Severity: Warning
Message: fopen(/var/lib/php/sessions/ci_sessionn1sjg7qf1dpoohunalmecp3loiugl0g6): Failed to open stream: No space left on device
Filename: drivers/Session_files_driver.php
Line Number: 177
Backtrace:
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)
Filename: Session/Session.php
Line Number: 137
Backtrace:
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: file_get_contents(https://...@pubfacts.com&api_key=b8daa3ad693db53b1410957c26c9a51b4908&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: 3145
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 575
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 489
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
In the present paper the basic theory that an organic substance can emit fluorescence as it is excited by ultraviolet rays is described and the relationships between the molecular structures of organic substances and fluorescence generation are studied. According to this theory, the molecular structures of a few common carbamate pesticides such as carbaryl, carbofuran and propoxur etc.are analyzed, their fluorescence characteristics are shown, and the mechanism of fluorescence generation of carbamate pesticides is ascertained. It provides a theoretic basis for further detecting carbamate pesticides by means of a fluorescence analytical method. Moreover a steady-state fluorescence spectrograph is applied to conduct fluorescence spectrum experiments with standard carbaryl solution and carbofuran solution. The results indicate that carbamate pesticides may emit fluorescence as excited by UV under the condition of a certain solvent, and that their fluorescence spectra are distinct and have fine resolution and less interference. It is feasible to detect carbamate pesticides by fluorescence spectral analysis.
Download full-text PDF |
Source |
---|
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!