The 19^th issue of the electronic journal of laboratory science of Iran is published this fall and by the laboratory network. This issue is the third one of the fifth year of publication of the journal.

According to the public relations and information center of the Vice-Presidency for science and technology affairs, a report on the meeting of managers of members of the strategic technologies laboratory network, which was held this November hosted by the science and industry university of Iran, is published, along with a list of the top centers according to their performance in 2016. In addition, the list of selected intermediators of the network members and top experts of this field is presented as well.

In the 19^th issue of the journal, the first section of the BS EN 13925-1:2003 standard is defined, which involves the defining of concepts, expressing the primary principles and how the constructive interferences interrupt the dispersed beams. X-ray powder diffraction is a non-destructive testing method to determine a range of chemical and physical properties of materials.

The formation of images in transmitted electron microscopes (TEM) requires the passing of electron from the sample. To this end, the sample thickness must be significantly low. On the other hand, decreasing the thickness of sample for this device is time consuming and needs high accuracy. “Preparation and imaging methods of biological samples using Cryo transmitted electron microscope” is the title of an article published in the fall issue of the journal, which completely describe the process.

In another article published in this issue of the journal with the title of “gas chromatography methods to determine the remains of toxins in food”, application of gas chromatography–mass spectrometry device in quantitative and qualitative identification of the compounds present in foods, especially the remaining toxins, is assessed, and a report on the sample preparation stages and short description of the device is presented.

When we work with various chemical compounds, occurrence of various incidents, such as skin contact, swallowing and smelling, are possible. “What are the safety labels in the lab?” is another article of this issue of the journal on the content of safety labels with various compounds or the same SDS and use of their information and symbols and numbers.

“Scalable resistive microscope and some of its applications” is the fourth article published in the 19^th issue of the specialized journal of laboratory science in Iran.

The specialized journal of laboratory science in Iran is the only specialized journal in the non-medical laboratory area of Iran, which is published on the internet, in the form of PDF and free of charge. This journal is available on the website of the strategic technologies laboratory network with the address of www.labsnet.ir and www.IJLK.ir.