• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.1
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• pp.92-98
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• 2000

This study is performed to evaluate the elastic properties of rice straw ash concrete using reices straw ash, cement, natural sand, gravel, and superplasticizer. The following conclusions are drawn ; The ultrasonic pulse velicity is in the range of 4,084 ~4,336m/s , which has showed about the same compared to that of the normla cement concrete. The highest ultrasonic pulse velocity is showed by 5 % rice straw ash filled rice straw ash concrete. The dynamic and static modulus of elasticity is in the range of 294 $\times$10$^3$ ~347 $\times$ 10$^3$ and 266 $\times$10$^3$~328 $\times$10$^3$kgf/㎤ , respectively. It is showed about the same compared to that of the normal cement concrete. The Poisson's number of rice straw ash concrete is less than that of the normal cement concrete.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.5
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• pp.523-527
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• 1995

Two on farm feeding trials were conducted at the Pabna milkshed area during July to October 1993, to evaluate the response of feeding urea molassesed straw (UMS) on milk production of Pabna milking cows and its economics. A feeding trial of 60 days with 50 Pabna milking cows showed that the cows fed UMS as a replacer of dry straw increased daily milk yield by 1.37 litre. Moreover, it reduced the daily requirement of concentrate by 1.0 kg/head. In the second trial, a herd of 52 animals including 14 milking cows were fed UMS in place of traditionally used dry straw. Introduction of UMS increased the milk production by 1.0 litre/cow/day and saved concentrate by 1.5 kg/cow daily. Urea molassesed straw can safely and economically be fed to lactating cows.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.232-238
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• 1999

The reinforcement of wheat straw pulp sheets with softwood kraft was studied, with special emphasis on the impact of softwood kraft beating and the proportion softwood kraft in straw pulp. the reinforcement was evaluated by measuring the tensile stiffness sand in-plane fracture behavior of samples. the results were compared with a mechanical pulp (TMP) and with a hardwood birch kraft, both reinforced with the same softwood kraft. Wheat straw pulp forms strong interfiber bonds. Therefore, its tensile stiffness and tensile strength are larger than TMP used. In-plane tear tests showed that a pure wheat straw pulp sheet has low fracture energy and correspondingly a narrow fracture process zone. The fracture energy of the reinforced straw sheets was found to increase linearly with the proportion of both unbeaten and beaten softwood pulps.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1133-1136
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• 2000

Wheat straw was treated with 4 per cent urea at a moisture level of 50 per cent alongwith different levels of boric acid viz. 1, 2, 3 and 4 per cent, under laboratory conditions to know the impact of boric acid on ammonia-N fixation in the straw. Murrah buffaloes were used for determining the disappearance of dry matter, CP and fibre constituents by nylon bag technique. Ammoniation increased CP content of wheat straw, which increased further due to addition of boric acid. Low level of boric acid (1%) had no adverse effect on fibre constituents disappearance but at higher levels there was a depressioon in the disappearance of fibre coonstituents. It can be concluded that low level of boric acid was sufficient to trap the excess ammonia released during urea ammoniation of wheat straw without affecting other constituents and their disappearance in the rumen of buffaloes.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.324-329
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• 1999

This study is performed to evaluate an elastic properties of rice straw ash concrete . The following conclusions are drawn ; The ultrasonic pulse velocity is in the range of 4.084 ∼4.336㎧, which has showed abuot the same compared to that of the normal cement concrete. The highest ultrasonic pulse velocity is showed by 5% rice straw ash filled reice straw ash concrete. The dynamic and static modulus of elasticity i sin the range of 294 ${\times}$103 ∼ 347 ${\times}$103 and 266${\times}$ 103 ∼347${\times}$ 103 kgf/$\textrm{cm}^2$ , respectively. It is showed about the same compared to that of the normla cement concrete. The poisson's number of rice straw ash concrete is less than that of the normal cement concrete . The stress-strain curve of concrete which is contained rice straw ash within 10% appear slowly and over 10% appear almost straightly.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.36-37
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• 2015

The purpose of this study is to investigate pozzolanic reactivity of the rice straw ash. This study focused on rice straw ash properties at various burning temperature and duration as a mineral admixture for mortar and concrete, and provide the crystalline state and molecular structure of rice straw ash. X.R.D and N.M.R were performed on rice straw ashes to identify pozzolanic reactivity.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.109-110
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• 2013

The purpose of this study was to investigate pozzolanic activity according to the firing temperature of the rice straw ash. In order to measure amount of SiO2 of rice straw ash, XRF(X-ray fluorescence) analysis was tested. Also to evaluate properties of mortars using rice straw ash, mortar flow, cement setting time, compressive strength was tested. As a results, as the mortar with a mixture ratio of rice straw ash up to 15% was found to have a compressive strength superior to that of plain mortar.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.3
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• pp.66-72
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• 1999

The purpose of this experiment is to estimate freezing and thawing resistance of rice straw ash concrete. Test results show that mass, pulse velocity and relative synamic modulus of elasticity are gradually decreased with increase of freezing and thawing cycle. The durability factor(DF) is in the range of 85.48 ∼86.33 in the rice straw ash comcrete with 2.5% , 5% 7.5%, rice straw ash and higher than that of thenormal cement concrete. But, DF of 10% , 12.5%, 15% rice straw ash filled rice straw ash concrete is in the range of 41.26∼65.34 and lower than that of the normal cement concrete.

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.711-717
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• 2008

To speed up the conversion of rice straw into feeds in a low-temperature region, a start culture used for ensiling rice straw at low temperature was selected by continuous enrichment cultivation. During the selection, the microbial source for enrichment was rice straw and soil from two places in Northeast China. Lab-scale rice straw fermentation at $10^{\circ}C$ verified, compared with the commercial inoculant, that the selected start culture lowered the pH of the fermented rice straw more rapidly and produced more lactic acid. The results from denatured gradient gel eletrophoresis showed that the selected start culture could colonize into the rice straw fermentation system. To analyze the composition of the culture, a 16S rRNA gene clone library was constructed. Sequencing results showed that the culture mainly consisted of two bacterial species. One (A) belonged to Lactobacillus and another (B) belonged to Leuconostoc. To make clear the roles of composition microbes in the fermented system, quantitative PCR was used. For species A, the DNA mass increased continuously until sixteen days of the fermentation, which occupied 65%. For species B, the DNA mass amounted to 5.5% at six days of the fermentation, which was the maximum relative value during the fermentation. To the authors' best knowledge, this is the first report on ensiling rice straw with a selected starter at low temperature and investigation of the fermented characteristics.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1430-1433
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• 2004

A study was conducted to determine the effect of different alkali treatments on changes in chemical composition and on degradability of bagasse and rice straw. This study divided into 2 experiments, the first with bagasse and the second with rice straw. Each experiment comprised 9 treatments which included: untreated control; 3% NaOH; 6% NaOH; 3% urea; 6% urea; 3% NaOH/3% urea; 3% NaOH/6% urea; 6% NaOH/3% urea; 6% NaOH/6% urea. In both experiments, crude protein contents were increased from 2.0 to 12.5 units for bagasse and 3.1 to 13.7 units for rice straw by urea treatments. Ash contents of the treated bagasse and rice straw were increased over the untreated control (1.5-9.7 units for bagasse; 4.2-8.8 units for rice straw). The effects on ether extract, crude fiber, neutral detergent fiber and acid detergent fiber of the treated bagasse and rice straw were variable. Nylon bag degradability of dry matter and crude fiber were increased by treatments applying NaOH and NaOH plus urea but not urea alone. In contrast, the egradability of neutral detergent fiber and acid detergent fiber were reduced compared with the untreated control. From these degradability studies, it can be concluded that the most efficient treatments of bagasse were those treatments with 6% NaOH, followed by treatments with 6% NaOH plus 3% or 6% urea and 3% NaOH plus 3% or 6% urea, respectively. However, when comparison was made on the cost of chemical used to treat the agricultural by-products, particularly in case of rice straw, 3-6% urea would be appropriate.