• Journal of Korean Society of Water and Wastewater
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• v.26 no.2
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• pp.275-283
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• 2012

MCM-41(Mobil's Composition of Matter-41) and expanded graphite(EG) were investigated as potential adsorbents for heavy metal ions including Pb(II), Cu(II) and Ni(II) in various aqueous chemistries. MCM-41 showed shorter equilibrium times and higher adsorption capacities for all three heavy metal ions compared to expanded graphite. The adsorption of three heavy metal ions was significantly affected by the solution pH due to the competition with $H_{3}O^{+}$ at lower pH and precipitation at neutral or higher pH. Adsorptions of heavy metal ions onto MCM-41 and expanded graphite were successfully described with the pseudo-second-order model. During the competitive adsorption of three heavy metal ions, the selectivity of Pb(II) was highest and almost same selectivity was observed with Cu(II) and Ni(II) when MCM-41 was used as an adsorbent, while the expanded graphite exhibited the highest selectivity to Pb(II), followed by Ni(II) and Cu(II).

• Applied Chemistry for Engineering
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• v.19 no.2
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• pp.242-248
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• 2008

The iron incorporation method according to addition steps during the synthesis of iron incorporated MCM-41 was examined systematically. Iron addition during pH adjustment was more effective than the other addition steps which were addition to template agent solution or addition after mixing of template agent and sodium silicate solution. In case of iron addition after extraction of template agent from as-synthesized silica MCM-41, most of the iron was on the surface of pores not the frame work structure. Although the amount of iron addition was increased, there was a limit to the amount of iron incorporated into framework structure of MCM-41. The synthesized FeMCM-41 catalyst showed catalytic activities for propylene oxidation. Otherwise, there might be no attractive differences of catalytic activity among the addition steps of iron.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.396-400
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• 2014

The pore surface of mesoporous materials, SBA-15 and MCM-41 were functionalized with organosilanes, 3-aminopropyltrimethoxysilane (1NS) and N-[(3-trimethoxysilyl)propyl]ethylenediamine (2NS) via grafting method. $(n-BuCp)_2ZrCl_2$ and methylaluminoxane (MAO) were impregnated on the surface-functionalized mesoporous materials for the application to ethylene polymerization. In the case of SBA-15/2NS/$(n-BuCp)_2ZrCl_2$ supported Zr and Al contents decreased as grafted 2NS content increased. However, in the case of MCM-41/2NS/$(n-BuCp)_2ZrCl_2$ supported Al content decreased, but Zr content increased as grafted 2NS content increased. The polymerization activity of SBA-15/2NS/$(n-BuCp)_2ZrCl_2$ increased as the amount of grafted 2NS increased. Increase in the amount of grafted 2NS should caused decrease in pore volume and diameter. Consequently, it decreased the amount of supported metallocene and MAO in general. However, the smaller pore-sized MCM-41 could have lower supported MAO content due to its large molecular size in case that MCM-41 was surface-functionalized with 2NS. Therefore, the supported metallocene content could increase and its polymerization activity was higher than that of SBA-15.

• The Journal of the Korean bone and joint tumor society
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• v.13 no.2
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• pp.67-74
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• 2007

Purpose: To evaluate association of giant cell tumors recurrence between markers of proliferation cells (MCM3, Ki-67 and HH3) Materials and Methods: Ten case of giant cell tumor of bone were reviewed. The patients were six males and four females (mean age: 33 yrs). All patients were done operation after biopsy. The radiologic grading was determined according to Enneking grading system. The immunohistochemical stains of MCM3, HH3, and Ki-67 were done with Microarray block. Results: The three cases of 10 cases (30%) were recurred at same sites. Two case of recurrence was grade II according to radiologic features. The remaining case was grade I. The expression rate of immunohistochemical markers in radiologic grade 2 and 3 were more increased than grade 1. But there was not association between radiologic grading and proliferation of tumor cells because result data was not coherence. Mean MCM3 labeling index of non-recurred case was 11.2%, recurred case was 7.2%. Ki-67 was 12% vs. 8.9%, respectively and HH3 was 66.9 % vs. 75.4%, respectively. Thus there was no association between local recurrence and immunohistochemical Ki-67, MCM3 expression rate. But HH3 marker expression rate was increased in recurred cases compared to non-recurred cases. Conclusion: Our study suggests that HH3 immunohistochemical marker can be a useful prognostic factor.

• Korean Chemical Engineering Research
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• v.45 no.2
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• pp.117-123
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• 2007

The effect of aluminium addition to MCM-41 on product yield and carbon number distribution was investigated in the catalytic cracking of a polymer mixture, LDPE, LLDPE, and EVA copolymer, with a composition similar to that found in real agricultural film wastes. Al-MCM-41 catalyst synthesized by post-synthetic grafting method (Al-MCM-41-P) as well as Al-MCM-41 catalyst synthesized by direct sol-gel (Al-MCM-41-D). The catalytic cracking of polymer mixture was carried out in vapor phase contact as well as in liquid phase contact. The amount of acid sites increased with aluminium addition by post method as well as direct method, which was seemed to be due to Lewis acid sites. In liquid phase catalytic cracking, the yield of light hydrocarbon fraction increased with aluminium addition. The effect of aluminium addition on production of $C_5-C_{12}$ hydrocarbons over Al-MCM-41-P catalysts was greater than that over Al-MCM-41-D catalysts. In the case of vapor phase catalytic cracking, the effect of aluminium addition was smaller than that of liquid phase catalytic cracking. The selectivity to $C_{13}-C_{32}$ hydrocarbons was smaller in vapor phase catalytic cracking.

• Korean Journal of Environmental Agriculture
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• v.22 no.4
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• pp.284-289
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• 2003

Titanium mesoporous materials have received increasing attention as a new photocatalyst in the field for photocatalytic degradation of organic compounds. The photocatalytic degradation of chlorothalonil by mesoporous titanium oxo-phoswhate (Ti-MCM) was investigated in aqueous suspension for comparison with $TiO_2$, (Degussa, P25) using as an effective photocatalyst of organic pollutants. Mesoporous form of titanium Phosphate has been prepared by reaction of sulfuric acid and titanium isopropoxide in the presence or n-hexadecyltrimethylammonium bromide. The XRD patterns of Ti-MCM are hexagonal phases with d-spacings of 4.1 nm. Its adsorption isotherm for chlorothalonil reached at reaction equilibrium within 60 min under dark condition with 28% degradation efficiency. The degradation ratio of chlorothalonil after 9 hours under the UV radiation condition (254 nm) exhibited 100% by Ti-MCM and 88% by $TiO_2$. However, these degradation kinetics in static state showed a slow tendency compared to that of stirred state because of a low contact between titanium matrices and chlorothalonil. Also, degradation efficiency of chlorothalonil was increased with decreasing initial concentration and with increasing pH of solution. As results of this study, it was clear that mesoporous titanium oxo-phosphate with high surface area and crystallinity could be used to photo- catalytic degradation of various organic pollutants.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3196-3202
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• 2012

Post-synthesis is used to synthesize organic hybrid inorganic mesoporous sieves. In this method, the activity and structure of the base sieve are crucial to obtain the definable hybrid materials. The chemical and physical properties of the base can be largely changed either by the final step of its synthesizing processes, by template removal which is accomplished with the oxidative thermal decomposition (burning) method or by solvent extraction method. In this paper we compared two methods for the post-synthesis of organic hybrid MCM-48. When the template was extracted with HCl/alcohol mixture, the final product showed larger pore size, larger pore volume and better crystallinity compared to the case of the thermal decomposition. The reactivity of the surface silanol group of template free MCM-48 was also checked with an alkylsilylation reagent $CH_2=CHSi(OC_2H_5)_3$. Raman and $^{29}Si$ NMR spectra of MCM-48 in the test reaction indicated that more of the organic group was grafted to the surface of the sample after the template was removed with the solvent extraction method. Direct synthesis of vinyl-MCM-48 was also investigated and its characteristics were compared with the case of post-synthesis. From the results, it was suggested that the structure and chemical reactivity can be maintained in the solvent extraction method and that organic grafting after the solvent extraction can be a good candidate to synthesize a definable hybrid porous material.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.05a
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• pp.1171-1174
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• 2006

고신뢰도가 요구되는 위성용 탑재소프트웨어를 개발하기 위해서는 소프트웨어 처리기반으로 고성능의 탑재컴퓨터가 요구된다. 향후 개발될 위성을 위한 고성능 탑재컴퓨터로는 유럽에서 개발되어 사용되고 있는 MCM-ERC32를 채용할 예정이다. ESA(European Space Agency)의 지원 하에 개발된 MCM-ERC32는 32-비트의 ERC32SC 프로세서, 부가적인 기능을 제공하는 ASIC인 VASI(Very Advanced Sparc Interface), 그리고 메모리(SRAM, DRAM, EEPROM, etc.)로 구성되어 있다. MCM-ERC32에는 ERC32 프로세서에서 제공되는 2개의 UART(A/B)와 VASI에서 제공하는 4개의 UART(0/1/2/3), 총 6개의 시리얼 인터페이스가 있다. ERC32에서 제공하는 시리얼 인터페이스는 8-비트 모드만 지원되며 전송속도에도 제한이 있기 때문에 탑재소프트웨어의 업로드 및 디버깅용으로 활용될 예정이며, 탑재체 간의 인터페이스로는 VASI에서 제공하는 시리얼 인터페이스를 사용할 예정이다. VASI에서 제공하는 UART는 MCM-ERC32에 적합하도록 개발되어 일반적인 임베디드 시스템의 시리얼 인터페이스와는 구별되는 송수신 방법 및 기능을 제공한다. 본 논문에서는 이러한 VASI UART의 구성 및 특징과 기능들에 대하여 설명하도록 한다.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.608-614
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• 1998

In order to establish the scientific foundations for the production of Korean traditional kanjang (soy sauce) in a semi-pilot scale, meju preparation and kanjang mashing methods were investigated. Two types of meju, one that was prepared by conventional method (CM-meju) and the other that prepared by modified conventional method (MCM-meju), were made and compared their characteristics. The former made of cooked and crushed soybean with a brick shape was fermented at $15{\sim}20^{\circ}C\;and\;40{\sim}50%$ relative humidity (RH) for 30 days in koji room and the latter was fermented at $25{\sim}30^{\circ}C\;and\;80{\sim}90%$ RH seemingly being optimum for the growth of meju-organisms for the same period. The quality of MCM-meju as a raw material for the kanjang preparation was considered to be superior to that of CM-meju as the higher soluble nitrogen and total free amino acids content, the major factor for the evaluation of the quality of meju, were found in the former although the higher total nitrogen content and lower % weight loss were observed in the latter during meju preparation process. The quality of MCM-kanjang with higher total nitrogen, free amino acids, free sugars and the lower residual nitrogen content in cake after separation of kanjang was also found to be superior to that of CM-kanjang in sensory evaluation results.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.4
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• pp.1-7
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• 1999

We developed Fabrication process of embedded passive components in MCM-D substrate. The proposed MCM-D substrate is based on Cu/photosensitive BCB multilayer. The substrate used is Si wafer and Ti/cu metallization is used to form the interconnect layer. Interconnect layers are formed with 1000$\AA$ Ti/3000$\AA$ Cu by sputtering method and 3$\mu\textrm{m}$ Cu by electrical plating method. In order to form the vias in photosensitive BCB layer, the process of BCB and plasma etch using $C_2F_6$ gas were evaluated. The MCM-D substrate is composed of 5 dielectric layers and 4 interconnect layers. Embedded resistors are made with NiCr and implemented on the $2^{nd}$ dielectric layer. The sheet resistance of NiCr is controlled to be about 21 $\Omega$/sq at the thickness of 600$\AA$. The multi-turn sprial inductors are designed in coplanar fashion on the $4^{th}$ interconnect layer with an underpass from the center to outside using the lower $3^{rd}$ interconnect layer. Capacitors are designed and realized between $1^{st}$ interconnect layer and $2^{nd}$ interconnect layer. An important issue in capacitor is the accurate determination of the dielectric thickness. We use the 900$\AA$ thickness of PECVD silicon nitride film as dielectric. Capacitance per unit area is about 88nF/$\textrm {cm}^2$at the thickness of 900$\AA$. The advantage of this integration process is the compatibility with the conventional semiconductor process due to low temperature PECVD silicon nitride process and thermal evaporation NiCr process.