A large-area free-standing graphene oxide multilayer membrane with high stability for nanofiltration applications

Chen, Long,Li, Yanhui,Chen, Lina,Li, Na,Dong, Chenglong,Chen, Qiong,Liu, Beibei,Ai, Qing,Si, Pengchao,Feng, Jinkui,Zhang, Lin,Suhr, Jonghwan,Lou, Jun,Ci, Lijie Elsevier 2018 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.345 No.-

<P><B>Abstract</B></P> <P>A flexible and free-standing graphene oxide and nylon 6 (GO@nylon 6) multilayer nanofiltration membrane was prepared by a layer-by-layer assembly process. The combination of electrospinning and electrospraying technique was employed, which can facilely prepare large-area membrane with size of 20 × 30 cm. The mechanical stability of multilayer membrane has enhanced significantly due to the tightly locked structure achieved by nylon 6 nanofibers network. The novel GO@nylon 6–13 multilayer nanofiltration membrane demonstrated a pure water flux up to 11.15 L m<SUP>−2</SUP> h<SUP>−1</SUP> bar<SUP>−1</SUP>, while keeping high organic dye rejection rate (>95% for methylene blue, and >99% for methyl orange). The rejections rate of the Na<SUB>2</SUB>SO<SUB>4</SUB>, NaCl, CuSO<SUB>4</SUB>, and Pb(NO<SUB>3</SUB>)<SUB>2</SUB> were 56.5%, 27.6%, 36.7%, and 18.9%, respectively. Furthermore, GO@nylon 6–13 multilayer nanofiltration membrane also demonstrated a high flux of some common organic solvents (8.4, 5.3, and 0.8 L m<SUP>−2</SUP> h<SUP>−1</SUP> bar<SUP>−1</SUP> for methanol, ethanol, and NMP, respectively), showing excellent chemical stability for separation process in those solvents.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Large-area GO@nylon 6 multilayer nanofiltration membrane was prepared. </LI> <LI> The multilayer structure enhances the mechanical stability. </LI> <LI> The multilayer membrane demonstrates a high water flux. </LI> <LI> The multilayer membrane shows high rejection rate for organic dyes. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Photograph and cross-section SEM image of GO@nylon 6 multilayer nanofiltration membrane, the inset shows the water contact angle.</P> <P>[DISPLAY OMISSION]</P>

Pressure-induced semiconductor-to-metal phase transition of a charge-ordered indium halide perovskite

Lin, Jia,Chen, Hong,Gao, Yang,Cai, Yao,Jin, Jianbo,Etman, Ahmed S.,Kang, Joohoon,Lei, Teng,Lin, Zhenni,Folgueras, Maria C.,Quan, Li Na,Kong, Qiao,Sherburne, Matthew,Asta, Mark,Sun, Junliang,Toney, Mic National Academy of Sciences 2019 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.116 No.47

<P><B>Significance</B></P><P>Metal halide perovskites attract great interest for a wide range of applications due to their remarkable optoelectronic properties. The development of environmentally friendly halide perovskite materials with various crystal structures and compositions offers unprecedented opportunities to achieve desired properties and applications. In this work, we demonstrated an In-based, charge-ordered all-inorganic halide double perovskite with the composition of Cs<SUB>2</SUB>In(I)In(III)Cl<SUB>6</SUB> synthesized by solid-state reaction. High-pressure optical properties were studied, and a pressure-driven, fully reversible semiconductor–metal phase transition was discovered. This In-based charge-ordered structure may inspire new understanding of halide perovskite as well as provide a platform for future discovery of exotic electronic phenomena such as high-<I>T</I><SUB>C</SUB> superconductivity in halide perovskite compounds.</P><P>Phase transitions in halide perovskites triggered by external stimuli generate significantly different material properties, providing a great opportunity for broad applications. Here, we demonstrate an In-based, charge-ordered (In<SUP>+</SUP>/In<SUP>3+</SUP>) inorganic halide perovskite with the composition of Cs<SUB>2</SUB>In(I)In(III)Cl<SUB>6</SUB> in which a pressure-driven semiconductor-to-metal phase transition exists. The single crystals, synthesized via a solid-state reaction method, crystallize in a distorted perovskite structure with space group <I>I</I>4/<I>m</I> with <I>a</I> = 17.2604(12) Å, <I>c</I> = 11.0113(16) Å if both the strong reflections and superstructures are considered. The supercell was further confirmed by rotation electron diffraction measurement. The pressure-induced semiconductor-to-metal phase transition was demonstrated by high-pressure Raman and absorbance spectroscopies and was consistent with theoretical modeling. This type of charge-ordered inorganic halide perovskite with a pressure-induced semiconductor-to-metal phase transition may inspire a range of potential applications.</P>

Korea's International Tax Treaties

NA, SEONG LIN,Kim, Wan Soon 고려대학교 경영대학 1992 경영논총 Vol.36 No.1

The Sustainability of Government Debt in Korea

Na Seong-Lin(나성린),Park Ki-Baeg(박기백),Park Hyung-Soo(박형수) 한국재정학회(구 한국재정·공공경제학회) 2007 공공경제 Vol.12 No.2

  본 연구는 논란이 되고 있는 정부부채의 안정성을 검증하기 위하여 3가지 분석을 실시하였다. Bohn"s test에 따르면 우리나라는 정부부채에 적절히 반응하므로 재정안정성이 있는 것으로 나타났다. 지출 전망을 이용하여 재정안정에 필요한 세입 증대 수준(Tax gap)을 계산한 결과를 보면 단기나 중기는 문제가 없다. 그러나 장기적으로는 연금재정 악화, 복지지출 증대로 세입 증대가 불가피한 것으로 나타나고 있다. 경제수준이나 정치적 요인 등을 감안하여 부채수준을 국제비교한 지수(IGDC index)를 보면 우리나라는 외국보다 부채 수준이 낮지만 최근 증가하는 추세를 보이고 있다.<BR>  따라서 공적연금의 잠재적인 부채, 경제성장의 정체, 고령화 및 저출산 등의 재정 여건을 감안하면, 장기적인 재정안정성을 확보하기 위하여 공적연금의 개혁이 필수적이고, 정부는 우리나라의 부채수준 증가에 더욱 더 조심하여야 한다.   We carried out three different tests to check the sustainability of government debt in Korea: Bohn"s test, tax gap test and IGDC index. We find some consistency in the result for all three tests. Namely, the government debt in Korea seems to be sustainable in the short or medium term, but may not be sustainable in the long term.<BR>  In particular, considering huge potential deficit in public pension system and rapid slowdown in future growth rate together with rapid aging and low birth rate, Korean government needs to pay special attention to the pace of government debt level in Korea.

Game Theory in Public Choice : A Critical Survey of Themes

(Na Seong Lin) 한양대학교 경제연구소 1997 JOURNAL OF ECONOMIC RESEARCH Vol.2 No.1

蒙古国与朝鲜半岛

娜琳(Na Lin) 단국대학교 몽골연구소 2017 몽골지역연구 Vol.2 No.2

This paper expounds the particularity and importance of the strategic position of Mongolia, North Korea and South Korea. From the political, economic and cultural perspective discusses the close relationship of Mongolia and South Korea, North Korea’s. Looking forward to Mongolia’s mediation of the Korean Peninsula issue base on the good relations of Mongolia and South & North koreas. It will relaxation of the situation on the korea peninsula will have a positive impact. At the same time, for China’s adherence to the policy of peace and stability, denuclearization and the Korean Peninsula through dialogue and consultation is undoubtedly positive support.

Impact of Hypertension on Cognitive Decline and Dementia

Han Lin Naing,Shyh Poh Teo 대한노인병학회 2020 Annals of geriatric medicine and research Vol.24 No.1

Dementia reduces a person’s ability to perform their activities of daily living and is the leading cause of morbidity worldwide. While most preventive measures are ineffective in reducing dementia risk, active treatment of hypertension in middle-aged and older adults without dementia may reduce the incidence of dementia. Hypertension is associated with vascular dementia but may also affect the manifestations of Alzheimer disease. Observational studies support the association between hypertension and white matter lesions, hippocampal atrophy, and cognitive decline. Both increased and decreased blood pressure were related to the development of white matter lesions. Cohort studies showed that hypertension treatment and treatment duration were associated with lower cognitive decline. This study describes findings from randomized controlled studies on the effects of antihypertensives on cognitive decline. Only the Systolic Hypertension in Europe (Syst-Eur) trial using calcium-channel blockers demonstrated a significant reduction in dementia incidence. Further studies are required to evaluate the long-term benefits of antihypertensive treatment in dementia.

Add-on Tiotropium in Chinese Patients With Moderate Asthma: A Pooled Subgroup Analysis of MezzoTinA-Asthma 1 and 2

Jiangtao Lin,Huanying Wan,Jian Kang,Qianli Ma,Ping Chen,Meiling Jin,Haoyan Wang,Shuang Liu,Qinglin Hao,Yong Lin,Lin Su,Na Hu 대한천식알레르기학회 2019 Allergy, Asthma & Immunology Research Vol.11 No.4

Purpose: Asthma affects approximately 30 million patients in China; however, tiotropium data for Chinese patients is limited. This study aimed to assess the efficacy and safety of tiotropium in Chinese patients with moderate symptomatic asthma. Methods: A post hoc subgroup analysis was conducted on 430 Chinese patients pooled from two 24-week, replicate phase 3 trials (NCT01172808 and NCT01172821), in which they received once-daily tiotropium 2.5 μg (Tio R2.5) or 5 μg (Tio R5) (n = 106 or 109, respectively), twice-daily salmeterol 50 μg (Sal 50) (n = 110), or placebo (n = 105), while maintaining inhaled corticosteroids (ICS). The co-primary endpoints assessed in week 24 were forced expiratory volume in 1 second (FEV1) peak0–3h response, trough FEV1 response, and responder rate as assessed using the Asthma Control Questionnaire (ACQ). Results: For both FEV1 peak0–3h responses and trough FEV1 responses, the mean treatment differences were greater for Tio R2.5, Tio R5, and Sal 50 compared with placebo at 0.249 L, 0.234 L, and 0.284 L, and 0.172 L, 0.180 L, and 0.164 L, respectively (P< 0.001). The ACQ responder rate in placebo, Tio R2.5, Tio R5, and Sal 50 was 58.7%, 62.3%, 59.3%, and 69.1%, respectively. Furthermore, 11 (2.6%) of 430 patients had serious adverse events (Tio R5, n = 4; Tio R2.5, n = 1; Sal 50, n = 1; and placebo, n = 5). Conclusions: Once-daily tiotropium, as add-on to medium-dose ICS, was effective and well tolerated for Chinese patients with moderate symptomatic asthma, consistent with the main analysis.

참여정부의 경제정책 평가와 과제 ; 참여정부 경제정책 일반 -성장과 분배의 조화-

나성린 ( Na Seong Lin ) 텔코경영연구원 2003 International Trade Business Institute Review Vol.9 No.1

소득 2만불 시대 달성을 위한 과제 ; 국정운영 방향의 전환

나성린 ( Na Seong Lin ) 텔코경영연구원 2003 International Trade Business Institute Review Vol.9 No.2