• 제목/요약/키워드: Inorganic lead

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Low-Temperature Processable Charge Transporting Materials for the Flexible Perovskite Solar Cells

  • Jo, Jea Woong;Yoo, Yongseok;Jeong, Taehee;Ahn, SeJin;Ko, Min Jae
    • Electronic Materials Letters
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    • 제14권6호
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    • pp.657-668
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    • 2018
  • Organic-inorganic hybrid lead halide perovskites have been extensively investigated for various optoelectronic applications. Particularly, owing to their ability to form highly crystalline and homogeneous films utilizing low-temperature solution processes (< $150^{\circ}C$), perovskites have become promising photoactive materials for realizing high-performance flexible solar cells. However, the current use of mesoporous $TiO_2$ scaff olds, which require high-temperature sintering processes (> $400^{\circ}C$), has limited the fabrication of perovskite solar cells on flexible substrates. Therefore, the development of a low-temperature processable charge-transporting layer has emerged as an urgent task for achieving flexible perovskite solar cells. This review summarizes the recent progress in low-temperature processable electron- and hole-transporting layer materials, which contribute to improved device performance in flexible perovskite solar cells.

Trace Mineral Nutrition in Poultry and Swine

  • Richards, James D.;Zhao, Junmei;Harrell, Robert J.;Atwell, Cindy A.;Dibner, Julia J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권11호
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    • pp.1527-1534
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    • 2010
  • Trace minerals such as zinc, copper, and manganese are essential cofactors for hundreds of cellular enzymes and transcription factors in all animal species, and thus participate in a wide variety of biochemical processes. Immune development and response, tissue and bone development and integrity, protection against oxidative stress, and cellular growth and division are just a few examples. Deficiencies in trace minerals can lead to deficits in any of these processes, as well as reductions in growth performance. As such, most animal diets are supplemented with inorganic and/or organic forms of trace minerals. Inorganic trace minerals (ITM) such as sulfates and oxides form the bulk of trace mineral supplementation, but these forms of minerals are well known to be prone to dietary antagonisms. Feeding high-quality chelated trace minerals or other classes of organic trace minerals (OTM) can provide the animal with more bioavailable forms of the minerals. Interestingly, many, if not most, published experiments show little or no difference in the bioavailability of OTMs versus ITMs. In some cases, it appears that there truly is no difference. However, real differences in bioavailability can be masked if source comparisons are not made on the linear portion of the dose-response curve. When highly bioavailable chelated minerals are fed, they will better supply the biochemical systems of the cells of the animal, leading to a wide variety of benefits in both poultry and swine. Indeed, the use of certain chelated trace minerals has been shown to enhance mineral uptake, and improve the immune response, oxidative stress management, and tissue and bone development and strength. Furthermore, the higher bioavailability of these trace minerals allows the producer to achieve similar or improved performance, at reduced levels of trace mineral inclusion.

베타/감마 동시 측정용 광섬유 이중 검출기의 개발을 위한 기초연구 (Feasibility Study on Development of a Fiber-Optic Dual Detector to Measure Beta- and Gamma-rays Simultaneously)

  • 홍승한;신상훈;심혁인;김선근;전혜수;장재석;김재석;권구원;장경원;유욱재;이봉수
    • 전기학회논문지
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    • 제63권2호
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    • pp.284-290
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    • 2014
  • A fiber-optic beta/gamma dual detector system with two types of sensing probes was fabricated to detect the beta- and gamma-rays simultaneously. As scintillators of the sensing probe type 1, two different inorganic scintillators, $CaF_2(Eu)$ and LYSO(Ce) crystals, were used to obtain the each scintillating efficiency with respect to beta-and gamma-rays and the inherent energy spectra of radioactive isotopes. In the case of the sensing probe type 2, which is composed of two identical inorganic scintillators and a beta shielding material based on the lead, it could discriminate beta- and gamma-rays using a subtraction method. In conclusion, we demonstrated that the proposed fiber-optic beta/gamma dual detector could measure and discriminate beta- and gamma-rays using both energy spectroscopy and subtraction method.

과학적 분석에 의한 은해사 괘불탱의 상태 및 재료 해석 (Scientific Study of Characteristics and Material Properties of Hanging Painting of Eunhaesa Temple)

  • 이은우;경유진;윤지현;권윤미;송정원;서민석;이장존
    • 보존과학회지
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    • 제35권6호
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    • pp.689-700
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    • 2019
  • 본 연구는 은해사에 소장되어 있는 보물 제1270호 은해사 괘불탱에 대한 과학적 조사와 분석을 실시하여 보존 상태, 재질 및 채색 안료 등에 대한 성격과 특징을 해석하고자 하였다. 대상의 미술사적 배경을 짚어보고 보존적 측면의 상태조사 및 안료 색상별 재료적 특성을 알기 위한 분석을 실시하였다. 그 결과 연백, 연단, 활석, 진사, 석황, 금, 녹염동광, 공작석, 회청 등의 무기안료와 먹 등의 유기염료를 사용하여 다채로운 색을 구현한 것으로 확인되었다. 바탕화면은 조선시대 불화의 재료로 흔치 않은 초(綃)를 사용한 것으로 확인되었다. 또한 백색 채색층은 여러 종류의 백색계열의 안료를 사용한 형태로 이는 괘불탱 백색 채색으로는 드문 사례라 할 수 있다.

생식생장기 냉수온이 벼의 Source와 Sink관련형질 및 양분흡수에 미치는 연구 II. 냉수관계가 벼의 엽신, 지경, 영각의 무기성분 조성에 미치는 영향 (Studies on the Growth Characters and Nutrient Uptake Related to Source and Sink by Cool Water Temperature at Reproductive Growth Stage II. Influence of Cool Water Irrigation on the Inorganic Element Content of Leaf Blades, Rachis Branches and Chaff of Rice)

  • 최수일;황창주;이중호
    • 한국작물학회지
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    • 제31권1호
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    • pp.1-8
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    • 1986
  • 냉수관계일수가 엽신, 지경, 영곡의 무기성분조성에 미치는 영향을 조사분석하였던바 다음과 같은 결과를 얻었다. 1. 엽신, 지경, 영각의 무기성분조성은 냉수관계일수가 길어질수록 전질소함량은 증가하나 인산, 가리, 규산함량조은 낮았으며 숙기별로는 전질소와 인산은 출수기 가리는 엽신과 지경에서는 출수기, 영각은 성숙기, 규산은 성숙기에 많았고 지경의 무기성분함량은 엽신보다는 영각과 유사한 양식을 나타냈다. 2. 냉수에 의해 도체가 저질소흡수과정장해를 받으면 인산, 가리, 규산도 흡수장해를 받으며 그 경향은 지경보다는 엽신과 영각의 영양장해가 현저하였으며 도체에 전질소함량이 높고 규산함량이 낮으면 지경과 영화의 퇴화 및 불임이 증가되고 지경의 영양장해가 엽신과 영각보다 퇴화 및 불임에 밀접하게 관여하였다.

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Performance of Fixing Agents in Controlling Micro-Stickies in Recycled Newsprint Pulp

  • Wang, Li-Jun;Chen, Fu-Shan;Zhou, Lin-Jie
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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    • pp.111-116
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    • 2006
  • The microstickes control effects of some fixing agents, including an inorganic PAC, an organic polyamine (PA) and polydiallydimethyl ammonium chloride (Pdadmac), and a high cationic starch (HCS), were investigated, together with their effects on wet end performances and physical properties of handsheets. Despite that the HCS and Pdadmac had lower cationic charge densities than the PA and PAC (the HCS being even lower), they gave higher zeta potentials to fibers, and lower turbidities, cationic demands and residual COD contents to the pulp liquid phases than the PA and PAC did. In all cases, the HCS showed even better effects than the Pdadmac. In addition, drainage speed was also much higher by the HCS treatments although paper formation was worsened. All the phenomena showed that the HCS can fix more dissolved and colloidal substances to cellulose fibers, indicating that the HCS functioned mainly with flocculation and even hydrogen bonding mechanisms. Data on optical properties further indicated that the HCS interacted preferentially with colloidal substances, since it fixed more 'dirty' microstickes to fibers which decreased more sheet brightness while increasing more sheet opacity (with both higher light absorption and scattering coefficients). Interestingly, the organic fixing agents did not decrease tensile, tearing, and folding strengths of paper sheets made from 100% recycled newsprint pulp, except when they were dosed in high amounts. On the contrary, the inorganic PAC had more serious negative effects on the strength properties, especially on folding endurance. The study suggested that proper use of the HCS can lead to better microstickies control effects than traditional agents and methods.

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Micronutrients Are Not Deficient in Children with Nonorganic Failure to Thrive

  • Hong, Junho;Park, Sowon;Kang, Yunkoo;Koh, Hong;Kim, Seung
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제22권2호
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    • pp.181-188
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    • 2019
  • Purpose: Inadequate calorie intake is one of the most important causes of nonorganic failure to thrive (NOFTT) and is thought to lead to multiple micronutrient deficiencies. However, there have been few studies on NOFTT and micronutrients. The aim of this study was to evaluate the micronutrient status of children with NOFTT. Methods: We conducted a retrospective cohort study in 161 children (106 with NOFTT and 55 health controls) at a single institution. Data on weight for age, height for age, body mass index, and biochemical parameters, indicating the children's nutritional and micronutrient status were reviewed via electronic medical records, and the two groups were compared. Results: Except inorganic phosphate levels, no statistically significant differences were seen in the laboratory findings indicating the children's nutritional and micronutrient status; notably, the inorganic phosphate levels were within the normal range in both groups. We then compared the severe NOFTT (weight for age below the first percentile) and control groups; however, no statistically significant differences were seen for any of the measured parameters. Conclusion: Most children with NOFTT in this study had normal micronutrient levels and other laboratory findings. Therefore, element deficiencies should not be considered a natural consequence of NOFTT or in healthy children. Close monitoring and additional evaluations are needed.

기름/물 분리를 위한 제올라이트 기반의 세라믹 분리막에 대한 총설 (A Review on Zeolite-based Ceramic Membrane for Oil/Water Separation)

  • 이주엽;라즈쿠마 파텔;김종학
    • 멤브레인
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    • 제32권2호
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    • pp.83-90
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    • 2022
  • 정유소와 석유 공장에서 발생하는 폐수는 심각한 환경오염으로 이어진다. 기름이 있는 물을 정수 처리하는 데에는 많은 방법이 존재하지만, 가장 효과적인 방법은 막을 이용한 기술이다. 물에서 기름기를 제거하는 데 사용되는 유기재료로 만들어진 고분자 막은 파울링이라는 고질적인 문제를 가지고 있다. 무기성 막은 수명이 길다는 점에서 유기성 분리막보다 효율적이다. 제올라이트 막은 우수한 화학적 안정성을 갖고 있으며 오랜 기간 재활용할 수 있다. 막에서 친수성의 존재는 막의 수 투과량을 증가시킨다. 제올라이트로 만들어진 세라믹 분리막은 물과 기름을 분리하는 데 사용되는 효율적인 무기막 중 하나이다. 본 리뷰논문은 i) 순수 제올라이트 막과 ii) 다른 물질과 혼합된 제올라이트 복합막, 2가지로 분류되는 제올라이트 기반의 무기막을 사용하는 물과 기름 분리 기술을 중점으로 다루고 있다.

유통중인 건미역(Undaria pinnatifida)의 미생물학적·이화학적 위해요소 분석 및 안전성 평가 (Risk Analysis and Safety Assessment of Microbiological and Chemical Hazards in the Dried Sea Mustard Undaria pinnatifida Distributed in Markets)

  • 전은비;김지윤;송민규;김진수;허민수;이정석;박신영
    • 한국수산과학회지
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    • 제54권6호
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    • pp.904-911
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    • 2021
  • For the safety assessment of microbiological and chemical hazards in dried sea mustard, fifteen samples of dried sea mustards Undaria pinnatifida were purchased from the supermarkets distributed throughout Korea. The contamination levels of total viable bacteria, coliforms, Escherichia coli, and nine pathogenic bacteria [Staphylococcus aureus, Salmonella spp., Listeria monocytogenes, Bacillus cereus, Vibrio spp., Clostridium perfringens, Enterohemorrhagic Escherichia coli (EHEC), Yersinia enterocolitica and Campylobacter jejuni/coli] were quantitatively or qualitatively assessed. Also, the heavy metals (lead, cadmium, total mercury, and inorganic arsenic), and radioactivity (131I, 134CS+137CS) were quantitatively assessed. This microbial and chemical analysis was performed using standard methods in Korean food code. The total viable bacteria ranged from 4.3×102 (5.0×10-1.5×103) CFU/g. Coliforms and E. coli were not detected in all samples (ND, <1 log10 CFU/g). All nine pathogenic bacteria were qualitatively detected as negative. The contamination levels of lead, cadmium, total mercury, and inorganic arsenic were 0.036 (0.015-0.051), 0.117 (0.088-0.156), 0.030 (0.017-0.048), and 0.058 (0.056-0.064) mg/kg, respectively. Radioactivity was also not detected in any sample. The microbial contamination levels determined in the current study may be potentially used as basis for performing microbial risk assessments of dried sea mustards.

열처리 공정에서 발생하는 무기·유기물질류의 함량특성 (Total content characteristics of inorganic and organic substances from wastes from thermal processes)

  • 연진모;김우일;강영렬;전태완;정성경;조윤아;김민선;신선경;오길종
    • 분석과학
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    • 제27권5호
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    • pp.254-260
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    • 2014
  • 본 연구에서는 열처리 공정에서 발생하는 폐기물 중 무기물질류 15 종과, 유기물질류 24 종 (PCDD/PCDFs, PAHs)에 대한 배출 특성을 파악하고자 수행하였다. 납 열적 야금에서 발생하는 폐기물 (EWC 10 04)에서 규제 무기금속물질류 중 Pb은 가장 높은 농도를 보였다. 이는 EWC 10 04에서 분진으로 인한 결과로 판단된다. 아연 열적 야금에서 발생하는 폐기물(EWC 10 05)에서 규제 무기금속물질류 중 Zn이 높은 농도로 나타나 EWC 10 05에서 분진으로 인한 결과로 판단되며, 또한 구리 열적 야금에서 발생하는 폐기물(EWC 10 06)에서 Cu가 65,177 mg/kg으로 규제기준 (100 mg/kg)보다 651 배 높게 나타난 것은 EWC 10 06에서 분진으로 인한 결과로 판단된다. 분진은 다이옥신 0.0005~11.748 ng-TEQ/g으로 검출되었고, 소각재는 0.0027 ng-TEQ/g로 나타났다. 다이옥신의 규제기준을 초과하는 시료는 없는 것으로 조사되었다. PAHs의 함량은 Naphthalene는 ND~118.9 mg/kg, Phenanthrene는 ND~9.6 mg/kg, Benzo[b]fluoranthene은 ND~48.4 mg/kg, Benzo[a]pyrene는 ND~62.6 mg/kg, Fluoranthene는 ND~10.7 mg/kg, Benzo[a]anthracene는 ND~11.5 mg/kg의 범위로 나타났다.