Porous Materials: Energy‐Efficient Dehumidification over Hierachically Porous Metal–Organic Frameworks as Advanced Water Adsorbents (Adv. Mater. 6/2012)

Seo, You‐,Kyong,Yoon, Ji Woong,Lee, Ji Sun,Hwang, Young Kyu,Jun, Chul‐,Ho,Chang, Jong‐,San,Wuttke, Stefan,Bazin, Philippe,Vimont, Alexandre,Daturi, Marco,Bourrelly, Sandrine,Llewelly WILEY‐VCH Verlag 2012 Advanced Materials Vol.24 No.6

<P>The energy‐efficient dehumidification over hier‐archically porous metal‐organic frameworks (MOFs) with hydrothermal stability is reported on page 806 by Jong‐San Chang and co‐workers. Their promising water sorption properties lead to a new type of advanced water adsorbents for the effective utilization of low‐grade thermal energy as well as solar energy. These MOFs would be potential alternatives to commercial water adsorbents, which are used for industrial or indoor desiccant applications such as desiccant dehumidifiers/humidifiers, gas dryers, adsorptive air‐conditioning systems, fresh water production, and adsorption heat transformation. </P>

이산화탄소 산화제를 이용한 탄화수소의 촉매 탈수소화 기술

장종산,박민석,정성화,박상언 한국공업화학회 2003 공업화학 Vol.14 No.6

온실가스로 잘 알려진 이산화탄소의 배출을 줄이기 위한 집중적인 연구가 지난 10년간 진행되었다. 대부분의 연구는 탄소 공급원으로서의 이산화탄소를 다양한 환원제를 써서 촉매반응에 활용하는 것에 집중되었다. 특히 부가가치가 높은 화합물을 얻기 위한 촉매 반응에 있어 이산화탄소의 산소원자를 떼어내기 위해 수소가 사용되어왔는데, 이 수소화 촉매 공정이 상업화되지 못하는 원인은 기존의 수증기 개질 등의 공정에서 제조되는 수소의 비용이 수소화 반응을 거친 최종 생산물의 가격보다 비싸기 때문이다. 따라서 이에 대한 대안으로서 ‘온화한 산화제’ 그리고 산소 전달 물질로서 이산화탄소의 활용이 주목되고 있다. 이산화탄소로부터 기인한 표면 산소은 지방족 탄화수소 뿐만 아니라 방향족 탄화수소의 산화반응에 활성이 있는 것으로 확인되었다. 이러한 접근은 이산화탄소 활용 기술의 새로운 분야를 열 것으로 기대된다. 주목할 것은 최근 이산화탄소가 산화제로 작용하여 에틸벤젠 탈 수소화 반응에 적용될 때 촉매 활성화 함께 스티렌 선택성이 향상되는 것으로 알려졌다. 또한 공정에 사용되는 수증기를 이산화탄소로 대체할 경우 에너지 절감 및 열역학적 평형 전환율이 상승되는 이점을 얻을 수 있다. 본 총설에서는 탄화수소의 산화적인 전환을 위한 이산화탄소 산화제 활용에 대한 시도들에 대해 살펴보겠다. For the mitigation of global warming due to carbon dioxide, catalytic conversions of CO_(2) with hydrogen has been extensively studied for the last decade. Most of studies in this field have been concentrated on the utilization of carbon dioxide as a carbon source through catalytic reduction processes with various kinds of reductants. However, catalytic hydrogenation has confronted with some limitations to be commercialized because of the use of expensive hydrogen as a reductant. As an altermative way, the utilization of CO_(2) as a soft oxidant and an oxygen transfer agent is attracting considerable attention. The oxygen species have been proven to be active in the oxidative conversions of aromatic hydrocarbons as well as aliphatic hydrocarbons. This approach may be expected to open new technology for CO_(2) utilization. In particular, it was found that carbon dioxide plays a role as an oxidant to increase catalytic activity and selectivity to styrene in dehydrogenation of ethylbenzene. In addition, the use of CO_(2) with replacement of steam gave beneficial advantages such as energy saving and increase in equilibrium conversion. In this short review, we attempt to integrate recent efforts on CO_(2) utilization as a soft oxidant for oxidative conversions of hydrocarbons.

자궁경부 편평상피병소에서 인체유두종바이러스 감염과 Ki-67표출에 대한 연구

김창진,강상균,이종칠 순천향의학연구소 1997 Journal of Soonchunhyang Medical Science Vol.3 No.2

The squamous cell carcinoma of the uterine cervix is the most common malignant tumor among women in Korea. Since 1976, when a research result that human papillomavirus(HPV) infection played some role in the tumorigenesis of the uterine cervical carcinoma had been published, numerous reports supporting the result has been released. They reported that about 90% of the carcinoma had some relation with HPV infections. About 20 subtypes of HPV has been observed in the anogenital lesions. As subtypes of the virus can be grouped into three according to the potentiality of malignant tumorigenesis, high risk group (HPV16, 18), intermediate risk group(HPV31, 33)and low risk group(HPV6/11), it is very important to identify the subgroups in the precancerous and cancerous lesions of the cervix for either diagnosis or prognosis. When HPV infects the epithelial cells, it promotes cellular proliferation. The cellular proliferation can be evaluated by immunohistochemistry with the antibodies for proliferting cell nuclear antigen(PCNA) and KI-67. Because PCNA has long half-life, and can be detected 48 hours after completion of mitosis, an estimation of proliferating cells by PCNA could be inaccurate. The expression of Ki-67 antigen is more correct than PCNA for the evaluation of proliferating cells due to its short half-life and rapid degradaton after completion of the mitosis. This study was conducted to see the relation between subtypes of HPV and cell proliferation by in situ hybridization(ISH) and immunohistochemistry in 60 cases of squamous intraepithelial lesions(SILs) and invasive carcinoma of the uterine cervix. The results are as follows; 1. HPV was detected in 50 out of 60 cases (83.5%). 2. The subtypes HPV6/11, the low risk group, were detected in 78.2% and 4.5% of low grade SIL and high grade SIL respectively, while not detected in any of invasive carcinomas. 3. The subtypes HPV 16, 18, the high risk groups, were detected in 4.3%, 59.1% and 80% of low grade SIL, high grade SIL and invasive carcinomas respectively. 4. In normal squamous epithelium and squamous metaplasia, the cell fraction expressing Ki-67 were 13.5%±6.7% and 8.7%±3.5%, while in low grade SIL, high grade SIL and invasive carcinomas they were 35.8±7.9%, 66.8±11.8% and 84±13.4% resepectively. 5. There was no relation between HPV subtypes and cell fractions expressing Ki-67. Above results shows that subtypes HPV6/11 are prevalent in low grade SILs, while HPV16, 18 are common in the high grade SIL and invasive carcinoma. It seems that there is no correlation between the cell fractions expressing Ki-67 and subtypes of HPV, which suggests that cellular proliferation can be induced by other than HPV infections. As the cell fraction expressing Ki-67 increases according to the grade of SIL and invasiveness, it would be useful prognostic factor along with the identification of high risk HPV type in the uterine cervical squamous epithelial lesions.

1LF-5 : Nanoporous Materials and Nancatalysts

( Jong-san Chang ),( Jin-soo Hwang ),( Sang-eon Park ) 한국공업화학회 2003 한국공업화학회 연구논문 초록집 Vol.2003 No.-

Nanoporous Materials and Nancatalysts

( Jong-san Chang ),( Jin-soo Hwang ),( Sang-eon Park ) 한국공업화학회 2003 한국공업화학회 연구논문 초록집 Vol.2003 No.1

Syntheses and Applications of Nanocatalysts Based on Nanoporous Materials

Chang, Jong-San,Jhung, Sung Hwa,Hwang, Young Kyu,Park, Sang-Eon,Hwang, Jin-Soo WILEY-VCH Verlag 2006 Chem Inform Vol.37 No.40

<P>ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.</P>

Selective Hydrogenation of 1,3-Butadiene over Supported Nickel Catalyst Obtained from Nickel-Zirconia Solid Solution

Chang, Jong-San,Ryu, Jae-Oak,Lee, Jong-Min,Park, Sang-Eon,Hong, Do-Young,Jhung, Sung-Hwa Korean Chemical Society 2005 Bulletin of the Korean Chemical Society Vol.26 No.10

Catalytic properties of Ni-Zr$O_2$ catalysts prepared by coprecipitation have been studied for the gas-phase hydrogenation of 1,3-butadiene to butenes. The coprecipitation method led to the solid solution of Ni-Zr$O_2$, which contains highly resistant Ni species to thermal reduction with H2. Nickel species of the solid solution were highly dispersed in the ZrO2 lattice, so that the reduced catalysts were selective for hydrogenation of 1,3-butadiene to butenes (99.9%) even in the presence of 1-butene.

Dehydrogenation of Ethylbenzene with Carbon Dioxide as Soft Oxidant over Supported Vanadium-Antimony Oxide Catalyst

Jong-San Chang,Vladislav P. Vislovskiy,박상언,Min-Seok Park,Jin S. Yoo,홍도영 대한화학회 2005 Bulletin of the Korean Chemical Society Vol.26 No.11

This work presents that carbon dioxide, which is a main contributor to the global warming effect, could be utilized as a selective oxidant in the oxidative dehydrogenation of ethylbenzene. The dehydrogenation of ethylbenzene over alumina-supported vanadium-antimony oxide catalyst has been studied under different atmospheres such as inert nitrogen, steam, oxygen or carbon dioxide as diluent or oxidant. Among them, the addition of carbon dioxide gave the highest styrene yield (up to 82%) and styrene selectivity (up to 97%) along with stable activity. Carbon dioxide could play a beneficial role of a selective oxidant in the improvement of the catalytic behavior through the oxidative pathway.

Selective Crystallization of SAPO-5 and SAPO-34 Molecular Sieves in Alkaline Condition: Effect of Heating Method

Jong-San Chang,정성화,김영호,박상언,윤지웅 대한화학회 2005 Bulletin of the Korean Chemical Society Vol.26 No.4

Crystallization of SAPO-5 and SAPO-34 molecular sieves with microwave and conventional electric heating of the same gel has been investigated in an alkaline condition using N,N,N’,N’-tetraethylethylenediamine as a template molecule. SAPO-5 structure can be selectively prepared with microwave heating because of the fast crystallization of the technique. On the other hand, SAPO-34 is the sole product with usual conventional electric heating because SAPO-5 can be gradually transformed into SAPO-34 structure with an increase in crystallization time. This phase selectivity is probably because of the relative stability of the two phases at the reaction conditions (kinetic effect). Crystallization with microwave heating can be suggested as a phase selective synthesis method for relatively unstable materials because of fast crystallization.

Propane Dehydrogenation over a Hydrogen Permselective Membrane Reactor

Chang, Jong-San,Roh, Hyun-Seog,Park, Min-Seok,Park, Sang-Eon Korean Chemical Society 2002 Bulletin of the Korean Chemical Society Vol.23 No.5

The dehydrogenation of propane to propylene has been studied in an isothermal high-temperature shell-and-tube membrane reactor containing a Pd-coated ${\psi}$-Al2O3 membrane and a Pt/K/Sn/Al2O3 packed catalyst . A tubular Pd-coated ${\psi}$-Al2O3 membrane was prepared by an electroless plating method. This membrane showed high hydrogen to nitrogen permselectivities (PH2N2 = 10-50) at 400 $^{\circ}C$ and 500 $^{\circ}C$ with various transmembrane pressure drops. The employment of a membrane reactor in the dehydrogenation reaction, which selectively separates hydrogen from the reaction mixture along the reaction path, can greatly increase the conversion and enable operation of the reactor at lower temperatures. High hydrogen permselectivity has been confirmed as a key factor in determining the reactor performance of conversion enhancement.