Molecular Structure Investigations by Electron Diffraction Method IV. The Molecular Structures of α, γ-Dichlorohydrin and Ethylene Cyanohydrin

the underlying structure of language proficiency and the proficiency level

هدف از انجام این تخقیق بررسی رابطه احتمالی بین سطح مهارت زبان خارجی (foreign language proficiency) و ساختار مهارت زبان خارجی بود. تعداد 314 زبان آموز مونث و مذکر که عمدتا دانشجویان رشته های زبان انگلیسی در سطوح کارشناسی و کارشناسی ارشد بودند در این تحقیق شرکت کردند. از لحاظ سطح مهارت زبان خارجی شرکت کنندگان بسیار با هم متفاوت بودند، (75 نفر سطح پیشرفته، 113 نفر سطح متوسط، 126 سطح مقدماتی). کلا ...

Comparison of Molecular Structures Determined by Electron Diffraction and Spectroscopy. Ethane and Diborane

Gas-phase average structures for the ground-vibrational state (1',) for ethane and diborane have been determined by a critical comparison of the experimental results obtained from electron diffraction (average internuclear distances ra) and those obtained from high-resolution infrared and Raman spectroscopy (rotational constants B.("'»). Experimental values have been taken from the recent liter...

Femtosecond electron diffraction: 'making the molecular movie'.

Femtosecond electron diffraction (FED) has the potential to directly observe transition state processes. The relevant motions for this barrier-crossing event occur on the hundred femtosecond time-scale. Recent advances in the development of high-flux electron pulse sources with the required time resolution and sensitivity to capture barrier-crossing processes are described in the context of att...

Excited state molecular structures and reactions directly determined by ultrafast electron diffraction.

In this communication, we report on the use of ultrafast electron diffraction to determine structural dynamics of excited states and reaction products of isolated aromatic carbonyls, acetophenone and benzaldehyde. For a 266 nm excitation, a bifurcation of pathways is structurally resolved, one leading to the formation of the triplet state (quinoid structure) and another to chemical products: fo...

The Molecular Structure of Nitrogen Dioxide. A Reinvestigation by Electron Diffraction