Scintillator - Photodiode Linear Arrays for X-Ray Inspection System

1997 ◽  
Vol 487 ◽  
Author(s):  
S. M. Ignatov ◽  
V.N. Potapov ◽  
A. V. Fedin ◽  
V. M. Chirkin ◽  
L. I. Urutskoev ◽  
...  

AbstractThe evaluations of the following performances of detectors for design of the radiographic system were carried out by mathematical simulation method and experimentally: sensitivity to absorbed energy, noise level, form of apparatus function for spatial resolution of detectors array.The results of calculations were used for designing of CdWO4-Si arrays with optimal sizes of scintillator and photodiode for resolution ability. At the given stage the quality of radiation detectors was evaluated by spectroscopic methods. At the bias voltage on photodiode 24 V, the sensitivity of detectors has made up (0,95–1,00) × 10−21 C / eV, noise level - (1,50–1,75) ×10−16 C together with electronic noise. Dynamic range at absorbed energy by separate detector is more than 105, what is sufficient to get required image contrast.

2017 ◽  
pp. 116-128
Author(s):  
I. G. Kamyshanskaya

The purpose: analysis of the use by radiologists techniques of post-processing of digital radiographs and the development of practical recommendations on their application.Materials and methods.The technique of post-processing was taken for analysis: negative/positive; filters/optimization of dynamic range; the intensification of the contours and smoothing; image magnification; level/window width densities, and gamma correction. Compiled questionnaire, which the doctor and the radiologist had to answer the questions of how often he uses a particular technique of digital image processing; which, in some cases, the study of what organs he uses post-processing? In total, we analyzed 18 questionnaires and their own experience in digital x-ray machines since 2003.Results.On the basis of interviews and our own experience, the author recommends that you always use the techniques of post-processing x-ray images, starting with the optimization of the dynamic range / filter, which greatly improves the quality of the picture.Conclusions.1. Doctors radiologists in the majority of cases (83%) use the methods of post-processing to analyse digital radiographs. 2. Additional option of post-processing are used most of the time (90–100%), this level and the window width, the intensification of the contours increase.3. Command path smoothing is applied in 1/3 cases (33%).4. Rarely used to optimize dynamic range and FonEqualize.5. Understanding all of the options post-processing of digital radiographs and their active use in practice of the radiologist, will improve the accuracy of x-ray, to avoid repeated shots, and as a consequence, to reduce the radiation dose of the patient.6. Recommended: start post-processing images with optimal dynamic range/filter; for detail is necessary – to change the level/window width, zoom in, sharpen the contours.


2011 ◽  
Vol 1341 ◽  
Author(s):  
A. Hossain ◽  
A. E. Bolotnikov ◽  
G. S. Camarda ◽  
Y. Cui ◽  
R. Gul ◽  
...  

ABSTRACTThe imperfect quality of CdZnTe (CZT) crystals for radiation detectors seriously diminishes their suitability for different applications. Dislocations and other dislocation-related defects, such as sub-grain boundaries and dislocation fields around Te inclusions, engender significant charge losses and, consequently, cause fluctuations in the detector’s output signals, thereby hindering their spectroscopic responses. In this paper, we discuss our results from characterizing CZT material by using a high-spatial-resolution X-ray response mapping system at BNL’s National Synchrotron Light Source. In this paper, we emphasize the roles of these dislocation-related defects and their contributions in degrading the detector’s performance. Specifically, we compare the effects of the sub-grain- and coherent twin-boundaries on the X-ray response maps.


2011 ◽  
Vol 1341 ◽  
Author(s):  
Vello Valdna ◽  
Maarja Grossberg ◽  
Jaan Hiie ◽  
Urve Kallavus ◽  
Valdek Mikli ◽  
...  

ABSTRACTGroup II-VI narrow band gap compounds CdTe ZnCdTe and CdSeTe are known as the most suitable semiconductor materials for the room temperature gamma- and X-ray radiation detectors. In this work we investigated electronic properties of a quaternary compound ZnCdSeTe. Cl Cu Pr Er and oxygen doped host materials were synthesized from the grinded mixture of 6N purity ZnTe CdTe and CdSe by the help of CdCl2 flux. Precautions were applied to achieve an uniform doping and high quality of the crystal surfaces. Residue phases after the thermal treatments were removed by the help of a vacuum annealing. It was found that Zn increases a substitutional solubility of dopants in ZnCdSeTe and thus promotes optoelectronic properties of the ZnCdSeTe alloy. Cl substitutes Te whereas Cu and rare earth elements substitute Zn in ZnCdSeTe. Fabricated polycrystalline samples showed a high performance from NIR via VIS and UV to X-ray band. High stability good linearity and performance of samples was measured under X-ray excitation of Cu Kα 1.54056 Å at 40 kV.


2014 ◽  
Vol 1 (1) ◽  
pp. 47-56 ◽  
Author(s):  
Jan Basche

While calling for culturally sensitive healthcare services in migrant communities, the international nursing literature on intercultural care predominantly describes nursing staff as lacking cultural competences and immigrant customers as lacking cleverness to navigate the labyrinths of national healthcare systems. Congruences in language, culture and religion in the customer-caregiver relationship can decisively improve the quality of care. However, they do not automatically guarantee smooth working processes in monocultural in-home settings. On the contrary, new problems occur here for Turkish caregivers which are unknown to the legions of native professionals who feel challenged by migrants and which go beyond differences such as age, sex, income or education. While no cultural or religious brokering is necessary between customers and personnel in the given context in Germany, new challenges arise when caregivers are expected to legally broker between customers and insurance companies or doctors. Conflicting expectations of customers and management as well as their own colliding social and professional roles put the caregivers in a quandary and must be competently managed.


2020 ◽  
Vol 86 (10) ◽  
pp. 18-22
Author(s):  
K. N. Vdovin ◽  
K. G. Pivovarova ◽  
N. A. Feoktistov ◽  
T. B. Ponamareva

Zinc sulfate is the main component in the composition of the acidic zinc plating electrolyte. Deviation in the electrolyte composition from the optimum content leads to destabilization of the electrolysis process and deteriorate the quality of the resulting zinc coating. The proper quality of a zinc coating obtained by galvanic deposition can be ensured only with timely monitoring and adjustment of the electrolyte composition. A technique of X-ray fluorescence determination of zinc (in terms of zinc sulfate) in an acidic zinc plating electrolyte is proposed. The study was carried out using an ARL Quant’X energy dispersive spectrometer (Thermo Fisher Scientific, USA) with a semiconductor silicon-lithium detector. The features of the spectrometer design are presented. The optimal parameters of excitation and detection of zinc radiation were specified when the electrolyte sample was diluted 1:1000. The ZnKα1 line was used as an analytical line. The plotted calibration graph is linear, the correlation coefficient being 0.999234. The results of zinc determination according to the developed method were compared with the data of the reference method of complexometric titration to prove the reliability of the procedure. The results are characterized by good convergence and accuracy. The proposed method of X-ray fluorescence zinc determination in a zinc plating electrolyte equals complexometric titration in the limiting capabilities and even exceeds the latter in terms of the simplicity of sample preparation and rapidity. The developed method of X-ray fluorescence determination of zinc is implemented in analysis of the electrolyte used in the continuous galvanizing unit at «METSERVIS LLC».


Author(s):  
Lea Christy Restu Kinasih ◽  
Dewi Fatimah ◽  
Veranica Julianti

The selection and determination of appropriate learning strategies can improve the results to be obtained from the application of classroom learning models. This writing aims to discipline students to develop individual abilities of students to be more active in the learning process and improve the quality of learning. The learning process in Indonesia in general only uses conventional learning models that make students passive and undeveloped. In order for the quality of learning to increase, the Team Assisted Individualization learning model is combined with the task learning and forced strategies. The Team Assisted Individualization cooperative learning model is one of the cooperative learning models that combines learning individually and in groups. Meanwhile, task and forced learning strategies are strategies that focus on giving assignments that require students to complete them on time so that the learning process can run effectively. Students are required to do assignments according to the given deadline. This makes students become familiar with the tasks given by the teacher. Combining or modifying the learning model of the assisted individualization team with forced and forced learning strategies is expected to be able to make students more active, disciplined, independent, creative in learning and responsible for the tasks assigned. Therefore this method of incorporation is very necessary in the learning process and can be applied to improve the quality of learning in schools.


Author(s):  
Katherine V. Whittington

Abstract The electronics supply chain is being increasingly infiltrated by non-authentic, counterfeit electronic parts, whose use poses a great risk to the integrity and quality of critical hardware. There is a wide range of counterfeit parts such as leads and body molds. The failure analyst has many tools that can be used to investigate counterfeit parts. The key is to follow an investigative path that makes sense for each scenario. External visual inspection is called for whenever the source of supply is questionable. Other methods include use of solvents, 3D measurement, X-ray fluorescence, C-mode scanning acoustic microscopy, thermal cycle testing, burn-in technique, and electrical testing. Awareness, vigilance, and effective investigations are the best defense against the threat of counterfeit parts.


2021 ◽  
Author(s):  
Toni Wäfler ◽  
Rahel Gugerli ◽  
Giulio Nisoli

We all aim for safe processes. However, providing safety is a complex endeavour. What is it that makes a process safe? And what is the contribution of humans? It is very common to consider humans a risk factor prone to errors. Therefore, we implement sophisticated safety management systems (SMS) in order to prevent potential "human failure". These SMS provide an impressive increase of safety. In safety science this approach is labelled "Safety-I", and it starts to be questioned because humans do not show failures only. On the contrary, they often actively contribute to safety, sometimes even by deviating from a procedure. This "Safety-II" perspective considers humans to be a "safety factor" as well because of their ability to adjust behaviour to the given situation. However, adaptability requires scope of action and this is where Safety-I and Safety-II contradict each other. While the former restricts freedom of action, the latter requires room for manoeuvring. Thus, the task of integrating the Safety-II perspective into SMS, which are traditionally Safety-I based, is difficult. This challenge was the main objective of our project. We discovered two methods that contribute to the quality of SMS by integrating Safety-II into SMS without jeopardizing the Safety-I approach.


2015 ◽  
pp. 50-58
Author(s):  
Thi Dung Nguyen ◽  
Tam Vo

Background: The patients on hemodialysis have a significantly decreased quality of life. One of many problems which reduce the quality of life and increase the mortality in these patients is osteoporosis and osteoporosis associated fractures. Objectives: To assess the bone density of those on hemodialysis by dual energy X ray absorptiometry and to examine the risk factors of bone density reduction in these patients. Patients and Method: This is a cross-sectional study, including 93 patients on chronic hemodialysis at the department of Hemodialysis at Cho Ray Hospital. Results: Mean bone densities at the region of interest (ROI) neck, trochanter, Ward triangle, intertrochanter and total neck are 0.603 ± 0.105; 0.583 ± 0.121; 0.811 ± 0.166; 0.489 ± 0.146; 0.723 ± 0.138 g/cm2 respectively. The prevalences of osteoporosis at those ROI are 39.8%, 15.1%; 28%; 38.7%; and 26.9% respectively. The prevalences of osteopenia at those ROI are 54.8%; 46.3%; 60.2%; 45.2% and 62.7% respectively. The prevalence of osteopososis in at least one ROI is 52.7% and the prevalence of osteopenia in at least one ROI is 47.3%. There are relations between the bone density at the neck and the gender of the patient and the albuminemia. Bone density at the trochanter is influenced by gender, albuminemia, calcemia and phosphoremia. Bone density at the intertrochanter is affected by the gender. Bone density at the Ward triangle is influenced by age and albuminemia. Total neck bone density is influenced by gender, albuminemia and phosphoremia. Conclusion: Osteoporosis in patients on chronic hemodialysis is an issue that requires our attention. There are many interventionable risk factors of bone density decrease in these patients. Key words: Osteoporosis, DEXA, chronic renal failure, chronic hemodialysis


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