CIPAC Meeting 2027
Xi'An, China
CIPAC Meeting 2027

MT 95 - Determinatiom of iron


Content Handbook L

 

Outline of method

95.1 Total iron

95.1.1 Oxidation of divalent iron

The iron present is reduced to divalent iron with a silver reductor, and divalent iron is titrated with cerium(IV) sulphate using ferroin sulphate as indicator.

95.1.2 Reduction of trivalent iron.

The divalent iron present is oxidized with an excess of potassium permanganate and the solution is boiled to destroy the excess. The solution is then titrated with titanium(III) sulphate using ammonium thiocyanate as indicator.

95.1.3 EDTA

The iron is titrated with EDTA using salicylic acid in acetone as indicator.

95.2 Divalent iron

The divalent iron is titrated with cerium(IV) sulphate solution using ferroin sulphate as indicator.



Scope

95.1 Total iron

95.1.1 Oxidation of divalent iron

The method determines total iron. The silver reductor has been chosen for use because it is less subject to interferences than many other methods and gives accurate results.


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 454)
  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 454)
  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:454
  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:454
  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)