluminosilicates for both traditional and advanced ceramics. This paper reports the use of simplex-centroid mixture design to prepare mullite–glass ceramics by reactive sintering. The phase composition and technological properties of formulations containing kaolinitic clay, kaolin waste and alumina were investigated after sintering at 1400 °C. The sintering behavior was assessed by dilatometry. Microstructural analysis indicated the crystalline phases mullite, residual quartz, cristobalite, and α-alumina. A glassy phase was also identified as a matrix embedding mullite grains (as seen by X-ray diffractometry and scanning electron microscopy). In kaolin waste-rich formulations, a liquid phase sintering mechanism favored the densification process and the mechanical resistance. Highly significant statistical models allow correlating the concentrations of raw materials with linear firing shrinkage, water absorption and apparent porosity. Overall results stand out for the potential of using kaolin waste in the preparation of mullite–glass ceramics.

This study focused on the optimization of the production conditions of an ultrahigh expanded perlite lightweight aggregate-filled fly ash-based geopolymer composite and the determination of its product properties. The geopolymer matrix was synthetized using mechanically activated fly ash and an alkaline solution. In a systematic series of experiments, the effect of expanded perlite (EP) content, the compaction pressure and the compaction time on the mechanical properties of the lightweight composite were investigated. In the case of the optimal production conditions, the composites were characterized in terms of physico-mechanical properties, water absorption and microstructure. The composites produced under optimal conditions had an average uniaxial compressive strength of 246 kPa and density of 534 kg/m3 at 80% by volume EP content, and 264 kPa and 221 kg/m3 at 95% by volume EP content. Both the FT-IR spectroscopy and scanning electron microscopy results proved the formation of main geopolymerization reaction products in the matrix of the composite, as well its reaction with the lightweight aggregate.

The hydrogel sponges have prepared successfully from gelatin/chitosan (GEL/CTS) matrix with different polyols basing on scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) analysis. The results indicate that the compressibility and thermal properties (thermal gravimetric analysis, TGA) were improved significantly with adding the different polyols [poly(vinyl alcohol) – PVA, and poly(ethylene glycol)-poly(propylene glycol)- poly(ethylene glycol) – PEPEG] into GEL/CTS matrix. Specially, the as-prepared hydrogel sponges with superabsorbent behavior were also investigated with the attained water absorption capacity to 605 ​g ​g−1 and 585 ​g ​g−1 for GCV_1/1/0.3 and GCE_1/1/0.3 sponges, respectively, as well as the excellent water absorption capacity in a wide range of pH and salt concentration. Hence, these studies demonstrated that the hydrogel sponges are concerned as potential and promising candidates to apply especially in the fields of biomedicine and hygiene.

Concrete is one of the largest consumer products all over the world. Concrete consumes large quantity of natural ingredients like river sand in the form of fine aggregate and crushed stone or gravel in the form of coarse aggregate. With due consideration for sustainable construction, the concrete can be minimized by utilizing the waste products from various industries as an alternative for components in concrete. This paper deals with reuse of industrial waste foundry sand and agricultural waste coconut shell in biased form for fine aggregate and coarse aggregate [Siddique, R and Kadri, EH (2011)]. From the mechanical properties of concrete containing both the waste products, the optimum replacement levels were arrived at 25 % and 15% for waste foundry sand and coconut shell. The durability properties such as water absorption, porosity, sorptivity and water permeability are found for improvised concrete and compared with normal concrete.

According to the latest studies, nanoparticles are the best additive materials to improve concrete's mechanical properties. Among these nanoparticles, Carbon Nanotubes (CNTs) are famous for their extreme tensile strength and flexibility. These particles can be used as a reinforcement to increase the mechanical properties of concrete. In the present study, the effects of using CNTs with different dosages were investigated on structural lightweight concrete’s mechanical properties. Structural Lightweight Expanded Clay Aggregates (LECA) were used in the mixture of Structural Lightweight Concrete (LWC) as a substitute for coarse aggregates. Along with LECA, CNTs as a partial replacement for cement with varied weight ratios were added to the lightweight concrete (0.02, 0.1, and 0.3 percent of cement weight). The effects of carbon nanotubes on fresh concrete performance, water absorption, compressive strength, tensile strength, and flexural strength of 7- and 28-day lightweight concrete were carried out. The results indicate that the presence of 0.02% of cement weight of CNTs increased compressive strength, tensile strength, and flexural strength of the 28-day-old lightweight concrete up to 29%, 44%, and 26%, respectively. Moreover, it reduced the water absorption of lightweight concrete by 28.3%. Utilizing more content of CNTs resulted in less mechanical properties. Having done experimental tests, nanoparticles and cementitious materials bonding have been visualized by Scanning Electron Microscopy (SEM) device.

Microbial self-healing is an innovative technology which repairs cracks in concrete by precipitation of calcite. The main focus of our research study was focused on evaluating the performance of synthesized microbial agent with Bacillus sphaericus (spore forming urelotic strain) of cell dosage 105 cells/ml in repairing cracks in fly ash concrete. The bio-based agent is added to cracks in fly ash concrete. The effectiveness of prepared bio- based agent in repairing the cracks in concrete was assessed by comparing with non-based agent prepared with cement, sand and water. The mechanical and water absorption property are evaluated. The compressive strength and water absorption of micro-repaired concrete was found to increase by 10% and 6 % in comparison with non micro repair concrete. Scanning electron microscope analysis of concrete samples was done to confirm formation of calcite. The analysis showed formation of calcite particle near the microbial cells. This confirms that the improvement in properties of concrete is due to formation of calcite particles due to biomineralization process. Use of Micro-based agent would lead to environmental and economical benefit. Over all the maintenance and repair cost could be reduced and also play a role in reducing green house gas emissions and help to develop sustainable concrete.

A novel ceramic composite has been obtained by introducing polyvinyl alcohol in magnesium-based chemically-bonded ceramics and exploiting the cross-link reaction with glutaraldehyde during setting. The properties of the obtained material and the interaction of the polymer with the cement reaction have been investigated. Several beneficial effects were observed. Namely, an extension of the working time, a reduction in the water sensitivity, a decrease in the rate of the heat evolution during hardening. The latter has been ascribed to the intervention of surface adsorption processes, which hindered the dissolution of MgO, as well as the nucleation and growth of the magnesium phosphate products, in concert with the film forming ability of the polymer. Thanks to the complementarity of their mechanical properties, the cement and the additive operated in a synergistic fashion, allowing for the obtainment of a material possessing higher strength and better elastic properties. Three-dimensional quantitative image analysis from synchrotron X-ray microcomputed tomography evidenced the development of a more compact microstructure, comprising a higher number of crystals of smaller size. As a consequence, the pore network exhibited a higher fraction of small pores and lower pore connectivity. These characteristics contributed to hinder the water absorption, as confirmed by the fluid transport simulations within the volume. The observed correlation between the solution pH and the polymer cross-link density offers the way to effectively modulate the material performance by acting on the chemical environment thanks to its compatibility with the cross-link reaction.

The present study deals with the utilization of Groundnut Shell Ash (GSA) as a partial replacement for fly ash in making unburnt fly ash bricks. The percentage of GSA was varied from 10% to 33% in the manufacturing of bricks. Various tests such as specific gravity, bulk density, SEM, EDX, compressive strength, water absorption and efflorescence tests were conducted to analyse the effect of GSA in fly ash bricks. GSA when used in the making of unburnt bricks gives a satisfactory result in terms of its compressive strength. The strength obtained under optimum combination was found to be nearly equal to the prescribed value for first-class bricks. Water absorption was found to be 12.17% and efflorescence was found to be 8% which is well within the prescribed limit as per Bureau of Indian Standard. From the test results it is concluded that, the maximum optimized compressive strength is obtained for a combination of 25% GSA, 10% Fly Ash, 25%lime, 3%Gypsum and 37%Quarry dust. The GSA brick will be a commercially viable building material and also cheaper as it is abundantly available. Hence, a sincere attempt was made to find innovative, durable and economic alternative construction material in the form of brick by utilising the Groundnut Shell Ash.

Nowadays concrete and mortar demand as construction materials has been surged in market due to the exorbitant augmentation of the construction industry. Cement and fine aggregates (like river sand, pit sand etc.) are consumed in a large quantity to produce the mortar for various uses. In this venture, the cement and natural sand is been replaced with the soda-lime glass and the properties of mortar has been characterized for this replacement. Various proportions adopted for the cement replacement by weight 0–20% and natural sand replacement by weight are used 0–30% at 5% interval. The influence on the workability, density, water absorption, mechanical strength, drying shrinkage and Alkali Silica Reaction (ASR) expansion are assessed. Outcome of the investigation reveals that the dose of soda-lime glass replaced with cement and natural sand plays an important role to determine characteristics of cement mortar. Mortar made with Glass powder (GP) at 15% replacement with cement and Glass sand (GS) at 25% replacement with natural sand have highest mechanical strength. Water absorption and density reduced by using soda-lime glass. Drying shrinkage mitigate by using waste glass. ASR expansion has reduces due to smaller particle size of glass. The pores refinement and porosity decrement occurs due to the calcium hydroxide (Ca(OH)2) and glass powder reaction, this is a pozzolanic reaction that produces calcium silicate hydrate (C-S-H) gel.

Because of their high strength-to-weight ratio, composites outperform traditional materials. Natural fibers are increasingly being used in composites due to environmental concerns. Their hygroscopic character, on the other hand, has a negative impact on the mechanical properties of the composites. The need to analyses the water uptake characteristics of natural fiber hybrid composites has arisen as a result of composites' use in decking, flooring, and outdoor facilities. The objective of this paper is to study the water absorption behavior and observed that banana/glass fiber composite keeps on increasing. The conclusion is that banana fiber absorbs more water than kenaf/glass fiber composites, and there are numerous causes for trapping of natural fiber water consumption.

Mostly, agricultural residues and fibers are incinerated or dumped into the land after cultivation. Disposal of these waste not only occupy more useful space in land but also spoiled energy resources. It causes pollution to the environment, release of greenhouse gases, etc. Lignocellulosic fibers are rich in cellulose which is abundant in nature. In this work, Banana fiber which was extracted from the bast of the plant is used to make an alternate for synthetic fibers. The polyester based composites were manufactured by with different weight concentration of fibers from 1 to 10%. Tensile and water absorption values of composites were conducted as per the ASTM standards. When the fiber addition increases, water absorption properties also increased due to the characteristics of lignocellulose fibers. From the results, it was understood that the obtained composites can be used in various commercial and bio medical application.

Environmental benefits and amazing performance can be obtained by utilizing palm oil fibres and kenaf fibres which illustrate colossal potential in fibre reinforced composites. An investigation has been made to determine the effects of alkaline treatment on water absorption and swelling behaviour of palm oil fibre composites as well as kenaf fibre composites. Untreated and treated natural fibres and were prepared in random orientation with different volume fraction of palm oil fibres and kenaf fibres; 30%, 40%, and 60. All the treated fibres were treated with 1 w/v% and 5 w/v% of sodium hydroxide concentration. Water absorption test was performed by immersing the sample in the distilled water periodically measuring the sample weight. Thickness swelling test was carried out by measuring the thickness of the specimens before and after soaking in the distilled water within certain period of time. All specimens were observed under Scanning Electron Microscope (SEM) to study the fibre morphology. TPOF_30_5SH achieved the least percentage of water absorption (1.44%) when it was compared with the UPOF_30 and TPOF_40_1SH. UPOF_60 shows the highest percentage of thickness swelling (8.96%). TPOF_30_5SH and TPOF_40_5SH show reduction of water absorption when they were compared with UPOF_30 and UPOF_40 respectively. All the treated kenaf fibre composites with 5 w/v% sodium hydroxide concentration such as TKF_30_5SH, TKF_40_5SH and TKF_60_5SH show improved result of thickness swelling. Materials covering the surface of palm oil fibres and kenaf fibres were more effectively removed with 5 w/v% sodium hydroxide than by treatment with 1 w/v% sodium hydroxide while observing under SEM.

Soil Reinforced Blocks are the new attempt in which a soil block of definite size and shape is produced by incorporating the Reinforcement into the Stabilized Soil by wrapping the Geomembrane around the soil block with the proposal of applying it as a Foundation Bed. Red soil is primarily stabilized by using Portland Cement and Steel bars are used as Reinforcement, by using these materials Soil reinforced blocks are constructed which is similar to the construction of Reinforced Concrete Columns in the form of solid blocks. The main objective of the work is to produce an Engineered Efficient Structure in the form of soil reinforced blocks to provide a Solid High Resistance Foundation Platform to the structure by placing these Soil Reinforced blocks in the ground where Foundation Soil has Low Bearing Capacity. After the construction of Soil Reinforced blocks, these are tested against Compression, Bending Tension, Triaxial Shear, UCS, CBR, and Water Absorption. To avoid the Saturation or Entry of Water into the Soil Reinforced blocks a Geo-Synthetic material named Geo-membrane is used. A Geo-membrane is a Synthetic material with the primary function of Obstructing Moisture and it will be wrapped around the Soil Reinforced blocks. A Geotechnical Structure possessing the Good Engineering properties are the Expected Possible Outcomes.

In the age of sustainability, it is necessary to prevent the depletion of natural resources to maintain needs and ecology. Hence, in the process of manufacturing mud and fly ash bio-bricks, materials like fly ash and bacterial solutions (Bacillus Megaterium and Bacillus Subtilis) are widely used. The experiment was carried out at various pH levels (basic, acidic, neutral) and at different temperatures (4, 31, 60 °C) with two different kinds of water (lab grade, groundwater) to find the optimum mix proportion of a brick. Bricks were cast by the MICP method where bio-mineralization (a process that converts CaCl2, urea, and bacteria into CaCO3) takes place. An experimental program has been carried out at various ages of bricks in order to determine the physical and mechanical properties of bricks, such as compressive strength, water absorption, hardness, size, shape, and color. The experiment results are used to determine the effect of bacterial solutions and fly ash content on the unburnt brick’s properties. The bricks tested showed comparatively better properties than the conventional and hence they are good to be used in temporary construction.

This paper investigated the effect of rice husk ash (RHA) on chloride permeability, water absorption, and permeable pore space of cementitious mortar. It was observed that the permeability, water absorption, and permeable pore spaces of mortar mixtures having rice husk ash as partial replacement of cement decreased as the amount of rice husk ash increased while the compressive strength increased. The reduction in chloride permeability, water absorption, and permeable pore space ranged between ∼3 to ∼52, ∼2 to 10%, and ∼2% to 18% with 4% to 12% RHA dosages without RHA mixture. In addition, linear co-relation exists between water absorption and permeable pore space and permeable pore space and charge pass with a coefficient of correlation of 0.93 and 0.90, respectively; quadratic polynomial co-relation exists between compressive strength and water absorption and compressive strength and permeable pore space.

Steel filings are primarily composed of steel. These steel filings are produced by grinding, shaving and cutting the various steel in the mechanical workshop or factories. The steel wastes are disposed into the landfills, rivers and oceans thereby increasing pollution. To reduce these wastes reaching the landfill sites, one solution is to reuse them in construction. There have been some studies on the strength of concrete made with steel filings, however, no study has been reported on the durability. The purpose of this research was to evaluate the durability of concrete made with steel fillings as a replacement of fine aggregate. In the current study, different replacement levels of steel fillings such as 0%, 10%, 20%, 30% and 40% have been used in the making of concrete. Cube samples were tested for durability after normal curing for 28 days. It was found that the cube looses its workability and slump, when the percentage of steel filing were increased beyond 40% as replacement of fine aggregate. The water absorption increased with increasing percentage of steel filing and the sorptivity tests showed that the weight of capillary rise of water increased with the increasing percentage of steel filing due to the increased porosity of the concrete. This type of concrete may be used for the pavement and parking lots, where there is a problem of water logging, as it would allow the water to pass through it and may help in recharge of the ground water.

The current study mainly aims on the usage of waste coarse slag aggregates (CSA) to prepare coarse slag aggregate concrete (CSAC). The waste slag aggregates are the by-products mainly obtained from the iron and steel industries. These wastes are mostly disposed off into the landfills and the newer alternative method of disposing are being researched. Also, the increasing rate of construction has resulted into the diminishing of natural raw materials. The present paper focuses on incorporating CSA as the replacement of 20 mm natural coarse aggregates to prepare CSAC for various volumetric replacement of 20%, 40%, 60%, 80% and 100%. Cube and beam samples having different percentages of CSA were casted to undergo the experimental analysis. The fresh, mechanical and durability parameters has been studied by performing workability, density, compressive strength, split tensile strength, ultrasonic pulse velocity, water absorption and water permeability tests, for the in-depth analysis. The outcomes from the experiments has shown decrease in the strength and durability properties for increasing count of CSA. Decrease in compressive and split tensile strength of 39.08% and 37.50% respectively was observed for 100% CSA replacement. In case of durability properties, the penetration depth has increased up to 69.84% for the 100% CA replacement sample. However, a very marginal decrease in the values were observed for the replacement content up to 40%. The study concluded that the utilization of slag aggregate is a sustainable approach by preserving the naturally available raw materials and also construction can be made economical.

In this work, the hybrid natural fiber composites (NFCs) were prepared using a standard hand lay-up technique from Banana fiber (B), Sisal fiber (S), and sawdust (SD) with different compositions viz. S-I (B 60%–S 20%–SD 20%), S-II (B 80%–S 5%–SD 15%) and, S-III (B 80%–S 15%–SD 5%) bounded with 80% epoxy resin LY556 and hardener LY953 in the 4:1 ratio as per ASTM standards. All the specimens were made with proper composition of 20 wt% of reinforcing materials and 80 wt% of the matrix material. The mechanical (tensile strength, compressive strength, flexural strength, and impact strength) properties and Brinell hardness of prepared specimens were conducted according to ASTM standards. The tensile, compressive, flexural, and impact strength, as well as Brinell hardness of the prepared NFCs, were found to increase with the increase in sawdust content in the epoxy matrix. Further, an improvement in the water absorption property was registered with the increment of sawdust content in the banana-sisal/epoxy composite. The value of dielectric permittivity increased while that of tangent loss decreased with increasing sawdust content. The improved mechanical, dielectric as well as water absorption properties and better Brinell hardness, foreshadow the industrial promises of the present NFCs a better alternative for synthetic fiber-reinforced composite materials.

The effects of adding iron oxide to ceramic glaze formulations were studied in this study. Iron oxide was added in different weight ratios into the reactive transparent glaze, reactive opaque glaze, and transparent glaze formulations. The iron oxide content in the glaze composition, the coloring mechanisms, the phase distributions, and surface properties at temperatures of 950–1000-1050-1200 °C in the oxidation firing medium were investigated. Scanning Electron Microscopy (SEM) to determine the microstructural and morphological characterizations of the test glazes, X-Ray Diffractometry (XRD) to determine the crystallographic properties and phases, and X-Ray Fluorescence (XRF) analyses to determine the elemental and chemical composition were performed. In addition to these, surface images were examined with Digital Microscope (DM) and Commission Internationale de l'Eclairage (CIE) L*a*b, and water absorption values were compared. In addition, taking into account environmental factors, a comparison of ceramic glazes with the same amount of waste iron oxide was also performed for same purpose. As a result of the studies, it was observed that the addition of iron oxide and/or waste iron oxide did not have a negative effect, and coloring effects on the glaze layer were observed at different rates and firing temperatures.

The main components of concrete are cement and river sand (R-sand). Due to excessive production of cement, CO2 emission also increases which causes air pollution. On using R-Sand, large scale depletion of natural sources creates environmental problems. In view of the increasing national and global consensus on the environmental protection, the governments have put restrictions on mining of R-Sand from the river beds. To overcome these problems, there is a need of cost effective alternatives materials so as to make the construction sustainable without compromising its quality. In the production of Self Compacting Concrete (SCC), fly ash (FA) is utilized as an additional cementitious ingredient, which improves its performance. It solves the problem of FA disposal and environmental pollution too. The manufactured sand (M-sand) is also an alternative material which may solve the problem of shortage of R-Sand, if found suitable. In this study, M-Sand and FA were incorporated in the preparation of a sustainable SCC. After optimisation of FA and M-sand doses in the final mix, two types of SCC mixtures were developed: M-1, which consisted of 100% OPC + 100% R-Sand, and M-2, which consisted of 80% OPC + 20% FA + 50% R-Sand + 50% M-sand. Fresh properties of all SCCs were determined as per EFNARC/BIS recommendations. For destructive testing standard size specimens were cast to determine desired strengths after curing in tap water for 90 days. Rebound Hammer (RH) and Ultrasonic Pulse Velocity (UPV) were utilised in Non-Destructive Testing (NDT) to determine the strength, homogeneity, and integrity of both SCCs. Further, the water absorption of the specimen was measured up to 90 days. XRD analysis was also performed.

This study focus on the physical characterization of short roselle fibre polymer composites. Short roselle fibre composites with 10%, 20%, 30% and 40% fibre content by weight were produced using the hand lay-up technique. Composite’s physical properties like density, void content and water uptake capacity were obtained as per ASTM standards. The void content of the composites ranges from 1.28 to 6.71%, which is quite low for short and randomly oriented composites. The saturation in water uptake was observed after 7 to 8 days of water immersion. The water uptake capacity of the roselle fibre composites increases with an increase in fibre content. It indicates the composites with the lower fibre content yield a higher resistance to water absorption.

Waste is a common ingredient in Malaysia that has to do with man-made waste. Waste materials can be abundant in landfills without any profit. Waste materials can be harmful to the environment as well as to human health. One of the most abundant wastes is coal combustion ash from coal-fired power plants. In addition, the most common material used in the construction industry is brick. Bricks have been used for non-polluting structures and must be made of durable materials. The common material used for bricks is clay, sand and cement. All these ingredients are derived from natural resources. The depletion of natural resources has been a cause of concern for many. Therefore, this paper focuses on the development of bricks from coal terms of mechanical properties. The density, compressive strength and water absorption capacity of bricks made from coal ash were investigated after curing for 7, 14 and 28 days. The results show that the density of bricks made from coal ash is low, while the compressive strength meets the requirements and is 10.25 MPa and 8.67 MPa higher than control concrete, respectively. For the crushing value, the coal ash was compared with the coarse aggregate to meet the requirements of the test. The result shows that the coal is 34.6% higher than the natural aggregate. In conclusion, the use of coal ash in the production of bricks is a promising long-term option for the production of bricks.

Plastic waste is accumulated in recent years, causing environmental problems, particularly in developing nations. Recycling this waste as building materials is considered as a feasible solution to the environmental issue, but it is also a feasible solution to the issue of building economic design. This research aims to study the possibility of using plastic waste in the manufacture of unconventional bricks that are light in weight, environmentally friendly, inexpensive, and as an alternative to traditional bricks made from fossilized clays for use in the construction industries. In this paper, we use the remnants of medical syringes made of low-density polyethylene and two types of additives were added sawdust and sand in different proportions. The melting and moulding process was used in manufacturing. Testing has been conducted to identify hardness, density, water absorption, compressive strength and also to determine morphology properties by FTIR and SEM. The results showed that bricks made of plastic and sawdust gave a high compressive strength of 66Ϻpa at 20% of sawdust higher than bricks made of plastic and sand with a value of 61Ϻpa at 60% of sand. In both cases, they gave a higher compressive strength than ordinary bricks, as well as a very low absorption rate. The density was very low, especially with sawdust, where the highest value was 0.8985 g/cm3of pure polymer, and for sand, it was 1.4321 g/cm3 at 60% of sand and it gave good hardness values. The FTIR results showed that there is no chemical reaction, but only a physical reaction between the polymer and the additives, and through SEM, it was observed that there is homogeneity between the polymer and the additives. As a result, the study presents a new line of investigation into the sustainable recycling of the circular economy of waste thermoplastics.

As the population around the world is on the rise so to meet consumer's needs a large amount of solid waste is generating and it needs large landfill sites for disposal of this waste. Alteration of this solid waste into other alternative resources will reduce the load on non-renewable resource materials and this can help in solving the landfills problem. Numerous studies have drawn attention to the usage of solid waste in concrete production, which is an imperative material for construction. Specifically, those that can replace fine aggregate because these days many states have banned the use of river sand so researchers all over the globe looking for a suitable material that can replace river sand and also provide sustainability with better strength results. In this study, bone china cup plate-type ceramic waste powder was utilized as a fine aggregate. Ceramic waste powder (CWP) creates environmental degradation and the use of CWP in concrete as a substitute for natural resources would have a positive result on the environment. In this study, the sand was replaced partially with CWP at replacement levels of 0%, 10%, 20%, 30%, 40%, and 50% by the weighted amount of sand. To evaluate various properties of SCC mixes with CWP, various workability tests (i.e. slump flow, v-funnel, j-ring, and l-box) were performed in a fresh state of concrete, while compressive strength, ultrasonic pulse velocity, flexural strength, and water absorption tests were computed to measure the hardened characteristics of SCC mixes. In SCC mixes, the CWP confederation showed an improvement in mechanical strength of concrete at the 20% CWP placement stages and a decline above 20% CWP replacements in all strength characteristics.

Natural fibres now a days replacing the conventional structural materials such as Aluminium, steel, wood etc. with their excellent weight to strength ratio and with their high mechanical properties. In this present investigation hybrid composites were fabricated using Hand layup process using the natural fibres such as Banana, Coconut, Jute and Cotton fibres reinforced with Polyethylene at different weight proportions of 5, 8, 10, 12, 15, 18, 20 wt%. Tests such as water absorption, flexural rigidity, tensile, hardness and few other mechanical tests were conducted on the hybrid natural fibre reinforced composites. Among the hybrid composites the coconut fibre with 20 wt% and banana fibre with 18% shows high tensile strength with 56.4 N/mm2 and 54 N/mm2 and flexural strength. Water absorption is less in the hybrid composite with coconut and cotton fibres as reinforcements and gains mass of 5gm and 7gm.

Nowadays, the accumulation of various waste products is increasing day by day. So there is a great need for their proper disposal, without harming the environment. Moreover, due to the limited availability of natural resources like fine aggregates. There is a need for alternative building materials. The study's primary goal was to find an alternative, effective disposal method of dry sewage sludge of wastewater treatment plants as a building material. The possibility of using dry sewage sludge in concrete was assessed in this study. Various properties, like workability, compressive strength, ultrasonic pulse velocity, split tensile strength, water absorption, and cost-benefit analysis were reported in the study. According to the study, utilizing 5% of dry sewage sludge as a fine aggregate is possible without having a significant negative influence on concrete characteristics. With the use of dry sewage sludge, the manufacturing cost of concrete can be reduced by 1.63%.

Ultraviolet (UV) radiation is one of the most common methods for sterilizing materials with suspected biological warfare agent contamination. In this study, UV laser sterilization of ceramic tiles was investigated as a method for destroying Bacillus atrophaeus spores. The effects of UV irradiation were evaluated as a function of water absorption (porous and vitrified), tile color (black and white), and surface brightness (matte and glossy). Spores were loaded onto the surface of each tile and irradiated with a 266-nm UV laser. The irradiated spores were then removed by scraping with a razor blade and cultured in an agar plate for 24 h. The sterilizing effects of the UV laser were greater on the vitrified (group BIb) tiles than on the porous (group BIII) tiles. In addition, sterilization was more effective on white and matte tiles than on black and glossy tiles, respectively.

In order to avoid the energy consumption of dewatering and dust pollution in the preparation of non-sintered lightweight aggregates from dredged sediment, a new low-dust process of preparing non-sintered extruded wrap-shell aggregates (TH-WSLAs-W) by extrusion granulation is proposed and applied to produce TH-WSLAs-W baking-free bricks (TH-WSLAB-W). The basic physical properties (cylinder compressive strength, bulk density and water absorption) and microstructure of TH-WSLAs-W was explored. It shows that the curing agent will form a hydrophobic gel film around the sediment particles and form a network structure, which enhances the cylinder compressive strength (6.7 MPa) and frost resistance of TH-WSLAs-W. In addition, the interfacial transition zone among TH-WSLAB-Ws was studied by scanning electron microscope. It found that the micropore structure endow the TH-WSLAs-W with excellent water absorption and drainage property, promoting the hydration of cement, promising the integration of aggregate and cement, and its compressive strength reaches 20.5 MPa.

Among several fruits, mangaba (Hancornia speciosa Gomes), it aroused the interest of producers and consumers due to its attractive sensory characteristics and health beneficial properties (high nutritional value and presence of bioactive substances), thus, this work evaluates the nutritional factors of the flour residue of mangaba processing that is despised by the food industry, and the influence of temperature on its production. The mangaba processing residue was splited in two main groups: in natura sample (control), and other for preparation of flour that was dried at 50 °C and divided into two other groups: treatment A (flour with roasts at 110 °C and 130 °C) and treatment B (flour from drying at 50 °C). The nutritional characteristics of flours were analyzed considering the chemical parameters: pH, titratable total acidity and soluble solids, in addition to the determination of moisture content, total lipids, total dietary fiber and ash, total energy value, antioxidant activity, phytochemical screening, quantification of phenolic compounds and flavonoids, as well as technological functional properties (water absorption index (WAI), water solubility index (WSI), milk absorption index (MAI) and milk solubility index (MSI) and oil absorption index (OAI). The results showed that the bioactive compounds present in the extracts do not have significant properties of acting as free radical kidnappers. The heat treatment, performed in the flour of mangaba processing residues, influenced the nutritional factors and properties of absorption and solubility, which showed statistical differences. These results show that the flour is a viable alternative for the energy enrichment of diets, contributing to the development of new products, the reduction of the disposal of these residues and consequently to the minimization of the environmental impact. Resumo Dentre as diversas frutas a mangaba (Hancornia speciosa Gomes), despertou interesse de produtores e consumidores devido às suas características sensoriais atrativas e propriedades benéficas à saúde (elevado valor nutricional e presença de substâncias bioativas), assim, o trabalho avaliar os fatores nutricionais do resíduo da farinha de processamento de mangaba que é desprezado pela indústria alimentícia e, a influência da temperatura na sua produção. O resíduo de processamento da mangaba foi dividido em dois lotes, sendo um deles utilizado para as análises in natura (amostra controle) e o outro para a confecção da farinha que foi seca a 50 °C, e dividida em dois lotes: tratamento A (farinha com torras a 110 °C e 130 °C) e no tratamento B (farinha oriunda da secagem a 50 °C). Analisou-se as características nutricionais de farinhas considerando os parâmetros químicos: pH, acidez total titulável e sólidos solúveis, além da determinação do teor de umidade, lipídios totais, fibra alimentar total e cinzas, valor energético total, atividade antioxidante, triagem fitoquímica, quantificação de compostos fenólicos e flavonoides, bem como as propriedades funcionais tecnológicas (índice de absorção de água (IAA), índice de solubilidade em água (ISA), índice de absorção de leite (IAL) e índice de solubilidade em leite (ISL) e índice de absorção de óleo (IAO). Na análise foi inferido que os compostos bioativos presentes nos extratos não possuem propriedades significativas de agir como sequestradores de radicais livres. O tratamento térmico, realizado na farinha de resíduos de processamento de mangaba, influenciou nos dados dos fatores nutricionais e das propriedades de absorção e solubilidade, os quais apresentaram diferenças estatísticas. Estes resultados credenciam a farinha como uma alternativa viável para o enriquecimento energético de dietas, contribuindo para o desenvolvimento de novos produtos, a redução do descarte desses resíduos e consequentemente para a minimização do impacto ambiental.

Background: Buildings in high altitude region often face low pressure and low humidity service environment, which has a great impact on the mechanical properties and durability of cement-based materials. Objective: In this paper, the effects of nano-silica (NS) on the strength and water absorption of cement mortar exposed to the low pressure and low humidity environment were studied. Methods: Mechanical properties (compressive strength and flexural strength) and durability (water absorption) were measured. And the hydration degree of cement was tested to assist analysis. Results: The flexural strength of mortar decreased and the compressive strength increased slowly after 28 days of exposure under low pressure and low humidity environment. Especially, the introduction of 1% NS could reduce the compressive strength loss and flexural strength loss of mortar under low pressure and low humidity environment. It was also found that the water absorption of the mortar in low pressure and low humidity environment was related to the tortuous degree of the pores inside the specimen. Conclusion: The introduction of 1% NS contributed the most to the mechanical properties (compressive strength and flexural strength) and durability (water absorption) of cement mortar.

Present study aims to explore the effect of sintering temperature and dwelling time on the characteristics and morphological structure of lightweight aggregates made from dry sewage sludge and waste glass powder. The mixtures were sintered at temperatures from 1100 °C to 1200 °C at a heating rate of 10 °C/min with a dwelling time of 10, 20, and 30 min to produce lightweight aggregate samples. The thermophysical behavior of the mixtures and the physic-mechanical properties (including water absorption, particle density, and compressive strength) of the obtained lightweight aggregates were studied. The microstructure of the lightweight aggregates was also analyzed using X-ray micro-computed tomography. Results indicate that increasing the sintering temperature or extending the dwelling time will reduce the particle density and compressive strength of lightweight aggregates. Moreover, the sintering temperature and dwelling time show a considerably influence on the pore structure of lightweight aggregates, which is strongly related to the physical characteristics of the lightweight aggregates. The lightweight aggregates obtained at optimized sintering temperature of 1180 °C with an optimal dwelling time of 10 min show water absorption of 1.01%, particle density of 0.78 g/cm3, and compressive strength of 7.10 MPa, thereby meeting the standard requirement of GB/T 17431.2–2010.

The disposal of waste vehicle tires is an environmental and health problem, as their recycling is very difficult. One of the effective ways of recycling is using these tires as partial replacement of Portland cement in construction industry. In this study, a systematic experimental study (by making 810 laboratory samples) is performed on concrete made with finely ground rubber (GR) and metakaolin (MK) as partial replacements of cement to investigate the compressive strength, splitting tensile strength, flexural strength, water absorption, and dry unit weight. The main goal of this study is to achieve the optimal proportions of concrete incorporating GR and MK by maximizing mechanical strengths while minimizing the water absorption (WA) of concrete. To do so, 7 concrete mixtures containing GR are produced with 3 different cement contents: 350, 400, and 450 kg/m3 in conjunction with 2 different water-cement ratios: 0.45 and 0.50. Also, 1 concrete mix is used to optimize the concrete with hybrid blends of GR and MK by employing the response surface methodology (RSM). GR and MK are applied as partial replacements of Portland cement in ranges of 0–30 vol% and 0–20 vol%, respectively. The results show that the use of GR and MK in concrete has a significant effect on its mechanical and durability properties and, thus, reduces the cement consumption which can contribute to decreasing the negative impacts of cement production on the environment. According to the optimization results, 4.2% and 19.5 vol% replacements of cement with GR and MK, respectively, can be considered as the optimum mixture compositions of hybrid concrete to maximize compressive and splitting tensile strengths by about 1–4% and 6–8%, respectively, while minimizing WA by about 48%. Depending on the flexural strength results, the amounts are changed into 1.8% and 14.7% while the flexural strength increases by about 11%.

The world's steel production has been closer to two billion tons per year and the blast furnace slag (BFS) is the maximum solid waste during the iron-smelting and steel-making process. To conserve energy and reduce emissions, on-site treatment of BFS to produce high value-added products has become a trend. In this study, the foamed glass-ceramic (FGC) is prepared by using BFS and waste glass as the base materials and the residual heat of pre-heated furnace as the heat source to simulate the high temperature industrial waste heat. The optimal FGC shows a low apparent density of 0.67 ± 0.052 g cm−3, a high porosity of 61.49 ± 1.90%, a good compressive strength of 3.18 ± 0.11 MPa, an excellent strength-to-density ratio of 4.75 MPa cm3 g−1 and a relatively small water absorption ratio of 7.05 ± 0.95%, which could completely satisfy the application requirements in the field of building construction. Combined with the SEM, XRD and TEM results, it can be found that the new formed CaSiO3 crystals plays a bridging role between the glass phase and the ceramic phase pre-existed in the BFS, which could effectively reinforce the compressive strength. This study provides a simple and feasible route to treat solid waste by using industrial waste heat and offers a new idea to solve the similar resources, energy and environmental issues.

Much recent researches have demonstrated that the quality of freshly-harvested wheat could be improved during postharvest maturation by determinating the rheological properties. However, this process is time-consuming and complex. This study aimed to provide a rapid and convenient method for predicting wheat quality during postharvest maturation by use of GlutoPeak device. Farinograph and Extensograph were used to determine the rheological properties of four wheat samples (WT1, WT2, WT3, WT4) stored under different conditions (WT1: 15 °C, 50% RH; WT2: 20 °C 65% RH; WT3: 28 °C 75% RH; WT4: 35 °C 85% RH) for a total of 10 weeks, and GlutoPeak test was used to determine the gluten aggregation properties of the four samples. Correlation analysis was also conducted between the rheological properties and the gluten aggregation properties. Results of rheological properties showed that all Extensographic properties (dough extensibility, resistance, maximum resistance and area) of the four samples increased along with the storage time, and the Farinographic properties (water absorption, dough development time, dough stability time, and farinograph quality number (FQN)) had the same tendency, indicating that the rheological properties were improved considerably with storage time extending. The GlutoPeak curves revealed that Peak Maximum Time (PMT), Brabender Equivalents Maximum (BEM) and Energy to Maximum Torque (EnMT) of wheat flour of the four samples varied greatly, particularly the PMT and EnMT of the samples WT3 and WT4 increased remarkably. Results of correlation analysis showed that EnMT had significant correlation with water absorption and area (P

In order to develop a highly efficient, simple-preparation and renewable explosion suppressant of composite powders, the superfine NaHCO3-shell powder (S-S) composite explosion suppressant was prepared by one-step method with airflow crusher to fulfill the mechanical dry coating of shell powder by NaHCO3, which solved the contradiction between dispersion and suspension force of explosion suppressant particles. The composition optimization and performance test of S-S composite explosion suppressant were carried out with the use of 20 L explosion tank and large tubular coal dust characteristics identification instrument. The results show that when the shell powder particles are coated with NaHCO3, the overall water absorption performance of the powder is reduced, the particle agglomeration phenomenon is weakened, and the dispersion is obviously improved. With the increase of NaHCO3 ratio, the ignition sensitivity of coal dust decreases, and the time to reach the first explosion Pmax is gradually delayed, and both Pmax and (dP/dt)max decrease. With the following explanations: NaHCO3 has a significant effect on reducing (dP/dt)max due to its chemical reaction, while shell powder is beneficial to reducing the Pmax due to its physical barrier effect. The suppression effect of S-S composite explosion suppressant on coal dust explosion is far better than that of pure NaHCO3 or shell powder.

Here a starch and starch hydrogel nanocomposite and superabsorbent cotton fabric was fabricated and characterized. The optimized starch hydrogel nanocomposite was synthesized by using 0.008 M potassium permanganate, 0.7 g starch and 0.6 M sodium hydroxide at 50–55 °C. potassium permanganate as a strong and inexpensive oxidizing agent were used to potentially nano cross-link the starch molecular chains and graft the starch to cellulose molecular chains along with synthesizing manganese dioxide nanoparticles (MnO2) to further obtain antibacterial, antifungal and photocatalytic properties. The stability of products in water and the water absorption indicated the highest water content of 800% for the optimum sample. The same materials and conditions were also applied to the cotton fabric to produce a superabsorbent fabric. The simple one-step synthesis procedure, in-situ production of nanoparticles, cost-effectiveness and having desired features including photocatalytic, antibacterial properties of 93% against S. aureus, and biocompatibility make the starch hydrogel nanocomposite a suitable candidate for various applications such as agriculture, medical, textile engineering and water treatment.

PVA/gelatin/chitin ternary polymer blends, with different weight ratios, were developed and characterized by employing ATR-FTIR spectroscopy, X-ray diffractometry, and DSC, and in terms of mechanical properties, electrical characteristics, water absorption rate, and antibacterial features. The FTIR examinations indicated the physico-chemical interactions being developed upon blending. The XRD patterns showed that the crystallinity of PVA matrix changed by the presence of gelatin and chitin. The gelatin content has been found to contribute toward a better water absorption ability for the blends. Electrical conductivity measurements of the blends pointed toward an increase in conductivity with chitin content. The resistance change of the blends under different humidity levels (11–84%) was measured. The stability and response time of a humidity sensor developed from an optimized blend were also examined. The developed films showed good resistance against Gram-positive Staphylococcus aureus bacteria. The findings highlight the possibility for the fabrication of good, user-friendly antimicrobial humidity sensors from the new blend system.

Interlayer is the weakest plane of the entire roller-compacted concrete (RCC) structure and is easily deteriorated under the pressure of water and other environmental factors. Shearing force induced by the different shrinkage in interlayer part is the main reason for that poor performance of the RCC. In this paper, the deformation of RCC concrete and interlayer treatment mortar with supplementary cementitious materials (SCMs, including fly ash and silica fume) and double expansive resources admixtures (HME, containing calcium sulphoaluminate (CSA) and CaO) were studied. Deformation of concrete (produced RCC) and interlayer treatment materials was modeled and compared. Porosity characters of interlayer treatment materials and water absorption of interlayer-treated RCC samples were tested. Results showed that the HME significantly reduced the shrinkage of mortar and the deformation difference degree between layers was shortened. Modified interlayer treatment materials with HME could modify the macroscopic properties of RCC, the low porosity of interlayer and water absorption of interlayer-treated RCC was resulted. The suitable HME content is necessary in interlayer treatment materials and which could improve the performance of RCC.