Scientific ID number
text
article
2019
per
Journal of New Approaches in Iranian Scientific Laboratories
University of Maragheh
۲۵۸۸-۶۴۰۱
3
v.
2
no.
2019
https://jonaisl.maragheh.ac.ir/article_110307_04908e85ad97276193be68b1b88fc480.pdf
The vital role of blanks in sample preparations
narjes
Behzadimoghadam
. مدیر بازرگانی، آزمایشگاه بسپار پایش پارس، مشهد،
author
javad
feizi
عضو هیئت علمی و رئیس آزمایشگاه مرکزی موسسه پژوهشی علوم و صنایع غذایی
author
پریسا
سراوانی
دانشجوی دکتری شیمی تجزیه. دانشگاه مازندران. بابلسر، ایران
author
text
article
2019
per
The fundamental limitation to accuracy in chemical analysis is systematic error. Systematic error arises whenever the actual nature of the measurement process differs from that assumed. For a measurement to be both accurate and precise the measured value must be corrected for all sources of systematic error or bias and the true value must lie within the stated uncertainty with some stated level of confidence. Accurate chemical determinations require accurate knowledge of the chemical blanks and chemical yields at each stage of the separation process. They are also often included in each analytical run during routine use of the measurement procedure. If the blank correction is not exact, a bias may be introduced in the final value. So the analytical blank may be considered the “Achilles Heel” in chemical analysis. Frequently, precise and otherwise accurate methods produce highly biased results from a lack of knowledge of, or improper consideration of, the chemical blank. For many types of measurements, it is frequently necessary or highly desirable to isolate the element of interest in essentially pure form from the matrix in which it is found. This procedure typically involves decomposition of a sample with mineral acids and isolation of one or more elements by several solvent extraction or ion exchange steps. The aim of this paper is to describe the different kinds of blanks which may be used during method validation and to provide guidance for situations where it may be difficult to obtain a suitable blank matrix.
Journal of New Approaches in Iranian Scientific Laboratories
University of Maragheh
۲۵۸۸-۶۴۰۱
3
v.
2
no.
2019
5
10
https://jonaisl.maragheh.ac.ir/article_101775_631b12be509d2b03b10beda7aad0390c.pdf
Experimental investigation of carbon nanotube length distribution by utilization of scanning electron microscope
غلامرضا
کیانی
عضو هیات علمی-نانوفناوری-نانو الکترونیک- دانشکده مهندسی برق و کامپیوتر دانشگاه تبریز
author
ایوب
کریم زادقویدل
عضو هیات علمی - گروه علوم مهندسی- دانشکده فنی و حرفه ای تبریز- دانشگاه فنی و حرفه ای
author
text
article
2019
per
Due to the special properties, carbon nanotubes(CNT) are attended by many researchers and their applications have been commercialized in many tasks. The high length to diameter ratio called aspect ratio is one of the main difference between CNTs and other nano-particles. Thermal properties of nanofluid and mechanical and electrical properties of polymer based contain CNTs are directly dependent on their length. The current methods for dispersing and separating of nano-particles agglomerations by exerting the damage on the CNTs structure change significantly their length distribution. So, the length distribution after CNTs dispersing and separating have a superior importance. The aim of this paper is the presentation of quick and confident method to prepare the sample and measurement technique for extracting CNTs length distribution by considering economical conditions and time saving. To reach this goal, CNTs were dispersed in chloroform by ultrasonic probe and their length distribution were analyzed by three methods of dynamic light scattered (DLS) atomic force (AFM) and electron scanning microscope(SEM). To prepare the required samples to analyze, the technique was offered named hot bed to prevent re-congesting of CNTs. It was cleared at the end of investigations that CNTs length distribution measurement by using SEM with picture analyzer software like ImageJ is an appropriate method according to this research purpose.
Journal of New Approaches in Iranian Scientific Laboratories
University of Maragheh
۲۵۸۸-۶۴۰۱
3
v.
2
no.
2019
11
14
https://jonaisl.maragheh.ac.ir/article_102489_d8dd47660d02717c9f6357bfc28b6b4f.pdf