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백년만에 디렘마에 빠진 교육 : 가장 가치있는 지식이란 무엇인가
Gross, Richard E. 이화여자대학교 사범대학 교육학과 1965 교육 연구 Vol.- No.26
1859년, 웨스트민스터 레뷰(Westminster Review)지는 허버트 스펜서(Herbert Spencer)의 예리한 논문, "가장 가치 있는 지식이란 무엇인가?"를 출판하였다. 이것은 교육의 구 개념과 스펜서의 주제인 교육의 진실한 목적은 "완전한 생활을 위하여 준비하는것"이어야만 한다는 것과의 사이에 세기를 끌어오는 오랜 논쟁을 벌리게 하였다.
Kim, Sung Kuk,Sessler, Jonathan L.,Gross, Dustin E.,Lee, Chang-Hee,Kim, Jong Seung,Lynch, Vincent M.,Delmau, Lætitia H.,Hay, Benjamin P. American Chemical Society 2010 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.132 No.16
<P>An ion-pair receptor, the calix[4]pyrrole-calix[4]arene pseudodimer <B>2</B>, bearing a strong anion-recognition site but not a weak cation-recognition site, has been synthesized and characterized by standard spectroscopic means and <I>via</I> single-crystal X-ray diffraction analysis. In 10% CD<SUB>3</SUB>OD in CDCl<SUB>3</SUB> (v/v), this new receptor binds neither the Cs<SUP>+</SUP> cation nor the F<SUP>−</SUP> anion when exposed to these species in the presence of other counterions; however, it forms a stable 1:1 solvent-separated CsF complex when exposed to these two ions in concert with one another in this same solvent mixture. In contrast to what is seen in the case of a previously reported crown ether “strapped” calixarene−calixpyrrole ion-pair receptor <B>1</B> (J. Am. Chem. Soc. 2008, 130, 13162−<lpage>13166</lpage>), where Cs<SUP>+</SUP> cation recognition takes place within the crown, in <B>2</B>·CsF cation recognition takes place within the receptor cavity itself, as inferred from both single-crystal X-ray diffraction analyses and <SUP>1</SUP>H NMR spectroscopic studies. This binding mode is supported by calculations carried out using the MMFF94 force field model. In 10% CD<SUB>3</SUB>OD in CDCl<SUB>3</SUB> (v/v), receptor <B>2</B> shows selectivity for CsF over the Cs<SUP>+</SUP> salts of Cl<SUP>−</SUP>, Br<SUP>−</SUP>, and NO<SUB>3</SUB><SUP>−</SUP> but will bind these other cesium salts in the absence of fluoride, both in solution and in the solid state. In the case of CsCl, an unprecedented 2:2 complex is observed in the solid state that is characterized by two different ion-pair binding modes. One of these consists of a contact ion pair with the cesium cation and chloride anion both being bound within the central binding pocket and in direct contact with one another. The other mode involves a chloride anion bound to the pyrrole NH protons of a calixpyrrole subunit and a cesium cation sandwiched between two cone shaped calix[4]pyrroles originating from separate receptor units. In contrast to what is seen for CsF and CsCl, single-crystal X-ray structural analyses and <SUP>1</SUP>H NMR spectroscopic studies reveal that receptor <B>2</B> forms a 1:1 complex with CsNO<SUB>3</SUB>, with the ions bound in the form of a contact ion pair. Thus, depending on the counteranion, receptor <B>2</B> is able to stabilize three different ion-pair binding modes with Cs<SUP>+</SUP>, namely solvent-bridged, contact, and host-separated.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2010/jacsat.2010.132.issue-16/ja100715e/production/images/medium/ja-2010-00715e_0014.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja100715e'>ACS Electronic Supporting Info</A></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja100715e'>ACS Electronic Supporting Info</A></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja100715e'>ACS Electronic Supporting Info</A></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja100715e'>ACS Electronic Supporting Info</A></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja100715e'>ACS Electronic Supporting Info</A></P>
Yoon, Dae-Wi,Gross, Dustin E.,Lynch, Vincent M.,Sessler, Jonathan L.,Hay, Benjamin P.,Lee, Chang-Hee WILEY-VCH Verlag 2008 Angewandte Chemie Vol.47 No.27
<B>Graphic Abstract</B> <P>Weak but important: The chloride anion binding properties of diametrically strapped calixpyrroles bearing benzene (see structure), pyrrole, and furan moieties in the strap have been studied in the solid state, in solution, and through theoretical analyses. The results obtained provide support for the notion that C&n.bond;H⋅⋅⋅Cl<SUP>−</SUP> hydrogen bonds are significant and contribute substantially to the Cl<SUP>−</SUP> binding energetics. <img src='wiley_img/14337851-2008-47-27-ANIE200801426-content.gif' alt='wiley_img/14337851-2008-47-27-ANIE200801426-content'> </P>
The nELBE Neutron Time of Flight Facility
A. R. Junghans,E. Altstadt,R. Beyer,E. Birgersson,T. Cowan,A. Ferrari,R. Hannaske,A. Matic,K. D. Schilling,R. Schlenk,S. Schneider,R. Schwengner,A. Wagner,F. -P. Weiss,D. Gehre,E. Grosse 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23
At the superconducting electron linear accelerator ELBE at Forschungszentrum Dresden-Rossendorf the neutron time-of-flight facility nELBE has become operational. Fast neutrons in the energy range from 200 keV to 10 MeV are produced by the pulsed electron beam from ELBE impinging on a liquid lead circuit as a radiator. The short beam pulses of 10 ps provide the basis for an excellent time resolution for neutron time-of-flight experiments, giving an energy resolution of about <1% at 1 MeV with a short flight path of 5 m. The neutron intensity on target is ∼4·10^4 n/(cm^2 s) using an electron bunch charge of 77 pC and 100 kHz pulse repetition rate. The energy range of the neutrons produced is well suited for neutron cross section measurements relevant for the development of Generation IV reactor systems and for the transmutation of nuclear waste. First measurements of inelastic neutron scattering cross sections have been performed and will be presented.