فهرست مطالب

دانش آزمایشگاهی ایران - سال هشتم شماره 1 (پیاپی 29، بهار 1399)
  • سال هشتم شماره 1 (پیاپی 29، بهار 1399)
  • تاریخ انتشار: 1399/03/27
  • تعداد عناوین: 6
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  • Maryam Khosravi*, Mina Mohebi Morad, Gholam Reza Dehghani Page 5

    Today, microscopic studies of soft samples, such as polymers and life science, are one of the most important issues for sample preparation. Generally, in the preparation of cross sections of samples, common methods such as microtome, ultra microtome and fracture in liquid nitrogen are used. Often, the cuttings resulting from these methods have unintended defects and artifacts, including knife rejection on the sample, soft sample crushing, inappropriate cutting due to the angle between the blade and sample, the effects of machine shake or Knives, the effects of thermal changes during work, shrinkage on the samples, the composition of the resulting layers and the difficulty of separating them, and in addition, it is very time-consuming. Due to the fact that FIB-SEM technique is used as a very powerful technique for sample preparation, inspection and processing of equipment and machining in various fields, in the preparation of samples The above can easily be replaced by minimizing the unwanted effects of conventional methods. Nowadays, in order to improve the efficiency, it is possible to investigate three-dimensional structures on the micro and nano scale, the possibility of studying on the situ, the possibility of preparing sequential films and the ability to create images and control all the stages of preparation and machining of samples. The FIB-SEM technic is very useful. Therefore, in this paper, some of the applications have been studied in order to become familiar with the function of this technique in the life sciences and polymers.

    Keywords: Scanning electron microscope, Focused Ion Beam, Sample prepration
  • Masoud Kazeraninejad*, Mohammad Noroozi, Minoo Barzkar Page 13

    The paper reviews the past 11 years of literature on the application of diode lasers in atomic absorption spectrometry with graphite furnaces (GF), plasmas and flames as atomizers. Experimental arrangements and techniques for powerful absorption measurements as well as the theoretical background are covered. The analytical possibilities of high-resolution spectroscopy, including Dopplerfree techniques for isotope selective measurements and isotope dilution analysis are discussed and various applications of element-selective detection by diode laser atomic absorption in combination with separation techniques, such as liquid (LC) and gas chromatography (GC), and with laser ablation of solid samples, are presented.

    Keywords: Atomic absorption spectrometry, Diode laser, Doppler-free spectroscopy, Element-selective detector
  • Hadi Esfehani*, Farideh Bataghva Page 19

    The analysis of multivariate data and their calibration is rapidly expanding with the development of multichannel chromatographic instruments. By combining chromatographic techniques with a chemometrics based on high-order calibration methods, some previous analysis problems such as complex pre-processing steps, long elution times, or even worse analysis results can be prevented. This paper examines an overview of second- to third-order data that provide theories and applications along with the processing of relevant data in chromatography.

    Keywords: Chemometrics, Statistical Methods, Chromatography, Multivariate Analysis, Second-order advantages, Trilinear model
  • Farideh Bataghva*, Elham Talaei Page 27

    Inductive coupled plasma atomic emission spectroscopy is one of the best emission analysis methods used in a wide variety of applications. The main purpose of this type of atomic decomposition spectroscopy is to identify the elements and quantify them in different environments in negligible quantities. While many ICP-OES users initially viewed this method without interference (compared to the atomic absorption method), the fact is that this device suffers from interference like other methods, though its actual effects on the results may be different from other methods. By definition, an interference increases or decreases the intensity of the analyte, resulting in an incorrect response being recorded. There are various ways to deal with interference. In the following, the types of interactions existing in this method are discussed and ways to deal with these interactions are discussed.

    Keywords: Induced Coupled Plasma Emission Spectrometry, Spectral Interference, ICP, Interference