• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1239-1243
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• 1999

The optimal medium composition for the production of carotenoid pigment from Haloarcular sp. EH 1 as a dietary for fishes were 1.0% sucrose, 1.0% yeast extract, 25% sodium chloride, 0.3% sodium citrate, 0.2% potassium chloride, 2.0% magnesium sulphate, 0.002% ferric sulphate(pH 7.0). The incubation temperate, aeration rate and agitation speed were 40oC, 100ml medium/500ml vol. shaking flask, and 180 rpm/min. The carotenoid pigment production was highest after 5 days of incubation with the light.

• Nuclear Engineering and Technology
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• v.29 no.3
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• pp.260-268
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• 1997

The effects of three mechanisms, calcium depletion, sulphate and carbonate penetration, on the concrete degradation have been studied. The shrinking core model (SCM) and the HYDROGEOC. HEM (HGC) model have been applied to evaluate how fast the mechanisms proceed. The SCM is an analytical approximation model and the HGC is a numerical mass transport model coupled with chemical reaction. The SCM leads to more conservative results than the HGC, and turns out to be very useful in the viewpoint of simplicity and conservatism. During 300 years, calcium has been depleted within 10 cm from the concrete outer surface, and sulphate has penetrated less than 13.5 cm into the concrete. Carbonate has not penetrated own 7 cm into the concrete in contact with the bentonite, and, furthermore, its penetration into the concrete with the groundwater is negligible. Conclusively, the concrete is expected to maintain its integrity for at least 300 years that are regarded as institutional control period of intermediate and low-level radioactive waste repository.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2887-2889
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• 2009

An efficient and easy method for one-pot three-component synthesis of amidoalkyl naphthols by the condensation of aromatic/heteroaromatic/aliphatic aldehydes, 2-naphthol and amides or urea under thermal condition at $60^{\circ}C$ in the presence of acidic ionic liquid 1-butyl-3-methylimidazolium hydrogen sulphate ([bmim]$HSO_4$) has been described.

• The Korean Journal of Pain
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• v.24 no.1
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• pp.53-56
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• 2011

Although postherpetic neuralgia (PHN) is a common chronic pain syndrome, the pathophysiology of this disorder is not well known and management is often very difficult. N-methyl-D-Aspartate (NMDA) receptor antagonists are known to be effective in PHN, and magnesium, a physiological blocker of NMDA receptors, is widely used to treat various chronic pain disorders. Here, we present a case of the PHN refractory to conventional treatment, which was treated successfully with transforaminal epidural injection of magnesium sulphate at the affected dermatome.

• Journal of the Korean institute of surface engineering
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• v.22 no.4
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• pp.161-167
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• 1989

Effects of bath composition on electroless deposition of Ni-W-B from sulphate solution were invesrigated in terms of deposition kinetics, electro resistivity and composition of deposit film. The microstruigated and crystataine structure of the films were also studied using a scanning electron microscope and X-ray diffractometer. The deposition rate increased linearly with increasing the concentration of nickel sulphate in bath solution, wheras the rate decreasing with sodium citrate. The rate was also affected by sodium tungstate, which was maaximum at the concentration of 0.06 M/1 in sodium tungstate, The content of W in the deposit increased with increased with increasing the sodium citrate had on opposite effect on the composition of W and B in the deposit. The crystal change film from armorphous to cryatallicne nature by heat treatments was proved by the reduction of specific resistance and X-ray diffration.

• Advances in concrete construction
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• v.8 no.3
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• pp.199-206
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• 2019

High performance sandcretes (HPS) are new concretes characterized by particles having a diameter less than 5 mm, as well as very high mechanical strength and durability. This work consists in finding solutions to make sandcretes with good physico-mechanical and durability properties for this new generation of micro-concrete. However, upgrading ordinary sandcrete into high performance sandcrete (HPS) requires a thorough study of formulation parameters (equivalent water/binder ratio, type of cement and its dosage, kind and amount of super plasticizer, and gravel/sand ratio). This research study concerns the formulation, characterization and durability, in a sulphate environment, of a high performance sandcrete (HPS), made from local materials. The obtained results show that the rheological properties of fresh concrete and mechanical strength differ with the mineralogy, density and grain size distribution of sands and silica fume used.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.86-86
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• 1998

• Advances in concrete construction
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• v.9 no.3
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• pp.267-278
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• 2020

This paper reports on the result of an experimental investigation carried out to study the compressive strength and sorptivity properties of blended cement concrete exposed to 5% and 10% MgSO₄ solution using fly ash (FA) and silpozz. Usually in sulphate environment the minimum grade of concrete is M30 and the mix design is done for target mean strength of 39 MPa. Silpozz is manufactured by burning of agro-waste rice husk in designed furnace in between 600° to 700℃ which is one of the main agricultural residues obtained from the outer covering of rice grains during the milling process. There are four mix series taken with control mix. The control mix made 0% replacement of FA and silpozz with Ordinary Portland Cement (OPC). The first mix series made 0% FA and 10-30% replacement of silpozz with OPC. The second mix series made with 10% FA and 10-40% replacement of silpozz with OPC. The third mix series made 20% FA and 10-30% replacement of silpozz with OPC and the fourth mix series made 30% FA and 10-20% silpozz replaced with OPC. The samples (cubes) are prepared and cured in normal water and 5% and 10% MgSO₄ solution for 7, 28 and 90 days. The studied parameters are compressive strength and strength deterioration factor (SDF) for 7, 28 and 90 days. The water absorption and sorptivity tests have been done after 28 days of normal water and magnesium sulphate solution curing. The investigation reflects that the blended cement concrete incorporating FA and silpozz showing better resistance against MgSO₄ solution when compared to normal water curing (NWC) samples.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.4
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• pp.293-296
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• 1990

The effect of wallastonite, potassium chloride and potassium sulphate on the ammonification and nitrification of urea was studied in a non-planted green house experiment, filling with 500g soil in plastic pot and incubating for 17 days. Potassium sulphate gave superior effect on the neutralizing soil acidity of wallastonite than potassium chloride and raised soil pH which promoted ammonification and subsequent nitrification of urea. Less than 20% $NO_3-N$ against the sum of $NH_4-N$ and $NO_3-N$ was accumulated in soils incubated bellow pH 6.0. It seemed that pH 5.2 to 6.0 was the critical range for the nitrification of ammonium, or raising the concentration of ammonia in soils to the toxic level to the nitrification. It appeared that the nitrification could be occuring in low moisture, air dried, conditions of soil.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.2
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• pp.117-124
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• 2014

The interest in the use of shield TBM (Tunnel Boring Machine) on the tunnel excavation has been increased rapidly in Korea. The shield TBM tunnel is generally designed as non-drainage tunnel. Consequently, if water leakage through the segment joints happens, big problems on the usage and stability of tunnel can be occurred. In this study, the variation of waterproof capacity of hydrophilic waterstop by the construction error and excessive displacement of segment was studied firstly. Secondly, the decrease of durability of hydrophilic waterstop by the sulphate and chloride contained in the groundwater and seawater was investigated. The results showed that if the angle discordance at the segment joints is beyond the 2 degree, the proper waterproof capacity of hydrophilic waterstop can not be guaranteed. In addition, if the hydrophilic rubber waterstop is exposed to the sulphate for a while, the proper durability of hydrophilic waterstop can not be expected.