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1

Detection system for a miniature MEMS X-ray source

Urbański Paweł, Grzebyk Tomasz

Opto-Electronics Review

|

2023

|

Vol. 31, No. 4

art. no. e147038

EN

The article presents the results of experiments on a detection system used for detecting signals from a miniature, low-energy micro-electro-mechanical system (MEMS) X-ray source. The authors propose to use a detection based on luminescence phenomena occurring in luminophore and scintillators to record the visual signal on a CMOS/CCD detector. The main part of the article is a review of various materials of scintillators and luminophores which would be adequate to convert low-energy X-ray radiation (E < 25 keV - it is a range not typical for conventional X-ray systems) to visible light. Measurements obtained for different energies, exposure times, and different targets have been presented and analysed.

2

Analyzing the identification mechanism of graphite and clay minerale in coal and gangue using X-rays

Yin Jianqiang, Zhu Hongzheng, Zhu Jinbo, Zeng Qiuyu, Li Liansheng, Yang Chenguang

Physicochemical Problems of Mineral Processing

|

2022

|

Vol. 58, iss. 1

24--36

EN

Three types of chelating depressants were studied for chalcopyrite/pyrite separation, including S-S, S-O, and O-O types, via density functional theory calculations and microflotation. The calculation results indicate that the depressant’s chelating atoms have large coefficient and great activity according to the molecular frontier orbital (HOMO and LUMO) and the orbital coefficients. For S-S type of depressant, S atom in both keto or enol forms won’t affect their HOMO and LUMO patterns and the orbital contributions. For S-O type, the presence of N atom in the ring structure of a molecular will increase the reactivity of O-Cu while weak S-Cu. For O-O type, the electron supply capacity of benzene ring is higher than strain chain, and atom N in strain chain increased their electron supply capacity. The microflotation results basically confirmed the prediction based on the calculation. The simulation results demonstrate that the interaction of a depressant with metals and minerals are affected obviously by the spatial structure and electronic structure of an atom in its molecular.

3

History of radiotherapy in Poland. A brief outline of the problem

Gryglewski Richard W.

Bio-Algorithms and Med-Systems

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2021

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Vol. 17, no. 4

227--233

EN

Objectives: The aim of this paper is to give brief outline on the history of radiotherapy in Poland from its beginnings until first decades of the second half of 20th century. Methods: The study is based on comparative and reconstructive analyses of literature, papers and communications dealing with the history of radiotherapy in Poland. Results: The history of radiotherapy in Poland can be perceived as a gradual process of shaping research centres and practical (clinical) application of radiotherapeutics. The Radium Institute in Warsaw, as well as radiotherapy centers in Poznań and Kraków gained key importance in the period up to the outbreak of World War II. After the end of the war, Gliwice became another important place for the history of the radiotherapy and oncology in Poland. Conclusions: Radiotherapy was early recognized by Polish physicians as promising in clinical treatment. It should be a subject of further studies, especially when formative period, thus before First World War, is analysed.

4

Economical evaluation of radiation processing with high-intensity X-rays

Zimek Zbigniew

Nukleonika

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2020

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Vol. 65, No. 3

167--172

EN

X-rays application for radiation processing was introduced to the industrial practice, and in some circumstances is found to be more economically competitive, and offer more flexibility than gamma sources. Recent progress in high-power accelerators development gives opportunity to construct and apply reliable high-power electron beam to X-rays converters for the industrial application. The efficiency of the conversion process depends mainly on electron energy and atomic number of the target material, as it was determined in theoretical predictions and confirmed experimentally. However, the lower price of low-energy direct accelerators and their higher electrical efficiency may also have certain influence on process economy. There are number of auxiliary parameters that can effectively change the economical results of the process. The most important ones are as follows: average beam power level, spare part cost, and optimal shape of electron beam and electron beam utilization efficiency. All these parameters and related expenses may affect the unit cost of radiation facility operation and have a significant influence on X-ray process economy. The optimization of X-rays converter construction is also important, but it does not depend on the type of accelerator. The article discusses the economy of radiation processing with high-intensity of X-rays stream emitted by conversion of electron beams accelerated in direct accelerator (electron energy 2.5 MeV) and resonant accelerators (electron energy 5 MeV and 7.5 MeV). The evaluation and comparison of the costs of alternative technical solutions were included to estimate the unit cost of X-rays facility operation for average beam power 100 kW.

5

Uniqueness Results for Grey Scale Digital Images

Brunetti Sara, Dulio Paolo, Peri Carla

Fundamenta Informaticae

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2020

|

Vol. 172, nr 2

221--238

EN

We address the problem of reconstructing digital images with finitely many grey levels from the knowledge of their X-rays in a given finite set of lattice directions. The main result of the paper provides sets of 2p (p ≥ 3) lattice directions which uniquely determine images with p grey levels, contained in a finite lattice grid. This extends previous uniqueness results for binary images.

6

Synthesis and optical properties of CdSe/CdS core/shell nanocrystals

Gadalla A., Abd El-Sadek M. S., Hamood R.

Materials Science Poland

|

2019

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Vol. 37, No. 2

149--157

EN

This paper attempts to describe an effective method for producing a composite of quantum dots consisting of CdSe (core) with CdS (shell). This nanoparticles composite was synthesized from modified organometallic precursors. The sizes of the nanoparticles were estimated from X-ray diffraction data using Debye-Scherer formula and compared with high resolution electron microscopy (HRTEM) and optical spectra. The shape of CdSe/CdS NPs is nearly spherical and revels that the CdS shell with the thickness ~0.6 nm almost fully covers the CdSe core (higher contrast). Using UV-Vis spectroscopy, a systematic red shift in the absorption and emission spectra was observed after the deposition of CdS which confirms the shell growth over the CdSe core. In the CdSe/CdS core/shell structure, the holes are confined to the core, while the electrons are delocalized as a result of similar electron affinities of the core and the shell. The increased time of synthesis resulted in shell thickness increase. The observed properties of prepared CdSe/CdS QDs demonstrate the capability of the nanocomposite for using in the optoelectronics and photonics devices.

7

Próby rekonstrukcji obrazu fotograficznego na podłożach papierowych. Cz. 3.

Kozielec T.

Przegląd Papierniczy

|

2017

|

R. 73, nr 5

349--356

PL

W artykule zaprezentowano wyniki badań nad rekonstrukcją obrazu fotograficznego z użyciem technik: obrazowania wielospektralnego, neutronowego (radiografia neutronowa) oraz obrazowania z wykorzystaniem technik opartych na użyciu promieniowania rentgenowskiego (MA-XRF, RTG). Zastosowano również techniki oparte na użyciu skaningowego mikroskopu elektronowego SEM/BSE i SEM/EDX. Określono, że najbardziej przydatną techniką do rekonstrukcji spłowiałego obrazu fotograficznego jest obrazowanie wielospektralne (widmo niebieskie i początek widma zielonego). Wszystkie pozostałe techniki nie powodują uczytelnienia się srebrowego obrazu fotograficznego. Zwrócono jednak uwagę na ich przydatność do innych rodzajów badań zabytkowych fotografii. Niniejsza część artykułu jest ostatnią – zamyka poruszoną problematykę badawczą, na której skupił się autor, z drugiej jednak strony ma ona za zadanie otworzenie drogi do dalszych poszukiwań.

EN

In this article the results of photographic image reconstruction investigation are discussed. The following techniques were used in this investigation: multispectral imaging, neutron imaging (neutron radiography) and X radiation techniques (MA-XRF, RTG). The techniques using scanning electron microscopy SEM/BSE and SEM/EDX were also applied. It was found that the most suitable method of faded image reconstruction was multispectral imaging. Other mentioned techniques did not cause the improvement of photographic image readibility. However, they are very useful in other kinds of historic photographs investigation. It is the last part of the article summing up the issues of author’s interest. On the other hand the goal of this part was to open the way for further research.

8

Źródła światła piątej generacji

Romaniuk R. S.

Elektronika : konstrukcje, technologie, zastosowania

|

2016

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Vol. 57, nr 4

42--50

PL

Źródła światła koherentnego są jednym z podstawowych narzędzi badawczych w biologii, technice i innych dziedzinach. Synchrotronowe źródło światła składa się z kilku podstawowych części: źródła energii którym jest akcelerator wiązki elektronowej, konwertera wiązka elektronowa – wiązka fotonowa którym jest undulator, oraz fotonowych linii użytkowych. Każda z tych części osobno jest skomplikowanym urządzeniem podlegającym obecnie szybkiemu rozwojowi technologicznemu. Przyszłościowe źródła światła piątej generacji bazują na zupełnie nowych rozwiązaniach wszystkich tych części podstawowych, w porównaniu ze źródłami poprzednich generacji. Źródłem energii jest nowej generacji miniaturowy akcelerator laserowo-plazmowy o polu elektrycznym rzędu setek GV/m. Miniaturowy undulator testowany jest w technologii MEMS z nowych materiałów. Klasyczne próżniowe i trudne do sterowania linie eksperymentalne i rozprowadzanie wiązki światła zmieniają swoje znaczenie w przypadku dostępności miniaturowych undulatorów umieszczonych tuż przy lub wewnątrz indywidualnej stacji eksperymentalnej. Po wstępie dotyczącym źródeł światła poprzednich generacji, artykuł pokazuje bieżące kierunki badawcze nad wymienionymi częściami składowymi źródeł światła piątej generacji. W niektórych przypadkach jest to kontynuacja i modernizacja poprzednich technologii, w większości jest to odważna próba zastosowania zupełnie nowych technologii jak akceleracji laserowo-plazmowej.

EN

Coherent light sources are one of the most fundamental research tools in biology, technology and in other areas. Synchrotron light source consists of a few basic parts: energy source – which is an electron beam accelerator, energy converter between electron and photon beams – which is an undulator, and photon user experimental lines. Each of these parts is separately a complex system, which is currently a subject to fast technological development. Future light sources of the fifth generation are based on completely new solutions of these fundamental parts, in comparison with the sources of the previous generations. Energy source is a new generation laser – plasma accelerator with electrical field in the area of multiple GV/m. A miniature undulator is tested in the MEMS technology from new materials. Classical light beam lines, vacuum, and difficult for management and beam distribution, change their meaning in the case of availability of miniature undulators positioned immediately at or even inside the experimental stations. After an introduction concerning the light sources of the previous generations, the article shows current research efforts on the mentioned key components of the fifth generation light sources. In some cases this is a continuation and modernization of the previous technologies, in the majority it is a brave endeavour to apply completely new technologies, like laser – plasma acceleration.

9

Application of Fuzzy Logic Toolbox for Predicting Received Doses of Ionizing Radiation Resulting from Partial Discharges

Nagi Ł, Schneider P.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

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2013

|

z. 69

67--68

EN

The paper presents analysis and processing the recaived data from PD where done in MATLAB. It was noted that with the increase in voltage in damaged isulation where PD occur the radiation dose detected by Geiger-Muller Rentgenoradiometr increases too. In order to confirm the theoretical results we were also performed additional modeling curves and use Fuzzy Logic tools in MATLAB.

10

Osłony elastomerowe redukujące dawki promieniowania X w technikach tomografii komputerowe

Kusiak E., Zaborski M., Staniszewska A., Bem H., Szajerski P., Baryń W.

Polimery

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2013

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T. 58, nr 7-8

519--523

PL

Opracowano bezołowiowe osłony redukujące dawki promieniowania w diagnostyce technikami tomografii komputerowej. Podstawę stanowiła matryca z kauczuku naturalnego napełnionego tlenkami: bizmutu, wolframu lub gadolinu. Ze względu na generowanie przez bizmut wtórnego promieniowania fluorescencyjnego rozszerzono pierwotne składy kompozytów. Stwierdzono, że otrzymane kompozyty kauczuku naturalnego zawierające kombinacje tlenków metali charakteryzowały się dużymi wartościami masowych współczynników pochłaniania, wpływały na redukcję natężenia promieniowania padającego o energii: Eg = 60 keV o ok. 50 % a o energii Eg = 122 keV o ok. 20 %. Jednocześnie prawie wszystkie próbki wulkanizatów wykazywały korzystne właściwości wytrzymałościowe.

EN

We have developed lead-free shields reducing the radiation doses in the diagnostic computed tomography techniques. They are based on natural rubber matrix with oxides of bismuth, tungsten and gadolinium as fillers. Due to the generation of secondary fluorescence radiation by bismuth, the study was extended to other compositions. The obtained natural rubber composites containing the combinations of metal oxides were characterized by high values of the mass absorption coefficient, which effected in the reduction in the intensity of incident radiation with an energy Eg = 60 keV by about 50 % and for Eg = 122 keV by about 20 %. It should be noted that virtually all vulcanizates showed good strength properties.

11

Dose sensitivity enhancement on polymer gel with suspended gold particles

Afonso L. C., Schöfer F., Hoeschen Ch., Caldas L. V. E.

Nukleonika

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2012

|

Vol. 57, No. 4

467-472

EN

The presence of high Z material adjacent to soft tissue, when submitted to irradiation, enhances locally the absorbed dose in these soft tissues. Such an effect occurs due to the outscattering of photoelectrons from the high Z material. Polymer gel (PG) dosimeters were used to investigate this effect. Analytic calculations to estimate the dose enhancement were performed. Samples containing a polymer gel with 0.005 gAu/gPG and a pure polymer gel were irradiated using an X-ray beam produced by 150 kV, filtered with 4 mm Al and 5 mm Cu, which resulted in an approximately 20% greater absorbed dose in the samples with gold in comparison to those with the pure polymer gel. The analytic calculations resulted in a dose enhancement factor of approximately 30% for the gold concentration of 0.005 gAu/gPG.

12

Automatyzacja stanowiska pomiarowego do wzorcowania w polu promieniowania rentgenowskiego

Knyziak A.

Przegląd Elektrotechniczny

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2010

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R. 86, nr 5

30-37

PL

W niniejszej pracy przedstawiam kolejne etapy związane z projektowaniem, wykonaniem i uruchomieniem komputerowego systemu pomiarowego pracującego w Głównym Urzędzie Miar na stanowisku wzorcowym do przekazywania jednostki mocy kermy w powietrzu w polu promieniowania rentgenowskiego.

EN

In this work I present consecutive stages of design, fabrication and starting of the computer measurement system at the Central Office of Measures for dissemination of air kerma rate standard in the field of x – rays.

13

Nowoczesne techniki rentgenowskie w badaniach zabytkowych obiektów. Cz. 1

Rafalska-Łasocha A., Łasocha W.

LAB Laboratoria, Aparatura, Badania

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2008

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R. 13, nr 1

6-8

14

Least squares support vector machine based classification of abnormalities in brain MR images

Selvi S., Selvathi D., Ramkumar R., Selvaraj H.

Systems Science

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2006

|

Vol. 32, no 1

89-103

EN

The manual interpretation of MRI slices based on visual examination by radiologist/physician may lead to missing diagnosis when a large number of MRJs arc analyzed. To avoid the human error, an automated intelligent classification system is proposed. This research paper proposes an intelligent classification technique to the problem of classifying four types of brain abnormalities viz. Metastases, Meningiomas, Gliomas, and Astrocytomas. The abnormalities are classified based on Two/Three/ Four class classification using statistical and texlural features. In this work, classification techniques based on Least Squares Support Vector Machine (LS-SVM) using textural features computed from the MR images of patient are developed. LS-SVM classifier using non-linear radial basis function (RBF) kernels is compared with other techniques such as SVM classifier and K-Ncarest Neighbor (K-NN) classifier. It has been observed that the method proposed using LS-SVM classifier outperforms all the other classifiers tested.

15

Stimulatory effects of single low-level irradiations with X-rays on functions of murine peritoneal macrophages

Cheda A., Wrembel-Wargocka J., Nowosielska E., Janiak M.

Nukleonika

|

2005

|

Vol. 50,suppl.2

13-16

EN

A number of epidemiological and experimental data indicate that exposures to low doses of low-LET ionising radiation may trigger the activity of natural anti-tumour immune mechanisms and inhibit tumour growth. In the present study, we assessed the cytotoxic activity and production of nitric oxide, superoxide anions, and tumour necrosis factor-alfa in peritoneal macrophages collected from BALB/c mice exposed to single whole-body irradiations with 0.1, 0.2, or 1.0 Gy X-rays. The results indicate that all the tested parameters were significantly up-regulated in macrophages obtained from mice exposed to 0.1 or 0.2 Gy X-rays but not in those collected from the sham-irradiated and 1.0 Gy-exposed animals.

16

Low-level exposures to ionising radiation modulate the anti-tumour activity of murine NK cells

Nowosielska E., Wrembel-Wargocka J., Cheda A., Lisiak E., Janiak M.

Nukleonika

|

2005

|

Vol. 50,suppl.2

21-24

EN

Experimental evidence from the recent years indicates that low-level irradiations with X- or gamma rays may inhibit development of both primary and secondary tumours and stimulate the activity of natural anti-tumour immune mechanisms. Natural killer (NK) cells play an important role in anti-tumour defence of the host. In the present investigation cytotoxic activity, production of interferon-ă, and expression of the Fas ligand (FasL) were estimated in the NK splenocytes collected from BALB/c mice whose whole body was pre-exposed to irradiation with 0.1, 0.2, or 1.0 Gy X-rays. The results indicate that cytotoxic activity of the irradiated NK cells was significantly stimulated compared to that of the NK effectors obtained from the sham-exposed mice. This effect was totally abrogated by injection of the anti-asialo GM1 antibody. In addition, compared to the control mice, NK cells obtained from the irradiated animals exhibited reduced surface expression of FasL. Collectively, the obtained results suggest that the inhibitory effect of the low-level irradiations with X-rays on the development of pulmonary tumour nodules may be directly associated with stimulation by such exposures of anti-neoplastic functions mediated by NK cells.

17

Local ion density in tracks of secondary electrons generated in tissue by diagnostic X-rays

Golnik N., Zielczyński M.

Biocybernetics and Biomedical Engineering

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2005

|

Vol. 25, no. 1

65-72

EN

Local ion density in the tracks of secondary electrons generated in tissue by diagnostic X-rays was determined on the basis of measurements of the recombination index of the radiation quality (RIQ), measured for X-rays ranging from 40 kVp to 230 kVp, and for several gamma radiation sources. The values obtained ranged from 1 for a (137)Cs gamma radiation source to 1.3+1.9 for X-rays. The peak value was observed for a (241)Am source and for 100 kVp X-rays. Values of RIQ reflect the effective local ion density of the investigated radiation and correlate with the relative biological effectiveness of the radiation.

18

Ultrafast X-ray introspective imaging of metallic objects using a Plasma Focus

Moreno C. H., Clausse A., Martínez J. F., Llovera R., Tartaglione A.

Nukleonika

|

2001

|

Vol. 46, suppl. 1

33--34

EN

A compact-chamber 4.7 kJ, 30 kV, Plasma Focus operated in deuterium was used as a ultrafast high intensity radiation source for introspective radiographic imaging of metallic objects. The samples to be imaged were located outside the Plasma Focus chamber, about 1 m away from the chamber wall. A high-sensitivity, fast-response commercial radiographic film was used as a X-ray detector. Experimentally obtained images are presented showing a very high penetration power of the X-ray beam, demonstrating that the presented compact-chamber Plasma Focus is suited for introspective visualisation of pieces manufactured on metal.

19

Tomographic system based on Plasma Focus X-rays

Venere M., Moreno C. H., Clausse A., Barbuzza R., Del Fresno M.

Nukleonika

|

2001

|

Vol. 46, suppl. 1

93--94

EN

A system oriented to develop an image processing system, which takes advantage of radiation flashes from a plasma focus, by optimizing the emission-detection-reconstruction procedure, is presented. A computer technique for 3D reconstructions was combined with radiographic images of objects X-rayed with a compact plasma focus. The technique is able to automatically determine the position of the rotation axis, reconstruct the 3D-attenuation map, and display inner cuts. The system was demonstrated in introspective tomographic imaging of a stainless steel BNC elbow.

20

Studies of Plasma-Focus discharges within the PF-360 facility equipped with a planar D2O-ice target

Zebrowski J., Baranowski J., Jakubowski L., Sadowski M.

Nukleonika

|

2001

|

Vol. 46, suppl. 1

65--68

EN

The paper reports on investigations of dense magnetized plasmas produced within a modernized PF-360 facility, which was operated with an additional planar cryogenic target placed in the front of the electrode outlet and covered with D2O-ice layers. The main aim of these studies was to overcome the neutron saturation effect and to increase the maximum neutron yield from PF discharges by using fast deuteron beams. Such beams are usually emitted from a pinch region and can produce fast neutrons from D-D reactions during their interactions with the additional target.