• The Journal of Engineering Geology
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• v.32 no.1
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• pp.127-142
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• 2022

This study explored the fluid transfer characteristics of simultaneous pneumatic blasting, plasma blasting, and vacuum suction (the PPV method), and assessed their effect. Chemical oxidation-an established soil remediation method-was compared as a control. Electrical resistivity surveys found that PPV reduced resistivity by about 1.5-2.5 times compared with the control group, indicating that it increased the diffusion of fluid between the injection and suction wells. Injection and suction tests comparing the injection flow rate, initial suction flow rate time, and suction flow rate showed that the PPV method offered an improvement over the existing method. Slug tests revealed that PPV increased the permeability coefficient by a greater amount than that by the control method. This study qualitatively and quantitatively confirmed that the PPV method clearly improves injection and suction efficiency by accelerating cracks in the ground and improving water permeability compared with the established chemical oxidation method.

• 한국초전도학회:학술대회논문집
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• v.11
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• pp.43-43
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• 2001

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1416-1419
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• 2005

Design and manufacturing of plastic injection mold with cavity pressure/temperature sensors were performed in the present study for tensile test specimen. Standards of mold-base and tensile test specimen were used to design an injection molding system. Cavity pressure and temperature sensors were placed on the side of fixed platen of injection mold machine to prevent them from external impact damage. Injection molding experiments with variations of injection speed and melt temperature were performed and polycarbonate tensile specimens were prepared for the tensile test. It was shown that injection molding processing parameters can have effect on the mechanical properties of the plastic injection molded part.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2001.04a
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• pp.39-40
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• 2001

• Tunnel and Underground Space
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• v.23 no.1
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• pp.13-30
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• 2013

Increase of pore fluid pressure resulting from injection of $CO_2$ may reactivate pre-existing faults, and the induced seismic activities can raise the safety issues such as seal integrity, restoration of storage capacity, and, in the worst case, removal of previously injected $CO_2$. Thus, fault stability and potential for $CO_2$ leakage need to be assessed at the stage of site selection and planning of injection pressure, based on the results of large-scale site investigations and numerical modeling for various scenarios. In this report, studies on the assessment of fault stability during injection of $CO_2$ were reviewed. The seismic activities associated with an artificial injection of fluids or a release of naturally trapped high-pressure fluids were first examined, and then site investigation methods for the magnitude and orientation of in situ stresses, the distribution and change of pore fluid pressure, and the location of faults were generally summarized. Recent research cases on possibility estimation of fault reactivation, prediction of seismic magnitude, and modeling of $CO_2$ leakage through a reactivated fault were presented.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.1
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• pp.181-187
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• 2008

Recently, alternative fuels are drawing more attentions due to the increasing need for lower emission characteristics and fuel consumption rate in automotive engines. The GTL(gas to luquid) is the one of most favored candidates. It has higher cetane number(more than 75) and almost negligible sulphur and aromatic contents. Therefore, enhanced emission characteristics are expected even in the application in diesel engines without any modification. In this study, the cylinder pressure and heat release, emission characteristics with fuel injection timings are compared between diesel and GTL fuel in the single cylinder diesel engine. Noticeable reduction in PM, THC and CO emission are observed due to lower sulphur and aromatic contents in GTL. Also, the ignition delay decreased due to higher cetane number of GTL, which slightly decreased the amount of NOx emissions. With the retards of main injection timing, NOx decreases more for the case of GTL, while the level of THC and CO emissions still remains lower than the case of diesel. Therefore, there is much room for the control of injection timing for NOx reduction without sacrificing THC and CO emissions. With the retards of main injection timing, Small size distribution of PM became lager and there amount increased. But from all conditions, size distribution of PM for the case GTL was lower than Diesel.

• Journal of Environmental Health Sciences
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• v.31 no.1
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• pp.15-22
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• 2005

This study was conducted to evaluate air injection mode on stabilization of solid waste in lysimeter. For three lysimeters, one was maintained under anaerobic condition as control, and air was injected into two lysimeters in continuous mode (atmospheric pressure) and intermittent mode (high pressure of 2 bar). Distilled water was sprayed over solid waste in 1.4 l/$m^3$(solid waste)/day, supposing rainfall intensity of 1,200 mm/yr and 30% infiltration. Oxygen in landfill gas was not detected in control lysimeter during operational days. After 30 day-aeration, oxygen concentrations of continuous and intermittent modes were maintained in 14% and 6%, respectively. $COD_{Cr}$ removal efficiencies of continuous and intermittent modes were about 70% and 50%, and BOD5 removal efficiencies were about 80% and 20%, respectively. In view of oxygen supply, and $COD_{Cr}$ and $BOD_5$ removal, continuous air injection mode of atmospheric pressure was more effective than intermittent mode of 2 bar. Settling degree of solid waste in case of two air injection modes was 3 times higher than that of anaerobic condition as control. Considering the above results, it was thought that air injection (especially continuous atmospheric pressure) could improve degradation of solid waste and induce preliminary stabilization in landfill site.

• Archives of Pharmacal Research
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• v.25 no.3
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• pp.357-363
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• 2002

The effect of a new rhFSH, PG-0801, on oocyte quality, ovulation and in vitro fertilization (IVF) was examined in androgen-sterilized mice. Experimental sterility was induced by a single subcutaneous injection of testosterone propionate (TP, 1 mg/head) into 5 day old female mice. Ovulation was generated in the 10 to 13-week old TP-injected mice by a subcutaneous rhFSH injection (1, 5 or 10 IU/head) followed 48 hours later by a second rhFSH injection (1, 5 or 10 IU/head). For comparison, a subcutaneous PMSG (5 IU/head) injection was used for folliculogenesis and a hCG (5 IU/head) injection was used for ovulation. These were administered using the same protocol. The eggs were harvested from the oviducts and counted 17 to 20 hours after the second injection. IVF was performed by adding sperms ($2{\times}10^{5}/ml{\;}to{\;}2{\times}10^{6}/ml$) to determine the functional activity of the eggs, and the fertilization rate was measured. In addition, the pregnancy rate and fetal development were examined after 15-17 days of gestation. The number of oocytes recovered from the rhFSH/rhFSH group increased dose-dependently and was slightly higher than that of the PMSG/hCG group. The pregnancy rates of the group receiving 1, 5, and 10 IU of rhFSH/rhFSH were 50%, 66.7%, and 75%, respectively, which were significantly higher than that of the control (untreated) group (0%). The numbers of viable fetuses in the 1, 5, and 10 IU/head of the rhFSH/rhFSH group ($8.0{\pm}1.50$, $8.9{\pm}1.02$, and $8.9{\pm}1.12$ fetuses/dam, respectively) were comparable to that of the 5 IU/head PMSG/hCG group ($9.4{\pm}0.94$). The mice receiving rhFSH/rhFSH and PMSG/hCG showed similar fertilization rates (around 65%) via the IVF procedure. These results demonstrate that a new rhFSH, PG-0801, may be useful for inducing ovulation in functionally infertile patients and for superovulation in ovulatory patients participating in assisted reproductive technology (ART) programs.

• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.367-375
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• 2016

A novel strategy for the synthesis of $CoSb_2$ nanoparticles is demonstrated via preparation of novel organometallic complexes. Hydrated cobalt oleate (CoOl) and non-hydrated antimony oleate (SbOl) complexes are synthesized as precursors. The $CoSb_2$ nanoparticles are prepared by hot injection, which involves thermolysis of CoOl and SbOl in a non-coordinating solvent at $320^{\circ}C$. The coordination modes and distinct thermal behaviors of the intermediate non-hydrated SbOl complexes are comparatively investigated by thermo-analytical techniques. When the reaction temperature is increased, the particle size is found to increase linearly. The crystallinity of the $CoSb_2$ nanoparticles prepared at $250^{\circ}C$ is amorphous phase without any peaks. $CoSb_2$ structural peaks start to appear at $300^{\circ}C$ and dominant peaks with high crystallinity are synthesized at $320^{\circ}C$. The potential chemical structures of non-hydrated SbOl and their reaction mechanisms by thermolysis are elucidated. The elemental composition and crystallographic structure of $CoSb_2$ nanoparticles suggest a bimodal interaction of the organic shell and the nanoparticle surface, with a chemical absorbed inner layer and physically absorbed outer layer of carboxylic acid.

• Geophysics and Geophysical Exploration
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• v.9 no.1
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• pp.30-36
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• 2006

Japan's first pilot-scale $CO_2$ sequestration experiment has been conducted in Nagaoka, where 10400 t of $CO_2$ have been injected in an onshore aquifer at a depth of about 1100 m. Among various measurements conducted at the site for monitoring the injected $CO_2$, we conducted time-lapse crosswell seismic tomography between two observation wells to determine the distribution of $CO_2$ in the aquifer by the change of P-wave velocities. This paper reports the results of the crosswell seismic tomography conducted at the site. The crosswell seismic tomography measurements were carried out three times; once before the injection as a baseline survey, and twice during the injection as monitoring surveys. The velocity tomograms resulting from the monitoring surveys were compared to the baseline survey tomogram, and velocity difference tomograms were generated. The velocity difference tomograms showed that velocity had decreased in a part of the aquifer around the injection well, where the injected $CO_2$ was supposed to be distributed. We also found that the area in which velocity had decreased was expanding in the formation up-dip direction, as increasing amounts of $CO_2$ were injected. The maximum velocity reductions observed were 3.0% after 3200 t of $CO_2$ had been injected, and 3.5% after injection of 6200 t of $CO_2$. Although seismic tomography could map the area of velocity decrease due to $CO_2$ injection, we observed some contradictions with the results of time-lapse sonic logging, and with the geological condition of the cap rock. To investigate these contradictions, we conducted numerical experiments simulating the test site. As a result, we found that part of the velocity distribution displayed in the tomograms was affected by artefacts or ghosts caused by the source-receiver geometry for the crosswell tomography in this particular site. The maximum velocity decrease obtained by tomography (3.5%) was much smaller than that observed by sonic logging (more than 20%). The numerical experiment results showed that only 5.5% velocity reduction might be observed, although the model was given a 20% velocity reduction zone. Judging from this result, the actual velocity reduction can be more than 3.5%, the value we obtained from the field data reconstruction. Further studies are needed to obtain more accurate velocity values that are comparable to those obtained by sonic logging.