Severity: Warning
Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09&a=1): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 197
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 197
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 271
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3165
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 597
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 511
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 317
Function: require_once
98%
921
2 minutes
20
The accurate source tracing of volatile organic compounds (VOCs) in complicated source environments is challenging to perform, as similar pollutants may be emitted from different chemical processes. An emission profile-based source tracing method, based on comparing similarities between source profiles and ambient air profiles, was evaluated, and was found to improve the tracing efficiency. Emission profiles were acquired from a typical chemical industrial park in the Yangtze River Delta, China. A total of 30 process-based emission profiles comprising 107 VOC species were investigated and similarities among them were calculated. This analysis demonstrated that the similarities between emissions from various chemical processes are universal. Source tracing was then conducted for six air pollution episodes, based on the emission profile-based source tracing method combined with wind speed and direction data. The results showed that the proposed approach represents an efficient method for source tracing. This study enriches the database of source profiles for petroleum-related industries. The emission profiles from references and the air pollution episodes augment the emission profile database, especially under abnormal emission conditions. The database will more effectively serve future source-tracing cases, creating a virtuous circle that improves source tracing efficiency.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.scitotenv.2020.144694 | DOI Listing |