• Applied Biological Chemistry
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• v.40 no.5
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• pp.409-415
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• 1997

In order to find out the relationship between contained water and coloring rate of thiamine monosalts in preparations, three kinds of thiamine monorhodanate, -monoiodide, -monobromide were manufactured and investigated as powders, granules and compressed tablets, respectively. Apparent coloring rate constants and solubility in accordance with temperature changes were measured. Nature of contained water and coloration of thiamine monosalts in preparations was examined in detail. It was thereby found that if water attached in a free state, coloration occured whose degree was approximately proportional to the quantity of such water, and a linear relation was found to hold between the logarithm of the apparent coloring rate constants and the reciprocal of the absolute temperature in granules and compressed tablets.

• Journal of the Korean Chemical Society
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• v.28 no.3
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• pp.194-202
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• 1984

The adsorption properties of organo sulfur compounds on cation exchanged natural zeolites from n-heptane were investigated. The equilibrium adsorbed amounts were dependent upon the exchanged cation and the nature of organo sulfur compounds such as length, volume, electronical structure. The increasing orders of equilibrium adsorbed amounts were thiophene derivatives, disulfide, sulfide mercaptane and thiophene, benzothiaphene, dibenzothiophene. And $Co^{+2}$-zeolite was the most prominent adsorbant. Rate determining step of the adsorption at initial stage was intraparticle diffusion into the transitional pores of zeolite. These adsorption rates were dependent upon the bulkiness of adsorbate. Finally, preadsorbed water didn't affect these adsorption until the cation exchanged natural zeolite contained 2.26${\times}10^{-3}$ mol/g of water. It indicated that water preferentially occupied the micro pores of the cation exchanged natural zeolites.

• Advances in concrete construction
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• v.9 no.5
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• pp.449-457
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• 2020

The influence of subsequent curing on the performance of fly ash contained mortar under steam curing was studied. Mortar samples incorporated with different content (0%, 20%, 50% and 70%) of Class F fly ash under five typical subsequent curing conditions, including standard curing (ZS), water curing(ZW) under 25℃, oven-dry curing (ZD) under 60℃, frozen curing (ZF) under -10℃, and nature curing (ZN) exposed to outdoor environment were implemented. The unsteady chloride diffusion coefficient was measured by rapid chloride migration test (RCM) to analyze the influence of subsequent curing condition on the resistance to chloride penetration of fly ash contained mortar under steam curing. The compressive strength was measured to analyze the mechanical properties. Furthermore, the open porosity, mercury intrusion porosimetry (MIP), x-ray diffraction (XRD) and thermogravimetric analysis (TGA) were examined to investigate the pore characteristics and phase composition of mortar. The results indicate that the resistance to chloride ingress and compressive strength of steam-cured mortar decline with the increase of fly ash incorporated, regardless of the subsequent curing condition. Compared to ZS, ZD and ZF lead to poor resistance to chloride penetration, while ZW and ZN show better performance. Interestingly, under different fly ash contents, the declining order of compressive strength remains ZS>ZW>ZN>ZD>ZF. When the fly ash content is blow 50%, the open porosity grows with increase of fly ash, regardless of the curing conditions are diverse. However, if the replacement amount of fly ash exceeds a certain high proportion (70%), the value of open porosity tends to decrease. Moreover, the main phase composition of the mortar hydration products is similar under different curing conditions, but the declining order of the C-S-H gels and ettringite content is ZS>ZD>ZF. The addition of fly ash could increase the amount of harmless pores at early age.

• Journal of Microbiology and Biotechnology
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• v.1 no.3
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• pp.212-219
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• 1991

Four species of yeast, Saccharomyces cerevisiae, Candida utilis, Saccharomycopsis flbuligera, and Schwanniomyces castellii were evaluated for their ability to bioconvert potato processing waste water into microbial protein and the resulting single-cell proteins were evaluated as protein sources for rainbow trout, using in vitro analyses. The studies indicated that Schwanniomyces castellii, which utilizes starch dircetly and converts it into cell mass efficiently, was suitable for the bioconversion. In the single-stage continuous bioconversion, the yield S. castellii cell mass, which contained approximately 37% protein, was 77%, at dilution rate 0.25 $h^{-1}$. Reduction of total carbohydrate was 81%. During batch fermentations, cell mass yield was about 72% and total carbohydrate reduction was 81%. Among the yeasts tested, S. castellii possessed the most fragile cell wall and had a favorable amino acid profile for salmonid fish; protein score of 86% (Met). In an in vitro pepsin digestibility test 80% digestibility (23~38% above control) was observed when cells were pre-heated in a steam bath for 30 min. Results presented should be regarded as being preliminary in nature because they were derived from single experiments.

• Ecology and Resilient Infrastructure
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• v.7 no.3
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• pp.189-198
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• 2020

Wetlands, which provide various ecological services, have been regarded as an important nature-based solution for, for example, sustainable water quality improvement and buffering of impacts from climate change. Although the importance of conserving wetlands to reduce the impacts of various perturbations (e.g., changes of land use, climate, and hydrology) has been acknowledged, the possibility of applying these efforts as a nature-based solution in a macro-scale (e.g., landscape) has been insufficient. In this study, we examine the possibility of ecological network analysis that provides an engineering solution as a nature-based solution. Specifically, we analyzed how land use change affects the structural and functional characteristics (connectivity, network efficiency, and clustering coefficient) of the ecological networks by using the ecological networks generated by multiple dispersal models of the hypothetical inhabiting species in wetlandscape. Changes in ecological network characteristics were analyzed through simultaneously removing wetlands, with two initial conditions for surface area, in the zones where land use change occurs. We set a total number of four zones of land use change with different wetland densities. All analyses showed that mean degree and network efficiency were significantly reduced when wetlands in the zones with high wetland density were removed, and this phenomenon was intensified especially when zones contained hubs (nodes with high degree). On the other hand, we observed the clustering coefficient to increase. We suggest our approach for assessing the impacts of land use change on ecological networks, and with additional analysis on betweenness centrality, we expect it can provide a nature-based engineering solution for creating alternative wetlands.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.11-30
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• 2000

Structural properties of reinforced concrete, such as bond and shear strength, that depend on the tensile properties of concrete are much lower for high-strength concrete than would be expected based on relationships developed for normal-strength concretes. To determine the reason for this behavior, studies at the University of Kansas have addressed the effects of aggregate type, water-cementitious material ratio, and age on the mechanical and fracture properties of normal and high-strength concretes. The relationships between compressive strength, flexural strength, and fracture properties were studied. At the time of test, concrete ranged in age from 5 to 180 days. Water-cementitious material ratios ranged from 0.24 to 0.50, producing compressive strengths between 20 MPa(2, 920 psi) and 99 MPa(14, 320psi). Mixes contained either basalt or crushed limestone aggregate, with maximum sizes of 12mm(1/2in). or 19mm(3/4in). The tests demonstrate that the higher quality basalt coarse aggregate provides higher strengths in compression than limestone only for the high-strength concrete, but measurably higher strengths in flexure, and significantly higher fracture energies than the limestone coarse aggregate at all water-cementitious material ratios and ages. Compressive strength, water-cementitious material ratio, and age have no apparent relationship with fracture energy, which is principally governed by coarse aggregate properties. The peak bending stress in the fracture test is linearly related to flexural strength. Overall, as concrete strength increases, the amount of energy stored in the material at the peak tensile load increases, but the ability of the material to dissipate energy remains nearly constant. This suggests that, as higher strength cementitious materials are placed in service, the probability of nonductile failures will measurably increase. Both research and educational effort will be needed to develop strategies to limit the probability of brittle failures and inform the design community of the nature of the problems associated with high-strength concrete.

• Journal of Microbiology
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• v.34 no.4
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• pp.320-326
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• 1996

To analyze the effects of host versus plasmid on survival of 2, 4-degrading bacteria in environmental samples, strains Pseudomonas cepacia/pJP4, Alcaligenes JMP228/pJP4, P. cepacia/p712, and Alcaligenes JMP228/p712 were separately inoculated into samples of field soil, paddy soil, lake water, and river water, and then the changes of their populations were measured. The strains used contained a 2, 4-D degradative plasmid, either pJP4 conferring fast-growing property to the host or p712 conferring slow-growing property, and were resistant to antibiotics such that the inoculated strains could be enumerated against the indigenous microbial populations. In sterile environmental samples, these strains were stably maintained at the levels used for inoculation, except in sterile paddy soil where Alcaligenes JMP228 strains died drapidly. In natural soil samples for four strains declined steadily with time, but in naturla water samples their polulations fell rapidly at the early phase and then remained almost constant. When the environmentla samples were treated with 2, 4-D, P. cepacia/pJP4 and P. cepacia/p712 maintained significant numbers, while Alcaligenes JMP228/pJP4 and Alcaligenes JMP228/p712 declined significantly in most of the samples. The results indicated that the survivability of genetically modified microorganisms could vary depending on the environments and that their abundance in the environments under s2, 4-D selection was markedly influenced by the nature of the 2, 4-D degradative plasmid as well as type of the host strain.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.102-102
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• 2019

Soybean curd residue (SCR), known as a major waste product of soybean processing, is the water-insoluble fraction which is removed by filtration during soymilk production. For these reasons, SCR was usually considered as food waste. SCR might have a good potential as a functional food material, value-added processing and utilization. SCR contains high-quality protein and consists of a good source of nutrients, including protein, oil, dietary fiber, minerals, along with un-specified monosaccharides and oligosaccharides. Also, SCR might be a potential source of low cost protein for human consumption. However, SCR could be a source of bacterial contamination when during food processing. This study was aimed to investigate antibacterial capacity of natural product through detecting relationship between SCR and microbial. We isolated five bacterial strains from SCR and elucidated antibacterial activity of nature medicines to extend storage capacity of food made with SCR. Thus, the extract which showed antibacterial effects in Corynebacterium calloonae and Raoultella amithinolytica is a combination of seven kinds of extracts: Glycyrrhiza uralensis, Cudrania tricuspidata, Salvia miltiorrhiza Bunge, blueberry, Acorus gramineus, Ginkgo biloba L., Camellia sinensis. This study suggested that antibacterial activities of natural medicines could be used for extension of storage capacity in SCR-contained food.

• BMB Reports
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• v.30 no.1
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• pp.37-40
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• 1997

Earthworm extracts are known for anti-inflammatory, analgesic. antipyretic, and anticancer effects but can also influence blood circulation. It was previously shown that an earthworm, Lumbricus rubelius. contained a water-extractable anticoagulant which was a heat- and acid-stable molecule with hydrophilic property. In order to uncover the biochemical nature of this molecule, the anticoagulant was processed with various hydrolases such as trypsin, DNase, RNase. and lysozome. When the digested samples were analyzed with an in vitro coagulation test measuring activated partial thromboplastin time (APTT) and agarose gel electrophoresis, the anticoagulant proved to be a relatively homogeneous DNA fragment with relative molecular size around 72 base pairs. Interestingly, the activity was further stimulated with a trypsin digestion. RNA. on the other hand, did not prolong the APTT. It was also demonstrated that the DNA accelerated the antithrombin III (AT-III) inhibition of thrombin from $IC_{50}$ of 0.34 to 0.16 unit determined with S-2238 as a substrate, whereas heparin, a popular anticoagulant. shifted the value to 0.05. Therefore, it is suggested that the DNA could be considered as an alternative antithrombotic agent to heparin, which would exhibits bleeding side effects.

• Nutritional Sciences
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• v.9 no.3
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• pp.190-194
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• 2006

Silajit is a blackish brown pitch-like gummy substance. It is an important Unani and Ayurvedic medicine widely used in the treatment of many diseases and as nutritional supplement It is found in certain mountainous regions of Pakistan, Afghanistan, India, Nepal, Australia and Russia. Silajit samples of Pakistani origin were obtained from different sources and analyzed for their physical characteristics and biochemical & elemental composition. X-ray diffraction studies on Silajit showed that it is an amorphous substance and has no crystalline structure. Also, pH studies of Silajit (2 g/L of water) indicated that it was slightly acidic in nature and ranged from 3.45 to 7.23. Conductivity ranged from 157.7 to 330. Amino acid analysis revealed that Silajit contained lysine and alanine in higher amounts than all other amino acids and ranged from 1456 to 2240 and 68 to $1615{\eta}mole/g$, respectively. Mean concentration of arsenic, mercury, cadmium, lead, copper and zinc was 73.15, 104.92, 0.496, 3.89, 4.04 and 17.23 ppm, respectively. Silajit samples were also analyzed for calcium, potassium and sodium.