82 research outputs found
INFRARED SPECTRA OF AND
No full text D.E. Tolliver, G.A. Kyrala, and W.H. Wing, Phys. Rev. Lett. 43, 1719 (1979) P. Bernath and T. Amano, Phys. Rev. Lett. 48, 20 (1982)Author Institution: Department of Chemistry and Department of Astronomy and Astrophysics, The University of ChicagoWe have extended the earlier on the infrared spectrum of , by observing the hot band of and fundamental bands of isotopic species , , and . A difference frequency laser system and a diode laser have been used as tunable infrared sources and the ion velocity modulation technique was used for detection. A sealed off discharge tube was used to conserve . Six to fourteen vibration-rotation lines have been measured for each band. An analysis of the lines gave the following values for the band origins. [FIGURE] All of the molecular constants agreed remarkably well with the results of ab initio calculations. The rotational constants of the four isotopes were used to determine the isotopically independent parameters , and the . The observed variation of line intensities as a function of the mixing ratio is discussed in terms of simple ion-molecule reaction kinetics
MEASUREMENT OF THE PURE ROTATIONAL QUASIBOUND SPECTRA OF AND IN A LABORATORY PLASMA BY DIRECT LASER ABSORPTION
No full textAuthor Institution: Department of Chemistry, University of CambridgeThe pure rotational quasibound spectra of and have been observed in the mid infrared region using diode laser velocity modulation absorption spectroscopy. Four quasibound to quasibound and three bound to quasibound transitions of and one bound to quasibound transition of have been detected in a low pressure ac glow discharge. The highest quasibound level involved in the spectra is above the dissociation limit. The measured transition frequencies are in very good agreement with ab intio calculations. Two of the transitions have wider linewidths due to lifetime broadening
THE RADIAL HAMILTONIAN OPERATOR OF
No full textAuthor Institution: Department of Chemistry, Dalhousie University; Department of Chemistry, University of British ColumbiaExperimental line positions for , and have been employed in the determination of an effective non-adiabatic radial Hamiltonian operator for the ground electronic state in compact analytic form. The procedure considers a Born-Oppenheimer potential and isotopically invariant Born-Oppenheimer breakdown functions for each atomic centre. The nuclear mass-independent potential is represented by the modified Morse where a Pad\'{e} approximant is adopted for . The spectroscopic data base, which samples the entire potential well, includes a number of transitions from quasibound levels. The experimental line positions are reproduced to within their experimental uncertainties and calculated quasibound level widths are in excellent agreement with experimental measurements. Results are compared to recent ab initio calculations. . J.A. Coxon and P.G. Hajigeorgiou, J. Mol. Spectrosc. 150, 1 (1991)
Dissociation and ionization of in sub-cycle-controlled intense two-color fields
No full textUsing quantum-mechanical, one-dimensional, non-Born-Oppenheimer simulations we study the control over the strong-field dynamics of the helium hydride molecular ion HeH+ due to interaction driven by short and strong two-color laser pulses. We calculate yields of two competing fragmentation channels: electron removal and dissociation. We find that by changing the relative phase of the two colors, we can select the dominating channel. Nuclear motion is decisive for explaining ionization in this target. Ionization yields are vastly underestimated when nuclear motion is excluded and they are substantially reduced in the heavier isotopologue HeD+. Coupling of the two lowest electronic states is crucial even for the ground-state dissociation process. © 2020 The Author(s). Published by IOP Publishing Ltd
SPECTROSCOPY OF HELIUM HYDRIDE
No full textAuthor Institution: Max-Planck-Institut f\""ur QuantenoptikDiscrete spectra of HeH were observed after neutralization of a fast ion beam. A careful determination of Doppler shifts and Doppler broadenings allowed to determine line positions and line broadenings with an accuracy of 0.1 {\AA}. Accurate molecular constants for the band near 8000 {\AA} were obtained for four isotopic mixtures and are compared with recent ab inition calculations. Isotope effects are discussed. The linewidth of the band near 8000 {\AA} shows that the state of HeH predissociates with a lifetime of about 4 ps. The observed intensities of the lines can only be explained if an rotational excitation of of several thousand K is assumed. A first analysis of further bands of HeH in the visible region indicates, that the electronic structure of HeH is very similar to that of the Li atom
Effects of Helicopter Dynamics on Autorotation Transfer of Training
No full textThis paper analyzes the effects of the helicopter dynamics on pilots’ learning process and transfer of learned skills during autorotation training. A quasi-transfer-of-training experiment was performed with 14 experienced helicopter pilots in a moving-base flight simulator. Two types of helicopter dynamics, characterized by a different autorotative index, were considered: “hard,” with high pilot compensation required, and “easy,” with low compensation required. Two groups of pilots tested the two types of dynamics in a different training sequence: hard-easy-hard (HEH group) and easy-hard-easy (EHE group). Participants of both groups were able to attain adequate performance at touchdown in most of the landings with both types of dynamics. However, a clear positive transfer effect in terms of acquired skills is found in both groups from the hard to the easy dynamics, but not from the easy to the hard dynamics, confirming previous experimental evidence. Positive transfer is especially observed for the rate of descent at touchdown. The two groups differed in the control strategy applied, with the HEH group having developed a more robust control technique. During the last training phase the EHE group aligned its control strategy with that of the HEH group.Control & Simulatio
Extraction of Rare Earth Sulfates Using Saponified HEH (EHP) with Mg2+ Ion as Barrier Agent
No full textAs one kind of the most important intermediate materials in rare earth (RE) industry, RE sulfates have been considered difficult to be extracted and separated directly by saponified extractants due to the dissolubility of RE double sulfate of cation. By introducing a barrier agent such as Mg2+ ion in the present work, we proposed and developed a process to extract RE cations in sulfate medium with saponified HEH(EHP). Further, a selection criterion of the barrier agent was discussed. The results have revealed that the natural distribution of the univalent ion , RE3+ and Mg2+ ions, as determined by their extraction sequence in the cascade, hinders the contact between cation and RE ions, and thereby RE double sulfate precipitate does not form during the extraction. Consequently, the study can provide us a strong possibility for extracting and even separating RE using saponified extractants directly from sulfate solution in no need of any transformation of the RE salts employed.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000319040500017&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Chemistry, MultidisciplinaryEngineering, ChemicalSCI(E)EI1ARTICLE101572-15764
The Critique of Sao-fa by Heh Yie Suen
No full text[[abstract]] 賀貽孫的《騷筏》主要評論屈原及宋玉的作品，與他的另一詩學著作《詩筏》相互發明，實為研究賀氏文學理念與晚明文學批評的重要資料。惜國內對《騷筏》的詳細論評始終闕如，僅內地有零星論文略略提及，亟待學者研究補充。故本文擬細讀《騷筏》，歸納其批評觀點，闡發其文學理念，並以己意略作評論。論述的重點將包括：一、《騷筏》的批評體制；二、《騷筏》所呈顯的批評觀念，區分：「作品與作品」、「作品與作者」及「作品與讀者」等層面略加探討。間並引《詩筏》及賀氏其他著作之論述互證，略申其與晚明竟陵派的文學淵源，期對賀貽孫的文學理念及其時代意義能有更完整的理解。
Sao-fa (騷筏) of Heh Yie Suen (賀貽孫 1605-1688, an important poem critic in the transition between Ming and Qing) mainly criticized the works of Ch'ü Yüan (屈原) and Song Yuh (宋玉). It was done at the same time as his other work Shi-fa(詩筏). Sao-fa and Shi-fa are truly the important materials for studying Heh's literary ideology and the late-Ming Dynasty's literary criticism. However, it is incomprehensible that in Taiwan we do not see any detailed critique about Sao-fa. It has merely been referred to in a few papers. This book really awaits scholars to study and ameliorate. Therefore, this paper will closely study Sao-fa and conclude its points of criticism in order to manifest its literary ideology. At the same time, by including my personal points of view, I will comment a bit abut Sao-fa and its author. In the description the focuses are 1) Sao-fa's style of criticism; 2) the literary critical points shown in Sao-fa, which are divided into three levels: work and work, work and the author, the author and the readers. The three above-mentioned levels are discussed briefly. Throughout the paper Shi-fa and Heh's other works are also used to reflect on Sao-fa as a way to refer to Heh's literary history with Late-ming Dynasty's Jing-ling School (竟陵派). Hopefully this paper will give the readers a more complete understanding to Heh's literary ideology and his importance in the history, and I am sure that Sao-fa is critical to an understanding of the development of literary criticism and theory of Ming Dynasty
CHARACTER AND IMAGE RECOGNITION FOR DATA CATALOGING IN ECOLOGICAL RESEARCH
No full textData collection is an essential, but manpower intensive procedure in ecological research. An algorithm was developed by the author which incorporated two important computer vision techniques to automate data cataloging for butterfly measurements. Optical Character Recognition is used for character recognition and Contour Detection is used for imageprocessing. Proper pre-processing is first done on the images to improve accuracy. Although there are limitations to Tesseract’s detection of certain fonts, overall, it can successfully identify words of basic fonts. Contour detection is an advanced technique that can be utilized to measure an image. Shapes and mathematical calculations are crucial in determining the precise location of the points on which to draw the body and forewing lines of the butterfly. Overall, 92% accuracy were achieved by the program for the set of butterflies measured
Europe’s Journey to Modernity: Developing the House of European History in Brussels
No full textThis thesis investigates the historiographical and museological aspects of the House of European History (HEH). This new museum was developed by the European Parliament in Brussels between 2007 and 2017, being conceived as an additional contribution to the European Union’s identity, integration and communication agendas. It is partially ethnographic in nature and focuses on the development process of the HEH during its conceptualization and production phase, from March 2011 to May 2017. During this period the author was an integral part of the Academic Project Team, which was charged with creating the HEH. In seeking to address the central question – What is the House of European History as a museological act? – the thesis examines the nexus between history, memory and political power, from which a distinctive, new type of historical museum emerged in Germany that emphasised the importance of people’s living memory. Drawing upon the German House of History concept and the methodology offered by conceptual history, this study highlights how a contemporary museum can be developed as a concrete and symbolic manifestation of political power. The production of this new historical museum in the political capital of Europe was born through political ambition, rooted in European history politics, influenced by the vagaries of Parliamentary bureaucracy and dependent for its form and content upon a micro-network of non-governmental actors drawn from European museum scene
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