Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Q57" wg kryterium: Temat


Tytuł:
Applications of the Cracow X-Ray Microprobe in Tomography
Autorzy:
Bielecki, J.
Bożek, S.
Lekki, J.
Stachura, Z.
Kwiatek, W.
Tematy:
87.59.-e
87.57.Q-
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/1809463.pdf  Link otwiera się w nowym oknie
Opis:
A nuclear microprobe at the IFJ PAN in Cracow has found numerous applications in different fields of research, mostly in biophysics, medical sciences, geology, and material research. In order to extend the research possibilities, a new X-ray microprobe was constructed. This new microprobe consists of three experimental lines dedicated to: (i) X-ray irradiation of biological specimens, (ii) elemental analysis of samples by micro X-ray fluorescence or total reflection X-ray fluorescence methods and (iii) computer microtomography. In this paper the computer microtomography line was described. The line consists of an open type Hamamatsu L9191 X-ray tube with microfocusing to about 2 μm, a high resolution X-ray sensitive CCD camera, and a precise goniometer composed of six piezoelectric motors. Depending on the required X-ray energy, the Hamamatsu tube is used with Ti, Mo, Ag, or W targets. A small focus size and short focus-to-object distance enable to obtain images of samples with a magnification of more than 1000× and resolution of the order of 2 μm. The computer microtomography measurements are carried out using home developed codes combined with commercial software. Details of the microprobe construction and preliminary results of the computer microtomography experiments are presented.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of External Radiation Dose Changes in Some X-ray Applications
Autorzy:
Coşkun, A.
Mavi, B.
Tematy:
87.57.Q-
87.55.N-
87.53.-j
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/1402421.pdf  Link otwiera się w nowym oknie
Opis:
Ionizing radiation is commonly used in diagnostic and therapeutic applications in medicine. Therefore, both staff and patients are exposed to the biological influence of radiation. Biological effects and damages are proportional to the irradiation.In this study the radiation dose to human in the patient room and the technician room at computed tomography and X-ray units were measured and compared for different situations.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Recovering Images from PET Camera
Autorzy:
Üstündağ, D.
Tematy:
02.30.ZZ
02.50.-R
29.30.KV
87.57.Q-
87.57.U
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/1031634.pdf  Link otwiera się w nowym oknie
Opis:
We study here one of the imaging techniques, used in nuclear medicine, called positron emission tomographic imaging, that provides information about many biological processes that are essential to the functioning of the organ, being visualized. Our emphasis is given to the application of the maximum entropy image reconstruction method called "Cambridge MaxEnt Package" for recovering images of the human brain from data obtained by positron emission tomographic camera.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Changing Face of Economics? Ethical Issues in Contemporary Economic Schools as a Consequence of Changes in the Concept of Human Nature
Autorzy:
Horodecka, Anna
Tematy:
business ethics
heterodox economic schools
economic anthropology
concept of human nature
B25
B50
B52
B54
B59
Q57
Z13
Pokaż więcej
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Powiązania:
https://bibliotekanauki.pl/articles/652854.pdf  Link otwiera się w nowym oknie
Opis:
The last financial crisis combined with some recent social trends (like growing inequality or environmental problems) inspired many contemporary economists to the re-evaluation of actual economic knowledge in the search for solutions to these problems. Modern economic schools (especially heterodox ones) stress the meaning of ethical issues in economics more often. The thesis of the paper is that this revival of the ethical face of present economics depends very strongly on the changing assumptions of human nature within economics and other disciplines which work alongside economics, such as social psychology or business ethics, for instance. In order to prove the thesis, the paper provides an evaluation of current economic schools, especially within the heterodoxy, in search of their ethical aspects, and presents them as a result of the changing assumptions about human beings within those schools. This ethical dimension of human beings manifests itself in different ways, which can be perceived as a result of it being based on different ethical schools and different psychological and philosophical assumptions about human nature. Therefore, the paper also considers the current developments of the view on human beings in contemporary schools of economic ethics.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Terahertz Emission from Narrow Gap Semiconductors Photoexcited by Femtosecond Laser Pulses
Autorzy:
Adomavičius, R.
Urbanowicz, A.
Molis, G.
Krotkus, A.
Tematy:
42.65.Re
07.57.Hm
78.47.+p
72.30.+q
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/2041649.pdf  Link otwiera się w nowym oknie
Opis:
Large increase in the emitted terahertz power was observed for p-InAs samples with the p-doping levels of approximately 10$\text{}^{16}$-10$\text{}^{17}$ cm$\text{}^{-3}$. This increase was explained by a large surface depletion layer and an electric-field-induced optical rectification effect in the layer. Terahertz fields radiated by the samples of all three investigated Cd$\text{}_{x}$Hg$\text{}_{1-x}$Te layers was of the same order of magnitude. No azimuthal angle dependence of the radiated signal was detected, which evidences that linear current surge effect is dominating over nonlinear optical rectification. Azimuthal angle and magnetic fields emission witness that it is caused by linear photo-Dember type processes.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Extension of the p-Spectrum Method to the Higher Frequencies
Autorzy:
Pałka, N.
Tematy:
07.57.Ty
78.20.Ci
78.40.-q
78.47.jg
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/1399394.pdf  Link otwiera się w nowym oknie
Opis:
The p-spectrum method is a time domain spectroscopy-based technique for reflection analysis of materials (including explosives) that takes into account only part of the reflected signal, which is next analyzed via the Fourier transform. The method is limited to the frequencies of about 1.8 THz due to the pulse properties of our time domain spectroscopy setup. In this paper we theoretically prove that application of a shorter pulse can increase this frequency range up to 2.2 THz, that enables analysis of penthrite and octogen, two important explosives.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Transmission Spectra of Materials in the Terahertz Range Measured by a Hot Electron Bolometer-Based System
Autorzy:
Pałka, N.
Walczakowski, M.
Zagrajek, P.
Czerwiński, A.
Sypek, M.
Szustakowski, M.
Tematy:
07.57.Ty
78.20.Ci
78.40.-q
78.47.jg
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/1399395.pdf  Link otwiera się w nowym oknie
Opis:
This paper presents an optical system for transmission spectral measurements in the terahertz range. The source of radiation is a tunable solid-state laser, which generates a narrow-band nanosecond pulses in the range 0.67-2.68 THz and based on optical parametric oscillator phenomenon. The signal is detected with a fast and sensitive hot electron bolometer. Principle of generation and detection of pulses as well as methodology of measuring spectral characteristics are presented. We compared the results obtained with the free-space setup, which is based on the optical parametric oscillator and hot electron bolometer, with a purged time domain spectroscopy system in the range of 0.7-2.2 THz.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Robust Algorithm for Heart Rate (HR) Detection and Heart Rate Variability (HRV) Estimation
Autorzy:
Piotrowski, Z.
Różanowski, K.
Tematy:
87.85.Ng
87.19.Le
84.37.+q
87.57.C-
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/1537546.pdf  Link otwiera się w nowym oknie
Opis:
We present algorithm for Heart Rate detection based on Short-Term Autocorrelation Center Clipping method. This algorithm is dedicated for biological signal detection, electrocardiogram, in noisy environment with lot of artifacts. Using this algorithm is also possible detect the R pointers in the PQRST complex of the ECG signal. In this paper the new implementation of the heart rate variability estimation is also presented. HRV module is based on parametric and non-parametric methods of the power spectral density computation.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hyperspectral Imaging Infrared Sensor Used for Enviromental Monitoring
Autorzy:
Kastek, M.
Piatkowski, T.
Zyczkowski, M.
Chamberland, M.
Lagueux, P.
Farley, V.
Tematy:
07.57.Ty
78.20.Ci
78.40.-q
78.47.jg
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/1399366.pdf  Link otwiera się w nowym oknie
Opis:
This paper presents detection, identification and quantification of gases using an infrared imaging Fourier-transform spectrometer. The company Telops has developed an imaging Fourier-transform spectrometer instrument, Hyper-Cam sensor, which is offered as short or long wave infrared sensor. The principle of operation of the spectrometer and the methodology for gases detection, identification and quantification has been shown in the paper, as well as theoretical evaluation of gases detection possibility. The variation of a signal reaching the imaging Fourier-transform spectrometer caused by the presence of a gas has been calculated and compared with the reference signal obtained without the presence of a gas in the imaging Fourier-transform spectrometer field of view. Some result of the detection of various types of gases has been also included in the paper.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Terahertz Emission from the Surfaces of InAs and Other Narrow-Gap Semiconductors
Autorzy:
Adomavičius, R.
Krotkus, A.
Molis, G.
Urbanowicz, A.
Malevich, V.
Tematy:
42.65.Re
07.57.Hm
78.47.-p
72.30.+q
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/1813200.pdf  Link otwiera się w nowym oknie
Opis:
THz pulses were used to investigate carrier dynamics in narrow-gap semiconductors. The measurement of the optically induced THz pulse absorption transients provided important insights into electron energy relaxation in the conduction band. In the second set of experiments, THz generation from the surfaces of various semiconductors was studied and compared. It was found that the most efficient THz emitters are semiconductors with a narrow band gap, large intervalley separation in the conduction band, and low nonparabolicity of the main valley.
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies