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Preparation and activity research of ecological nano mineraladmixture from rice husk charcoal  [PDF]
Zhao Li, , Guo Xinli, , Ge Chuang, , Guo Liping, , Shu Xin, Liu Jiaping,
- , 2016, DOI: 10.3969/j.issn.1003-7985.2016.03.018
Abstract: The rice husk ash(RHA)and silica(SiO2)nanoparticles are prepared from rice husk charcoal(RHC)by the methods of ventilated calcining and chemical precipitation, respectively, to remove the residual carbon which is harmful to cement composites. The structures and morphologies of these products are investigated by the Fourier transform infrared spectroscopy, X-ray diffraction, scanning/transmission electron microscopy and N2 adsorption-desorption analyzer. The results show that the as-produced RHA and SiO2 nanoparticles exist in amorphous phase without residual carbon, and exhibit porous structures with specific surface areas of 170.19 and 248.67 m2/g, respectively. The micro particles of RHA are aggregated by numerous loosely packed SiO2 gel particles with the diameter of 50 to 100 nm. The SiO2 nanoparticles are well dispersed with the average size of about 30 nm. Both the RHA and SiO2 nanoparticles can significantly reduce the conductivity of saturated Ca(OH)2 solution and increase the early strength of the cement composites. They also exhibit high pozzolanic activity, indicating that they can be used as ecological nano mineral admixtures.
The Different Expressions of Draft Cherry Tomato Growth, Yield, Quality under Bamboo and Rice Husk Biochars Application to Clay Loamy Soil  [PDF]
Tran Thi Thu Hien, Yoshiyuki Shinogi, Tomoyuki Taniguchi
Agricultural Sciences (AS) , 2017, DOI: 10.4236/as.2017.89068
Abstract: This study evaluated the different expressions of cherry tomato growth, yield and quality under bamboo and rice husk biochar applications to soil. The experiment was conducted under glasshouse conditions at Hakozaki campus, Kyushu University, Japan and consisted of 5 treatments, namely 1) no biochar application as a control; 2) 2% (RH2) and 3) 5% (RH5) of rice husk biochar; 4) 2% (BB2) and 5) 5% (BB5) of bamboo biochar. Bamboo biochar application significantly improved tomato growth, including number of leaves, fresh biomass yield of aboveground and underground parts for BB5; number of fruit; fresh yield from 24% - 25% for BB2 and BB5. In particular, both bamboo and rice husk biochar application at two rates 2% and 5% had positive effects on tomato quality, demonstrated by the increased total sugar content from 56% to 91%, and the enhancement of ascorbic acid content for BB2 and RH2 by 12% and 17%, respectively. Those improvements reflected the soil physiochemical property changes after biochar application, including the increase in plant available water for bamboo biochar amendment before and after cultivating by 25% - 38% and 9% - 18%, respectively, compared with those of control; and the increased total soil N for bamboo biochar treatments (11% - 14%). Generally, all data above support bamboo biochar utilization for the purpose of improving soil properties and developing crop production.
Consolidation Characteristics of Highly Plastic Clay Stabilised With Rice Husk Ash
Dr. Ashwani Jain,Er. Nitish Puri
International Journal of Soft Computing & Engineering , 2013,
Abstract: One-dimensional consolidation tests have been conducted to study the effect of addition of various percentages of rice husk ash on compressibility characteristics of highly plastic clay soil. Statically compacted soil specimens have been prepared at optimum moisture content and maximum dry density by adding 4, 8, 12, 16 and 20% by weight of rice husk ash to the parent soil. Specimens have been subjected to increments of vertical pressure of 0.25, 0.50, 1.00, 2.00 and 4.00 kg/cm2 in a fixed ring consolidometer. It has been observed due to the addition of rice husk ash to the parent clay, the optimum moisture increases and maximum dry density decrease with increase in percentage of rice husk ash. Coefficient of compressibility (av) and coefficient of volume compressibility (mv) show no significant trend for variation in values with change in proportion of rice husk ash in the soil at a particular effective stress. It has been observed that there is decrease in the values of these parameters with increase in effective stress for a particular percentage of rice husk ash. Compression index (Cc) has been found to decrease significantly with increase in percentage of rice husk ash, hence decreasing consolidation settlement of parent material. It has also been observed that the time required for achieving a given degree of consolidation decreases with increase in the percentage of rice husk ash at a particular effective stress. Overall, it has been observed that rice husk ash effectively increase one-dimensional stiffness and therefore, reduce settlement.
Rice Husk Biochar for Rice Based Cropping System in Acid Soil 1. The Characteristics of Rice Husk Biochar and Its Influence on the Properties of Acid Sulfate Soils and Rice Growth in West Kalimantan, Indonesia  [cached]
Agusalim Masulili,Wani Hadi Utomo,Syechfani MS
Journal of Agricultural Science , 2010, DOI: 10.5539/jas.v2n1p39
Abstract: The experiments were carried out to study the characteristics of biochar made from rice husk and its potential as a soil amendment in acid soils. Biochar was produced by pyrolysis; after which it was applied as a soil amendment. The soil was incubated for 30 days, and then it was planted with rice. For comparison, soil was applied with: rice straw, rice husk, rice husk ash, Chromolaena odorata biomass, and no soil amendment. The characteristics of biochar were: water content 4.96%, pH 8.70, C 18.72%, P 0.12%, CEC 17.57cmol kg-1, K 0.20%, Ca 0.41%, Mg 0.62%, and Na 1.40%. Application of biochar decreased soil bulk density, soil strength, exchangeable Al, and soluble Fe and increased porosity, available soil water content, C-organic, soil pH, available P, CEC, exchangeable K, and Ca. Out of these improvements, only soil carbon, phosphorus, exchangeable Al, soluble Fe, and soil strength significantly influenced rice biomass.
Moneeza Abbas,Muhammad Atiq-ur-Rahman,Farkhanda Manzoor,Afshan Farooq
Pure and Applied Biology , 2012, DOI: nil
Abstract: The present study was conducted to perform quantitative analysis and comparison of Nitrogen, Potassium and Phosphorus contents in rice husk and wheat bran samples. Rice and wheat are leading staple food and are cultivated in Pakistan at large scale. During refining process the rick husk and wheat bran are removed from rice and wheat grains. Both rice husk and wheat bran contain nutrients in specific proportion, that’s why these can be used effectively for different purposes such as soil amendment and organic fertilizer to retain yield and increase soil fertility. In this study the detection of Nitrogen in rice husk and wheat bran samples was done by using elemental analyzer, Potassium detection was done by using Atomic Absorption Spectrophotometer and Phosphorus was detected by using X-Ray Fluorescence Spectrometry. The result of this study shows that rice husk contains more Nitrogen (0.476±0.0687) and Phosphorus (0.0504±0.007211) contents as compared to wheat bran (0.410±0.0679) and (0.0101±0.00387) respectively. However in wheat bran, Potassium content (26.706±2.47) was slightly higher than rice husk (25.986±1.573). It can be concluded that rice husk contains comparatively more nutrient value as eco-friendly organic fertilizer than wheat bran.
Utilization Of Rice Husk Ash  [PDF]
S. D. Nagrale
International Journal of Engineering Research and Applications , 2012,
Abstract: India is a major rice producing country, and the husk generated during milling is mostly used as a fuel in the boilers for processing paddy, producing energy through direct combustion and / or by gasification. About 20 million tones of Rice Husk Ash (RHA) is produced annually. This RHA is a great environment threat causing damage to the land and the surrounding area in which it is dumped. Lots of ways are being thought of for disposing them by making commercial use of this RHA. RHA can be used as a replacement for concrete (15 to 25%).This paper evaluates how different contents of Rice Husk Ash added to concrete may influence its physical and mechanical properties. Sample Cubes were tested with different percentage of RHA and different w/c ratio, replacing in mass the cement. Properties like Compressive strength, Water absorption and Slump retention were evaluated.
The Use of Rice Husk Ash in Low - Cost Sandcrete Block Production  [cached]
Leonardo Electronic Journal of Practices and Technologies , 2006,
Abstract: The compressive strength of some commercial sandcrete blocks in Minna, Nigeria was investigated. Rice Husk Ash (RHA) was prepared using Charcoal from burning firewood. Preliminary analysis of the Constituent materials of the ordinary Portland Cement (OPC) / Rice Husk Ash (RHA) hollow sandcrete blocks were conducted to confirm their suitability for block making. Physical test of the freshly prepared mix was also carried out. 150mm′450mm hollow sandcrete blocks were cast cured and crushed for 1, 3, 7, 14, 21, and 28 days at 0, 10, 20, 30, 40 and 50 percent replacement levels. Test results indicate that most commercial sandcrete blocks in Minna town are below standard. The compressive strength of the OPC/RHA sandcrete blocks increases with age at curing and decreases as the percentage of RHA content increases. The study arrived at an optimum replacement level of 20%
Allelopathy of Rice Husk on Barnyardgrass  [PDF]
Jonghan Ko,Seok Hyun Eom,Myong Jo Kim,Chang Yeon Yu
Journal of Agronomy , 2005,
Abstract: Research efforts in seeking allelopathic compounds play an important role in developing natural herbicides. The objective of this research was to investigate the allelopathic effects of rice (Oryza sativa L.) husk extracts and to bioassay allelopathic compounds. The husk extracts of seven rice varieties were used to examine allelopathic effects on the growth of barnyardgrass (Echinochloa crusgalli (L.) Beauv.). After that, allelopathic substances effective on the growth of barnyardgrass were sought using an open chromatography and analyzed using a GC/MS. Husk extract from Ilpum rice (a national variety in South Korea) showed the prominent allelopathic effect on barnyardgrass. The organic compounds analyzed by the GC/MS were found to be 9-octadecenoic acid; 7-octadecenoic acid; 5, 8, 11-heptadecatriynoic acid and androstan-17-one. The minimum inhibition concentration of the isolated allelochemical compounds was 50 ppm. The results suggest that there is a possibility of developing a rice husk oriented natural herbicide effective on barnyardgrass.
Silica from Rice Husk Ash as an Additive for Rice Plant  [PDF]
Magale K.D. Rambo,Andre L. Cardoso,Daiane B. Bevilaqua,Tiele M. Rizzetti
Journal of Agronomy , 2011,
Abstract: The motivation for this study was to find a possible economic alternative for the residual Rice Husk Ash (RHA) as well as a way to mitigate the growing environmental problem in Southern Brazil (illegal deposition of exceeding rice husks and RHA). For this, an investigation was carried out into the preparation of two kinds of xerogel silicas from micronised rice husk ash and their utilisation as additives in the cultivation of rice. The effect of the parameters of silica extraction was evaluated by means of Response Surface Methodology and the maximal yields were 96 and 98%. The silicas were characterised in terms of their chemical composition, particle size distribution and surface area. High values for specific surface area, 183.73 and 232.42 m2 g-1 and mean particle size of 67.93 and 28.41 m, were found for the potassium-and sodium-based silicas, respectively. The effect of Si on rice production was studied under conditions of soil samples containing low concentrations of Si, with addition of 0, 100, 200 and 400 kg Si ha-1. The Si content of the soil samples increased with the increase in the dose of both silicas, causing an increase in grain yield.
Effect of Rice Husk Ash on Cement Stabilized Laterite  [cached]
Musa ALHASSAN,Alhaji Mohammed MUSTAPHA
Leonardo Electronic Journal of Practices and Technologies , 2007,
Abstract: Laterite soil collected from Maikunkele area of Minna, classified as an A-7-6 on AASHTO classification, was stabilized with 2-8% cement by weight of the dry soil. Using British Standard Light (BSL) compaction energy, the effect of Rice Husk Ash (RHA) on the soil was investigated with respect to compaction characteristics, California Bearing Ratio (CBR) and Unconfined Compressive Strength (UCS) tests. Results obtained, indicate a general decrease in Maximum Dry Density (MDD) and increase in Optimum Moisture Content (OMC), all with increase in RHA Content (2-8%) at specified cement contents. There was also a tremendous improvement in the CBR and UCS with increase in the RHA content at specified cement contents to their peak values at between 4-6% RHA. The UCS values also improved with curing age. This indicates the potentials of using 4-6% RHA admixed with less cement contents for laterite soil stabilization.
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