• 제목/요약/키워드: platinium

검색결과 12건 처리시간 0.029초

금속유기물증착법에 의한 $La_2Ti_2O_{7}$ 박막의 제조 (Fabrication of $La_2Ti_2O_{7}$ Film by Metalorganic Deposition)

  • 조경호;우동찬;박철우;이희영;남효덕
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
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    • pp.122-125
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    • 1995
  • Using metalorganic deposition technique, $La_2Ti_2O_{7}$ precursor solution was deposited on platinium coated SiO$_2$/SI(100) substrates by spin-coating process. Crystalline and crack-free films of ∼0.2$\mu\textrm{m}$ thickness were successfully fabricated on the above substrate from four different types of $La_2Ti_2O_{7}$ precursor solutions by proper heat treatment in the temperature range of $700^{\circ}C$$1200^{\circ}C$. Microstructure and X-ray diffraction analysis of $La_2Ti_2O_{7}$ thin film showed that the crystallization temperature and the preferred orientation of $La_2Ti_2O_{7}$ thin film were strongly dependent on the precursor used.

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Metaplastic Breast Carcinoma: Case Series and Review of the Literature

  • Esbah, Onur;Turkoz, Fatma P.;Turker, Ibrahim;Durnali, Ayse;Ekinci, Ahmet S.;Bal, Oznur;Sonmez, Ozlem Uysal;Budakoglu, Burcin;Arslan, Ulku Y.;Oksuzoglu, Berna
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권9호
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    • pp.4645-4649
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    • 2012
  • Metaplastic breast carcinoma (MpBC) is a rare disease entity, accounting for less than 1% of all breast carcinomas. Furthermore, it is a heterogenous disease with different subgroups, including malignant epithelial (carcinoma) and stromal (sarcoma) features. Here we evaluated, retrospectively, 14 female MpBC patients admitted to Ankara Oncology Training and Research Hospital between 2005 and 2011. Median age was 45.5 (range:16.0-76.0) and tumor size 57.5 mm (range: 20.0-80.0 mm). Histopathological subtypes were as follows: 5 carcinosarcoma, 5 squamous and 4 adenosquamous carcinoma. All but one with upfront lung metastasis, had their primary breast tumor operated. Axillary lymph nodes were involved in 64.3%. The most common sites of metastasis were lungs and brain. Chemotherapy including antracycline, taxane and even platinium was planned for adjuvant, neoadjuvant and palliative purposes in 9, 3 and 1 patient, respectively. Median cycles of chemotherapy was 6 (range:4-8). Median follow-up of the patients was 52 months (95%CI 10.4-93.6 month). Median 3 year progression free survival (PFS) and overall survival (OS) in this patients cohort were 33% and 56%, respectively. In conclusion, MpBC is a rare and orphan disease without standardized treatment approaches and the prognosis is poor so that larger studies to investigate different treatment schedules are urgently needed.

$TiO_2$ 두께에 따른 염료감응형 태양전지의 전기화학적 임피던스 분석 (Electrochemical Impedance Spectroscopy Analysis on the Dye-sensitized Solar Cell with Different $TiO_2$ thicknesses)

  • 김희제;이정기;서현웅;손민규;김진경;프라바카르;신인영
    • 전기학회논문지
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    • 제58권12호
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    • pp.2425-2430
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    • 2009
  • Dye-sensitized solar cell(DSC) is composed of a dye-adsorbed nanoporous $TiO_2$ layer on fluorine-doped tin oxide(FTO) glass substrate, electrolyte, and platinium doped counter electrode. Among these, a dye-absorbed nanoporous $TiO_2$ layer plays an important role in the performance of the DSC because the injected electrons from excited dye molecules move through this layer. And the condition of $TiO_2$ layer such as the morphology and thickness affects on the electron movement. Therefore, the performances and the efficiency of DSC change as the thickness of $TiO_2$ layer is different. Electrochemical Impedance Spectroscopy(EIS) is the powerful analysis method to study the kinetics of electrochemical and photoelectrochemical processes occurring in the DSC especially the injected electron movements. So we analyzed the DSCs with different $TiO_2$ thicknesses by using EIS to understand the influence of the $TiO_2$ thickness to the performance of the DSC clearly. Finally, we got the EIS analysis on the DSC with different $TiO_2$ thickness from the internal resistance of the DSC, the electron life time and the amount of dye molecules.

Predictors of Outcome in Patients with Advanced Nonseminomatous Germ Cell Testicular Tumors

  • Yetisyigit, Tarkan;Babacan, Nalan;Urun, Yuksel;Seber, Erdogan Selcuk;Cihan, Sener;Arpaci, Erkan;Yildirim, Nuriye;Aksoy, Sercan;Budakoglu, Burcin;Zengin, Nurullah;Oksuzoglu, Berna;Yalcin, Banu Cicek;Alkis, Necati
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권2호
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    • pp.831-835
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    • 2014
  • Background: Predictor factors determining complete response to treatment are still not clearly defined. We aimed to evaluate clinicopathological features, risk factors, treatment responses, and survival analysis of patient with advanced nonseminomatous GCTs (NSGCTs). Materials and Methods: Between November 1999 and September 2011, 140 patients with stage II and III NSGCTs were referred to our institutions and 125 patients with complete clinical data were included in this retrospective study. Four cycles of BEP regimen were applied as a first-line treatment. Salvage chemotherapy and/or high-dose chemotherapy (HDCT) with autologous stem cell transplantation were given in patients who progressed after BEP chemotherapy. Post-chemotherapy surgery was performed in selected patients with incomplete radiographic response and normal tumor markers. Results: The median age was 28 years. For the good, intermediate and poor risk groups, compete response rates (CRR) were, 84.6%, 67.9% and 59.4%, respectively. Extragonadal tumors, stage 3 disease, intermediate and poor risk factors, rete testis invasion were associated with worse outcomes. There were 32 patients (25.6%) with non-CR who were treated with salvage treatment. Thirty-one patients died from GCTs and 94% of them had stage III disease. Conclusions: Even though response rates are high, some patients with GCTs still need salvage treatment and cure cannot be achieved. Non-complete response to platinium-based first-line treatment is a negative prognostic factor. Our study confirmed the need for a prognostic and predictive model and more effective salvage approaches.

백금 스크랩으로부터 아민산백금용액 제조 및 Soot Oxidation 특성 (Preparation of Platinum Amine Complex Solution from Pt Scrap and its Catalytic Activity of Soot Oxidation)

  • 최승훈
    • 자원리싸이클링
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    • 제27권3호
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    • pp.93-99
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    • 2018
  • 본 연구에서는 디스플레이 산업의 백금 폐스크랩을 용해, 용매추출을 통하여 백금족 성분을 효율적으로 추출하고, 추출된 백금용액을 디젤자동차 배가스 정화촉매용 전구체 용액으로서 제조하고, 그 촉매활성을 실험하였다. 용액화학적 이론 연구를 통하여 백금 화학종의 수용액상 거동을 조사하였고, 화학종들의 존재영역 및 거동을 근거로 추출 및 분리 가능방안을 수립하였다. 전기화학적 방법에 의해 폐스크랩을 용해시킴으로써, 용해시간 단축 및 추출효율을 높였으며, 로듐 성분을 분리 제거, TBP에 의한 용매추출, 염산에 의한 탈거 공정을 거쳐 Pt-Chloride-$H_2O$ 계 백금용액을 용액을 제조하고, 이 용액을 원료로 액상 아민화 반응을 통해 아민산 백금용액을 제조한 다음, 카본블랙의 연소반응에 대한 촉매 활성을 실험함으로써, 백금족 폐스크랩으로부터 고부가 백금족 화합물의 제조가능성을 연구하였다.

Electrochemical degradation of Orange G in K2SO4 and KCl medium

  • Hamous, Hanene;Khenifi, Aicha;Bouberka, Zohra;Derriche, Zoubir
    • Environmental Engineering Research
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    • 제25권4호
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    • pp.571-578
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    • 2020
  • In this work, a detailed study on the electrochemical degradation of an azo dye, Orange G is performed using a platinum electrode. Indeed, the influence of the dye concentration (50-150 mg/L), the pH of the medium and the density of the electric current is studied on the rate of discoloration, the rate of mineralization, the efficiency of the electric current and the energy consumption. The UV-visible spectra of OG plotted against the degradation time show the decrease of the intensity of the characteristic dye peaks. In an environment rich in chlorides, all peaks disappear after 15 min of degradation. However, the peaks at wavelengths of 200 and 290 nm appeared after one hour of treatment. In K2SO4, the eliminated percentages are respectively 46, 54 and 61% for wavelengths of 245, 330 and 480 nm. This suggests that the degradation mechanisms in K2SO4 and KCl environments are not the same. In the middle rich in chlorides, the eliminated percentage of OG did not seem to be affected by the concentrations increase. These results confirm the hypothesis that electrochemical oxidation process is very favorable for concentrated pollutants discharge.

수열법에 의한 calcite$(CaCO_3)$ 단결정 성장 (Growth of calcite$(CaCO_3)$ single crystal by hydrothermal method)

  • 이영국;유영문;박로학
    • 한국결정학회지
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    • 제7권1호
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    • pp.30-35
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    • 1996
  • 수열법에 의해 고온 고압용 autoclave내에서 calcite 단결정을 성장하였으며, 자외-가시영역에서의 투과율 등을 측정하였다. Calcite 단결정 성자에 관해 보고된 광화제로는 6M의 M2CO3(M=K, Rb)와 chloride등이 있는데 강알카리의 경우 성장속도는 크나 autoclave를 백금으로 내장해야 하며 chloride의 경우 자발 핵생성에 의한 성장(spontaneous nucleation and growth)의 경향이 강하여 종자결정위에서 성장하는 것에 비해 autoclave 벽면 위에서 자발 핵생성에 의한 성장이 더 우세한 것으로 알려져 있다. 본 연구에서는 autoclave의 내장재료로 고가의 백금대신 테프론을 사용하고자 성장온도가 테프론의 내온(280℃)에서 NH4Cl을 광화제로 사용하여 calcite 단결정을 성장하였다. 연구결과 NH4Cl 수열용액으로 calcite 단결정을 성장할 때 자발 핵생성을 억제하려면 NaCl 또는 CH3COOH가 소량 첨가된 수열용액에서 온도구배를 6-7℃ 이하로 유지하여 성장하여야 함을 확인하였다. 성장된 calcite의 자외 및 청색 가시영역에서 투과율은 80% 정도로 천연보다 약 10% 높았다.

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산소환원반응을 위한 탄화철이 내재된 질소 도핑된 탄소의 제조 (Synthesis of Fe3C-Embedded Nitrogen Doped Carbon for Oxygen Reduction Reaction)

  • 이영근;안건형;안효진
    • 한국재료학회지
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    • 제28권11호
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    • pp.640-645
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    • 2018
  • The design of non-precious electrocatalysts with low-cost, good stability, and an improved oxygen reduction reaction(ORR) to replace the platinium-based electrocatalyst is significant for application of fuel cells and metal-air batteries with high energy density. In this study, we synthesize iron-carbide($Fe_3C$) embedded nitrogen(N) doped carbon nanofiber(CNF) as electrocatalysts for ORRs using electrospinning, precursor deposition, and carbonization. To optimize electrochemical performance, we study the three stages according to different amounts of iron precursor. Among them, $Fe_3C$-embedded N doped CNF-1 exhibits the most improved electrochemical performance with a high onset potential of -0.18 V, a high $E_{1/2}$ of -0.29 V, and a nearly four-electron pathway (n = 3.77). In addition, $Fe_3C$-embedded N doped CNF-1 displays exellent long-term stabillity with the lowest ${\Delta}E_{1/2}=8mV$ compared to the other electrocatalysts. The improved electrochemical properties are attributed to synergestic effect of N-doping and well-dispersed iron carbide embedded in CNF. Consequently, $Fe_3C$-embedded N doped CNF is a promising candidate for non-precious electrocatalysts for high-performance ORRs.

Octamethylenethiafulvalene과 염화오스뮴, 이리듐, 백금 및 금 화합물의 합성과 특성에 관한 연구 (Synthesis and Characterization of Octamethylenethiafulvalene Compounds with Osmium, Iridium, Platinium and Gold Chloride)

  • 정찬규;이홍우;김영진;최성낙;김영인
    • 대한화학회지
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    • 제45권5호
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    • pp.442-447
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    • 2001
  • Octamethylenethiafulvalene(OMTTF)와 $HAuCl_4{\cdot}3H_2O$를 THF 용액 내에서 직접 반응시켜 $(OMTTF)AuCl_4$를 합성하였다. $(OMTTF)_2PtCl_4,\; (OMTTF)_2\;IrCl6{\cdot}2H_2O,\; (OMTTF)OsCl5{\cdot}THF$ 등은 각각 $H_2PtCl_6{\cdot}xH_2O,\;H_2IrCl_6{\cdot}xH_2O$$H_2OsCl_6$를 사용하여 유사한 방법으로 합성하였다. 합성된 화합물들은 자기적(EPR, 자화율 측정), 분광학적(IR, UV-Vis), 전기화학적(CV) 특성과 전기전도도를 측정하였다. 상온에서의 분말 전기전도도는 모두 ~$10^{-7}\; S{\cdot}cm^{-1}$ 이하의 낮은 전기전도도를 나타내었다. 합성 과정에서 OMTTF로부터 Au, Pt, Ir, Os 금속 화합물로 전하 이동이 이루어져 OMTTF는 완전히 이온화된 $OMTTF^+$ 양이온 라디칼로 존재하였다. $OMTTF^+$ 양이온 라디칼의 안정성은 산화·환원 전위 값에서 확인하였다. 자화율 결과로부터 $(OMTTF)_2IrCl_6{\cdot}2H_2O$$(OMTTF)OsCl5{\cdot}THF$에서는 $OMTTF^+$ 이온에 존재하는 홀전자와 중심 금속(Ir 및 Os)에 편재화된 홀전자들 사이에는 강한 반강자성 상호작용이 존재함을 알 수 있었다.

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