Severity: Warning
Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 143
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 143
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 209
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3098
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Attempt to read property "Count" on bool
Filename: helpers/my_audit_helper.php
Line Number: 3100
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3100
Function: _error_handler
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
The low-energy, electron-stimulated desorption (ESD) of molecular products from amorphous solid water (ASW) films capped with methanol is investigated versus methanol coverage (0-4x10(15) cm(-2)) at 50 K using 100 eV incident electrons. The major ESD products from a monolayer (ML) of methanol on ASW are quite similar to the ESD products from bulk methanol film: H(2), CH(4), H(2)O, C(2)H(6), CO, CH(2)O, and CH(3)OH. For 40 ML ASW films, the molecular oxygen, hydrogen, and water ESD yields from the ASW are suppressed with increasing methanol coverage, while the CH(3)OH ESD yield increases proportionally to the methanol coverage. The suppression of the water ESD products by methanol is consistent with the nonthermal reactions occurring preferentially at or near the ASW/vacuum interface and not in the interior of the film. The water and molecular hydrogen ESD yields from the water layer decrease exponentially with the methanol cap coverage with 1/e constants of approximately 6 x 10(14) and 1.6 x 10(15) cm(-2), respectively. In contrast, the O(2) ESD from the water layer is very efficiently quenched by small amounts of methanol (1/e approximately 6.5 x 10(13) cm(-2)). The rapid suppression of O(2) production by small amounts of methanol is due to reactions between CH(3)OH and the precursors for the O(2)-mainly OH radicals. A kinetic model for the O(2) ESD, which semiquantitatively accounts for the observations, is presented.
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Source |
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http://dx.doi.org/10.1063/1.3081879 | DOI Listing |
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