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Papers by Alain Berinstain

ACS Symposium Series, 1993

ABSTRACT

Space of Service to Humanity, 1997

The issues covered in the discussion included regulation, future strategies and techniques for co... more The issues covered in the discussion included regulation, future strategies and techniques for communication satellites, and applications of telecommunication services to humanitarian services.

Journal of Inorganic Biochemistry, 1991

Canada is in the process of negotiating contributions to international Mars exploration missions.... more Canada is in the process of negotiating contributions to international Mars exploration missions. The most important mission opportunities are NASA Mars Science Laboratory mission planned for 2009 and the NASA Scout mission planned for 2007. Advanced technology development is performed to position Canada for these and future opportunities. Examples of such technology development include subsurface sampling systems, robot manipulators, a sample processing station, lidar sensors and autonomous robotics algorithms.

Introduction: Canada has had a long involvement in space science beginning with the launch of the... more Introduction: Canada has had a long involvement in space science beginning with the launch of the Canadian satellite Alouette 1, in 1962. However the Canadian Space Agency's involvement in planetary exploration began only in the late 1990's with the contribution of the Thermal Plasma Analyzer (TPA) to the Japanese Nozomi mission. The Canadian Space Agency (CSA) is now contributing science payloads to the first NASA Scout mission, Phoenix, and NASA's Mars Science Laboratory, and is exploring strategies to integrate existing science and technology capabilities towards a robust planetary exploration program. Underpinning a Canadian exploration strategy, the Canadian Arctic forms a natural asset. Its cold, dry desert environments provide an operational analogue for Mars exploration, and its relatively unweathered impact craters, permafrost regions and arctic springs provide sites where processes relevant to Mars polar science can be studied. Current program elements: Three p...

Hipkin V. Osinski G. R. Berinstain A. Léveillé R. The Canadian Analogue Research Network (CARN): ... more Hipkin V. Osinski G. R. Berinstain A. Léveillé R. The Canadian Analogue Research Network (CARN): Opportunities for Terrestrial Analogue Studies in Canada and Abroad [#2052] We will present an overview of the Canadian Analogue Research Network (CARN), including a description of the various analogue sites in CARN, potential new sites, and a discussion regarding how CARN is applicable to the global exploration strategy.

Terrestrial analogues are places on Earth that approximate, in some respect, the geological, envi... more Terrestrial analogues are places on Earth that approximate, in some respect, the geological, environmental and putative biological conditions on a particular planetary body, either at the present-day or sometime in the past. Analogue studies are driven by the need to understand processes on Earth in order to interpret and groundtruth data sent back from Mars and other planetary bodies by unmanned orbiters and rovers. This presents an ideal opportunity to further collaboration between the solid earth and planetary science communities in Canada and elsewhere. Analogue environments also provide a critical locale for optimizing exploration requirements and strategies for future manned missions to the Moon and Mars. The ideal geography and climate, a wide diversity of analogues sites, and a history of analogue activities, ensures that Canada can play a leading role in the expanding international use of terrestrial analogues sites. SOMMAIRE Les analogues terrestres sont ces endroits sur l...

Advances in Space Research, Jul 15, 2009

Canada began research on space-relevant biological life support systems in the early 1990s. Since... more Canada began research on space-relevant biological life support systems in the early 1990s. Since that time Canadian capabilities have grown tremendously, placing Canada among the emerging leaders in biological life support systems. The rapid growth of Canadian expertise has been the result of several factors including a large and technically sophisticated greenhouse sector which successfully operates under challenging climatic conditions, well planned technology transfer strategies between the academic and ...

Can J Chem, 1995

The photochemistry of various mono- and dimethoxy-substituted α-bromoacetophenones has been inves... more The photochemistry of various mono- and dimethoxy-substituted α-bromoacetophenones has been investigated by laser flash photolysis in organic solvents. The short-lived excited singlet states cleave to yield bromine atoms and the corresponding methoxyphenacyl radicals with quantum yields ranging from 0.13 to 0.35. With the exception of 4-methoxy-α-bromoacetophenone (6), all other substrates yield readily detectable triplet states; these have π,π* character and are very poor hydrogen abstractors. Triplet decay does not contribute to methoxyphenacyl radical formation. While methoxyphenacyl radicals may have a spin density as high as 0.3 at the carbonyl oxygen, which accounts for the alkoxy-like visible band in their absorption spectrum, their chemical reactivity is dominated by the radical character at the carbon site. Methoxyphenacyl radicals are modest hydrogen abstractors; for example, reaction of 6 with 1,4-cyclohexadiene occurs with a rate constant of 2.6 × 105 M−1 s−1, while for addition to the double bond in 1,1-diphenylethylene the rate constant is 9.4 × 107 M−1 s−1. Additions to other double bonds are likely to be slower (e.g., 12 + 1,3-cyclohexadiene, k ≤ 105 M−1 s−1). In contrast, reaction with oxygen occurs with kq = 2.5 × 109 M−1 s−1. Under the conditions relevant for their participation in paper yellowing, the methoxyphenacyl radicals will be converted to peroxyl radicals. These probably play a key role in the oxidative photodegradation of lignin. Keywords: methoxyphenacyl radicals, α-bromoacetophenones, laser flash photolysis.

J Am Chem Soc, 1990

Page 1. J. Am. Chem. SOC. 1990, 112, 9649-9651 9649 Table 1. UV Spectra of Cyclohexadienyl Cation... more Page 1. J. Am. Chem. SOC. 1990, 112, 9649-9651 9649 Table 1. UV Spectra of Cyclohexadienyl Cations cation solvent h(max) el, MI, cm-l X,(max) t2, MI, cm-I OD(Xl)/OD(A2) MESHt HFlP 355 H F/ BF3' 355 1 1 000 HCI/AIC13 ...

ChemInform, 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The Journal of Physical Chemistry, 1993

... Correlation of Reactivity of Alkenes with the 3,4-DimethyleneN(pToluenesulioayl)pyrrole Birad... more ... Correlation of Reactivity of Alkenes with the 3,4-DimethyleneN(pToluenesulioayl)pyrrole Biradial 2f against Their Reactivity with Biradicals 2a and 2b and against Their Mels-Alder Reactivity with Cyclopentadiene The rate constants for quenching the absorption of biradical 2f by ...