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This article describes the use of recycled glass sand in the production of autoclaved products. Traditional autoclaved bricks consist of crystalline sand, lime and water. The conducted research aimed at the complete elimination of quartz sand in favor of glass sand. This work focuses on porosity as the functional property of the materials. The aim of this article is to determine the number and structure of the pores of autoclaved bricks. Two types of research were carried out: (a) non-destructive, i.e., computed tomography examination as a pictorial and quantitative method and (b) mercury porosimetry as a quantitative method, i.e., a test that exposes the porous skeleton of the material for destruction. The tests showed the presence of pores with a size in the range of 0.1 ÷ 100 μm, and the volume of voids in the material was determined at the level of about 20% for the sample modified with glass sand (GS) and for the reference sample made of traditional silicate brick. In order to complete the research on the internal structure of autoclaved bricks, microstructure studies were performed using a scanning electron microscope (SEM). The tests showed the presence of tobermorite in the reference sample (with 90% QS-quartz sand) and the presence of natrolite and gyrolite in the sample modified by glass sand (90% GS).

This paper describes the use of glass sand in the production of autoclaved bricks. Traditional autoclaved materials consist of SiO2, CaO, and H2O. The purpose of the tests is to analyze the possibility of using glass sand in autoclaved materials and to determine their properties and durability. Depending on the structure, building materials can have porosities ranging from 0% (glass, metals) to over 90% (thermal insulation materials such as aerated concrete). Porosity of materials is directly related to the strength of materials and their density, and further to the thermal and acoustic insulation properties of products used especially for external wall construction, i.e., bricks, concrete, and aerated concrete. This type of silicate brick is formed at a temperature of 203 °C, therefore the dominant phase forming the microstructure is tobermorite, in contrast to the C-S-H phase, which dominates in concretes and which is characterized by a larger specific surface. The nature of pores, their number, appearance and arrangement in the material can be studied using computer techniques (SEM, XRD, computed tomography, porosimetry). Computed tomography (micro-CT analysis) showed that the number of voids in the material modified by glass sand is about 20% in relation to the weight of the product. The density of the product with glass sand was determined to be 2.2 kg/dm3.

The assessment of water-extractable organic matter using an autoclave can provide useful information on physical, chemical, and biological changes within the soil. The present study used virgin forest soils from Chini Forest Reserve, Langkawi Island, and Kenyir Forest Reserve (Malaysia), extracted using different extraction methods. The dissolved organic carbon (DOC), total dissolved nitrogen (TDN), total dissolved phosphorus (TDP), and ammonium-nitrate content were higher in the autoclave treatments, up to 3.0, 1.3, 1.2, and 1.4 times more than by natural extraction (extracted for 24 h at room temperature). Overall, the highest extractable DOC, TDN, TDP, ammonium and nitrate could be seen under autoclaved conditions 121 °C 2×, up to 146.74 mg C/L, 8.97 mg N/L, 0.23 mg P/L, 5.43 mg N mg/L and 3.47 N mg/L, respectively. The soil extracts became slightly acidic with a higher temperature and longer duration. Similar trends were observed in the humic and nonhumic substances, where different types of soil extract treatments influenced the concentrations of the fractions. Different soil extraction methods can provide further details, thus widening the application of soil extracts, especially in microbes.

This paper adopts an experimental approach on the use of rice husk ash as a partial replacement of cement in the production of concrete and the consequent effects on density, compressive strength and split tensile strength of the formulated product. Rice husk ash is used as replacement of cement in different dosages of 0%, 2.5%,5%, 7.5%, 10%, 12.5%, and 15%. Results showed that 10% replacement of cement with rice husk ash is optimum. At 10% replacement of cement with RHA, the density is increased by 5.02%, the compressive strength by 22.22% and the split tensile strength by 20.45% in comparison with control aerated concrete.

The use of environmental and sustainable ornamental flower production practices with renewable resources has drawn worldwide interest. One of these renewable resources is vermicompost (earthworm castings). In recent years, increasing demand for improving environmental quality have focused on the importance of Plant Growth Promotion Bacteria (PGPBs) in agriculture. Vermicomposts also help microbial agents function effectively in soil. In this study, a total of six treatments [A: PGPB formulation, B: Not autoclaved vermicompost, C: Autoclaved vermicompost, D: Not autoclaved vermicompost+PGPBs, E: Autoclaved vermicompost+PGPBs, F: Control (untreated bacteria and vermicompost)] were tested for their effects on the plant growth and development parameters in gladiolus (Gladiolus grandiflorus L. ‘Red Beauty’) in greenhouse condition. Vermicompost was added to the related pots by dissolving in water. After the addition of vermicompost, PGPB formulation was given immediately to related pots. All the treatments were applied to soil once in three leaf stage, close to the plant root zone. Parameters in terms of yield and quality attributes of plant and corm were determined and analyzed. The treatment A increased in plant height of gladiolus of 24.55% rate. The earliest times to flowering was determined in E application (100.48 day), which also increased in corm diameter with rate of 17.41% and number of corms and cormels with rate of 151.83% according to F application. Results indicated that the treatment E promoted overall better performance as compared to other treatments diameter of flowers for number of leaves per plant, number of florets per spike, stem diameter, spike length, fresh and dry weight of flowers, the number and diameter of corm. Autoclaved vermicompost can be good choice in gladiolus cultivation but it should be enriched with PGPB.

Anadolu Üniversitesi ve Bilecik Şeyh Edebali Üniversitesi tarafından ortak yürütülen program. Geleneksel gazbeton ince öğütülmüş silis kumu (kuvars kumu) ve bağlayıcı malzemeden (kireç, çimento) oluşan karışıma gözenek oluşturan bir katkı malzemesi ilave edilmesi ile hafifleşen ve basınçlı buhar kürü ile dayanım kazanan bir hafif betondur. Farklı doğal ve yapay mineral malzemelerin gazbeton karışımlarında kullanımı, ürün çeşitliliği ve üretimde ekonomi sağlayacaktır. Bu çalışmada, gazbeton üretiminde riyolit, perlit ve uçucu külün mineral katkı olarak kullanılabilirliği ve gazbeton özelliklerine etkisi araştırılmıştır. G2/05 gazbeton sınıfı esas alınarak iki grup altında dört farklı referans gazbeton karışım oranları belirlenmiştir. Her bir grup karışımlarda alüminyum, sönmüş kireç, alçı ve su/katı oranı sabit tutulmuştur. İlk grup çalışmada, 3 farklı referans gazbeton karışımında her bir mineral katkı %25, %45, %65 ve %85 oranlarında çimento ile yer değiştirilerek kullanılmıştır. İkinci grup çalışmada, referans karışım olarak sadece her bir mineral katkının %76 oranında kullanıldığı üretimler yapılmıştır. Bu grupta referans karışıma, 3 farklı oranda çimento (%20, %40, %60) ve silis kumu (%30, %50, %70) mineral katkı ile yer değiştirilerek ilave edilmiştir. Gazbeton bileşen miktarları, toplam katı malzeme miktarına göre belirlenmiştir. Üretilen gazbeton numuneleri, 40°C'de 4 saat kabarma için bekletildikten sonra 180°C ve 12 bar basınçta 6 saat otoklavda kür uygulanmıştır. Gazbeton numunelerde yayılma, penetrasyon, basınç, kuru birim hacim ağırlık, kılcal su emme ve ısı iletkenlik deneyleri yapılmıştır. Ayrıca SEM ve XRD analizleri gerçekleştirilmiştir. Deney sonuçlarına göre, perlit, riyolit ve uçucu kül katkılı gazbeton numunelerde sırasıyla 2.16-2.57 MPa, 2.24-2.41 MPa ve 2.04-2.53 MPa aralığında basınç dayanımı değerleri elde edilmiştir. Çimentosuz, sadece mineral katkıların kullanıldığı karışımlarda gazbeton numunesi elde edilememiştir. Anahtar Kelimeler: Gazbeton; Perlit, Riyolit; Uçucu Kül; Basınç Dayanımı Conventional gas concrete is a lightweight concrete that is lightened by adding a pore-forming additive to the mixture of finely ground silica sand (quartz sand) and binder material (lime, cement) and which becomes stable by pressurized steam curing. The use of different natural and artificial mineral materials in aerated concrete mixes will provide product variety and economy in production. In this study, the usability of rhyolite, perlite and fly ash as a mineral additive in gas concrete production and its effect on aerated concrete properties were investigated. Based on the G2/05 gas concrete class, four different reference gas concrete mixture ratios were determined under two groups. Aluminum, slaked lime, gypsum and water/solid ratio were kept constant in each group mixtures. In the first group study, each mineral additive was used by replacing 25%, 45%, 65% and 85% cement in 3 different reference gas concrete mixes. In the second group study, productions that only 76% of each mineral additive was used as the reference mixture were made. In this group, 3 different ratios of cement (20%, 40%, 60%) and silica sand (30%, 50%, 70%) were added to the reference mixture by replacing with mineral additive. The amounts of aerated concrete components were determined according to the total amount of solid material. The produced gas concrete samples were allowed to swell at 40° C for 4 hours and then cured in autoclave at 180°C and 12 bar pressure for 6 hours. Spread, penetration, pressure, dry unit volume weight, capillary water absorption and thermal conductivity tests were performed on the gas concrete samples. SEM and XRD analyzes were also performed. According to the experiment results, compressive strength values of 2.16-2.57 MPa, 2.24-2.41 MPa and 2.04-2.53 MPa were obtained in perlite, rhyolite and fly ash reinforced gas concrete samples, respectively. Aerated concrete samples which producing without cement could not be obtained only in mixtures with mineral additives. Keywords: Autoclaved, Aerated Concrete; Perlite; Ryolite; Fly Ash; Compressive Strength

The present study was conducted to improve the nutritional quality of shrimp meal (SM) comprising of heads with hulls of black tiger shrimp (Penaeus monodon) waste by autoclaving and chemical treatments. The sun-dried SM was divided into 5 treatment groups, such as 1) control (untreated), 2) autoclaved (autoclaved at 121°C for 10 min), 3) NaOH (treated with 3% NaOH), 4) HCl (treated with 3% HCl) and 5) formic acid (treated with 3% formic acid) groups. After treatment, they were ground to pass through 1.0 mm mesh screen and then used for analyses of chemical composition and in vitro dry matter (DM) and CP digestibilities. Data were subjected to one-way ANOVA and differences among treatment means (P