http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Radiation Cross-linked Carboxymethylated Starch and Iron Removal Capacity in Aqueous Solution
Bhoj Raj Pant,전혜진,송현훈 한국고분자학회 2011 Macromolecular Research Vol.19 No.3
Cross-linked carboxymethylated starch derivatives were synthesized and tested for their iron adsorbing capacity in aqueous solutions. To obtain the highly substituted carboxymethyl starch (CMS), a multi-step carboxymethylation process was adopted. The CMS with DS = 0.92 in aqueous medium was then exposed to electron beam radiation (EB) at various doses to yield the cross-linked carboxymethyl starch (CCMS). The CCMS of maximum gel content (87.1%) was obtained at 50 kGy with a 50% (w/v) aqueous CMS solution. The iron removal capacity of the CCMS was almost independent of the pH of the metal solution in the acidic range (pH 3-5), where the physical entrapment of the ion is dominant over a chelation reaction. The high physical entrapment was apparently associated with the high cross-link density. The adsorption capacity improved when the pH approached neutral but the iron showed complete precipitation at pH 7.
Gautam, Bhoj R.,Lee, Changyeon,Younts, Robert,Lee, Wonho,Danilov, Evgeny,Kim, Bumjoon J.,Gundogdu, Kenan American Chemical Society 2015 ACS APPLIED MATERIALS & INTERFACES Vol.7 No.50
<P>All-polymer solar cells exhibit rapid progress in power conversion efficiency (PCE) from 2 to 7.7% over the past few years. While this improvement is primarily attributed to efficient charge transport and balanced mobility between the carriers, not much is known about the charge generation dynamics in these systems. Here we measured exciton relaxation and charge separation dynamics using ultrafast spectroscopy in polymer/polymer blends with different molecular packing and morphology. These measurements indicate that preferential face-on configuration with intermixed nanomorphology increases the charge generation efficiency. In fact, there is a direct quantitative correlation between the free charge population in the ultrafast time scales and the external quantum efficiency, suggesting not only the transport but also charge generation is key for the design of high performance all polymer solar cells.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2015/aamick.2015.7.issue-50/acsami.5b08531/production/images/medium/am-2015-08531f_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am5b08531'>ACS Electronic Supporting Info</A></P>
Sailendra Dewan,Iswar Kumar Chettri,Kishor Sharma,Bhoj Kumar Acharya 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.2
The lowland areas of the Himalayan region are subjected to immense anthropogenic pressure because of least representation in the protected area network. Kitam Bird Sanctuary is the only representative protected area that occurs below 1000 m in Sikkim state of India (a part of globally significant biodiversity hotspot of Himalayas) and serves as the refuge for various species of flora and fauna. Here we studied butterfly diversity and community composition in Kitam Bird Sanctuary (a small protected area of 6 km 2 geographical area) following point count method spread across predetermined transects. Altogether 1674 butterflies belonging to 111 species and six families were recorded after completion of 240 point counts. Among these, 18 species are federally protected under the Wildlife (Protection) Act (1972) of India. Most of the butterflies were forest specialist in terms of habitat preference, whereas based on host plant specificity, the butterfly community was mostly dominated by generalist feeder (Oligophagous II and Polyphagous). Butterfly community parameters showed a strong correlation with habitat variables. While Kitam Bird Sanctuary is primarily designated for conservation of lowland birds, the high diversity of butterflies both in terms of taxonomic richness and trait composition suggests that the sanctuary harbors an ideal habitat for butterflies of the tropical region and invites conservation attention.
김선하,김영권,( Mohammad Afsar Uddin ),( Robert Younts ),이원호,( Bhoj Gautam ),최준형,( Cheng Wang ),( Kenan Gundogdu ),김범준,우한영 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.1
Tuning the chemical structures of conjugated polymers by fluorination is a simple, yet powerful strategy for regulating their energy level and blend morphology between donor and acceptor. Herein, we investigate the effect of fluorination to P(NDI2OD-T2), the most generally used as acceptors in all-polymer solar cells (all-PSCs), on their photovoltaic properties. We developed all-PSCs based on PBDTTTPD as donor and P(NDI2OD-T2F) as acceptors, and examined their charge generation and recombination behaviors by TAS. These systems exhibit faster hole transports and longer polaron life time, and subsequently the high power conversion efficiency of 6.09%, compared with control devices using P(NDI2OD-T2) as acceptors (2.02%). Furthermore, higher miscibility of P(NDI2OD-T2F) with donors in blend films was also examined by AFM and R-SoXS. Therefore, we concluded that fluorination is effective strategy for high efficient all-PSCs due to deepening energy level and producing miscible morphology.