• Journal of Periodontal and Implant Science
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• 제42권6호
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• pp.237-242
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• 2012

Purpose: The aim of this study was to clinically and radiographically evaluate and compare treatment of intrabony defects with the use of decalcified freeze-dried bone allograft in combination with a calcium sulphate barrier to collagen membrane. Methods: Twelve patients having chronic periodontal disease aged 20 to 50 years and with a probing depth >6 mm were selected. Classification of patient defects into experimental and control groups was made randomly. In the test group, a calcium sulphate barrier membrane, and in control group, a collagen membrane, was used in conjunction with decalcified freeze-dried bone graft in both sides. Ancillary parameters as well as soft tissue parameters along with radiographs were taken at baseline and after 6 months of surgery. Parameters assessed were plaque index, modified gingival index, probing depth, relative attachment level, and location of the gingival margin. A Student's t-test was done for intragroup and a paired t-test for intergroup analysis. Results: Intragroup analysis revealed statistically significant improvement in all the ancillary parameters and soft tissue parameters with no statistically significant difference in intergroup analysis. Conclusions: The study concluded that a calcium sulphate barrier was comparable to collagen membrane in achieving clinical benefits and hence it can be used as an economical alternative to collagen membrane.

• 한국세라믹학회지
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• 제44권11호
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• pp.633-638
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• 2007

The setting time of alkali activated slag cement tends to be much faster than ordinary Portland cement, and its compressive strength had been higher from the 1 day but became lower than that of the cement on the 28 days. According to the results of the surface observation, weight loss, compressed strength, and erosion depth tests on the sulphuric acid solution. It has been drawn that alkali activated slag cement has a higher sulphate resistance than ordinary Portland cement, and in particular, the alkali activated slag cement added 5 wt% alumina cement has little deterioration on the sulphuric acid solution. The reason why the alkali activated slag cement has higher sulphate resistance than other hardened cement pastes is that it has no $Ca(OH)_2$ reactive to sulphate ion, and there is little $CaSO_4{\cdot}2H_2O$ production causing volume expansion, unlike other pastes. And it is supposed that $Al(OH)_3$ hydrates with high sulphate resistance, which is produced by adding the alumina cement increases the sulfate resistance.

• 식물조직배양학회지
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• 제28권4호
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• pp.205-208
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• 2001

벼의 종자배양에서 식물체 재분화 능력을 향상시키기 위하여 2 mg/L의 2,4-D와 여러 가지 농도의 copper (0~5.0mg/L)가 첨가된 MS배지에 종자배양 한 바 캘러스 생장정도는 copper 농도에 따라 다르게 나타났는데 특히, 2.5 mg/L의 copper가 첨가된 배지에서 가장 양호하였다. 그리고 캘러스 형성률과 copper 농도 간에는 유의성 있는 차이가 인정되지 않았다. 식물체 재분화 배지에 2.5 mg/L의 copper의 첨가는 Indica 품종들의 식물체 재분화 효율을 크게 향상시켰다. Copper가 첨가되지 않은 N$_{6}$배지에서 Indica 6품종의 평균재분화율은 2.4%이었으나, copper가 첨가된 배지에서 27.4%로 높게 나타났다.

• Environmental Engineering Research
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• 제24권1호
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• pp.24-30
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• 2019

The present study explores the applicability of response surface methodology (RSM) in conjunction with central composite design (CCD) matrix to statistically optimize ettringite crystallization process for the removal of sulphate from landfill leachate. A three factor-five coded level CCD with 20 runs, was performed to estimate the best fitted model. The RSM results indicated that the fitted quadratic regression model could be appropriate to predict sulfate removal efficiency. The pH was identified as the most dominant parameter affecting sulphate removal. 61.6% of maximum sulphate removal efficiency was obtained at pH of 11.06 for a 1.87 of $Ca/SO_4$ and 0.51 of $Al/SO_4$ molar ratios. The operating cost for ettringite crystallization at optimized conditions was calculated to be 0.52 $/$m^3$. The significance of independent variables and their interactions were tested by analysis of variance. Scanning electron microscope (SEM) and SEM coupled with energy dispersive X-Ray spectroscopy results confirmed the formation of ettringite crystal and were used to describe its morphology features.

• Fibers and Polymers
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• 제5권2호
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• pp.110-116
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• 2004

Hydrolyzable organic esters were compared with ammonium sulphate as an acid donor for the pH control in dye-bath-reuse system of acid dyes mixtures. The ability of pH control, levelness, dyeing properties and reproducibility in dye-bath-reuse system were investigated comparatively. Hydrolyzable organic esters showed higher exhaustion and color yield than ammonium sulphate. In addition, hydrolyzable organic ester exhibited very low conductivity less than 0.5 mS, while ammonium sulphate give high conductivity. However, we could not observe any difference in levelness of dyed samples between two kinds of acid donors in laboratory scale dyeing. Over 10 cycles of reuse, hydrolyzable organic esters showed higher reproducibility than ammonium sulphate. No deterioration of the color fastness and levelness occurs over 10 cycles of reuse.

• 대한방사선기술학회지:방사선기술과학
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• 제3권1호
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• pp.43-48
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• 1980

An experimental study was carried out to make a comparison between tube voltage and density of barium sulphate in the stomach radiography. The results were summarized as follows: 1. The percentage of density on concentrations of barium sulphate as contrast media could not show in differences with changes of voltages applied X-ray tube. 2. The changes of density visualized on X-ray film mainly depend upon with thickness of stomach filled barium sulphate than the ratio of barium sulphite and plain water volume. 3. The lesions positioned in upper part within stomach exhibited their best discrimination performanance with depth in the low tube voltage, followed in order by the middle part and lower part. However, the discrimination performanance at the high tension radiography uniformly visualized over X-ray film without density in change.

• 한국작물학회지
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• 제42권3호
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• pp.286-291
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• 1997

벼 담수토중직파시 산화제 종자분의에 의한 초기 출아입모 향상 효과를 시험한 결과를 요약하면 다음과 같다. 1. 산화환원전위차는 무처리가 가장 낮게 경과하였으며, KNO$_3$가 대체로 높으면서 산화 기간이 오래 지속되었던 반면 CaO$_2$는 타처리에 비해 약간 낮게 경과하는 경향이었고, 산화제처리로 출아기간동안 종자주위의 토양환원억제에 상당한 영향을 미쳤다. 2. 토양 pH변화는 무처리에서 7이상으로 가장 높게 경과하여 논토양의 환원된 상태를 보였으며, 산화제 처리구에서는 초기에 낮았다가 점차 높아지는 경향을 보였으나 무처리보다 낮아 일시적으로 토양을 산성화 시키는 효과를 보였다. 3. 입모수는 CaO$_2$가 파종후 8일경에 60%이상의 출아율을 보였고, 특이산성토 처리는 CaO$_2$ 보다는 낮았지만 무처리에 비해 입모율은 많이 향상되었다. 4. 초기생육에서 초장은 처리간 차이가 인정되지 않았고, 엽령차이는 CaO$_2$ 및 특이산성토에서 7.6매로 무처리의 6.2매에 비하여 1.4매 정도 많아 잎의 전개가 더 빨랐으며 근장 또한 CaO$_2$ 분의종자에서 10.2cm로 가장 길었고, 경수는 CaO$_2$와 특이산성토 피복종자에서 가장 많았다. 5. 본 실험에서 CaO$_2$는 입모가 균일하고 출아 소요 기간도 짧아 담수토중 직파재배에서 벼 종자 분의 재료로 가장 우수하였으며, 특이산성토분의에서도 양호하여 그 가능성을 검토할 수 있었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제10권2호
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• pp.107-117
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• 2005

Oral supplementation of minerals mixture of potassium bromide and nickel sulphate on $CSR_2,\;CSR_4\;and\;CSR_2{\times}CSR_4$ crossbreed races with different concentrations (70, 110 and $160\;{\mu}g/ml$) were fed to the fifth instar larvae. Two of the four normal feeds per day was substituted with treated leaves fed to silkworm at fifth instar larvae. The controls were fed with the leaves sprayed with distilled water and normal leaves. The $CSR_4$ race treated larvae showed a significant increase in silkgland weight, cocooning percentage, female cocoon weight, male cocoon weight, male cocoon shell weight, male cocoon shell ratio, filament length, filament weight, denier, fecundity, number of eggs per ovariole and length of the ovariole when compared with those of the corresponding parameters of the carrier control, whereas in $CSR_2\;and\;CSR_2{\times}CSR_4$ crossbreed races showed a significant increase in larva1 weight and other parameters similar to that of $CSR_4$ race. The results suggested that the silkgland showed good response to minerals mixture of potassium bromide and nickel sulphate only in $CSR_4$ race when compared with those of other two races of the silkworm, B. mori.

• 한국수산과학회지
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• 제11권2호
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• pp.55-64
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• 1978

The present investigations were carried out for the purpose of making clear the fundamental features of the seasonal variations in carrageenan content and its chemical composition. The samples, Chondrus ocellatus, were collected every month from the same locality on the coast of Haewundae from March, 1975 to February, 1976, and analyzed monthly to determine their carrageenan content, sulphate and 3,6-anhydro-D-galactose over a year period. En addition, some chemical characteristics were also tested on the fractions separated by the different concentrations of potassium chloride. In seasonal variation, the maximum carrageenan content occurred from summer through autumn, and the minimum in winter, especially in February. It is noted in the seasonal variations of the sulphate content of total carrageenan and three fractions that the maximums appreared in October and minimums in february. With seasonal variations of percent 3,6-anhydro-D-galactose of total carrageenan and three fractions, maximum values occur in June and minimum values in December. Seasonal variations in sulphate and 3,6-anhydro-D-galactose contents of the three fractions were on the whole similar in mode of variation, and there could be no substancial differences. Seeing seasonal variations in the sulphate and 3,6-anhydro-D-galactose contents of three fractions, carrageenan extracted from the algae gathered in spring shelved higher portion of fraction I than that gathered in autumn. In these respects, it seems that a more weakly gelling k-carrageenan exists in the spring than in the autumn.

• Advances in Traditional Medicine
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• 제4권2호
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• pp.87-90
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• 2004

The efficacy of Arque-Ajeeb (AA), a compound formulation of Unani medicine was investigated for antidiarrhoeal activity against barium sulphate-induced gut motility and castor oil-induced diarrhoea in rats. The control, standard and test groups of experimental animals were administered with distilled water (p.o.), lomotil (p.o.) and AA (0.007 ml and 0.014 ml/100 g, p.o.) respectively. Barium sulphate and castor oil were administered after 15 and 60 min respectively in each group of first and second experiment. The distance traveled by barium sulphate in small intestine was measured after 15 and 30 min of barium sulphate administration and diarrhoea was observed every 30-min for six hour after castor oil administration. Oral administration of AA caused significant reduction in diarrhoea. AA may have the potential to reduce the diarrhoea in rats.