• Clean Technology
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• v.13 no.1 s.36
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• pp.1-15
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• 2007

Biological treatment is a relatively recent air pollution control technology in which off-gases containing biodegradable odors and volatile organic compounds(VOCs) are vented through microbes. It is a promising alternative to conventional air pollution control methods. Bioreactors for air pollution control have found most of their success in the treatment of dilute and high flow waste air streams containing VOCs and odor compounds. They offer several advantages over traditional technologies such as incineration or adsorption. These include lower treatment costs, absence of formation of secondary pollutants, no spent chemicals, low energy demand and low temperature treatment. The three most widely used technologies are described, namely biofiltration, biotrickling filtration, bioscrubbing. The most widely used bioreactor for air pollution control is biofilter, but it has several limitations. In the past years major progress has been accomplished in the development of vapor phase bioreaction systems, for solving problems of biofilter. Biotrickling filters are more complex than biofilters, but are usually more effective, especially for the treatment of compounds which are difficult to degrade or compounds that generate acidic by-products. This, paper reviews fundamental and theoretical/practical aspect of air pollution control in biofilter, biotrickling filter and bioscrubber, focusing more extensively on biotrickling filtration. Special emphasis is given to the operating parameters and the factors influencing performance for air pollution control, and cost estimation in biotreatment technologies.

• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.265-270
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• 2004

To select a promising technologies for removal of odorous gases emitted from a wastewater pump station, four methods such as activated carbon (A/C) adsorption, chemical absorption (acid and alkali scrubber), and two biofilters (polyurethane (PU) and worm cast) were investigated. The average odor removal efficiencies in the PU biofilter and A/C column was over 98%, but in a worm cast biofilter and chemical absorption were below 60-80%. The removal efficiency of PU biofilter was very stable (about 98-99%) in the range of retention times of 4-36s, and a maximum elimination capacity was $1.6${\times}$10^{ 7}$ $OUm^{-3}$$h^{-1}$ Deodorization costs for an activated carbon adsorption and a biofiltration method were investigated. With increasing odor intensity, the operating cost of the A/C column increased linearly, but the operating cost of the biofilteration increased slightly. The capital cost in a biofilter is about two times higher than that in an A/C column, but the operating cost is very lower than that of in A/C column. In conclusion, the biofiltration was evaluated one of the most promising technologies to control odor in a wastewater pump station.

• Journal of Korea Soil Environment Society
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• v.1 no.2
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• pp.3-13
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• 1996

The efficiency of bioremedation can be measured by the enumeration of microorganism, respiration rate and decomposition rate. The side-effect can be measured by using Daphnia, oyster larvae and rainbow trout. Oxygen transfer could be a problem in the on-site treatment. For these, hydrogen peroxide can be used for solvents such as benzenes. Oleophilic nitrogen and phosphorus can be added for the treatment of oil pollution. Mixed microbial population or pure culture can be used for the inoculum. The pure culture used is Pseudomonas and Phanerochate. Sometimes enzymes are added and Photodegadation is coupled to increase the efficiency. For the treatment of oil pollution residue on soil such as waste lubrication oil and machine oil sludges, top soil of 15cm∼20cm depth is plowed and oil residue with approximately 5% concentration is applied. The optimum pH range is 7∼8, the ratio of phosphorus to hydrocarbon is 1:800. Appropriate drainage is necessary. For the treatment of marine oil pollution residue, addition of oleophilic fertilizer is effective. Air pollutiant such as oder can be treated by bioremediation. In this case, biofilters or biosrubbers are used for the reactor.

• The Korean Journal of Zoology
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• v.32 no.3
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• pp.264-274
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• 1989

In order to study the influence of spermatozoa and testicular fluid on the component and composition of proteins in epididymal fluid of mice, histological differentiation of testis and epididymis were observed during sexual maturation, and the proteins in epididymal fluids collected according to the characteristics of lumination were analyzed by electrophoresis (SDS-PAGE). In 10 day-old mouse, both of,testis and epididymis were undifferentiated. In 20 day-old mouse, epididymis was primitively luminated, but testis was not. In 35 day-old mouse, both of testis and epididymis were luminated and eaithdymal epithelium was differentiated into principal cells and clear cells. Spermatozoa were not transfered into epididymis yet. However, in 80 day-old mouse, both of festis and epididymis were fully differentiated and spermatozoa were transfered into epididymis. In electrophoretic paftem of proteins in epididymal fluid, a total of 28 kinds of proteins were identified, which were different from those of their sera. 12 kinds out of these proteins were epididymal specific protein(ESP) detected in epididymal fluid only, and the other 16 kinds(TEP) were also detected in testicular fluid. The proteins in epididymal fluid changed during sexual maturation and 3 kinds of the proteins changed quantitatively according to epididymal regions in adult. It may be concluded from the above results that the component and composition of the proteins in epididymal fluid changed by the influx of testicular fluid including spermatozoa into epididymis and regulation of the protein synthesis, secretion and/or absorption by the epididymal epithelium. Therefore it is strongly suggested that ESP and TEP in epididymal fluid play somehow significant roles on the maturation of epididymal spermatozoa.

• Journal of Conservation Science
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• v.33 no.1
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• pp.25-33
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• 2017

The stone lantern of the four guardian kings in the Beopjusa temple at Boeun was mainly made of biotite granodiorite consisting of porphyritic-textured potassium feldspar and included in ilmenite series. A base stone made of alkali granite was buried, after founded its place during an earlier restoration process. Cracking and break out are noticeable on this object. In addition, discoloration, salt crusting, and epiphytes were observed. The lantern was vulnerable in terms of physical and structural stability caused by cracking in the front and back of the light chamber and in the non-horizontal direction. According to the conservational condition of the stone lantern, structural reinforcement was carried out based on calculations, including those on the position, size, and anchor length of the titanium stiffener. Chemical and biological pollutants were washed off without damage to the surface of the stone material. Oxygenated iron pieces were replaced with titanium. Ethyl silicate was applied to the surface of the lantern for consolidation and smooth drainage.

• Development and Reproduction
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• v.14 no.4
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• pp.281-286
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• 2010

Recent evidence has revealed that the intratesticular injection of hypertonic saline(20%) resulted in a chemically castrated state such as nadir testosterone levels in rats. To confirm the efficacy of this simple saline-injection method further, we investigated the changes in the gross and microscopic anatomy of testis. Our study comprised three groups; intact(control) group, orchidectomy group and saline-injection (experimental) group. Single dose of hypertonic saline (sterilized, $750{\mu}{\ell}/testis$) were directly administered into both testis of adult rats (about 300 g BW). Bilateral orchidectomy was performed at the same day of saline injection. Following 30 days post-injection, reproductive tissues were surgically removed, weighed and fixed for histological examination. The body weights were not changed in both orchidectomy group and saline-injection group when compared to those in intact group. The wet weights of testis were significantly decreased in saline-injection group when compared to those in intact group. The wet weights of epididymis and seminal vesicle and prostate were significantly decreased in orchidectomy group and saline-injection group when compared to those in intact group. Macroscopically, the testes exerted slight atrophy and the tunica albuginea seemed to be intact in saline injection group. Histologically, however, larger parts of testicular tissue underwent necrosis and were barely recognizable after hematoxylin-eosin staining. In the same section, only the opposite part of the injection site was stained showing abnormal state of cell layers mostly fibrosis and infiltrated leukocytes. Sloughing of immature germ cells from the basement membrane along with shedding cells in the intraluminal space was notable in most seminiferous tubules from the saline injected testis. The present study confirmed that the direct injection of hypertonic saline into testis can induce a castration-like, testosterone-depriving effects on accessory sex organs. Our findings suggest that the efficacy of this less expensive and minimally invasive method seems to be almost even with that of conventional orchidectomy and chemical castration, though more in-depth evaluation should be supported.

• Journal of Chest Surgery
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• v.41 no.6
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• pp.679-686
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• 2008

Background: Cellular remnants in the bioprosthetic heart valve are known to be related to a host's immunologic response and they can form the nidus for calcification. The extracellular matrix of the decellularized valve tissue can also be used as a biological scaffold for cell attachment, endothelialization and tissue reconstitution. Thus, decellularization is the most important part in making a bioprosthetic valve and biological caffold. Many protocols and agents have been suggested for decellularization, yet there ave been few reports about the effect of a treatment with hypotonic solution prior to chemical or enzymatic treatment. This study investigated the effect of a treatment with hypotonic solution and the appropriate environments such as temperature, the treatment duration and the concentration of sodium dodecylsulfate (SDS) for achieving proper decellularization. Material and Method: Porcine aortic valves were decellularized with odium dodecylsulfate at various concentrations (0.25%, 0.5%), time durations (6, 12, 24 hours) and temperatures ($4^{\circ}C$, $20^{\circ}C$)(Group B). Same the number of porcine aortic valves (group A) was treated with hypotonic solution prior to SDS treatment at the same conditions. The duration of exposure to the hypotonic solution was 4, 7 and 14 hours and he temperature was $4^{\circ}C$ and $20^{\circ}C$, respectively. The degree of decellularization was analyzed by performing hematoxylin and eosin staining. Result: There were no differences in the degree of decellularization between the two concentrations (0.25% 0.5%) of SDS. Twenty four hours treatment with SDS revealed the best decellularization effect for both roups A and B at the temperature of $4^{\circ}C$, but there was no differences between the roups at $20^{\circ}C$. Treatment with hypotonic solution (group A) showed a better ecellularization effect at all the matched conditions. Fourteen hours treatment at $4^{\circ}C$ ith ypotonic solution prior to 80S treatment revealed the best decellularization effect. The treatment with hypotonic solution at $20^{\circ}C$ revealed a good decellularization effect, but his showed significant extracellular matrix destruction. Conclusion: The exposure of porcine heart valves to hypotonic solution prior to SDS treatment is highly effective for achieving decellularization. Osmotic treatment with hypotonic solution should be considered or achieving decellularization of porcine aortic valves. Further study should be carried out to see whether the treatment with hypotonic solution could reduce the exposure duration and concentration of chemical detergents, and also to evaluate how the structure of the extracellular matrix of the porcine valve is affected by the exposure to hypotonic solution.