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781.
Areum Kim Hyunjin Park Eunmi Choi Yinhua Cui Seon Jea Lee Sung Gyu Pyo 《Israel journal of chemistry》2015,55(10):1070-1074
In this paper, we describe selective deposition of a major electrode and a protection electrode in a heterojunction with intrinsic thin-layer (HIT) type solar cell. Sn and Ni were used for the protection electrode to prevent the oxidation of Cu, which was used for the main electrode. SEM and TEM were used to analyze the microstructural evolution and changes in the interface as a result of each electroless deposition. Finally, the performance of our solar cell created via electroless deposition was evaluated. We determined the photovoltaic conversion efficiency (PCE) to be 16.4 %, the fill factor (FF) to be 72.2 %, the open circuit voltage (Voc) to be 681 mV, and the short circuit current (Jsc) to be 33.0 mA/cm2. These output values match the performance of an Ag screen-printed solar cell and demonstrate the possibility of commercializing an inexpensive HIT solar cell with high efficiency. 相似文献
782.
Gerard Chew Moti Schneider Abraham Kandel Gideon Langholz 《Computer-Aided Civil and Infrastructure Engineering》1995,10(3):213-222
Abstract: This paper demonstrates a mechanism for incorporating and independently evaluating membership functions and certainty factors during the preprocessing phrase in fuzzy expert systems. By providing this flexibility within the framework of a fuzzy expert system tool, the expert system becomes better equipped to model real-world control applications. 相似文献
783.
Woon Yong Choi Ji Seon Kim Sung Jin Park Choong Je Ma Hyeon Yong Lee 《International journal of molecular sciences》2014,15(4):5907-5915
In this study, the effect of Codonopsis lanceolata fermented by lactic acid on controlling gene expression levels related to obesity was observed in an oligonucleotide chip microarray. Among 8170 genes, 393 genes were up regulated and 760 genes were down regulated in feeding the fermented C. lanceolata (FCL). Another 374 genes were up regulated and 527 genes down regulated without feeding the sample. The genes were not affected by the FCL sample. It was interesting that among those genes, Chytochrome P450, Dmbt1, LOC76487, and thyroid hormones, etc., were mostly up or down regulated. These genes are more related to lipid synthesis. We could conclude that the FCL possibly controlled the gene expression levels related to lipid synthesis, which resulted in reducing obesity. However, more detailed protein expression experiments should be carried out. 相似文献
784.
The solubility of water vapour in the CaO‐SiO2‐Al2O3‐MgO quaternary slag system was measured using an inert gas fusion technique with thermal conductivity detection. The slags were equilibrated with argon‐water vapour mixture corresponding to 0.157 bar of water vapour pressure at 1873 K. The slag solubility of water vapour is proportional to the square root of vapour pressure. Since the hydroxyl capacity of slag, COH shows an independence on the relative amount of CaO or MgO in slag, the contributions of CaO and MgO on the hydroxyl capacity are equivalent on a molar basis. Whereas, Al2O3 shows a better effect on the hydroxyl capacity than SiO2. A linear relationship between hydroxyl capacity and slag basicity in logarithmic scale was obtained with the slope of 1/2, confirming the water vapour dissolution reaction into a basic slag as (O2‐) + H2O(g) = 2(OH?). The correlation between hydroxyl capacity and slag components was derived in terms of their contributing weight factors. The measured values of C'OH agree well with the calculated ones using the interaction energies of αH‐Al = ?38300 and αH‐Mg = ?22700 J determined with the aid of the regular solution model. In addition, the correlation between hydroxyl capacity and sulphide capacity was empirically derived as a formula of logCOH = 1/2logCS + (4.38 ± 0.25) through the thermodynamic expression of both capacities by virtue of the common oxygen ion activity. 相似文献
785.
The discharging properties of tundish slag for an improved hot‐tundish recycling process were investigated using a lab‐scale discharging experiment at 1773 K. The sticking ratio of the slag (defined as the weight ratio of the sticking slag on a Al2O3 crucible after discharging to the total slag at the moment of discharging) was found to decrease with increasing basicity ((%CaO)/(%SiO2)), FetO content and discharging temperature, and decreasing Al2O3 content. While the substitution of MgO for CaO increases the sticking ratio, Al2O3 and SiO2 show nearly identical effects on it. The experimental results were discussed in terms of the physical properties of slag, viz. viscosity and wettability. Finally, both sticking ratio and erosion tendency were linked with optical basicity, and an optimum region of slag composition for an improved hot‐tundish recycling process was proposed. With the proposed slag condition, the suitability of the plant slags for an optimized process was investigated. 相似文献
786.
The design and synthesis of cellular structured materials are of both scientific and technological importance since they can impart remarkably improved material properties such as low density, high mechanical strength, and adjustable surface functionality compared to their bulk counterparts. Although reducing the density of porous structures would generally result in reductions in mechanical properties, this challenge can be addressed by introducing a structural hierarchy and using mechanically reinforced constituent materials. Thus, precise control over several design factors in structuring, including the type of constituent, symmetry of architectures, and dimension of the unit cells, is extremely important for maximizing the targeted performance. The feasibility of lightweight materials for advanced applications is broadly explored due to recent advances in synthetic approaches for different types of cellular architectures. Here, an overview of the development of lightweight cellular materials according to the structural interconnectivity and randomness of the internal pores is provided. Starting from a fundamental study on how material density is associated with mechanical performance, the resulting structural and mechanical properties of cellular materials are investigated for potential applications such as energy/mass absorption and electrical and thermal management. Finally, current challenges and perspectives on high‐performance ultra‐lightweight materials potentially implementable by well‐controlled cellular architectures are discussed. 相似文献
787.
In the present study, we developed an antitumor immunoconjugate that appears to be promising as a novel curative antitumor agent against a variety of human solid tumors. We generated a new antihuman endoglin (EDG) monoclonal antibody (mAb) K4-2C10 (or termed SN6f) that cross-reacts with mouse endothelial cells. Such cross-reactive anti-EDG mAbs have not been reported previously. This mAb was used to target tumor-associated vasculature in SCID mice inoculated with human tumors. No anti-EDG mAb or its immunoconjugates have previously been successfully used for targeting vasculature in vivo. In this study, MCF-7 human breast cancer cells were inoculated s.c. into SCID mice. K4-2C10 did not react with the MCF-7 cells but showed a weak reactivity with mouse endothelial cells. The mAb reacted with the proliferating endothelial cells more strongly than with the quiescent endothelial cells. The mAb exhibited much stronger reactivity (>10-fold) with human endothelial cells than with mouse endothelial cells and reacted strongly with vascular endothelium of tumor-associated blood vessels in a variety of human malignant tissues. Conjugates of K4-2C10 with ricin A chain (RA) and deglycosylated ricin A chain (dgRA) showed a weak but specific cytotoxic activity against murine endothelial cells in vitro; the 50% inhibitory dose of the RA and dgRA conjugates was 54 nm and 29 nm, respectively. Remarkable antitumor efficacy was observed when a small amount (a total of 60 microgram corresponding to 24% of the LD50 dose) of the dgRA conjugate was administered i.v. into SCID mice that had been inoculated s.c. with MCF-7. Unconjugated mAb K4-2C10 was not significantly effective in the inhibition of the tumor growth. The immunotoxin (IT) completely inhibited growth of the tumor in all of the treated mice (n = 8). Furthermore, similar antitumor efficacy was observed when the IT was administered i.v. into the tumor-inoculated SCID mice that had been pretreated with unconjugated K4-2C10 to block the potentially available weak binding sites of normal tissues. The strong therapeutic effects of the IT were reproduced in another set of therapeutic experiments. No significant side effects were observed in the mice. The differences in the tumor growth between the control group and the IT-treated groups were statistically significant. The IT showed antiangiogenic activity in the dorsal air sac method. The results indicate that K4-2C10 IT effectively treated the tumor-bearing mice by selectively inhibiting the tumor-associated blood vessels and by disrupting tumor-associated angiogenesis. The strong antitumor efficacy of the K4-2C10 IT is remarkable in view of the fact that K4-2C10 and its IT showed only a weak reactivity with mouse endothelial cells, and a relatively small amount of the IT was administered i.v. to treat s.c. tumors. We anticipate that the K4-2C10 IT will show much stronger antitumor efficacy and antiangiogenic activity in patients with solid tumors and other angiogenesis-associated diseases. The present results demonstrate for the first time that an anti-EDG mAb or its immunoconjugate can effectively target tumor-associated vasculature in vivo. 相似文献
788.
Ji Hui Kim Kwon-Yeong Lee Kang Hee Ko Ji Young Kim Ki Nam Kim Joon Young Oh Seon Jin Kim 《Wear》2009,266(11-12):1137-1140
The effects of nickel and carbon concentrations on the wear resistance of Fe–xNi–yC (x = 14–20 wt.%, y = 0.6–1.0 wt.%) were investigated with respect to strain energy initiation of the martensitic transformation and hardness. The strain energy needed to initiate the martensitic transformation increased with increasing carbon and nickel concentrations, except in 1.0 wt.% C alloys. The wear resistance of the material decreased with increasing carbon concentration up to 0.9 wt.% C. This effect is most likely due to decrement of the martensite volume fraction with increasing carbon concentration induced by the incremental strain energy required to begin the martensitic transformation. In the case of 1.0 wt.% C, the improved wear resistance may be due to carbide precipitation. 相似文献
789.
Byung Seon Yoon Joon Young Joang Moon Ho Suh Yong Mu Lee Suck Hyun Lee 《Polymer Composites》1997,18(6):757-764
The properties of polypropylene (PP)/polyamide 6 (PA) blends, obtained by the following two different blending methods, were investigated. Blends of PP/PA and PP/PA/maleic anhydride have been prepared using a twin screw extruder and a fiber cutting, flying and mixing apparatus that directly commingles PP fiber and PA fiber. The properties measured include rheological properties by means of a capillary rheometer, morphologies by scanning electron microscopy, and mechanical properties by a universal testing machine and a high rate impact tester. In the presence of compatibilizer, a marked dispersibility of the polymer blends of PP and PA was observed, and mechanical properties were found to increase as a result of improvement of the interfacial adhesion and the dispersibility. The properties of PP/PA blends manufactured by two different pieces of equipment were shown to be similar in the case of melting both resins. But in particular, superior impact properties were obtained in blends not melting PA fibers as a dispersed phase rather than blends using maleic anhydride grafted polypropylene (PP-g-MA) as a compatibilizer. 相似文献