http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : hring, Steffen (검색결과 3 건)
- 무료
- 기관 내 무료
- 유료
-
Bill, Nathan L.,Ishida, Masatoshi,Bä,hring, Steffen,Lim, Jong Min,Lee, Sangsu,Davis, Christina M.,Lynch, Vincent M.,Nielsen, Kent A.,Jeppesen, Jan O.,Ohkubo, Kei,Fukuzumi, Shunichi,Kim, Dongho,S American Chemical Society 2013 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.135 No.29
<P>A new class of redox-active free base and metalloporphyrins fused with the 1,3-dithiol-2-ylidene subunits present in tetrathiafulvalene, termed MTTFP (M = H<SUB>2</SUB>, Cu, Ni, Zn), have been prepared and characterized. The strong electron-donating properties of MTTFP were probed by electrochemical measurement and demonstrated that oxidation potentials can be tuned by metalation of the free base form, H<SUB>2</SUB>TTFP. X-ray crystal structures of H<SUB>2</SUB>TTFP, ZnTTFP, and CuTTFP revealed that a severe saddle-shape distortion was observed with the dithiole rings bent out of the plane toward one another in the neutral form. In contrast, the structure of the two-electron oxidized species (CuTFFP<SUP>2+</SUP>) is planar, corresponding to a change from a nonaromatic to aromatic structure upon oxidation. A relatively large two-photon absorption (TPA) cross-section value of H<SUB>2</SUB>TTFP<SUP>2+</SUP> (1200 GM) was obtained for the free base compound, a value that is much higher than those typically seen for porphyrins (<100 GM). Augmented TPA values for the metal complexes were also seen. The strong electron-donating ability of ZnTTFP was further enhanced by binding of Cl<SUP>–</SUP> and Br<SUP>–</SUP> as revealed by thermal electron-transfer between ZnTTFP and Li<SUP>+</SUP>-encapsulated C<SUB>60</SUB> (Li<SUP>+</SUP>@C<SUB>60</SUB>) in benzonitrile, which was “switched on” by the addition of either Cl<SUP>–</SUP> or Br<SUP>–</SUP> (as the tetrabutylammonium salts). The X-ray crystal structure of Cl<SUP>–</SUP>-bound ZnTTFP was determined and provided support for the strong binding between the Cl<SUP>–</SUP> anion and the Zn<SUP>2+</SUP> cation present in ZnTTFP.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2013/jacsat.2013.135.issue-29/ja404830y/production/images/medium/ja-2013-04830y_0015.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja404830y'>ACS Electronic Supporting Info</A></P>
-
Bill, Nathan L.,Lim, Jong Min,Davis, Christina M.,Bä,hring, Steffen,Jeppesen, Jan O.,Kim, Dongho,Sessler, Jonathan L. The Royal Society of Chemistry 2014 Chemical communications Vol.50 No.51
<P>A π-extended tetrathiafulvalene-boradiazaindacene chimera, ex-TTF-BODIPY, has been prepared. The resulting system undergoes sequential one-electron oxidations, allowing access to both the mono-oxidized radical cationic and dicationic states. Additionally, ex-TTF-BODIPY displays electrochromic and electrofluorochromic behaviour in the near-IR portion of the electromagnetic spectrum and functions as a redox switched “on–off–on” emissive system.</P> <P>Graphic Abstract</P><P>Ex-TTF-BODIPY functions as a near-IR electrochromic and electrofluorochromic switch, displaying redox controlled “on–off–on” emission features. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c4cc02567a'> </P>
-
Refinement of temperature determination in cutting zones
Michael Storchak,Valerii Kushner,Hans-Christian Möhring,Thomas Stehle 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.8
A methodology for temperatures calculating in different cutting zones is proposed, taking the peculiarities of heat distribution for moving sources into account. For this, the correlation was established between the heat flow densities and temperatures in the chip forming area, in the stagnation zone as well as in the zone of plastic contact between the chip and the tool. The method for temperature calculation was based on the joint solution of the heat conduction equation and the constitutive equation of the machined material. A significant simplification of the temperature calculation was achieved without sacrificing accuracy by considering the features of the heat propagation from fast-moving sources. Taking into account material softening, the temperature and heat flow density distributions along the tool rake and clearance faces and in the stagnation zone were numerically calculated. The developed models were confirmed by experiment. The comparison showed good agreement between theoretical and experimental results.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
