Xi'An, China
CIPAC Meeting 2027
CIPAC Meeting 2027

MT 157 - Water solubility

 

Content Handbook F

 

Outline of method

At the test temperature a saturated aqueous solution of the test substance is prepared, and the mass concentration is determined using a suitable analytical method.

157.2 Column Elution Method (Solubility less than 10-2 g/l)

This method is based on the elution of the test substance with water at constant temperature from a column charged with the substance which is finely distributed on an inert support material. The flow rate of the water should be adjusted so that a saturated solution leaves the column. Saturation is achieved when, in consecutive fractions of the eluate at different flow rates, the mass concentration - determined by a suitable method - is constant. This is shown by a plateau when the concentration is plotted against time or eluted volume.

157.3 Flask Method (Solubility above 10-2 g/l)

The test substance is thoroughly distributed in water at 20°C. In a fraction of the suspension, any suspended particles are separated and the concentration of the test substance in the clear solution is determined, using a suitable analytical procedure. Saturation is attained when no significant difference in concentration is found in consecutive tests, and after doubling the time intervals used for the adjustment of equilibrium.

 

Scope

There is no one method to cover the whole range of solubilities in water. This recommendation therefore includes two methods. The column elution method applies to substances with solubility less than approximately 10-2 g/l. The flask method applies to substances with solubilities higher than approximately 10-2 g/l. Which procedure should be applied can be decided using a simple preliminary test.
Both methods are limited to pure solid or liquid substances, not chemically changed by the influence of water, and are not applicable to volatile substances. As yet there is no general definition whether a substance is volatile or not, regarding the applicability of these methods. It is proposed that chemicals having a vapour pressure of more than 0.1 mbar (10 Pa) at 20°C (293 K) should not be submitted to the column elution method unless one can be certain that no significant loss of test substance will occur during the procedure for loading the support material. When using the flask method for substances having a vapour pressure of more than 100 mbar (104 Pa) at 20°C (293 K), it is advisable that additional experimental conditions be observed.

The test substance should be of known purity (ideally, as pure as possible). The identity of the substance to be tested must remain unchanged during the procedure.


Failed to start the session because headers have already been sent by "D:\www\www83\plugins\system\debug\src\Extension\Debug.php" at line 377. (500 Whoops, looks like something went wrong.)

RuntimeException RuntimeException

HTTP 500 Whoops, looks like something went wrong.

Failed to start the session because headers have already been sent by "D:\www\www83\plugins\system\debug\src\Extension\Debug.php" at line 377.

Exceptions 2

RuntimeException

in D:\www\www83\libraries\vendor\joomla\session\src\Storage\NativeStorage.php (line 453)
  1. if ($this->isActive()) {
  2. throw new \RuntimeException('Failed to start the session: already started by PHP.');
  3. }
  5. if (ini_get('session.use_cookies') && headers_sent($file, $line)) {
  6. throw new \RuntimeException(
  7. sprintf('Failed to start the session because headers have already been sent by "%s" at line %d.', $file, $line)
  8. );
  9. }
  11. if (!session_start()) {
NativeStorage->start() in D:\www\www83\libraries\src\Session\Storage\JoomlaStorage.php (line 313)
  1. $this->setId($session_clean);
  2. $cookie->set($session_name, '', ['expires' => time() - 3600 ]);
  3. }
  4. }
  6. parent::start();
  8. // Try loading data from the session
  9. if (!empty($_SESSION['joomla'])) {
  10. $this->data = unserialize(base64_decode($_SESSION['joomla']));
  11. }
JoomlaStorage->start() in D:\www\www83\libraries\vendor\joomla\session\src\Session.php (line 396)
  1. {
  2. if ($this->isStarted()) {
  3. return;
  4. }
  6. $this->store->start();
  8. $this->setState(SessionState::ACTIVE);
  10. // Initialise the session
  11. $this->setCounter();
Session->start() in D:\www\www83\libraries\vendor\joomla\session\src\Session.php (line 327)
  1. * @since 1.0
  2. */
  3. public function has($name)
  4. {
  5. if (!$this->isActive()) {
  6. $this->start();
  7. }
  9. return $this->store->has($name);
  10. }
Session->has() in D:\www\www83\libraries\src\Session\Session.php (line 194)
  2. $name = $args[2] . '.' . $name;
  3. }
  4. }
  6. if (parent::has($name)) {
  7. // Parent is used because of b/c, can be changed in Joomla 6
  8. return parent::get($name, $default);
  9. }
  11. /*
Session->get() in D:\www\www83\libraries\src\Factory.php (line 372)
  1. __CLASS__
  2. ),
  3. E_USER_DEPRECATED
  4. );
  6. $instance = self::getApplication()->getSession()->get('user');
  8. if (\is_null($id)) {
  9. if (!($instance instanceof User)) {
  10. $instance = User::getInstance();
  11. }
Factory::getUser() in D:\www\www83\libraries\src\Document\Renderer\Html\ModulesRenderer.php (line 46)
  1. {
  2. $renderer = $this->_doc->loadRenderer('module');
  3. $buffer = '';
  5. $app = Factory::getApplication();
  6. $user = Factory::getUser();
  7. $frontediting = ($app->isClient('site') && $app->get('frontediting', 1) && !$user->guest);
  8. $menusEditing = ($app->get('frontediting', 1) == 2) && $user->authorise('core.edit', 'com_menus');
  10. foreach (ModuleHelper::getModules($position) as $mod) {
  11. $moduleHtml = $renderer->render($mod, $params, $content);
ModulesRenderer->render() in D:\www\www83\libraries\src\Document\HtmlDocument.php (line 578)
  2. $cbuffer[$hash] = $tmpdata;
  4. $cache->store($cbuffer, 'cbuffer_' . $type);
  5. } else {
  6. $this->setBuffer($renderer->render($name, $attribs, null), $type, $name, $title);
  7. }
  9. return parent::$_buffer[$type][$name][$title];
  10. }
HtmlDocument->getBuffer() in D:\www\www83\libraries\src\Document\HtmlDocument.php (line 897)
  1. $replace = [];
  2. $with = [];
  4. foreach ($this->_template_tags as $jdoc => $args) {
  5. $replace[] = $jdoc;
  6. $with[] = $this->getBuffer($args['type'], $args['name'], $args['attribs']);
  7. }
  9. return str_replace($replace, $with, $this->_template);
  10. }
  11. }
HtmlDocument->_renderTemplate() in D:\www\www83\libraries\src\Document\HtmlDocument.php (line 650)
  2. if (\array_key_exists('csp_nonce', $params) && $params['csp_nonce'] !== null) {
  3. $this->cspNonce = $params['csp_nonce'];
  4. }
  6. $data = $this->_renderTemplate();
  7. parent::render($caching, $params);
  9. return $data;
  10. }
HtmlDocument->render() in D:\www\www83\libraries\src\Document\ErrorDocument.php (line 139)
  1. $this->debug = $params['debug'] ?? false;
  2. $this->error = $this->_error;
  4. $params['file'] = 'error.php';
  6. return parent::render($cache, $params);
  7. }
  9. /**
  10. * Render the backtrace
  11. *
ErrorDocument->render() in D:\www\www83\libraries\src\Error\Renderer\HtmlRenderer.php (line 70)
  1. ob_end_clean();
  2. }
  4. $this->getDocument()->setTitle(Text::_('Error') . ': ' . $error->getCode());
  6. return $this->getDocument()->render(
  7. false,
  8. [
  9. 'template' => $template->template,
  10. 'directory' => JPATH_THEMES,
  11. 'debug' => JDEBUG,
HtmlRenderer->render() in D:\www\www83\libraries\src\Exception\ExceptionHandler.php (line 142)
  1. 'subject' => $app,
  2. 'document' => $renderer->getDocument(),
  3. ])
  4. );
  6. $data = $renderer->render($error);
  8. // If nothing was rendered, just use the message from the Exception
  9. if (empty($data)) {
  10. $data = $error->getMessage();
  11. }
ExceptionHandler::render() in D:\www\www83\libraries\src\Exception\ExceptionHandler.php (line 76)
  1. * @since 3.10.0
  2. */
  3. public static function handleException(\Throwable $error)
  4. {
  5. static::logException($error);
  6. static::render($error);
  7. }
  9. /**
  10. * Render the error page based on an exception.
  11. *
ExceptionHandler::handleException() in D:\www\www83\libraries\src\Application\CMSApplication.php (line 334)
  1. );
  3. // Trigger the onError event.
  4. $this->dispatchEvent('onError', $event);
  6. ExceptionHandler::handleException($event->getError());
  7. }
  9. // Trigger the onBeforeRespond event.
  10. $this->dispatchEvent(
  11. 'onBeforeRespond',
CMSApplication->execute() in D:\www\www83\index.php (line 35)
  2. // Run the application - All executable code should be triggered through this file
  3. require_once dirname(__FILE__) . '/includes/app.php';
  5. $app = JFactory::getApplication('site');
  6. $app->execute();

RuntimeException

Failed to start the session because headers have already been sent by "D:\www\www83\plugins\system\debug\src\Extension\Debug.php" at line 377.

in D:\www\www83\libraries\vendor\joomla\session\src\Storage\NativeStorage.php (line 453)
  1. if ($this->isActive()) {
  2. throw new \RuntimeException('Failed to start the session: already started by PHP.');
  3. }
  5. if (ini_get('session.use_cookies') && headers_sent($file, $line)) {
  6. throw new \RuntimeException(
  7. sprintf('Failed to start the session because headers have already been sent by "%s" at line %d.', $file, $line)
  8. );
  9. }
  11. if (!session_start()) {
NativeStorage->start() in D:\www\www83\libraries\src\Session\Storage\JoomlaStorage.php (line 313)
  1. $this->setId($session_clean);
  2. $cookie->set($session_name, '', ['expires' => time() - 3600 ]);
  3. }
  4. }
  6. parent::start();
  8. // Try loading data from the session
  9. if (!empty($_SESSION['joomla'])) {
  10. $this->data = unserialize(base64_decode($_SESSION['joomla']));
  11. }
JoomlaStorage->start() in D:\www\www83\libraries\vendor\joomla\session\src\Session.php (line 396)
  1. {
  2. if ($this->isStarted()) {
  3. return;
  4. }
  6. $this->store->start();
  8. $this->setState(SessionState::ACTIVE);
  10. // Initialise the session
  11. $this->setCounter();
Session->start() in D:\www\www83\libraries\vendor\joomla\session\src\Session.php (line 327)
  1. * @since 1.0
  2. */
  3. public function has($name)
  4. {
  5. if (!$this->isActive()) {
  6. $this->start();
  7. }
  9. return $this->store->has($name);
  10. }
Session->has() in D:\www\www83\libraries\src\Session\Session.php (line 194)
  2. $name = $args[2] . '.' . $name;
  3. }
  4. }
  6. if (parent::has($name)) {
  7. // Parent is used because of b/c, can be changed in Joomla 6
  8. return parent::get($name, $default);
  9. }
  11. /*
Session->get() in D:\www\www83\libraries\src\Factory.php (line 372)
  1. __CLASS__
  2. ),
  3. E_USER_DEPRECATED
  4. );
  6. $instance = self::getApplication()->getSession()->get('user');
  8. if (\is_null($id)) {
  9. if (!($instance instanceof User)) {
  10. $instance = User::getInstance();
  11. }
Factory::getUser() in D:\www\www83\libraries\src\Application\SiteApplication.php (line 565)
  1. *
  2. * @since 3.2
  3. */
  4. protected function initialiseApp($options = [])
  5. {
  6. $user = Factory::getUser();
  8. // If the user is a guest we populate it with the guest user group.
  9. if ($user->guest) {
  10. $guestUsergroup = ComponentHelper::getParams('com_users')->get('guest_usergroup', 1);
  11. $user->groups = [$guestUsergroup];
SiteApplication->initialiseApp() in D:\www\www83\libraries\src\Application\SiteApplication.php (line 237)
  1. * @since 3.2
  2. */
  3. protected function doExecute()
  4. {
  5. // Initialise the application
  6. $this->initialiseApp();
  8. // Mark afterInitialise in the profiler.
  9. JDEBUG ? $this->profiler->mark('afterInitialise') : null;
  11. // Route the application
SiteApplication->doExecute() in D:\www\www83\libraries\src\Application\CMSApplication.php (line 304)
  1. $this->sanityCheckSystemVariables();
  2. $this->setupLogging();
  3. $this->createExtensionNamespaceMap();
  5. // Perform application routines.
  6. $this->doExecute();
  8. // If we have an application document object, render it.
  9. if ($this->document instanceof \Joomla\CMS\Document\Document) {
  10. // Render the application output.
  11. $this->render();
CMSApplication->execute() in D:\www\www83\index.php (line 35)
  2. // Run the application - All executable code should be triggered through this file
  3. require_once dirname(__FILE__) . '/includes/app.php';
  5. $app = JFactory::getApplication('site');
  6. $app->execute();

Stack Traces 2

[2/2] RuntimeException 
RuntimeException:
Failed to start the session because headers have already been sent by "D:\www\www83\plugins\system\debug\src\Extension\Debug.php" at line 377.

  at D:\www\www83\libraries\vendor\joomla\session\src\Storage\NativeStorage.php:453
  at Joomla\Session\Storage\NativeStorage->start()
     (D:\www\www83\libraries\src\Session\Storage\JoomlaStorage.php:313)
  at Joomla\CMS\Session\Storage\JoomlaStorage->start()
     (D:\www\www83\libraries\vendor\joomla\session\src\Session.php:396)
  at Joomla\Session\Session->start()
     (D:\www\www83\libraries\vendor\joomla\session\src\Session.php:327)
  at Joomla\Session\Session->has()
     (D:\www\www83\libraries\src\Session\Session.php:194)
  at Joomla\CMS\Session\Session->get()
     (D:\www\www83\libraries\src\Factory.php:372)
  at Joomla\CMS\Factory::getUser()
     (D:\www\www83\libraries\src\Document\Renderer\Html\ModulesRenderer.php:46)
  at Joomla\CMS\Document\Renderer\Html\ModulesRenderer->render()
     (D:\www\www83\libraries\src\Document\HtmlDocument.php:578)
  at Joomla\CMS\Document\HtmlDocument->getBuffer()
     (D:\www\www83\libraries\src\Document\HtmlDocument.php:897)
  at Joomla\CMS\Document\HtmlDocument->_renderTemplate()
     (D:\www\www83\libraries\src\Document\HtmlDocument.php:650)
  at Joomla\CMS\Document\HtmlDocument->render()
     (D:\www\www83\libraries\src\Document\ErrorDocument.php:139)
  at Joomla\CMS\Document\ErrorDocument->render()
     (D:\www\www83\libraries\src\Error\Renderer\HtmlRenderer.php:70)
  at Joomla\CMS\Error\Renderer\HtmlRenderer->render()
     (D:\www\www83\libraries\src\Exception\ExceptionHandler.php:142)
  at Joomla\CMS\Exception\ExceptionHandler::render()
     (D:\www\www83\libraries\src\Exception\ExceptionHandler.php:76)
  at Joomla\CMS\Exception\ExceptionHandler::handleException()
     (D:\www\www83\libraries\src\Application\CMSApplication.php:334)
  at Joomla\CMS\Application\CMSApplication->execute()
     (D:\www\www83\index.php:35)
[1/2] RuntimeException 
RuntimeException:
Failed to start the session because headers have already been sent by "D:\www\www83\plugins\system\debug\src\Extension\Debug.php" at line 377.

  at D:\www\www83\libraries\vendor\joomla\session\src\Storage\NativeStorage.php:453
  at Joomla\Session\Storage\NativeStorage->start()
     (D:\www\www83\libraries\src\Session\Storage\JoomlaStorage.php:313)
  at Joomla\CMS\Session\Storage\JoomlaStorage->start()
     (D:\www\www83\libraries\vendor\joomla\session\src\Session.php:396)
  at Joomla\Session\Session->start()
     (D:\www\www83\libraries\vendor\joomla\session\src\Session.php:327)
  at Joomla\Session\Session->has()
     (D:\www\www83\libraries\src\Session\Session.php:194)
  at Joomla\CMS\Session\Session->get()
     (D:\www\www83\libraries\src\Factory.php:372)
  at Joomla\CMS\Factory::getUser()
     (D:\www\www83\libraries\src\Application\SiteApplication.php:565)
  at Joomla\CMS\Application\SiteApplication->initialiseApp()
     (D:\www\www83\libraries\src\Application\SiteApplication.php:237)
  at Joomla\CMS\Application\SiteApplication->doExecute()
     (D:\www\www83\libraries\src\Application\CMSApplication.php:304)
  at Joomla\CMS\Application\CMSApplication->execute()
     (D:\www\www83\index.php:35)