• Asian-Australasian Journal of Animal Sciences
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• 제24권1호
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• pp.125-129
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• 2011

The aim was to determine the relationship between muscle structure and meat quality traits in neuromuscular compartments (NMCs: R1, R2, R3, R4) of pig semitendinosus muscle. Barrows from the INTA-MGC genetic line (Argentina) were slaughtered at 100 kg body weight. In each NMC the following parameters were determined: the fibre types I, IIA, IIX and IIB by immunohistochemistry, the fibre cross sectional area (FCSA), the pH of meat after 24 h post-mortem ($pH_{24}$), instrumental meat tenderness (WB) and colour ($L^*$, $a^*$, $b^*$). There were significant differences in the following: $L^*$ (R1 = R4$a^*$ (R1>R4>R2 = R3), $b^*$ (R1 = R4R1 = R3 = R4), $pH_{24}$ (R1 = R4>R2 = R3). The relative percentages of FCSA were as follows: I (R4>R1>R3>R2), IIA (R1>R4>R3>R2), IIX (R1 = R2 = R3 = R4) and IIB (R2>R3>R1>R4). The correlation values were statistically significant between IIB and WB (R1 and R4, $r_s$ = 0.66), (R2 and R3 $r_s$ = 0.74), IIB and $L^*$ (R1 and R4 $r_s$ = 0.84), IIX and $L^*$ without discriminating NMCs. Our data suggest that the NMC where the sampling takes place is important for determining meat quality traits because of the heterogeneity of the whole muscle.

• Computers and Concrete
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• 제13권6호
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• pp.709-737
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• 2014

Fibre-reinforced self-compacting concrete (FRSCC) is a high-performance building material that combines positive aspects of fresh properties of self-compacting concrete (SCC) with improved characteristics of hardened concrete as a result of fibre addition. To produce SCC, either the constituent materials or the corresponding mix proportions may notably differ from the conventional concrete (CC). These modifications besides enhance the concrete fresh properties affect the hardened properties of the concrete. Therefore, it is vital to investigate whether all the assumed hypotheses about CC are also valid for SCC structures. In the present paper, the experimental results of short-term flexural load tests on eight reinforced SCC and FRSCC specimens slabs are presented. For this purpose, four SCC mixes - two plain SCC, two steel, two polypropylene, and two hybrid FRSCC slab specimens - are considered in the test program. The tests are conducted to study the development of SCC and FRSCC flexural cracking under increasing short-term loads from first cracking through to flexural failure. The achieved experimental results give the SCC and FRSCC slabs bond shear stresses for short-term crack width calculation. Therefore, the adopted bond shear stress for each mix slab is presented in this study. Crack width, crack patterns, deflections at mid-span, steel strains and concrete surface strains at the steel levels were recorded at each load increment in the post-cracking range.

• Steel and Composite Structures
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• 제22권3호
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• pp.497-520
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• 2016

The confined concrete stress-strain curves utilised in computational models of concrete-filled steel tubular (CFST) columns can have a significant influence on the accuracy of the predicted behaviour. A generic model is proposed for predicting the stress-strain behaviour of confined concrete in short circular, elliptical and octagonal CFST columns subjected to axial compression. The finite element (FE) analysis is carried out to simulate the concrete confining pressure in short circular, elliptical and octagonal CFST columns. The concrete confining pressure relies on the geometric and material parameters of CFST columns. The post-peak behaviour of the concrete stress-strain curve is determined using independent existing experimental results. The strength reduction factor is derived for predicting the descending part of the confined concrete behaviour. The fibre element model is developed for the analysis of circular, elliptical and octagonal CFST short columns under axial loading. The FE model and fibre element model accounting for the proposed concrete confined model is verified by comparing the computed results with experimental results. The ultimate axial strengths and complete axial load-strain curves obtained from the FE model and fibre element model agree reasonably well with experimental results. Parametric studies have been carried out to examine the effects of important parameters on the compressive behaviour of short circular, elliptical and octagonal CFST columns. The design model proposed by Liang and Fragomeni (2009) for short circular, elliptical and octagonal CFST columns is validated by comparing the predicted results with experimental results.

• KSBB Journal
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• 제6권2호
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• pp.135-141
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• 1991

This study thus looks into two treatment processess : i) Anaerobic digester coupled with hollow fibre membrane unit. Treatment of starch waste with anaerobic digester-membrane system was studied. $0.17\m^2$ area of hollow fibre membrane unit of known pore size was immersed into laboratory-scale anaerobic digestion system. The pore size of membrane was varied from 0.03 to $\0.15mu$m. The hydraulic retention time of anaerobic digester was varied from 1.5 to 10 days. The effect of hydraulic retention time on treatment efficiency was significant while effect of membrane size was not significant. The gas production was about 0.74㎥/kg COD treated. The COD removal efficient was about 80-95% depending on the hydraulic retention time. ii ) Crossflow ultrafiltration as post treatment to anaerobic filter. The effluent from anaerobic filter, which had a total COD in the range of 4,500-5,200 mg/L was treated by crossflow ultrafiltration units. The study conducted with different membrane pore size indicated that membrace with 1,000,000 molecular weight cut-off size gave a higher COD removal efficiency in the range of 83-87% while giving a study flux of $120-130 L/\m^2$.h. A study was conducted to see the long term clogging effect of membrane also.

• Asian-Australasian Journal of Animal Sciences
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• 제16권11호
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• pp.1610-1613
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• 2003

The aim of the experiment was to study the changes in the activities of various rumen fibre degrading enzymes due to the feeding of chemically treated mustard (Brassica campestris) straw in sheep. Mustard straw (MS) (<5 cm particle size) was treated either with urea (4% (w/w), or with 2% sodium hydroxide (NaOH), or with alkaline hydrogen peroxide (2% NaOH and 1.5% hydrogen peroxide ($H_2O_2$)) and/or supplemented with 2% (w/w) urea. Seven maintenance type rations were prepared using MS (70 parts) with molasses (5 parts) and concentrate (25 parts). They were untreated MS (CMS), urea treated MS (UMS), urea supplemented MS (MSUS), alkali treated MS (AMS), alkali treated and urea supplemented MS (AMS-US), alkali $H_2O_2$ treated MS (AHMS) and alkali $H_2O_2$ treated and urea supplemented MS (AHMS-US). They were then compressed into a complete feed block with the help of block making machine. Forty two male hoggets of Malpura breed sheep were equally distributed into each treatment group and (were) offered feed and water ad libitum. At the end of 21 days of feeding trial, rumen liquor was collected through stomach tube from three animals in each group at 0 h, 4 h, 8 h, 12 h of post feeding. Results showed that the level of enzyme varied from 8.52 to 11.12, 40.85 to 50.37, 3.22 to 3.78, 2.09 to 2.77 and 31.44 to 44.24 units/100 ml SRL respectively for carboxymethyl cellulase (CMCase), $\alpha$-amylase, microcrystalline cellulase (MCCase), filter paper (FP) degrading enzyme and $\alpha$-glucosidase. Processing of MS affected the enzyme activities, in a way, that NaOH and AHP treatment significantly reduced CMCase and FP degrading enzyme. The effect of urea treatment showed an increase in the activity of MCCase and $\alpha$-glucosidase. But the supplementation of urea increased the activity of CMCase, FP degrading enzyme and $\alpha$-glucosidase. The CMCase, $\alpha$-amylase, $\alpha$-glucosidase activities were highest at 4hr whereas MCCase and FP degrading enzyme had maximum activities at 12 h post feeding Results suggested that MS might need longer time in the rumen for its effective degradation.

• Asian-Australasian Journal of Animal Sciences
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• 제15권2호
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• pp.283-289
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• 2002

A comparative study on the quality of meat from three breeds of goats reared in Bulgaria: Local Aboriginal (LA); Bulgarian White Dairy (BWD) and crossbreeds of local aboriginal with Saanen goats (LA ${\times}$ S). Eight intact young male goats from each breed have been included in the experiment. The animals from the three breeds have been reared under similar conditions. The animals have been slaughtered at the age of 2 months (at weaning) and at the age of 6 months (upon reaching sexual maturity). The following tests have been performed on samples of m. longissimus dorsi between $5^{th}$ and $6^{th}$ ribs: pH 45 min post mortum, colorimetrically color of meat, water holding capacity and fatty acid composition of the fat. The thickness of muscle fibre and the proportion of muscle, connective and adipose tissue have been microscopically determined at m. longissimus dorsi, m. semitendinosus and m. iliopsoas. After deboning and separating the bigger tendons, the chemical composition of the meat from the left half of the carcass has been determined. The results reveal lack of statistically significant differences among the three breeds concerning pH, the water holding capacity, color of meat, thickness of the muscle fibre and fatty acid composition of the fat. The carcass meat of crossbreeds of LA ${\times}$ S contains significantly more fat than the other two breeds. This influences the proportion of muscle, connective and adipose tissue in m. longissimus dorsi, m. semitendinosus and m. iliopsoas, resulting in more adipose tissue in the LA ${\times}$ S compared to young goats of the LA or the BWD. There are differences in slaughtering 2-month-old goats (at weaning) and 6-month-old ones (upon reaching sexual maturity). At a greater age the content of fat in the carcass increases, as well as the quantity of the adipose tissue, the intensity of the colour of the meat and there is a tendency towards thickening of the muscle fibre and increasing the water holding capacity of meat. The moisture content in meat decreases due to the increase of fat.

• 대한치과의사협회지
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• 제48권9호
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• pp.680-687
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• 2010

The purpose of this study was to compare post cementation efficacy according to the different adhesive systems and cement delivery methods. A total of 40 extracted human single-rooted premolar teeth were randomly divided in four groups according to the two luting agents of Unicem applicap (3M ESPE, St. Paul, MN, USA) or Variolink II (Ivoclar Vivadent, Liechtenstein) and cement delivery methods of direct cement application or lentulo spiral application. After restoration using glass?fiber posts, the samples were embedded in acrylic resin. Three sections of 2 mm thickness were prepared from each specimen, and the post in each section was subjected to a push-out test. The data were analysed statistically at significant level of 95%. The Unicem had significantly higher push-out bond strength than Variolink and the lentulo spiral application made higher bond strength (p<0.05). Adhesive failure between cement and dentin was predominant in all groups. The Unicem of self-etch system and cement delivery using lentulo spiral showed clinically acceptable and comparable bonding strength for the fiber post.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2002년도 정기총회 및 제29차 춘계국제 학술발표대회
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• pp.17-25
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• 2002

Application of electrical stimulation in the red meat species (eg. beef and sheep) processing has been erratic around the world and this may reflect an incomplete knowledge of how to optimise the technology. Although it is well established that stimulation increases the rate of post-mortem glycolysis other biochemical and biophysical effects have been implicated with the use of this technology. On the basis of currently available knowledge, this mini-review seeks to examine the current theories about the effect of stimulation on post-mortem muscle. The classical view that stimulation prevents muscle from shortening excessively during rigor development has been expanded to include the possibility that it also results in physical disruption of muscle structure. The interaction of these effects with the acceleration of the rate of proteolysis through activation of the calpain protease system has not been comprehensively reviewed in the past. As a result of conclusion driven, this article highlights several areas that may prove fruitful for further research. The challenge for further development of electrical stimulation systems is optimisation of the activation of the enzyme systems in parallel with manipulation of chilling regimes so as to ensure rigor mortis is achieved at temperatures which minimise shortening. The potential of regional stimulation of sections of the carcass to achieve this outcome is worthy of study given the different fibre composition of muscles and temperature gradients.

• 한국재료학회지
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• 제3권2호
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• pp.140-144
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• 1993

열경화성 에폭시 수지의 물성 중 담약성을 개선하기 위해 새로운 반응성첨가제 succinonitrile(SN)을 Diglycidy1 ether of bisphenol A(DGEBA(-4,4'-methylene dianiline(MDA)계에 도입하여 현재 널리 사용되고 있는 유리섬유 복합재료에 매트릭스로 사용될 경우에 있어서 파괴되는 거동을 미시적으로 고찰하였다. 그 결과 post debond friction 에너지가 파괴 거동을 주도하고 있으며, 다음으로 pull-out에너지 그리고 debonding 에너지 순으로 나타났다. 따라서 파괴 거동에 미치고 있는 중요한 요인은 섬유와 매트릭스 간의 경계면 전단 응력이 크게 좌우함을 알 수 있었으며, 이때 반응성 첨가제 SN은 전단응력을 떨어뜨리는 것으로 고찰되었다.

• Steel and Composite Structures
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• 제33권6호
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• pp.849-864
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• 2019

One way to achieve sustainable construction is to reduce concrete consumption by use of more sustainable and higher strength concrete. Modern building codes do not cover the use of ultra-high strength concrete (UHSC) in the design of composite structures. Against such background, this paper investigates experimentally the mechanical properties of steel fibre-reinforced UHSC and then the structural behaviors of UHSC encased steel (CES) members under both concentric and eccentric compressions as well as pure bending. The effects of steel-fibre dosage and spacing of stirrups were studied, and the applicability of Eurocode 4 design approach was checked. The test results revealed that the strength of steel stirrups could not be fully utilized to provide confinement to the UHSC. The bond strength between UHSC and steel section was improved by adding the steel fibres into the UHSC. Reducing the spacing of stirrups or increasing the dosage of steel fibres was beneficial to prevent premature spalling of the concrete cover thus mobilize the steel section strength to achieve higher compressive capacity. Closer spacing of stirrups and adding 0.5% steel fibres in UHSC enhanced the post-peak ductility of CES columns. It is concluded that the code-specified reduction factors applied to the concrete strength and moment resistance can account for the loss of load capacity due to the premature spalling of concrete cover and partial yielding of the encased steel section.