Nanosized graphene sheets enhanced photoelectric behavior of carbon film on p-silicon substrate

International Nuclear Information System (INIS)

Yang, Lei; Hu, Gaijuan; Zhang, Dongqing; Diao, Dongfeng

2016-01-01

We found that nanosized graphene sheets enhanced the photoelectric behavior of graphene sheets embedded carbon (GSEC) film on p-silicon substrate, which was deposited under low energy electron irradiation in electron cyclotron resonance plasma. The GSEC/p-Si photodiode exhibited good photoelectric performance with photoresponsivity of 206 mA/W, rise and fall time of 2.2, and 4.3 μs for near-infrared (850 nm) light. The origin of the strong photoelectric behavior of GSEC film was ascribed to the appearance of graphene nanosheets, which led to higher barrier height and photoexcited electron-collection efficiency. This finding indicates that GSEC film has the potential for photoelectric applications.

Study on photoelectric parameter measurement method of high capacitance solar cell

Science.gov (United States)

Zhang, Junchao; Xiong, Limin; Meng, Haifeng; He, Yingwei; Cai, Chuan; Zhang, Bifeng; Li, Xiaohui; Wang, Changshi

2018-01-01

The high efficiency solar cells usually have high capacitance characteristic, so the measurement of their photoelectric performance usually requires long pulse width and long sweep time. The effects of irradiance non-uniformity, probe shielding and spectral mismatch on the IV curve measurement are analyzed experimentally. A compensation method for irradiance loss caused by probe shielding is proposed, and the accurate measurement of the irradiance intensity in the IV curve measurement process of solar cell is realized. Based on the characteristics that the open circuit voltage of solar cell is sensitive to the junction temperature, an accurate measurement method of the temperature of solar cell under continuous irradiation condition is proposed. Finally, a measurement method with the characteristic of high accuracy and wide application range for high capacitance solar cell is presented.

Photoelectric effect in surface-barrier structures

International Nuclear Information System (INIS)

Kononenko, V.K.; Tupenevich, P.A.

1985-08-01

Deviations from the Fowler law were observed when investigating photoelectric emission in p-type ZnTe surface-barrier structures. The revealed peculiarities of the structure photosensitivity spectrum are explained by the electron transitions involving surface states at the metal-semiconductor interface. (author)

Automatic Photoelectric Telescope Service

International Nuclear Information System (INIS)

Genet, R.M.; Boyd, L.J.; Kissell, K.E.; Crawford, D.L.; Hall, D.S.; BDM Corp., McLean, VA; Kitt Peak National Observatory, Tucson, AZ; Dyer Observatory, Nashville, TN)

1987-01-01

Automatic observatories have the potential of gathering sizable amounts of high-quality astronomical data at low cost. The Automatic Photoelectric Telescope Service (APT Service) has realized this potential and is routinely making photometric observations of a large number of variable stars. However, without observers to provide on-site monitoring, it was necessary to incorporate special quality checks into the operation of the APT Service at its multiple automatic telescope installation on Mount Hopkins. 18 references

A Method for Transferring Photoelectric Photometry Data from Apple II+ to IBM PC

Science.gov (United States)

Powell, Harry D.; Miller, James R.; Stephenson, Kipp

1989-06-01

A method is presented for transferring photoelectric photometry data files from an Apple II computer to an IBM PC computer in a form which is compatible with the AAVSO Photoelectric Photometry data collection process.

A new photoelectric ink based on nanocellulose/CdS quantum dots for screen-printing.

Science.gov (United States)

Tang, Aimin; Liu, Yuan; Wang, Qinwen; Chen, Ruisong; Liu, Wangyu; Fang, Zhiqiang; Wang, Lishi

2016-09-05

CdS quantum dots with excellent photoelectrical properties embedded in nanocellulose could be exploited for use in photoelectrical ink. In this work, nanocellulose/CdS quantum dot composites were fabricated by controlling the carboxylate content of the nanocellulose and the molar ratio of Cd(2+)/-COOH. New photoelectric inks were prepared based on the composites, in which the CdS quantum dots acted as the pigment and the nanocellulose as the binder. The results of the photocurrent of the composites showed that the photocurrent could be tailored by the carboxylate content and the molar ratio of Cd(2+)/-COOH. And the photocurrent could be as high as 2μA. The surface tension of the photoelectric ink was 27.80±0.03mN/m and its viscosity was 30.3mPas. The photoelectric ink was stable with excellent fluidity and rheology, it could therefore be applied to screen-printing and three-dimensional (3D) printing. Copyright © 2016 Elsevier Ltd. All rights reserved.

Photoelectric panel with equatorial mounting of drive

Science.gov (United States)

Kukhta, M. S.; Krauinsh, P. Y.; Krauinsh, D. P.; Sokolov, A. P.; Mainy, S. B.

2018-03-01

The relevance of the work is determined by the need to create effective models for sunny energy. The article considers a photoelectric panel equipped with a system for tracking the sun. Efficiency of the system is provided by equatorial mounting, which compensates for the rotation of the Earth by rotating the sunny panel in the plane of the celestial equator. The specificity of climatic and geographical conditions of Tomsk is estimated. The dynamics of power variations of photoelectric panels with equatorial mounting during seasonal fluctuations in Tomsk is calculated. A mobile photovoltaic panel with equatorial mounting of the drive has been developed. The methods of design strategy for placing photovoltaic panels in the architectural environment of the city are presented. Key words: sunny energy, photovoltaics, equatorial mounting, mechatronic model, wave reducer, electric drive.

Photoelectric Emission Measurements on the Analogs of Individual Cosmic Dust Grains

Science.gov (United States)

Abbas, M. M.; Tankosic, D.; Craven, P. D.; Spann, J. F.; LeClair, A.; West, E. A.; Weingartner, J. C.; Tielens, A. G. G. M.; Nuth, J. a.; Camata, R. P.

2006-01-01

The photoelectric emission process is considered to be the dominant mechanism for charging of cosmic dust grains in many astrophysical environments. The grain charge and equilibrium potentials play an important role in the dynamical and physical processes that include heating of the neutral gas in the interstellar medium, coagulation processes in the dust clouds, and levitation and dynamical processes in the interplanetary medium and planetary surfaces and rings. An accurate evaluation of photoelectric emission processes requires knowledge of the photoelectric yields of individual dust grains of astrophysical composition as opposed to the values obtained from measurements on flat surfaces of bulk materials, as it is generally assumed on theoretical considerations that the yields for the small grains are much different from the bulk values. We present laboratory measurements of the photoelectric yields of individual dust grains of silica, olivine, and graphite of approx. 0.09-5 micrometer radii levitated in an electrodynamic balance and illuminated with ultraviolet radiation at 120-160 nm wavelengths. The measured yields are found to be substantially higher than the bulk values given in the literature and indicate a size dependence with larger particles having order-of-magnitude higher values than for submicron-size grains.

Innovation ability and innovation spirit in photoelectric comprehensive experiment teaching

Science.gov (United States)

Wang, Dexing; Zhang, Yang; Wang, Xiaofeng; Zhang, Xiaojun; Zhang, Tao; Sun, Peng

2017-08-01

The traditional experimental teaching methods have some shortcomings in the training the student innovation ability. In order to improve the student practical ability in the photoelectric technology, in this paper new experimental teaching modes are tried and reformed for cultivating the innovative ability of students in the linear CCD experiment. The photoelectric experiment systems are independently designed and completed by students. Compared with the traditional experimental teaching methods, this new methods have a great role in the development of the ability of creative thinking.

Measurements of Photoelectric Yield and Physical Properties of Individual Lunar Dust Grains

Science.gov (United States)

Abbas, M. M.; Tankosic, D.; Craven, P. D.; Spann, J. F.; LeClair, A.; West, F. A.; Taylor, L.; Hoover, R.

2005-01-01

Micron size dust grains levitated and transported on the lunar surface constitute a major problem for the robotic and human habitat missions for the Moon. It is well known since the Apollo missions that the lunar surface is covered with a thick layer of micron/sub-micron size dust grains. Transient dust clouds over the lunar horizon were observed by experiments during the Apollo 17 mission. Theoretical models suggest that the dust grains on the lunar surface are charged by the solar UV radiation as well as the solar wind. Even without any physical activity, the dust grains are levitated by electrostatic fields and transported away from the surface in the near vacuum environment of the Moon. The current dust charging and the levitation models, however, do not fully explain the observed phenomena. Since the abundance of dust on the Moon's surface with its observed adhesive characteristics is believed to have a severe impact on the human habitat and the lifetime and operations of a variety of equipment, it is necessary to investigate the phenomena and the charging properties of the lunar dust in order to develop appropriate mitigating strategies. We will present results of some recent laboratory experiments on individual micro/sub-micron size dust grains levitated in electrodynamic balance in simulated space environments. The experiments involve photoelectric emission measurements of individual micron size lunar dust grains illuminated with UV radiation in the 120-160 nm wavelength range. The photoelectric yields are required to determine the charging properties of lunar dust illuminated by solar UV radiation. We will present some recent results of laboratory measurement of the photoelectric yields and the physical properties of individual micron size dust grains from the Apollo and Luna-24 sample returns as well as the JSC-1 lunar simulants.

The research on teaching reformation of photoelectric information science and engineering specialty experiments

Science.gov (United States)

Zhu, Zheng; Yang, Fan; Zhang, Yang; Geng, Tao; Li, Yuxiang

2017-08-01

This paper introduced the idea of teaching reformation of photoelectric information science and engineering specialty experiments. The teaching reformation of specialty experiments was analyzed from many aspects, such as construction of specialized laboratory, experimental methods, experiment content, experiment assessing mechanism, and so on. The teaching of specialty experiments was composed of four levels experiments: basic experiments, comprehensive and designing experiments, innovative research experiments and engineering experiments which are aiming at enterprise production. Scientific research achievements and advanced technology on photoelectric technology were brought into the teaching of specialty experiments, which will develop the students' scientific research ability and make them to be the talent suitable for photoelectric industry.

Effect of XCOM photoelectric cross-sections on dosimetric quantities calculated with EGSnrc

International Nuclear Information System (INIS)

Hobeila, F.; Seuntjens, J.P.

2002-01-01

The EGSnrc Monte-Carlo code system incorporates improved low energy photon physics such as atomic relaxations and the implementation of bound Compton cross-sections using the impulse approximation. The total cross-section for photoelectric absorption however, still relies on the data by Storm and Israel (S and I). Yet, low energy applications such as brachytherapy (e.g. 125 I) require up-to-date low-energy photoelectric cross-section data. In this paper, we study the dosimetric effects of a simple implementation of NIST XCOM-based photoelectric cross-sections in EGSnrc. This is done by calculating mass energy-absorption coefficients, absorbed dose from point sources, kilovoltage x-ray beams and ion chamber response. In the EGS code system, the PEGS4 routine reads the photoelectric and pair cross-sections for elements from a file (pgspepr.dat) and provides numerical fits for compounds which will be used by EGSnrc. We updated the photoelectric cross-sections of the pgspepr.dat file with the XCOM total photoelectric absorption cross-sections from NIST. After validation of this new implementation, we studied its effects on a number of dosimetrically relevant quantities. Firstly, we calculated mass energy-absorption coefficients by scoring energy transferred in a thin slab of water and air using the DOSRZnrc user code. Secondly, we calculated inverse-square corrected absorbed dose distributions from point sources in water by using an internally developed user code, KERNELph. Thirdly, we studied the differences in free-air ion chamber response calculations. Ion chamber response is defined as the dose to the cavity of an ionization chamber, D gas , positioned with its effective point of measurement at a reference point divided by air-kerma measured free-in-air at the same point. The ion chamber response was calculated using monoenergetic photon beams of energy 10 keV to 200 keV. The comparison of the Storm and Israel photoelectric cross-sections with the XCOM cross

Photoelectric absorption cross sections with variable abundances

Science.gov (United States)

Balucinska-Church, Monika; Mccammon, Dan

1992-01-01

Polynomial fit coefficients have been obtained for the energy dependences of the photoelectric absorption cross sections of 17 astrophysically important elements. These results allow the calculation of X-ray absorption in the energy range 0.03-10 keV in material with noncosmic abundances.

Reform and practice for photoelectric specialty experimental teaching based on virtual simulation experiment platform

Science.gov (United States)

Ye, Yan; Lv, Qingsong; Wu, Maocheng; Xu, Yishen; Gu, Jihua

2017-08-01

In view of some problems about the traditional photoelectric specialty experimental teaching process, such as separation of theoretical teaching and practical teaching, immobilization of experimental teaching contents, low quality of experiments and no obvious effect, we explored and practiced a new experimental teaching model of "theoretical teaching, virtual simulation and physical experiment", which combined the characteristics of photoelectric information science and engineering major and the essential requirements of engineering innovation talents cultivation. The virtual simulation experiment platform has many advantages, such as high performance-to-price ratio, easy operation and open experimental process, which makes virtual simulation combine physical experiment, complete each other with virtual for practical. After the users log into the virtual simulation experimental platform, they will first study the contents of the experiment, clarify the purpose and requirements of the experiment, master the method of using the instrument and the relevant notes, and then use the experimental instruments provided by the platform to build the corresponding experimental system. Once the experimenter's optical path is set incorrectly or the instrument parameters are set incorrectly, the error or warning message will be automatically triggered, and the reference information will be given instructing the student to complete the correct experimental operation. The results of our practice in recent years show that the teaching reform of the photoelectric specialty experiments has not only brought great convenience to the experimental teaching management, broadened the students' thinking and vision, enhanced the students' experimental skills and comprehensive qualities, but also made the students participate in the experiment with their enthusiasm. During the construction of experiment programs, the students' engineering practical ability and independent innovation awareness

Photoelectric method for determination of the moment of formation of an anodic spot

International Nuclear Information System (INIS)

Barinov, V.N.; Goncharov, V.K.; Smirnov, A.V.

1986-01-01

In studying the problem of the effect of the amplitude and form of discharge current pulses on the time for transition from a diffuse discharge form to a contracted one and on the value of the threshold current I /SUB As/ for formation of an anodic spot, the authors used a photoelectric method for determination of the moment of appearance of the anodic spot based on determination of the spectral composition of the plasma at different moments of time after the beginning of discharge initiation. The photoelectric method can be used in studying emission processes on a cathode and also in those cases where both electrodes are made of the same material. An example shows synchronous oscillograms of I /SUB p/ (tau) and J /SUB i/ (tau) for copper electrodes. It is evident that during transition of the discharge to a contracted form with an anodic spot there was a sharp increase of the intensity of deexcitation of the ionic copper line. At the moment of extinction of the anodic spot, the amplitude values of J /SUB i/ (tau) corresponded to a level characteristic of the diffuse form of arc burning

Photoelectric work function studies of carbonaceous films containing Ni nanocrystals

International Nuclear Information System (INIS)

Czerwosz, E.; Dluzewski, P.; Kutner, T.; Stacewicz, T.

2003-01-01

In this paper we present the results of photoelectric work function measurements for carbonaceous films containing Ni nanocrystals. The investigated films were obtained by thermal vacuum deposition method. The structure of films was studied by electron diffraction, transmission microscopy and Raman spectroscopy. Film structure depends on Ni contents in the film volume. Work function determined from photoelectric measurements for all investigated films are similar and lie in the range of 2.65-2.93 eV. The decrease of work function value with the cleaning of the film's surface with UV pulsed laser beam was observed

Preparation and photoelectric properties of p-CaFe2O4/n-WO3 composites

International Nuclear Information System (INIS)

Wan, Ruiqin; Jia, Caihong; Zhang, Weifeng

2012-01-01

Highlights: ► Surface photovoltage spectroscopy investigation on p-CaFe 2 O 4 /n-WO 3 composites. ► The photovoltaic response is enhanced in p-CaFe 2 O 4 /n-WO 3 composites. ► The multielectron process and high rate of carrier migration in WO 3 . - Abstract: Composites of p-CaFe 2 O 4 /n-WO 3 are prepared via a sol–gel technique. Their structures and optical properties are characterized with X-ray diffraction, scanning electron microscopy and UV–vis absorption spectroscopy. The photoelectric characteristics are investigated by surface photovoltage spectroscopy combined with electric field induced surface photovoltage spectroscopy. The results indicate that CaFe 2 O 4 can well form a p–n type composite with WO 3 , and the intensity and spectral region of surface photovoltaic response for the composites are strongly dependent on the molar ratio of two components. The enhancement in photoelectric properties and the effective separation of photogenerated carriers could be attributed to the energy level matching between the two components, multielectron process and the high migration rate in WO 3 .

A practice course to cultivate students' comprehensive ability of photoelectricity

Science.gov (United States)

Lv, Yong; Liu, Yang; Niu, Chunhui; Liu, Lishuang

2017-08-01

After the studying of many theoretical courses, it's important and urgent for the students from specialty of optoelectronic information science and engineering to cultivate their comprehensive ability of photoelectricity. We set up a comprehensive practice course named "Integrated Design of Optoelectronic Information System" (IDOIS) for the purpose that students can integrate their knowledge of optics, electronics and computer programming to design, install and debug an optoelectronic system with independent functions. Eight years of practice shows that this practice course can train students' ability of analysis, design/development and debugging of photoelectric system, improve their ability in document retrieval, design proposal and summary report writing, teamwork, innovation consciousness and skill.

ANALYSIS OF SOLAR POWER STATION SCHEMES ON PHOTOELECTRIC MODULES FOR ELECTRIC CARS CHARGING STATIONS

Directory of Open Access Journals (Sweden)

A. Hnatov

2017-12-01

Full Text Available The analysis of existing schemes for building solar power stations on photoelectric modules with the revealing of their operation principles and functionality has been conducted. The specified technical characteristics of each of the analyzed schemes are given. The structural scheme of the solar charging station for electric cars with determining its functional capabilities and operation features is proposed. The practical application of this scheme will help to reduce the dependence on the general electric power supply network and will create conditions for its total rejection.

CdS/TiO{sub 2} nanocomposite film and its enhanced photoelectric responses to dry air and formaldehyde induced by visible light at room temperature

Energy Technology Data Exchange (ETDEWEB)

Zou, Zhijun, E-mail: zjzou@xynu.edu.cn [Key Laboratory of Advanced Micro/Nano Functional Materials, Department of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000 (China); State Key Laboratory of Material Processing and Die & Mould Technology, Nanomaterials and Smart Sensors Research Laboratory, Department of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Qiu, Yang [Key Laboratory of Advanced Micro/Nano Functional Materials, Department of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000 (China); Xie, Changsheng [State Key Laboratory of Material Processing and Die & Mould Technology, Nanomaterials and Smart Sensors Research Laboratory, Department of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Xu, Jingjing; Luo, Yongsong; Wang, Chunlei; Yan, Hailong [Key Laboratory of Advanced Micro/Nano Functional Materials, Department of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000 (China)

2015-10-05

Highlights: • Photoelectric responses of TiO{sub 2} and CdS/TiO{sub 2} to dry air and formaldehyde were tested. • In contrary to TiO{sub 2}, photoelectric response of CdS/TiO{sub 2} obviously increased. • CdS/TiO{sub 2} nanocomposite device exhibits excellent stability to formaldehyde. • CdS/TiO{sub 2} may be a promising material for developing high performance sensor. - Abstract: Photoelectric responses of pure TiO{sub 2} and CdS/TiO{sub 2} nanocomposite devices to dry air and formaldehyde under visible light irradiation at room temperature were investigated in this work. The pure TiO{sub 2} film was firstly prepared by screen printing and CdS/TiO{sub 2} nanocomposite film by the subsequent SILAR process. XRD, FE-SEM, HR-TEM and UV–vis DRS analysis were employed to examine the fundamental characteristics of as-prepared samples. Photoelectric responses of pure TiO{sub 2} device displayed that no obvious photocurrent was observed upon turning the visible light on either in dry air or in formaldehyde. But in contrary to pure TiO{sub 2} device, the photoelectric response of CdS/TiO{sub 2} nanocomposite device has been obviously enhanced. It is the adding of CdS, which works as a sensitizer, that accounts for the enhanced response and makes the CdS/TiO{sub 2} device sensitive to the visible light. Moreover, the CdS/TiO{sub 2} nanocomposite device exhibits excellent stability to formaldehyde. The present work does not only shed light on the photoelectric gas sensing properties of TiO{sub 2} and CdS/TiO{sub 2}, but also suggests that the CdS/TiO{sub 2} nanocomposite may be a promising material for fabricating visible-light-induced photoelectric gas sensors working at room temperature.

Thought waves remotely affect the performance (output voltage) of photoelectric cells

Science.gov (United States)

Cao, Dayong; Cao, Daqing

2012-02-01

In our experiments, thought waves have been shown to be capable of changing (affecting) the output voltage of photovoltaic cells located from as far away as 1-3 meters. There are no wires between brain and photoelectric cell and so it is presumed only the thought waves act on the photoelectric cell. In continual rotations, the experiments tested different solar cells, measuring devices and lamps, and the experiments were done in different labs. The first experiment was conducted on Oct 2002. Tests are ongoing. Conclusions and assumptions include: 1) the slow thought wave has the energy of space-time as defined by C1.00007: The mass, energy, space and time systemic theory- MEST. Every process releases a field effect electrical vibration which be transmitted and focussed in particular paths; 2) the thought wave has the information of the order of tester; 3) the brain (with the physical system of MEST) and consciousness (with the spirit system of the mind, consciousness, emotion and desire-MECD) can produce the information (a part of them as the Genetic code); 4) through some algorithms such as ACO Ant Colony Optimization and EA Evolutionary Algorithm (or genetic algorithm) working in RAM, human can optimize the information. This Optimizational function is the intelligence; 5) In our experiments, not only can thought waves affect the voltage of the output photoelectric signals by its energy, but they can also selectively increase or decrease those photoelectric currents through remote consciousness interface and a conscious-brain information technology.

Study on Photoelectric Properties of Composite Films of Graphene/Ti02 Nanorods

Directory of Open Access Journals (Sweden)

JIN　Guo-li

2017-02-01

Full Text Available TiOZ nanorods have large specific surface area and the ability of directional transmission electron， based on which can reduce recombination probability of light-generated electrons and holes，and improve the photoelectric conversion efficiency of DSSC. As graphene has low resistivity，good stability and excellent transparency，it can be introduced into anode film to improve the electronic transmission. The TiOZ nanorods were prepared by hydrothermal method，mixed with different quality of graphene. Its length range was 200-300 nm，with a diameter of about 20 nm. The porous graphene/TiOZ nanorods composite film were prepared by using electro- hydrodynamic technique(EHDand compositing TiOZ nanorods with different quality of grapheme. The photoelectric conversion efficiency of the DSSC device prepared with the photo-anode film with graphene mass content of 3 % was 4. 23 %，the photoelectric conversion efficiency increased by 36%，relative to that of no graphene doped TiOZ nanorods photo-anode film.

PHOTOELECTRIC OBSERVATIONS OF HD 8358

Directory of Open Access Journals (Sweden)

Woo-Baik Lee

1989-06-01

Full Text Available UBV photoelectric observations of RS CVn type variable star HD 8358 were made using the 61cm reflector at Sobaeksan Astronomical Observatory. The data were obtained on 15 nights from October 1987 to December 1988. Double peaks of maximum light is seen from the light curve and continuous change of phase in notified from the times of maximum lights. The colors of October, 1987 - January, 1988 observations are bluer in ∆(b-u, but redder in ∆(u-b, than those of November -December, 1988 observations.

A low noise photoelectric signal acquisition system applying in nuclear magnetic resonance gyroscope

Science.gov (United States)

Lu, Qilin; Zhang, Xian; Zhao, Xinghua; Yang, Dan; Zhou, Binquan; Hu, Zhaohui

2017-10-01

The nuclear magnetic resonance gyroscope serves as a new generation of strong support for the development of high-tech weapons, it solves the core problem that limits the development of the long-playing seamless navigation and positioning. In the NMR gyroscope, the output signal with atomic precession frequency is detected by the probe light, the final crucial photoelectric signal of the probe light directly decides the quality of the gyro signal. But the output signal has high sensitivity, resolution and measurement accuracy for the photoelectric detection system. In order to detect the measured signal better, this paper proposed a weak photoelectric signal rapid acquisition system, which has high SNR and the frequency of responded signal is up to 100 KHz to let the weak output signal with high frequency of the NMR gyroscope can be detected better.

16 CFR 1211.11 - Requirements for photoelectric sensors.

Science.gov (United States)

2010-01-01

....11 Section 1211.11 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY...) long. The obstruction is to be centered under the door perpendicular to the plane of the door when in... photoelectric sensor's beam from a position 45 degrees from the plane of the door when in the closed position...

The AAVSO Photoelectric Photometry Program in its Scientific and Socio-Historic Context

Science.gov (United States)

Percy, John R.

2011-05-01

Photoelectric photometry began in the 1900s through the work of Guthnick, Stebbins, and others who constructed and used photometers based on the recently-discovered photoelectric effect. The mid 20th century saw a confluence of several areas of amateur interest: astronomy, telescope making, radio and electronics, and general interest in space. This is the time when AAVSO photoelectric photometry (PEP) began, with observers using mostly hand-built photometers on hand-built telescopes. The 1980s brought a revolution: affordable off-the-shelf solid-state photometers, and infrastructure such as the International Amateur-Professional Photoelectric Photometry (IAPPP) conferences, books, and journal. The AAVSO developed a formal PEP program in the early 1980s. Its emphasis was on long-term monitoring of pulsating red giants. It was competing, not always successfully, with programs such as active sun-like binaries (RS CVn stars) which offered "instant gratification" in the form of publicity and quick publications. Nevertheless, the AAVSO PEP program has, through careful organization, motivation, and feedback to observers, produced extensive scientific results. In this presentation, I shall describe, as examples, my own work, its scientific significance, its educational benefit to dozens of my students, and its satisfaction to the observers. To some extent, the AAVSO PEP program has been superceded by its CCD program, but there is still a useful place for ongoing PEP observations of thousands of variable stars. Reference: http://www.aavso.org/sites/default/files/newsletter/PEP/lastpepnl.pdf Acknowledgements: I thank NSERC Canada for research support, my students, and AAVSO staff and observers, especially Howard Landis.

The Booting-Type ADRC of Airborne Photoelectrical Platform

Directory of Open Access Journals (Sweden)

Xiantao Li

2014-01-01

Full Text Available Customary disturbance rejection in the photoelectrical platform is “passive,” which makes it difficult to further improve the isolation degree owning to the strict restriction of mechanical resonance frequency. In this paper, a booting-type ADRC is proposed, whose disturbance estimation process is guided by target value to reduce the overshoot and lag in the estimated value of disturbance. All kinds of disturbance in the system are modeled in a unified way by using the equivalent disturbance voltage to avoid the complex modeling process. Based on the simplified model, extended state observer (ESO is designed to realize a real-time estimation of the disturbance. Then, the disturbance compensation is added to generate the final control value by combining the customary square lead-lag controller. Experiments are implemented to test the proposed control strategy by mounting the photoelectrical platform on a flight simulator and generating a motion perturbation. Compared with the case of only traditional lead-lag controller, the isolation degree of disturbance is enhanced obviously. And the experiments also illustrate strong robustness of ADRC.

L-shell photoelectric cross section measurements

Energy Technology Data Exchange (ETDEWEB)

Arora, S K; Allawadhi, K L; Sood, B S [Punjabi Univ., Patiala (India). Nuclear Science Labs.

1981-05-14

L-shell photoelectric cross sections in Ta, W, Au, Pb, Th and U at 59.5 keV have been determined using three different versions of Sood's method of measuring the absolute yield of fluorescent x-rays when a target is irradiated with a known flux of photons. The results obtained by all the methods agree with one another showing that no hidden systematic errors are involved in the measurements. The present results are found to compare well with the theoretical calculations of Scofield (Lawrence Livermore Laboratory Report No 51326).

Photoelectric radar servo control system based on ARM+FPGA

Science.gov (United States)

Wu, Kaixuan; Zhang, Yue; Li, Yeqiu; Dai, Qin; Yao, Jun

2016-01-01

In order to get smaller, faster, and more responsive requirements of the photoelectric radar servo control system. We propose a set of core ARM + FPGA architecture servo controller. Parallel processing capability of FPGA to be used for the encoder feedback data, PWM carrier modulation, A, B code decoding processing and so on; Utilizing the advantage of imaging design in ARM Embedded systems achieves high-speed implementation of the PID algorithm. After the actual experiment, the closed-loop speed of response of the system cycles up to 2000 times/s, in the case of excellent precision turntable shaft, using a PID algorithm to achieve the servo position control with the accuracy of + -1 encoder input code. Firstly, This article carry on in-depth study of the embedded servo control system hardware to determine the ARM and FPGA chip as the main chip with systems based on a pre-measured target required to achieve performance requirements, this article based on ARM chip used Samsung S3C2440 chip of ARM7 architecture , the FPGA chip is chosen xilinx's XC3S400 . ARM and FPGA communicate by using SPI bus, the advantage of using SPI bus is saving a lot of pins for easy system upgrades required thereafter. The system gets the speed datas through the photoelectric-encoder that transports the datas to the FPGA, Then the system transmits the datas through the FPGA to ARM, transforms speed datas into the corresponding position and velocity data in a timely manner, prepares the corresponding PWM wave to control motor rotation by making comparison between the position data and the velocity data setted in advance . According to the system requirements to draw the schematics of the photoelectric radar servo control system and PCB board to produce specially. Secondly, using PID algorithm to control the servo system, the datas of speed obtained from photoelectric-encoder is calculated position data and speed data via high-speed digital PID algorithm and coordinate models. Finally, a

Tunable photoelectric response in NiO-based heterostructures by various orientations

Science.gov (United States)

Luo, Yidong; Qiao, Lina; Zhang, Qinghua; Xu, Haomin; Shen, Yang; Lin, Yuanhua; Nan, Cewen

2018-02-01

We engineered various orientations of NiO layers for NiO-based heterostructures (NiO/Au/STO) to investigate their effects on the generation of hot electrons and holes. Our calculation and experimental results suggested that bandgap engineering and the orientation of the hole transport layer (NiO) were crucial elements for the optimization of photoelectric responses. The (100)-orientated NiO/Au/STO achieved the highest photo-current density (˜30 μA/cm2) compared with (111) and (110)-orientated NiO films, which was attributed to the (100) films's lowest effective mass of photogenerated holes (˜1.82 m0) and the highest efficiency of separating and transferring electron-holes of the (100)-orientated sample. Our results opened a direction to design a high efficiency photoelectric solar cell.

The photoelectric yield technique for the characterization of the semiconductor heterostructures

International Nuclear Information System (INIS)

Evangelisti, F.; Di Gaspare, L.

1998-01-01

The paper discusses the use of the photoelectric yield spectroscopy for investigating surface defects and interfaces. Few examples are presented that clearly show the usefulness of the techniques. The heterostructures discussed include crystalline/amorphous and crystalline/crystalline systems

X-Ray Spectro-Polarimetry with Photoelectric Polarimeters

Science.gov (United States)

Strohmayer, T. E.

2017-01-01

We derive a generalization of forward fitting for X-ray spectroscopy to include linear polarization of X-ray sources, appropriate for the anticipated next generation of space-based photoelectric polarimeters. We show that the inclusion of polarization sensitivity requires joint fitting to three observed spectra, one for each of the Stokes parameters, I(E), U(E), and Q(E). The equations for StokesI (E) (the total intensity spectrum) are identical to the familiar case with no polarization sensitivity, and for which the model-predicted spectrum is obtained by a convolution of the source spectrum, F (E), with the familiar energy response function,(E) R(E,E), where (E) and R(E,E) are the effective area and energy redistribution matrix, respectively. In addition to the energy spectrum, the two new relations for U(E) and Q(E) include the source polarization fraction and position angle versus energy, a(E), and 0(E), respectively, and the model-predicted spectra for these relations are obtained by a convolution with the modulated energy response function, (E)(E) R(E,E), where(E) is the energy-dependent modulation fraction that quantifies a polarimeters angular response to 100 polarized radiation. We present results of simulations with response parameters appropriate for the proposed PRAXyS Small Explorer observatory to illustrate the procedures and methods, and we discuss some aspects of photoelectric polarimeters with relevance to understanding their calibration and operation.

Size-controllable synthesis of hierarchical copper carbodiimide microcrystals and their pronounced photoelectric response under visible light

Energy Technology Data Exchange (ETDEWEB)

Liu, Qihui [School of Materials Science and Engineering, Shanghai Institute of Technology, Shanghai 201418 (China); Liu, Yufeng, E-mail: yfliu@mail.sitp.ac.cn [School of Materials Science and Engineering, Shanghai Institute of Technology, Shanghai 201418 (China); Dai, Guozhang [Hunan Key Laboratory for Super-microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha, Hunan 410083 (China); Tian, Li [College of Electrical and Information Engineering, Hunan Institute of Engineering, Xiangtan 411101 (China); Xu, Jiayue; Zhao, Guoying; Zhang, Na; Fang, Yongzheng [School of Materials Science and Engineering, Shanghai Institute of Technology, Shanghai 201418 (China)

2015-12-01

Graphical abstract: - Highlights: • A controllably aqueous method was presented to synthesize two types of CuNCN microcrystals (MCs) at room temperature. • The size and nanostructure can be tuned via controlling the ratio of [NH{sub 3}]/[Cu{sup +}]. • Moreover, prounounced photoelectric response of the as-prepared CuNCN was observed for the first time under the irradiation of visible light at room temperature. • The aqueous synthetic route can provide an inspiration to acquire the other metal carbodiimides nano/microcrystals without the aid of reducing agents. - Abstract: Similar to cupric oxides and sulfides, the nitrogen-containing analogue copper carbodiimide (CuNCN) is considered as a potentially promising photoelectric material. However, there is lack of fundamental investigations on controllable synthesis and photoelectric properties of CuNCN nano/microcrystals. Herein, a facile method was developed to synthesize high-quality CuNCN semiconductor microcrystals with different sizes and hierarchical nanostructures at room temperature. This reaction was carried out in aqueous solutions, avoiding the involvement of non-aqueous solutions and high temperature solid phase reaction during the synthesis of CuNCN microcrystals. Photoelectric response of as-prepared CuNCN microcrystals was first observed under the irradiation of visible light at room temperature. The aqueous synthetic route can also provide an inspiration to acquire other metal carbodiimides nano/microcrystals.

Computer Simulation of Angle-measuring System of Photoelectric Theodolite

International Nuclear Information System (INIS)

Zeng, L; Zhao, Z W; Song, S L; Wang, L T

2006-01-01

In this paper, a virtual test platform based on malfunction phenomena is designed, using the methods of computer simulation and numerical mask. It is used in the simulation training of angle-measuring system of photoelectric theodolite. Actual application proves that this platform supplies good condition for technicians making deep simulation training and presents a useful approach for the establishment of other large equipment simulation platforms

[A quick algorithm of dynamic spectrum photoelectric pulse wave detection based on LabVIEW].

Science.gov (United States)

Lin, Ling; Li, Na; Li, Gang

2010-02-01

Dynamic spectrum (DS) detection is attractive among the numerous noninvasive blood component detection methods because of the elimination of the main interference of the individual discrepancy and measure conditions. DS is a kind of spectrum extracted from the photoelectric pulse wave and closely relative to the artery blood. It can be used in a noninvasive blood component concentration examination. The key issues in DS detection are high detection precision and high operation speed. The precision of measure can be advanced by making use of over-sampling and lock-in amplifying on the pick-up of photoelectric pulse wave in DS detection. In the present paper, the theory expression formula of the over-sampling and lock-in amplifying method was deduced firstly. Then in order to overcome the problems of great data and excessive operation brought on by this technology, a quick algorithm based on LabVIEW and a method of using external C code applied in the pick-up of photoelectric pulse wave were presented. Experimental verification was conducted in the environment of LabVIEW. The results show that by the method pres ented, the speed of operation was promoted rapidly and the data memory was reduced largely.

Photoelectric characteristics of metal-Ga{sub 2}O{sub 3}-GaAs structures

Energy Technology Data Exchange (ETDEWEB)

Kalygina, V. M., E-mail: Kalygina@ngs.ru; Vishnikina, V. V.; Petrova, Yu. S.; Prudaev, I. A.; Yaskevich, T. M. [National Research Tomsk State University (Russian Federation)

2015-03-15

We investigate the effect of thermal annealing in argon and of oxygen plasma processing on the photoelectric properties of GaAs-Ga{sub 2}O{sub 3}-Me structures. Gallium-oxide films are fabricated by photostimulated electrochemical oxidation of epitaxial gallium-arsenide layers with n-type conductivity. The as-deposited films were amorphous, but their processing in oxygen plasma led to the nucleation of β-Ga{sub 2}O{sub 3} crystallites. The unannealed films are nontransparent in the visible and ultraviolet (UV) ranges and there is no photocurrent in structures based on them. After annealing at 900°C for 30 min, the gallium-oxide films contain only β-Ga{sub 2}O{sub 3} crystallites and become transparent. Under illumination of the Ga{sub 2}O{sub 3}-GaAs structures with visible light, the photocurrent appears. This effect can be attributed to radiation absorption in GaAs. The photocurrent and its voltage dependence are determined by the time of exposure to the oxygen plasma. In the UV range, the sensitivity of the structures increases with decreasing radiation wavelength, starting at λ ≤ 230 nm. This is due to absorption in the Ga{sub 2}O{sub 3} film. Reduction in the structure sensitivity with an increase in the time of exposure to oxygen plasma can be caused by the incorporation of defects both at the Ga{sub 2}O{sub 3}-GaAs interface and in the Ga{sub 2}O{sub 3} film.

Metal/Semiconductor and Transparent Conductor/Semiconductor Heterojunctions in High Efficient Photoelectric Devices: Progress and Features

Directory of Open Access Journals (Sweden)

M. Melvin David Kumar

2014-01-01

Full Text Available Metal/semiconductor and transparent conductive oxide (TCO/semiconductor heterojunctions have emerged as an effective modality in the fabrication of photoelectric devices. This review is following a recent shift toward the engineering of TCO layers and structured Si substrates, incorporating metal nanoparticles for the development of next-generation photoelectric devices. Beneficial progress which helps to increase the efficiency and reduce the cost, has been sequenced based on efficient technologies involved in making novel substrates, TCO layers, and electrodes. The electrical and optical properties of indium tin oxide (ITO and aluminum doped zinc oxide (AZO thin films can be enhanced by structuring the surface of TCO layers. The TCO layers embedded with Ag nanoparticles are used to enhance the plasmonic light trapping effect in order to increase the energy harvesting nature of photoelectric devices. Si nanopillar structures which are fabricated by photolithography-free technique are used to increase light-active surface region. The importance of the structure and area of front electrodes and the effect of temperature at the junction are the value added discussions in this review.

Photoelectric conversion properties of electrochemically codeposited graphene oxide–ZnO nanocomposite films

Energy Technology Data Exchange (ETDEWEB)

Li, Yiming; Wang, Dian; Li, Wenyou [School of Materials Science and Engineering, Tongji University, Shanghai, 201804 (China); He, Yunqiu, E-mail: heyunqiu@tongji.edu.cn [School of Materials Science and Engineering, Tongji University, Shanghai, 201804 (China); Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, Shanghai, 201804 (China)

2015-11-05

Graphene oxide (GO)–ZnO nanocomposite films were synthesized on Fluorine doped Tin Oxide (FTO) coated glasses by electrochemical codeposition. The films have a laminated architecture with GO and ZnO alternate layers arranged basically parallel to the substrate. The structures of the composites were characterized using XRD, FE-SEM, FT-IR, XPS, Raman, UV–visible, and electrochemical cyclic voltammetry analyses. The results showed that by increasing Zn:C ratio of the suspensions, there is a series of structural evolutions of the composites, and the percentages of the C–O bonds of GO in the composites decreased. The decreased C–O bonds of GO indicate an increase in the reduction degree of GO, with which its energy gap varies from 1.99 eV to 0.89 eV. Moreover, the energy levels of GO and ZnO in the composites were determined. The results of photoelectrochemical measurements of the films indicated the feasibility of using GO in photoelectric conversion as photoabsorbers. A preliminary study on the relationship between the changes in the photocurrent and the structure of the films has provided clues for further studies on improving the photoelectric conversion properties. - Highlights: • Graphene Oxide–ZnO nanocomposite films were obtained by electrochemical codeposition. • The structure of GO varies with the Zn:C ratio of the depositing suspensions. • The feasibility of using GO as photoabsorbers for photoelectric conversion was verified.

Preparation and photoelectric properties of p-CaFe{sub 2}O{sub 4}/n-WO{sub 3} composites

Energy Technology Data Exchange (ETDEWEB)

Wan, Ruiqin; Jia, Caihong [Key Laboratory of Photovoltaic Materials of Henan Province and School of Physics and Electronics, Henan University, Kaifeng 475004 (China); Zhang, Weifeng, E-mail: wfzhang@henu.edu.cn [Key Laboratory of Photovoltaic Materials of Henan Province and School of Physics and Electronics, Henan University, Kaifeng 475004 (China)

2012-12-15

Highlights: Black-Right-Pointing-Pointer Surface photovoltage spectroscopy investigation on p-CaFe{sub 2}O{sub 4}/n-WO{sub 3} composites. Black-Right-Pointing-Pointer The photovoltaic response is enhanced in p-CaFe{sub 2}O{sub 4}/n-WO{sub 3} composites. Black-Right-Pointing-Pointer The multielectron process and high rate of carrier migration in WO{sub 3}. - Abstract: Composites of p-CaFe{sub 2}O{sub 4}/n-WO{sub 3} are prepared via a sol-gel technique. Their structures and optical properties are characterized with X-ray diffraction, scanning electron microscopy and UV-vis absorption spectroscopy. The photoelectric characteristics are investigated by surface photovoltage spectroscopy combined with electric field induced surface photovoltage spectroscopy. The results indicate that CaFe{sub 2}O{sub 4} can well form a p-n type composite with WO{sub 3}, and the intensity and spectral region of surface photovoltaic response for the composites are strongly dependent on the molar ratio of two components. The enhancement in photoelectric properties and the effective separation of photogenerated carriers could be attributed to the energy level matching between the two components, multielectron process and the high migration rate in WO{sub 3}.

Magnetron sputtering fabrication and photoelectric properties of WSe2 film solar cell device

Science.gov (United States)

Mao, Xu; Zou, Jianpeng; Li, Hongchao; Song, Zhengqi; He, Siru

2018-06-01

Tungsten diselenide (WSe2) films with different growing orientations exhibit diverse photoelectric properties. The WSe2 film with C-axis⊥substrate texture has been prepared and applied to thin-film solar cells. W nanofilms with a thickness of 270 nm were deposited onto the Mo bottom electrode and then heat-treated in selenium vapor to synthesize WSe2 films with a thickness of 1 μm. ZnO films were deposited onto WSe2 films to form a P-N junction and ITO films were deposited subsequently as the conductive layer. X-ray diffractometry, scanning electron microscopy and UV-vis-NIR spectro-analysis instrument were employed to analyze the phase composition, optical absorptivity and micromorphology of WSe2 films and the WSe2 solar cell device. WSe2 films exhibit excellent photoelectric performance with an optical absorption coefficient greater than 105 cm-1 across the visible spectrum. The calculated direct and indirect band gap of the WSe2 films is 1.48 eV and 1.25 eV, respectively. With the application of standard glass/Mo/WSe2/ZnO/ITO/Ag device structure, the open-circuit voltage of the battery device is 82 mV. The short-circuit current density is 2.98 mA/cm2 and the filling factor is 0.32. The photoelectric conversion efficiency of the WSe2 film solar cell device is 0.79%.

Functionalization of carbon nanotubes/graphene by polyoxometalates and their enhanced photo-electrical catalysis

International Nuclear Information System (INIS)

Zhang Shuang-Shuang; Liu Rong-Ji; Zhang Guang-Jin; Gu Zhan-Jun

2014-01-01

Carbon nanotubes and graphene are carbon-based materials, which possess not only unique structure but also properties such as high surface area, extraordinary mechanical properties, high electronic conductivity, and chemical stability. Thus, they have been regarded as an important material, especially for exploring a variety of complex catalysts. Considerable efforts have been made to functionalize and fabricate carbon-based composites with metal nanoparticles. In this review, we summarize the recent progress of our research on the decoration of carbon nanotubes/graphene with metal nanoparticles by using polyoxometalates as key agents, and their enhanced photo-electrical catalytic activities in various catalytic reactions. The polyoxometalates play a key role in constructing the nanohybrids and contributing to their photo-electrical catalytic properties. (invited review — international conference on nanoscience and technology, china 2013)

Inventory Control: Construction of a Photoelectric Colorimeter and Application to Students' Experiments.

Science.gov (United States)

Matsuo, Tsutomu; And Others

1989-01-01

Presented is a photoelectric colorimeter which can be assembled by the student. Reports that it can do many of the same analyses as the SPEC 20 but at a greatly reduced cost using older technology. Presents several experiments to use with the colorimeter. (MVL)

Evidence of vectorial photoelectric effect on Copper

International Nuclear Information System (INIS)

Pedersoli, E.; Banfi, F.; Ressel, B.; Pagliara, S.; Giannetti, C.; Galimberti, G.; Lidia, S.; Corlett, J.; Ferrini, G.; Parmigiani, F.

2005-01-01

Quantum efficiency (QE) measurements of single photon photoemission from a Cu(111) single crystal and a Cu polycrystal photocathodes, irradiated by 150 fs-6.28 eV laser pulses, are reported over a broad range of incidence angle, both in s and p polarizations. The maximum QE (≅4x10 -4 ) for polycrystalline Cu is obtained in p polarization at an angle of incidence θ=65 deg. . We observe a QE enhancement in p polarization which cannot be explained in terms of optical absorption, a phenomenon known as vectorial photoelectric effect. Issues concerning surface roughness and symmetry considerations are addressed. An explanation in terms of nonlocal conductivity tensor is proposed

A spatially resolved study of photoelectric heating and [C II] cooling in the LMC Comparison with dust emission as seen by SAGE

NARCIS (Netherlands)

Rubin, D.; Hony, S.; Madden, S. C.; Tielens, A. G. G. M.; Meixner, M.; Indebetouw, R.; Reach, W.; Ginsburg, A.; Kim, S.; Mochizuki, K.; Babler, B.; Block, M.; Bracker, S. B.; Engelbracht, C. W.; For, B. -Q.; Gordon, K.; Hora, J. L.; Leitherer, C.; Meade, M.; Misselt, K.; Sewilo, M.; Vijh, U.; Whitney, B.

Context. Photoelectric heating is a dominant heating mechanism for many phases of the interstellar medium. We study this mechanism throughout the Large Magellanic Cloud (LMC). Aims. We aim to quantify the importance of the [C II] cooling line and the photoelectric heating process of various

Inventory Control: Construction of a Photoelectric Colorimeter and Application to Students' Experiments (Part 2).

Science.gov (United States)

Matsuo, Tsutomu; And Others

1989-01-01

Discussed are the construction and uses of a version of a photoelectric colorimeter by students. Included are materials needed and four experiments which use the equipment. Sample results are shown. (CW)

Titanium dioxide-coated fluorine-doped tin oxide thin films for improving overall photoelectric property

International Nuclear Information System (INIS)

Li, Bao-jia; Huang, Li-jing; Ren, Nai-fei; Zhou, Ming

2014-01-01

Titanium (Ti) layers were deposited by direct current (DC) magnetron sputtering on commercial fluorine-doped tin oxide (FTO) glasses, followed by simultaneous oxidation and annealing treatment in a tubular furnace to prepare titanium dioxide (TiO 2 )/FTO bilayer films. Large and densely arranged grains were observed on all TiO 2 /FTO bilayer films. The presence of TiO 2 tetragonal rutile phase in the TiO 2 /FTO bilayer films was confirmed by X-ray diffraction (XRD) analysis. The results of parameter optimization indicated that the TiO 2 /FTO bilayer film, which was formed by adopting a temperature of 400 °C and an oxygen flow rate of 15 sccm, had the optimal overall photoelectric property with a figure of merit of 2.30 × 10 −2 Ω −1 , higher than 1.78 × 10 −2 Ω −1 for the FTO single-layer film. After coating a 500 nm-thick AZO layer by DC magnetron sputtering on this TiO 2 /FTO bilayer film, the figure of merit of the trilayer film achieved to a higher figure of merit of 3.12 × 10 −2 Ω −1 , indicating further improvement of the overall photoelectric property. This work may provide a scientific basis and reference for improving overall photoelectric property of transparent conducting oxide (TCO) films.

A device for automatic photoelectric control of the analytical gap for emission spectrographs

Science.gov (United States)

Dietrich, John A.; Cooley, Elmo F.; Curry, Kenneth J.

1977-01-01

A photoelectric device has been built that automatically controls the analytical gap between electrodes during excitation period. The control device allows for precise control of the analytical gap during the arcing process of samples, resulting in better precision of analysis.

Photoelectric properties of the metamorphic InAs/InGaAs quantum dot structure at room temperature

Energy Technology Data Exchange (ETDEWEB)

Golovynskyi, S. L., E-mail: golovynskyi@isp.kiev.ua [Institute of Semiconductor Physics, National Academy of Sciences, pr. Nauki 45, 03028 Kyiv (Ukraine); Seravalli, L.; Trevisi, G.; Frigeri, P.; Gombia, E. [Institute of Materials for Electronics and Magnetism, CNR-IMEM, Parco delle Scienze 37a, I-43100 Parma (Italy); Dacenko, O. I.; Kondratenko, S. V. [Department of Physics, Taras Shevchenko National University of Kyiv, 64 Volodymyrska St., 01601 Kyiv (Ukraine)

2015-06-07

We present the study of optical and photoelectric properties of InAs quantum dots (QDs) grown on a metamorphic In{sub 0.15}Ga{sub 0.85}As buffer layer: such nanostructures show efficient light emission in the telecom window at 1.3 μm (0.95 eV) at room temperature. We prepared a sample with vertical geometry of contacts isolated from the GaAs substrate. The structure is found to be photosensitive in the spectral range above 0.9 eV at room temperature, showing distinctive features in the photovoltage and photocurrent spectra attributed to QDs, InAs wetting layer, and In{sub 0.15}Ga{sub 0.85}As metamorphic buffer, while a drop in the photoelectric signal above 1.36 eV is related to the GaAs layer. No effect of defect centers on the photoelectrical properties is found, although they are observed in the absorption spectrum. We conclude that metamorphic QDs have a low amount of interface-related defects close to the optically active region and charge carriers can be effectively collected into InAs QDs.

Photoelectric UBVRI sequences in the Galactic globular clusters NGC 6752 and NGC 6864

International Nuclear Information System (INIS)

Alvarado, F.; Wenderoth, E.; Alcaino, G.; Liller, W.

1990-01-01

UBVRI photoelectric sequences for the Galactic globular clusters NGC 6752 and NGC 6864 are presented. Both of them include fields suitable for CCD exposures. From five UBV sequences in NGC 6572, only five stars are in common with the previous works. 15 refs

Photoelectric elements of the eclipsing binary XY Ceti

International Nuclear Information System (INIS)

Srivastava, R.K.; Padalia, T.D.

1975-01-01

The absolute elements of the system XY Ceti have been obtained on the basis of the spectroscopic elements given by Popper (1971) and the photoelectric elements derived previously. The colours of the components have been obtained. Both components are found to lie fairly on the Main Sequence. The primary component of the system, however, is slightly more evolved as it shows a tendency to drift away from the Main Sequence. The spectral classes now assigned are A5V (primary) and A7V (secondary). The values of Roche constants indicate that the system is a detached one. (Auth.)

Optical and photoelectric properties of nanolamellar structures obtained by thermal annealing of InSe plates in Zn vapours

Energy Technology Data Exchange (ETDEWEB)

Untila, Dumitru; Evtodiev, Igor [Faculty of Physics and Engineering, Moldova State University, Chisinau (Moldova, Republic of); Ghitu Institute of Electronic Engineering and Nanotechnologies, Academy of Sciences of Moldova, Chisinau (Moldova, Republic of); Caraman, Iuliana [Engineering Department ' ' Vasile Alecsandri' ' , University of Bacau (Romania); Spalatu, Nicolae [Department of Materials Science, Tallinn University of Technology (Estonia); Dmitroglo, Liliana; Caraman, Mihail [Faculty of Physics and Engineering, Moldova State University, Chisinau (Moldova, Republic of)

2018-02-15

The structural, optical and photoelectric properties of InSe crystals grown by Bridgman-Stockbarger method and ZnSe/InSe structures obtained on InSe by thermal annealing in Zn vapours are studied in this paper. The study of structural properties confirms that ZnSe compound is formed. The analysis of photoelectric properties reveal that both the ZnSe-InSe composite layer and the composite/InSe heterojunction are photosensitive in the VIS-NIR spectral region. (copyright 2018 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Titanium dioxide-coated fluorine-doped tin oxide thin films for improving overall photoelectric property

Energy Technology Data Exchange (ETDEWEB)

Li, Bao-jia, E-mail: bjia_li@126.com [School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013 (China); Jiangsu Provincial Key Laboratory of Center for Photon Manufacturing Science and Technology, Jiangsu University, Zhenjiang 212013 (China); Huang, Li-jing [School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013 (China); Jiangsu Provincial Key Laboratory of Center for Photon Manufacturing Science and Technology, Jiangsu University, Zhenjiang 212013 (China); Ren, Nai-fei [Jiangsu Provincial Key Laboratory of Center for Photon Manufacturing Science and Technology, Jiangsu University, Zhenjiang 212013 (China); School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013 (China); Zhou, Ming [The State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)

2014-01-30

Titanium (Ti) layers were deposited by direct current (DC) magnetron sputtering on commercial fluorine-doped tin oxide (FTO) glasses, followed by simultaneous oxidation and annealing treatment in a tubular furnace to prepare titanium dioxide (TiO{sub 2})/FTO bilayer films. Large and densely arranged grains were observed on all TiO{sub 2}/FTO bilayer films. The presence of TiO{sub 2} tetragonal rutile phase in the TiO{sub 2}/FTO bilayer films was confirmed by X-ray diffraction (XRD) analysis. The results of parameter optimization indicated that the TiO{sub 2}/FTO bilayer film, which was formed by adopting a temperature of 400 °C and an oxygen flow rate of 15 sccm, had the optimal overall photoelectric property with a figure of merit of 2.30 × 10{sup −2} Ω{sup −1}, higher than 1.78 × 10{sup −2} Ω{sup −1} for the FTO single-layer film. After coating a 500 nm-thick AZO layer by DC magnetron sputtering on this TiO{sub 2}/FTO bilayer film, the figure of merit of the trilayer film achieved to a higher figure of merit of 3.12 × 10{sup −2} Ω{sup −1}, indicating further improvement of the overall photoelectric property. This work may provide a scientific basis and reference for improving overall photoelectric property of transparent conducting oxide (TCO) films.

Photoelectric Properties of Si Doping Superlattice Structure on 6H-SiC(0001).

Science.gov (United States)

Li, Lianbi; Zang, Yuan; Hu, Jichao; Lin, Shenghuang; Chen, Zhiming

2017-05-25

The energy-band structure and visible photoelectric properties of a p/n-Si doping superlattice structure (DSL) on 6H-SiC were simulated by Silvaco-TCAD. The,n the Si-DSL structures with 40 nm-p-Si/50 nm-n-Si multilayers were successfully prepared on 6H-SiC(0001) Si-face by chemical vapor deposition. TEM characterizations of the p/n-Si DSL confirmed the epitaxial growth of the Si films with preferred orientation and the misfit dislocations with a Burgers vector of 1/3 at the p-Si/n-Si interface. The device had an obvious rectifying behavior, and the turn-on voltage was about 1.2 V. Under the visible illumination of 0.6 W/cm², the device demonstrated a significant photoelectric response with a photocurrent density of 2.1 mA/cm². Visible light operation of the Si-DSL/6H-SiC heterostructure was realized for the first time.

Photoelectric Properties of Si Doping Superlattice Structure on 6H-SiC(0001

Directory of Open Access Journals (Sweden)

Lianbi Li

2017-05-01

Full Text Available The energy-band structure and visible photoelectric properties of a p/n-Si doping superlattice structure (DSL on 6H-SiC were simulated by Silvaco-TCAD. The,n the Si-DSL structures with 40 nm-p-Si/50 nm-n-Si multilayers were successfully prepared on 6H-SiC(0001 Si-face by chemical vapor deposition. TEM characterizations of the p/n-Si DSL confirmed the epitaxial growth of the Si films with preferred orientation and the misfit dislocations with a Burgers vector of 1/3 <21-1> at the p-Si/n-Si interface. The device had an obvious rectifying behavior, and the turn-on voltage was about 1.2 V. Under the visible illumination of 0.6 W/cm2, the device demonstrated a significant photoelectric response with a photocurrent density of 2.1 mA/cm2. Visible light operation of the Si-DSL/6H-SiC heterostructure was realized for the first time.

Optical and photoelectrical studies of gold nanoparticle-decorated C{sub 60} films

Energy Technology Data Exchange (ETDEWEB)

Dmitruk, N.L., E-mail: dmitruk@isp.kiev.u [Institute for Physics of Semiconductors, National Academy of Sciences of Ukraine, 45 Nauki Prospect, Kyiv 03028 (Ukraine); Borkovskaya, O.Yu.; Mamykin, S.V.; Naumenko, D.O. [Institute for Physics of Semiconductors, National Academy of Sciences of Ukraine, 45 Nauki Prospect, Kyiv 03028 (Ukraine); Meza-Laguna, V. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico (UNAM), Circuito Exterior, Ciudad Universitaria, A. P. 70-186, C. P. 04510 Mexico D.F. (Mexico); Basiuk Golovataya-Dzhymbeeva, E.V. [Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico (UNAM), Circuito exterior S/N Ciudad Universitaria, A. P. 70-186, C. P. 04510 Mexico D.F. (Mexico); Lee, I. Puente [Facultad de Quimica, UNAM, Circuito de la Investigacion Cientifica, Ciudad Universitaria, 04510 Mexico D.F. (Mexico)

2010-01-01

Optical and photoelectrical studies were performed on octane-1,8-dithiol cross-linked fullerene films, with supported gold nanoparticles (C{sub 60}-DT-Au). According to high-resolution transmission electron microscopy observations, the average size of obtained gold nanoparticles was about 5 nm, and the shape was spherical. The comparative investigation of optical properties of pristine and cross-linked with octane-1,8-dithiol C{sub 60} films, decorated with gold nanoparticles, found the difference in the extinction coefficient spectra, which was observed also in the photocurrent spectra of barrier heterostructure Au/C{sub 60}/Si. The analysis of dark current-voltage characteristics for Au/C{sub 60}/Si heterostructures showed that the model for them includes the barrier at the C{sub 60}/Si interface and internal barriers in the C{sub 60} layer, caused by the trapping centers. The hopping mechanism of the current transport in the C{sub 60} layer was supplemented with the Poole-Frenkel emission process on these centers, with the barrier height greater for the fullerene C{sub 60} film cross-linked with octane-1,8-dithiol.

Singularities of current-voltage characteristics of GaAs films fabricated by pulsed ions ablation

International Nuclear Information System (INIS)

Kabyshev, A.V.; Konusov, F.V.; Lozhnikov, S.N.; Remnev, G.E.; Saltymakov, M.S.

2009-01-01

A singularities and advantages of the optical, photoelectric and electrical properties of GaAs in comparison with other available materials for electronics, for example, silicon allow to manufacture on it base the devices having an advanced characteristics. The GaAs for electronics, obtained from the dense ablation plasma, possess some preferences as compared to material manufactured by traditional methods of vacuum deposition. The electrical characteristics of GaAs produced by chemical deposition were extensively studied. Purpose of this work is investigation the current-voltage characteristics of thin films of GaAs, deposited on polycrystalline corundum (polycor) from plasma forming the power ions bunch and determination of the thermal vacuum annealing effect on photoelectric and electrical properties of films. Peculiarities of optical, photoelectric and current-voltage characteristics of films obtained by ions ablation are determined by deposition conditions and resistance of initial target GaAs. The transitions between the states with low- and high conduction were revealed directly after deposition in films having the optical properties similar to amorphous materials and/or after annealing in films with properties similar to initial target GaAs. Behavior of current-voltage characteristics at vacuum annealing correlates with Schottky barrier height and photosensitivity and is accompanies of the transport mechanism change. The stable properties of films are formed at its dark conduction 10 -10 -10 -8 s and after annealing at T an =600-700 K. (authors)

Recordings of mucociliary activity in vivo: benefit of fast Fourier transformation of the photoelectric signal.

Science.gov (United States)

Lindberg, S; Cervin, A; Runer, T; Thomasson, L

1996-09-01

Investigations of mucociliary activity in vivo are based on photoelectric recordings of light reflections from the mucosa. The alterations in light intensity produced by the beating cilia are picked up by a photodetector and converted to photoelectric signals. The optimal processing of these signals is not known, but in vitro recordings have been reported to benefit from fast Fourier transformation (FFT) of the signal. The aim of the investigation was to study the effect of FFT for frequency analysis of photoelectric signals originating from an artificial light source simulating mucociliary activity or from sinus or nasal mucosa in vivo, as compared to a conventional method of calculating mucociliary wave frequency, in which each peak in the signal is interpreted as a beat (old method). In the experiments with the artificial light source, the FFT system was superior to the conventional method by a factor of 50 in detecting weak signals. By using FFT signal processing, frequency could be correctly calculated in experiments with a compound signal. In experiments in the rabbit maxillary sinus, the spontaneous variations were greater when signals were processed by FFT. The correlation between the two methods was excellent: r = .92. The increase in mucociliary activity in response to the ciliary stimulant methacholine at a dosage of 0.5 microgram/kg was greater measured with the FFT than with the old method (55.3% +/- 8.3% versus 43.0% +/- 8.2%, p detected. In the human nose, recordings from aluminum foil placed on the nasal dorsum and from the nasal septa mucosa displayed some similarities in the lower frequency spectrum (light, the mean frequency in seven healthy volunteers being 7.8 +/- 1.6 Hz for the human nasal mucosa. It is concluded that the FFT system has greater sensitivity in detecting photoelectric signals derived from the mucociliary system, and that it is also a useful tool for analyzing the contributions of artifacts to the signal.

One-step electrochemical synthesis and photoelectric conversion of a ZnO/Se/RGO composite

International Nuclear Information System (INIS)

Wang, Lei; Zhang, Chunyan; Zhang, Shengyi; Niu, Helin; Song, Jiming; Mao, Changjie; Jin, Baokang; Tian, Yupeng

2015-01-01

Using Zn(NO 3 ) 2 , H 2 SeO 3 and graphene oxide as precursors, the zinc oxide/selenium/reduced graphene oxide (ZnO/Se/RGO) composite was facilely electrodeposited on the surface of indium tin oxide glass. The conditions for electrochemical synthesis such as electrodeposition potential and electrolyte composition were studied. The morphology and crystallization of the products as-prepared were characterized using scanning electron microscopy (SEM) and x-ray diffractometry (XRD) respectively. The light absorption and conductivity of the products were studied by UV-visible spectroscopy (UV-vis) and electrochemical impedance spectroscopy (EIS). Based on a series of experimental results, the photoelectrical conversion mechanism and effect factors of the products were explored. By means of synergistic action of n-type ZnO, p-type Se and conductive RGO, the ZnO/Se/RGO composite showed excellent photoelectric conversion under visible light irradiation. (paper)

Influence of semiconductor surface preparation on photoelectric properties of Al-Zn{sub 3}P{sub 2} contacts

Energy Technology Data Exchange (ETDEWEB)

Mirowska, Nella [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland)]. E-mail: nella.mirowska@pwr.wroc.pl; Misiewicz, Jan [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland)

2006-06-15

The Schottky barriers formed by Al on Zn{sub 3}P{sub 2} p-type crystals have been studied. Three types of crystals (monocrystal, large-grain crystal and polycrystal) were used for device fabrication. The samples were separated in two groups according to the type of structure and the methods of surface preparation. The samples from the first group were different in structure (monocrystal, large-grain crystal and polycrystals) but prepared in the same way. Three polycrystals with differently prepared surfaces were collected in the second group. Two samples from this group were also annealed in open air at 523 K for 24 h. Measurements of photovoltaic effect at room temperature were carried out to test the impact of surface preparation on photoelectric properties of Al-Zn{sub 3}P{sub 2} contacts. Substantial differences in shape and intensity of PV signal were observed depending on whether the surface of semiconductor was mechanically polished, chemically etched or/and heat treated. The height of potential barrier, {phi} {sub B}, and optical transitions in semiconductor were determined. The value of {phi} {sub B} changed from 0.747 to 0.767 eV for unheated samples and from 0.724 to 0.755 eV for the heated ones. The quality of semiconductor surface seems to have an essential influence on spectral characteristics of Al-Zn{sub 3}P{sub 2} junctions, especially in the case of polycrystals. It appeared that thorough preliminary mechanical polishing of crystals surface provides quite good photoelectric properties of Al-Zn{sub 3}P{sub 2} junctions.

Electron track reconstruction and improved modulation for photoelectric X-ray polarimetry

Energy Technology Data Exchange (ETDEWEB)

Li, Tenglin [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China); Zeng, Ming, E-mail: zengming@tsinghua.edu.cn [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China); Feng, Hua [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China); Center for Astrophysics, Tsinghua University, Beijing 100084 (China); Cang, Jirong [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China); Li, Hong; Zhang, Heng [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China); Center for Astrophysics, Tsinghua University, Beijing 100084 (China); Zeng, Zhi; Cheng, Jianping; Ma, Hao; Liu, Yinong [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China)

2017-06-21

The key to photoelectric X-ray polarimetry is the determination of the emission direction of photoelectrons. Because of the low mass of an electron, the ionisation trajectory is not straight and the useful information needed for polarimetry is stored mostly in the initial part of the track where less energy is deposited. We present a new algorithm, based on the shortest path problem in graph theory, to reconstruct the 2D electron track from the measured image that is blurred due to transversal diffusion along drift and multiplication in the gas chamber. Compared with previous methods based on moment analysis, this algorithm allows us to identify the photoelectric interaction point more accurately and precisely for complicated tracks resulting from high energy photons or low pressure chambers. This leads to a better position resolution and a higher degree of modulation toward high energy X-rays. The new algorithm is justified using simulations and measurements with the gas pixel detector (GPD), and it should also work for other polarimetric techniques such as a time projection chamber (TPC). As the improvement is restricted in the high energy band, this new algorithm shows limited improvement for the sensitivity of GPD polarimeters, but it may have a larger potential for low-pressure TPC polarimeters.

Favorable ultraviolet photoelectric effects in TbMnO3/Nb-SrTiO3 heterostructures

KAUST Repository

Jin, Kexin; Zhai, Y. X.; Li, Hui; Tian, Y. F.; Luo, B. C.; Wu, Tao

2014-01-01

The rectifying properties and ultraviolet photoelectric effects in TbMnO3/Nb-doped SrTiO3 heterostructures have been investigated. The ideality factors and the diffusion voltages obtained from the current-voltage curves nonlinearly decrease

Synthesis of Water-Soluble Antimony Sulfide Quantum Dots and Their Photoelectric Properties.

Science.gov (United States)

Zhu, Jiang; Yan, Xuelian; Cheng, Jiang

2018-01-15

Antimony sulfide (Sb 2 S 3 ) has been applied in photoelectric devices for a long time. However, there was lack of information about Sb 2 S 3 quantum dots (QDs) because of the synthesis difficulties. To fill this vacancy, water-soluble Sb 2 S 3 QDs were prepared by hot injection using hexadecyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) mixture as anionic-cationic surfactant, alkanol amide (DEA) as stabilizer, and ethylenediaminetetraacetic acid (EDTA) as dispersant. Photoelectric properties including absorbing and emission were characterized by UV-Vis-IR spectrophotometer and photoluminescence (PL) spectroscopic technique. An intensive PL emission at 880 nm was found, indicating Sb 2 S 3 QDs have good prospects in near-infrared LED and near-infrared laser application. Sb 2 S 3 QD thin films were prepared by self-assembly growth and then annealed in argon or selenium vapor. Their band gaps (E g s) were calculated according to transmittance spectra. The E g of Sb 2 S 3 QD thin film has been found to be tunable from 1.82 to 1.09 eV via annealing or selenylation, demonstrating the good prospects in photovoltaic application.

Sound card based digital correlation detection of weak photoelectrical signals

International Nuclear Information System (INIS)

Tang Guanghui; Wang Jiangcheng

2005-01-01

A simple and low-cost digital correlation method is proposed to investigate weak photoelectrical signals, using a high-speed photodiode as detector, which is directly connected to a programmably triggered sound card analogue-to-digital converter and a personal computer. Two testing experiments, autocorrelation detection of weak flickering signals from a computer monitor under background of noisy outdoor stray light and cross-correlation measurement of the surface velocity of a motional tape, are performed, showing that the results are reliable and the method is easy to implement

Photoelectrically automated, bakeable, high-load ultramicrobalance

International Nuclear Information System (INIS)

Czanderna, A.W.; Kollen, W.; Biegen, J.R.; Rodder, J.

1976-01-01

An all quartz pivotal-beam ultramicrobalance has been modified for operation as a null instrument using a dual-path photoelectric detector. The beam and newly designed stainless steel beam support have been adapted to a stainless steel enclosure for studies in uhv. A thin quartz disk, with a 600-A thick Au film for partially blocking the light path, is fused to each end of the beam. An electronic circuit minimizes the signal from the detector when the balance moves from the null by providing a current output to a magnetic compensation coil. The capacity (up to 20 g), the stability of the null reading (over six months), and the unusually high load to precision ratio (1--2x10 8 ) of the balance have been maintained with the modification. Sensibilities of 0.03--0.1 μg with 4--10-g loads have been obtained with the balance, which is now completely adapted for UHV operation

Analysis on detection accuracy of binocular photoelectric instrument optical axis parallelism digital calibration instrument

Science.gov (United States)

Ying, Jia-ju; Yin, Jian-ling; Wu, Dong-sheng; Liu, Jie; Chen, Yu-dan

2017-11-01

Low-light level night vision device and thermal infrared imaging binocular photoelectric instrument are used widely. The maladjustment of binocular instrument ocular axises parallelism will cause the observer the symptom such as dizziness, nausea, when use for a long time. Binocular photoelectric equipment digital calibration instrument is developed for detecting ocular axises parallelism. And the quantitative value of optical axis deviation can be quantitatively measured. As a testing instrument, the precision must be much higher than the standard of test instrument. Analyzes the factors that influence the accuracy of detection. Factors exist in each testing process link which affect the precision of the detecting instrument. They can be divided into two categories, one category is factors which directly affect the position of reticle image, the other category is factors which affect the calculation the center of reticle image. And the Synthesize error is calculated out. And further distribute the errors reasonably to ensure the accuracy of calibration instruments.

Photoelectric professional students in common universities cultivate way to explore under the background of professional certification

Science.gov (United States)

Sun, Yan-jun; Wang, Li; Leng, Yan-bing

2017-08-01

In view of the engineering education professional certification of specialty construction and the specific requirements of the training system, combining with our school optoelectronic information science and engineering characteristics, analysis of the optoelectronic information science and engineering in our school problems and challenges, to locate the specific professional training objectives. From the service oriented industry demand for talent ability, at the same time, according to the ministry of education professional norms of the development of the photoelectric teaching steering committee, and the professional development and the characteristics of target, to build a set to conform to the goal of cultivating the professional curriculum system. At the same time set up a from fundamental to professional practice teaching system, covers the course experiment, course design, case teaching, comprehensive training, such as graduation design practice. Which implements a whole ability training from the practice of foundation to high-end chain, embodies the training goal emphasize "outstanding practical skills, quality education is distinct culture characteristic. By further speed up the professional construction, professional certification standards to standardize our training process, improved the level of professional training, and improve the comprehensive quality of the graduates and talent of social competitiveness, fostered more professional talents for the country.

Development of Multi-Channel Photoelectric Photometer Using Optical Fiber

Directory of Open Access Journals (Sweden)

Woo-Baik Lee

1993-06-01

Full Text Available We have developed a four-channel photoelectric photometer for the 61cm telescope of Sobaeksan Astronomy Observatory using optical fiber. We observed a standard star with each channel to check the efficiency difference between the channels, and found no differences. To calibrate the observing accuracy and efficiency, we have observed a short period WUMa type eclipsing binary star, BV Dra. Test observations show that the photometer is very stable and the accuracy of the data is also increased. The observing efficiency is very increased compared with that of single channel photometer; at least five times faster than older one in the case of one filter observation.

Electrical and photoelectrical properties of poly(phenyl azomethine furane) thin films devices

Energy Technology Data Exchange (ETDEWEB)

Sharma, G.D. [J.N.V. Univ., Jodhpur (India). Dept. of Phys.; Sandogaker, S.G. [J.N.V. Univ., Jodhpur (India). Dept. of Phys.; Roy, M.S. [Camouflage Division, Defence Laboratory, Jodhpur (Raj.) (India)

1996-05-15

Poly(phenyl azomethine furane) (PPAF), a conjugated system of poly-Schiff base was synthesised by condensation of p-aminobenzene with furane-2-aldehyde. Oxidative polymerization was conducted at 0-5 C temperature, and the polymer formed was found to be soluble in common organic solvent. Optical properties were studied in the UV-visible-IR region. Electrical and photoelectrical properties of Al/PPAF/ITO and Ag/PPAF/ITO sandwich devices were investigated by measuring the steady state photocurrent resulting from illumination. The device Al/PPAF/ITO shows a Schottky barrier at the Al-PPAF interface and ohmic contact at ITO-PPAF interface. The device Ag/PPAF/ITO shows ohmic contact at both interfaces. This behaviour has been explained in terms of P-type conductivity of the PPAF and the formation of a Schottky barrier with the low work function electrode and ohmic contact with the higher work function electrode. Under low forward bias voltage (ITO positive) ohmic conduction is observed while at higher voltage there is space charge-limited conduction (SCLC). The dependence of the photo short-circuit current on illumination intensity was discussed in detail. The C-V characteristics of both devices have also been analysed. (orig.)

CALiPER Report 22.1: Photoelectric Performance of LED MR16 Lamps

Energy Technology Data Exchange (ETDEWEB)

None, None

2015-08-31

This report looks at the photoelectric performance of the same set of lamps assessed in Report 22, using commercially available transformers and dimmers as well as laboratory power supplies providing either AC or DC. The investigation explores several issues related to the testing and use of MR16 lamps in lighting systems and examines the range of performance that is possible for a given lamp model, based on the system to which it is connected.

X-ray attenuation coefficients and photoelectric cross sections of Cu, Fe and Sn for the energy range 3-29 KeV

International Nuclear Information System (INIS)

Wang Dachun; Yang Hua; Luo Pingan; Ding Xunliang; Wang Xinfu; Zhou Hongyu; Shen Xinyin; Zhu Guanghua

1991-08-01

The document contains the following two papers: X-ray attenuation coefficient and photoelectric cross sections of Sn for the Energy Range 3.3 KeV to 29.1 KeV - by Wang Dachun, Yang Hua and Luo Pingan. X-ray attenuation coefficients and photoelectric cross sections of Cu and Fe for the range 3 KeV to 29 KeV - by Wang Dachun, Ding Xunliang, Wang Xinfu, Yang Hua, Zhou Hongyu, Shen Xinyin and Zhu Guanghua. A separate abstract was prepared for each of these papers. Refs, figs and tabs

Unusual photoelectric behaviors of Mo-doped TiO2 multilayer thin films prepared by RF magnetron co-sputtering: effect of barrier tunneling on internal charge transfer

Science.gov (United States)

Yan, B. X.; Luo, S. Y.; Mao, X. G.; Shen, J.; Zhou, Q. F.

2013-01-01

Mo-doped TiO2 multilayer thin films were prepared by RF magnetron co-sputtering. Microstructures, crystallite parameters and the absorption band were investigated with atomic force microscopy, X-ray diffraction and ultraviolet-visible spectroscopy. Internal carrier transport characteristics and the photoelectric property of different layer-assemble modes were examined on an electrochemical workstation under visible light. The result indicates that the double-layer structure with an undoped surface layer demonstrated a red-shifted absorption edge and a much stronger photocurrent compared to the uniformly doped sample, signifying that the electric field implanted at the interface between particles in different layers accelerated internal charge transfer effectively. However, a heavily doped layer implanted at the bottom of the three-layer film merely brought about negative effects on the photoelectric property, mainly because of the Schottky junction existing above the substrate. Nevertheless, this obstacle was successfully eliminated by raising the Mo concentration to 1020 cm-3, where the thickness of the depletion layer fell into the order of angstroms and the tunneling coefficient manifested a dramatic increase. Under this circumstance, the Schottky junction disappeared and the strongest photocurrent was observed in the three-layer film.

RF Photoelectric injectors using needle cathodes

International Nuclear Information System (INIS)

Lewellen, J.W.; Brau, C.A.

2003-01-01

Photocathode RF guns, in various configurations, are the injectors of choice for both current and future applications requiring high-brightness electron beams. Many of these applications, such as single-pass free-electron lasers, require beams with high brilliance but not necessarily high charge per bunch. Field-enhanced photoelectric emission has demonstrated electron-beam current density as high as 10 10 A/m 2 , with a quantum efficiency in the UV that approaches 10% at fields on the order of 10 10 V/m. Thus, the use of even a blunt needle holds promise for increasing cathode quantum efficiency without sacrificing robustness. We present an initial study on the use of needle cathodes in photoinjectors to enhance beam brightness while reducing beam charge. Benefits include lower drive-laser power requirements, easier multibunch operation, lower emittance, and lower beam degradation due to charge-dependent effects in the postinjector accelerator. These benefits result from a combination of a smaller cathode emission area, greatly enhanced RF field strength at the cathode, and the charge scaling of detrimental postinjector linac effects, e.g., transverse wakefields and CSR

RF Photoelectric injectors using needle cathodes

Science.gov (United States)

Lewellen, J. W.; Brau, C. A.

2003-07-01

Photocathode RF guns, in various configurations, are the injectors of choice for both current and future applications requiring high-brightness electron beams. Many of these applications, such as single-pass free-electron lasers, require beams with high brilliance but not necessarily high charge per bunch. Field-enhanced photoelectric emission has demonstrated electron-beam current density as high as 10 10 A/m 2, with a quantum efficiency in the UV that approaches 10% at fields on the order of 10 10 V/m. Thus, the use of even a blunt needle holds promise for increasing cathode quantum efficiency without sacrificing robustness. We present an initial study on the use of needle cathodes in photoinjectors to enhance beam brightness while reducing beam charge. Benefits include lower drive-laser power requirements, easier multibunch operation, lower emittance, and lower beam degradation due to charge-dependent effects in the postinjector accelerator. These benefits result from a combination of a smaller cathode emission area, greatly enhanced RF field strength at the cathode, and the charge scaling of detrimental postinjector linac effects, e.g., transverse wakefields and CSR.

Instability of a double layer and initiation of a photoelectric gas discharge by UV radiation

International Nuclear Information System (INIS)

Meshalkin, E.A.

1991-01-01

At the present time there is no theory or systematic experiments for the conversion of the energy of vacuum uv radiation into current energy in connection with the photoelectric effect in gases. The aim in this work was to study the process by which an SCL is established and to obtain a gas discharge associated with photoemission (a photoelectric gas discharge), similar to the gas discharge in thermal-emission converters, in order to transform optical energy into electrical current. The development of a space-charge layer (SCL) is studied when a metallic target in air or nitrogen at a pressure in the range 10 -3 -10 torr is subjected to UV radiation. A laser plasma was used as the source of the UV radiation, modulated in intensity at a frequency of 75 MHz. It was found that after a period of development in the course of which the potential difference across the SCL can reach 185 V, it drops abruptly. This effect is due to an instability of the SCL which arises because the pressure of the electron gas in the background plasma exceeds the confining pressure of the electric field which penetrates from SCL into the plasma. A photoelectric arc discharge was observed in which the energy of the UV radiation was converted into current energy with an efficiency ∼ 1%. The current was found to be 3.1 A and the power in the load was 10W. Because of the threshold for the occurrence of the instability in the SCL, the potential drop across the SCL could be completely modulated at a frequency of 75 MHz. The amplitude of the HF current reached 0.3 A

Photoelectric equipment type MFS-7 for analyzing oils

International Nuclear Information System (INIS)

Orlova, S.A.; Fridman, M.G.; Kholosha, T.V.; Ezhoda, G.D.; Nechitailov, V.V.

1987-01-01

The authors describe the equipment type MFS-7 which is intended for analyzing used oils for the wear products of motors. The difference between type MFS-7 and its predecessors lies in the application of computer techniques to control the equipment and process the output data; and in the design of the sample container, which allows for two methods of introducing the sample into the discharge. The photoelectric equipment consists of an excitation spectrum source IVS-28, having an ac arc mode and 1.v. spark, a polychoromator, a special sample holder for analyzing liquid samples, an electronic recording apparatus with digital voltmeter type ERU-18 and control computer system Spectr 2.2 based on a minicomputer with its own printer. The type MFS-7 equipment has been tested and put into mass production

Determination of X-ray photoelectric absorption of Ge and Si avoiding solid-state effects

International Nuclear Information System (INIS)

Baltazar-Rodrigues, J.; Cusatis, C.

2001-01-01

X-ray linear attenuation coefficients of germanium and silicon were measured with precision between 0.1% and 0.3% for six characteristic wavelengths: copper, molybdenum and silver K lines. The linear photoelectric absorption coefficients were determined from the values of the measured attenuation coefficients by subtracting the calculated Compton and thermal diffuse scattering involved. It is shown that in order to compare calculated values of X-ray absorption coefficients based on the isolated atom assumption with experimental results obtained from solid samples it is necessary to take into consideration the solid-state effects. Before the measurements the sample's angular positions were scanned to search for Bragg scattering and the measurements of the transmitted intensities were done far from these angular positions. The measurements were performed in three samples of each element with different thickness and in different angular positions for each sample in order to check the consistency of the measured attenuation coefficients. Several instrumental and experimental details were considered in order to achieve the final asserted precision

Experimental investigation on photoelectric properties of ZAO thin film deposited on flexible substrate by magnetron sputtering

Energy Technology Data Exchange (ETDEWEB)

Hao, Ming [School of Mechanical Engineering and Automation, Northeastern University, 3-11 WenHua Rd., 319#, Shenyang, 110004 (China); Liu, Kun, E-mail: kliu@mail.neu.edu.cn [School of Mechanical Engineering and Automation, Northeastern University, 3-11 WenHua Rd., 319#, Shenyang, 110004 (China); Liu, Xinghua [Hubei Aerospace Industry Technology Academe Special Vehicle Technology Center, Wuhan (China); Wang, Dongyang; Ba, Dechun; Xie, Yuanhua; Du, Guangyu; Ba, Yaoshuai [School of Mechanical Engineering and Automation, Northeastern University, 3-11 WenHua Rd., 319#, Shenyang, 110004 (China)

2016-12-01

Highlights: • ZAO thin films were deposited on PET substrate. • A set of experimental parameters were systematically investigated. • Change rule of film photoelectric properties was obtained. • ZAO films with optimal properties were obtained at our working conditions. - Abstract: Transparent conductive ZAO (Zinc Aluminum Oxide) films on flexible substrates have a great potential for low-cost mass-production solar cells. ZAO thin films were achieved on flexible PET (polyethylene terephthalate) substrates by RF magnetron sputtering technology. The surface morphology and element content, the transmittance and the sheet resistance of the films were measured to determine the optical process parameters. The results show that the ZAO thin film shows the best parameters in terms of photoelectric performance including sputtering power, working pressure, sputtering time, substrate temperature (100 W, 1.5 Pa, 60 min, 125 °C). The sheet resistance of 510 Ω and transmittance in visible region of 92% were obtained after characterization. Surface morphology was uniform and compact with a good crystal grain.

Experimental investigation on photoelectric properties of ZAO thin film deposited on flexible substrate by magnetron sputtering

International Nuclear Information System (INIS)

Hao, Ming; Liu, Kun; Liu, Xinghua; Wang, Dongyang; Ba, Dechun; Xie, Yuanhua; Du, Guangyu; Ba, Yaoshuai

2016-01-01

Highlights: • ZAO thin films were deposited on PET substrate. • A set of experimental parameters were systematically investigated. • Change rule of film photoelectric properties was obtained. • ZAO films with optimal properties were obtained at our working conditions. - Abstract: Transparent conductive ZAO (Zinc Aluminum Oxide) films on flexible substrates have a great potential for low-cost mass-production solar cells. ZAO thin films were achieved on flexible PET (polyethylene terephthalate) substrates by RF magnetron sputtering technology. The surface morphology and element content, the transmittance and the sheet resistance of the films were measured to determine the optical process parameters. The results show that the ZAO thin film shows the best parameters in terms of photoelectric performance including sputtering power, working pressure, sputtering time, substrate temperature (100 W, 1.5 Pa, 60 min, 125 °C). The sheet resistance of 510 Ω and transmittance in visible region of 92% were obtained after characterization. Surface morphology was uniform and compact with a good crystal grain.

Relative L-shell photoelectric cross-section measurements in W, Pb and U

Energy Technology Data Exchange (ETDEWEB)

Arora, S K; Allawadhi, K L; Sood, B S [Punjabi Univ., Patiala (India). Nuclear Science Labs.

1981-06-01

Measurements of L-shell photoelectric cross sections in W, Pb and U at K X-ray energies of Nb, Mo, Ag, In, Sn, I, Ba, Ce, Gd and Er have been made. The method yields relative cross sections and is, therefore, simpler and more accurate than those giving absolute values. The problems arising due to the non-monochromatic character of incident and emitted X-rays in the targets have been investigated. The present results show a fairly good agreement with the theoretical predicitions.

Some results concerning the external photoelectric effect and secondary emission; Quelques resultats sur l'effet photoelectrique externe et l'emission secondaire

Energy Technology Data Exchange (ETDEWEB)

Lenouvel, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Ecole normale superieure, 75 - Paris (France)

1967-01-01

The characteristics and limiting possibilities of the various constituent parts of a photoelectric detector are considered. Two methods for illuminating the cathode are described and discussed. The few scattered results concerning the maximum output of cathodes and dynodes are collected together and a tentative explanation is put forward. A comparison is made of three methods for measuring very low light fluxes. (author) [French] Nous degageons les caracteristiques et les possibilites limites des divers elements constitutifs d'un detecteur photoelectrique. Deux solutions d'illumination de la cathode sont decrites et discutees. Les quelques resultats epars sur la limite de debit des cathodes et des dynodes sont rassembles et une interpretation provisoire est esquissee. Trois moyens de mesure des tres faibles flux lumineux sont compares. (auteur)

Photochemical charges separation and photoelectric properties of flexible solar cells with two types of heterostructures

Energy Technology Data Exchange (ETDEWEB)

Liu, Xiangyang, E-mail: lxy081276@126.com, E-mail: yzgu@henu.edu.cn; Wang, Shun; Zheng, Haiwu; Cheng, Xiuying; Gu, Yuzong, E-mail: lxy081276@126.com, E-mail: yzgu@henu.edu.cn [Institute of Microsystems Physics and School of Physics and Electronics, Henan University, Kaifeng 475004 (China)

2015-12-14

Photochemical charges generation, separation, and transport at nanocrystal interfaces are central to energy conversion for solar cells. Here, Zn{sub 2}SnO{sub 4} nanowires/Cu{sub 4}Bi{sub 4}S{sub 9} (ZTO/CBS), ZTO nanowires/CBS-reduced graphene oxide (ZTO/CBS-RGO), and bulk heterojunction (BHJ) solar cells were measured. The signals of steady state and electric field-induced surface photovoltage indicate that RGO with high electron mobility can evidently improve the photovoltaic response. Besides, ZTO/CBS and ZTO/CBS-RGO cells exhibit the excellent performance and the highest efficiencies of 1.2% and 2.8%, respectively. The internal relations of photoelectric properties to some factors, such as film thickness, direct paths, RGO conductive network, energy level matching, etc., were discussed in detail. Qualitative and quantitative analyses further verified the comprehensive effect of RGO and other factors. Importantly, the fine bendable characteristic of BHJ solar cells with excellent efficiency and facile, scalable production gives the as-made flexible solar cells device potential for practical application in future.

Photoelectric UBV and DDO photometry of NGC 5138

International Nuclear Information System (INIS)

Claria, J.J.

1980-01-01

Results of UBV photoelectric photometry in NGC 5138 are presented for 50 stars brighter than 14.0 mag. In addition, four probable red giants were also observed in the DDO system. Sixteen stars previously considered members by Lindoff (1972), were found not to be physically connected with the cluster. NGC 5138 is located 1.80 kpc from the Sun and the visual interstellar absorption determined from the reddened B stars amounts to Asub(v) = 0.75 mag. There of the four red stars observed in the DDO system were found to be cluster members. The mean cyanogen anomaly is = 0.043 +- 0.018(m.e.), which implies that NGC 5138 is richer in CN than the field K giants in the solar neighbourhodd, but poorer than the Hyades giants. The cluster age is estimated to be approx. 1.5 x 10 8 yr. (orig.)

Gamma radiation effects on photorefractive and photoelectric properties of lithium niobate crystals

Energy Technology Data Exchange (ETDEWEB)

Vartanyan, Eh.S.; Ovsepyan, R.K.; Pogosyan, A.R.; Timofeev, A.L.

1984-08-01

Investigations into the gamma radiation effect on the photorefractive aned photoelectric properties of lithium niobate crystals have been carried out for the first time. Gamma irradiation has been found to lead to an increase in the photorefractive sensitivity. The effect of optical decoloration has been discovered for the first time along with photorelaxation currents resulting from radiation center decay under the action of light. It has been shown that an increase of photorefractive sensitivity in gamma-irradiated lithium niobate crystals is caused by a new photorefraction mechanism - photorelaxation currents.

Photoelectric effect photon beam position monitors

International Nuclear Information System (INIS)

Anon.

1991-01-01

Stability of the electron orbit is of critical importance at the NSLS. Many experimenters utilizing the NSLS photon beams can take full advantage of the small transverse dimensions of the source only if the electron orbit variation is kept below 10 to 20% of the transverse electron bunch size. Clearly the first step in a program to stabilize the orbit is to develop position monitors with the required sensitivity, reliability and dynamic range. Of great importance are monitors detecting the photon beams themselves, and also monitors measuring the position of the electron beam. In this section the authors discuss photon beam position monitors utilizing the photoelectric effects, and in the following section the use of capacitively coupled pick-up electrodes to detect electron beam position will be described. In what follows they shall proceed to consider two generic types of monitor geometries (1) Gap monitors, which are designed with the idea that the fringes of the synchrotron radiation will be measured, and the hot or fundamental beam will pass through the monitor unimpeded. (2) Area monitors, which are comprised of two triangular elements nested together similar to the electrodes of a split ion chamber or the diodes described by Siddons and Kraner or Mitsuhashi et al

Laser-assisted preparation and photoelectric properties of grating-structured Pt/FTO thin films

Energy Technology Data Exchange (ETDEWEB)

Ren, Nai-fei, E-mail: rnf_ujs@126.com [School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013 (China); Jiangsu Provincial Key Laboratory of Center for Photon Manufacturing Science and Technology, Jiangsu University, Zhenjiang 212013 (China); Huang, Li-jing, E-mail: lij_huang@126.com [Jiangsu Provincial Key Laboratory of Center for Photon Manufacturing Science and Technology, Jiangsu University, Zhenjiang 212013 (China); School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013 (China); Li, Bao-jia [Jiangsu Provincial Key Laboratory of Center for Photon Manufacturing Science and Technology, Jiangsu University, Zhenjiang 212013 (China); School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013 (China); Zhou, Ming [Jiangsu Provincial Key Laboratory of Center for Photon Manufacturing Science and Technology, Jiangsu University, Zhenjiang 212013 (China); The State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)

2014-09-30

Highlights: • Pt layers were deposited by DC magnetron sputtering on commercial FTO glasses. • Pt/FTO films were irradiated by laser for inducing gratings and annealing. • An ideal grating-structured Pt/FTO film was obtained using a fluence of 1.05 J/cm{sup 2}. • The grating-structured Pt/FTO film exhibited excellent photoelectric properties. • Laser-assisted treatment is effective for improving performance of FTO-based films. - Abstract: In order to improve the transparency and conductivity of commercial fluorine-doped tin oxide (FTO) glass, platinum (Pt) layers were deposited on the FTO film by direct current (DC) magnetron sputtering, followed by being irradiating with a 532 nm nanosecond pulsed laser for the dual purpose of inducing grating structures and annealing. Introducing a Pt layer decreased the average transmittance (400–800 nm) and the sheet resistance of the initial FTO film from 80.2% and 8.4 Ω/sq to 68.6% and 7.9 Ω/sq, respectively. The ideal grating-structured Pt/FTO film was obtained by laser irradiation with a fluence of 1.05 J/cm{sup 2}, and X-ray diffraction (XRD) analysis confirmed that this film underwent optimal annealing. As a result, it exhibited an average transmittance (400–800 nm) of 84.1% and a sheet resistance of 6.8 Ω/sq. These results indicated that laser-assisted treatment combined with introduction of metal layer can effectively improve photoelectric properties of FTO single-layer films.

Photoelectrical stimulation of neuronal cells by an organic semiconductor-electrolyte Interface

DEFF Research Database (Denmark)

Abdullaeva, Oliya S.; Schulz, Matthias; Balzer, Frank

2016-01-01

As a step toward the realization of neuroprosthetics for vision restoration, we follow an electrophysiological patch-clamp approach to study the fundamental photoelectrical stimulation mechanism of neuronal model cells by an organic semiconductor–electrolyte interface. Our photoactive layer...... consisting of an anilino-squaraine donor blended with a fullerene acceptor is supporting the growth of the neuronal model cell line (N2A cells) without an adhesion layer on it and is not impairing cell viability. The transient photocurrent signal upon illumination from the semiconductor–electrolyte layer....... Furthermore, we characterize the morphology of the semiconductor–electrolyte interface by atomic force microscopy and study the stability of the interface in dark and under illuminated conditions....

The effect of Phet Simulation media for physics teacher candidate understanding on photoelectric effect concept

Directory of Open Access Journals (Sweden)

Supurwoko Supurwoko

2017-02-01

Full Text Available Indonesian new Curriculum for senior high school students required student-centered learning. One of the curriculum implementation constraint was the difficulty of providing learning media. PhET simulations media is one of the options that can help implementation of new curriculum on learning. However, the use of this media in Indonesia still needs to be studied comprehensively. The learning was conducted on students of physics education Study Program in sebelas maret university in 2013. The sample consisted of 62 students that was taking quantum physics course. The method that was used in the research was descriptive qualitative.  The method that was used in learning was demonstration’s method that used PhET media and accompanied by a question and answer and groups discussion. The data was collected using multiple choice test and interview through email. We found that any students still did not understand about photoelectric effect concept. They were confused when asked about the thick material and cross section of the targets as related with the regardless of electrons in the photoelectric effect event. Other than that, the concept of the waves as a particle and its relation with the kinetic energy of the electrons was not understood by most students.

The present situation of photo-electric plants in the Sahel zone: Possibilities and limits of a marketing strategy using the example of the Niger. Zur gegenwaertigen Situation photovoltaischer Anlagen in der Sahelzone: Moeglichkeiten und Grenzen einer Vermarktungsstrategie am Beispiel des Niger

Energy Technology Data Exchange (ETDEWEB)

Hempel, C. (GTZ - Sonderenergieprogramm Niger, Niamey (Niger))

1993-01-01

The report is aimed at three targets: First one deals with the meteorological data as the basis for the technical design of photo-electric plants, secondly there is a short survey of the present situation of photo-electrics in Nigeria (referring also to other Sahel countries), and thirdly, the possibilities and limits of a marketing strategy for photo-electric plants are sketched out for this region. (orig.)

Application and research of artificial water mist on photoelectric interference

Science.gov (United States)

He, Yuejun; Ren, Baolin

2018-04-01

Water mist is a new type of photoelectric interfering material. It can exert a strong interference and shielding effect on infrared light, laser and radar wave through scattering, reflection, refraction and absorption. Based on this, this paper illustrates the application of an artificial high pressure water mist technology in infrared interference system. First, the operating principle of the infrared interference system is introduced. Next, the design principle of self-excited rotary vortex nozzle, the key part of the system, is elaborated. Then, the calculation of the main control parameters of the system is clarified. In the end, the paper verifies interference and shielding effect of the system by experiment. Experiment shows that the interference system can significantly reduce infrared signature of the target, featuring excellent infrared interference performance and high practical value.

Protection of High Ceiling Nuclear Facilities Using Photoelectric Sensors and Infrared Fire Detectors

International Nuclear Information System (INIS)

Wadoud, A.A.; El Eissawi, H.M.; Saleh, A.A.

2017-01-01

A variety of different security systems and components are commercially available and widely used. Before implementing a security system, it is important to understand the characteristics and requirements of the facility area to be protected. Technology and manufacturers of security devices are rapidly changing. It is necessary to use optimal security equipment suitable for the surrounding environment of the facility to be protected. Several security sensors can be used to protect the nuclear facilities, such as passive infrared detectors and glass breakage sensors, vibration detectors, and microwave sensors. This work introduces technical specifications, operation and method of installation for these detectors in nuclear facilities. Also a comparative study of different security sensors or equipment is provided. The photoelectric detectors and infrared fire beam smoke detectors are reliable, suitable and advanced security equipment. They can be used in special cases because of their advantages, this includes their long ranges and accuracy in performance. This paper presents a new concept for adapting the use infrared optical fire beam smoke detector as intrusion detection equipment in high ceiling buildings or towering height facilities. This is in addition to their main function, namely fire detection.The paper also provides a study for their types and installation method. Focus is made on the installation and operation method for two advanced security systems, and wireless control circuit for the overall system operation

Photoelectric effect from observer's mathematics point of view

Science.gov (United States)

Khots, Boris; Khots, Dmitriy

2014-12-01

When we consider and analyze physical events with the purpose of creating corresponding models we often assume that the mathematical apparatus used in modeling is infallible. In particular, this relates to the use of infinity in various aspects and the use of Newton's definition of a limit in analysis. We believe that is where the main problem lies in contemporary study of nature. This work considers Physical aspects in a setting of arithmetic, algebra, geometry, analysis, topology provided by Observer's Mathematics (see www.mathrelativity.com). Certain results and communications pertaining to solution of these problems are provided. In particular, we prove the following Theorems, which give Observer's Mathematics point of view on Einstein photoelectric effect theory and Lamb-Scully and Hanbury-Brown-Twiss experiments: Theorem 1. There are some values of light intensity where anticorrelation parameter A ∈ [0,1). Theorem 2. There are some values of light intensity where anticorrelation parameter A = 1. Theorem 3. There are some values of light intensity where anticorrelation parameter A > 1.

An Experimental and Theoretical Investigation of the Electronic Structures and Photoelectrical Properties of Ethyl Red and Carminic Acid for DSSC Application

Directory of Open Access Journals (Sweden)

Chaofan Sun

2016-10-01

Full Text Available The photoelectrical properties of two dyes—ethyl red and carminic acid—as sensitizers of dye-sensitized solar cells were investigated in experiments herein described. In order to reveal the reason for the difference between the photoelectrical properties of the two dyes, the ground state and excited state properties of the dyes before and after adsorbed on TiO2 were calculated via density functional theory (DFT and time-dependent DFT (TDDFT. The key parameters including the light harvesting efficiency (LHE, the driving force of electron injection ( Δ G inject and dye regeneration ( Δ G regen , the total dipole moment ( μ normal , the conduction band of edge of the semiconductor ( Δ E CB , and the excited state lifetime (τ were investigated, which are closely related to the short-circuit current density ( J sc and open circuit voltage ( V oc . It was found that the experimental carminic acid has a larger J sc and V oc , which are interpreted by a larger amount of dye adsorbed on a TiO2 photoanode and a larger Δ G regen , excited state lifetime (τ, μ normal , and Δ E CB . At the same time, chemical reactivity parameters illustrate that the lower chemical hardness (h and higher electron accepting power (ω+ of carminic acid have an influence on the short-circuit current density. Therefore, carminic acid shows excellent photoelectric conversion efficiency in comparison with ethyl red.

Time improvement of photoelectric effect calculation for absorbed dose estimation

International Nuclear Information System (INIS)

Massa, J M; Wainschenker, R S; Doorn, J H; Caselli, E E

2007-01-01

Ionizing radiation therapy is a very useful tool in cancer treatment. It is very important to determine absorbed dose in human tissue to accomplish an effective treatment. A mathematical model based on affected areas is the most suitable tool to estimate the absorbed dose. Lately, Monte Carlo based techniques have become the most reliable, but they are time expensive. Absorbed dose calculating programs using different strategies have to choose between estimation quality and calculating time. This paper describes an optimized method for the photoelectron polar angle calculation in photoelectric effect, which is significant to estimate deposited energy in human tissue. In the case studies, time cost reduction nearly reached 86%, meaning that the time needed to do the calculation is approximately 1/7 th of the non optimized approach. This has been done keeping precision invariant

Manufacturing technologies for photovoltaics and possible means of their development in Russia (Review). Part 1: General approach to the development of photoelectric converters and basic silicon technologies

Science.gov (United States)

Tarasenko, A. B.; Popel', O. S.

2015-11-01

The state and key tendencies of the development of basic technologies for manufacture of photoelectric converters (PECs) in the world are considered, and their advantages and disadvantages are discussed. The first part of the review gives short information on the development of photovoltaics in the world and planes of the development of solar power plants in Russia. Total power of photoelectric plants operating in various countries in 2015 exceeded 150 GW and increased in the last ten years with a rate of approximately 50% per year. Russia made important state decisions on the support of the development of renewable power engineering and developed mechanisms, which were attractive for business, on the stimulation of building of the network of solar power plants with a total power to 1.5 GW in the country to 2020. At the same time, the rigid demands are made with respect to the localization of the production of components of these plants that opens new abilities for the development of the domestic production of photovoltaics manufacture. Data on the efficiency of PECs of various types that are attained in the leading laboratories of the world are given. Particular emphasis has been placed on the consideration of basic silicon technologies of PEC manufacture, which had the widest commercial application. The basic methods for production of polycrystalline silicon and making single-crystal and multicrystal silicon are described. Fundamentals of making techniques for plates, PECs, and photoelectric modules based on single-crystal and polycrystalline silicon are considered. The second part will be devoted to modifications of manufacturing techniques for photoelectric converters, enhancement methods for contact structures, and recommendations of authors with respect to the choice of prospective technologies for the expansion of PEC production in Russia. It will involve formulations and substantiations of the most promising lines of the development of photoelectric

Multipulse nanosecond laser irradiation of silicon for the investigation of surface morphology and photoelectric properties

Science.gov (United States)

Sardar, Maryam; Chen, Jun; Ullah, Zaka; Jelani, Mohsan; Tabassum, Aasma; Cheng, Ju; Sun, Yuxiang; Lu, Jian

2017-12-01

We irradiate the single crystal boron-doped silicon (Si) with different number of laser pulses at constant fluence (7.5 J cm-2) in ambient air using Nd:YAG laser and examine its surface morphology and photoelectric properties in details. The results obtained from optical micrographs reveal the increase in heat affected zone (HAZ) and melted area of laser irradiated Si with increasing number of laser pulses. The SEM micrographs evidence the formation of various surface morphologies like laser induced periodic surface structures, crater, microcracks, clusters, cavities, pores, trapped bubbles, nucleation sites, micro-bumps, redeposited material and micro- and nano-particles on the surface of irradiated Si. The surface profilometry analysis informs that the depth of crater is increased with increase in number of incident laser pulses. The spectroscopic ellipsometry reveals that the multipulse irradiation of Si changes its optical properties (refractive index and extinction coefficient). The current-voltage (I-V) characteristic curves of laser irradiated Si show that although the multipulse laser irradiation produces considerable number of surface defects and damages, the electrical properties of Si are well sustained after the multipulse irradiation. The current findings suggest that the multipulse irradiation can be an effective way to tune the optical properties of Si for the fabrication of wide range of optoelectronic devices.

CALiPER Report 22.1: Photoelectric Performance of LED MR16 Lamps

Energy Technology Data Exchange (ETDEWEB)

Royer, Michael P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Poplawski, Michael E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Brown, Charles C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Merzouk, Massine B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-09-01

This report is a follow-up to CALiPER Application Summary Report 22, which investigated the photometric performance of LED MR16 lamps. The initial report found that many of the LED MR16 lamps did not perform as required by ENERGY STAR based on their equivalency claims, although they generally did provide substantial efficacy advantages compared to halogen MR16 lamps. All testing was completed using laboratory power supplies, with all but one product tested at 12 V AC. In contrast, this report examined the photoelectric performance of the same set of lamps, using commercially available transformers and dimmers as well as laboratory power supplies providing both AC and DC power.

Exploration on practice teaching reform of Photoelectric Image Processing course under applied transformation

Science.gov (United States)

Cao, Binfang; Li, Xiaoqin; Liu, Changqing; Li, Jianqi

2017-08-01

With the further applied transformation of local colleges, teachers are urgently needed to make corresponding changes in the teaching content and methods from different courses. The article discusses practice teaching reform of the Photoelectric Image Processing course in the Optoelectronic Information Science and Engineering major. The Digital Signal Processing (DSP） platform is introduced to the experimental teaching. It will mobilize and inspire students and also enhance their learning motivation and innovation through specific examples. The course via teaching practice process has become the most popular course among students, which will further drive students' enthusiasm and confidence to participate in all kinds of electronic competitions.

Measurement of L-shell photoelectric cross sections in high Z elements at 37 and 74 keV

Energy Technology Data Exchange (ETDEWEB)

Allawadhi, K L; Ghumman, B S; Sood, B S [Punjabi Univ., Patiala (India). Nuclear Science Labs.

1977-05-01

L-shell photoelectric cross section measurements have been made at 36.818 and 74.409 keV for four elements in the range 81<=Z<=92. The measurements at 74.409 keV are found to agree with theory, within experimental uncertainties, but the experimental values at 36.818 keV are found to be higher than the theoretical predictions. The possible reasons for the observed discrepancy are discussed.

The fundamental parameter approach of quantitative XRFA- investigation of photoelectric absorption coefficients

International Nuclear Information System (INIS)

Shaltout, A.

2003-06-01

The present work describes some actual problems of quantitative x-ray fluorescence analysis by means of the fundamental parameter approach. To perform this task, some of the main parameters are discussed in detail. These parameters are photoelectric cross sections, coherent and incoherent scattering cross sections, mass absorption cross sections and the variation of the x-ray tube voltage. Photoelectric cross sections, coherent and incoherent scattering cross sections and mass absorption cross sections in the energy range from 1 to 300 keV for the elements from Z=1 to 94 considering ten different data bases are studied. These are data bases given by Hubbell, McMaster, Mucall, Scofield, Xcom, Elam, Sasaki, Henke, Cullen and Chantler's data bases. These data bases have been developed also for an application in fundamental parameter programs for quantitative x-ray analysis (Energy Dispersive X-Ray Fluorescence Analysis (EDXRFA), Electron Probe Microanalysis (EPMA), X-Ray Photoelectron Spectroscopy (XPS) and Total Electron Yield (TEY)). In addition a comparison is performed between different data bases. In McMaster's data base, the missing elements (Z=84, 85, 87, 88, 89, 91, and 93) are added by using photoelectric cross sections of Scofield's data base, coherent as well as incoherent scattering cross sections of Elam's data base and the absorption edges of Bearden. Also, the N-fit coefficients of the elements from Z=61 to 69 are wrong in McMaster data base, therefore, linear least squares fits are used to recalculate the N-fit coefficients of these elements. Additionally, in the McMaster tables the positions of the M- and N-edges of all elements with the exception of the M1- and N1- edges are not defined as well as the jump ratio of the edges. In the present work, the M- and N-edges and the related jump ratios are calculated. To include the missing N-edges, Bearden's values of energy edges are used. In Scofield's data base, modifications include check and correction

Measured energy dependence of L-shell photoelectric cross sections of lead in the energy region 17-50 keV

Energy Technology Data Exchange (ETDEWEB)

Arora, S K; Allawadhi, K L; Sood, B S [Punjabi Univ., Patiala (India). Nuclear Science Labs.

1980-08-28

The energy dependence of L-shell photoelectric cross sections for lead in the energy region 17-50 keV has been investigated. The method utilises external conversion x-rays as the source of photons and it yields relative rather than absolute cross sections, but is simpler and more accurate. The results show fairly good agreement with theory.

Transparent Cu4O3/ZnO heterojunction photoelectric devices

Science.gov (United States)

Kim, Hong-Sik; Yadav, Pankaj; Patel, Malkeshkumar; Kim, Joondong; Pandey, Kavita; Lim, Donggun; Jeong, Chaehwan

2017-12-01

The present article reports the development of flexible, self-biased, broadband, high speed and transparent heterojunction photodiode, which is essentially important for the next generation electronic devices. We grow semitransparent p-type Cu4O3 using the reactive sputtering method at room temperature. The structural and optical properties of the Cu4O3 film were investigated by using the X-ray diffraction and UV-visible spectroscopy, respectively. The p-Cu4O3/n-ZnO heterojunction diode under dark condition yields rectification behavior with an extremely low saturation current value of 1.8 × 10-10 A and a zero bias photocurrent under illumination condition. The transparent p-Cu4O3/n-ZnO heterojunction photodetector can be operated without an external bias, due to the light-induced voltage production. The metal oxide heterojunction based on Cu4O3/ZnO would provide a route for the transparent and flexible photoelectric devices, including photodetectors and photovoltaics.

FY 1974 report on the results of the Sunshine Project. Study of the hydrogen production technology mainly using photoconductor; 1974 nendo hikari handotai wo shutai to suru suiso seizo gijutsu no kenkyu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1975-05-28

Among semiconductor materials which absorb solar light and produce great photoelectromotive force, materials usable to the electrode of photoelectric cell were sought, the photoelectrode reaction of various electrode materials was investigated, and the photosensitization phenomenon in the solar light region was studied. As to electrode materials, semiconductor materials were sought which have a characteristic of band gap of 1-3eV, and the photosensitization polarization characteristic of a part of the semiconductor materials was measured. Concerning photoelectric cells, the photoelectric cell characteristic was measured by the combination of semiconductor electrode, for the study of the structure of photoelectric cell such as kinds, combination, etc. of electrode materials. As electrode materials, various semiconductors were acquired such as TiO{sub 2}, CdS, GaP, GaAs, Si, Ge, etc., and the electrochemical base photoelectrode characteristic under light irradiation was measured. It was confirmed that GaP and GaAs have good photosensitization polarization characteristics. As the result of the measurement of photoelectric cell characteristics, n-type GaP and n-type GaAs showed good characteristics to anode, and p-type GaP and p-type GaAs to cathode. It was confirmed that there is a possibility of hydrogen production in the solar light wavelength region by the measurement of photoelectric cell characteristics of xenon light and the filter penetration light of xenon light. (NEDO)

Photoelectrical Properties and Energetical Structure of Thin Films of Indandione Derivatives

Directory of Open Access Journals (Sweden)

Maira INDRIKOVA

2011-07-01

Full Text Available A sandwich type structure of two dimetilaminobenziliden-1,3-indandione (DMABI derivatives placed between metal electrodes was made to investigate the photoelectrical properties of these derivatives. DMABI is an organic isolator with a wide energy gap and high quantum efficiency of the photogeneration, DMABI derivatives have received also considerable attention because of its large dipole moment and optical nonlinearities. Besides, since it is a photosensitive material, its use in solar systems is very promising. The energy gap of each material and combined system was observed from the spectral dependence of the quantum efficiency of the photoconductivity and results are compared with results of oxidation and reduction potential of the materials. The values showed a good correlation between experimental data of the photoconductivity and voltamperometry and calculated data of the HOMO and LUMO levels of the molecules.http://dx.doi.org/10.5755/j01.ms.17.2.480

Validation of cross sections for Monte Carlo simulation of the photoelectric effect

CERN Document Server

Han, Min Cheol; Pia, Maria Grazia; Basaglia, Tullio; Batic, Matej; Hoff, Gabriela; Kim, Chan Hyeong; Saracco, Paolo

2016-01-01

Several total and partial photoionization cross section calculations, based on both theoretical and empirical approaches, are quantitatively evaluated with statistical analyses using a large collection of experimental data retrieved from the literature to identify the state of the art for modeling the photoelectric effect in Monte Carlo particle transport. Some of the examined cross section models are available in general purpose Monte Carlo systems, while others have been implemented and subjected to validation tests for the first time to estimate whether they could improve the accuracy of particle transport codes. The validation process identifies Scofield's 1973 non-relativistic calculations, tabulated in the Evaluated Photon Data Library(EPDL), as the one best reproducing experimental measurements of total cross sections. Specialized total cross section models, some of which derive from more recent calculations, do not provide significant improvements. Scofield's non-relativistic calculations are not surp...

Photoelectrical Stimulation of Neuronal Cells by an Organic Semiconductor-Electrolyte Interface.

Science.gov (United States)

Abdullaeva, Oliya S; Schulz, Matthias; Balzer, Frank; Parisi, Jürgen; Lützen, Arne; Dedek, Karin; Schiek, Manuela

2016-08-23

As a step toward the realization of neuroprosthetics for vision restoration, we follow an electrophysiological patch-clamp approach to study the fundamental photoelectrical stimulation mechanism of neuronal model cells by an organic semiconductor-electrolyte interface. Our photoactive layer consisting of an anilino-squaraine donor blended with a fullerene acceptor is supporting the growth of the neuronal model cell line (N2A cells) without an adhesion layer on it and is not impairing cell viability. The transient photocurrent signal upon illumination from the semiconductor-electrolyte layer is able to trigger a passive response of the neuronal cells under physiological conditions via a capacitive coupling mechanism. We study the dynamics of the capacitive transmembrane currents by patch-clamp recordings and compare them to the dynamics of the photocurrent signal and its spectral responsivity. Furthermore, we characterize the morphology of the semiconductor-electrolyte interface by atomic force microscopy and study the stability of the interface in dark and under illuminated conditions.

[Objective non-contact method of study of the color of the human skin integument by use of a photoelectric colorimeter].

Science.gov (United States)

Gruzdeva, N I; Zherebtsov, L D; Vasilevskiĭ, V K; Vremzen, S A

1975-04-01

The authors describe a method of determination of the colour of the skin in man based on the use of contactless photoelectric colorimeter made especially for this purpose. The mean normal values of the indices of the skin colour of the anterior and the posterior surface of the arm in 45 men and 35 women of the Europeoid race under normal conditions are presented.

Mass production and photoelectric performances of P and Al Co-doped ZnO nanocrystals under different cooling post-processes

International Nuclear Information System (INIS)

Deng, Ya-Juan; Lu, Yi; Liu, Jin-Ku; Yang, Xiao-Hong

2015-01-01

The phosphorus and aluminum co-doped in zinc oxide (ZnO) called PAZO nano-crystals (NCs) have been mass synthesized by a combustion method, which shows a preferable photocatalytic capability and conductive ability. This article focuses on the properties of PAZO NCs experienced by three cooling-down aftertreatments, which were the normalizing, quenching and annealing process, respectively. The influences of different cooling processes on the photocatalytic and conductive performances are discussed in details. From the research, we found the quenched-PAZO NCs showed the most unappealing photocatalysis and conductivity, because excessive defects as the recombination center of electron–hole pairs were generated in the quenching process. - Graphical abstract: This research focuses on the PAZO NCs experienced by different cooling-down aftertreatments, which were the normalizing, quenching and annealing process, respectively. The quenched-PAZO NCs had the most unappealing photocatalysis and conductivity, because of generating excessive defects as the recombination center of electron–hole pairs in the quenching process. - Highlights: • We presented a method to mass synthesize co-doped P and Al in ZnO nanocrystals. • The PAZO NCs have novel photoelectric performances. • The cooling post-process influence on the photoelectric properties was studied. • The excessive defects decline the photocatalytic and conductive activities

Electromagnetic Spectrum Analysis and Its Influence on the Photoelectric Conversion Efficiency of Solar Cells.

Science.gov (United States)

Hu, Kexiang; Ding, Enjie; Wangyang, Peihua; Wang, Qingkang

2016-06-01

The electromagnetic spectrum and the photoelectric conversion efficiency of the silicon hexagonal nanoconical hole (SiHNH) arrays based solar cells is systematically analyzed according to Rigorous Coupled Wave Analysis (RCWA) and Modal Transmission Line (MTL) theory. An ultimate efficiency of the optimized SiHNH arrays based solar cell is up to 31.92% in consideration of the absorption spectrum, 4.52% higher than that of silicon hexagonal nanoconical frustum (SiHNF) arrays. The absorption enhancement of the SiHNH arrays is due to its lower reflectance and more supported guided-mode resonances, and the enhanced ultimate efficiency is insensitive to bottom diameter (D(bot)) of nanoconical hole and the incident angle. The result provides an additional guideline for the nanostructure surface texturing fabrication design for photovoltaic applications.

THE FLOCCULATION MAXIMUM (pH) OF FIBRINOGEN AND SOME OTHER BLOOD-CLOTTING REAGENTS. (RELATIVE TURBIDIMETRY WITH THE EVELYN PHOTOELECTRIC COLORIMETER).

Science.gov (United States)

Ferguson, J H

1942-03-20

By means of a novel adaptation of the Evelyn photoelectric colorimeter to the measurement of relative turbidities, the question of the flocculation maximum (F.M.) in acetate buffer solutions of varying pH and salt content has been studied on (a) an exceptionally stable prothrombin-free fibrinogen and its solutions after incipient thermal denaturation and incomplete tryptic proteolysis, (b) plasma, similarly treated, (c) prothrombin, thrombin, and (brain) thromboplastin solutions. All the fibrinogens show a remarkable uniformity of the precipitation pattern, viz. F.M. =4.7 (+/-0.2) pH in salt-containing buffer solutions and pH = 5.3 (+/-0.2) in salt-poor buffer (N/100 acetate). The latter approximates the isoelectric point (5.4) obtained by cataphoresis (14). There is no evidence that denaturation or digestion can produce any "second maximum." The data support the view that fibrin formation (under the specific influence of thrombin) is intrinsically unrelated to denaturation and digestion phenomena, although all three can proceed simultaneously in crude materials. A criticism is offered, therefore, of Wöhlisch's blood clotting theory. Further applications of the photoelectric colorimeter to coagulation problems are suggested, including kinetic study of fibrin formation and the assay of fibrinogen, with a possible sensitivity of 7.5 mg. protein in 100 cc. solution.

Photoelectric characteristics of diodes in prototype photosensitive pixels for a monolithic array infrared photodetector

Energy Technology Data Exchange (ETDEWEB)

Sorochkin, A. V., E-mail: alexandersm@mail.ru; Varavin, V. S.; Predein, A. V.; Sabinina, I. V.; Yakushev, M. V. [Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation)

2012-04-15

Test photodiodes in the form of mesa structures with different areas from 30 Multiplication-Sign 30 to 100 Multiplication-Sign 100 {mu}m in size are fabricated based on a Cd{sub x}Hg{sub 1-x}Te/Si structure at x = 0.235, grown by molecular-beam epitaxy (MBE). The current-voltage characteristics of the diodes are measured in the dark and under background light conditions. The experimental results are compared with theoretical calculations. It is found that the dependence of the photodiode photocurrent and dark current on the mesa structure size appears in the mesa size ranges from 30 Multiplication-Sign 30 to 80 Multiplication-Sign 80 {mu}m. The dark current decreases and the photocurrent increases with decreasing mesa size. The mechanisms affecting the behavior of current-voltage characteristics are discussed.

Favorable ultraviolet photoelectric effects in TbMnO3/Nb-SrTiO3 heterostructures

KAUST Repository

Jin, Kexin

2014-12-01

The rectifying properties and ultraviolet photoelectric effects in TbMnO3/Nb-doped SrTiO3 heterostructures have been investigated. The ideality factors and the diffusion voltages obtained from the current-voltage curves nonlinearly decrease with increasing the temperature. It is observed that the maximum photovoltaic values of the heterostructure irradiated by the 365 nm (2.6 mW/mm2) and 248 nm (0.71 mJ/mm2) lights are about 0.121 V and 0.119 V at T=300 K, respectively. The relations between the relaxation of photovoltages after the irradiation and the power intensity are revealed. These results suggest the potential applications in the development of ultraviolet detectors using oxides-based heterostructures.

Sliding mode control of photoelectric tracking platform based on the inverse system method

Directory of Open Access Journals (Sweden)

Yao Zong Chen

2016-01-01

Full Text Available In order to improve the photoelectric tracking platform tracking performance, an integral sliding mode control strategy based on inverse system decoupling method is proposed. The electromechanical dynamic model is established based on multi-body system theory and Newton-Euler method. The coupled multi-input multi-output (MIMO nonlinear system is transformed into two pseudo-linear single-input single-output (SISO subsystems based on the inverse system method. An integral sliding mode control scheme is designed for the decoupled pseudo-linear system. In order to eliminate system chattering phenomenon caused by traditional sign function in sliding-mode controller, the sign function is replaced by the Sigmoid function. Simulation results show that the proposed decoupling method and the control strategy can restrain the influences of internal coupling and disturbance effectively, and has better robustness and higher tracking accuracy.

Graphene-insulator-semiconductor capacitors as superior test structures for photoelectric determination of semiconductor devices band diagrams

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K. Piskorski

2018-05-01

Full Text Available We report on the advantages of using Graphene-Insulator-Semiconductor (GIS instead of Metal-Insulator-Semiconductor (MIS structures in reliable and precise photoelectric determination of the band alignment at the semiconductor-insulator interface and of the insulator band gap determination. Due to the high transparency to light of the graphene gate in GIS structures large photocurrents due to emission of both electrons and holes from the substrate and negligible photocurrents due to emission of carriers from the gate can be obtained, which allows reliable determination of barrier heights for both electrons, Ee and holes, Eh from the semiconductor substrate. Knowing the values of both Ee and Eh allows direct determination of the insulator band gap EG(I. Photoelectric measurements were made of a series of Graphene-SiO2-Si structures and an example is shown of the results obtained in sequential measurements of the same structure giving the following barrier height values: Ee = 4.34 ± 0.01 eV and Eh = 4.70 ± 0.03 eV. Based on this result and results obtained for other structures in the series we conservatively estimate the maximum uncertainty of both barrier heights estimations at ± 0.05 eV. This sets the SiO2 band gap estimation at EG(I = 7.92 ± 0.1 eV. It is shown that widely different SiO2 band gap values were found by research groups using various determination methods. We hypothesize that these differences are due to different sensitivities of measurement methods used to the existence of the SiO2 valence band tail.

PERSPECTIVE TRANSPORT-POWER SYSTEM BASED ON THE INTEGRATION OF MAGLEV-TECHNOLOGY AND DISTRIBUTED PHOTO-ELECTRIC STATION

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V. O. Dzenzerskiy

2018-02-01

Full Text Available Purpose. The research main purpose is the perfection of magnetolevitating technology on electrodynamic suspension and providing its functioning on the base of ecologically rational energy systems. It means creation of the MAGLEV transport-power system which uses renewable energy sources (in particular, photoelectric converters and is connected to national/local networks as an energy user and producer simultaneously. Methodology. Conducted research, analysis and summary conclusions are based both on the results of works on the given subject, and own works of authors. The methods of systems analysis and computer design of components of the large cyber-physical transport-power system were used during research conducting. Findings. The physical-technical foundations of conception of the perspective transport-power system, which includes high-speed ground vehicle on electrodynamic suspension and distributed photo-electric energy complex are developed. The adapt to the performance of the given transport type and guaranteeing its safe functioning in any weather terms. Originality. For the first time authors substantiated the possibility for creation of single transport complex uniting the speed magnetolevitating system and distributed power supply system on the base of sun energy. It is simultaneously the inalienable part of the precision fast-acting control system, working in the real-time mode. Practical value. The offered scientific-technical solution allows on the base of renewable energy source to solve the problems of power supply and a high-speed transport control. Due to the inclusion of the distributed power supply system into local intellectual networks on the SMART-grid technology it gives the possibility to optimize energy consumption of territories neighboring to high-speed way.

Graphene-insulator-semiconductor capacitors as superior test structures for photoelectric determination of semiconductor devices band diagrams

Science.gov (United States)

Piskorski, K.; Passi, V.; Ruhkopf, J.; Lemme, M. C.; Przewlocki, H. M.

2018-05-01

We report on the advantages of using Graphene-Insulator-Semiconductor (GIS) instead of Metal-Insulator-Semiconductor (MIS) structures in reliable and precise photoelectric determination of the band alignment at the semiconductor-insulator interface and of the insulator band gap determination. Due to the high transparency to light of the graphene gate in GIS structures large photocurrents due to emission of both electrons and holes from the substrate and negligible photocurrents due to emission of carriers from the gate can be obtained, which allows reliable determination of barrier heights for both electrons, Ee and holes, Eh from the semiconductor substrate. Knowing the values of both Ee and Eh allows direct determination of the insulator band gap EG(I). Photoelectric measurements were made of a series of Graphene-SiO2-Si structures and an example is shown of the results obtained in sequential measurements of the same structure giving the following barrier height values: Ee = 4.34 ± 0.01 eV and Eh = 4.70 ± 0.03 eV. Based on this result and results obtained for other structures in the series we conservatively estimate the maximum uncertainty of both barrier heights estimations at ± 0.05 eV. This sets the SiO2 band gap estimation at EG(I) = 7.92 ± 0.1 eV. It is shown that widely different SiO2 band gap values were found by research groups using various determination methods. We hypothesize that these differences are due to different sensitivities of measurement methods used to the existence of the SiO2 valence band tail.

The Interplay between Radiation Pressure and the Photoelectric Instability in Optically Thin Disks of Gas and Dust

Science.gov (United States)

Richert, Alexander J. W.; Lyra, Wladimir; Kuchner, Marc J.

2018-03-01

In optically thin disks, dust grains are photoelectrically stripped of electrons by starlight, heating nearby gas and possibly creating a dust clumping instability—the photoelectric instability (PeI)—that significantly alters global disk structure. In the current work, we use the Pencil Code to perform the first numerical models of the PeI that include stellar radiation pressure on dust grains in order to explore the parameter regime in which the instability operates. In some models with low gas and dust surface densities, we see a variety of dust structures, including sharp concentric rings. In the most gas- and dust-rich models, nonaxisymmetric clumps, arcs, and spiral arms emerge that represent dust surface density enhancements of factors of ∼5–20. In one high gas surface density model, we include a large, low-order gas viscosity and find that it observably smooths the structures that form in the gas and dust, suggesting that resolved images of a given disk may be useful for deriving constraints on the effective viscosity of its gas. Our models show that radiation pressure does not preclude the formation of complex structure from the PeI, but the qualitative manifestation of the PeI depends strongly on the parameters of the system. The PeI may provide an explanation for unusual disk morphologies, such as the moving blobs of the AU Mic disk, the asymmetric dust distribution of the 49 Ceti disk, and the rings and arcs found in the HD 141569A disk.

Theory of the photoelectric effect assisted by an elliptically polarized laser field

International Nuclear Information System (INIS)

Li Shumin; Jentschura, Ulrich D

2009-01-01

The laser-assisted photoelectric effect in atomic hydrogen is investigated for linear, circular and general elliptic polarizations. The perturbative dressed state of the atom in an elliptically polarized nonresonant laser field is derived in the velocity gauge. The continuum state of the ejected electron is described by a Coulomb-Volkov wavefunction. Numerical results show that the ionization cross section by a vacuum ultraviolet photon is enhanced at high laser field intensities and low frequencies. At small and extremely large scattering angles (measured with respect to the wave vector of the incoming vacuum ultraviolet photon), the process for emitting a laser photon is predominant, while at medium angles, the result favours the process without a laser photon exchange. The dependence of the results on the laser polarization and on various geometries is studied, and an interesting pattern is found for the dependence on the frequency of the dressing laser; an intuitive explanation is offered.

Photoelectric effect experiment for understanding the concept of quantization of radiation energy

Directory of Open Access Journals (Sweden)

Yeimy Gerardine Berrios Saavedra

2016-09-01

Full Text Available This study forms part of research on the teaching of physics. The question that directed it was: How a proposed classroom, based on the photoelectric effect experiment helps pres-service teachers of physics of the Universidad Pedagógica Nacional to expand their understanding of the concept of quantization energy of radiation? The construction of the theoretical framework developed on the one hand, with scientific ideas about the quantization of energy, and moreover, with the educational proposals of teaching for understanding. This pedagogical approach was guided by the investigative gaze of the study methodology based on design, taking as main element the use of learning tools such as the task to Predict, Experiment and Explain (PEE. It was found that these tasks fomented the initial understandings of students about the concept, while they enriched and transformed progressively their models and scientific ideas, promoting aspects of scientific work in developing curiosity, imagination and motivation.

Linear surface photoelectric effect of gold in intense laser field as a possible high-current electron source

International Nuclear Information System (INIS)

Farkas, G.; Horvath, Z.G.; Toth, C.; Fotakis, C.; Hontzopoulos, E.

1987-01-01

Investigations were conducted on radiation-induced electron emission processes on a gold target surface with a high-intensity (2 MW/cm 2 ) KrF laser (λ = 248 nm). The single photon surface photoelectric emission obtained can be used for high-current density electron sources. The measured polarization dependence of electron current shows the dominance of the surface-type effect over that of the volume type, thereby making it possible to optimize the short, high-density electron current creation conditions. The advantage of the grazing light incidence and the multiphoton photoeffect giving rise to a 500 A/cm 2 electron current has been demonstrated

The Schrödinger Equation, the Zero-Point Electromagnetic Radiation, and the Photoelectric Effect

Science.gov (United States)

França, H. M.; Kamimura, A.; Barreto, G. A.

2016-04-01

A Schrödinger type equation for a mathematical probability amplitude Ψ( x, t) is derived from the generalized phase space Liouville equation valid for the motion of a microscopic particle, with mass M and charge e, moving in a potential V( x). The particle phase space probability density is denoted Q( x, p, t), and the entire system is immersed in the "vacuum" zero-point electromagnetic radiation. We show, in the first part of the paper, that the generalized Liouville equation is reduced to a simpler Liouville equation in the equilibrium limit where the small radiative corrections cancel each other approximately. This leads us to a simpler Liouville equation that will facilitate the calculations in the second part of the paper. Within this second part, we address ourselves to the following task: Since the Schrödinger equation depends on hbar , and the zero-point electromagnetic spectral distribution, given by ρ 0{(ω )} = hbar ω 3/2 π 2 c3, also depends on hbar , it is interesting to verify the possible dynamical connection between ρ 0( ω) and the Schrödinger equation. We shall prove that the Planck's constant, present in the momentum operator of the Schrödinger equation, is deeply related with the ubiquitous zero-point electromagnetic radiation with spectral distribution ρ 0( ω). For simplicity, we do not use the hypothesis of the existence of the L. de Broglie matter-waves. The implications of our study for the standard interpretation of the photoelectric effect are discussed by considering the main characteristics of the phenomenon. We also mention, briefly, the effects of the zero-point radiation in the tunneling phenomenon and the Compton's effect.

The vectorial photoelectric effect under solar irradiance and its application to sun sensing

International Nuclear Information System (INIS)

Hechenblaikner, Gerald; Ziegler, Tobias

2014-01-01

Sun sensors are an integral part of the attitude and orbit control system onboard almost any spacecraft. While the majority of standard analogue sun sensors is based on photo-detectors which produce photo-currents proportional to the cosine of the incidence angle (cosine detectors), we propose an alternative scheme where the vectorial photoelectric effect is exploited to achieve a higher sensitivity of the sensed photo-current to the incidence angle. The vectorial photo-effect is investigated in detail for metal cathode detectors in a space environment. Besides long operational lifetimes without significant degradation, metal cathode detectors are insensitive to earth albedo, which may significantly reduce the errors affecting attitude measurements in low earth orbits. Sensitivity curves are calculated and trade-offs performed with the aim of optimizing the sensitivity whilst also providing currents sufficient for detection. Simple applications and detector configurations are also discussed and compared to the existing designs. (paper)

Synthesis of GeSe2 Nanobelts Using Thermal Evaporation and Their Photoelectrical Properties

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Lijie Zhang

2014-01-01

Full Text Available GeSe2 nanobelts were synthesized via a simple thermal-evaporation process by using gold particles as catalyst and GeSe2 flakes as starting materials. The morphology, crystal structure, and composition were characterized with scanning electron microscopy (SEM, high-resolution transmission electron microscopy (TEM, X-ray diffraction spectroscopy (XRD, X-ray photoelectron spectroscopy (XPS, and energy-dispersive X-ray spectroscopy (EDS. SEM micrographs show that most of GeSe2 nanobelts have distinct segmented structures (wide belt, zigzag belt, and narrow belt. A possible mechanism was proposed for the growth of segmented nanobelts. It is possible that the growth of the segmented nanobelts is dominated by both vapor-liquid-solid and vapor-solid mechanisms. Devices made of single GeSe2 nanobelt have been fabricated and their photoelectrical property has been investigated. Results indicate that these nanobelt devices are potential building blocks for optoelectronic applications.

Deconvolving the temporal response of photoelectric x-ray detectors for the diagnosis of pulsed radiations

International Nuclear Information System (INIS)

Zou, Shiyang; Song, Peng; Pei, Wenbing; Guo, Liang

2013-01-01

Based on the conjugate gradient method, a simple algorithm is presented for deconvolving the temporal response of photoelectric x-ray detectors (XRDs) to reconstruct the resolved time-dependent x-ray fluxes. With this algorithm, we have studied the impact of temporal response of XRD on the radiation diagnosis of hohlraum heated by a short intense laser pulse. It is found that the limiting temporal response of XRD not only postpones the rising edge and peak position of x-ray pulses but also smoothes the possible fluctuations of radiation fluxes. Without a proper consideration of the temporal response of XRD, the measured radiation flux can be largely misinterpreted for radiation pulses of a hohlraum heated by short or shaped laser pulses

The development of student worksheet assisted by interactive multimedia of photoelectric effect to build science process skills

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Payudi Payudi

2017-12-01

Full Text Available This research aims to produce student worksheet based on interactive multimedia on photoelectric effect to grow science process skills that are attractive, easy, useful, and study to improve students learning out comes. The development design used in this research by Sugiono which implemented in 8 stages, they are potential and problem, data collecting, product design, validation design, revision design, product trial, product, and trial usage. Trial usage of the product was conducted at SMA Negeri 2 Bandar Lampung in October 2016 to November 2016 and the research subject was twelve grade classes. The sampling technique of product trial subjects done by purpose sampling, it took two same classes. One class used as an experimental class and the other class as a control class. Trial product design used Matching-Only Pretest-Post test Control Group Design method. Data collecting technique used questionnaire and test (pretest and post test. The data were analyzed by using a descriptive quantitative method. The conclusions of the research are: (1 Student worksheet to build scientific process skills on photoelectric effect should include predicting and hypothesizing activities, planning the experiment, doing the practicum, interpreting the observation, and communicating. (2 Student worksheet of development result has an attractiveness level with the average score is 3.27 or 81.74% with “interesting” category, ease level with the average score is 3.25 or 81.32 with “simple”, and usefulness level with the average score is 3.21 or 80.13% of “useful” category. (3 Student worksheet of development result is effective to improve students learning outcomes in science process skills with N-gain average is 0.63 with the medium.

Further measurements of K shell photoelectric cross sections for some elements in the range 26<=Z<=41 at 74 keV. [74. 409 keV

Energy Technology Data Exchange (ETDEWEB)

Arora, S K; Allawadhi, K L; Sood, B S [Punjabi Univ., Patiala (India). Dept. of Physics

1978-12-01

K shell photoelectric cross sections in elements Fe, Ni, Cu, Zn, As, Se, Br, Sr, Zr and Nb have been measured at 74.409 keV. The targets were irradiated with x radiation and gamma radiation beams. In confirmation with the earlier results, the present results also show fairly good agreement with theory.

Photoelectric schlieren method used to study the properties of diesel engine injection systems

International Nuclear Information System (INIS)

Reznicek, R.

1987-01-01

The time dependence of the fuel flow rate issuing from the injector nozzle represents very important information concerning the properties of Diesel engine injection systems. By analysing the delivery rate, it is possible to judge a new design, and the modifications and adjustments of Diesel engine injection systems. A number of devices for measuring the delivery rate, frequently founded on mechanical principles, have also been constructed. Mechanical methods are laborious, require complicated measuring instruments, and the analysis of the results is quite tedious. For investigating the delivery rate, one can also use the intensity of the luminous flux of the light ray which is intersected, and consequently its intensity decreased, by the flow of the delivered fuel. The schlieren method can be used for this purpose, employing a thin beam of parallel light rays and a photoelectric sensor placed immediately beyond the cut-off slit. After adjustment and calibration, the variations of the original electric signal represent the time variation of the delivery rate by the nozzle

Photoelectric UBV-photometry of the In(YY) DR Tauri-type young star in 1982-1986

International Nuclear Information System (INIS)

Kolotilov, E.A.

1987-01-01

The results of photoelectric UBV-photometry carried out in 1982-1986 for DR TAU - the star which undergone nova-like brightness increase in 1965-1980 - are presented. The brightness variations of the star during the post-maximum period include several days lasting flares and much more rare deep minima. The averaged colour-brightness relations are as follows: the higher brightness, the bluer B - V colour and the redder U - B colour. However the fast variations on a time scale of days do not always follow this relation. The observed pattern of variability of DR Tau is in agreement with the model of young stars activity (Grinin, 1980) proposing the appearance of hot spots in stellar atmosphere due to accretion of gas. Some arguments for the binarity of DR Tau are presented

Experimental investigation on photoelectric properties of ZAO thin film deposited on flexible substrate by magnetron sputtering

Science.gov (United States)

Hao, Ming; Liu, Kun; Liu, Xinghua; Wang, Dongyang; Ba, Dechun; Xie, Yuanhua; Du, Guangyu; Ba, Yaoshuai

2016-12-01

Transparent conductive ZAO (Zinc Aluminum Oxide) films on flexible substrates have a great potential for low-cost mass-production solar cells. ZAO thin films were achieved on flexible PET (polyethylene terephthalate) substrates by RF magnetron sputtering technology. The surface morphology and element content, the transmittance and the sheet resistance of the films were measured to determine the optical process parameters. The results show that the ZAO thin film shows the best parameters in terms of photoelectric performance including sputtering power, working pressure, sputtering time, substrate temperature (100 W, 1.5 Pa, 60 min, 125 °C). The sheet resistance of 510 Ω and transmittance in visible region of 92% were obtained after characterization. Surface morphology was uniform and compact with a good crystal grain.

Photoelectric effect in the relativistic domain revealed by the time-reversed process for highly charged uranium ions

International Nuclear Information System (INIS)

Stoehlker, T.; Mokler, P.H.; Kozhuharov, C.; Warczak, A.

1996-10-01

The photoelectric effect in the near relativistic energy regime of 80 to 350 keV is studied by the time-reversed process in ion-atom collisions, i.e. by the radiative capture of a quasi-free target electron. We review shell and subshell differential photon-angular distribution studies of radiative capture into highly-charged uranium ions. The experimental data are compared with exact relativistic calculations and give detailed insight into both the atomic structure of high-Z few-electron ions and into the fundamental electron-photon interaction process involved. In particular it is shown that the angular-differential measurements provide a unique method to study the magnetic interaction in relativistic electron-photon encoun- (orig.)

Photoelectric properties of thin films from the CdS-Ag2 S system

International Nuclear Information System (INIS)

Ristova-Lipanovikj, Mimoza

1996-01-01

Three different methods for preparation of thin films of CdS-Ag 2 S system are presented. Those methods are modified from the already existing methods of chemical deposition, and the method of spray pyrolysis, both widely utilized for preparation of wide range of binary, ternary and quaternary semiconductor thin films. The atomic absorption method was applied for quantitative analysis of the samples. The crystal structure of the thin films was studied by X-ray diffraction, while their morphology and the texture was analyzed from the microphotographs, taken on the samples by an optical microscope, in transmitted light. An extensive research was undertaken, to improve the crystallinity of the samples, by performing a post preparation thermal treatment. Photoelectric as well as some other physical properties were studied. VIS and NIR transmission spectra were recorded. The optical band gaps for various thin films containing different portions of Ag and Cd in the system, were evaluated. Spectral dependence of the photoconductivity was recorded. The optical band gaps were determined from the positions of the corresponding maxima of the photoconductivity. From the curves of the time relaxation of the photoconductivity, the carrier life times were calculates. Measurements of the thermal dependence of the resistivity on various samples were performed. Based on the extensive experimental research, the most convenient composition for PV application was selected. For the sake of comparison, two different types of PV cells were manufactured, Sn O 2 :F/CdS:Ag-Sn x S, and Sn O 2 :F/CdS-Sn x S, in order to study the influence of the silver content in the CdS. The plots of I-V and C-V characteristics are presented, and the parameters of the solar cells, were determined and taken in a relation with the content of the silver on the CdS. Finally, some directions of a possible future experimental and theoretical research in this field are given, based on the conclusions made. (author)

Electrical, optical and photoelectric properties of cadmium sulfide monocrystals doped by indium and irradiated by electrons

CERN Document Server

Davidyuk, G E; Manzhara, V S

2002-01-01

One studied effect of irradiation by E = 1.2 MeV energy and PHI = 2 x 10 sup 1 sup 7 cm sup - sup 2 dose fast electrons on electrical, optical and photoelectrical CdS single-crystals doped by In. On the basis of analysis of the experimental results one makes conclusions about decomposition and, in this case, indium atoms occurring in cation sublattice nodes are knocked out by cadmium atoms. In CdS:In irradiated specimens one detected new centres of slow recombination with occurrence of maximums of photoconductivity optical suppression within lambda sub M sub sub 1 = 0.75 mu m and lambda sub M sub sub 2 = 1.03 mu m range. It is assumed that complexes containing cadmium vacancies and indium atoms are responsible for recombination new centres

First measurements of electron-beam transit times and micropulse elongation in a photoelectric injector at the High-Brightness Accelerator FEL (HIBAF)

Energy Technology Data Exchange (ETDEWEB)

Lumpkin, A.H.; Carlsten, B.E.; Feldman, R.B.

1990-01-01

Key aspects of the dynamics of a photoelectric injector (PEI) on the Los Alamos High-Brightness Accelerator FEL (HIBAF) facility have been investigated using a synchroscan streak camera. By phase-locking the streak camera sweep to the reference 108.3 MHz rf signal, the variations of micropulse temporal elongations (30 to 80% over the drive-laser pulse length) and of transit times (25 ps for a 16{degree}-phase change) were observed for the first time. These results were in good agreement with PARMELA simulations. 2 refs., 8 figs.

Photoelectric atomic absorption cross sections for elements Z = 6 to 54 in the medium energy X-ray range (5 to 25 keV). Pt. 1

International Nuclear Information System (INIS)

Hildebrandt, G.; Stephenson, J.D.; Wagenfeld, H.

1975-01-01

Photoelectric atomic absorption cross sections have been calculated by means of hydrogen-like eigenfunctions for the atomic K, L, M and N sub-shells of the elements Z = 6 to 54, using revised screening constants and an extension of the theory. The absorption cross sections have been further separated into dipole and quadrupole components so that the numerical data can also be applied to the Borrmann effect. (orig.) [de

Formation Process of Eosin Y-Adsorbing ZnO Particles by Electroless Deposition and Their Photoelectric Conversion Properties.

Science.gov (United States)

Nagaya, Satoshi; Nishikiori, Hiromasa; Mizusaki, Hideaki; Wagata, Hajime; Teshima, Katsuya

2015-06-03

The thin films consisting of crystalline ZnO particles were prepared on fluorine-doped tin oxide electrodes by electroless deposition. The particles were deposited from an aqueous solution containing zinc nitrate, dimethyamine-borane, and eosin Y at 328 K. As the Pd particles were adsorbed on the substrate, not only the eosin Y monomer but also the dimer and debrominated species were rapidly adsorbed on the spherical ZnO particles, which were aggregated and formed secondary particles. On the other hand, in the absence of the Pd particles, the monomer was adsorbed on the flake-shaped ZnO particles, which vertically grew on the substrate surface and had a high crystallinity. The photoelectric conversion efficiency was higher for the ZnO electrodes containing a higher amount of the monomer during light irradiation.

Asymmetric photoelectric property of transparent TiO2 nanotube films loaded with Au nanoparticles

International Nuclear Information System (INIS)

Wang, Hui; Liang, Wei; Liu, Yiming; Zhang, Wanggang; Zhou, Diaoyu; Wen, Jing

2016-01-01

Highlights: • Highly transparent films of TiO 2 nanotube arrays were directly fabricated on FTO glasses. • Semitransparent TNT-Au composite films were obtained and exhibited excellent photoelectrocatalytic ability. • Back-side of TNT-Au composite films was firstly irradiated and tested to compare with front-side of films. - Abstract: Semitransparent composite films of Au loaded TiO 2 nanotubes (TNT-Au) were prepared by sputtering Au nanoparticles on highly transparent TiO 2 nanotubes films, which were fabricated directly on FTO glasses by anodizing the Ti film sputtered on the FTO glasses. Compared with pure TNT films, the prepared TNT-Au films possessed excellent absorption ability and high photocurrent response and improved photocatalytic activity under visible-light irradiation. It could be concluded that Au nanoparticles played important roles in improving the photoelectrochemical performance of TNT-Au films. Moreover, in this work, both sides of TNT-Au films were researched and compared owing to theirs semitransparency. It was firstly found that the photoelectric activity of TNT-Au composite films with back-side illumination was obviously superior to front-side illumination.

Oxide properties of autoclaved zircaloy cladding tubes investigated by the photoelectric polarization method

International Nuclear Information System (INIS)

Nystrand, A.C.

2000-06-01

Corrosion of zirconium alloys is an important lifetime limiting factor for the nuclear reactor fuel. The corrosion resistance of a metal is highly dependent on the ability of the surface metal oxide to transport electrons and ions, which is related to the stoichiometry of the oxide and the oxide defect concentration. The Photoelectric Polarization Method (PEP) is a structure sensitive method which earlier has been investigated as a possible method to study the defect structure in zirconium oxides. The purpose of the following work is, by using more optimized experimental equipment, to verify if the PEP method is a suitable method to study the defect structure in zirconium oxides and to predict the corrosion resistance for different zirconium alloys. The conclusions from the experiments are as follows: - The modifications of the experimental setup by means of a new source of light (deuterium lamp) and a new oscilloscope with an amplifier gave distinct Vpep signals. - The photoresponse is negative for all types of cladding and under all kind of oxidation regimes and hence the oxide is a n-type semiconductor with deficiency of oxygen. - The method needs to be verified by testing semiconductors with a known defect concentration

The photoelectric effect and study of the diffraction of light: Two new experiments in UNILabs virtual and remote laboratories network

International Nuclear Information System (INIS)

Sánchez, Juan Pedro; Carreras, Carmen; Yuste, Manuel; Dormido, Sebastián; Sáenz, Jacobo; De la Torre, Luis; Rubén, Heradio

2015-01-01

This work describes two experiments: 'study of the diffraction of light: Fraunhofer approximation' and 'the photoelectric effect'. Both of them count with a virtual, simulated, version of the experiment as well as with a real one which can be operated remotely. The two previous virtual and remote labs (built using Easy Java(script) Simulations) are integrated in UNILabs, a network of online interactive laboratories based on the free Learning Management System Moodle. In this web environment, students can find not only the virtual and remote labs but also manuals with related theory, the user interface description for each application, and so on.

Influence of radiation on photo-electric characteristics of silicon photo cells with optical coverings

International Nuclear Information System (INIS)

Madatov, R.S.; Safarov, N.A.; Gasymova, V.G.; Abdurragimov, A.A.; Allahverdiev, A.M.

2003-01-01

In the given work results of measurements volt-ampere and spectral characteristics of silicon photo cells with optical coverings ZnS+Nd 2 O 3 irradiated accelerated electrons with energy 4.5 MeV are carried out. Elements have been made by diffusion of phosphorus in p-silicon with specific resistance 2 Ω·cm. Under condition of illumination from source AMI the photocurrent of short circuit made 40 mA/cm 2 , and a photo voltage of idling 0.52 V, efficiency made 15 %. To receive low reflection in wide area of spectral sensitivity and by that as much as possible to increase efficiency of elements with the help of two-layer coverings. The irradiation of samples was made on linear accelerator EL4-6 at room temperature. It is received, that with increase in a dose of an irradiation the Photocurrent and photo voltage decreases, and speed reduction of a photo-current is stronger, than photo voltage. The critical integrated stream for these elements makes 4·10 12 el/cm 2 . In all researched samples radiating reduction of a voltage of idling in an interval of 10 10 -10 14 el/cm 2 makes 8-10 %. The analysis of spectral characteristics of the irradiated samples show, that reduction of a photocurrent in long-wave areas of a spectrum is connected by creation of radiating defects in a base part of an element. The increase in a critical stream in silicon solar elements with optical a covering in comparison with elements without a covering is connected with low concentration of defects in the base, created with electron. Thus, on the basis of complex research of influence on radiating stability silicon solar elements us it is established, that two-layer coverings not only increases efficiency of photo cells, but also considerably raise value of an integrated stream electrons, that is equivalent to increase in service life of the elements working in conditions of radiation

Photoelectric characteristics of lead phthalocyanine/titanium oxide structures

CERN Document Server

Ray, A K; Hodgson, S N B

2003-01-01

A study has been carried out into the conduction, charge transfer/electron injection and photovoltaic conversion properties of TiO sub 2 -lead phthalocyanine (PbPc) heterojunctions. The results indicate that although the heterojunction area, and hence overall conversion efficiency, was low for the planar device structures used in the investigation, electron injection and effective charge separation across the dye-TiO sub 2 interface was achieved, with open circuit voltages in the region of 0.3 V. The conversion efficiency was found to be a function of the thickness of the phthalocyanine layer, increasing by a factor of more than 30 times as the thickness of the dye layer was reduced from 500 to 100 nm. The results suggest that under appropriate deposition conditions, to ensure effective coating of the inorganic phase, such phthalocyanine dyes may offer potential for use in dye sensitized photovoltaic cells.

Studies on structural, optical, and photoelectric properties of CdS{sub 1-x}Se{sub x} films fabricated by selenization of chemical bath deposited CdS films

Energy Technology Data Exchange (ETDEWEB)

Lu, Tianyu; Gu, Han; Ge, Zhenhua; Zhang, Lei; Wang, Zhicheng; Fang, Yong; Han, Zhida; Qian, Bin; Jiang, Xuefan [Department of Physics, Changshu Institute of Technology, Changshu (China); Wu, Wangping [School of Mechanical Engineering, Changzhou University, Changzhou (China)

2017-02-15

In this paper, high-photosensitive CdS{sub 1-x}Se{sub x} films are synthesized by a two-step technique, which includes the chemical bath deposition of CdS films and a following selenization process. The structural, optical, and photoelectric properties of the CdS{sub 1-x}Se{sub x} films were investigated. With the substitution of selenium for sulfur atoms, grain sizes of the as-prepared CdS{sub 1-x}Se{sub x} films are effectively enlarged and reach the scales of the films thickness when the selenization temperature exceeds 450 C. With increasing the selenization temperature from 350 to 550 C, the band gaps of CdS{sub 1-x}Se{sub x} films gradually decrease from 2.37 to 1.82 eV. Under the co-action of the grain-size enlargement and band-gap decrease, the CdS{sub 1-x}Se{sub x} films fabricated at 450 C show very pronounced photosensitivity. Noteworthy, the ratio of photo to dark conductivity of the CdS{sub 1-x}Se{sub x} film selenized at 450 C reaches 1.1 x 10{sup 5}, suggesting a promising application potential in the photoelectric devices. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

The sandwich InGaAs/GaAs quantum dot structure for IR photoelectric detectors

International Nuclear Information System (INIS)

Moldavskaya, L. D.; Vostokov, N. V.; Gaponova, D. M.; Danil'tsev, V. M.; Drozdov, M. N.; Drozdov, Yu. N.; Shashkin, V. I.

2008-01-01

A new possibility for growing InAs/GaAs quantum dot heterostructures for infrared photoelectric detectors by metal-organic vapor-phase epitaxy is discussed. The specific features of the technological process are the prolonged time of growth of quantum dots and the alternation of the low-and high-temperature modes of overgrowing the quantum dots with GaAs barrier layers. During overgrowth, large-sized quantum dots are partially dissolved, and the secondary InGaAs quantum well is formed of the material of the dissolved large islands. In this case, a sandwich structure is formed. In this structure, quantum dots are arranged between two thin layers with an increased content of indium, namely, between the wetting InAs layer and the secondary InGaAs layer. The height of the quantum dots depends on the thickness of the GaAs layer grown at a comparatively low temperature. The structures exhibit intraband photoconductivity at a wavelength around 4.5 μm at temperatures up to 200 K. At 90 K, the photosensitivity is 0.5 A/W, and the detectivity is 3 x 10 9 cm Hz 1/2 W -1

Optimal design of a high accuracy photoelectric auto-collimator based on position sensitive detector

Science.gov (United States)

Yan, Pei-pei; Yang, Yong-qing; She, Wen-ji; Liu, Kai; Jiang, Kai; Duan, Jing; Shan, Qiusha

2018-02-01

A kind of high accuracy Photo-electric auto-collimator based on PSD was designed. The integral structure composed of light source, optical lens group, Position Sensitive Detector (PSD) sensor, and its hardware and software processing system constituted. Telephoto objective optical type is chosen during the designing process, which effectively reduces the length, weight and volume of the optical system, as well as develops simulation-based design and analysis of the auto-collimator optical system. The technical indicators of auto-collimator presented by this paper are: measuring resolution less than 0.05″; a field of view is 2ω=0.4° × 0.4° measuring range is +/-5' error of whole range measurement is less than 0.2″. Measuring distance is 10m, which are applicable to minor-angle precise measuring environment. Aberration analysis indicates that the MTF close to the diffraction limit, the spot in the spot diagram is much smaller than the Airy disk. The total length of the telephoto lens is only 450mm by the design of the optical machine structure optimization. The autocollimator's dimension get compact obviously under the condition of the image quality is guaranteed.

STAR FORMATION IN DISK GALAXIES. II. THE EFFECT OF STAR FORMATION AND PHOTOELECTRIC HEATING ON THE FORMATION AND EVOLUTION OF GIANT MOLECULAR CLOUDS

International Nuclear Information System (INIS)

Tasker, Elizabeth J.

2011-01-01

We investigate the effect of star formation and diffuse photoelectric heating on the properties of giant molecular clouds (GMCs) formed in high-resolution (∼ H,c >100 cm -3 are identified as GMCs. Between 1000 and 1500 clouds are created in the simulations with masses M>10 5 M sun and 180-240 with masses M>10 6 M sun in agreement with estimates of the Milky Way's population. We find that the effect of photoelectric heating is to suppress the fragmentation of the interstellar medium, resulting in a filamentary structure in the warm gas surrounding clouds. This environment suppresses the formation of a retrograde rotating cloud population, with 88% of the clouds rotating prograde with respect to the galaxy after 300 Myr. The diffuse heating also reduces the initial star formation rate (SFR), slowing the conversation of gas into stars. We therefore conclude that the interstellar environment plays an important role in the GMC evolution. Our clouds live between 0 and 20 Myr with a high infant mortality (t' < 3 Myr) due to cloud mergers and star formation. Other properties, including distributions of mass, size, and surface density, agree well with observations. Collisions between our clouds are common, occurring at a rate of ∼ 1/4 of the orbital period. It is not clear whether such collisions trigger or suppress star formation at our current resolution. Our SFR is a factor of 10 higher than observations in local galaxies. This is likely due to the absence of localized feedback in our models.

Characteristics of withstanding radiation damage of InP crystals and devices

International Nuclear Information System (INIS)

Yamaguchi, Masafumi; Ando, Koshi

1988-01-01

Recently, the authors discovered that the characteristics of with standing radiation damage of InP crystals and devices (solar cells) are superior to those of Si and GaAs crystals and devices. Also the restoration phenomena at room temperature of radiation deterioration and the accelerated anneal phenomena by light irradiation and the injection of other minority, carriers in InP system devices were found. Such excellent characteristics suggested that InP devices are promising for the use in space. In this paper, taking an example of solar cells, the radiation resistance characteristics and their mechanism of InP crystals and devices are reported, based on the results of analysis by deep level transient spectroscopy and others. In InP solar cells, the high efficiency of photoelectric conversion was maintained even in the high dose irradiation of 1 MeV electron beam. As the carrier concentration in InP crystals is higher, they are stronger against radiation. With the increase of carrier concentration, the rate of anneal of radiation deterioration at room temperature increased. The accelerated anneal effect by minority carrier injection was remarkable in n + -p junction cells. The excellent characteristics of InP crystals are due to the formation of Frenkel defects of P and their instability. (K.I.)

Effect of ZrO2 film thickness on the photoelectric properties of mixed-cation perovskite solar cells

Science.gov (United States)

Li, Yanyan; Zhao, Li; Wei, Shoubin; Xiao, Meng; Dong, Binghai; Wan, Li; Wang, Shimin

2018-05-01

In this work, perovskite solar cells (PSCs) were fabricated in the ambient air, with a scaffold layer composed of TiO2/ZrO2 double layer as the mesoscopic layer and carbon as the counter electrode. The effect of ZrO2 thin film thickness on the photovoltaic performances of PSCs was also studied in detail. Results showed that the photoelectric properties of as-prepared PSCs largely depend on the thin film thickness due to a series of factors, including surface roughness, charge transport resistance, and electron-hole recombination rate. The power conversion efficiency of PSCs increased from 8.37% to 11.33% by varying the thin film thickness from 75 nm to 305 nm, and the optimal power conversion efficiency was realized up to the 11.33% with a thin film thickness of 167 nm. This research demonstrates a promising route for the high-efficiency and low-cost photovoltaic technology.

Synchronous photoelectrical observations of flare stars in the visible and near infrared ranges

International Nuclear Information System (INIS)

Bruevich, V.V.; Kilyachkov, N.N.; Shevchenko, V.S.; Burnashov, V.I.; Grinin, V.P.; Koryshev, V.V.; Shakhovskaya, N.I.

1980-01-01

The results of synchronous photoelectrical observations of the AD Leo and EV Lac flare stars made in 1975 in the Crimea in B-filter and in the near infrared region (i-band, lambdasub(ef) approximately 0.85 μm) and the observations of the UV Cet and EV Lac stars made in 1976 in the Astronomical Institute Uzbek SSR in three passbands: U, isub(TiO)(lambdasub(ef)=0.71 μ) and isub(C)(lambdasub(ef)=0.80μm) are given. Practically all strong flares in the visible spectral range were followed by the IR-flares. In about 70% of the cases the predicted infrared negative preflares were observed. The amplitudes (in erg/s) of the negative flares are comparable with the amplitude of the optical flares. The analysis of the observed data shows that: a) the amplitudes and the energies of the positive IR flares are in average the larger the stronger is the optical flare; b) the amplitudes of the negative IR preflares are on the contrary the smaller the stronger is the optical flare; c) there are infrared flares the main energy out of which takes place in the infrared range of wavelengths; d) The U-i color shows a positive correlation with the amplitude of the flare in U: the stronger is the flare the bluer is its radiation

Photoelectric Properties of Silicon Nanocrystals/P3HT Bulk-Heterojunction Ordered in Titanium Dioxide Nanotube Arrays

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Švrček Vladimir

2009-01-01

Full Text Available Abstract A silicon nanocrystals (Si-ncs conjugated-polymer-based bulk-heterojunction represents a promising approach for low-cost hybrid solar cells. In this contribution, the bulk-heterojunction is based on Si-ncs prepared by electrochemical etching and poly(3-hexylthiophene (P3HT polymer. Photoelectric properties in parallel and vertical device-like configuration were investigated. Electronic interaction between the polymer and surfactant-free Si-ncs is achieved. Temperature-dependent photoluminescence and transport properties were studied and the ratio between the photo- and dark-conductivity of 1.7 was achieved at ambient conditions. Furthermore the porous titanium dioxide (TiO2 nanotubes’ template was used for vertical order of photosensitive Si-ncs/P3HT-based blend. The anodization of titanium foil in ethylene glycol-based electrolyte containing fluoride ions and subsequent thermal annealing were used to prepare anatase TiO2nanotube arrays. The arrays with nanotube inner diameter of 90 and 50 nm were used for vertical ordering of the Si-ncs/P3HT bulk-heterojunction.

Subdivision Error Analysis and Compensation for Photoelectric Angle Encoder in a Telescope Control System

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Yanrui Su

2015-01-01

Full Text Available As the position sensor, photoelectric angle encoder affects the accuracy and stability of telescope control system (TCS. A TCS-based subdivision error compensation method for encoder is proposed. Six types of subdivision error sources are extracted through mathematical expressions of subdivision signals first. Then the period length relationships between subdivision signals and subdivision errors are deduced. And the error compensation algorithm only utilizing the shaft position of TCS is put forward, along with two control models; Model I is that the algorithm applies only to the speed loop of TCS and Model II is applied to both speed loop and position loop. Combined with actual project, elevation jittering phenomenon of the telescope is discussed to decide the necessity of DC-type subdivision error compensation. Low-speed elevation performance before and after error compensation is compared to help decide that Model II is preferred. In contrast to original performance, the maximum position error of the elevation with DC subdivision error compensation is reduced by approximately 47.9% from 1.42″ to 0.74″. The elevation gets a huge decrease in jitters. This method can compensate the encoder subdivision errors effectively and improve the stability of TCS.

Asymmetric photoelectric property of transparent TiO{sub 2} nanotube films loaded with Au nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Wang, Hui [College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024 (China); College of Applied Science, Taiyuan University of Science and Technology, Taiyuan, Shanxi 030024 (China); Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, Shanxi 030024 (China); Liang, Wei, E-mail: 986903124@qq.com [College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024 (China); Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, Shanxi 030024 (China); Liu, Yiming; Zhang, Wanggang; Zhou, Diaoyu; Wen, Jing [College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024 (China); Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, Shanxi 030024 (China)

2016-11-15

Highlights: • Highly transparent films of TiO{sub 2} nanotube arrays were directly fabricated on FTO glasses. • Semitransparent TNT-Au composite films were obtained and exhibited excellent photoelectrocatalytic ability. • Back-side of TNT-Au composite films was firstly irradiated and tested to compare with front-side of films. - Abstract: Semitransparent composite films of Au loaded TiO{sub 2} nanotubes (TNT-Au) were prepared by sputtering Au nanoparticles on highly transparent TiO{sub 2} nanotubes films, which were fabricated directly on FTO glasses by anodizing the Ti film sputtered on the FTO glasses. Compared with pure TNT films, the prepared TNT-Au films possessed excellent absorption ability and high photocurrent response and improved photocatalytic activity under visible-light irradiation. It could be concluded that Au nanoparticles played important roles in improving the photoelectrochemical performance of TNT-Au films. Moreover, in this work, both sides of TNT-Au films were researched and compared owing to theirs semitransparency. It was firstly found that the photoelectric activity of TNT-Au composite films with back-side illumination was obviously superior to front-side illumination.

Comparison and selection of off-grid PV systems

Science.gov (United States)

Izmailov, Andrey Yu.; Lobachevsky, Yakov P.; Shepovalova, Olga V.

2018-05-01

This work deals with comparison, evaluation and selection of PV systems of the same type based on their technical parameters either indicated in their technical specifications or calculated ones. Stand-alone and grid backed up photoelectric systems have been considered. General requirements for photoelectric system selection and evaluation have been presented that ensure system operability and required efficiency in operation conditions. Generic principles and definition of photoelectric systems characteristics have been considered. The described method is mainly targeted at PV engineering personnel and private customers purchasing PV systems. It can be also applied in the course of project contests, tenders, etc.

Spectral and spatial resolving of photoelectric property of femtosecond laser drilled holes of GaSb(1-x)Bi(x).

Science.gov (United States)

Pan, C B; Zha, F X; Song, Y X; Shao, J; Dai, Y; Chen, X R; Ye, J Y; Wang, S M

2015-07-15

Femtosecond laser drilled holes of GaSbBi were characterized by the joint measurements of photoconductivity (PC) spectroscopy and laser-beam-induced current (LBIC) mapping. The excitation light in PC was focused down to 60 μm presenting the spectral information of local electronic property of individual holes. A redshift of energy band edge of about 6-8 meV was observed by the PC measurement when the excitation light irradiated on the laser drilled holes. The spatial resolving of photoelectric property was achieved by the LBIC mapping which shows "pseudo-holes" with much larger dimensions than the geometric sizes of the holes. The reduced LBIC current with the pseudo-holes is associated with the redshift effect indicating that the electronic property of the rim areas of the holes is modified by the femtosecond laser drilling.

Effect of Core-Shell Ag@TiO2 Volume Ratio on Characteristics of TiO2-Based DSSCs

Directory of Open Access Journals (Sweden)

Ho Chang

2014-01-01

Full Text Available This paper aims to develop photoanode material required by dye-sensitized solar cells. The material prepared is in the form of Ag@TiO2 core-shell-type nanocomposites. This material is used to replace the titanium oxide powder commonly used in general DSSCs. The prepared Ag@TiO2 core-shell-type nanocomposites are mixed with Degussa P25 TiO2 in different proportions. Triton X-100 is added and polyethylene glycol (PEG at 20 wt% is used as a polymer additive. This study tests the particle size and material properties of Ag@TiO2 core-shell-type nanocomposites and measures the photoelectric conversion efficiency and IPCE of DSSCs. Experimental results show that the DSSC prepared by Ag@TiO2 core-shell-type nanocomposites can achieve a photoelectric conversion efficiency of 3.67%. When Ag@TiO2 core-shell-type nanocomposites are mixed with P25 nanoparticles in specific proportions, and when the thickness of the photoelectrode thin film is 28 μm, the photoelectric conversion efficiency can reach 6.06%, with a fill factor of 0.52, open-circuit voltage of 0.64V, and short-circuit density of 18.22 mAcm−2. Compared to the DSSC prepared by P25 TiO2 only, the photoelectric conversion efficiency can be raised by 38% under the proposed approach.

Light curve of the CX Cep eclipsing binary system and characteristics of a Wolf-Rayet star

International Nuclear Information System (INIS)

Lipunova, N.A.; Cherepashchuk, A.M.

1982-01-01

The photoelectric B, V, R observations of the eclipsing Wolf-Rayet binary CX Cep (WN 5 + 08V, V approximately equal to 12sup(m),1, p approximately equal to 2sup(d),127) have been carried out. The physical characteristics of the WN 5 star, the core radius r 0 =(4.5+-2.5) Rsub(S) (Rsub(S) is the Sun radius) and the brightness temperature of the core Tsub(b)>50 000 K, are determined from the analysis of the light curve lambdasub(eff) approximately equal to 6 000 A. These characteristics are close to those of the WN 5 star in the eclipsing Wolf-Rayet binary V 444 Cyg. The results of the interpretation of the light curves of two eclipsing Wolf-Rayet binaries (V 444 Cyg and CX Cep) confirm the conclusions of the modern theory of evolution of massive close binary systems [ru

Synthesis and photoelectrical performance of nanoscale PbS and Bi2S3 co-sensitized on Ti02 nanotube arrays

Institute of Scientific and Technical Information of China (English)

Fanggong Cai; Min Pan; Yong Feng; Guo Yan; Yong Zhang; Yong Zhao

2017-01-01

TiO2 films have been widely applied in photovoltaic conversion techniques.TiO2 nanotube arrays (TiO2 NAs) can be grown directly on the surface of metal Ti by the anodic oxidation method.Bi2S3 and PbS nanoparticles (NPs) were firstly co-sensitized on TiO2 NAs (denoted as PbS/Bi2S3(n)/TiO2 NAs) by a two-step process containing hydrothermal and sonication-assisted SILAR method.When the concentration of Bi3+ is 5 mmol/L,the best photoelectrical performance was obtained under simulated solar irradiation.The short-circuit photocurrent (Jsc) and photoconversion efficiency (η) of PbS/Bi2S3(5)/TiO2 NAs electrode were 4.70 mA/cm and 1.13 ％,respectively.

Decrease of oxygen vacancy by Zn-doped for improving solar-blind photoelectric performance in β-Ga2O3 thin films

Science.gov (United States)

Guo, Daoyou; Qin, Xinyuan; Lv, Ming; Shi, Haoze; Su, Yuanli; Yao, Guosheng; Wang, Shunli; Li, Chaorong; Li, Peigang; Tang, Weihua

2017-11-01

Highly (201) oriented Zn-doped β-Ga2O3 thin films with different dopant concentrations were grown on (0001) sapphire substrates by radio frequency magnetron sputtering. With the increase of Zn dopant concentration, the crystal lattice expands, the energy band gap shrinks, and the oxygen vacancy concentration decreases. Both the metal semiconductor metal (MSM) structure photodetectors based on the pure and Zn-doped β-Ga2O3 thin films exhibit solar blind UV photoelectric property. Compared to the pure β-Ga2O3 photodetector, the Zn-doped one exhibits a lower dark current, a higher photo/dark current ratio, a faster photoresponse speed, which can be attributed to the decreases of oxygen vacancy concentration.[Figure not available: see fulltext.

Design and practice of a novel experiment teaching system based on the optoelectric information chain

Science.gov (United States)

Luo, Yunhan; Chen, Zhe; Li, Yan; Di, Hongwei; Li, Zhen; Bai, Chunhe; Tang, Jieyuan; Zhang, Jun; Yi, Xiao

2017-08-01

The course of optoelectronic information science is a diverse science and technology with wide range of disciplines, intensive technology, and strong applicability. As a result, the practice teaching in undergraduate education occupies the strategic important position, which is a key link in the process of innovative talents cultivation of photoelectric information, plays a unique and irreplaceable role by any other teaching methods. In order to meet the requirements of national innovative talents of photoelectric information, the complete teaching reform strategy was put forward by combining with the higher education policy and development strategy of teaching and professional characteristics. The goal of the experimental teaching reform is to cultivate innovative talents and to construct the photoelectric information industry chain system of experimental teaching platform and cultivating creative personnel. The key clue is the photoelectric information surrounding photoelectric information, like "generation - modulation - transformation - detection - procession" which will be realized by resource integration and complementary among cross disciplines, and focusing on scientific research support for the teaching and the combination of professional knowledge and practical application. This teaching reform scheme presented in the paper will provide very good demonstration effect in the curriculum reform of other photoelectric information related courses.

Transport charge of gallium arsenide films synthesized on polycrystalline silicon by ion ablation

International Nuclear Information System (INIS)

Kabyshev, A V; Konusov, F V; Remnev, G E; Pavlov, S K

2014-01-01

Electrophysical and photoelectric properties of thin GaAs films deposited on polysilicon by pulse ion ablation using high-power ion beams have been investigated. The predominant charge carriers transfer mechanism in films and the type of dark and photoconductivity have been established. A vacuum annealing effect (10 −2 Pa, 300-1000 K) on energetic and kinetic characteristics of dark and photoconductivity, the transfer mechanism and the type of charge carriers have been determined. The most probable causes of changes in the film electric and photoelectric characteristics have been discussed

Enhancement of the photo-electric effect with pharmacological agents in synchrotron radiation based anti-cancer radiotherapy: a methodological study

International Nuclear Information System (INIS)

Corde, Stephanie

2002-01-01

Anti-cancer therapy rests on three main principles: 1) anatomic confinement of irradiation; 2) temporal fractioning of treatment; 3) treatment of tissues that are more sensitive to radiation than surrounding healthy tissue. Under those principles hides the goal of radiotherapy: to deposit more of the X-ray energy in the tumor while preserving the surrounding healthy tissues. This goal is hard to reach since one of the causes of the failures in radiotherapy is the continuing evolution of the tumor. Could synchrotron radiation be more effective as an X-ray source for radiotherapy? The variation of the radiation-matter interaction cross-sections as a function of X-ray energy and atomic number of the medium show that certain energies and certain elements are more suitable to obtain the largest number of interactions and the largest amount of deposited energy. Synchrotron radiation allows to select precisely those energies because of its high spectral intensity. Its spectral characteristics (energy of the photons between 10 and 100 keV) allow to trigger the photoelectric effect with a maximum of probability on heavy elements introduced close to cancerous cells. It has been shown that: 1) synchrotron radiation based tomodensitometry is a quantitative imaging technique, potentially powerful for radiotherapy since it insures in-vivo the measurement of intra-tumoral concentration of contrast agent (I or Gd); 2) in the presence of iodinated contrast agent the lethal effect of X-rays on cell survival is increased and the gain in radio sensitivity depends on X-ray energy; 3) at the cellular scale the lethality of irradiation can be optimised again by transporting heavy atoms (I, Pt) inside the DNA, which is the biological target of the irradiation. This reinforcement of the killing efficiency of low energy X-rays using a physical mechanism aimed at a pharmacological agent is an original concept in anti-cancer radiotherapy. (author) [fr

Variable interstellar radiation fields in simulated dwarf galaxies: supernovae versus photoelectric heating

Science.gov (United States)

Hu, Chia-Yu; Naab, Thorsten; Glover, Simon C. O.; Walch, Stefanie; Clark, Paul C.

2017-10-01

We present high-resolution hydrodynamical simulations of isolated dwarf galaxies including self-gravity, non-equilibrium cooling and chemistry, interstellar radiation fields (ISRF) and shielding, star formation, and stellar feedback. This includes spatially and temporally varying photoelectric (PE) heating, photoionization, resolved supernova (SN) blast waves and metal enrichment. A new flexible method to sample the stellar initial mass function allows us to follow the contribution to the ISRF, the metal output and the SN delay times of individual massive stars. We find that SNe play the dominant role in regulating the global star formation rate, shaping the multiphase interstellar medium (ISM) and driving galactic outflows. Outflow rates (with mass-loading factors of a few) and hot gas fractions of the ISM increase with the number of SNe exploding in low-density environments where radiative energy losses are low. While PE heating alone can suppress star formation as efficiently as SNe alone can do, it is unable to drive outflows and reproduce the multiphase ISM that emerges naturally whenever SNe are included. We discuss the potential origins for the discrepancy between our results and another recent study that claimed that PE heating dominates over SNe. In the absence of SNe and photoionization (mechanisms to disperse dense clouds), the impact of PE heating is highly overestimated owing to the (unrealistic) proximity of dense gas to the radiation sources. This leads to a substantial boost of the infrared continuum emission from the UV-irradiated dust and a far-infrared line-to-continuum ratio too low compared to observations.

The Effect of Metal-Semiconductor Contact on the Transient Photovoltaic Characteristic of HgCdTe PV Detector

Directory of Open Access Journals (Sweden)

Haoyang Cui

2013-01-01

Full Text Available The transient photovoltaic (PV characteristic of HgCdTe PV array is studied using an ultrafast laser. The photoresponse shows an apparent negative valley first, then it evolves into a positive peak. By employing a combined theoretical model of pn junction and Schottky potential, this photo-response polarity changing curves can be interpreted well. An obvious decreasing of ratio of negative valley to positive peak can be realized by limiting the illumination area of the array electrode. This shows that the photoelectric effect of Schottky barrier at metal-semiconductor (M/S interface is suppressed, which will verify the correctness of the model. The characteristic parameters of transient photo-response induced from p-n junction and Schottky potential are extracted by fitting the response curve utilizing this model. It shows that the negative PV response induced by the Schottky barrier decreases the positive photovoltage generated by the pn junction.

ANALYSIS OF THE ELECTROPHYSICAL AND PHOTOELECTRIC PROPERTIES OF NANOCOMPOSITE POLYMERS BY THE MODIFIED KELVIN PROBE

Directory of Open Access Journals (Sweden)

K. U. Pantsialeyeu

2017-01-01

Full Text Available At present for analysis of the homogeneity of materials properties are becoming widely used various modifications of a scanning Kelvin probe. These methods allow mapping the spatial distribution of the electrostatic potential. Analysis of the electropotential profile is not sufficient to describe any specific physical parameters of the polymer nanocomposites. Therefore, we use an external energy impact, such as light. Purpose of paper is the modification of the Kelvin scanning probe and the conduct of experimental studies of the spatial distribution and response of the electrostatic potential of the actual polymer nanocomposites to the optical probing.Carried out the investigations on experimental Low density polyethylene composites. Carbon nanomaterials and nanoparticles of silicon dioxide or aluminum as fillers are used. As a result, maps of the spatial distribution of the electrostatic potential relative values and the surface photovoltage. Statistical analysis of the electrophysical and photoelectric properties homogeneity, depending on the component composition of the composites carried out. In addition, with reference to matrix polymers, the Kelvin scanning probe, in combination with the optical probing, made it possible to detect a piezoelectric effect. The latter, can used as a basis for the development of new methods for studying the mechanical properties of matrix polymers.

Paradoxes of photoconductive target and optical control of secondary ion yield

International Nuclear Information System (INIS)

Rokakh, A. G.; Matasov, M. D.

2010-01-01

This study of the photoconductivity of semiconductors, in particular, cadmium chalcogenides as materials for targets of vacuum image converters followed the path of overcoming paradoxes. The concepts developed by the classics of photoelectricity also help to understand the paradoxes of the new secondary-ion photoelectric effect, especially, its spectral characteristic. The optical channel of secondary ion yield control via a photoconductive target opens the way to a new branch of nanotechnology, i.e., optoionics.

CdTe polycrystalline films on Ni foil substrates by screen printing and their photoelectric performance

International Nuclear Information System (INIS)

Yao, Huizhen; Ma, Jinwen; Mu, Yannan; Su, Shi; Lv, Pin; Zhang, Xiaoling; Zhou, Liying; Li, Xue; Liu, Li; Fu, Wuyou; Yang, Haibin

2015-01-01

Highlights: • The sintered CdTe polycrystalline films by a simple screen printing. • The flexible Ni foil was chose as substrates to reduce the weight of the electrode. • The compact CdTe film was obtained at 550 °C sintering temperature. • The photoelectric activity of the CdTe polycrystalline films was excellent. - Abstract: CdTe polycrystalline films were prepared on flexible Ni foil substrates by sequential screen printing and sintering in a nitrogen atmosphere for the first time. The effect of temperature on the quality of the screen-printed film was investigated in our work. The high-quality CdTe films were obtained after sintering at 550 °C for 2 h. The properties of the sintered CdTe films were characterized by scanning electron microscopy, X-ray diffraction pattern and UV–visible spectroscopy. The high-quality CdTe films have the photocurrent was 2.04 mA/cm 2 , which is higher than that of samples prepared at other temperatures. Furthermore, CdCl 2 treatment reduced the band gap of the CdTe film due to the larger grain size. The photocurrent of photoelectrode based on high crystalline CdTe polycrystalline films after CdCl 2 treatment improved to 2.97 mA/cm 2 , indicating a potential application in photovoltaic devices

Bistable impurity centers in silicon. Temperature dependent characteristics of electro- and thermophysical parameters

Energy Technology Data Exchange (ETDEWEB)

Musaeva, L F; Igamberdiev, Kh T; Mamadalimov, A T; Khabibullaev, P K [AS RU, Heat Physics Department, Tashkent (Uzbekistan)

2003-09-01

On the basis of experimental data covering temperature dependencies of photoelectric and thermodynamic properties of silicon containing defects the possible physical mechanisms of defect center transformation in the silicon lattice and of phase transitions are discussed. (author)

Bistable impurity centers in silicon. Temperature dependent characteristics of electro- and thermophysical parameters

International Nuclear Information System (INIS)

Musaeva, L.F.; Igamberdiev, Kh.T.; Mamadalimov, A.T.; Khabibullaev, P.K.

2003-01-01

On the basis of experimental data covering temperature dependencies of photoelectric and thermodynamic properties of silicon containing defects the possible physical mechanisms of defect center transformation in the silicon lattice and of phase transitions are discussed. (author)

Graphene quantum dot (GQD)-induced photovoltaic and photoelectric memory elements in a pentacene/GQD field effect transistor as a probe of functional interface

Science.gov (United States)

Kim, Youngjun; Cho, Seongeun; Kim, Hyeran; Seo, Soonjoo; Lee, Hyun Uk; Lee, Jouhahn; Ko, Hyungduk; Chang, Mincheol; Park, Byoungnam

2017-09-01

Electric field-induced charge trapping and exciton dissociation were demonstrated at a penatcene/grapheme quantum dot (GQD) interface using a bottom contact bi-layer field effect transistor (FET) as an electrical nano-probe. Large threshold voltage shift in a pentacene/GQD FET in the dark arises from field-induced carrier trapping in the GQD layer or GQD-induced trap states at the pentacene/GQD interface. As the gate electric field increases, hysteresis characterized by the threshold voltage shift depending on the direction of the gate voltage scan becomes stronger due to carrier trapping associated with the presence of a GQD layer. Upon illumination, exciton dissociation and gate electric field-induced charge trapping simultaneously contribute to increase the threshold voltage window, which can potentially be exploited for photoelectric memory and/or photovoltaic devices through interface engineering.

ZnO/Cu/ZnO multilayer films: Structure optimization and investigation on photoelectric properties

International Nuclear Information System (INIS)

Liu Xiaoyu; Li Yingai; Liu Shi; Wu Honglin; Cui Haining

2012-01-01

A series of ZnO/Cu/ZnO multilayer films has been fabricated from zinc and copper metallic targets by simultaneous RF and DC magnetron sputtering. Numerical simulation of the optical properties of the multilayer films has been carried out in order to guide the experimental work. The influences of the ZnO and Cu layer thicknesses, and of O 2 /Ar ratio on the photoelectric and structural properties of the films were investigated. The optical and electrical properties of the multilayers were studied by optical spectrometry and four point probe measurements, respectively. The structural properties were investigated using X-ray diffraction. The performance of the multilayers as transparent conducting coatings was compared using a figure of merit. In experiments, the thickness of the ZnO layers was varied between 4 and 70 nm and those of Cu were between 8 and 37 nm. The O 2 /Ar ratios range from 1:5 to 2:1. Low sheet resistance and high transmittance were obtained when the film was prepared using an O 2 /Ar ratio of 1:4 and a thickness of ZnO (60 nm)/Cu (15 nm)/ZnO (60 nm). - Highlights: ► ZnO/Cu/ZnO films were fabricated from zinc and copper targets by sputtering. ► Transmittance reaches maximum when top and bottom ZnO thicknesses are nearly equal. ► Sheet resistance increases with increasing ZnO layer thickness. ► Variation in sheet resistance with oxygen/argon ratio is due to interface effect.

Au@TiO2 yolk-shell nanostructures for enhanced performance in both photoelectric and photocatalytic solar conversion

Science.gov (United States)

He, Qinrong; Sun, Hang; Shang, Yinxing; Tang, Yanan; She, Ping; Zeng, Shan; Xu, Kongliang; Lu, Guolong; Liang, Song; Yin, Shengyan; Liu, Zhenning

2018-05-01

Solar energy conversion is an important field gaining increasing interest. Herein, bio-inspired Au@TiO2 yolk-shell nanoparticles (NPs) have been prepared via a facial one-pot hydrothermal approach. The Au@TiO2 yolk-shell NPs can self-assemble into 3D-structure to form photoelectrode for photoelectric conversion. The obtained photoelectrode demonstrates a swift and stable photocurrent of 3.5 μA/cm2, which is 4.2 and 1.6 times higher than those of the photocurrents generated by the counterparts of commercial TiO2 and Au@TiO2 core-shell NPs, respectively. Moreover, compared to the commercial TiO2 and Au@TiO2 core-shell NPs, the Au@TiO2 yolk-shell NPs also exhibit superior photocatalytic activity, delivering a H2 evolution rate of 4.92 mmol/g h. The performance improvement observed for the Au@TiO2 yolk-shell NPs is likely contributed by two synergistic factors, i.e. the incorporation of AuNPs and the unique hollow structure, which benefit the activity by simultaneously enhancing light utilization, charge separation and reaction site accessibility. The rational design and fabrication of Au@TiO2 yolk-shell NPs hold great promise for future application in efficient solar energy conversion.

The application of full spectrum gamma-gamma techniques to density/photoelectric cross section logging

International Nuclear Information System (INIS)

Minette, D.C.; Hubner, B.G.; Koudelka, J.C.; Schmidt, M.

1986-01-01

The Compensated Z-Densilog instrument is a new full spectrum gamma-gamma logging instrument, measuring the density and photoelectric cross section (Pe) of the formation. This instrument represents an advancement over present instruments in that the observed gamma spectrum is sent to the surface as a full 256-channel spectrum instead of count rates in a few energy gates. This advancement is made possible by the use of high speed digital electronics which are protected from the high temperatures observed downhole by custom-built flasks. In this paper, the new advanced electronics are considered in some detail. This consideration includes a comparison of full spectrum data acquisition with the multiple discriminator window technique, which is the foundation of the ''few gate'' method. Both of these methods are critiqued based upon electronic stability and the information obtained. The full spectrum provided by high speed electronics facilitates a much more sophisticated data analysis. This data analysis, based on phenomenological model of the instrument (Minette, 1984), includes real time compensation for changes in detector gain and crystal resolution. It also includes a ''four-dimensional'' rib-spine plot, which separates the compensation for mudcake density from the compensation for the Pe of the formation and the mudcake. Also included in the software are real time error minimization and real time decision-making techniques. These techniques maximize the sensitivity of the instrument to the density and Pe of the formation and minimize error due to statistical fluctuations. Gain and resolution compensation completes the data analysis. This compensation virtually eliminates density and Pe errors caused by changing gain and resolution

Optical Properties of Multilayer CdSe/POLYMER Structures

Science.gov (United States)

Red'Ko, V. P.; Voitenkov, A. I.; Kovalenko, O. E.

The effects of preparation condition, concentration and size of particles upon optical and photoelectrical characteristics of multilayer structures CdSe/polyethylene terephthalate obtained by electron-beam evaporation were investigated.

Characteristics of Multihole Collimator Gamma Camera Simulation Modeled Using MCNP5

International Nuclear Information System (INIS)

Saripan, M. I.; Mashohor, S.; Adnan, W. A. Wan; Marhaban, M. H.; Hashim, S.

2008-01-01

This paper describes the characteristics of the multihole collimator gamma camera that is simulated using the combination of the Monte Carlo N-Particles Code (MCNP) version 5 and in-house software. The model is constructed based on the GCA-7100A Toshiba Gamma Camera at the Royal Surrey County Hospital, Guildford, Surrey, UK. The characteristics are analyzed based on the spatial resolution of the images detected by the Sodium Iodide (NaI) detector. The result is recorded in a list-mode file referred to as a PTRAC file within MCNP5. All pertinent nuclear reaction mechanisms, such as Compton and Rayleigh scattering and photoelectric absorption are undertaken by MCNP5 for all materials encountered by each photon. The experiments were conducted on Tl-201, Co-57, Tc-99 m and Cr-51 radio nuclides. The comparison of full width half maximum value of each datasets obtained from experimental work, simulation and literature are also reported in this paper. The relationship of the simulated data is in agreement with the experimental results and data obtained in the literature. A careful inspection at each of the data points of the spatial resolution of Tc-99 m shows a slight discrepancy between these sets. However, the difference is very insignificant, i.e. less than 3 mm only, which corresponds to a size of less than 1 pixel only (of the segmented detector)

Stability and linearity control of spectrometric channels of the Cherenkov counters using controllable units

International Nuclear Information System (INIS)

Kollar, D.; Kollarova, L.; Khorvat, P.

1976-01-01

A system is elaborated to control stability and linearity of the Cherenkov counter spectrometric channels in an experiment on a magnetic monopole search. Linearity of a light characteristic of a photoelectric multiplier is checked with the help of the calibrated light-strikings of light emitting diodes with flare intensity adjusted by controlling generator voltage across the mercury body. A program algorithm is presented for checking stability and linearity of the Cherenkov counter spectrometric channels which helps to consider the fatigue effects of the photoelectric multiplier resulting from the considerable loads

Investigating the effect of K-characteristic radiation on the performance of nuclear medicine scintillators by Monte Carlo methods

International Nuclear Information System (INIS)

Liaparinos, Panagiotis; Kandarakis, Ioannis; Cavouras, Dionisis; Delis, Harry; Panayiotakis, George

2006-01-01

The aim of this study was to evaluate the effect of K-characteristic radiation on the performance of scintillator crystals incorporated in nuclear medicine detectors (LSO, BGO, GSO). K-characteristic radiation is produced within materials of at least one high atomic number element (e.g. Lu, Gd, Bi). This radiation may either be reabsorbed or it may escape the scintillator. In both cases the light emission efficiency of the scintillator may be affected resulting in either spatial or energy resolution degradation. A computational program, based on Monte Carlo methods, was developed in order to simulate the transport of K-characteristic radiation within the most commonly used scintillator materials. Crystal thickness was allowed to vary from 0.5 up to 15 mm. A monoenergetic pencil beam, with energy varying from 0.60 to 0.511 MeV was considered to fall on the center of the crystal surface. The dominant γ-ray interactions (elastic and inelastic scattering and photoelectric absorption) were taken into account in the simulation. Results showed that, depending on crystal thickness, incident photon energy and scintillator's intrinsic properties (L or K-fluorescence yield, effective atomic number and density), the scintillator's emission efficiency may be significantly reduced and affect spatial or energy resolution

A measuring method of photo-electric cross section. Application to high-Z elements between 40 keV and 220 keV. Measurement of K absorption edge energy of Au, Th, U, Pu

International Nuclear Information System (INIS)

Chartier, J.-L.

1977-09-01

This study first describes a bent crystal monochromator developed for the production of monochromatic beams in a continuous energy range from 30 to 250 keV; it is completed by a metrological application of the device (determination of K absorption edge energy of Au, Th, U, Pu). A method and the associated experimental procedure were developed to measure the photo-electric cross section for high-Z elements; the results are presented with a relative uncertainty ranging between 3 and 6%. Finally, the experimental values are compared with values calculated from theories using self-consistent potential models [fr

Qualitative and quantitative analysis of an additive element in metal oxide nanometer film using laser induced breakdown spectroscopy.

Science.gov (United States)

Xiu, Junshan; Liu, Shiming; Sun, Meiling; Dong, Lili

2018-01-20

The photoelectric performance of metal ion-doped TiO 2 film will be improved with the changing of the compositions and concentrations of additive elements. In this work, the TiO 2 films doped with different Sn concentrations were obtained with the hydrothermal method. Qualitative and quantitative analysis of the Sn element in TiO 2 film was achieved with laser induced breakdown spectroscopy (LIBS) with the calibration curves plotted accordingly. The photoelectric characteristics of TiO 2 films doped with different Sn content were observed with UV visible absorption spectra and J-V curves. All results showed that Sn doping could improve the optical absorption to be red-shifted and advance the photoelectric properties of the TiO 2 films. We had obtained that when the concentration of Sn doping in TiO 2 films was 11.89  mmol/L, which was calculated by the LIBS calibration curves, the current density of the film was the largest, which indicated the best photoelectric performance. It indicated that LIBS was a potential and feasible measured method, which was applied to qualitative and quantitative analysis of the additive element in metal oxide nanometer film.

Effects of vacuum heat treatment on the photoelectric work function and surface morphology of multilayered silver–metal electrical contacts

International Nuclear Information System (INIS)

Akbi, Mohamed; Bouchou, Aïssa; Zouache, Noureddine

2014-01-01

Contact materials used for electrical breakers are often made with silver alloys. Mechanical and thermodynamical properties as well as electron emission of such complicated alloys present a lack of reliable and accurate experimental data. This paper deals mainly with electron work function (EWF) measurements about silver–metal (Ag–Me) electrical contacts (Ag–Ni (60/40) and Ag–W (50/50)), before and after surface heat treatments at 513 K–873 K, under UHV conditions (residual gas pressure of 1.4 × 10 −7 mbar). The electron work function (EWF) of silver alloyed contacts was measured photoelectrically, using both Fowler's method of isothermal curves and linearized Fowler plots. An interesting fact brought to light by this investigation is that after vacuum heat treatments, the diffusion and/or evaporation phenomena, affecting the atomic composition of the alloy surface, somehow confine the EWF of the silver–nickel alloy, Φ(Ag–Ni), determined at room temperature in interval]Φ(Ag), Φ(Ni) [=] 4.26 eV, 4.51 eV[. Surface analysis of two specimens before and after heating showed a significant increase of tungsten atomic proportion on the contact surface for Ag–W contacts after VH treatments. A multilayer model, taking into account the strong intergranular and volume segregation gives a good interpretation of the obtained results.

Effects of Nb doping level on the electronic transport, photoelectric effect and magnetoresistance across La0.5Ca0.5MnO3/Nb:SrTiO3 junctions

Science.gov (United States)

Wang, J. F.; Jiang, Y. C.; Chen, M. G.; Gao, J.

2013-12-01

Heterojunctions composed of La0.5Ca0.5MnO3 and Nb doped SrTiO3 were fabricated, and the effects of the Nb doping level on their electronic transport, photoelectric effect, and magnetoresistance were investigated. A lower doping concentration of Nb led to better rectifying properties and higher open circuit voltages. The I-V curves for La0.5Ca0.5MnO3/0.7 wt. % Nb-SrTiO3 showed a negligible response to magnetic fields for all temperatures, whereas La0.5Ca0.5MnO3/0.05 wt. % Nb-SrTiO3 exhibited distinct magnetoresistance, which depended on both the bias voltage and temperature. These results are discussed with the assistance of conventional semiconductor theories.

Analysis of subnanosecond fluorescence decay curves with a 5GHz real time detection system

International Nuclear Information System (INIS)

Cunin, B.; Heisel, F.; Knispel, G.; Miehe, J.A.; Sipp, B.

1975-01-01

This paper presents a detailed description and a review on the characteristics of a fast vacuum photoelectric cell associated with a high speed cathode ray tube. In addition, this system is used to measure short-lived fluorescence decay times [fr

A proteorhodopsin-based biohybrid light-powering pH sensor.

Science.gov (United States)

Rao, Siyuan; Guo, Zhibin; Liang, Dawei; Chen, Deliang; Wei, Yen; Xiang, Yan

2013-10-14

The biohybrid sensor is an emerging technique for multi-functional detection that utilizes the instinctive responses or interactions of biomolecules. We develop a biohybrid pH sensor by taking advantage of the pH-dependent photoelectric characteristics of proteorhodopsin (pR). The transient absorption kinetics study indicates that the photoelectric behavior of pR is attributed to the varying lifetime of the M intermediate at different environmental pH values. This pR-based biohybrid light-powering sensor with microfluidic design can achieve real-time pH detection with quick response and high sensitivity. The results of this work would shed light on pR and its potential applications.

B and V photoelectric photometry and light curve solution of the interacting binary systems HI Puppis, BL Eridani and SY Horologii

International Nuclear Information System (INIS)

Kern, J.R.

1985-01-01

The first photoelectric observations of the eclipsing binary systems HI Puppis, BL Eridani, and SY Horologii were obtained and complete B and V light curves are presented. Improved light elements were derived for all three systems. The light curves of HI Puppis were analyzed by the three different computer models of Wilson and Devinney (1971), Binnendijk (1977), and Wood (1971) to get the geometrical and photometric elements of the system. HI Puppis, whose light curves show a total eclipse at secondary minimum, is shown to be a classic A-Type W Ursae Majoris system. The geometrical and photometric elements of BL Eridani were obtained from the analysis of the light curves using the method of Wilson and Devinney. The asymmetric nature of the light curve is treated as being due to the presence of an underluminous starspot on the primary component. The light curves of BL Eri show secondary eclipse to be total. The system is found to be a near contact system with the primary component filling its Roche lobe and the secondary nearly filling its lobe with a fill-out ratio of approximately 1.0. The light curves of SY Horologii were also subjected to the model of Wilson and Devinney. Both primary and secondary eclipses are partial

Features of the low-power charge controller of lead-acid current sources charged by solar batteries

International Nuclear Information System (INIS)

Tukfatullin, O.F.; Yuldoshev, I.A.; Solieva, N.A.

2008-01-01

Influence of different factors on exploitations characteristics of solar photoelectric plant is investigated by field-performance data. A construction of charge controller of the lead-acid accumulator battery charging by means of solar battery is analyzed taking into account these factors. (authors)

Immobilizing ternary Zn{sub X}Cd{sub 1−X}S on graphene via solvothermal method for enhanced photoelectric properties

Energy Technology Data Exchange (ETDEWEB)

Lei, Yun, E-mail: leiyun@whut.edu.cn; Chen, Feifei; Xu, Jun

2015-12-01

Graphical abstract: - Highlights: • Composition-tunable Zn{sub X}Cd{sub 1−X}S-graphene were prepared with a one-step solvothermal process by varying Zn/Cd ratios. • The diffraction peaks move to higher angle and UV–vis spectra present a progressive blue-shift with the increase of x value. • A more efficient separation of photo-induced carriers and a faster interfacial charge transfer occurs on graphene-Zn{sub 0.8}Cd{sub 0.2}S. - Abstract: Ternary Zn{sub X}Cd{sub 1−X}S particles were directly immobilized on graphene sheets by a facile solvothermal route with zinc acetate, cadmium acetate and thiourea as precursors, ethylene glycol as reaction solvent and graphene oxide as support. The value of x could be adjusted by controlling the molar ratio of Zn and Cd precursors. The products were characterized by X-ray diffraction, scanning electron microscope and ultraviolet–visible absorption. The photoelectric properties of the graphene-Zn{sub X}Cd{sub 1−X}S composites were investigated by transient photocurrent responses and electrochemical impedance spectra, and the results show that the obvious increase in the photocurrent density and decrease in electron-transfer resistance can be seen for graphene-Zn{sub 0.8}Cd{sub 0.2}S composites as compared to graphene-Zn{sub X}Cd{sub 1−X}S composites with other Zn/Cd ratios.

Concept of dual-resolution light field imaging using an organic photoelectric conversion film for high-resolution light field photography.

Science.gov (United States)

Sugimura, Daisuke; Kobayashi, Suguru; Hamamoto, Takayuki

2017-11-01

Light field imaging is an emerging technique that is employed to realize various applications such as multi-viewpoint imaging, focal-point changing, and depth estimation. In this paper, we propose a concept of a dual-resolution light field imaging system to synthesize super-resolved multi-viewpoint images. The key novelty of this study is the use of an organic photoelectric conversion film (OPCF), which is a device that converts spectra information of incoming light within a certain wavelength range into an electrical signal (pixel value), for light field imaging. In our imaging system, we place the OPCF having the green spectral sensitivity onto the micro-lens array of the conventional light field camera. The OPCF allows us to acquire the green spectra information only at the center viewpoint with the full resolution of the image sensor. In contrast, the optical system of the light field camera in our imaging system captures the other spectra information (red and blue) at multiple viewpoints (sub-aperture images) but with low resolution. Thus, our dual-resolution light field imaging system enables us to simultaneously capture information about the target scene at a high spatial resolution as well as the direction information of the incoming light. By exploiting these advantages of our imaging system, our proposed method enables the synthesis of full-resolution multi-viewpoint images. We perform experiments using synthetic images, and the results demonstrate that our method outperforms other previous methods.

Molecular semiconductors photoelectrical properties and solar cells

CERN Document Server

Rees, Ch

1985-01-01

During the past thirty years considerable efforts have been made to design the synthesis and the study of molecular semiconductors. Molecular semiconductors - and more generally molecular materials - involve interactions between individual subunits which can be separately synthesized. Organic and metallo-organic derivatives are the basis of most of the molecular materials. A survey of the literature on molecular semiconductors leaves one rather confused. It does seem to be very difficult to correlate the molecular structure of these semiconductors with their experimental electrical properties. For inorganic materials a simple definition delimits a fairly homogeneous family. If an inorganic material has a conductivity intermediate between that of an 12 1 1 3 1 1 insulator « 10- n- cm- ) and that of a metal (> 10 n- cm- ), then it is a semiconductor and will exhibit the characteristic properties of this family, such as junction formation, photoconductivity, and the photovoltaic effect. For molecular compounds,...

Report on the FY 1999 R and D survey on ultra-high sensitive photoelectric converter; 1999 nendo chokokando koden henkan soshi ni kansuru kenkyu kaihatsu chosa hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

By the ICB method which is one of the ion engineering methods, photomultipliers were formed using organic dye thin films. By changing the energy to bond traps on thin film/metal electrode interface and electric charges by change of acceleration energy of ion beams, a technology was developed for adjusting the optimum operating temperature between -20 degrees C and +100 degrees C. The wide range of operating temperature and favorable SN ratio can be realized. It was made clear that the dark current of the photomultiplier is composed of two components of contribution by the residual charge stored on the interface at photomultiplying and of contribution by charge injection from the Schottky barrier. Based on this, the residual electric charge removal method by heating and applied pulse voltage was developed. The development for practical use was studied of ultra-high sensitive photoelectric converters. As an intelligent photo sensor, a biomimetic visual photosensor was proposed which uses amplification/memory/arithmetic functions and film formation/processability of organic thin films. The paper also described the image sensor. (NEDO)

Optical timing receiver for the NASA laser ranging system. Part I. Constant-fraction discriminator

International Nuclear Information System (INIS)

Leskovar, B.; Lo, C.C.

1975-01-01

Position-resolution capabilities of the NASA laser ranging system are essentially determined by time-resolution capabilities of its optical timing receiver. The optical timing receiver consists of a fast photoelectric device, primarily a standard of microchannel-plate-type photomultiplier or an avalanche photodiode detector, a timing discriminator, a high-precision time-interval digitizer, and a signal-processing system. The time-resolution capabilities of the receiver are determined by the photoelectron time spread of the photoelectric device, the time walk and resolution characteristics of the timing discriminator, and the time-interval digitizer. It is thus necessary to evaluate available fast photoelectronic devices with respect to their time-resolution capabilities, and to design a very low time walk timing discriminator and a high-precision time digitizer which will be used in the laser ranging system receiver. (auth)

Enhanced Response Speed of ZnO Nanowire Photodetector by Coating with Photoresist

Directory of Open Access Journals (Sweden)

Xing Yang

2016-01-01

Full Text Available Spin-coating photoresist film on ZnO nanowire (NW was introduced into the fabrication procedure to improve photoresponse and recovery speed of a ZnO NW ultraviolet photoelectric detector. A ZnO NW was first assembled on prefabricated electrodes by dielectrophoresis. Then, photoresist was spin-coated on the nanowire. Finally, a metal layer was electrodeposited on the nanowire-electrode contacts. The response properties and I-V characteristics of ZnO NW photodetector were investigated by measuring the electrical current under different conditions. Measurement results demonstrated that the detector has an enhanced photoresponse and recovery speed after coating the nanowire with photoresist. The photoresponse and recovery characteristics of detectors with and without spin-coating were compared to demonstrate the effects of photoresist and the enhancement of response and recovery speed of the photodetector is ascribed to the reduced surface absorbed oxygen molecules and binding effect on the residual oxygen molecules after photoresist spin-coating. The results demonstrated that surface coating may be an effective and simple way to improve the response speed of the photoelectric device.

Retail Lamps Study 3.1: Dimming, Flicker, and Power Quality Characteristics of LED A Lamps

Energy Technology Data Exchange (ETDEWEB)

Royer, Michael P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Poplawski, Michael E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Brown, Charles C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2014-12-01

To date, all three reports in the retail lamps series have focused on basic performance parameters, such as lumen output, efficacy, and color quality. This report goes a step further, examining the photoelectric characteristics (i.e., dimming and flicker) of a subset of lamps from CALiPER Retails Lamps Study 3. Specifically, this report focuses on the dimming, power quality, and flicker characteristics of 14 LED A lamps, as controlled by four different retail-available dimmers. The results demonstrate notable variation across the various lamps, but little variation between the four dimmers. Overall, the LED lamps: ~tended to have higher relative light output compared to the incandescent and halogen benchmark at the same dimmer output signal (RMS voltage). The lamps’ dimming curves (i.e., the relationship between control signal and relative light output) ranged from linear to very similar to the square-law curve typical of an incandescent lamp. ~generally exhibited symmetrical behavior—the same dimming curve—when measured proceeding from maximum to minimum or minimum to maximum control signal. ~mostly dimmed below 10% of full light output, with some exceptions for specific lamp and dimmer combinations ~exhibited a range of flicker characteristics, with many comparing favorably to the level typical of a magnetically-ballasted fluorescent lamp through at least a majority of the dimming range. ~ always exceeded the relative (normalized) efficacy over the dimming range of the benchmark lamps, which rapidly decline in efficacy when they are dimmed. This report generally does not attempt to rank the performance of one product compared to another, but instead focuses on the collective performance of the group versus conventional incandescent or halogen lamps, the performance of which is likely to be the baseline for a majority of consumers. Undoubtedly, some LED lamps perform better—or more similar to conventional lamps—than others. Some perform desirably for one

The effect of twisted D–D–π–A configuration on electron transfer and photo-physics characteristics

Science.gov (United States)

Liu, Yunpeng; Li, Yuanzuo; Song, Peng; Ma, Fengcai; Yang, Yanhui

2018-05-01

Two D-D-π-A organic dyes (M45, M46) with dithieno[3,2-b:2‧,3‧-d]pyrrole (DTP) units as election donors in two perpendicular directions, were investigated using density functional theory (DFT) and time-dependent DFT. The ground-state geometries, the absorption, the electronic structures, the charge density difference and molecular electrostatic potential were obtained. To simulate a more realistic performance, all calculations were based on gas condition and dichloromethane solvent. Photoelectric parameters were evaluated by the following factors: the light harvesting efficiency, electron injection driving force, the excited lifetime and vertical dipole moment. Meanwhile, the polarisability and hyperpolarisability were investigated to further explain the relationship between non-linear optical properties and efficiency. The direction of the DTP obviously affects the twisted degree of molecule, forming a better coplanarity on the donor 2 of M45, which results in stronger charge transfer interactions. Furthermore, M45 possesses significant advantages in geometric structure, absorption band and intramolecular charge transfer mechanism. These critical parameters supported the higher performance of M45 in comparison with M46. Moreover, four dyes were designed by the substitution of donor 2, which further verify the influence of the twisted donor 2 on electron transfer and photoelectric properties of D-D-π-A configuration.

Journal of Astrophysics and Astronomy | Indian Academy of Sciences

Indian Academy of Sciences (India)

2016-01-27

Jan 27, 2016 ... Here we report the spectral characteristics of the high and low states of the pulsar 4U 0114+65 and examine the change in the parameters of the spectral model. A power lawand a photoelectric absorption by material along the line of sight together with a high energy cut-off suffice to describe the continuum ...

Photoelectric guided AGV based on MC9S12XS128MAL%基于MC9S12XS128MAL控制的光电导引式AGV

Institute of Scientific and Technical Information of China (English)

刘波; 汪宇辰; 梁伟健; 叶波; 周杰

2013-01-01

Aiming at the drawbacks that automatic guided vehicles (AGV) are bulky and expensive,a system based on Freescale micro processor Mc9S12XS128MAL was used to design the economic photoelectric guided AGV system with the sophisticated intelligent car racing of the Froescale cup and the cheep electric wheelchairs.Experimental study on the ultrosonic sensors was carried out on a test rig.The obastacle distance in emergency was measured experimentally.The LCD module was introduced to display the real time velocity with using photoelectric encoders.Two brushless DC motors were used to drive the wheels,the deviation accumulated algorithm was proposed,The function was realized that the brushless DC motors successfully drive the AGV forward and to turn through differential control.At last,the control method was validated in the experiment.The results indicate that the AGV system is of quick dynamic response and stable operation,and the automatic control of the AGV is excellently realized.%针对目前国内自动导引运输车(AGV)体积大、价格贵的问题,在技术成熟的“飞思卡尔”智能汽车竞赛和价格低廉的电动轮椅车的基础上,设计了一款基于“飞思卡尔”MC9S12XS128MAL微处理器控制的经济型光电导引式AGV系统.在试验台上对超声波传感器进行了测试,确定了紧急情况下的避障距离；采用光电码盘测速,由液晶模块显示出AGV的实时速度；同时结合无刷直流电机驱动原理,提出了基于偏差累积算法的控制方法,实现了差动方式的无刷直流电机驱动AGV直线行驶和转弯的功能,最后通过实验验证了该控制方法的有效性.研究结果表明,此AGV系统响应迅速、运行稳定,很好地实现了AGV的自动控制.

Slow-Photon-Effect-Induced Photoelectrical-Conversion Efficiency Enhancement for Carbon-Quantum-Dot-Sensitized Inorganic CsPbBr3 Inverse Opal Perovskite Solar Cells.

Science.gov (United States)

Zhou, Shujie; Tang, Rui; Yin, Longwei

2017-11-01

All-inorganic cesium lead halide perovskite is suggested as a promising candidate for perovskite solar cells due to its prominent thermal stability and comparable light absorption ability. Designing textured perovskite films rather than using planar-architectural perovskites can indeed optimize the optical and photoelectrical conversion performance of perovskite photovoltaics. Herein, for the first time, this study demonstrates a rational strategy for fabricating carbon quantum dot (CQD-) sensitized all-inorganic CsPbBr 3 perovskite inverse opal (IO) films via a template-assisted, spin-coating method. CsPbBr 3 IO introduces slow-photon effect from tunable photonic band gaps, displaying novel optical response property visible to naked eyes, while CQD inlaid among the IO frameworks not only broadens the light absorption range but also improves the charge transfer process. Applied in the perovskite solar cells, compared with planar CsPbBr 3 , slow-photon effect of CsPbBr 3 IO greatly enhances the light utilization, while CQD effectively facilitates the electron-hole extraction and injection process, prolongs the carrier lifetime, jointly contributing to a double-boosted power conversion efficiency (PCE) of 8.29% and an increased incident photon-to-electron conversion efficiency of up to 76.9%. The present strategy on CsPbBr 3 IO to enhance perovskite PCE can be extended to rationally design other novel optoelectronic devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Structural and optical features of state-of-the-art industrial solar cells and units on their basis

International Nuclear Information System (INIS)

Bykov, M.; Mazinov, A.; Bykov, A.

2005-01-01

In this paper presenting experimental research for solar energy production the day time is defined, using state-of-the-art industrial photo-electric converters (PEC) on the basis of crystalline silicon. Based on the obtained practical results, it has been constructed an experimental solar energy device. The device has been tested for a year and and its characteristics have been investigated

Annealing effect on I-V characteristic of n-ZnO-p-InSe heterojunction

Directory of Open Access Journals (Sweden)

Kovalyuk Z. D.

2015-12-01

Full Text Available The article is devoted to studying of influence of vacuum low-temperature annealing on the electrical and photoelectric characteristics of n-ZnO-p-InSe heterostructure. Indium monoselenide (InSe is a semiconductor of the A3B6 group of layered compounds. The basic unit consists of two planes of metal atoms sandwiched between two planes of chalcogen atoms (Se-In-In-Se. The absence of dangling bonds on InSe cleaved surface makes it possible to use this semiconductor as a substrate for fabrication of heterostructures based on semiconductor materials with different symmetries and lattice spacings. Zinc oxide (ZnO is the most suitable material for window materials and solar cells buffer layers application due to its marvelous transparency in the range of visible region. InSe single crystals were grown by the Bridgman technique from a nonstoichiometric melt and characterized by a pronounced layered structure along the whole length of a sample. ZnO thin oxide film was formed on freshly cleaved van der Waals surface of InSe layered crystal. n-ZnO-p-InSe heterostructure was prepared by the method of high-frequency magnetron sputtering. Sensitivity spectral areas were identified by MDR-3 monochromator with a resolution of 2.6 nm/mm. The current-voltage characteristics of the n-ZnO-p-InSe heterostructures showed a clearly pronounced diode character. In the forward bias of the initial samples, the diode factor had the value 3.7 at room temperature. It is shown that vacuum low-temperature annealing reduces shunt currents of the heterojunction, which is reflected in the decrease in the values of n from 3.7 to 2.7.

Signal processing in an acousto-optical spectral colorimeter

Science.gov (United States)

Emeljanov, Sergey P.; Kludzin, Victor V.; Kochin, Leonid B.; Medvedev, Sergey V.; Polosin, Lev L.; Sokolov, Vladimir K.

2002-02-01

The algorithms of spectrometer signals processing in the acousto-optical spectral colorimeter, proposed earlier are discussed. This processing is directional on distortion elimination of an optical system spectral characteristics and photoelectric transformations, and also for calculation of tristimulus coefficients X,Y,Z in an international colorimetric system of a CIE - 31 and transformation them in coordinates of recommended CIE uniform contrast systems LUV and LAB.

Visible Photodetectors Based on Organic-Inorganic Hybrids Using Electrostatic Spraying Technology

Directory of Open Access Journals (Sweden)

Liang-Wen Ji

2013-12-01

Full Text Available This paper discusses an organic-inorganic hybrid white photodetector with the structure of ITO /AZO/ZnO NWs:P3HT: PCBM/PEDOT: PSS/Al produced with an electrostatic spraying method. The method of production was as follows: First, different spraying methods (continuous spraying, discontinuous spraying and different spraying times were tested before the final electrostatic spraying. Then, different annealing times (10 min and 20 min were tested to anneal the coated film. Lastly, we investigated the photoelectric properties, including transparency analysis of the film surface topography through XRD, OM, FE-SEM, AFM and UV-VIS. The results showed that the detector with discontinuous spraying and 20 mins annealing had a photocurrent of approx. 22.1×10-4A, dark current (drain current of approx. 1.94×10-7A, and a ratio of photocurrent to dark current of approximately 1.14×104, which produced optimal photoelectric characteristics.

Electron tube

Science.gov (United States)

Suyama, Motohiro [Hamamatsu, JP; Fukasawa, Atsuhito [Hamamatsu, JP; Arisaka, Katsushi [Los Angeles, CA; Wang, Hanguo [North Hills, CA

2011-12-20

An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

Poly(ethylene glycol)/carbon quantum dot composite solid films exhibiting intense and tunable blue–red emission

International Nuclear Information System (INIS)

Hao, Yanling; Gan, Zhixing; Xu, Jiaqing; Wu, Xinglong; Chu, Paul K.

2014-01-01

Highlights: • Poly(ethylene glycol)/carbon quantum dots (PEG/CQDs) composite solid films exhibiting strong and tunable blue–red emission were prepared. Successful preparation of tunable emitting CQDs solid films can extend the application of carbon quantum dots in photoelectric devices. • The mechanism of the tunable emission from the PEG/CQDs composite solid films was discussed. • On the basis of the characteristics of the PL from solid films in this work, the complex PL origins of CQDs were further defined. The PL mechanism provides insights into the fluorescence mechanism of CQDs and may promotes their applications. • Poly(ethylene glycol); carbon quantum dots; Strong and tunable blue-red emission; The fluorescent quantum yield of 12.6%. - Abstract: Although carbon quantum dots (CQDs) possess excellent luminescence properties, it is a challenge to apply water-soluble CQDs to tunable luminescent devices. Herein, quaternary CQDs are incorporated into poly(ethylene glycol) to produce poly(ethylene glycol)/CQD composite solid films which exhibit strong and tunable blue–red emission. The fluorescent quantum yield reaches 12.6% which is comparable to that of many liquid CQDs and the photoluminescence characteristics are determined to elucidate the fluorescence mechanism. The CQD solid films with tunable optical properties bode well for photoelectric devices especially displays

Future prospects for studies in the VUV-SX region

International Nuclear Information System (INIS)

Tanaka, Kenichiro; Kitajima, Yoshinori

1989-09-01

This book carries papers presented at a workshop 'Future Prospects for Studies in the VUV-SX Region' held on March 22 and 23, 1989. The workshop focussed particularly on the promotion of research in the VUV and soft X-ray regions. Three sessions were held: Session 1 for studies in peripheral areas, Session 2 for theoretical studies, and Session 3 for recent developments. Session 1 covered five studies: 'Laser Spectroscopy: High-Resolution Observation of Highly Electronically Excited Gaseous Molecule', 'High-Resolution Electron Spectroscopy: Surface Phonon Spectroscopy', 'Experimental Study on Atoms and Molecules through Ion Trap', 'Basic Mechanism of Photo-Induced CVD', and 'Application of Circularly Polarized Light'. Session 2 covered five studies: 'Electronic State of High Tc Superconducting Oxide', 'Surface Condition and Electronic State', 'XES and XAS Study of Rare Earth Compound', 'Resonance Photoelectric Spectroscopy on Strongly Correlated Electronic System', and 'Circularly Polarized Light and Atomic Process in Soft X-Ray Region'. Session 3 covered six studies: 'Prospects of Application of Supercritical Liquid to Research on Physical Characteristics', 'Application of Orbit Radiation to Polarization Spectroscopy', 'XES Research for La Compounds', 'Characteristics of Ultra-Fine Particles', 'Surface Study by Angular-Resolution Photoelectric Spectroscopy', and 'EXAFS Study of Light Element'. (N.K.)

Structural, electrical, and photoelectric properties of p-NiO/n-CdTe heterojunctions

Science.gov (United States)

Parkhomenko, Hryhorii; Solovan, Mykhaylo; Brus, Viktor; Maystruk, Eduard; Maryanchuk, Pavlo

2018-01-01

p-NiO/n-CdTe-photosensitive heterojunctions were prepared by the deposition of nickel oxide thin films onto n-type single-crystal CdTe substrates by DC reactive magnetron sputtering. The analysis of capacitance-voltage (C-V) characteristics, measured at different frequencies of the small amplitude AC signal and corrected by the effect of the series resistance, provided evidence of the presence of electrically charged interface states, which significantly affect the measured capacitance. The dominant current transport mechanisms in the heterojunctions were determined at forward and reverse biases. Using "light" I-V characteristics, we determined the open-circuit voltage Voc=0.42 V, the short-circuit current Isc=57.5 μA/cm2, and the fill factor FF=0.24 under white light illumination with the intensity of 80 mW.

Effect of boron implantation on the electrical and photoelectrical properties of e-beam deposited Ag-In-Se thin films

International Nuclear Information System (INIS)

Colakoglu, T; Parlak, M; Kulakci, M; Turan, R

2008-01-01

In this study, e-beam evaporated Ag-In-Se (AIS) thin films were doped by the implantation of boron (B) ions at 75 keV with a dose of 1 x 10 15 ions cm -2 and a subsequent annealing process was applied to the doped AIS films at different temperatures under nitrogen atmosphere. The effects of implantation and annealing on the electrical and photoelectrical properties of AIS thin films were investigated through temperature dependent conductivity, spectral photoresponse and photoconductivity measurements under different illumination intensities. The electrical conductivity measurements showed that the room temperature conductivity values were determined as 2.4 x 10 -7 (Ω cm) -1 , 1.7 x 10 -6 (Ω cm) -1 and 8.9 x 10 -5 (Ω cm) -1 for B-doped films (B0), B-doped and annealed films at 200 deg. C (B2) and at 300 deg. C (B3), respectively. It was observed that the electrical conductivity improved as the annealing temperature increased up to 400 deg. C at which the AIS thin films showed degenerate semiconductor behaviour. The spectral distribution of the photoresponse curves indicated three local maxima located at 1.63, 1.79 and 2.01 eV for B0 type films, 1.65, 1.87 and 2.07 eV for B2 type films and 1.73, 2.02 and 2.32 eV for B3 type films at room temperature. These three different energy values were ascribed to the splitting of the valence band due to spin-orbit interaction and crystalline lattice field effects. The first energy values of each set were determined to be energy band gaps of the AIS thin films. The photoconductivity measurements as a function of temperature and illumination intensity were performed on the B-doped AIS thin films in order to determine the nature of recombination processes in the films. The photoconductivity values were found to be thermally quenched for all types of thin films and the variation of photocurrent as a function of illumination intensity showed that the dependence of photocurrent on the intensity was supralinear. The two

High-Sensitive Two-Layer Photoresistors Based on p-Cd x Hg1-x Te with a Converted Near-Surface Layer

Science.gov (United States)

Ismailov, N. D.; Talipov, N. Kh.; Voitsekhovskii, A. V.

2018-04-01

The results of an experimental study of photoelectric characteristics of two-layer photoresistors based on p-Cd x Hg1-x Te (x = 0.24-0.28) with a thin near-surface layer of n-type obtained by treatment in atmospheric gas plasma are presented. It is shown that the presence of a potential barrier between the p- and n-regions causes high photosensitivity and speed of operation of such photoresistors at T = 77 K

High-Sensitive Two-Layer Photoresistors Based on p-Cd x Hg1- x Te with a Converted Near-Surface Layer

Science.gov (United States)

Ismailov, N. D.; Talipov, N. Kh.; Voitsekhovskii, A. V.

2018-04-01

The results of an experimental study of photoelectric characteristics of two-layer photoresistors based on p-Cd x Hg1- x Te (x = 0.24-0.28) with a thin near-surface layer of n-type obtained by treatment in atmospheric gas plasma are presented. It is shown that the presence of a potential barrier between the p- and n-regions causes high photosensitivity and speed of operation of such photoresistors at T = 77 K

Structure for collimated scintillation detectors, that can be used in tomography

International Nuclear Information System (INIS)

1979-01-01

Structures for containing and supporting scintillator bodies are disclosed in which the optical output of the scintillator body is channeled by light reflective means to photoelectrically responsive devices mounted on the top and bottom of the detector array. In accordance with one embodiment of the invention, the internal surfaces of the collimating array are coated with either a diffuse or specular reflective coating. In accordance with another embodiment of the invention, the photoelectrically responsive transducers are located at the top and bottom of the array rather than at the rear. In accordance with another embodiment of the invention, reflective light channeling wedges are provided to improve spacing requirements for the photoelectrically responsive transducers. The scintillator structures of the present invention provide superior optical coupling to photoelectrically responsive devices. (Auth.)

Exploration and practice in-class practice teaching mode

Science.gov (United States)

Zang, Xue-Ping; Wu, Wei-Feng

2017-08-01

According to the opto-electronic information science and engineering professional course characteristics and cultivate students' learning initiative, raised the teaching of photoelectric professional course introduce In-class practice teaching mode. By designing different In-class practice teaching content, the students' learning interest and learning initiative are improved, deepen students' understanding of course content and enhanced students' team cooperation ability. In-class practice teaching mode in the course of the opto-electronic professional teaching practice, the teaching effect is remarkable.

Investigation of the limitations of the highly pixilated CdZnTe detector for PET applications.

Science.gov (United States)

Komarov, Sergey; Yin, Yongzhi; Wu, Heyu; Wen, Jie; Krawczynski, Henric; Meng, Ling-Jian; Tai, Yuan-Chuan

2012-11-21

We are investigating the feasibility of a high resolution positron emission tomography (PET) insert device based on the CdZnTe detector with 350 µm anode pixel pitch to be integrated into a conventional animal PET scanner to improve its image resolution. In this paper, we have used a simplified version of the multi pixel CdZnTe planar detector, 5 mm thick with 9 anode pixels only. This simplified 9 anode pixel structure makes it possible to carry out experiments without a complete application-specific integrated circuits readout system that is still under development. Special attention was paid to the double pixel (or charge sharing) detections. The following characteristics were obtained in experiment: energy resolution full-width-at-half-maximum (FWHM) is 7% for single pixel and 9% for double pixel photoelectric detections of 511 keV gammas; timing resolution (FWHM) from the anode signals is 30 ns for single pixel and 35 ns for double pixel detections (for photoelectric interactions only the corresponding values are 20 and 25 ns); position resolution is 350 µm in x,y-plane and ∼0.4 mm in depth-of-interaction. The experimental measurements were accompanied by Monte Carlo (MC) simulations to find a limitation imposed by spatial charge distribution. Results from MC simulations suggest the limitation of the intrinsic spatial resolution of the CdZnTe detector for 511 keV photoelectric interactions is 170 µm. The interpixel interpolation cannot recover the resolution beyond the limit mentioned above for photoelectric interactions. However, it is possible to achieve higher spatial resolution using interpolation for Compton scattered events. Energy and timing resolution of the proposed 350 µm anode pixel pitch detector is no better than 0.6% FWHM at 511 keV, and 2 ns FWHM, respectively. These MC results should be used as a guide to understand the performance limits of the pixelated CdZnTe detector due to the underlying detection processes, with the understanding of

Enhancement of radiation cytotoxicity by gold nanoparticles in MCF-7 breast cancer cell lines

Energy Technology Data Exchange (ETDEWEB)

Rosli, Nur Shafawati binti; Rahman, Azhar Abdul [School of Physics, Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); Aziz, Azlan Abdul [School of Physics, Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); Nano-Biotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); Shamsuddin, Shaharum [Nano-Biotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia)

2015-04-24

Therapy combined with metallic nanoparticles is a new way to treat cancer, in which gold nanoparticles (AuNPs) are injected through intravenous administration and bound to tumor sites. Radiotherapy aims to deliver a high therapeutic dose of ionizing radiation to the tumor without exceeding normal tissue tolerance. The use of AuNPs which is a high-atomic-number (Z) material in radiotherapy will provide a high probability for photon interaction by photoelectric effect. These provide advantages in terms of radiation dose enhancement. The high linear energy transfer and short range of photoelectric interaction products (photoelectrons, characteristic x-rays, Auger electrons) produce localized dose enhancement of the tumor. In this work, breast cancer cell lines (MCF-7) are seeded in the 96-well plate and were treated with 13 nm AuNPs before they were irradiated with 6 MV and 10 MV photon beam from a medical linear accelerator at various radiation doses. To validate the enhanced killing effect, both with and without AuNPs MCF-7 cells is irradiated simultaneously. By comparison, the results show that AuNPs significantly enhance cancer killing.

New Sunshine Program for fiscal 2000. Development of photovoltaic power system commercialization technology (Development of ultrahigh-efficiency crystalline compound solar cell manufacturing technology - Surveys and studies of peripheral key technologies/Feasibility study of wet-type solar cell commercialization); 2000 nendo New sunshine keikaku seika hokokusho. Taiyoko hatsuden system jitsuyoka gijutsu kaihatsu - Chokokoritsu kessho kagobutsu taiyo denchi no seizo gijutsu kaihatsu, Shuhen yoso gijutsu ni kansuru chosa kenkyu - Shissiki taiyo denchi jitsuyoka kanosei chosa

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Dye-sensitized solar cell commercialization was studied for feasibility. Studies were made about photoelectric conversion efficiency and various factors supposedly to affect the life and other properties, and a wet-type (dye-sensitized type) solar cell was fabricated. In an endurance test, the dye-sensitized solar cell retained its initial performance after 3,500 hours of continuous irradiation. A 16 cm{sup 2}-large integrated type Graetzel cell was fabricated, and it achieved a photoelectric conversion efficiency of 4.6%. Furthermore, in the study of Graetzel cells, possibility of the creation of new electrolytic solutions was discussed, a non-TiO{sub 2} dye-sensitized solar cell was fabricated based on the self-assembled electrodeposition of the ZnO dye, and the feasibility was deliberated of a dye-sensitized solar sell using a composite oxide semiconductor. Concerning their development in the future, it was concluded that dye-sensitized solar cells including the Graetzel cell were equipped with the basic characteristics of a next-generation solar cell that would be requested to be low in cost and high in performance. (NEDO)

Cognition and thinking on Applied Optics course's reformation and innovation

Science.gov (United States)

Chen, Jingjing; Ji, Feng; Liu, Zhijian; Xia, Haojie; Shu, Shuangbao

2017-08-01

The course of "Applied Optics" is professional and foundational for the specialty of photo-electric information and engineering. According to the characteristics of the specialty, the teaching contents, teaching means, innovations and appraisal methods are mainly discussed in this paper. Firstly, one of the most difficult part to comprehend, the Fermat principle is taken as an example in the teaching content. By using the development history of optics and interesting natural phenomenon, students' understanding of the optical knowledge can be enhanced. Secondly, in various means of teaching art, ZEMAX provides students with a platform of training innovative consciousness and engineering capacity, and it make high cohesion in teaching and scientific research. Thirdly, in the teaching innovation, photoelectric contest can stimulate students' innovative thinking, innovation awareness, and cultivate undergraduate students' optics, mechanics, electricity, numerology integrated design capabilities. Lastly, the reform in the appraisal methods guide students from focusing on the examination results to pay attention to the learning process. Eventually, students' study interest has improved, demand of the engineering practice has adapted, and the well teaching effect has realized.

Photovoltaic modules with cylindrical waveguides in a system for the secondary concentration of solar radiation

Science.gov (United States)

Andreev, V. M.; Davidyuk, N. Yu.; Ionova, E. A.; Rumyantsev, V. D.

2013-09-01

The parameters of the concentrating photoelectric modules with triple-junction (InGaP/GaAs/Ge) solar cells whose focusing system contains an original secondary optical element are studied. The element consists of a plane-convex lens in optical contact with the front surface of an intermediate glass plate and a cylindrical waveguide that is located on the rear side of the glass plate above the surface of the solar element. It is demonstrated that the structure of the secondary optical element provides a wide misorientation characteristic of the concentrator and the cylindrical waveguide allows a more uniform radiation density over the surface of the solar cell. The effect of chromatic aberration in the primary and secondary optical systems on the parameters of photoelectric modules is analyzed. It is demonstrated that the presence of waveguides with a length of 3-5 mm leads to effective redistribution of radiation over the surface of the solar cell whereas shorter and longer waveguides provide the local concentration of radiation at the center of the photodetecting area.

The smoke sensor and its use

International Nuclear Information System (INIS)

Zhou Changgeng

1998-01-01

The authors have introduced the working principle of a new smoke sensor. Good prospects of the photoelectricity smoke detector are described. It has been pointed out that the photoelectrical smoke detector will become the major products of the fire detecting

Recombination and photosensitivity centres in boron nitride irradiated with ions

International Nuclear Information System (INIS)

Kabyshev, A.; Konusov, F.; Lopatin, V.

2001-01-01

The physical-chemical processes, taking place during the irradiation of dielectrics with ions distort the electron structure of the compounds and generate additional localise state in the forbidden zone (FZ). Consequently, the semiconductor layer with the specific surface density of σ ≥ 10 -10 S/ forms on the surface of the dielectric. In addition to his, the high concentration of the radiation-induced defects changes the optical and photoelectric properties of the materials and also the energy characteristics. Analysis of the photoelectric properties indicates that the recombination processes take part in electric transport. These processes restricted the increase of the photosensitivity and changing the kinetics of relaxation of photo conductivity (σ hv ). The practical application of the boron nitride (BN) the in the thermonuclear systems (for example, Ref. 7), stimulates research into the reasons for the deceleration of its properties under the effect of radiation of various types. The conductivity of non-irradiated boron nitride is of the electron-hole nature with a large fraction of the activation component in exchange of the charge carriers between the levels of the defects and the forbidden zones. On the basis of the correlation of the energy and kinetic parameters of luminescence and , the authors of Ref. 8 constructed a model of electron transfers accompanying the electric transport of the boron nitride. In addition to ion-thermal modification, the conductivity of boron nitride is also of the electron-hole nature and is accompanied by luminescence. Examination of the characteristics of luminescence may be useful for obtaining more information on the transport mechanism. In this work, in order to clarify the main parameters of the forbidden band, detailed investigations were carried out into the spectrum of the electronic states of radiation defects which determine the photoelectric and luminescence properties of the modified boron nitride. The

Contribution of inner shell Compton ionization to the X-ray fluorescence line intensity

Science.gov (United States)

Fernández, Jorge E.; Scot, Viviana; Di Giulio, Eugenio

2016-10-01

The Compton effect is a potential ionization mechanism of atoms. It produces vacancies in inner shells that are filled with the same mechanism of atomic relaxation as the one following photo-absorption. This contribution to X-ray fluorescence emission is frequently neglected because the total Compton cross-section is apparently much lower than the photoelectric one at useful X-ray energies. However, a more careful analysis suggests that is necessary to consider single shell cross sections (instead of total cross sections) as a function of energy. In this article these Compton cross sections are computed for the shells K, L1-L3 and M1-M5 in the framework of the impulse approximation. By comparing the Compton and the photoelectric cross-section for each shell it is then possible to determine the extent of the Compton correction to the intensity of the corresponding characteristic lines. It is shown that for the K shell the correction becomes relevant for excitation energies which are too high to be influent in X-ray spectrometry. In contrast, for L and M shells the Compton contribution is relevant for medium-Z elements and medium energies. To illustrate the different grades of relevance of the correction, for each ionized shell, the energies for which the Compton contribution reaches the extent levels of 1, 5, 10, 20, 50 and 100% of the photoelectric one are determined for all the elements with Z = 11-92. For practical applications it is provided a simple formula and fitting coefficients to compute average correction levels for the shells considered.

Nanographite-TiO2 photoanode for dye sensitized solar cells

Science.gov (United States)

Sharma, S. S.; Sharma, Khushboo; Sharma, Vinay

2016-05-01

Nanographite-TiO2 (NG-TiO2) composite was successfully synthesized by the hydrothermal method and its performance as the photoanode for dye-sensitized solar cells (DSSCs) was investigated. Environmental Scanning electron microscope (E-SEM) micrographs show the uniform distribution of TiO2 nanoflowers deposited over nanographite sheets. The average performance characteristics of the assembled cell in terms of short-ciruit current density (JSC), open circuit voltage (VOC), fill factor (FF) and photoelectric conversion efficiency (η) were measured.

Design of Portable Turbidimeter Based on Cygnal Microcomputer

International Nuclear Information System (INIS)

Sun, M J; Sun, X H; Zhou, J; Song, X C; Zhang, T; Zhang, X J

2006-01-01

Based on the characteristics of turbidity measurement, we have researched upon the portable light-scattering turbidity testing device by applying C8051F020. We try to simplify the circuit structure and improve the anti-interference of the device through the collection and process of data of the photoelectrical signal, as well as the control of circuit by C8051F020. Besides, the bubble disturbance inside light pathway is eliminated by means of mechanical agitating. Therefore the measurement is stablized

Photoelectric characteristics of an inverse U-shape buried doping design for crosstalk suppression in pinned photodiodes

International Nuclear Information System (INIS)

Cao Chen; Zhang Bing; Li Xin; Wu Longsheng; Wang Junfeng

2014-01-01

A design of an inverse U-shape buried doping in a pinned photodiode (PPD) of CMOS image sensors is proposed for electrical crosstalk suppression between adjacent pixels. The architecture achieves no extra fill factor consumption, and proper built-in electric fields can be established according to the doping gradient created by the injections of the extremely low P-type doping buried regions in the epitaxial layer, causing the excess electrons to easily drift back to the photosensitive area rarely with a diffusion probability; the overall junction capacitance and photosensitive area extensions for a full well capacity (FWC) and internal quantum efficiency (IQE) improving are achieved by the injection of a buried N-type doping. By considering the image lag issue, the process parameters of all the injections have been precisely optimized. Optical simulation results based on the finite difference time domain method show that compared to the conventional PPD, the electrical crosstalk rate of the proposed architecture can be decreased by 60%–80% at an incident wavelength beyond 450 nm, IQE can be clearly improved at an incident wavelength between 400 and 600 nm, and the FWC can be enhanced by 107.5%. Furthermore, the image lag performance is sustained to a perfect low level. The present study provides important guidance on the design of ultra high resolution image sensors. (semiconductor devices)

Synthesis and Characterization of a Gel-Type Electrolyte with Ionic Liquid Added for Dye-Sensitized Solar Cells

Directory of Open Access Journals (Sweden)

Le-Yan Shi

2013-01-01

Full Text Available This study intends to develop the electrolyte needed in dye-sensitized solar cells (DSSCs. Moreover, three different ionic liquids in different molalities are added to the gel-type electrolyte. Experimental results show that the DSSC composed of the gel-type electrolyte with no ionic liquid added can acquire 4.13% photoelectric conversion efficiency. However, the DSSC composed of the gel-type electrolyte with 0.4 M of 1-butyl-3-methylimidazolium chloride added has an open-circuit voltage of 810 mV, a short-circuit current density of 9.56 mA/cm2, and photoelectric conversion efficiency reaching 4.89%. Comparing this DSSC with the DSSC with no ionic liquid added, the photoelectric conversion efficiency can be enhanced by 18.4%. As to durability, the DSSC composed of the gel-type electrolyte with ionic liquid added still has a photoelectric conversion efficiency of 3.28% on the 7th day after it is stored in an enclosed space and maintains 0.72% efficiency on the 14th day. When the proposed DSSC is compared with the DSSC prepared by using a liquid-type electrolyte, the durability of its photoelectric conversion efficiency can be increased by 7 times.

Process and device for determining the spatial distribution of a radioactive substance

International Nuclear Information System (INIS)

1977-01-01

This invention describes a process for determining the spatial distribution of a radioactive substance consisting in determining the positions and energy losses associated to the interactions of the Compton effect and the photoelectric interactions that occur owing to the emission of gamma photons by the radioactive material and in deducing an information on the spatial distribution of the radioactive substance, depending on the positions and energy losses associated to the interactions of the Compton effect of these gamma photons and the positions and energy losses associated to the subsequent photoelectric interactions of these same photons. The invention also concerns a processing system for identifying, among the signals representing the positions and energy losses of the interactions of the Compton effect and the photoelectric interactions of the gamma photons emitted by a radioactive source, those signals that are in keeping with the gamma photons that have been subjected to an initial interaction of the Compton effect and a second and last photoelectric interaction. It further concerns a system for determining, among the identified signals, the positions of the sources of several gamma photons. This detector of Compton interaction can be used with conventional Auger-type imaging system (gamma camera) for detecting photoelectric interactions [fr

Effects of TiO2 film thickness on photovoltaic properties of dye-sensitized solar cell and its enhanced performance by graphene combination

International Nuclear Information System (INIS)

Zhang, Haiyan; Wang, Wenguang; Liu, Hui; Wang, Rong; Chen, Yiming; Wang, Zhiwei

2014-01-01

Graphical abstract: - Highlights: • DSSC based on TiO 2 film with 8 printing layers showed the highest efficiency. • The photoelectric conversion efficiency of the DSSC increased from 5.52% to 6.49% by graphene combination. • A mechanism for the enhanced performance of the DSSC was proposed. - Abstract: Dye-sensitized solar cells based on TiO 2 films with different printing layers (6-10) were fabricated by screen printing method. The prepared samples were characterized by scanning electron microscopy, X-ray diffraction and UV–vis absorption spectroscopy. The effects of thickness on the photoelectric conversion performance of the as-fabricated DSSCs were investigated. An optimum photoelectric conversion efficiency of 5.52% was obtained in a DSSC with 8 printing layers. Furthermore, after a moderate amount of graphene was combined with TiO 2 , the photoelectric conversion efficiency of the DSSC based on graphene/TiO 2 composite film rose from 5.52% to 6.49%, with an increase of η by 17.6%. The results indicated that graphene not only enhances the transport of electrons from the film to the fluorine doped tin oxide substrates and reduces the charge recombination rate, but also reduces the electrolyte–electrode interfacial resistance, clearly increasing the photoelectric conversion efficiency

Effects of TiO{sub 2} film thickness on photovoltaic properties of dye-sensitized solar cell and its enhanced performance by graphene combination

Energy Technology Data Exchange (ETDEWEB)

Zhang, Haiyan, E-mail: hyzhang@gdut.edu.cn [School of Materials and Energy, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100#, Guangzhou 510006 (China); Wang, Wenguang; Liu, Hui; Wang, Rong; Chen, Yiming [School of Materials and Energy, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100#, Guangzhou 510006 (China); Wang, Zhiwei [Anhui Key Laboratory of Nanomaterials and Nanostructures Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)

2014-01-01

Graphical abstract: - Highlights: • DSSC based on TiO{sub 2} film with 8 printing layers showed the highest efficiency. • The photoelectric conversion efficiency of the DSSC increased from 5.52% to 6.49% by graphene combination. • A mechanism for the enhanced performance of the DSSC was proposed. - Abstract: Dye-sensitized solar cells based on TiO{sub 2} films with different printing layers (6-10) were fabricated by screen printing method. The prepared samples were characterized by scanning electron microscopy, X-ray diffraction and UV–vis absorption spectroscopy. The effects of thickness on the photoelectric conversion performance of the as-fabricated DSSCs were investigated. An optimum photoelectric conversion efficiency of 5.52% was obtained in a DSSC with 8 printing layers. Furthermore, after a moderate amount of graphene was combined with TiO{sub 2}, the photoelectric conversion efficiency of the DSSC based on graphene/TiO{sub 2} composite film rose from 5.52% to 6.49%, with an increase of η by 17.6%. The results indicated that graphene not only enhances the transport of electrons from the film to the fluorine doped tin oxide substrates and reduces the charge recombination rate, but also reduces the electrolyte–electrode interfacial resistance, clearly increasing the photoelectric conversion efficiency.

Characteristics of liver tissue for attenuate the gamma radiation

International Nuclear Information System (INIS)

Arcos P, A.; Rodriguez N, S.; Pinedo S, A.; Amador V, P.; Chacon R, A.; Vega C, H.R.

2005-01-01

It was determined the lineal attenuation coefficient of hepatic tissue before gamma radiation of a source of 137 Cs. When exposing organic material before X or gamma radiation fields, part of the energy of the photons is absorbed by the material, while another part crosses it without producing any effect. The quantity of energy that is absorbed is a measure of the dose that receives the material. The three main mechanisms by means of which the gamma rays interacting with the matter are: The Photoelectric Effect, the Compton dispersion and the Even production; the sum of these three processes is translated in the attenuation coefficient of the radiation. In this work we have used hepatic tissue of bovine, as substitute of the human hepatic tissue, and we have measured the lineal attenuation coefficient for photons of 0.662 MeV. Through a series of calculations we have determined the lineal attenuation coefficient for photons from 10 -3 to 10 -5 MeV and the measured coefficient was compared with the one calculated. (Author)

Semiconductor particle mediated photoelectron transfers in bilayer lipid membranes

International Nuclear Information System (INIS)

Fendler, J.H.; Baral, S.

1989-01-01

This paper discusses semiconductor particles in situ generated on the cis surface of glyceryl monooleate (GMO) bilayer lipid membranes (BLMs), that have been used to mediate photoelectric effects. The presence of semiconductors on the BLM surface is addressed. The observed photoelectric effects are rationalized and presented

Sensitivity of photodiode detector for industrial computed tomography

International Nuclear Information System (INIS)

Wang Jue; Chen Jiaoze; Chen Xufeng; Tan Hui

2012-01-01

Studying on sensitivity of detector has most guiding significance for the selecting of X-ray Energy, the designing of detector and matching between X-ray source and detector. Several major factors of sensitivity and their quantitative relation were studied. First, factors such as energy deposition rate, absolute scintillation efficiency, light collection efficiency and photoelectrical conversion efficiency were analyzed. Then, a simulation for energy deposition rate of scintillation crystal and light collection efficiency was carried out by Monte Carlo method. The fluorescence conversion efficiency of the CsI (Tl) scintillator and the photoelectric conversion efficiency of the photoelectric diode were computed. The concept of matching between the scintillator and the photoelectric diode was defined. Finally, the sensitivity expression with universal meaning of the detector was obtained. The maximum error between theoretical value and practical measurement result is less than 20.4%. The experiments show the validity and the accuracy of the computing method of the sensitivity. (authors)

Nanographite-TiO_2 photoanode for dye sensitized solar cells

International Nuclear Information System (INIS)

Sharma, S. S.; Sharma, Khushboo; Sharma, Vinay

2016-01-01

Nanographite-TiO_2 (NG-TiO_2) composite was successfully synthesized by the hydrothermal method and its performance as the photoanode for dye-sensitized solar cells (DSSCs) was investigated. Environmental Scanning electron microscope (E-SEM) micrographs show the uniform distribution of TiO_2 nanoflowers deposited over nanographite sheets. The average performance characteristics of the assembled cell in terms of short-ciruit current density (J_S_C), open circuit voltage (V_O_C), fill factor (FF) and photoelectric conversion efficiency (η) were measured.

Electron-photon shower distribution function tables for lead, copper and air absorbers

CERN Document Server

Messel, H

2013-01-01

Electron-Photon Shower Distribution Function: Tables for Lead, Copper and Air Absorbers presents numerical results of the electron-photon shower distribution function for lead, copper, and air absorbers. Electron or photon interactions, including Compton scattering, elastic Coulomb scattering, and the photo-electric effect, are taken into account in the calculations. This book consists of four chapters and begins with a review of both theoretical and experimental work aimed at deducing the characteristics of the cascade produced from the propagation of high energy electrons and photons through

Photoelectric Properties of DSSCs Sensitized by Phloxine B and Bromophenol Blue

Directory of Open Access Journals (Sweden)

Penghui Ren

2016-01-01

Full Text Available Phloxine B and bromophenol blue as the sensitizers of dye-sensitized solar cells were investigated via UV-Vis spectra, FT-IR spectra, fluorescence spectra, and current-voltage characteristics. The frontier molecular orbital, vibration analysis, and the first hyperpolarizability were calculated with DFT/6-31G(d. The dipole moment, light harvesting efficiency (LHE, and larger absolute value of driving force of electron injection (ΔGinject were also discussed. The calculated results were compared with the experimental results of phloxine B and bromophenol blue. It was found that, compared with bromophenol blue, bigger dipole moment of phloxine B results in larger open circuit voltage (Voc according to the correlation between dipole moment and Voc. At the same time, for configuration of phloxine B, it has higher LHE and ΔGinject, which are helpful to enhance the abilities of absorbing sunlight and electron injection. Therefore, higher LHE and ΔGinject for phloxine B produced a larger value of Jsc.

Photoactive devices including porphyrinoids with coordinating additives

Science.gov (United States)

Forrest, Stephen R; Zimmerman, Jeramy; Yu, Eric K; Thompson, Mark E; Trinh, Cong; Whited, Matthew; Diev, Vlacheslav

2015-05-12

Coordinating additives are included in porphyrinoid-based materials to promote intermolecular organization and improve one or more photoelectric characteristics of the materials. The coordinating additives are selected from fullerene compounds and organic compounds having free electron pairs. Combinations of different coordinating additives can be used to tailor the characteristic properties of such porphyrinoid-based materials, including porphyrin oligomers. Bidentate ligands are one type of coordinating additive that can form coordination bonds with a central metal ion of two different porphyrinoid compounds to promote porphyrinoid alignment and/or pi-stacking. The coordinating additives can shift the absorption spectrum of a photoactive material toward higher wavelengths, increase the external quantum efficiency of the material, or both.

Fabrication of p-n heterostructure ZnO/Si moth-eye structures: Antireflection, enhanced charge separation and photocatalytic properties

Science.gov (United States)

Zeng, Yu; Chen, XiFang; Yi, Zao; Yi, Yougen; Xu, Xibin

2018-05-01

The pyramidal silicon substrate is formed by wet etching, then ZnO nanorods are grown on the surface of the pyramidal microstructure by a hydrothermal method to form a moth-eye composite heterostructure. The composite heterostructure of this material determines its excellent anti-reflection properties and ability to absorb light from all angles. In addition, due to the effective heterojunction binding area, the composite micro/nano structure has excellent photoelectric conversion performance. Its surface structure and the large specific surface area gives the material super hydrophilicity, excellent gas sensing characteristic, and photocatalytic properties. Based on the above characteristics, the micro/nano heterostructure can be used in solar cells, sensors, light-emitting devices, and photocatalytic fields.

Fabrication and characterization of photosensitive n-ZnO/p-InSe heterojunctions

Energy Technology Data Exchange (ETDEWEB)

Kudrynskyi, Z., E-mail: kudrynskyi@gmail.com [Frantsevich Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, Chernivtsi Branch, Str. I. Vilde 5, 58001 Chernivtsi (Ukraine); Khomyak, V. [Yuriy Fedkovich Chernivtsi National University, Str. Kotsubinsky 2, 58012 Chernivtsi (Ukraine); Katerynchuk, V.; Kovalyuk, M.; Netyaga, V.; Kushnir, B. [Frantsevich Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, Chernivtsi Branch, Str. I. Vilde 5, 58001 Chernivtsi (Ukraine)

2015-05-01

Indium monochalcogenide (InSe) with a band gap of 1.25 eV is a promising material for photovoltaic applications. In this work, photosensitive anisotype n-ZnO/p-InSe heterojunctions were fabricated by means of radio-frequency magnetron sputtering of the zinc oxide onto freshly cleaved (0001) van der Waals surface of p-InSe single-crystal. Structural properties of the obtained heterostructures were investigated by means of X-ray diffraction. Surface morphology of the grown ZnO thin films was studied by means of atomic force microscopy. The electrical and photoelectrical properties of the heterojunctions were investigated using the current-voltage characteristics measured at different temperatures, capacitance-voltage characteristics and photoresponse spectra. The dominating current transport mechanisms through the heterojunctions under investigation were determined at forward and reverse biases. It was found that the developed heterojunctions n-ZnO/p-InSe show photosensitivity in the photon energy range (1.25-3.20 eV) at room temperature. In addition, we analyzed the influence of vacuum annealing of the heterojunctions at different temperatures on their photoelectric properties. - Highlights: • Thin ZnO films were grown onto van der Waals surface of InSe substrate. • n-ZnO/p-InSe heterojunctions were fabricated. • The heterojunctions are photosensitive in photon energy range from 1.12 to 3.75 eV. • Despite the lattice mismatch of 19% the heterojunctions exhibit diode-like behavior. • Vacuum annealing improves electrical properties of the heterojunctions.

Thermoelectrical-electrothermal feedback (te-et f) enhanced performance characteristics of a high temperature superconductor far-infrared bolometer

International Nuclear Information System (INIS)

Kaila, M.M.; Russell, G.J.

2000-01-01

, aside from the normal heat transfer to the thermally conducting substrate. This is a further enhancement of the electrothermal feedback, strategic to the best performance of a photo-electrical bolometer. In this paper we carry out theoretical analysis, starting from the fundamental heat balance equation of the bolometer. Important computational results of the performance characteristics of the new composite bolometer are presented. It is demonstrated that this bolometer requires films in the micron thickness range. The temperature of operation is in the 80-120 K range, depending upon the choice of HTSC material. The bolometer is stable, as it is the temperature difference between hot and cold junctions rather than the absolute temperature of the bolometer that drives the bolometer. Responsivity of 100V / W, response time of ms and noise equivalent power of 1x10 -11 W are a technological reality without the requirement of mK temperatures

Laboratory Measurements of Optical and Physical Properties of Individual Lunar Dust Grains

Science.gov (United States)

Abbas, M. M.; Tankosic, D.; Craven, P. D.; Hoover, R. B.

2006-01-01

The lunar surface is covered with a thick layer of sub-micron/micron size dust grains formed by meteoritic impact over billions of years. The fine dust grains are levitated and transported on the lunar surface, and transient dust clouds over the lunar horizon were observed by experiments during the Apollo 17 mission. Theoretical models suggest that the dust grains on the lunar surface are charged by the solar UV radiation as well as the solar wind. Even without any physical activity, the dust grains are levitated by electrostatic fields and transported away from the surface in the near vacuum environment of the Moon. The current dust charging and levitation models, however, do not fully explain the observed phenomena. Since the abundance of dust on the Moon's surface with its observed adhesive characteristics has the potential of severe impact on human habitat and operations and lifetime of a variety of equipment, it is necessary to investigate the charging properties and the lunar dust phenomena in order to develop appropriate mitigating strategies. Photoelectric emission induced by the solar UV radiation with photon energies higher than the work function of the grain materials is recognized to be the dominant process for charging of the lunar dust, and requires measurements of the photoelectric yields to determine the charging and equilibrium potentials of individual dust grains. In this paper, we present the first laboratory measurements of the photoelectric yields of individual sub-micron/micron size dust grains selected from sample returns of Apollo 17, and Luna 24 missions, as well as similar size dust grains from the JSC-1 simulants. The experimental results were obtained on a laboratory facility based on an electrodynamic balance that permits a variety of experiments to be conducted on individual sub-micron/micron size dust grains in simulated space environments. The photoelectric emission measurements indicate grain size dependence with the yield

Optical timing receiver for the NASA Spaceborne Ranging System. Part II: high precision event-timing digitizer

Energy Technology Data Exchange (ETDEWEB)

Leskovar, Branko; Turko, Bojan

1978-08-01

Position-resolution capabilities of the NASA Spaceborne Laser Ranging System are essentially determined by the timeresolution capabilities of its optical timing receiver. The optical timing receiver consists of a fast photoelectric device; (e.g., photomultiplier or an avalanche photodiode detector), a timing discriminator, a high-precision event-timing digitizer, and a signal-processing system. The time-resolution capabilities of the receiver are determined by the photoelectron time spread of the photoelectric device, the time walk and resolution characteristics of the timing discriminator, and the resolution of the event-timing digitizer. It is thus necessary to evaluate available fast photoelectronic devices with respect to the time-resolution capabilities, and to develop a very low time walk timing discriminator and a high-resolution event-timing digitizer to be used in the high-resolution spaceborne laser ranging system receiver. This part of the report describes the development of a high precision event-timing digitizer. The event-timing digitizer is basically a combination of a very accurate high resolution real time digital clock and an interval timer. The timing digitizer is a high resolution multiple stop clock, counting the time up to 131 days in 19.5 ps increments.

Modeling of the photodetector based on the multilayer graphene nanoribbons

International Nuclear Information System (INIS)

Liu, Haiyue; Niu, Yanxiong; Yin, Yiheng; Liu, Shuai

2016-01-01

Graphene nanoribbon (GNR), which has unique properties and advantages, is a crucial component of nanoelectornic devices, especially in the development of photoelectric detectors. In this work, an infrared photodetector based on the structure of stacked multiple-GNRs, which is separated by a little thick barrier layers (made of tungsten disulfide or related materials) to prevent tunneling current, is proposed and modeled. Operation of photoelectric detector is related to the electron cascaded radiative transition in the adjacent GNRs strengthened by the electrons heated due to the incident light. With a developed model, the working principle is analyzed and the relationships for the photocurrent and dark current as functions of the intensity of the incident radiation are derived. The spectral dependence of the responsivity and detectivity for graphene nanoribbons photodetector (GNRs-PT) with different Fermi energy, band gaps and numbers of GNRs layers are analyzed as well. The results demonstrate that the spectral characteristics depend on the GNRs band gap, which shows a potential on GNRs-PT application in the multi-wavelength systems. In addition, GNRs-PT has a better spectrum property and higher responsivity compared to photodetectors based on In_xGa_xAs in room temperature.

Modeling of the photodetector based on the multilayer graphene nanoribbons

Energy Technology Data Exchange (ETDEWEB)

Liu, Haiyue [Department of Instrumentation Science and Opto-electronics Engineering, Beijing University of Aeronautics and Astronautics, Beijing, 100191 (China); Key Laboratory of Micro-nano Measurement-Manipulation and Physics Ministry of Education, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Niu, Yanxiong, E-mail: niuyx@buaa.edu.cn [Department of Instrumentation Science and Opto-electronics Engineering, Beijing University of Aeronautics and Astronautics, Beijing, 100191 (China); Key Laboratory of Micro-nano Measurement-Manipulation and Physics Ministry of Education, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Precision Opto-mechatronics Technology Key Laboratory of Education Ministry, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Yin, Yiheng [Department of Instrumentation Science and Opto-electronics Engineering, Beijing University of Aeronautics and Astronautics, Beijing, 100191 (China); Liu, Shuai [Department of Instrumentation Science and Opto-electronics Engineering, Beijing University of Aeronautics and Astronautics, Beijing, 100191 (China); Precision Opto-mechatronics Technology Key Laboratory of Education Ministry, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China)

2016-07-15

Graphene nanoribbon (GNR), which has unique properties and advantages, is a crucial component of nanoelectornic devices, especially in the development of photoelectric detectors. In this work, an infrared photodetector based on the structure of stacked multiple-GNRs, which is separated by a little thick barrier layers (made of tungsten disulfide or related materials) to prevent tunneling current, is proposed and modeled. Operation of photoelectric detector is related to the electron cascaded radiative transition in the adjacent GNRs strengthened by the electrons heated due to the incident light. With a developed model, the working principle is analyzed and the relationships for the photocurrent and dark current as functions of the intensity of the incident radiation are derived. The spectral dependence of the responsivity and detectivity for graphene nanoribbons photodetector (GNRs-PT) with different Fermi energy, band gaps and numbers of GNRs layers are analyzed as well. The results demonstrate that the spectral characteristics depend on the GNRs band gap, which shows a potential on GNRs-PT application in the multi-wavelength systems. In addition, GNRs-PT has a better spectrum property and higher responsivity compared to photodetectors based on In{sub x}Ga{sub x}As in room temperature.

Study of light collection uniformity dependence on reflector type in a large scintillation counter

International Nuclear Information System (INIS)

Astvatsaturov, R.G.; Ivanov, V.I.; Knapik, E.; Kramarenko, V.A.; Malakhov, A.I.; Khachaturyan, M.N.

1977-01-01

An investigation of the way to improve uniformity of light collection onto photoelectric multiplier photocathode, for the 100x10x2 cm scintillation counter, has been undertaken. Pulse amplitude versus the point, particles strike a scintillator, relationship, has been demonstrated for several types of reflectors. Used as reflectors were: white papar, aluminium foil, black papar and a combination of above reflectors. Experimental data analysis shows, that the combination of reflectors with different reflection coefficient, provides a means for 1,5 time improvement of counter light collection uniformity, with no impairment of amplitude characteristics

Microphysical and chemical characteristics of near-water aerosol over White and Kara Seas

Science.gov (United States)

Terpugova, S. A.; Polkin, V. V.; Panchenko, M. V.; Golobokova, L. P.; Kozlov, V. S.; Shmargunov, V. P.; Shevchenko, V. P.; Lisitzin, A. P.

2009-04-01

The results are presented of five-year-long (2003-2007) study of the spatial - temporal variability of the near-water aerosol in the water area of White and Kara Seas (55, 64, 71 and 80-th cruises of RV "Professor Shtockman"; 53 and 54-th cruises of RV "Akademik Mstislav Keldysh"). Measurements of aerosol microphysical characteristics were carried out by means of the automated mobile aerosol complex consisting of nephelometer, photoelectric counter and aethalometer. The aerosol disperse composition was studied with photoelectric counter in 256 size intervals from 0.4 to 10 m. About 1500 series of measurements were carried out in White Sea, and about 1400 series in Kara Sea. Chemical characteristics of aerosol were determined from samples collected on aerosol filters (92 samples were collected in White Sea and 48 in Kara Sea). The ion composition was determined under laboratory conditions. The H+, Na+, K+, Ca2+, Mg2+, NH4+, Cl-, NO3-, HCO3-, SO42- ions were under examination. Comparing aerosol characteristics of two seas, one can note that the mean values of the aerosol content parameters in Kara Sea are less than in White Sea. The ratio of the aerosol mass concentration are from 2 (Yamal Peninsula, northern part of Novaya Zemlya) to 9 times (Blagopoluchia Bay, Ob' Gulf). The differences in the concentration of black carbon vary from 3 (Yamal Peninsula) to 17 times (Blagopoluchia Bay). The differences in the aerosol number concentration NA are not so big. The values NA near Kara Gate, Yamal Peninsula and northern part of Novaya Zemlya are practically the same as in White Sea. The concentration NA at Ob' gulf is one order of magnitude less than in White sea. The obtained aerosol volume size distributions were approximated by the sums of two fractions, submicron and coarse, with lognormal size distributions. The mean volume size distribution of submicron fraction in White Sea is approximated by the distribution with the variance of the radius logarithm s=0.6 and modal

Bulk photovoltaic effect in photoconductive metamaterials based on cone-shaped nanoparticles

DEFF Research Database (Denmark)

Zhukovsky, Sergei; Babicheva, Viktoriia; Uskov, Alexander V.

2014-01-01

is the directanalogy of the photogalvanic effect known to exist in naturally occurring non-centrosymmetric media. This plasmonic bulk photovoltaic effect is intermediate between the inner photoelectric effect in bulk media and the outer photoelectric effect atmacroscopic interfaces. The results obtained are valuable...... for characterizing photoemission and photoconductive properties of plasmonic nanostructures. They can find many uses for photodetection-related and photovoltaic applications...

Laboratory Studies of the Optical Properties and Condensation Processes of Cosmic Dust Particles

Science.gov (United States)

Abbas, Mian M.; Craven, Paul D.; Spann, James F.; Tankosic, Dragana; Six, N. Frank (Technical Monitor)

2002-01-01

A laboratory facility for levitating single isolated dust particles in an electrodynamics balance has been developing at NASA/Marshall Space Flight Center for conducting a variety of experimental, of astrophysical interest. The objective of this research is to employ this innovative experimental technique for studies of the physical and optical properties of the analogs of cosmic grains of 0.2-10 micron size in a chamber with controlled pressure/temperatures simulating astrophysical environments. In particular, we will carry out three classes of experiments to investigate the microphysics of the analogs of interstellar and interplanetary dust grains. (1) Charge characteristics of micron size single dust grains to determine the photoelectric efficiencies, yields, and equilibrium potentials when exposed to UV radiation. These measurements will provide the much-needed photoelectric emission data relating to individual particles as opposed to that for the bulk materials available so far. (2) Infrared optical properties of dust particles obtained by irradiating the particles with radiation from tunable infrared diode lasers and measuring the scattered radiation. Specifically, the complex refractive indices, the extinction coefficients, the scattering phase functions, and the polarization properties of single dust grains of interest in interstellar environments, in the 1-25 micron spectral region will be determined. (3) Condensation experiments to investigate the deposition of volatile gases on colder nucleated particles in dense interstellar clouds and lower planetary atmospheres. The increase in the mass or m/q ratio due to condensation on the particle will be monitored as a function of the dust particle temperature and the partial pressure of the injected volatile gas. The measured data wild permit determination of the sticking efficiencies of volatile gases of astrophysical interest. Preliminary results based on photoelectric emission experiments on 0.2-6.6 micron

Phototelectric Emission Measurements on the Analogs of Individual Cosmic Dust Grains

Science.gov (United States)

Abbas, Mian M.; Tankosic, D.; Craven, P. D.; Spann, J. F.; LeClair, A.; West, E. A.; Weingartner, J. C.; Tielens, A. G. G. M.; Nuth, J. A.; Camata, R. P.;

Temperature radiation measuring equipment. Temperaturstrahlungsmessgeraet

Energy Technology Data Exchange (ETDEWEB)

Lotzer, W

1981-01-22

The invention is concerned with a temperature radiation measuring equipment for non-contact temperature measurement by the light intensity variation method, with a photoelectric resistance as the measuring element. By having a circuit with a transistor, the 'dark resistance' occurring in the course of time is compensated for and thus gives a genuine reading (ie. the voltage drop across the photoelectric resistance remains constant).

基于红外光电传感器的智能寻迹小车设计%Design of intelligent-searching-track race car based on infrared photoelectric sensor

Institute of Scientific and Technical Information of China (English)

胡媛媛; 邓世建; 王书婧

2011-01-01

寻迹小车可以看作是缩小化的智能汽车,对智能汽车的研究有一定的借鉴意义.采用飞思卡尔公司的MC9S12DG128B作为核心控制芯片,设计了通过红外光电传惠器检测路径信息的智能寻迹小车.该系统由处理器模块、路径识别模块、电机驱动模块、舵机驱动模块、车速检测模块、液晶显示模块与电源模块等组成.实际应用表明,该小车可以在专门设计的跑道上快速平稳地实现寻迹功能.%The tracing car can be regarded as the contractible intelligent vehicle. Its research has a certain significance for the intelligent car. By using Freescale company's devices MC9S12DG128B as the core control chip, this paper designed the intelligent tracing car to detection route information through the infrared photoelectric sensor. The system includes processor module, path recognition module, motor driver module, servo driver module, speed detection module, LCD module,power supply module and so on. The practical application shows that the car can rapidly and smoothly realize the tracing function in the runway of the special design.

ANALISIS PERPUTARAN RADIASI SURYA TERHADAP KINERJA SEL FOTOLISTRIK SEBAGAI ENERGI RAMAH LINGKUNGAN DI NUSA PENIDA KABUPATEN KLUNGKUNG PROVINSI BALI

Directory of Open Access Journals (Sweden)

I N. Suastaka

2015-08-01

Full Text Available Photoelectric cells is an equipment made of semiconductor material of Silicone (Si14 functioned to catchand converse sun light to become electric energy directly. Through photoelectric phenomenon, that sun lightas particles with frequency/wavelength of certain light can release electrons in a material. This electrons’movement can produce electric current. The aim of this research was to find out the performance of aphotoelectric cells collector in conversing sun light to become electric energy due to the rotation of solarradiation in Nusa Penida.The research was conducted at PLTS electric home solar system Nusa Penida for 5 days the measurementto the parameter of Current (Isc and Voltage (Vsc. Each measurement had duration of lighting for 8 hourseach from 09.00 until 16.00 Central Indonesian Time, with time interval of 30 minutes. Measurement anddata analysis produced in the research on Saturday, June 29th 2013 obtained: the amount of solar radiationarrived at earth’s outer atmosphere was 1321.90 W/m2, and passed along to earth’s surface at 621.29 W/m2,and received by photoelectric cells collector as heat power at 113.63 Watt, and efficiency produced was 25.3%,and electric power produced was 28.74 Watt, and can be equalized with fossil energy of 0.0237 liter ofgasoline, or equivalent to 106.65 rupiah. It meant that, photoelectric cells collector with area of 50 x 110cm2in a day can protect earth from global warming of 28.74 Watt, in using of fossil energy at 0.0237 liter ofgasoline.The efficient performance of photoelectric cells was still considered small. In order to achieve big capacityof electric power required a lot of collector modules and large area, so that with the growing of semiconductortechnology, it is expected that whenever possible it can reduce electron binding energy on material, andoptimize solar lighting system to photoelectric cells collector modules, so that the efficient performance ofphotoelectric cells can be

Determination of Atomic Number Exponent for Elemental Absorber at Am-241 Energy in X-Ray Attenuation Experiments

International Nuclear Information System (INIS)

Najim, L.A.; Shamoon, S.K.; Atalah, S.T.

2012-01-01

In X-ray absorption experiment, the dependence of the photoelectric absorption cross-section varied with atomic number Z.In this paper, the dependence on Z of the cross-section or coefficient of photoelectric absorption is first evaluated from published data for (20) elements ranging from Al-Sn, and then the cross-section for Fe is obtained experimentally by measuring the X-ray intensity with and without the Fe absorber and compared with the theoretical value, the variation of the photoelectric absorption coefficient (μ/ρ m ) showed less dependence on Z for the two tested of Z regions.This is because of the inclusion of mass density (ρ m ) of the absorber in the coefficient.The values of m obtained in the present work increases linearly with energy for both ranges of elements

Heterojunctions of oxide-p-InSe on oriented (110) crystal substrate

CERN Document Server

Katerinchuk, V N; Betsa, T V; Kaminskij, V M; Netyaga, V V

2001-01-01

The photoelectric properties of the oxide-p-InSe heterotransition, formed in the plane, parallel to the C crystallographic axis, are studied. The heterotransitions are formed through the thermal oxidation of the InSe crystalline sublattice. The influence of the surface recombination effects on the heterotransition properties is not determined. It is established from the volt-farad characteristics, that the p-n-transition type is sharp, and the energy barrier value constitutes 0.17 V. It is determined also, that the current flow through the heterotransition barrier is described within the frames of the diode theory

The system of quantum structures coated with the diamond-like carbon for silicon solar cells

International Nuclear Information System (INIS)

Efimov, V.P.; Abyzov, A.S.; Luchaninov, A.A.; Omarov, A.O.; Strel'nitskij, V.E.

2010-01-01

The peculiarity of the process of amorphous diamond-like carbon coating deposition on the surface of Si photoelectric cell with quantum filaments, which was irradiated by the electrons and heavy multi-charge ions, have been investigated. The experimental results on the investigations of the optical characteristics of the nitrogen doped hydrogenated diamond-like carbon a-C:(H,N) coatings were presented. The parameters of the process of a-C:(H,N) coating deposition on the surfaces of disordered Si semiconductors structures were optimized for the purpose of minimizing optical reflection coefficient from the front surface of the crystal and supplying its mechanical durability.

X-ray and UV spectroscopy of Cygnus X-1 = HDE226868

Science.gov (United States)

Pravdo, S. H.; White, N. E.; Kondo, Y.; Becker, R. H.; Boldt, E. A.; Holt, S. S.; Serlemitsos, P. J.; Mccluskey, B. G.

1980-01-01

Observations are presented of Cygnus X-1 with the solid-state spectrometer on the Einstein Observatory. The X-ray spectra of two intensity dips viewed near superior conjunction did not exhibit increased photoelectric absorption. Rather the data support a model in which an increase in the electron scattering optical depth modifies both the observed spectrum and the intensity. The characteristic temperature of the intervening material is greater than 5 x 10 to the 7th power K. These measurements were in part simultaneous with observations by IUE. The ultra violet spectrum and intensity remained relatively constant during an X-ray intensity dip.

γ-irradiation effect on electronic properties in hydrogenated amorphous silicon

International Nuclear Information System (INIS)

Shirafuji, J.; Nagata, S.; Shirakawa, K.

1986-01-01

γ-irradiation effect on electron transport and photoelectric properties in glow-discharge hydrogenated amorphous silicon is investigated mainly by means of time-of-flight measurement. Although the electron transport changes from non-dispersive to dispersive when the total dose on γ-rays is increased, the electron mobility at room temperature is affected only slightly by γ-irradiation. The γ-irradiation introduces dominantly Si dangling bonds, allowing to study the recombination characteristic as a function of dangling bond density under controllable conditions. It is found that the electron recombination lifetime is inversely proportional to the dangling bond density. (author)

The Application Study in Solar Energy Technology for Highway Service Area: A Case Study of West Lushan Highway Low-Carbon Service Area in China

Directory of Open Access Journals (Sweden)

Xiaochun Qin

2015-01-01

Full Text Available A lot of research works have been made concerning highway service area or solar technology and acquired great achievements. However, unfortunately, few works have been made combining the two topics together of highway service areas and solar energy saving to make a systemic research on solar technology application for highway service area. In this paper, taking West Lushan highway low-carbon service area in Jiangxi Province of China as the case study, the advantages, technical principles, and application methods of solar energy technology for highway service area including solar photoelectric technology and solar water heating technology were discussed based on the analysis of characteristics of highway low-carbon service area; the system types, operation mode, and installing tilt angle of the two kinds of solar systems suitable for highway service areas were confirmed. It was proved that the reduction of the cost by electricity savings of solar system was huge. Taking the investment of the solar systems into account, the payback period of solar photoelectric systems and solar water heating systems was calculated. The economic effect of the solar systems in West Lushan highway service area during the effective operation periods was also calculated and proved very considerable.

The effect of the geometry on the fluorescence radiation field

International Nuclear Information System (INIS)

Teodori, F.; Fernandez, J.E.; Molinari, V.

2000-01-01

In x-ray fluorescence spectroscopy a narrow photon beam is focused on the surface of the sample to stimulate the production of characteristic radiation which gives useful information about the composition of the target. Even if the interpretation of the measurement is simple, the quantification of the total emitted intensity is not straightforward because the primary photons are produced in the depth of the sample and only a fraction can reach the surface without colliding again with matter. In this work we show that the geometry of the system plays an important role in determining the properties of the 3D radiation field. By using the integral Boltzmann equation, we show that there exist a link among the source distribution, the boundary conditions, the emission points, the observation angles and the properties of the field of emitted radiation. To illustrate the influence of the geometry, the energy distribution of a continuos emission spectrum like the Compton one has been calculated, firstly. It is shown that the energy distribution of the Compton primary photons (coming out from a slab irradiated with an internal monochromatic and isotropic point source) changes with the orientation of the observation direction. Another example involves a second order effect which depends on a double collision in the specimen. It has been shown that the characteristic emission due to the photoelectric effect is accompanied by a (P,C) continuous contribution which introduces an asymmetry in the shape of the line. Computations in a 3D radiation field have shown that such asymmetry is strongly dependent on the observation direction with respect to the primary volume where the photoelectric effect is produced. This means that detection through a narrow collimator whose axis (assumed here as the observation direction) deviates from the centre of symmetry of the primary volume, will produce differently shaped characteristic lines depending on the extent and placement of the

Photoelectric charging of dust grains

International Nuclear Information System (INIS)

Ignatov, A. M.

2009-01-01

Photoemission from the surface of a dust grain in vacuum is considered. It is shown that the cutoff in the energy spectrum of emitted electrons leads to the formation of a steady-state electron cloud. The equation describing the distribution of the electric potential in the vicinity of a dust grain is solved numerically. The dust grain charge is found as a function of the grain size.

Hard X-ray Photoelectric Polarimeter

Data.gov (United States)

National Aeronautics and Space Administration — Our objective is to determine the gas mixtures and pressures that would enable a sensitive, hard X-ray polarimeter using existing flight components with the goal of...

Photoelectric observations of CH Cygni

Energy Technology Data Exchange (ETDEWEB)

Luud, L; Ruusalepp, M; Vennik, Ya

1977-01-01

UBV observations of the peculiar variable star CH Cygni from 1968 up to 1974 are presented. HD 182691 served as a comparison star. It turned out that the colours are in accordance with a model for a symbiotic star. The colour-magnitude diagrams of CH Cygni allow dividing the period of the observations into two parts in dependence on the activity of CH Cygni. Observed brightness variations are analyzed by using autocorrelation, crosscorrelation, and power spectral density functions. It has been found that brightness variations have some periods which are given.

Giacobini-Zinner comet: polarimetric and physical observations

International Nuclear Information System (INIS)

Martel, M.T.; Maines, P.; Grudzinska, S.; Stawikowski, A.

1984-10-01

The results of observations of the Giacobini-Zinner comet on 25 and 31 October 1959 are presented. The magnitude of the comet was measured photoelectrically in two spectral regions. The radius is on the order of one kilometer. The photoelectric measurements of comets 1959b and 1957c were used to measure the abundances of the CN and C2 radicals and of solid particles in the heads

A novel π–conjugated Zn⟵S→Zn unit interface in the ZnS/Zn(S){sub 2}L inorganic/orgainc hybrids for significant photoelectric response

Energy Technology Data Exchange (ETDEWEB)

Gao, Yuanhao, E-mail: gyh-2007@sohu.com [Key Laboratory of Micro–Nano Materials for Energy Storage and Conversion of Henan Province and Institute of Surface Micro and Nano Materials, Xuchang University, Xuchang 461000 (China); Zhang, Xiaofei; Wang, Peipei [College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450000 (China); Lei, Yan, E-mail: leiyan361@163.com [Key Laboratory of Micro–Nano Materials for Energy Storage and Conversion of Henan Province and Institute of Surface Micro and Nano Materials, Xuchang University, Xuchang 461000 (China); Yang, Xiaognag; Fa, Wenjun [Key Laboratory of Micro–Nano Materials for Energy Storage and Conversion of Henan Province and Institute of Surface Micro and Nano Materials, Xuchang University, Xuchang 461000 (China); Niu, Helin [Department of Chemistry, Anhui University, Hefei 230039 (China); Zheng, Zhi [Key Laboratory of Micro–Nano Materials for Energy Storage and Conversion of Henan Province and Institute of Surface Micro and Nano Materials, Xuchang University, Xuchang 461000 (China)

2017-04-30

Highlights: • ZnS/Zn(S){sub 2}L is synthesized by using ZnS nanocrystals and Zn(S){sub 2}L complex. • There is a novel Zn⟵S→Zn unit interface in ZnS/Zn(S){sub 2}L hybrid system. • Luminescence quantum efficiency of ZnS/Zn(S){sub 2}L is up to 69%. • The π–conjugated Zn⟵S→Zn bridge enhanced the electron transfer effectively. - Abstract: By using a novel Zn(S){sub 2}L complex (L = N–hexyl–3–{2–(4–(2,2′:6′,2′′–terpyridin–4′–yl)phenyl)ethenyl}carbazole) as a surface stabilizing agent, the self–assembled microspheres of Zn(S){sub 2}L–capped ZnS nanocrystals are obtained in a simple ethanol solvothermal process. Because of the strong π character of the two terminal sulfur atoms (S{sup 1–} valence state) in the Zn(S){sub 2}L complex, the Zn(S){sub 2}L complex could incorporate ZnS nanocrystals together by a homologous Zn⟵S→Zn unit interface. In the work, the homologous Zn⟵S→Zn unit interface is proposed to function as a π–conjugated bridge for effective electron–transfer transition from Zn(S){sub 2}L moiety to ZnS nanocrystal to significantly improve the photoelectric response performance, such as the long lifetime of photogenerated charge carriers from 8 × 10{sup −8} s to 4 × 10{sup −5} s and the high recombination luminescence quantum efficiency (QE) up to 69%, which are confirmed by the systematically investigation with Raman spectra, XPS spectra, Uv–vis absorption spectra, photoluminescence (PL) spectra and transient photovoltage (TPV) technique. The ZnS/Zn(S){sub 2}L used as extra electron donor in organic/inorganic hybrid solar cell device could increase performance up to about 30%.

Nuclear reactor and production systems with flux-optical digitizer

International Nuclear Information System (INIS)

Luger, P.P.; Nealen, J.P.

1979-01-01

Several digital sensing devices are described for use in automated production systems. The first described is for use in the automatic operation of a reactor. This device employs a binant electrometer using a quartz fiber mounted at one end but free to vibrate at the other in an AC field. The fiber oscillates if a charge is placed upon it. An optical slit replaces the ordinary eyepiece reticule scale. With the quartz fiber adjusted so its image is in focus at the optical slit, photoelectric signals are obtained at null charge on the fiber. The quartz fiber is repeatedly charged and allowed to discharge by collecting ions from a source under measurement. Each photoelectric signal causes a digital time reading to be taken. The time readings are used to evaluate the current due to the electric charge. The photoelectric signals, by feedback, also operate the electrometer for continuous intermittent-continuous operation. Basically the current is a current digitizer. Application is made to reactor monitoring and control as well as to other types of production systems. The flux-optical digitizer is a radiometer-like-structure carryig rotating fins that may be coated with fissionable material, such as 235 U for the purpose of neutron flux measurements. The rotating fins are mounted on a shaft that also carries an arm that produces photoelectric signals whenever the arm overlaps an optical slit and thus diminishes light from an auxiliary light flux source incident on the slit. Between successive photoelectric signals, time interval measurements are obtained. This and other sensing devices are fully described for various automated, controlled, production processes

Electron transport properties in ZnO nanowires/poly(3-hexylthiophene) hybrid nanostructure

International Nuclear Information System (INIS)

Cheng Ke; Cheng Gang; Wang Shujie; Fu Dongwei; Zou Bingsuo; Du Zuliang

2010-01-01

The ZnO nanowires (NWs) array/poly(3-hexylthiophene) (P3HT) hybrid prototype device was fabricated. An ultraviolet (UV) light of λ = 350 nm is used to investigate the photo-electric properties of the ZnO NWs array and hybrid structure. In this way, we can avoid the excitation of P3HT, which can give us a real electron transport ability of ZnO NWs itself. Our results demonstrated a higher and faster photo-electric response of 3 s for the hybrid structure while 9 s for the ZnO NWs array. The surface states related slow photo-electric response was also observed for them. The charge transfer mechanism and the influence of surface states were discussed. The current work provides us profound understandings on the electron transport ability of ZnO NWs array in a working hybrid polymer solar cell, which is crucial for optimizing the device performance.

Photodiode 1 × 64 linear array based on a double p-InAsSbP/n-InAs{sub 0.92}Sb{sub 0.08}/n{sup +}-InAs heterostructure

Energy Technology Data Exchange (ETDEWEB)

Il’inskaya, N. D., E-mail: ioffeled@mail.ru; Karandashev, S. A. [Russian Academy of Sciences, Ioffe Institute (Russian Federation); Karpukhina, N. G. [Limited Liability Company Ioffe LED Ltd. (Russian Federation); Lavrov, A. A.; Matveev, B. A.; Remennyi, M. A.; Stus, N. M.; Usikova, A. A. [Russian Academy of Sciences, Ioffe Institute (Russian Federation)

2016-05-15

The results of studies of the current–voltage characteristics and of the photoelectric and luminescence properties of a monolithic diode 1 × 64 linear array based on p-InAsSbP/n-InAsSb/n{sup +}-InAs with the n{sup +}-InAs-substrate side illuminated and sensitive in the region of 4-μm are reported. An analysis is performed of the mechanisms of current flow in the temperature range of 77–353 K and also of the photosensitivity and the speed of response taking into account the spatial distribution of nonequilibrium radiation and the data of capacitance–voltage measurements.

Individual SnO2 nanowire transistors fabricated by the gold microwire mask method

International Nuclear Information System (INIS)

Sun Jia; Tang Qingxin; Lu Aixia; Jiang Xuejiao; Wan Qing

2009-01-01

A gold microwire mask method is developed for the fabrication of transistors based on single lightly Sb-doped SnO 2 nanowires. Damage of the nanowire's surface can be avoided without any thermal annealing and surface modification, which is very convenient for the fundamental electrical and photoelectric characterization of one-dimensional inorganic nanomaterials. Transport measurements of the individual SnO 2 nanowire devices demonstrate the high-performance n-type field effect transistor characteristics without significant hysteresis in the transfer curves. The current on/off ratio and the subthreshold swing of the nanowire transistors are found to be 10 6 and 240 mV/decade, respectively.

Three-color photometry of HDE 226868: The optical counterpart of cygnus X-1

International Nuclear Information System (INIS)

Lester, D.F.; Nolt, I.G.; Stearns, S.A.; Straton, P.; Radostitz, J.V.

1976-01-01

The results of UBV photoelectric observations of HDE 226868 (Cyg X-1) obtained on fifty nights during 1974 are presented. These observations show a light curve with the following characteristics: two unequal light maxima and minima during the 5/sup d/.6 orbital period which exhibit a peak-to-peak magnitude change of approx.0.07 mag in all colors;a small phase-dependent color variation which results in a reddening in both color indices of approx.0.003 mag at times of light minima; erratic light variability on a general time scale of days with an amplitude of +- 0.01 to 0.02 mag and no apparent color dependence

Down-conversion emission of Ce3+-Tb3+ co-doped CaF2 hollow spheres and application for solar cells

Science.gov (United States)

Cheng, Yufei; Wang, Yongbo; Teng, Feng; Dong, Hua; Chen, Lida; Mu, Jianglong; Sun, Qian; Fan, Jun; Hu, Xiaoyun; Miao, Hui

2018-03-01

Luminescent downconversion is a promising way to harvest ultraviolet sunlight and transform it into visible light that can be absorbed by solar cells, and has potential to improve their photoelectric conversion efficiency. In this work, the uniform hollow spheres and well dispersed CaF2 phosphors doped with rare-earth Ce3+ and Tb3+ ions are prepared by a one-step hydrothermal synthesis method. Benefiting from the stronger ability of absorption and emission and excellent transparency property, we demonstrate that the application of the doped nanocrystals can efficiently improve visible light transmittance. The chosen phosphors are added in the SiO2 sols so as to get the anti-reflection coatings with wavelength conversion bi-functional films, promoting the optical transmittance in the visible and near-infrared range which matches with the range of the band gap energy of silicon semiconductor. Optimized photoelectric conversion efficiency of 14.35% and the external quantum efficiency over 70% from 450 to 950 nm are obtained through the silicon solar cells with 0.10 g phosphors coating. Compared with the pure glass devices, the photoelectric conversion efficiency is enhanced by 0.69%. This work indicates that fluorescent downconversion not only can serve as proof of principles for improving photoelectric conversion efficiency of solar cells but also may be helpful to practical application in the future.

CMOS-based optical energy harvesting circuit for biomedical and Internet of Things devices

Science.gov (United States)

Nattakarn, Wuthibenjaphonchai; Ishizu, Takaaki; Haruta, Makito; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Sawan, Mohamad; Ohta, Jun

2018-04-01

In this work, we present a novel CMOS-based optical energy harvesting technology for implantable and Internet of Things (IoT) devices. In the proposed system, a CMOS energy-harvesting circuit accumulates a small amount of photoelectrically converted energy in an external capacitor, and intermittently supplies this power to a target device. Two optical energy-harvesting circuit types were implemented and evaluated. Furthermore, we developed a photoelectrically powered optical identification (ID) circuit that is suitable for IoT technology applications.

Detailed tabulation of atomic form factors, photoelectric absorption and scattering cross section, and mass attenuation coefficients in the vicinity of absorption edges in the soft X-ray (Z=30-36, Z=60-89, E=0.1 keV-10 keV), addressing convergence issues of earlier work

International Nuclear Information System (INIS)

Chantler, C.T.

2000-01-01

Reliable knowledge of the complex x-ray form factor [Re(f ) ] and the photoelectric attenuation coefficient (σ PE ) is required for crystallography, medical diagnosis, radiation safety, and XAFS studies. Discrepancies between currently used theoretical approaches of 200% exist for numerous elements from 1 to 3 keV x-ray energies. The key discrepancies are due to the smoothing of edge structure, the use of nonrelativistic wave functions, and the lack of appropriate convergence of wave functions. This paper addresses these key discrepancies and derives new theoretical results of substantially higher accuracy in near-edge soft x-ray regions. The high-energy limitations of the current approach are also illustrated. The energy range covered is 0.1 to 10 keV. The associated figures and tabulation demonstrate the current comparison with alternate theory and with available experimental data. In general, experimental data are not sufficiently accurate to establish the errors and inadequacies of theory at this level. However, the best experimental data and the observed experimental structure as a function of energy are strong indicators of the validity of the current approach. New developments in experimental measurement hold great promise in making critical comparisons with theory in the near future

Achievement report for fiscal 1984 on Sunshine Program-entrusted research and development. Optical research on electronic state in amorphous silicon. (Research and development of amorphous solar cells); 1984 nendo amorphous silicon no denshi jotai no kogakuteki kenkyu seika hokokusho. Amorphous taiyo denchi no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1985-03-01

For realizing a high-performance amorphous solar cell, research is conducted on how to evaluate the amorphous silicon film formed by glow discharge decomposition as regards its optical and photoelectric characteristics, basic physical properties of its electronic states, and its film quality and film forming conditions. Research is conducted on the mechanism of glow discharge decomposition reaction using plasma spectroscopic techniques and on the conditions of film formation, when low-temperature SiO{sub 2} film growth is caused to occur by a directly excited photo-CVD (chemical vapor deposition) method in which a deuterium lamp and Xe lamp are the exciting light sources and SiH{sub 4} and O{sub 2} are the source gases. In research on the mechanism of photoelectric conversion in an a-Si film p-I-n junction system, a method is developed of evaluating physical property parameters in accordance with a field drift type photovoltaic effect model. In research on the evaluation of the optical properties of a-Si films using modulation spectroscopy and polarization analysis, electronic states in the vicinity of the a-Si based thin film band end is examined using an ER method which is one of the modulation spectrometric methods. The constitution and electronic states of a-Si films are studied using a high-speed ion beam scattering method and electronic spectrometry. (NEDO)

Characteristics of the quarry as shielding for "2"4"1AmBe neutrons and monoenergetic photons

International Nuclear Information System (INIS)

Vega C, H. R.; Hernandez D, V. M.; Letechipia de L, C.; Salas L, M. A.; Rodriguez R, J. A.; Juarez A, C. A.

2016-09-01

Shielding is an important element in radiation protection since allows the management of radiation sources. Currently there are different materials of natural or anthropogenic origin that are used as shielding for both photons and neutrons. The quarry is a material of natural origin and abundant in our country, which is used in construction or for the manufacture of sculptures, however its characteristics as shielding have not been reported. In this paper we report some of the properties of the quarry as shielding for monoenergetic photons and for neutrons produced by an isotopic neutron source of "2"4"1AmBe. A quarry piece was used to determine its density and its chemical composition, with the XCOM code the elemental composition was determined and the mass interaction and total attenuation coefficients of the quarry were determined with photons of 10"-"3 to 10"-"5 MeV; the interaction coefficients included coherent dispersion, photoelectric absorption, Compton dispersion and the production of pairs in the nuclear and electronic field. Using the MCNP5 code, a narrow geometry attenuation experiment was modeled and the photon fluence was estimated that reaches a point detector at a distance of 42 cm from a point source, isotropic and monoenergetic photon when the source and the point detector were added quarry pieces of different thicknesses. The reduction of the number of photons as a function of the thickness of the quarry was used to determine the coefficient of linear attenuation of the quarry before photons of 0.03, 0.07, 0.1, 0.3, 1, 2 and 3 MeV that were the same as those calculated with the XCOM code. With the MCNP, the K a and H(10) transmission curves were also calculated. This same model was used to determined the variation of the "2"4"1AmBe neutron spectrum as a function of quarry thickness, as well as the E_R_O_T and H(10) transmission curves. (Author)

Nuclear-burst strength detecting and measuring device

International Nuclear Information System (INIS)

Balut, J.A.L.G.; Lemaire, P.E.G.K.; Loisy, C.M.

1976-01-01

A continuous-operation automatic device is described for detection and accurate measurement of the strength of a burst generating an emission from luminous or infrared sources. This device characterizes and analyzes the maxima and minima of a ''thermal flux/time'' curve. The device comprises a master time element and an assembly of photoelectric detectors, an electronic processing system coupled to the detectors, and a mechanical system securing the rigidity and positioning of the photoelectric detector assembly with respect to an octahedral prism based on a horizontal plane

Radiation-induced defects formation in Bi-containing vitreous chalcogenides

International Nuclear Information System (INIS)

Shpotyuk, O.; Vakiv, M.; Balitska, V.; Kovalskiy, A.

1997-01-01

Processes of formation and annihilation of coordination defects in As 2 Se 3 Bi y and (As 2 Se 3 )(Bi 2 Se 3 ) y amorphous chalcogenide semiconductors induced by influence of Co 60 gamma-irradiation are investigated by photoelectric spectroscopy method. It is obtained that radiation-induced changes of photoelectrical properties on bioconcentration of As 2 Se 3 Bi y glasses are characterized by anomalous concentration dependence. The nature of this effect is associated with diamagnetic coordination defects formation. (author). 19 refs, 3 figs

Double-gated Si NW FET sensors: Low-frequency noise and photoelectric properties

International Nuclear Information System (INIS)

Gasparyan, F.; Khondkaryan, H.; Arakelyan, A.; Zadorozhnyi, I.; Pud, S.; Vitusevich, S.

2016-01-01

The transport, noise, and photosensitivity properties of an array of silicon nanowire (NW) p"+-p-p"+ field-effect transistors (FETs) are investigated. The peculiarities of photosensitivity and detectivity are analyzed over a wide spectrum range. The absorbance of p-Si NW shifts to the short wavelength region compared with bulk Si. The photocurrent and photosensitivity reach increased values in the UV range of the spectrum at 300 K. It is shown that sensitivity values can be tuned by the drain-source voltage and may reach record values of up to 2–4 A/W at a wavelength of 300 nm at room temperature. Low-frequency noise studies allow calculating the photodetectivity values, which increase with decreasing wavelength down to 300 nm. We show that the drain current of Si NW biochemical sensors substantially depends on pH value and the signal-to-noise ratio reaches the high value of 10"5. Increasing pH sensitivity with gate voltage is revealed for certain source-drain currents of pH-sensors based on Si NW FETs. The noise characteristic index decreases from 1.1 to 0.7 with the growth of the liquid gate voltage. Noise behavior is successfully explained in the framework of the correlated number-mobility unified fluctuation model. pH sensitivity increases as a result of the increase in liquid gate voltage, thus giving the opportunity to measure very low proton concentrations in the electrolyte medium at certain values of the liquid gate voltage.

Imaging-therapy computed tomography with quasi-monochromatic X-rays.

Science.gov (United States)

Jost, Gregor; Golfier, Sven; Lawaczeck, Ruediger; Weinmann, Hanns-Joachim; Gerlach, Martin; Cibik, Levent; Krumrey, Michael; Fratzscher, Daniel; Rabe, Johannis; Arkadiev, Vladimir; Haschke, Michael; Langhoff, Norbert; Wedell, Reiner; Luedemann, Lutz; Wust, Peter; Pietsch, Hubertus

2008-12-01

Computed tomography (CT) is a widespread and highly precise technique working in the energy range around 50-100 keV. For radiotherapy, however, the MeV energy range enables a better dose distribution. This gap between diagnosis and therapy can be overcome by the use of a modified CT machine in combination with heavy elements targeted to the tumour and used as photoelectric radiation enhancer. The experimental setup consists of an X-ray optical module mounted at the exit of the X-ray tube of a clinical CT. The module converts the standard fan-shaped beam into a high intensity, monochromatized and focused beam. The radiation was characterized using an energy-dispersive detection system calibrated by synchrotron radiation and gel dosimetry. The photoelectric radiation enhancement for different elements was calculated and experimentally verified. The X-ray optical module filters selectively the energy of the tungsten K alpha-emission line (59.3 keV) with a full width at half maximum (FWHM) of 5 keV and focused the radiation onto a focal spot which coincides with the isocentre of the gantry. This results in a steep dose gradient at the centre of rotation qualified for locoregional radiation therapy. The photon energy of the quasi-monochromatic radiation agrees with the energy range of maximal photoelectric dose enhancement for gadolinium and iodine. An additional X-ray optical module optimized for targeted therapy and photoelectric dose enhancement allows the combination of diagnosis and radiotherapy on a clinical CT.

Application of AXUV photoelectric diode detector

International Nuclear Information System (INIS)

Yu Guogang; Pan Ningdong; Liu Yi

2006-01-01

Based on the photo-voltage effect of PN junction, two kinds of detector are introduced. Newly designed AXUV (Absolute Extreme Ultra Violet) photodiodes array radiation diagnostic system is installed in the HA-2A tokamak device. The advantages of AXUV detector are its near theoretical high quantum efficiency, high sensitivity, high responsibility, electromagnetic and vibration immunity, low price. (authors)

Photoelectric observations of propagating sunspot oscillations

International Nuclear Information System (INIS)

Lites, B.W.; White, O.R.; Packman, D.

1982-01-01

The Sacramento Park Observatory Vacuum Tower Telescope and diode array were used to make repeated intensity and velocity images of a large, isolated sunspot in both a chromospheric (lambda8542 Ca II) and a photospheric (lambda5576 Fe I) line. The movie of the digital data for the chromospheric line shows clearly a relationship between the propagating umbral disturbances and the running penumbral waves. The velocities for transverse propagating of the umbral and penumbral disturbances are 60--70 km s -1 and 20--35 km s -1 , respectively. Power spectra of the oscillations show a sharp peak at a period of about 170 s in both the velocity and intensity signals. The rms velocity fluctuation of this power peak is 0.26 km s -1 . The oscillations at any given point in the sunspot are very regular, and the phase relationship between the velocity and intensity of the chromospheric oscillations is radically different than that for the quiet Sun. Our preliminary interpretation of the phase relationship involves acoustic waves with wave vector directed downwards along the magnetic field lines; however, this interpretation relies on assumptions involved in the data reduction scheme. The mechanical energy flux carried by the observed umbral disturbances does not appear to be a significant contributor to the overall energy budget of the sunspot or the surrounding active region

The effect of illumination and electrode adjustment on the carrier behavior in special multilayer devices

Science.gov (United States)

Deng, Yanhong; Ou, Qingdong; Wang, Jinjiang; Zhang, Dengyu; Chen, Liezun; Li, Yanqing

2017-08-01

Intermediate connectors play an important role in semiconductor devices, especially in tandem devices. In this paper, four types of different intermediate connectors (e.g. Mg:Alq3/MoO3, MoO3, Mg:Alq3, and none) and two kinds of modified electrode materials (LiF and MoO3) integrated into the special multilayer devices are proposed, with the aim of studying the impact of light illumination and electrode adjustment on the carrier behavior of intermediate connectors through the current density-voltage characteristics, interfacial electronic structures, and capacitance-voltage characteristics. The results show that the illumination enhances the charge generation and separation in intermediate connectors, and further electrode interface modifications enhance the functionality of intermediate connectors. In addition, the device with an efficient intermediate connector structure shows a photoelectric effect, which paves the way for organic photovoltaic devices to realize optical-electrical integration transformation.

Study of a photomultiplier for the measurement of low light flows by photon counting

International Nuclear Information System (INIS)

Haye, Kleber

1964-01-01

After a recall of the history of the discovery and use of the photoemission effect, a presentation of the main characteristics of photomultipliers, a discussion of performance and weaknesses of electron multiplier-based cells, this research thesis addresses the study of low light flows. The author tried to determine whether it was possible, at ambient temperature, to reduce the influence of the thermoelectric effect. In order to do so, he made a detailed study of the amplitude spectrum of pulses of photoelectric origin. In order to analyse the influence of temperature of photomultiplier characteristics, he studied, with respect to temperature, the variation of the counting rate corresponding to darkness, the variation of pulse amplitude spectrum, and relative variations of the quantum efficiency for various wavelengths. In parallel with the study by counting, a study has been performed by using the well known mean current measurement [fr

A photodiode based on PbS nanocrystallites for FYTRONIX solar panel automatic tracking controller

Science.gov (United States)

Wageh, S.; Farooq, W. A.; Tataroğlu, A.; Dere, A.; Al-Sehemi, Abdullah G.; Al-Ghamdi, Ahmed A.; Yakuphanoglu, F.

2017-12-01

The structural, optical and photoelectrical properties of the fabricated Al/PbS/p-Si/Al photodiode based on PbS nanocrystallites were investigated. The PbS nanocrystallites were characterized by X-ray diffraction (XRD), UV-VIS-NIR, Infrared and Raman spectroscopy. The XRD diffraction peaks show that the prepared PbS nanostructure is in high crystalline state. Various electrical parameters of the prepared photodiode were analyzed from the electrical characteristics based on I-V and C-V-G. The photodiode has a high rectification ratio of 5.85×104 at dark and ±4 V. Moreover, The photocurrent results indicate a strong photovoltaic behavior. The frequency dependence of capacitance and conductance characteristics was attributed to depletion region behavior of the photodiode. The diode was used to control solar panel power automatic tracking controller in dual axis. The fabricated photodiode works as a photosensor to control Solar tracking systems.

Fluorescence imaging of reactive oxygen species by confocal laser scanning microscopy for track analysis of synchrotron X-ray photoelectric nanoradiator dose: X-ray pump-optical probe.

Science.gov (United States)

Jeon, Jae Kun; Han, Sung Mi; Kim, Jong Ki

2016-09-01

penetration by nanoradiators. In conclusion, the combined use of a synchrotron X-ray microbeam-irradiated three-dimensional ROS gel and confocal laser scanning fluorescence microscopy provides a simple dosimetry method for track analysis of X-ray photoelectric nanoradiator radiation, suggesting extensive cellular damage with dose-enhancement beyond a single cell containing IONs.

Method of estimation of scanning system quality

Science.gov (United States)

Larkin, Eugene; Kotov, Vladislav; Kotova, Natalya; Privalov, Alexander

2018-04-01

Estimation of scanner parameters is an important part in developing electronic document management system. This paper suggests considering the scanner as a system that contains two main channels: a photoelectric conversion channel and a channel for measuring spatial coordinates of objects. Although both of channels consist of the same elements, the testing of their parameters should be executed separately. The special structure of the two-dimensional reference signal is offered for this purpose. In this structure, the fields for testing various parameters of the scanner are sp atially separated. Characteristics of the scanner are associated with the loss of information when a document is digitized. The methods to test grayscale transmitting ability, resolution and aberrations level are offered.

Optical Graphene Gas Sensors Based on Microfibers: A Review

Directory of Open Access Journals (Sweden)

Yu Wu

2018-03-01

Full Text Available Graphene has become a bridge across optoelectronics, mechanics, and bio-chemical sensing due to its unique photoelectric characteristics. Moreover, benefiting from its two-dimensional nature, this atomically thick film with full flexibility has been widely incorporated with optical waveguides such as fibers, realizing novel photonic devices including polarizers, lasers, and sensors. Among the graphene-based optical devices, sensor is one of the most important branch, especially for gas sensing, as rapid progress has been made in both sensing structures and devices in recent years. This article presents a comprehensive and systematic overview of graphene-based microfiber gas sensors regarding many aspects including sensing principles, properties, fabrication, interrogating and implementations.

Nondestructive evaluation of differently doped InP wafers by time-resolved four-wave mixing technique

International Nuclear Information System (INIS)

Kadys, A.; Sudzius, M.; Jarasiunas, K.; Mao Luhong; Sun Niefeng

2006-01-01

Photoelectric properties of semi-insulating, differently doped, and undoped indium phosphide wafers, grown by the liquid encapsulation Czochralski method, have been investigated by time-resolved picosecond four-wave mixing technique. Deep defect related carrier generation, recombination, and transport properties were investigated experimentally by measuring four-wave mixing kinetics and exposure characteristics. The presence of deep donor states in undoped InP was confirmed by a pronounced effect of a space charge electric field to carrier transport. On the other hand, the recharging dynamics of electrically active residual impurities was observed in undoped and Fe-doped InP through the process of efficient trapping of excess carriers. The bipolar diffusion coefficients and mobilities were determined for the all wafers

Phenomenon detection device

International Nuclear Information System (INIS)

Suzuki, Yasuo.

1994-01-01

Detection signals for a specific phenomenon outputted from any of detectors are distributed by way of half mirrors and inputted to a logic discrimination circuit by way of a photoelectric convertor. The photoelectric convertor detects the quantity of light corresponding to the optical signals from more than two detectors which detected the phenomenon, and outputs detection signals to the logic discrimination circuit. If the phenomenon is detected, since both inputs turn ON in the logic discrimination circuit in accordance with the predetermined logical sum, the occurrence of a specific phenomenon is detected. Thus, an optical system substantially comprises half mirrors, reflection mirrors and photoelectric convertor in combination provides a logic circuit. Since the circuit which transmits signals of the detectors is constituted with an optical system using the half mirrors, the number of parts constituting the logic circuit can greatly be saved. In addition, since the optical system comprises mirrors or half mirrors which have been used so far, they can be used, once assembled, quasipermanently, and the reliability can be enhanced greatly. (N.H.)

Structure and optical properties of Ge/Si quantum dots formed by driving the evolution of Ge thin films via thermal annealing

Science.gov (United States)

Shu, Qijiang; Yang, Jie; Chi, Qingbin; Sun, Tao; Wang, Chong; Yang, Yu

2018-04-01

Ge/Si quantum dots (QDs) are fabricated by driving the transformation of a Ge thin film-deposited using the direct current (DC) magnetron sputtering technique by controlling the subsequent in situ annealing processes. The experimental results indicate that, with the increase in annealing temperature, the volume of Ge QDs increases monotonically, while the QD density initially increases then decreases. The maximal QD density can reach 1.1 × 1011 cm‑2 after a 10 min annealing at 650 °C. The Ge–Ge peak of Ge QDs obtained by Raman spectroscopy initially undergoes a blue shift and then a red shift with increasing annealing temperature. This behavior results from the competition between the dislocation and the strain relaxation in QDs. Concurrently, a series of photoelectric detectors are fabricated to evaluate the photoelectric performance of these annealed Ge QD samples. A high-photoelectricity response is demonstrated in the QD sample annealed at 650 °C. Our results pave a promising way for whole-silicon-material optical-electronic integration based on a simple and practicable fabrication method.

Anomalous Photovoltaic Response of Graphene-on-GaN Schottky Photodiodes.

Science.gov (United States)

Lee, Jae Hyung; Lee, Won Woo; Yang, Dong Won; Chang, Won Jun; Kwon, Sun Sang; Park, Won Il

2018-04-25

Graphene has attracted great attention as an alternative to conventional metallic or transparent conducting electrodes. Despite its similarities with conventional electrodes, recent studies have shown that a single-atom layer of graphene possesses unique characteristics, such as a tunable work function and transparencies for electric potential, reactivity, and wetting. Nevertheless, a systematic analysis of graphene and semiconductor junction characteristics has not yet been carried out. Here, we report the photoresponse characteristics of graphene-on-GaN Schottky junction photodiodes (Gr-GaN SJPDs), showing a typical rectifying behavior and distinct photovoltaic and photoelectric responses. Following the initial abrupt response to UV illumination, the Gr-GaN SJPDs exhibited a distinct difference in photocarrier dynamics depending on the applied bias voltage, which is characterized by either a negative or positive change in photocurrent with time. We propose underlying mechanisms for the anomalous photocarrier dynamics based on the interplay between electrostatic molecular interactions over the one-atom-thick graphene and GaN junction and trapped photocarriers at the defect states in the GaN thin film.

Imaging-therapy computed tomography with quasi-monochromatic X-rays

International Nuclear Information System (INIS)

Jost, Gregor; Golfier, Sven; Lawaczeck, Ruediger; Weinmann, Hanns-Joachim; Gerlach, Martin; Cibik, Levent; Krumrey, Michael; Fratzscher, Daniel; Rabe, Johannis; Arkadiev, Vladimir; Haschke, Michael; Langhoff, Norbert; Wedell, Reiner

2008-01-01

Introduction: Computed tomography (CT) is a widespread and highly precise technique working in the energy range around 50-100 keV. For radiotherapy, however, the MeV energy range enables a better dose distribution. This gap between diagnosis and therapy can be overcome by the use of a modified CT machine in combination with heavy elements targeted to the tumour and used as photoelectric radiation enhancer. Materials and methods: The experimental setup consists of an X-ray optical module mounted at the exit of the X-ray tube of a clinical CT. The module converts the standard fan-shaped beam into a high intensity, monochromatized and focused beam. The radiation was characterized using an energy-dispersive detection system calibrated by synchrotron radiation and gel dosimetry. The photoelectric radiation enhancement for different elements was calculated and experimentally verified. Results: The X-ray optical module filters selectively the energy of the tungsten Kα-emission line (59.3 keV) with a full width at half maximum (FWHM) of 5 keV and focused the radiation onto a focal spot which coincides with the isocentre of the gantry. This results in a steep dose gradient at the centre of rotation qualified for locoregional radiation therapy. The photon energy of the quasi-monochromatic radiation agrees with the energy range of maximal photoelectric dose enhancement for gadolinium and iodine. Conclusion: An additional X-ray optical module optimized for targeted therapy and photoelectric dose enhancement allows the combination of diagnosis and radiotherapy on a clinical CT

Imaging-therapy computed tomography with quasi-monochromatic X-rays

Energy Technology Data Exchange (ETDEWEB)

Jost, Gregor [Bayer Schering Pharma AG, Contrast Media Research, Muellerstrasse 178, 13353 Berlin (Germany)], E-mail: gregor.jost@bayerhealthcare.com; Golfier, Sven [Bayer Schering Pharma AG, Contrast Media Research, Muellerstrasse 178, 13353 Berlin (Germany)], E-mail: sven.golfier@bayerhealthcare.com; Lawaczeck, Ruediger [Bayer Schering Pharma AG, Contrast Media Research, Muellerstrasse 178, 13353 Berlin (Germany)], E-mail: ruediger.lawaczeck@bayerhealthcare.com; Weinmann, Hanns-Joachim [Bayer Schering Pharma AG, Contrast Media Research, Muellerstrasse 178, 13353 Berlin (Germany)], E-mail: hanns-joachim.weinmann@bayerhealthcare.com; Gerlach, Martin [Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, 10587 Berlin (Germany)], E-mail: martin.gerlach@ptb.de; Cibik, Levent [Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, 10587 Berlin (Germany)], E-mail: levent.cibik@ptb.de; Krumrey, Michael [Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, 10587 Berlin (Germany)], E-mail: michael.krumrey@ptb.de; Fratzscher, Daniel [Institute for Scientific Instruments GmbH, Rudower Chaussee 29/31, 12489 Berlin (Germany)], E-mail: Fratzscher@ifg-adlershof.de; Rabe, Johannis [Institute for Scientific Instruments GmbH, Rudower Chaussee 29/31, 12489 Berlin (Germany)], E-mail: Rabe@ifg-adlershof.de; Arkadiev, Vladimir [Institute for Scientific Instruments GmbH, Rudower Chaussee 29/31, 12489 Berlin (Germany)], E-mail: Arkadiev@ifg-adlershof.de; Haschke, Michael [Institute for Scientific Instruments GmbH, Rudower Chaussee 29/31, 12489 Berlin (Germany)], E-mail: Haschke@ifg-adlershof.de; Langhoff, Norbert [Institute for Scientific Instruments GmbH, Rudower Chaussee 29/31, 12489 Berlin (Germany)], E-mail: Langhoff@ifg-adlershof.de; Wedell, Reiner [Institut fuer angewandte Photonik e.V., Rudower Chaussee 29/31, 12489 Berlin (Germany)], E-mail: wedell-iap@ifg-adlershof.de (and others)

2008-12-15

Introduction: Computed tomography (CT) is a widespread and highly precise technique working in the energy range around 50-100 keV. For radiotherapy, however, the MeV energy range enables a better dose distribution. This gap between diagnosis and therapy can be overcome by the use of a modified CT machine in combination with heavy elements targeted to the tumour and used as photoelectric radiation enhancer. Materials and methods: The experimental setup consists of an X-ray optical module mounted at the exit of the X-ray tube of a clinical CT. The module converts the standard fan-shaped beam into a high intensity, monochromatized and focused beam. The radiation was characterized using an energy-dispersive detection system calibrated by synchrotron radiation and gel dosimetry. The photoelectric radiation enhancement for different elements was calculated and experimentally verified. Results: The X-ray optical module filters selectively the energy of the tungsten K{alpha}-emission line (59.3 keV) with a full width at half maximum (FWHM) of 5 keV and focused the radiation onto a focal spot which coincides with the isocentre of the gantry. This results in a steep dose gradient at the centre of rotation qualified for locoregional radiation therapy. The photon energy of the quasi-monochromatic radiation agrees with the energy range of maximal photoelectric dose enhancement for gadolinium and iodine. Conclusion: An additional X-ray optical module optimized for targeted therapy and photoelectric dose enhancement allows the combination of diagnosis and radiotherapy on a clinical CT.

Preparation of ultra-thin and high-quality WO{sub 3} compact layers and comparision of WO{sub 3} and TiO{sub 2} compact layer thickness in planar perovskite solar cells

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jincheng; Shi, Chengwu, E-mail: shicw506@foxmail.com; Chen, Junjun; Wang, Yanqing; Li, Mingqian

2016-06-15

In this paper, the ultra-thin and high-quality WO{sub 3} compact layers were successfully prepared by spin-coating-pyrolysis method using the tungsten isopropoxide solution in isopropanol. The influence of WO{sub 3} and TiO{sub 2} compact layer thickness on the photovoltaic performance of planar perovskite solar cells was systematically compared, and the interface charge transfer and recombination in planar perovskite solar cells with TiO{sub 2} compact layer was analyzed by electrochemical impedance spectroscopy. The results revealed that the optimum thickness of WO{sub 3} and TiO{sub 2} compact layer was 15 nm and 60 nm. The planar perovskite solar cell with 15 nm WO{sub 3} compact layer gave a 9.69% average and 10.14% maximum photoelectric conversion efficiency, whereas the planar perovskite solar cell with 60 nm TiO{sub 2} compact layer achieved a 11.79% average and 12.64% maximum photoelectric conversion efficiency. - Graphical abstract: The planar perovskite solar cell with 15 nm WO{sub 3} compact layer gave a 9.69% average and 10.14% maximum photoelectric conversion efficiency, whereas the planar perovskite solar cell with 60 nm TiO{sub 2} compact layer achieved a 11.79% average and 12.64% maximum photoelectric conversion efficiency. Display Omitted - Highlights: • Preparation of ultra-thin and high-quality WO{sub 3} compact layers. • Perovskite solar cell with 15 nm-thick WO{sub 3} compact layer achieved PCE of 10.14%. • Perovskite solar cell with 60 nm-thick TiO{sub 2} compact layer achieved PCE of 12.64%.

Solvent-Assisted Gel Printing for Micropatterning Thin Organic-Inorganic Hybrid Perovskite Films.

Science.gov (United States)

Jeong, Beomjin; Hwang, Ihn; Cho, Sung Hwan; Kim, Eui Hyuk; Cha, Soonyoung; Lee, Jinseong; Kang, Han Sol; Cho, Suk Man; Choi, Hyunyong; Park, Cheolmin

2016-09-27

While tremendous efforts have been made for developing thin perovskite films suitable for a variety of potential photoelectric applications such as solar cells, field-effect transistors, and photodetectors, only a few works focus on the micropatterning of a perovskite film which is one of the most critical issues for large area and uniform microarrays of perovskite-based devices. Here we demonstrate a simple but robust method of micropatterning a thin perovskite film with controlled crystalline structure which guarantees to preserve its intrinsic photoelectric properties. A variety of micropatterns of a perovskite film are fabricated by either microimprinting or transfer-printing a thin spin-coated precursor film in soft-gel state with a topographically prepatterned elastomeric poly(dimethylsiloxane) (PDMS) mold, followed by thermal treatment for complete conversion of the precursor film to a perovskite one. The key materials development of our solvent-assisted gel printing is to prepare a thin precursor film with a high-boiling temperature solvent, dimethyl sulfoxide. The residual solvent in the precursor gel film makes the film moldable upon microprinting with a patterned PDMS mold, leading to various perovskite micropatterns in resolution of a few micrometers over a large area. Our nondestructive micropatterning process does not harm the intrinsic photoelectric properties of a perovskite film, which allows for realizing arrays of parallel-type photodetectors containing micropatterns of a perovskite film with reliable photoconduction performance. The facile transfer of a micropatterned soft-gel precursor film on other substrates including mechanically flexible plastics can further broaden its applications to flexible photoelectric systems.

Radiation-induced defects formation in Bi-containing vitreous chalcogenides

Energy Technology Data Exchange (ETDEWEB)

Shpotyuk, O.; Vakiv, M.; Balitska, V.; Kovalskiy, A. [Institute of Materials, Lvov (Ukraine)

1997-12-01

Processes of formation and annihilation of coordination defects in As{sub 2}Se{sub 3}Bi{sub y} and (As{sub 2}Se{sub 3})(Bi{sub 2}Se{sub 3}){sub y} amorphous chalcogenide semiconductors induced by influence of Co{sup 60} gamma-irradiation are investigated by photoelectric spectroscopy method. It is obtained that radiation-induced changes of photoelectrical properties on bioconcentration of As{sub 2}Se{sub 3}Bi{sub y} glasses are characterized by anomalous concentration dependence. The nature of this effect is associated with diamagnetic coordination defects formation. (author). 19 refs, 3 figs.

Preparation and Optoelectrical Properties of p-CuO/n-Si Heterojunction by a Simple Sol-Gel Method

Science.gov (United States)

He, Bo; Xu, Jing; Ning, Huanpo; Zhao, Lei; Xing, Huaizhong; Chang, Chien-Cheng; Qin, Yuming; Zhang, Lei

The Cuprous oxide (CuO) thin film was prepared on texturized Si wafer by a simple sol-gel method to fabricate p-CuO/n-Si heterojunction photoelectric device. The novel sol-gel method is very cheap and convenient. The structural, optical and electrical properties of the CuO film were studied by X-ray diffraction (XRD), Scanning Electron Microscope (SEM), X-ray photoelectron spectroscopy (XPS), UV-Vis spectrophotometer and Hall effect measurement. A good nonlinear rectifying behavior is obtained for the p-CuO/n-Si heterojunction. Under reverse bias, good photoelectric behavior is obtained.

Influence of iodine on the electrical and photoelectrical properties of zinc phthalocyanine thin film devices

Energy Technology Data Exchange (ETDEWEB)

Sharma, G.D. [Jodhpur Univ. (India). Dept. of Physics; Sangodkar, S.G. [Jodhpur Univ. (India). Dept. of Physics; Roy, M.S. [Camouflage Division, Defence Laboratory, Jodhpur (Raj.) (India)

1996-11-01

The electrical and photovoltaic properties of the zinc phthalocyanine (ZnPc) and I{sub 2} doped ZnPc thin films, sandwiched between indium tin oxide (ITO) and Al electrodes, were investigated. Doping with iodine brings adequate changes in the characteristics of the device. The devices constitute a metal-insulator-semiconductor (MIS) structure, in which depletion layer is formed in ZnPc, near Al-Al{sub 2}O{sub 3}/ZnPc. The depletion layer width and potential barrier height decrease with I{sub 2} doping. The charge transport phenomenon at higher voltage range appears to be space charge limited conduction (SCLC), in the presence of the discrete trapping level. The position of Fermi level shifts toward the valence band edge, which indicates that I{sub 2} doping increases the P-type conductivity. Various electrical and photovoltaic parameters were determined from the J-V and C-V analysis. The influence of the I{sub 2} doping has been discussed in detail. (orig.)

Preparation and electric and photoelectric properties of thin deposits of Fe, Co, Ni, Cu, Ag, Au and Pd

International Nuclear Information System (INIS)

Heras, J.M.; Albano, E.V.; Asensio, M.C.; Viscido, L.

1984-01-01

The physics chemical properties of desordered metallic thin films of Fe, Co, Ni, Pd, Ag, Cu and Au are of great interest for its catalitic activity and for its application in radiation absorption of solar cells and micro electronic devices. This work has the purpose of reporting the experimental results obtained by evaporated films of these metals, which present desordered characteristics, small crystal size and high surface-volume rate. (A.C.A.S.) [pt

CUSTOM RELAXATION INDUCED IMPURITY PHOTOCONDUCTIVITY IN THE UNITED AII BVI and AIII BV

Directory of Open Access Journals (Sweden)

L. B. Atlukhanova

2016-01-01

Full Text Available Two types of non-standard relaxation induced impurity photoconductivity (IIP observed in photoconductors CdS, ZnSe, GaAs and others, depending on the kinetic characteristics of the traps are described. In one case, at the stage of post flashing monotonic decay which is typical for relaxation associated with slow traps (the ratio of the speed of the electron capture to the recombination rate (R << 1, the photo response is experiencing vibrations of low frequency (f =0.03-0.3Hz. Relaxation of the second type characterized by rapid photoelectric traps (R >> 1: measurement alternating signal (f > 20 Hz relaxation curves take the form of curves usual impurity photoconductivity. Electronic processes responsible for relaxation of non-standard IIP are analyzed. For example, fast-centers, which include the characteristic AIIBVI donor Agi0, for the first time in semiconductors experimentally, investigated the dependence of the cross section of electron capture by traps energy released during localization.

Characteristics of liver tissue for attenuate the gamma radiation; Caracteristicas del tejido hepatico para atenuar la radiacion gamma

Energy Technology Data Exchange (ETDEWEB)

Arcos P, A.; Rodriguez N, S.; Pinedo S, A.; Amador V, P.; Chacon R, A.; Vega C, H.R. [Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

2005-07-01

It was determined the lineal attenuation coefficient of hepatic tissue before gamma radiation of a source of {sup 137} Cs. When exposing organic material before X or gamma radiation fields, part of the energy of the photons is absorbed by the material, while another part crosses it without producing any effect. The quantity of energy that is absorbed is a measure of the dose that receives the material. The three main mechanisms by means of which the gamma rays interacting with the matter are: The Photoelectric Effect, the Compton dispersion and the Even production; the sum of these three processes is translated in the attenuation coefficient of the radiation. In this work we have used hepatic tissue of bovine, as substitute of the human hepatic tissue, and we have measured the lineal attenuation coefficient for photons of 0.662 MeV. Through a series of calculations we have determined the lineal attenuation coefficient for photons from 10{sup -3} to 10{sup -5} MeV and the measured coefficient was compared with the one calculated. (Author)

Character of photovoltaic/thermal hybrid collector. Character analysis by numerical calculation; Taiyoko netsu hybrid collector no tokusei. Suchi keisan ni yoru tokusei kaiseki

Energy Technology Data Exchange (ETDEWEB)

Morita, Y; Iwawaki, T; Fujisawa, T; Tani, T [Science University of Tokyo, Tokyo (Japan)

1997-11-25

In order to investigate characteristics of photovoltaic (PV)/thermal hybrid collectors (PV/T{sub s}) operating under varying conditions, energy equilibrium equations have been developed for numerical calculation, and the calculated results were compared with the observed ones. The calculated characteristics are close to the observed ones, both for photoelectric conversion and heat collecting characteristics, demonstrating validity of these energy equations. It is found, by comparing characteristics of PV/T{sub A} (covered with glass) with those of PV/T{sub B} (not covered with glass), that these characteristics are greatly affected by glass cover. Maximum overall excergy levels attained are 13.29% with PV/T{sub A} and 11.48% with PV/T{sub B} under the conditions of solar radiation intensity H: 800W/m{sup 2}, ambient temperature: 20degC and wind velocity: 0.5m/s, where flow rates of heat medium are 2.0times10{sup -3} and 4.0times10{sup -3}kg/s, respectively. Thus, the PV/T{sub A} system has a higher maximum excergy efficiency than the PV/T{sub B} system. The PV/T{sub A} gives water of higher temperature, demonstrating that covering the system with glass increases maximum excergy efficiency and optimum temperature. 6 refs., 5 figs., 2 tabs.

Investment characteristics, stock characteristics and portfolio diversification of finance professionals

OpenAIRE

Mohammad Tariqul Islam Khan; Siow-Hooi Tan; Lee-Lee Chong; Hway-Boon Ong

2017-01-01

This study estimates if Malaysian finance professionals' investment characteristics and stock characteristics' preferences affect their portfolio diversification, and whether the effects of these predictors vary across professionals' gender, income and experience. Employing a survey and ordinal regression models, the findings demonstrate that investment characteristics such as active trading, usage of internet and telephone, and saving for retirement objective are likely to improve diversific...

High performance p-i-n CdTe and CdZnTe detectors

CERN Document Server

Khusainov, A K; Ilves, A G; Morozov, V F; Pustovoit, A K; Arlt, R D

1999-01-01

A breakthrough in the performance of p-i-n CdTe and CdZnTe detectors is reported. The detector stability has been significantly improved, allowing their use in precise gamma and XRF applications. Detectors with energy resolution close to Si and Ge were produced operating with only -30--35 deg. C cooling (by a Peltier cooler of 15x15x10 mm size and a consumed power less than 5 W). Presently detectors with volume of up to 300 mm sup 3 are available. In terms of photoelectric effect efficiency it corresponds to HPGe detectors with volumes of about 1.5 cm sup 3. The possibilities of further improvement of CdTe and CdZnTe detector characteristics are discussed in this paper.

[Analysis of H2S/PH3/NH3/AsH3/Cl2 by Full-Spectral Flame Photometric Detector].

Science.gov (United States)

Ding, Zhi-jun; Wang, Pu-hong; Li, Zhi-jun; Du, Bin; Guo, Lei; Yu, Jian-hua

2015-07-01

Flame photometric analysis technology has been proven to be a rapid and sensitive method for sulfur and phosphorus detection. It has been widely used in environmental inspections, pesticide detection, industrial and agricultural production. By improving the design of the traditional flame photometric detector, using grating and CCD sensor array as a photoelectric conversion device, the types of compounds that can be detected were expanded. Instead of a single point of characteristic spectral lines, full spectral information has been used for qualitative and quantitative analysis of H2S, PH3, NH3, AsH3 and Cl2. Combined with chemometric method, flame photometric analysis technology is expected to become an alternative fast, real-time on-site detection technology to simultaneously detect multiple toxic and harmful gases.

Synthesis and characterization of natural dye and counter electrode thin films with different carbon materials for dye-sensitized solar cells.

Science.gov (United States)

Chang, Ho; Chen, Tien-Li; Kao, Mu-Jung; Chen, Chih-Hao; Chien, Shu-Hua; Jiang, Lii-Jenq

2011-08-01

This study aims to deal with the film of the counter electrode of dye-sensitized solar cells (DSSCs) and the preparation, structure and characteristics of the extract of natural dye. This study adopts different commercial carbon materials such as black lead, carbon black and self-made TiO2-MWCNT compound nanoparticle as the film of the counter electrodes. Moreover, for the preparation of natural dyes, anthocyanins and chlorophyll dyes are extracted from mulberry and pomegranate respectively. Furthermore, the extracted anthocyanins and chlorophyll are blended into cocktail dye to complete the preparation of natural dye. Results show that the photoelectric conversion efficiency of the single-layer TiO2-MWCNT counter electrode film and the cocktail dye of the DSSCs is 0.462%.

Influences of the CdS nanoparticles grown strategies on CdTe nanorods array films: A comparison between successive ionic layer absorption and reaction and chemical bath deposition

International Nuclear Information System (INIS)

Wang, Jun; Zhou, Xiaoming; Lv, Pin; Yang, Lihua; Ding, Dong; Niu, Jiasheng; Liu, Li; Li, Xue; Fu, Wuyou; Yang, Haibin

2016-01-01

The cadmium sulfide (CdS) film is deposited on the surface of cadmium telluride (CdTe) nanorods (NRs) by two different methods, successive ionic layer adsorption and reaction (SILAR) and chemical bath deposition (CBD) techniques. The influence of the deposition parameters on the properties of the films is investigated. Compared to SILAR, CBD is a simple and time saving technique, which can ensure full coverage and better growth of CdS on the surface of CdTe NRs. The photovoltaic characteristics of CdS sensitized CdTe films are also investigated. It is found that the CdTe/CBD-CdS thin film demonstrates excellent photoelectrical properties, which is ascribed to the large absorption coefficient of the material, indicating the potential applications in solar cells.

ENERGY CHARACTERISTICS OF ETHANOL CHARACTERISTICS ...

African Journals Online (AJOL)

eobe

CHARACTERISTICS OF ETHANOL-DIESEL MIX FOR AUTOMOTIVE. DIESEL ... diesel engine and the engine speed, torque, power and specific fuel consumption (sfc) were determine .... heated on an electric stove and stirred continuously.

Nuclear reactor and production systems with digital controls

International Nuclear Information System (INIS)

Luger, P.P.

1976-01-01

Several digital sensing devices are described for use in automated production systems. The first described is for use in the automatic operation of a reactor. This device employs a binant electrometer using a quartz fiber mounted at one end but free to vibrate at the other in an AC field. The fiber oscillates if a charge is placed upon it. An optical slit replaces the ordinary eyepiece reticule scale. With the quartz fiber adjusted so its image is in focus at the optical slit, photoelectric signals are obtained at null charge on the fiber. The quartz fiber is repeatedly charged and allowed to discharge by collecting ions from a source under measurement. Each photoelectric signal causes a digital time reading to be taken. The time readings are used to evaluate the current due to the collected charge. The photoelectric signals, by feedback, also operate the electrometer for continuous or intermittent-continuous operation. Basically, the system is a current digitizer. Application is made to reactor monitoring and control as well as to other types of production systems. Finally, other types of sensing devices are also described and their use in automated controlled processes is shown. 3 claims, 19 figures

The Low-Temperature Crystallization and Interface Characteristics of ZnInSnO/In Films Using a Bias-Crystallization Mechanism

International Nuclear Information System (INIS)

Chen, K. J.; Chen, K.J.; Hung, F.Y.; Lui, T.S.; Chang, S.J.; Hu, Z.S.

2012-01-01

This study presents a successful bias crystallization mechanism (BCM) based on an indium/glass substrate and applies it to fabrication of ZnInSnO (ZITO) transparent conductive oxide (TCO) films. The effects of bias-crystallization on electrical and structural properties of ZITO/In structure indicate that the current-induced Joule heating and interface diffusion were critical factors for low-temperature crystallization. With biases of 4 V and 0.1 A, the resistivity of the ZITO film was reduced from 3.08x10 -4 Ω * cm to 6.3x10 -5 Ω * cm. This reduction was attributed to the bias-induced energy, which caused indium atoms to diffuse into the ZITO matrix. This effectuated crystallizing the amorphous ZITO (a-ZITO) matrix at a lower temperature (approximately 170 degree C) for a short period (≤20 min) during a bias test. The low-temperature BCM developed for this study obtained an efficient conventional annealed treatment (higher temperature), possessed energy-saving and speed advantages, and can be considered a candidate for application in photoelectric industries.

Scattering-layer-induced energy storage function in polymer-based quasi-solid-state dye-sensitized solar cells.

Science.gov (United States)

Zhang, Xi; Jiang, Hongrui

2015-03-09

Photo-self-charging cells (PSCs) are compact devices with dual functions of photoelectric conversion and energy storage. By introducing a scattering layer in polymer-based quasi-solid-state dye-sensitized solar cells, two-electrode PSCs with highly compact structure were obtained. The charge storage function stems from the formed ion channel network in the scattering layer/polymer electrolyte system. Both the photoelectric conversion and the energy storage functions are integrated in only the photoelectrode of such PSCs. This design of PSC could continuously output power as a solar cell with considerable efficiency after being photo-charged. Such PSCs could be applied in highly-compact mini power devices.

Photorefractive IR-spectrum composites prepared from polyimide and ruthenium(II) tetra-15-crown-5-phthalocyaninate with axially coordinated triethylenediamine molecules

International Nuclear Information System (INIS)

Vannikov, A.V.; Grishina, A.D.; Gorbunova, Yu.G.; Enakieva, Yu.Yu.; Krivenko, T.V.; Savel'ev, V.V.; Tsivadze, A.Yu.

2006-01-01

Photoelectric, non-linear optical, and photorefractive properties of aromatic polyimine doped with ruthenium(II) complex with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules, (R 4 Pc)Ru(TED) 2 , where R 4 Pc 2- and TED denote 4,5,4',5',4'',5'',4''',5'''-tetrakis-(1,4,7,10,13- pentaoxatridecamethylene)phthalocyaninate ion and triethylenediamine molecule, respectively, were studied. It is established that supramolecular ensembles on the basis of the complex make an aromatic polyimide layer photoelectrically sensitive to 1064-nm Nd : YAG laser radiation, exhibit third-order susceptibility, and, consequently, impart photorefractive properties to the polymer layer at this wavelength [ru

Characteristic Comparison of CHD for Active Smoker by Smoking Characteristic

OpenAIRE

Diastutik, Desy

2016-01-01

Coronary Heart Disease (CHD) is a type of cardiovascular disease that has highest level of morbidity and mortality among non communicable disease group. One of the factor that contribute for coronary heart disease is smoking characteristic. The research was aimed to analyze characteristic comparison of coronary heart disease for active smoker by smoking characteristic. The research was observational study using cross sectional design. Thirty eight active smokers were involved as research samp...

MODEL OF EMERGENCY DEPARTMENT NURSE PERFORMANCE IMPROVEMENT BASED ON ASSOCIATION OF INDIVIDUAL CHARACTERISTIC, ORGANIZATION CHARACTERISTIC AND JOB CHARACTERISTIC

Directory of Open Access Journals (Sweden)

Maria Margaretha Bogar

2017-04-01

Full Text Available Introduction: Nursing care is integral part of health care and having important role in management of patient with emergency condition. The purpose of this research was to develop nurse performance improvement model based on individual, organization and job characteristics association in Emergency Department of RSUD dr TC Hillers Maumere. Method: This was an explanative survey by cross sectional approach held on July -August 2012. Respondents in this study were 22 nurses and 44 patients were obtained by purposive sampling technique. Data were analyzed by partial least square test and signi fi cant t value > 1.64 (alpha 10%. Result: Results showed that individual characteristic had effect on nurse performance (t = 7.59, organization characteristic had effect on nurse performance (t = 2.03 and job characteristic didn’t have effect on nurse performance (t = 0.88. Nurse performance had effect on patient satisfaction (t = 6.54 but nurse satisfaction didn’t have effect on nurse performance (t = 1.31, and nurse satisfaction didn’t have effect either on patient satisfaction (t = 0.94. Discussion: This research concluded that individual characteristics which in fl uence nurse performance in nursing care were ability and skill, experience, age, sex, attitude and motivation. Organization characteristic that influence nurse performance was reward while job characteristic that include job design and feedback didn’t influence nurse performance in nursing care. Nurse performance influenced patient satisfaction but nurse satisfaction didn’t influence patient satisfaction and nurse performance.

Mexican-American Adolescents’ Gender-Typed Characteristics: The Role of Sibling and Friend Characteristics

Science.gov (United States)

Wheeler, Lorey A.; Updegraff, Kimberly A.; Schaefer, David R.

2016-01-01

This study examined the role of sibling and friend characteristics in Mexican-American youth’s gender-typed characteristics (i.e., attitudes, interests, and leisure activities) in early versus middle adolescence using a sibling design. Mexican-American 7th graders (M = 12.51 years; SD = .58) and their older siblings (M = 15.48 years; SD = 1.57) from 246 families participated in home interviews and a series of seven nightly phone calls. Results revealed that younger/early adolescent siblings reported more traditional gender role attitudes than their older/middle adolescent siblings and older brothers were more traditional in their attitudes than older sisters. When comparing siblings’ gender-typed interests and leisure activities, boys reported more masculine orientations than girls and girls reported more feminine orientations than boys. Older brothers’ gender-typed characteristics were associated with the amount of time spent with and gender characteristics of their friendship group, but for younger brothers, sibling characteristics were associated with their gender-typed characteristics. In contrast, both sibling and friendship characteristics were significantly associated with older and younger sisters’ gender-typed characteristics. The discussion addressed the different correlates of older and younger sisters’ and brothers’ gender-typed characteristics. PMID:25539774

Mexican-American Adolescents' Gender-Typed Characteristics: The Role of Sibling and Friend Characteristics.

Science.gov (United States)

Perez-Brena, Norma J; Wheeler, Lorey A; Updegraff, Kimberly A; Schaefer, David R

2015-07-01

This study examined the role of sibling and friend characteristics in Mexican-American youth's gender-typed characteristics (i.e., attitudes, interests, and leisure activities) in early versus middle adolescence using a sibling design. Mexican-American 7th graders (M = 12.51 years; SD = .58) and their older siblings (M = 15.48 years; SD = 1.57) from 246 families participated in home interviews and a series of seven nightly phone calls. Results revealed that younger/early adolescent siblings reported more traditional gender role attitudes than their older/middle adolescent siblings and older brothers were more traditional in their attitudes than older sisters. When comparing siblings' gender-typed interests and leisure activities, boys reported more masculine orientations than girls and girls reported more feminine orientations than boys. Older brothers' gender-typed characteristics were associated with the amount of time spent with and gender characteristics of their friendship group, but for younger brothers, sibling characteristics were associated with their gender-typed characteristics. In contrast, both sibling and friendship characteristics were significantly associated with older and younger sisters' gender-typed characteristics. The discussion addressed the different correlates of older and younger sisters' and brothers' gender-typed characteristics.

Photoelectric Radial Velocities, Paper XIX Additional Spectroscopic ...

Indian Academy of Sciences (India)

ian velocity curve that does justice to the measurements, but it cannot be expected to have much predictive power. Key words. Stars: late-type—stars: radial velocities—spectroscopic binaries—orbits. 0. Preamble. The 'Redman K stars' are a lot of seventh-magnitude K stars whose radial velocities were first observed by ...

Photoelectric sensor output controlled by eyeball movements

Science.gov (United States)

1965-01-01

The difference between the infrared absorption of the iris and infrared reflectivity of the eyeball controls the operation of a device consisting of an infrared source and amplifier, a cadmium selenide infrared sensor, and an infrared filter.

Comparison of Magnetic Characteristics of Powder Magnetic Core and Evaluation of Motor Characteristics

Science.gov (United States)

Enomoto, Yuji; Ito, Motoya; Masaki, Ryozo; Yamazaki, Katsuyuki; Asaka, Kazuo; Ishihara, Chio; Ohiwa, Syoji

A magnetic characteristic measurement, a motor characteristic forecast, and an experimental evaluation of various powder magnetic cores were performed aiming at a fixed quantity grasp when the powder magnetic core was applied to the motor core as the magnetic material. The manufacturing conditions were changed, and magnetic characteristic compares a direct current magnetization characteristic and an iron disadvantageous characteristic with the silicon steel board for a different powder magnetic core. Therefore, though some permeabilities are low, characteristics almost equal to those of a silicon steel board were obtained in the maximum saturation magnetic induction, which confirms that the powder magnetic core in disadvantageous iron in a certain frequency domain, and to confirm disadvantageous iron lowers. Moreover, it has been shown to obtain characteristics almost equal to the silicon steel board when compared in terms of motor efficiency, though some disadvantageous iron increases since the effect when applying to the motor is verified the silicon steel board and the comparison evaluation for the surface type permanent magnet motor.

Quantifying physical characteristics of wildland fuels using the fuel characteristic classification system.

Science.gov (United States)

Cynthia L. Riccardi; Susan J. Prichard; David V. Sandberg; Roger D. Ottmar

2007-01-01

Wildland fuel characteristics are used in many applications of operational fire predictions and to understand fire effects and behaviour. Even so, there is a shortage of information on basic fuel properties and the physical characteristics of wildland fuels. The Fuel Characteristic Classification System (FCCS) builds and catalogues fuelbed descriptions based on...

Large - scale Rectangular Ruler Automated Verification Device

Science.gov (United States)

Chen, Hao; Chang, Luping; Xing, Minjian; Xie, Xie

2018-03-01

This paper introduces a large-scale rectangular ruler automated verification device, which consists of photoelectric autocollimator and self-designed mechanical drive car and data automatic acquisition system. The design of mechanical structure part of the device refer to optical axis design, drive part, fixture device and wheel design. The design of control system of the device refer to hardware design and software design, and the hardware mainly uses singlechip system, and the software design is the process of the photoelectric autocollimator and the automatic data acquisition process. This devices can automated achieve vertical measurement data. The reliability of the device is verified by experimental comparison. The conclusion meets the requirement of the right angle test procedure.

Technical presentation

CERN Document Server

FP Department

2009-01-01

07 April 2009 Technical presentation by Leuze Electronics: 14.00 – 15.00, Main Building, Room 61-1-017 (Room A) Photoelectric sensors, data identification and transmission systems, image processing systems. We at Leuze Electronics are "the sensor people": we have been specialising in optoelectronic sensors and safety technology for accident prevention for over 40 years. Our dedicated staff are all highly customer oriented. Customers of Leuze Electronics can always rely on one thing – on us! •\tFounded in 1963 •\t740 employees •\t115 MEUR turnover •\t20 subsidiaries •\t3 production facilities in southern Germany Product groups: •\tPhotoelectric sensors •\tIdentification and measurements •\tSafety devices

An assessment on seasonal analysis of wind energy characteristics and wind turbine characteristics

International Nuclear Information System (INIS)

Akpinar, E. Kavak; Akpinar, S.

2005-01-01

This paper presents seasonal variations of the wind characteristics and wind turbine characteristics in the regions around Elazig, namely Maden, Agin and Keban. Mean wind speed data in measured hourly time series format is statistically analyzed for the six year period 1998-2003. The probability density distributions are derived from the time series data and their distributional parameters are identified. Two probability density functions are fitted to the measured probability distributions on a seasonal basis. The wind energy characteristics of all the regions is studied based on the Weibull and Rayleigh distributions. Energy calculations and capacity factors for the wind turbine characteristics were determined for wind machines of different sizes between 300 and 2300 kW. It was found that Maden is the best region, among the regions analyzed, for wind characteristics and wind turbine characteristics

Payment Instrument Characteristics

DEFF Research Database (Denmark)

Holst, Jacques; Kjeldsen, Martin; Hedman, Jonas

2015-01-01

Over the last decade, we have witnessed payment innovations that fundamentally have changed the ways we pay. Payment innovations, such as mobile payments and on-line banking, include characteristics or features that are essential to understand if we want to know how and why payers choose among...... payment innovations. Using the Repertory Grid technique to explore 15 payers’ perception of six payment instruments, including coins, banknotes, debit cards, credit cards, mobile payments, and on-line banking, we identify 16 payment characteristics. The characteristics aggregate seventy-six unique...

Tuning the Electron-Transport and Electron-Accepting Abilities of Dyes through Introduction of Different π-Conjugated Bridges and Acceptors for Dye-Sensitized Solar Cells.

Science.gov (United States)

Li, Yuanzuo; Sun, Chaofan; Song, Peng; Ma, Fengcai; Yang, Yanhui

2017-02-17

A series of dyes, containing thiophene and thieno[3,2-b]thiophene as π-conjugated bridging units and six kinds of groups as electron acceptors, were designed for dye-sensitized solar cells (DSSCs). The ground- and excited-state properties of the designed dyes were investigated by using density functional theory (DFT) and time-dependent DFT, respectively. Moreover, the parameters affecting the short-circuit current density and open-circuit voltage were calculated to predict the photoelectrical performance of each dye. In addition, the charge difference density was presented through a three-dimensional (3D) real-space analysis method to investigate the electron-injection mechanism in the complexes. Our results show that the longer conjugated bridge would inhibit the intramolecular charge transfer, thereby affecting the photoelectrical properties of DSSCs. Similarly, owing to the lowest chemical hardness, largest electron-accepting ability, dipole moment (μnormal ) and the change in the energy of the TiO 2 conduction band (ΔECB ), the dye with a (E)-3-(4-(benzo[c][1,2,5]thiadiazol-4-yl)phenyl)-2-cyanoacrylic acid (TCA) acceptor group would exhibit the most significant photoelectrical properties among the designed dyes. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Shaped detector

International Nuclear Information System (INIS)

Carlson, R.W.

1981-01-01

A radiation detector or detector array which has a non-constant spatial response, is disclosed individually and in combination with a tomographic scanner. The detector has a first dimension which is oriented parallel to the plane of the scan circle in the scanner. Along the first dimension, the detector is most responsive to radiation received along a centered segment of the dimension and less responsive to radiation received along edge segments. This non-constant spatial response can be achieved in a detector comprised of a scintillation crystal and a photoelectric transducer. The scintillation crystal in one embodiment is composed of three crystals arranged in layers, with the center crystal having the greatest light conversion efficiency. In another embodiment, the crystal is covered with a reflective substance around the center segment and a less reflective substance around the remainder. In another embodiment, an optical coupling which transmits light from adjacent the center segment with the greatest intensity couples the scintillation crystal and the photoelectric transducer. In yet another embodiment, the photoelectric transducer comprises three photodiodes, one receiving light produced adjacent the central segment and the other two receiving light produced adjacent the edge segments. The outputs of the three photodiodes are combined with a differential amplifier

Photoelectrode Fabrication of Dye-Sensitized Nanosolar Cells Using Multiple Spray Coating Technique

Directory of Open Access Journals (Sweden)

Chien-Chih Chen

2013-01-01

Full Text Available This paper presents a spray coating technique for fabricating nanoporous film of photoelectrode in dye-sensitized nanosolar cells (DSSCs. Spray coating can quickly fabricate nanoporous film of the photoelectrode with lower cost, which can further help the DSSCs to be commercialized in the future. This paper analyzed photoelectric conversion efficiency of the DSSCs using spray coated photoelectrode in comparison with the photoelectrode made with the doctor blade method. Spray coating can easily control transmittance of the photoelectrode through the multiple spray coating process. This work mainly used a dispersant with help of ultrasonic oscillation to prepare the required nano-TiO2 solution and then sprayed it on the ITO glasses. In this work, a motor-operated conveyor belt was built to transport the ITO glasses automatically for multiple spray coating and drying alternately. Experiments used transmittance of the photoelectrode as a fabrication parameter to analyze photoelectric conversion efficiency of the DSSCs. The influencing factors of the photoelectrode transmittance during fabrication are the spray flow rate, the spray distance, and the moving speed of the conveyor belt. The results show that DSSC with the photoelectrode transmittance of ca. 68.0 ± 1.5% and coated by the spray coating technique has the best photoelectric conversion efficiency in this work.

Work Practice Characteristics

DEFF Research Database (Denmark)

Pors, Jens Kaaber; Simonsen, Jesper

2003-01-01

and work practice. To understand these issues a framework of characteristics is identified and termed work practice characteristics to describe important aspects of the hybrid configuration of groupware and situated work practices. Drawing on concepts and work practice studies in the field of computer...... investigation of how groupware is employed to support new ways of working in a large European financial organisation are analysed to illustrate situations with high and low integration of groupware. The framework of work practice characteristics is discussed in the light of these findings and implications...

Cauchy problem for differential operators with double characteristics non-effectively hyperbolic characteristics

CERN Document Server

Nishitani, Tatsuo

2017-01-01

Combining geometrical and microlocal tools, this monograph gives detailed proofs of many well/ill-posed results related to the Cauchy problem for differential operators with non-effectively hyperbolic double characteristics. Previously scattered over numerous different publications, the results are presented from the viewpoint that the Hamilton map and the geometry of bicharacteristics completely characterizes the well/ill-posedness of the Cauchy problem. A doubly characteristic point of a differential operator P of order m (i.e. one where Pm = dPm = 0) is effectively hyperbolic if the Hamilton map FPm has real non-zero eigenvalues. When the characteristics are at most double and every double characteristic is effectively hyperbolic, the Cauchy problem for P can be solved for arbitrary lower order terms. If there is a non-effectively hyperbolic characteristic, solvability requires the subprincipal symbol of P to lie between − Pµj and P µj , where iµj are the positive imaginary eigenvalues of FPm ....

Prototype Early Warning Fire Detection System: Test Series 4 Results

National Research Council Canada - National Science Library

Gottuk, Daniel

2002-01-01

.... The use of multiple sensors and the Probabilistic Neural Networks alarm algorithm in the EWFD system resulted in improved performance compared to only an ionization or photoelectric smoke detector...

E-Glider: Active Electrostatic Flight for Airless Body Exploration

Data.gov (United States)

National Aeronautics and Space Administration — The environment near the surface of airless bodies (asteroids, comets, Moon) is electrically charged due to Sun's photoelectric bombardment. Charged dust is ever...

The Influence of Electrophoretic Deposition for Fabricating Dye-Sensitized Solar Cell

Directory of Open Access Journals (Sweden)

Jung-Chuan Chou

2014-01-01

Full Text Available Titanium dioxide (TiO2 film was deposited on fluorine-doped tin oxide (FTO glass substrate by electrophoretic deposition method (EPD. TiO2 films were prepared with different I2 dosages, electric field intensities and deposition time (D.T., electrophotic deposition times. By different I2 dosages, electric field intensities, deposition time, electrophotic deposition times fabricated TiO2 films and compared photoelectric characteristics of TiO2 films to find optimal parameters which were the highest photovoltaic conversion efficiency. And use electrochemical impedance spectroscopy (EIS to measure the Nyquist plots under different conditions and analyze the impendence of dye-sensitized solar cells at the internal heterojunction. According to the experimental results, the I2 dosage was 0.025 g which obtained the optimal characteristic parameters. Thickness of TiO2 film was 10.6 μm, the open-circuit voltage (Voc was 0.77 V, the short-circuit current density (Jsc was 7.20 mA/cm2, the fill factor (F.F. was 53.41%, and photovoltaic conversion efficiency (η was 2.96%.

Power calculation of linear and angular incremental encoders

Science.gov (United States)

Prokofev, Aleksandr V.; Timofeev, Aleksandr N.; Mednikov, Sergey V.; Sycheva, Elena A.

2016-04-01

Automation technology is constantly expanding its role in improving the efficiency of manufacturing and testing processes in all branches of industry. More than ever before, the mechanical movements of linear slides, rotary tables, robot arms, actuators, etc. are numerically controlled. Linear and angular incremental photoelectric encoders measure mechanical motion and transmit the measured values back to the control unit. The capabilities of these systems are undergoing continual development in terms of their resolution, accuracy and reliability, their measuring ranges, and maximum speeds. This article discusses the method of power calculation of linear and angular incremental photoelectric encoders, to find the optimum parameters for its components, such as light emitters, photo-detectors, linear and angular scales, optical components etc. It analyzes methods and devices that permit high resolutions in the order of 0.001 mm or 0.001°, as well as large measuring lengths of over 100 mm. In linear and angular incremental photoelectric encoders optical beam is usually formulated by a condenser lens passes through the measuring unit changes its value depending on the movement of a scanning head or measuring raster. Past light beam is converting into an electrical signal by the photo-detecter's block for processing in the electrical block. Therefore, for calculating the energy source is a value of the desired value of the optical signal at the input of the photo-detecter's block, which reliably recorded and processed in the electronic unit of linear and angular incremental optoelectronic encoders. Automation technology is constantly expanding its role in improving the efficiency of manufacturing and testing processes in all branches of industry. More than ever before, the mechanical movements of linear slides, rotary tables, robot arms, actuators, etc. are numerically controlled. Linear and angular incremental photoelectric encoders measure mechanical motion and

To argumentate in quantum physics. Instruction-specific argumentation aids; Argumentieren in der Quantenphysik. Unterrichtsspezifische Argumentationshilfen

Energy Technology Data Exchange (ETDEWEB)

Friege, Gunnar; Scholz, Ruediger (eds.)

2017-07-01

In this book aids for the instruction of quantum physics are described. Especially considered are the conception of the photon, quantum interference, entanglement, the photoelectric effect, and coincidence experiments. (HSI)

Dose distribution close to metal implants in Gamma Knife Radiosurgery: A Monte Carlo study

International Nuclear Information System (INIS)

Cheung, Joel Y.C.; Yu, K.N.; Chan, Josie F.K.; Ho, Robert T.K.; Yu, C.P.

2003-01-01

Materials with high atomic numbers favor the occurrence of the photoelectric effect when they are irradiated with gamma rays. Therefore, the photoelectric effects of metal implants within the target regions in Gamma Knife Radiosurgery are worth studying. In the present work, Monte Carlo simulations using EGS4 were employed to investigate the resulting dose enhancements. A dose enhancement as high as 10% was observed close to a platinum implant along the x and y axes, while no significant dose enhancements were observed for silver, stainless steel 301, and titanium ones. A dose enhancement as high as 20% was observed close to the platinum implant along the z axis at the superior position of the metal-phantom interface and was 10% higher for other metal implants

A quantitative theory of the Hounsfield unit and its application to dual energy scanning.

Science.gov (United States)

Brooks, R A

1977-10-01

A standard definition is proposed for the Hounsfield number. Any number in computed tomography can be converted to the Hounsfield scale after performing a simple calibration using air and water. The energy dependence of the Hounsfield number, H, is given by the expression H = (Hc + Hp Q)/(1 + Q), where Hc and Hp are the Compton and photoelectric coefficients of the material being measured, expressed in Hounsfield units, and Q is the "quality factor" of the scanner. Q can be measured by performing a scan of a single calibrating material, such as a potassium iodine solution. By applying this analysis to dual energy scans, the Compton and photoelectric coefficients of an unknown substance may easily be obtained. This can lead to a limited degree of chemical identification.

Fabrication of Natural Sensitizer Extracted from Mixture of Purple Cabbage, Roselle, Wormwood and Seaweed with High Conversion Efficiency for DSSC.

Science.gov (United States)

Chang, Ho; Lai, Xuan-Rong

2016-02-01

This study aims to deal with the influence of different solvent in extraction of natural sensitizer and different thickness of photoelectrode thin film on the photoelectric conversion efficiency and the electron transport properties for the prepared dye-sensitized solar cells (DSSC). The natural dyes of anthocyanin and chlorophyll dyes are extracted from mixture of purple cabbage and roselle and mixture of wormwood and seaweed, respectively. The experimental results show the cocktail dye extracted with ethanol and rotating speed of spin coating at 1000 rpm can achieve the greatest photoelectric conversion efficiency up to 1.85%. Electrochemical impedance result shows that the effective diffusion coefficient for the prepared DSSC with the thickness of photoelectrode thin film at 21 microm are 5.23 x 10(-4) cm2/s.

Absolute dimensions and evolutionary status of UW CMa

International Nuclear Information System (INIS)

Parthasarathy, M.

1978-01-01

Photoelectric B and V light curves of close binary system UW Canis Majoris (08.5 If + O-B) are analysed. Combining the photoelectric elements and the spectroscopic orbit absolute dimensions of the system are determined. The mass of the bright primary (08.5 If) component is found to be 19.3 solar masses and that of the faint secondary to be 23.2 solar masses. The primary has filled the Roche lobe and it is 1 to 2 mag over-luminous for its mass. The massive secondary component is most likely a main sequence star. Comparison with the theoretical evolutionary models of massive close binary systems undergoing case A of mass exchange indicate that UW CMa is close to the contact stage of evolution. (author)

Hybrid system of semiconductor and photosynthetic protein

International Nuclear Information System (INIS)

Kim, Younghye; Shin, Seon Ae; Lee, Jaehun; Yang, Ki Dong; Nam, Ki Tae

2014-01-01

Photosynthetic protein has the potential to be a new attractive material for solar energy absorption and conversion. The development of semiconductor/photosynthetic protein hybrids is an example of recent progress toward efficient, clean and nanostructured photoelectric systems. In the review, two biohybrid systems interacting through different communicating methods are addressed: (1) a photosynthetic protein immobilized semiconductor electrode operating via electron transfer and (2) a hybrid of semiconductor quantum dots and photosynthetic protein operating via energy transfer. The proper selection of materials and functional and structural modification of the components and optimal conjugation between them are the main issues discussed in the review. In conclusion, we propose the direction of future biohybrid systems for solar energy conversion systems, optical biosensors and photoelectric devices. (topical reviews)

Properties of films and p-i-n photo-transformed structures on the basis of a-Si:H and its alloys, received in glow discharge of a constant current

International Nuclear Information System (INIS)

Tauasarov, K.

1997-01-01

The work devoted to investigation and control of structural, optical and photoelectric properties of films of amorphous hydrogenated silicon and its alloys, deposited in glow discharge of a constant current were done, creation of photo transformed p-i-n structures investigation its photoelectric characteristics. The main results and conclusions: A new method of deposition in glow discharge of a constant current qualitative doping and un doping a-Si:H layer and p-i-n structures on the basis of amorphous hydrogenated silicon was developed. For reception of amorphous p + and n - films for first time synthesised and applied mono-silborina and mono-silphosfin, containing pointed Si-B and Si-P linkages. New layered linear - organized structure in the films a-Si:H (T=200 deg C) was found out with distance between layers 7,5 A-o. Degree of crystallinity from combinational spectrum was determined. Concentration of films and connection between a hydrogen and silicon was determined from a IR-spectrum. It was shown that introduction of vary zone p + layer from a-Si x C 1-x :H into photo transformed p-i-n structure on the basis of a-Si:H results to decreasing of recombination losses in the area of p-i hetero boundary, and as result a photosensitive in the short-wave area of a spectrum increased. Best p-i-n structures in condition of natural illumination had following parameters: density of current of short circuit I sc =12,9 m A/cm 2 , voltage in single course U lm =0,85 V, factor of Ff.=0,55 filling and h=7% efficiency. (author)

Photometric study of the M51 system

International Nuclear Information System (INIS)

Burkhead, M.S.

1978-01-01

Photoelectric and photographic data are presented for the two components of the M51 system, NGC 5194 and NGC 5195. The photoelectric observations (UBV and I) are presented as a series of drift scans with various diaphragm sizes covering the bright central and faint outer regions. These data indicate the complexity and the very large extent of the system. Colors and magnitudes of the spiral arms are presented. The I data in particular show the broad spiral features first shown photographically by Zwicky. Deep, integrated photographic plates (IIIa-J) also show the large, structured outer regions and the complex nature of the region between the two galaxies. Calibrated contour maps and integrated luminosities of the system are presented.The maximum detected extent of the system is 40 arcmin or 120kpc. If a M/L ratio of 10 is assumed, the mass in the outer envelope is equal to the mass obtained for the more familiar bright optical components.These data and their presentation in the form of photoelectric drift scans, composite photographs, contour maps, and three-dimensional plots show the marvelous complexity of the system. It would seem that the individual galaxies, NGC 5194 and NGC 5195, cannot be considered separately but must be studied in the context of their being members of the M51 system

Photon interaction studies using 241Am γ-rays

International Nuclear Information System (INIS)

Ramachandran, N.; Karunakaran Nair, K.; Abdullah, K.K.; Varier, K.M.

2006-01-01

We have carried out some photon interaction measurements using 59.54 keV γ-rays from a 241 Am source. These include γ attenuation studies as well as photoelectric absorption studies in various samples. The attenuation studies have been made using leaf and wood samples, samples like sand, sugar etc., which contain particles of varying sizes as well as pellets and aqueous solutions of rare earth compounds. In the case of the leaf and wood samples, we have used the γ-ray attenuation technique for the determination of the water content in fresh and dried samples. The variation of the attenuation coefficient with particle size has been investigated for sand and sugar samples. The attenuation studies as well as the photoelectric studies in the case of rare earth elements have been carried out on samples containing such elements whose K-absorption edge energies lie below and close to the γ-energy used. Suitable compounds of the rare earth elements have been chosen as mixture absorbers in these investigations. A narrow beam good geometry set-up was used for the attenuation measurements. A well-shielded scattering geometry was used for the photoelectric measurements. The mixture rule was invoked to extract the values of the mass attenuation coefficients for the elements from those of the corresponding compounds. The results are consistent with theoretical values derived from the XCOM package. (author)

[Influence of MnO3 on Photoelectric Performance in Organic Light Emitting Diodes].

Science.gov (United States)

Guan, Yun-xia; Chen, Li-jia; Chen, Ping; Fu, Xiao-qiang; Niu, Lian-bin

2016-03-01

Organic Light Emitting Diodes (OLEDs) has been a promising new research point that has received much attention recently. Emission in a conventional OLED originates from the recombination of carriers (electrons and holes) that are injected from external electrodes. In the device, Electrons, on the other hand, are injected from the Al cathode to an electron-transporting layer and travel to the same emissive zone. Holes are injected from the transparent ITO anode to a hole-transporting layer and holes reach an emitting zone through the holetransporting layer. Electrons and holes recombine at the emissive film to formsinglet excited states, followed by emissive light. It is because OLED is basically an optical device and its structure consists of organic or inorganic layers of sub-wavelength thickness with different refractive indices. When the electron and holes are injected through the electrodes, they combine in the emission zone emitting the photons. These photons will have the reflection and transmission at each interface and the interference will determine the intensity profile. The emissive light reflected at the interfaces or the metallic electrode returns to the emissive layer and affects the radiation current efficiency. Microcavity OLED can produce saturated colors and narrow the emission spetrum as a new kind of technique. In the paper, we fabricate microcavity OLED using glass substrate. Ag film acts as the anode reflector mirror; NPB serves as the hole-transporting material; Alq3 is electron-transporting material and organic emissive material; Ag film acts as cathode reflector mirror. The microcavity OLED structures named as A, B, C and D are glass/Ag(15 nm)/MoO3 (x nm)/NPB(50 nm)/Alq3 (60 nm)/A1(100 nm). Here, A, x = 4 nm; B, x = 7 nm; C, x = 10 nm; D, x = 13 nm. The characteristic voltage, brightness and current of these devices are investigated in the electric field. The luminance from the Devices A, B, C and D reaches the luminance of 928, 1 369, 2

Effect of hydrogen on properties of diode structures with Pd/GaAs/InGaAs quantum wells

CERN Document Server

Karpovich, I A; Shobolov, E L; Zvonkov, B N

2002-01-01

The effect of hydrogen on the photoelectric properties and on the photoluminescence of the Pd/GaAs/InGaAs quantum well diode structures was investigated. The effect of the GaAs anodic oxide thickness on the structure parameters was found and its optimal thickness for the hydrogen sensors was determined. The essential importance of the metal bridges in the thin oxide layers for the current voltage characteristic was established. It was shown that quantum wells increase the sensitivity of the structures to hydrogen. The defect formation during the deposition of the Pd electrode on the natural and anodized GaAs surface was investigated using the quantum wells as the local defect probes. The possibility of the hydrogen passivation of the defects in the diode structures by introduction of the atomic hydrogen through the Pd electrode in a molecular hydrogen atmosphere was proved

Research progress of VO2 thin film as laser protecting material

Science.gov (United States)

Liu, Zhiwei; Lu, Yuan; Hou, Dianxin

2018-03-01

With the development of laser technology, the battlefield threat of directional laser weapons is becoming more and more serious. The blinding and destruction caused by laser weapons on the photoelectric equipment is an important part of the current photo-electronic warfare. The research on the defense technology of directional laser weapons based on the phase transition characteristics of VO2 thin films is an important subject. The researches of VO2 thin films are summarized based on review these points: the preparation methods of VO2 thin films, phase transition mechanism, phase transition temperature regulating, interaction between VO2 thin films and laser, and the application prospect of vo2 thin film as laser protecting material. This paper has some guiding significance for further research on the VO2 thin films in the field of defense directional laser weapons.

Corrections corner

Science.gov (United States)

Miller, Arthur I.; Shanklin, Jon

2015-09-01

In your otherwise informative article on “Curing the Curie complex” (Features, August pp25-28), you wrote “Albert Einstein was awarded a Nobel prize for his discovery of the photoelectric effect”.

Hot Emission-line Binaries Observed at Hvar

Czech Academy of Sciences Publication Activity Database

Božić, H.; Harmanec, P.; Koubský, Pavel

2013-01-01

Roč. 37, č. 1 (2013), s. 9-26 ISSN 1845-8319 Institutional research plan: CEZ:AV0Z10030501 Keywords : photoelectric UBV photometry * Be bineries Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

Characterizing the Lunar Particulate Atmosphere with the Autonomous Lunar Dust Observer (ALDO)

Science.gov (United States)

Grund, C. J.; Colwell, J. A.

2008-07-01

Photoelectric effects and solar wind charge the lunar surface, levitating particles. ALDO maps suspended dust in 3D using lidar. Phenomenology and instrument modeling, applications, projected performance and concepts of operation are discussed.

Three Characteristics of Effective Teachers

Science.gov (United States)

Steele, Natalie A.

2010-01-01

This article discusses three characteristics that are often associated with successful music educators. The three characteristics discussed include nonverbal communication, teacher self-efficacy, and servant leadership. Although there is no magical combination of characteristics that will produce an effective music teacher, these three attributes…

Flammability characteristics of LPG

International Nuclear Information System (INIS)

Cardillo, Paolo

2005-01-01

The use of LPG is continuous increase not only in the domestic field but also in the field of the transports. Consequently, there is a renewed interest for its flammability characteristics in order to decide the necessary conditions of safety. The main components of LPG are hydrocarbons containing three or four carbon atoms. The normal components of LPG are propane and butane; small concentrations of other hydrocarbons (isobutene, propylene, butane, ethane, pentane) may also be present. Different mixtures of LGP have different and physical characteristics with a different behavior during the use. Also flammability characteristics can be different according to the composition. In this paper at firsts the flammability characteristics of the main components of LGP, taken singularly, are examinated; subsequently some examples of calculation of the flammability limits of different mixture are reported [it

The characteristics of a pneumatic muscle

Directory of Open Access Journals (Sweden)

Pietrala Dawid

2017-01-01

Full Text Available The article presents static and dynamic characteristics of pneumatic muscles. It presents the structure of the laboratory stand used to test pneumatic muscles. It discusses the methodology for determination of static and dynamic characteristics. The paper also illustrates characteristics showing the relationship of pneumatic muscles length and operating pressure, at a constant loading force (isotonic characteristics. It presents characteristics showing the relationship of pneumatic muscles shortening and values of loading forces, at a constant operational pressure (isobaric characteristics. It also shows the dependence of force generated by the muscle on the operating pressure, at a constant value of pneumatic muscles shortening (isometric characteristics. The paper also presents dynamic characteristics of a pneumatic muscle showing the response of an object to a gradual change in the operating pressure, at a constant loading force acting on the pneumatic muscle.

The characteristics of a pneumatic muscle

Science.gov (United States)

Pietrala, Dawid

The article presents static and dynamic characteristics of pneumatic muscles. It presents the structure of the laboratory stand used to test pneumatic muscles. It discusses the methodology for determination of static and dynamic characteristics. The paper also illustrates characteristics showing the relationship of pneumatic muscles length and operating pressure, at a constant loading force (isotonic characteristics). It presents characteristics showing the relationship of pneumatic muscles shortening and values of loading forces, at a constant operational pressure (isobaric characteristics). It also shows the dependence of force generated by the muscle on the operating pressure, at a constant value of pneumatic muscles shortening (isometric characteristics). The paper also presents dynamic characteristics of a pneumatic muscle showing the response of an object to a gradual change in the operating pressure, at a constant loading force acting on the pneumatic muscle.

The characteristics of a pneumatic muscle

OpenAIRE

Pietrala Dawid

2017-01-01

The article presents static and dynamic characteristics of pneumatic muscles. It presents the structure of the laboratory stand used to test pneumatic muscles. It discusses the methodology for determination of static and dynamic characteristics. The paper also illustrates characteristics showing the relationship of pneumatic muscles length and operating pressure, at a constant loading force (isotonic characteristics). It presents characteristics showing the relationship of pneumatic muscles s...

General Space-Confined On-Substrate Fabrication of Thickness-Adjustable Hybrid Perovskite Single-Crystalline Thin Films.

Science.gov (United States)

Chen, Yao-Xuan; Ge, Qian-Qing; Shi, Yang; Liu, Jie; Xue, Ding-Jiang; Ma, Jing-Yuan; Ding, Jie; Yan, Hui-Juan; Hu, Jin-Song; Wan, Li-Jun

2016-12-21

Organic-inorganic hybrid perovskite single-crystalline thin films (SCTFs) are promising for enhancing photoelectric device performance due to high carrier mobility, long diffusion length, and carrier lifetime. However, bulk perovskite single crystals available today are not suitable for practical device application due to the unfavorable thickness. Herein, we report a facile space-confined solution-processed strategy to on-substrate grow various hybrid perovskite SCTFs in a size of submillimeter with adjustable thicknesses from nano- to micrometers. These SCTFs exhibit photoelectric properties comparable to bulk single crystals with low defect density and good air stability. The clear thickness-dependent colors allow fast visual selection of SCTFs with a suitable thickness for specific device application. The present substrate-independent growth of perovskite SCTFs opens up opportunities for on-chip fabrication of diverse high-performance devices.

Performance Maintenance of Dye-Sensitized Solar Cells Using a Latent Heat Storage Material

Science.gov (United States)

Haruki, Naoto; Horibe, Akihiko

2017-07-01

Recently, there has been considerable interest in various renewable energies. Among them, solar cell production has increased markedly because the photovoltaic is a clean and safe power generation method. The dye-sensitized solar cell (DSSC) has attracted much attention as an alternative to silicon solar cells due to lower manufacturing costs and plentiful resources for DSSC production. However, the performance of DSSCs has been limited by their durability and low photoelectric conversion efficiency. Temperature control of DSSCs via phase-change materials (PCMs) is expected to improve performance. In this study, DSSCs were heated or cooled with a heat exchanger copper block that was in contact with a PCM (heptadecane), while being irradiated by a solar simulator light source. The durability and photoelectric conversion efficiency of the DSSC improved under PCM temperature control.

Apparent luminosity function of galaxies to the twenty-first magnitude

International Nuclear Information System (INIS)

Brown, G.S.

1979-01-01

Galaxy counts to limiting magnitudes B=17.7 to 21.0 in 13 selected areas in the north galactic polar cap are presented. The photographs were taken with a reducing camera at the Cassegrain focus of the 91 cm and 205 cm reflectors of McDonald Observatory. Both galaxy and star images were counted and recorded. On each plate a few stars and galaxies were marked as representative of the plate limit. Selected brighter galaxies and stars were measured photoelectrically to fix the zero points. The B magnitude limits of each plate for stars and galaxies are obtained by a combination of photoelectric and photographic photometry. The resulting apparent luminosity functions of galaxies and stars are compared with earlier data. Sources of error in the counts are discussed in detail

X-ray dosimetry of TlGaSe2 single crystals

International Nuclear Information System (INIS)

Kerimova, E.M.; Mustafaeva, S.N.; Mamedbeili, S.D.; Jabarov, J.N.; Iskenderova, P.M.; Kazimov, S.B.

2002-01-01

TlGaSe 2 compound belongs to group of layered semiconductors of A 3 B 3 C 2 6 -type. Photoelectric and optical properties of TlGaSe 2 single crystals were investigated in detail. Influence of gamma-, electron and neutron radiation on photoelectric properties of TlGaSe 2 single crystals is investigated too. The present work deals with experimental results relative to X-ray dosimetric characteristics of TlGaSe 2 crystals at 300 K. X-ray conductivity and X-ray dosimetric characteristic measurements are carried out in low load resistance regime. The source of X-ray radiation is the installation of X-ray diffraction analysis (URS-55a) with the BCV-2(Cu). Intensity of X-ray radiation (E) is regulated by measurement with current variation in tube at each given value of X-ray radiation dose E (R/min) are measured by crystal dosimeter DRGZ-02. X-ray conductivity coefficients K σ characterising X-ray sensitivity of investigated crystals are determined as the relative change of conductivity under X-ray radiation a per dose. There have been determined values of characteristic coefficients of TlGaSe 2 single crystal X-ray conductivity at different values of accelerating voltage (V a ) on the tube and corresponding doses of X-ray radiation. Analysis of obtained data showed that X-ray conductivity coefficients K σ in studied crystals are regularly decreased (from 0.276 to 0.033) as with the rise of dose (E=0.75-78.0 R/min) as with the increase of values of V a on X-ray tube (V a =254-50 keV). One of the possible reasons of observed regularities is that X-ray conductivity in investigated crystals, especially at comparatively low V a is due predominantly to radiation of thin layer of crystal. In this case with the rise of radiation intensity there have been started to prevail the mechanism of surface quadratic recombination which leads to observed decrease of X-ray conductivity. With the rise of accelerating potential 'effective hardness' is increased, as a result of which there

14 CFR 29.239 - Spray characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Spray characteristics. 29.239 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Ground and Water Handling Characteristics § 29.239 Spray characteristics. If certification for water operation is requested, no spray characteristics...

14 CFR 27.239 - Spray characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Spray characteristics. 27.239 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Flight Ground and Water Handling Characteristics § 27.239 Spray characteristics. If certification for water operation is requested, no spray characteristics...

Photoelectric Radial Velocities, Paper XVIII Spectroscopic Orbits for ...

Indian Academy of Sciences (India)

The fundamental origin of the work presented here rests with the radial-velocity spectrometer that .... surfaces inevitably degrade rather rapidly in the environment in which they are called ...... are not safe to incorporate in the data set here.

Characteristics of a Healthy Family.

Science.gov (United States)

Lin, Phylis Lan

The reason for studying the characteristics of a healthy family is to encourage and strengthen the family and to move toward an enriched family life by using the characteristics as bench marks. Six characteristics are discussed as the essence of a healthy family: (1) commitment; (2) togetherness; (3) appreciation; (4) good communication; (5)…

Characteristics of early psychosis

NARCIS (Netherlands)

Schothorst, P.F.; Emck, C.; van Engeland, H.

2006-01-01

There is little research on characteristics related to course and prognosis of early-onset psychosis. The present article aims to advance our knowledge of this disorder for the purpose of proper diagnosis and treatment. It focuses on premorbid and prodromal characteristics, treatment history,

Characteristics of Successful Entrepreneurs.

Science.gov (United States)

McClelland, David C.

1987-01-01

Comparison of characteristics of 12 average and 12 superior small business people in three developing nations (India, Malawi, and Ecuador) found proactive qualities such as initiative and assertiveness, achievement orientation, and commitment to others characteristic of successful entrepreneurs. Other expected qualities (self-confidence,…

Plasticity characteristic obtained by indentation

International Nuclear Information System (INIS)

Mil'man, Yu.V.; Chugunova, S.I.; Goncharova, I.V.

2011-01-01

Methods for determination plasticity characteristic δH in the measurement of hardness and nanohardness are considered. Parameter δH characterizes the plasticity of a material by the part of plastic deformation in the total elastic-plastic deformation. The value of δH is defined for metals with different types of crystal lattice, covalent and partially covalent crystals, intermetallics, metallic glasses and quasicrystals. It is discussed the dependence of the plasticity characteristic δH on structural factors and temperature. Parameter δH allows to analyze and compare the plasticity of materials which are brittle at standard mechanical tests. The combination of hardness H, as the strength characteristic, and the plasticity characteristic δH makes possible the better characterization of mechanical behavior of materials than only the hardness H. The examples of plasticity characteristic δH application are represented.

TRIGA reactor characteristics

International Nuclear Information System (INIS)

Boeck, H.; Villa, M.

2007-01-01

This module describes the general design, characteristics and parameters of TRIGA reactors and fuels. It is recommended that most of this information should be incorporated into any reactor operator training program and, in many cases, the facility Safety Analysis Report. It is oriented to teach the basics of the physics and mechanical design of the TRIGA fuel as well as its unique operational characteristics and the differences between TRIGA fuels and others more traditional reactor fuels. (nevyjel)

Optical extensometer

Science.gov (United States)

Walker, Ray A.; Reich, Fred R.; Russell, James T.

1978-01-01

An optical extensometer is described using sequentially pulsed light beams for measuring the dimensions of objects by detecting two opposite edges of the object without contacting the object. The light beams may be of different distinguishable light characteristics, such as polarization or wave length, and are time modulated in an alternating manner at a reference frequency. The light characteristics are of substantially the same total light energy and are distributed symmetrically. In the preferred embodiment two light beam segments of one characteristic are on opposite sides of a middle segment of another characteristic. As a result, when the beam segments are scanned sequentially across two opposite edges of the object, they produce a readout signal at the output of a photoelectric detector that is compared with the reference signal by a phase comparator to produce a measurement signal with a binary level transition when the light beams cross an edge. The light beams may be of different cross sectional geometries, including two superimposed and concentric circular beam cross sections of different diameter, or two rectangular cross sections which intersect with each other substantially perpendicular so only their central portions are superimposed. Alternately, a row of three light beams can be used including two outer beams on opposite sides and separate from a middle beam. The three beams may all be of the same light characteristic. However it is preferable that the middle beam be of a different characteristic but of the same total energy as the two outer beams.

THE COMBUSTION CHARACTERISTICS OF LIGNITE BLENDS

Institute of Scientific and Technical Information of China (English)

Cheng Jun; Zhou Junhu; Cao Xinyu; Cen Kefa

2000-01-01

The combustion characteristics of lignite blends were studied with a thermogravimetric analyzer (t.g.a.), at constant heating rate.The characteristic temperatures were determined from the burning profiles.It was found that the characteristic times of combustion reaction moved forward, the ignition temperature dropped and the burnout efficiency slightly changed when blending lignites.The characteristic parameters of blends could not be predicted as a linear function of the average values of the individual lignites.when blending with less reactive coal, the ignition and burnout characteristics of lignite turned worse.

Fracture characteristics in Japanese rock

International Nuclear Information System (INIS)

Ijiri, Yuji; Sawada, Atsushi; Akahori, Kuniaki

1999-11-01

It is crucial for the performance assessment of geosphere to evaluate the characteristics of fractures that can be dominant radionuclide migration pathways from a repository to biosphere. This report summarizes the characteristics of fractures obtained from broad literature surveys and the fields surveys at the Kamaishi mine in northern Japan and at outcrops and galleries throughout the country. The characteristics of fractures described in this report are fracture orientation, fracture shape, fracture frequency, fracture distribution in space, transmissivity of fracture, fracture aperture, fracture fillings, alteration halo along fracture, flow-wetted surface area in fracture, and the correlation among these characteristics. Since granitic rock is considered the archetype fractured media, a large amount of fracture data is available in literature. In addition, granitic rock has been treated as a potential host rock in many overseas programs, and has JNC performed a number of field observations and experiments in granodiorite at the Kamaishi mine. Therefore, the characteristics of fractures in granitic rock are qualitatively and quantitatively clarified to some extent in this report, while the characteristics of fractures in another rock types are not clarified. (author)

Photon interaction studies using 241Am γ-rays

Indian Academy of Sciences (India)

rays from a 241Am source. These include attenuation studies as well as photoelectric absorption studies in various samples. The attenuation studies have been made using leaf and wood samples, samples like sand, sugar etc., which ...

Housing characteristics 1993

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-06-01

This report, Housing Characteristics 1993, presents statistics about the energy-related characteristics of US households. These data were collected in the 1993 Residential Energy Consumption Survey (RECS) -- the ninth in a series of nationwide energy consumption surveys conducted since 1978 by the Energy Information Administration of the US Department of Energy. Over 7 thousand households were surveyed, representing 97 million households nationwide. A second report, to be released in late 1995, will present statistics on residential energy consumption and expenditures.

14 CFR 25.253 - High-speed characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false High-speed characteristics. 25.253 Section...-speed characteristics. (a) Speed increase and recovery characteristics. The following speed increase and recovery characteristics must be met: (1) Operating conditions and characteristics likely to cause...

Effective atomic numbers of some tissue substitutes by different methods: A comparative study

Directory of Open Access Journals (Sweden)

Vishwanath P Singh

2014-01-01

Full Text Available Effective atomic numbers of some human organ tissue substitutes such as polyethylene terephthalate, red articulation wax, paraffin 1, paraffin 2, bolus, pitch, polyphenylene sulfide, polysulfone, polyvinylchloride, and modeling clay have been calculated by four different methods like Auto-Z eff, direct, interpolation, and power law. It was found that the effective atomic numbers computed by Auto-Z eff , direct and interpolation methods were in good agreement for intermediate energy region (0.1 MeV < E < 5 MeV where the Compton interaction dominates. A large difference in effective atomic numbers by direct method and Auto-Z eff was observed in photo-electric and pair-production regions. Effective atomic numbers computed by power law were found to be close to direct method in photo-electric absorption region. The Auto-Z eff , direct and interpolation methods were found to be in good agreement for computation of effective atomic numbers in intermediate energy region (100 keV < E < 10 MeV. The direct method was found to be appropriate method for computation of effective atomic numbers in photo-electric region (10 keV < E < 100 keV. The tissue equivalence of the tissue substitutes is possible to represent by any method for computation of effective atomic number mentioned in the present study. An accurate estimation of Rayleigh scattering is required to eliminate effect of molecular, chemical, or crystalline environment of the atom for estimation of gamma interaction parameters.

Multichannel photocells for image converters with color separation

Energy Technology Data Exchange (ETDEWEB)

Denisova, E. A.; Uzdovskii, V. V., E-mail: uzdovskii@list.ru; Khainovskii, V. I. [Moscow Institute of Electronic Technology (Russian Federation)

2011-12-15

The results of a study of photoelectric processes in photosensitive structures based on a multichannel vertically integrated p-n junction are presented. Optical radiation absorption in the space-charge region of a multichannel vertically integrated structure is studied.

Photoinduced conductivity in mycosporine-like amino acids

International Nuclear Information System (INIS)

Kulkarni, Atul; Lee, Jeong Hun; Seo, Hyo Hyun; Kim, Hyoung-Shik; Cho, Moon Jin; Shin, Dong Sun; Kim, Taesung; Moh, Sang Hyun

2015-01-01

Mycosporine-like amino acids (MAAs) are an important group of novel bioactive compounds having immense biotechnological potentials due to their UV screening properties and antioxidant activities. However, their photoelectric properties were not evaluated yet. In the present work two types of MAAs Shinorine and Porphyra-334, were extracted from algae; Chlamydomonas hedlyei and Porphyra yezoensis respectively and its electrical transport properties were investigated upon illumination of UV light. The combination of optical absorption and electron transport measurement of MAAs in a field effect transistor device reveals that these changes are mainly due to the carboxyl group present in MAAs. This study reports a platform technology for the development of novel biochemical–electrical devices. - Highlights: • MAAs FET shows photoelectric effect upon UV illumination. • Enhancement in photo conductance is due to the hydroxyl ethyl group. • Potential as bio-opto-electrical devices applications

Electric field-induced resistive switching, magnetism, and photoresponse modulation in a Pt/Co0.03Zn0.97O/Nb:SrTiO3 multi-function heterostructure

Science.gov (United States)

Luo, Zhipeng; Pei, Ling; Li, Meiya; Zhu, Yongdan; Xie, Shuai; Cheng, Xiangyang; Liu, Jiaxian; Ding, Huaqi; Xiong, Rui

2018-04-01

A Co0.03Zn0.97O (CZO) thin film was epitaxially grown on a Nb doped (001) SrTiO3 (NSTO) single-crystal substrate by pulsed laser deposition to form a Pt/CZO/NSTO heterostructure. This device exhibits stable bipolar resistive switching, well retention and endurance, multilevel memories, and a resistance ratio of high resistance state (HRS)/low resistance state (LRS) up to 7 × 105. Under the illumination of a 405 nm laser, the HRS of the device showed distinct photoelectricity with an open-circuit voltage of 0.5 V. A stronger ferromagnetism was observed at the HRS than at the LRS. The above phenomenon is attributable to the accumulation and migration of oxygen vacancies at the interface of CZO/NSTO. Our results demonstrated a pathway towards making multifunctional devices that simultaneously exhibit resistive switching, photoelectricity, and ferromagnetism.

Laboratory Investigations of the Physical and Optical Properties of the Analogs of Individual Cosmic Dust Grains

Science.gov (United States)

Abbas, M. M.; Tankosic, D.; Craven, P. D.; Spann, J. F.; LeClair, A.; West, E. A.

2005-01-01

Microdsub-micron size cosmic dust grains play an important role in the physical and dynamical process in the galaxy, the interstellar medium, and the interplanetary and planetary environments. The dust grains in various astrophysical environments are generally charged by a variety of mechanisms that include collisional process with electrons and ions, and photoelectric emissions with UV radiation. The photoelectric emission process is believed to be the dominant process in many astrophysical environments with nearby UV sources, such as the interstellar medium, diffuse clouds, the outer regions of the dense molecular clouds, interplanetary medium, dust in planetary environments and rings, cometary tails, etc. Also, the processes and mechanisms involved in the rotation and alignment of interstellar dust grains are of great interest in view of the polarization of observed starlight as a probe for evaluation of the galactic magnetic field.

Nonlinear optical properties of systems based on ruthenium(II) tetra-15-crown-5-phthalocyaninate

International Nuclear Information System (INIS)

Grishina, A.D.; Gorbunova, Yu.G.; Enakieva, Yu.Yu.; Krivenko, T.V.; Savel'ev, V.V.; Vannikov, A.V.; Tsivadze, A.Yu.

2008-01-01

The third-order nonlinear optical properties of the ruthenium (II) complex with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules (R 4 Pc)Ru(TED) 2 were analyzed by means of the z-scanning technique. A solution of (R 4 Pc)Ru(TED) 2 in tetrachloroethane was exposed to nanosecond laser pulses at a wavelength of 1064 nm. It was found that the third-order molecular polarizability of the Ru(II) complex is 4.5 x 10 -32 cm 4 /C (esu). The polarizability per molecule increases by a factor of 3.6 when the single molecule occurs in a supramolecular assembly of (R 4 Pc)Ru(TED) 2 complexes. The photoelectric and photorefractive properties at 1064 nm of polymer composites, determined by the supramolecular assemblies that exhibits optical absorption and photoelectric sensitivity in the near IR region, are reported [ru

A Robust Distributed Multipoint Fiber Optic Gas Sensor System Based on AGC Amplifier Structure.

Science.gov (United States)

Zhu, Cunguang; Wang, Rende; Tao, Xuechen; Wang, Guangwei; Wang, Pengpeng

2016-07-28

A harsh environment-oriented distributed multipoint fiber optic gas sensor system realized by automatic gain control (AGC) technology is proposed. To improve the photoelectric signal reliability, the electronic variable gain can be modified in real time by an AGC closed-loop feedback structure to compensate for optical transmission loss which is caused by the fiber bend loss or other reasons. The deviation of the system based on AGC structure is below 4.02% when photoelectric signal decays due to fiber bending loss for bending radius of 5 mm, which is 20 times lower than the ordinary differential system. In addition, the AGC circuit with the same electric parameters can keep the baseline intensity of signals in different channels of the distributed multipoint sensor system at the same level. This avoids repetitive calibrations and streamlines the installation process.

Photoinduced conductivity in mycosporine-like amino acids

Energy Technology Data Exchange (ETDEWEB)

Kulkarni, Atul; Lee, Jeong Hun; Seo, Hyo Hyun; Kim, Hyoung-Shik; Cho, Moon Jin; Shin, Dong Sun [Antiaging Research Institute of BIO-FD and C Co. Ltd., Incheon 406-840 (Korea, Republic of); Kim, Taesung [Sungkyunkwan Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Moh, Sang Hyun, E-mail: shmoh@biofdnc.com [Antiaging Research Institute of BIO-FD and C Co. Ltd., Incheon 406-840 (Korea, Republic of)

2015-02-01

Mycosporine-like amino acids (MAAs) are an important group of novel bioactive compounds having immense biotechnological potentials due to their UV screening properties and antioxidant activities. However, their photoelectric properties were not evaluated yet. In the present work two types of MAAs Shinorine and Porphyra-334, were extracted from algae; Chlamydomonas hedlyei and Porphyra yezoensis respectively and its electrical transport properties were investigated upon illumination of UV light. The combination of optical absorption and electron transport measurement of MAAs in a field effect transistor device reveals that these changes are mainly due to the carboxyl group present in MAAs. This study reports a platform technology for the development of novel biochemical–electrical devices. - Highlights: • MAAs FET shows photoelectric effect upon UV illumination. • Enhancement in photo conductance is due to the hydroxyl ethyl group. • Potential as bio-opto-electrical devices applications.

THERMODYNAMICS AND CHARGING OF INTERSTELLAR IRON NANOPARTICLES

Energy Technology Data Exchange (ETDEWEB)

Hensley, Brandon S. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Draine, B. T., E-mail: brandon.s.hensley@jpl.nasa.gov [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

2017-01-10

Interstellar iron in the form of metallic iron nanoparticles may constitute a component of the interstellar dust. We compute the stability of iron nanoparticles to sublimation in the interstellar radiation field, finding that iron clusters can persist down to a radius of ≃4.5 Å, and perhaps smaller. We employ laboratory data on small iron clusters to compute the photoelectric yields as a function of grain size and the resulting grain charge distribution in various interstellar environments, finding that iron nanoparticles can acquire negative charges, particularly in regions with high gas temperatures and ionization fractions. If ≳10% of the interstellar iron is in the form of ultrasmall iron clusters, the photoelectric heating rate from dust may be increased by up to tens of percent relative to dust models with only carbonaceous and silicate grains.

US photovoltaic patents: 1991--1993

Energy Technology Data Exchange (ETDEWEB)

Pohle, L

1995-03-01

This document contains US patents on terrestrial photovoltaic (PV) power applications, including systems, components, and materials as well as manufacturing and support functions. The patent entries in this document were issued from 1991 to 1993. The entries were located by searching USPA, the database of the US Patent Office. The final search retrieved all patents under the class ``Batteries, Thermoelectric and Photoelectric`` and the subclasses ``Photoelectric,`` ``Testing,`` and ``Applications.`` The search also located patents that contained the words ``photovoltaic(s)`` or ``solar cell(s)`` and their derivatives. After the initial list was compiled, most of the patents on the following subjects were excluded: space photovoltaic technology, use of the photovoltaic effect for detectors, and subjects only peripherally concerned with photovoltaic. Some patents on these three subjects were included when ft appeared that those inventions might be of use in terrestrial PV power technologies.

Photometric intensity and polarization measurements of the solar corona.

Science.gov (United States)

Mcdougal, D. S.

1971-01-01

Use of a satellite photometric observatory (SPO) to measure the solar corona from Miahuatlan, Mexico during the Mar. 7, 1970, total eclipse of the sun. The SPO is equipped with a 24-in. Cassegrainian telescope, a four-channel photoelectric photometer, a Wollaston prism, and a rotating half-wave plate. Simultaneous measurements were made of the two orthogonal components of coronal light in the B and R bands of the UBVRI system. A 1-minute arc aperture was scanned from the lunar disk center out to five solar radii in a series of spirals of gradually increasing radius. For the first time, simultaneous multicolor intensity, degree, and angle of polarization profiles are computed from photoelectric measurements. Comparison of the variations of the measurements for each spiral scan yield a detailed picture of the intensity and polarization features in the K corona.

GaN heterostructures for biosensing and radiation detection

Energy Technology Data Exchange (ETDEWEB)

Howgate, John D.

2012-12-11

In this thesis I show the results from our investigation of the interface between gallium nitride wide bandgap semiconductor heterostructures and (bio)molecular systems on their surfaces for biosensing, bioelectronics, and photoelectric applications, with a large emphasis on the processes arising from high energy ionizing irradiation, including heterostructure photoelectric gain mechanisms. Wide bandgap semiconductors, such as gallium nitride, have received increasing attention as potential components in advanced organic/inorganic hybrid systems. Working to further this topic, we determine a new semiconductor alignment required for low energy photo-induced charge transfer ionization of alkyl chains well below the energy normally required for molecular cleavage, show original results of the influence of binding methods on enzyme functionality in conjunction with a novel electrochemical and environmental control system and demonstrate new possibilities to significantly improve upon pH measurements through the use of high sensitivity devices. Furthermore, based on the extension of this work to support future studies of radiation effects on cell systems, we present a detailed characterization of new simultaneous chemical sensing and ionizing radiation dosimetry using single devices. We found that their pH sensitivity was retained during X-ray irradiation and that the fundamental characteristics can be used to separate the irradiation signal from the pH response without compromising operational stability. These data provide clear indications of the separate response mechanism tied to the presence of a two-dimensional electron gas channel. Here, we found new results exhibiting exceptionally high gains and independence of the well-known persistent photoconductivity for soft X-rays and high energy particles in the ultralow dose-rate regime. This material system provides the capability for high sensitivity and resolution real time monitoring, which is competitive with and

Highly lead-loaded red plastic scintillators as an X-ray imaging system for the laser Mega Joule

International Nuclear Information System (INIS)

Hamel, Matthieu; Normand, Stephane; Turk, Gregory; Darbon, Stephane

2012-01-01

The scope of this project intends to record spatially resolved images of core shape and size of a deuterium-tritium micro-balloon during inertial confinement fusion (ICF) experiments at Laser Mega Joule facility (LMJ). We need to develop an x-ray imaging system which can operate in the hard radiative background generated by an ignition shot of ICF. The scintillator is a part of the imaging system and has to gather a compromise of scintillating properties (scintillating efficiency, decay time, emission wavelength) so as to both operate in the hard radiative environment and to allow the acquisition of spatially resolved images. Inorganic scintillators cannot be used because no compromise can be found regarding the expected scintillating properties. Most of them are not fast enough and emit blue light. Organic scintillators are generally fast, but present low x-ray photoelectric absorption in the 10 to 40 keV range. This does not enable the acquisition of spatially resolved images. To this aim, we have developed highly lead-loaded and red-fluorescent fast plastic scintillators. Such a combination is not currently available via scintillator suppliers, since they propose only blue-fluorescent plastic scintillators doped with up to 12 wt% Pb. Thus, incorporation ratio up to 27 wt% Pb has been reached in our laboratory, which can afford a plastic scintillator with an outstanding Z(eff) close to 50. X-rays in the 10 to 40 keV range can thus interact with a higher probability of photoelectric effect than for classic organic scintillators, such as NE-102. The strong orange-red fluorescence can be filtered, so that we can eliminate residual Cerenkov light, generated by gamma-ray absorption in glass parts of the imaging system. Characteristic decay times of our scintillators evaluated under UV excitation were estimated to be in the range 10 to 13 ns. (authors)

Optical timing receiver for the NASA Spaceborne Ranging System. Part I. Dual peak-sensing timing discriminator

International Nuclear Information System (INIS)

Leskovar, B.; Lo, C.C.; Zizka, G.

1978-01-01

Position-resolution capabilities of the NASA Spaceborne Laser Ranging System are essentially determined by the time-resolution capabilities of its optical timing receiver. The optical timing receiver consists of a fast photoelectric device; (e.g., photomultiplier or an avalanche photodiode detector), a timing discriminator, a high-precision event-timing digitizer, and a signal-processing system. The time-resolution capabilities of the receiver are determined by the photoelectron time spread of the photoelectric device, the time walk and resolution characteristics of the timing discriminator, and the resolution of the event-timing digitizer. It is thus necessary to evaluate available fast photoelectronic devices with respect to their time-resolution capabilities, to design a very low time walk timing discriminator and to develop a high-resolution event-timing digitizer which will be used in the high-resolution spaceborne laser ranging system receiver. The development of a new dual-peak sensing timing discriminator is described. The amplitude dependent time walk is less than +-150 psec for a 100:1 dynamic range of Gaussian-shaped input signals having pulse widths between 11 and 17 nsec. The unit produces 800 mV negative output pulses, each 10 nsec wide, and 3V positive pulses with widths of 15 nsec. The time delay through the discriminator is approximately 37 nsec. In this discriminator the input signal is processed by a peak-crossing circuit which produces a bipolar pulse having its zero-crossing point at the peak of the input signal. All essential functions in the discriminator are performed by means of tunnel diodes with backward diodes as nonlinear loads. The discriminator is designed to be CAMAC compatible to a conventional time-interval unit or a high-precision event timing digitizer. The adjustment procedure for obtaining minimum time walk is also given

GaN heterostructures for biosensing and radiation detection

International Nuclear Information System (INIS)

Howgate, John D.

2012-01-01

In this thesis I show the results from our investigation of the interface between gallium nitride wide bandgap semiconductor heterostructures and (bio)molecular systems on their surfaces for biosensing, bioelectronics, and photoelectric applications, with a large emphasis on the processes arising from high energy ionizing irradiation, including heterostructure photoelectric gain mechanisms. Wide bandgap semiconductors, such as gallium nitride, have received increasing attention as potential components in advanced organic/inorganic hybrid systems. Working to further this topic, we determine a new semiconductor alignment required for low energy photo-induced charge transfer ionization of alkyl chains well below the energy normally required for molecular cleavage, show original results of the influence of binding methods on enzyme functionality in conjunction with a novel electrochemical and environmental control system and demonstrate new possibilities to significantly improve upon pH measurements through the use of high sensitivity devices. Furthermore, based on the extension of this work to support future studies of radiation effects on cell systems, we present a detailed characterization of new simultaneous chemical sensing and ionizing radiation dosimetry using single devices. We found that their pH sensitivity was retained during X-ray irradiation and that the fundamental characteristics can be used to separate the irradiation signal from the pH response without compromising operational stability. These data provide clear indications of the separate response mechanism tied to the presence of a two-dimensional electron gas channel. Here, we found new results exhibiting exceptionally high gains and independence of the well-known persistent photoconductivity for soft X-rays and high energy particles in the ultralow dose-rate regime. This material system provides the capability for high sensitivity and resolution real time monitoring, which is competitive with and

Airfoil characteristics for wind turbines

Energy Technology Data Exchange (ETDEWEB)

Bak, C; Fuglsang, P; Soerensen, N N; Aagaard Madsen, H [Risoe National Lab., Roskilde (Denmark); Shen, Wen Zhong; Noerkaer Soerensen, J [Technical Univ. of Denmark, Lyngby (Denmark)

1999-03-01

Airfoil characteristics for use in the Blade Element Momentum (BEM) method calculating the forces on Horizontal Axis Wind Turbines (HAWT) are derived by use of systematic methods. The investigation and derivation of the airfoil characteristics are based on four different methods: 1) Inverse momentum theory, 2) Actuator disc theory, 3) Numerical optimisation and 4) Quasi-3D CFD computations. The two former methods are based on 3D CFD computations and wind tunnel measurements on a 41-m full-scale rotor with LM 19.1 blades. The derived airfoil characteristics show that the lift coefficient in stall at the tip is low and that it is high at the root compared to 2D airfoil characteristics. The use of these characteristics in aeroelastic calculations shows a good agreement in power and flap moments with measurements. Furthermore, a fatigue analysis shows a reduction in the loads of up to 15 % compared to a commonly used set of airfoil characteristics. The numerical optimisation is based on both the 3D CFD computations and measurements on a 41-m rotor with LM 19.1 and LM 19.0 blades, respectively. The method requires power and loads from a turbine and is promising since a set of lift and drag curves is derived that can be used to calculate mean values of power and loads. The lift in stall at the tip is low and at the root it is high compared to 2D airfoil characteristics. In particular the power curves were well calculated by use of the optimised airfoil characteristics. In the quasi-3D CFD computations, the airfoil characteristics are derived directly. This Navier-Stokes model takes into account rotational and 3D effects. The model enables the study of the rotational effect of a rotor blade at computing costs similar to what is typical for 2D airfoil calculations. The depicted results show that the model is capable of determining the correct qualitative behaviour for airfoils subject to rotation. The method shows that lift is high at the root compared to 2D airfoil

An angular selective electron gun for the KATRIN experiment

Energy Technology Data Exchange (ETDEWEB)

Zacher, Michael; Ortjohann, Hans-Werner; Steinbrink, Nicholas; Josten, Lorenz; Hannen, Volker; Weinheimer, Christian; Winzen, Daniel [Westfaelische Wilhelms-Universitaet, Muenster (Germany); Collaboration: KATRIN-Collaboration

2013-07-01

The KArlsruhe TRItium Neutrino experiment aims for a measurement of the electron anti-neutrino mass with a sensitivity of 200 meV/c{sup 2} (95% C.L.) by analysing the endpoint region of the tritium β-decay. The main spectrometer (MAC-E filter type, 23m length) is one of the central parts of the experiment, featuring an energy resolution of Δ E<1 eV. For commissioning of the spectrometer a well defined electron source is needed that allows to determine the transmission characteristics and compare the electromagnetic properties to simulations. For this purpose an angular selective electron gun was developed. A pulsed UV-Laser produces electrons via the photo-electric effect, which are then accelerated electrostatically in a magnetic field. It features a small energy spread, a sharp selectable emission angle and covers the whole magnetic flux tube of KATRIN. By that, the characteristics of the spectrometer can be investigated with high precision. The time structure of the electron pulses allows time of flight measurements, offering enhanced sensitivity. The talk gives an overview about the e-gun design and its properties.

Optimal series-parallel connection method of dye-sensitized solar cell for Pt thin film deposition using a radio frequency sputter system

Energy Technology Data Exchange (ETDEWEB)

Choi, Jin-Young; Hong, Ji-Tae; Seo, Hyunwoong; Kim, Mijeong; Son, Min-Kyu; Lee, Kyoung-Jun [Department of Electrical Engineering, Pusan National University Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Lee, Dong-Yoon [Advanced Materials and Application research Laboratory, Korea Electrotechnology Research Institute, 28-1, Seongju-dong, Changwon-city, Kyongnam, 641-120 (Korea, Republic of); Kim, Hee-Je [Department of Electrical Engineering, Pusan National University Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of)], E-mail: heeje@pusan.ac.kr

2008-11-28

The counter electrode widely used in DSC (Dye-sensitized solar cells) is constructed of a conducting glass substrate coated with a Pt film, in which the platinum acts as a catalyst. The characteristics of the platinum electrode depend strongly on the fabrication process and the electrode's surface condition. In this study, Pt counter electrodes were deposited by radio frequency (RF) sputtering with 6.7 x 10{sup -1} Pa Ar, RF power of 120 W and substrate temperature of 100 deg. C . The surface morphology of Pt electrodes was investigated using field emission scanning electron microscopy and atomic force microscopy. Comparison of samples prepared by RF sputtering and RF magnetron sputtering showed that the surface of the RF sputter deposited electrode had a larger surface area resulting in more effective catalytic characteristics. Finally, an open voltage of 4.8 V, a short circuit current of 569 mA and a photoelectric conversion efficiency of approximately 3.6% were achieved for cells composed of 30 DSC units of 6 cm x 4 cm DSC units with 6 cells in series and 5 cells in parallel.

Conductive subtract development without corrosion for photovoltaic applications on porcelain stoneware according to free electrodes process

International Nuclear Information System (INIS)

Reyes-Tolosa, M. D.; Al Aajmi, M.; Orozco-Messana, J.; Donderis, V.; Pascual, M.; Hernandez-Fenollosa, M. A.

2010-01-01

In the incipient world of functional industrial ceramics with photovoltaic applications, there is a need to reduce production costs while maximizing the systems useful life. The thin contact layers currently being manufactured are based on vacuum systems with high production costs and major problems of accelerated corrosion in photovoltaic applications. The electroless process produces very even and compact layers with very low costs through chelate-based chemicals. These layers have been formulated in this study with a view to obtaining appropriate electric characteristics for an optimum photoelectric performance in the assemblies. The morphological requirements are previously fitted through a glaze that acts as a barrier layer between the deposited coating and the porcelain tile, applied through tape casting. The characterisation of the metal layers obtained is started by SEM, an AFM and the Hall effect in order to determine the morphology and chemical characteristics required for these contact layers. The electric characterisation also allows their capacity for offering an optimum performance in the assemblies to be assessed. Finally, the performance of these layers with respect to corrosion is assessed in order to complete the assessment of their industrial suitability. (Author) 13 refs.

The old open cluster Melotte 66

International Nuclear Information System (INIS)

Hawarden, T.G.

1976-01-01

Photoelectric and photographic photometry of the open cluster Melotte 66 is presented. The colour-magnitude (CM) diagram shows most of the characteristics of an old cluster. The giant branch is broad with its blue edge populated preferentially by stars from the outer parts of the cluster. There is no detectable horizontal subgiant sequence. The main sequence turn-off colour, two-colour diagram and the colour difference between the turn-off and the subgiants are used to estimate the age and composition. Melotte 66 appears to have reddening E(B-V) = 0sup(m).17 and ultraviolet excess delta(U-B) approximately 0sup(m).1. The cluster is probably between 6 and 7 x 10 9 yr old. A distance modulus (m-M) 0 =12sup(m).4 is derived, which implies that the cluster lies about 750 pc from the galactic plane. (author)

Noise and detection in ''optical'' modulation spectroscopy

International Nuclear Information System (INIS)

Montelatici, V.

1975-01-01

The measuring techniques suitable for ''optical'' modulation spectroscopy are analyzed and source of noise identified. The choice of optical detector is for photoelectrical devices. It is shown that the shot noise of phototubes is the most important noise source

MERCURY USAGE AND ALTERNATIVES IN THE ELECTRICAL AND ELECTRONICS INDUSTRIES

Science.gov (United States)

Many industries have already found alternatives for mercury or have greatly decreased mercury use. However, the unique electromechanical and photoelectric properties of mercury and mercury compounds have made replacement of mercury difficult in some applications. This study was i...

Calculation of thermal conductivity, thermal diffusivity and specific heat capacity of sedimentary rocks using petrophysical well logs

DEFF Research Database (Denmark)

Fuchs, Sven; Balling, Niels; Förster, Andrea

2015-01-01

properties (density, sonic interval transit time, hydrogen index, volume fraction of shale and photoelectric absorption index) using multivariate statistics. The application of these relations allows computing continuous borehole profiles for each rock thermal property. The uncertainties in the prediction...

14 CFR 23.239 - Spray characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Spray characteristics. 23.239 Section 23.239 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Handling Characteristics § 23.239 Spray characteristics. Spray may not dangerously obscure the vision of...

33 CFR 62.45 - Light characteristics.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Light characteristics. 62.45... characteristics. (a) Lights on aids to navigation are differentiated by color and rhythm. Lighthouses and range lights may display distinctive light characteristics to facilitate recognition. No special significance...

30 CFR 7.85 - Critical characteristics.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Critical characteristics. 7.85 Section 7.85 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND... Underground Coal Mines § 7.85 Critical characteristics. The following critical characteristics shall be...

30 CFR 7.65 - Critical characteristics.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Critical characteristics. 7.65 Section 7.65 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND... Critical characteristics. The following critical characteristics shall be inspected or tested on each...

Capstone Required System Characteristics

OpenAIRE

2004-01-01

roll roll Interactive Media Element This interactive illustration provides information about the characteristics of satellite communication systems, and the characteristics associated with each of the four categories of space segment (constellation of communication satellites). The four categories are: Narrowband (UHF) , Wideband (SHF), Protected (EHF), CommercialSimple mouseover interactions are used to reveal individual pieces of information. SS3613 Military Satellite Communi...

Preparing the COROT Space Mission: New Variable Stars in the Galactic Anticenter Direction

NARCIS (Netherlands)

Poretti, E.; Alonso, R.; Amado, P.J.; Belmonte, J.A.; Garrido, R.; Martín-Ruiz, S.; Uytterhoeven, K.; Catala, C.; Lebreton, Y.; Michel, E.; Suárez, J.C.; Aerts, C.C.; Creevey, O.; Goupil, M.J.; Mantegazza, L.; Mathias, P.; Rainer, M.; Weiss, W.W.

2005-01-01

The activities related to the preparation of the asteroseismic, photometric space mission COROT are described. Photoelectric observations, wide-field CCD photometry, uvbybeta calibrations, and further time series have been obtained at different observatories and telescopes. They have been planned to

30 CFR 7.45 - Critical characteristics

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Critical characteristics 7.45 Section 7.45 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND... characteristics The following critical characteristics shall be inspected or tested on each battery assembly to...

30 CFR 7.99 - Critical characteristics.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Critical characteristics. 7.99 Section 7.99 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND... characteristics. The following critical characteristics shall be inspected or tested on each diesel power package...

30 CFR 7.305 - Critical characteristics.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Critical characteristics. 7.305 Section 7.305 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND... characteristics. The following critical characteristics shall be inspected on each motor assembly to which an...

Tsunami sediments and their grain size characteristics

Science.gov (United States)

Sulastya Putra, Purna

2018-02-01

Characteristics of tsunami deposits are very complex as the deposition by tsunami is very complex processes. The grain size characteristics of tsunami deposits are simply generalized no matter the local condition in which the deposition took place. The general characteristics are fining upward and landward, poor sorting, and the grain size distribution is not unimodal. Here I review the grain size characteristics of tsunami deposit in various environments: swale, coastal marsh and lagoon/lake. Review results show that although there are similar characters in some environments and cases, but in detail the characteristics in each environment can be distinguished; therefore, the tsunami deposit in each environment has its own characteristic. The local geological and geomorphological condition of the environment may greatly affect the grain size characteristics.

14 CFR 23.939 - Powerplant operating characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Powerplant operating characteristics. 23... General § 23.939 Powerplant operating characteristics. (a) Turbine engine powerplant operating characteristics must be investigated in flight to determine that no adverse characteristics (such as stall, surge...

33 CFR 66.01-10 - Characteristics.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Characteristics. 66.01-10 Section 66.01-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO... Characteristics. The characteristics of a private aid to navigation must conform to those prescribed by the United...

30 CFR 7.25 - Critical characteristics.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Critical characteristics. 7.25 Section 7.25....25 Critical characteristics. A sample of each batch or lot of brattice cloth and ventilation tubing...-resistance characteristic shall be inspected or tested to ensure that the finished product will meet the...

Projection of own on others' job characteristics: evidence for the false consensus effect in job characteristics information

NARCIS (Netherlands)

Oliver, J.; Bakker, A.B.; Demerouti, E.; Jong, De R.D.

2005-01-01

The present study is an examination of the influence of rater characteristics as a source of bias in job characteristics information, as gleaned from the Job Diagnostic Survey (JDS). Participants (N=133) completed an initial JDS for own job characteristics. Non-incumbents (n = 104) then completed a

Commercial Buildings Characteristics, 1992

Energy Technology Data Exchange (ETDEWEB)

1994-04-29

Commercial Buildings Characteristics 1992 presents statistics about the number, type, and size of commercial buildings in the United States as well as their energy-related characteristics. These data are collected in the Commercial Buildings Energy Consumption Survey (CBECS), a national survey of buildings in the commercial sector. The 1992 CBECS is the fifth in a series conducted since 1979 by the Energy Information Administration. Approximately 6,600 commercial buildings were surveyed, representing the characteristics and energy consumption of 4.8 million commercial buildings and 67.9 billion square feet of commercial floorspace nationwide. Overall, the amount of commercial floorspace in the United States increased an average of 2.4 percent annually between 1989 and 1992, while the number of commercial buildings increased an average of 2.0 percent annually.

30 CFR 7.405 - Critical characteristics.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Critical characteristics. 7.405 Section 7.405... Cable Splice Kits § 7.405 Critical characteristics. (a) A sample from each production run, batch, or lot... tested, or (b) A sample of the materials that contribute to the flame-resistant characteristic of the...

Laboratory Studies of Charging Properties of Dust Grains in Astrophysical/Planetary Environments

Science.gov (United States)

Tankosic, D.; Abbas, M. M.

2012-01-01

Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with UV/X-ray radiation, as well as by electron/ion impact. Knowledge of physical and optical properties of individual dust grains is required for understanding of the physical and dynamical processes in space environments and the role of dust in formation of stellar and planetary systems. In this paper we focus on charging of individual micron/submicron dust grains by processes that include: (a) UV photoelectric emissions involving incident photon energies higher than the work function of the material and b) electron impact, where low energy electrons are scattered or stick to the dust grains, thereby charging the dust grains negatively, and at sufficiently high energies the incident electrons penetrate the grain leading to excitation and emission of electrons referred to as secondary electron emission (SEE). It is well accepted that the charging properties of individual micron/submicron size dust grains are expected to be substantially different from the bulk materials. However, no viable models for calculation of the charging properties of individual micron size dust grains are available at the present time. Therefore, the photoelectric yields, and secondary electron emission yields of micron-size dust grains have to be obtained by experimental methods. Currently, very limited experimental data are available for charging of individual micron-size dust grains. Our experimental results, obtained on individual, micron-size dust grains levitated in an electrodynamic balance facility (at NASA-MSFC), show that: (1) The measured photoelectric yields are substantially higher than the bulk values given in the literature and indicate a particle size dependence with larger particles having order-of-magnitude higher values than for submicron-size grains; (2) dust charging by low energy electron impact is a complex process. Also, our measurements indicate that

Young Children's Sibling Relationship Interactional Types: Associations with Family Characteristics, Parenting, and Child Characteristics

Science.gov (United States)

Gamble, Wendy C.; Yu, Jeong Jin

2014-01-01

Research Findings: This study examines patterns of sibling relationship qualities or interactional types and their association with family characteristics, parenting, and the characteristics of 1 of those children. Participants were 65 children (34 boys; Time 1 mean age = 51 months), their mothers, fathers, and Head Start teachers. Approximately…

Interaction of ionizing radiation with matter

International Nuclear Information System (INIS)

Calisto, Washington

1994-01-01

Definition of ionizing radiation,interaction of electrons with matter,physical model of collision,elastic and inelastic collisions,range of electron in matter,interaction of photon with matter.Photoelectric effect , Compton effect,pair production,consideration of interaction of various radiations with soft tissue

Energy characteristics of Darrieus rotor ( review)

Science.gov (United States)

Gorelov, D. N.

2010-09-01

Presented below is the review of the results of experimental studies of energy characteristics of Darrieus rotor with vertical rotation axis. Influence of main geometry parameters of the rotor on its energy characteristics has been analyzed. It is shown that Darrieus rotor may have the higher level of energy characteristics than the best propeller wind turbines.

The effect of Gd doping on the electrical and photoelectrical properties of Gd:ZnO/p-Si heterojunctions

Energy Technology Data Exchange (ETDEWEB)

Baturay, Silan [Department of Physics, Faculty of Science, Dicle University, 21280 Diyarbakir (Turkey); Ocak, Yusuf Selim, E-mail: yusufselim@gmail.com [Department of Science, Faculty of Education, Dicle University, 21280 Diyarbakir (Turkey); Science and Technology Application and Research Center, Dicle University, 21280 Diyarbakir (Turkey); Kaya, Derya [Department of Physics, Institute of Natural Applied Sciences, Dicle University, 21280 Diyarbakir (Turkey)

2015-10-05

Highlights: • Undoped and Gd doped ZnO thin films were deposited onto p-Si semiconductor. • The Gd:ZnO/p-Si heterojunctions were compared with undoped ZnO/p-Si heterojunction. • A strong effect of Gd doping on the performance of the devices were reported. - Abstract: Undoped ZnO thin films, as well as 1%, 3% and 5% Gd-doped ZnO films, were deposited on p-type Si using spin coating. The structural properties of these thin films were analysed using X-ray diffraction, and the current–voltage (I–V) and capacitance–voltage (C–V) characteristics of the Gd:ZnO/p-Si heterojunctions were compared with those of the undoped ZnO/p-Si heterojunctions. We found that Gd doping had a strong effect on the performance of the devices, and that the Gd:ZnO/p-Si heterojunctions formed with 1% Gd-doped ZnO were the most strongly rectifying, and had the highest barrier height and the lowest series resistance. Furthermore, the I–V measurements of the 1% Gd-doped ZnO/p-Si heterojunction exhibited the strongest response to light.

Modelling of hydrothermal characteristics of centrifugal nozzles

International Nuclear Information System (INIS)

Yarkho, A.A.; Omelchenko, M.P.; Borshchev, V.A.

1990-01-01

Presented for the first time is a method of recalculating the hydrothermal characteristics of centrifugal nozzles obtained in laboratory conditions for full-scale nozzles. From the experimental hydrothermal characteristics of nozzles observed in the laboratory it is allowed to calculate the hydrothermal characteristics of any other centrifugal nozzle whose diameter and dimensionless geometric characteristic are known

Stratospheric ozone conservation by electron attachment to chlorine atoms: The negative-ion chemistry

International Nuclear Information System (INIS)

Ho, D.D.M.; Tsang, K.T.; Wong, A.Y.; Siverson, R.J.

1990-01-01

Creating low-energy electrons in the stratosphere by photoelectric emission has the beneficial effect of suppressing ozone destruction by Cl. This is because Cl is converted to Cl - , which is less reactive. Critical to the success of this scheme is the ability to attach most of the electrons to Cl - and its hydrates Cl - (H 2 O). We found that this attachment efficiency is rather high. This is remarkable given the fact that the electron affinity of Cl - is less than that of NO 3 -. Photoddetachment of NO 3 - is the key factor that leads to this high efficiency. Computer calculations show that ozone increases with electron injection, and most of the electrons end up attaching to Cl - (H 2 O). We also point out that 40 km, the altitude at which most of the ozone destruction occurs, is also the optimum altitude for injecting photoelectric electrons. 12 refs., 6 figs

Barium Staminate as Semiconductor Working Electrodes for Dye-Sensitized Solar Cells

Directory of Open Access Journals (Sweden)

Fu-an Guo

2010-01-01

Full Text Available Dye-sensitized solar cells (DSSCs are fabricated with perovskite-type BaSnO3 as the photoelectrode materials. Different preparation methods including coprecipitation, hydrothermal, and solid state reaction are employed to synthesize BaSnO3 particles to optimize the photoelectric activities of electrode materials. The photoelectric properties of BaSnO3 particles and the performances of DSSCs are investigated by surface photovoltage spectroscopy and current-voltage measurements. The light-to-electricity conversion of 1.1% is preliminarily reached on the DSSC made of the coprecipitation-derived BaSnO3 particles. Large current density of hole injection into the HOMO level of N719 dye from the valence band of BaSnO3 and reduced photogenerated charge recombination in BaSnO3 could be responsible for the observed solar cell performance of the DSSC fabricated from the coprecipitation-derived BaSnO3 particles.

Rocket studies of solar corona and transition region. [X-Ray spectrometer/spectrograph telescope

Science.gov (United States)

Acton, L. W.; Bruner, E. C., Jr.; Brown, W. A.; Nobles, R. A.

1979-01-01

The XSST (X-Ray Spectrometer/Spectrograph Telescope) rocket payload launched by a Nike Boosted Black Brant was designed to provide high spectral resolution coronal soft X-ray line information on a spectrographic plate, as well as time resolved photo-electric records of pre-selected lines and spectral regions. This spectral data is obtained from a 1 x 10 arc second solar region defined by the paraboloidal telescope of the XSST. The transition region camera provided full disc images in selected spectral intervals originating in lower temperature zones than the emitting regions accessible to the XSST. A H-alpha camera system allowed referencing the measurements to the chromospheric temperatures and altitudes. Payload flight and recovery information is provided along with X-ray photoelectric and UV flight data, transition camera results and a summary of the anomalies encountered. Instrument mechanical stability and spectrometer pointing direction are also examined.

Main Characteristics of LCA

DEFF Research Database (Denmark)

Bjørn, Anders; Owsianiak, Mikołaj; Molin, Christine

2017-01-01

Life cycle assessment (LCA) has a number of defining characteristics that enables it to address questions that no other assessment tools can address. This chapter begins by demonstrating how the use of LCA in the late 2000s led to a drastic shift in the dominant perception that biofuels were “green......”, “sustainable” or “carbon neutral”, which led to a change in biofuel policies . This is followed by a grouping of the LCA characteristics into four headlines and an explanation of these: (1) takes a life cycle perspective , (2) covers a broad range of environmental issues, (3) is quantitative, (4) is based...... on science. From the insights of the LCA characteristics we then consider the strengths and limitations of LCA and end the chapter by listing 10 questions that LCA can answer and 3 that it cannot....

Database on Wind Characteristics

DEFF Research Database (Denmark)

Højstrup, J.; Ejsing Jørgensen, Hans; Lundtang Petersen, Erik

1999-01-01

his report describes the work and results of the project: Database on Wind Characteristics which was sponsered partly by the European Commision within the framework of JOULE III program under contract JOR3-CT95-0061......his report describes the work and results of the project: Database on Wind Characteristics which was sponsered partly by the European Commision within the framework of JOULE III program under contract JOR3-CT95-0061...

Cost and Demand Characteristics of Telecom Networks

DEFF Research Database (Denmark)

Falch, Morten

1997-01-01

The Chapter presents the general characteristics of the cost and demand profiles for telecommunication services and identifies the barriers towards a free competitive market for telecommunication services related to these characteristics.......The Chapter presents the general characteristics of the cost and demand profiles for telecommunication services and identifies the barriers towards a free competitive market for telecommunication services related to these characteristics....

Einstein's Revolutionary Light-Quantum Hypothesis

Science.gov (United States)

Stuewer, Roger H.

2005-05-01

The paper in which Albert Einstein proposed his light-quantum hypothesis was the only one of his great papers of 1905 that he himself termed ``revolutionary.'' Contrary to widespread belief, Einstein did not propose his light-quantum hypothesis ``to explain the photoelectric effect.'' Instead, he based his argument for light quanta on the statistical interpretation of the second law of thermodynamics, with the photoelectric effect being only one of three phenomena that he offered as possible experimental support for it. I will discuss Einstein's light-quantum hypothesis of 1905 and his introduction of the wave-particle duality in 1909 and then turn to the reception of his work on light quanta by his contemporaries. We will examine the reasons that prominent physicists advanced to reject Einstein's light-quantum hypothesis in succeeding years. Those physicists included Robert A. Millikan, even though he provided convincing experimental proof of the validity of Einstein's equation of the photoelectric effect in 1915. The turning point came after Arthur Holly Compton discovered the Compton effect in late 1922, but even then Compton's discovery was contested both on experimental and on theoretical grounds. Niels Bohr, in particular, had never accepted the reality of light quanta and now, in 1924, proposed a theory, the Bohr-Kramers-Slater theory, which assumed that energy and momentum were conserved only statistically in microscopic interactions. Only after that theory was disproved experimentally in 1925 was Einstein's revolutionary light-quantum hypothesis generally accepted by physicists---a full two decades after Einstein had proposed it.

Stratospheric aerosols

International Nuclear Information System (INIS)

Rosen, J.; Ivanov, V.A.

1993-01-01

Stratospheric aerosol measurements can provide both spatial and temporal data of sufficient resolution to be of use in climate models. Relatively recent results from a wide range of instrument techniques for measuring stratospheric aerosol parameters are described. Such techniques include impactor sampling, lidar system sensing, filter sampling, photoelectric particle counting, satellite extinction-sensing using the sun as a source, and optical depth probing, at sites mainly removed from tropospheric aerosol sources. Some of these techniques have also had correlative and intercomparison studies. The main methods for determining the vertical profiles of stratospheric aerosols are outlined: lidar extinction measurements from satellites; impactor measurements from balloons and aircraft; and photoelectric particle counter measurements from balloons, aircraft, and rockets. The conversion of the lidar backscatter to stratospheric aerosol mass loading is referred to. Absolute measurements of total solar extinction from satellite orbits can be used to extract the aerosol extinction, and several examples of vertical profiles of extinction obtained with the SAGE satellite are given. Stratospheric mass loading can be inferred from extinction using approximate linear relationships but under restrictive conditions. Impactor sampling is essentially the only method in which the physical nature of the stratospheric aerosol is observed visually. Vertical profiles of stratospheric aerosol number concentration using impactor data are presented. Typical profiles using a dual-size-range photoelectric dustsonde particle counter are given for volcanically disturbed and inactive periods. Some measurements of the global distribution of stratospheric aerosols are also presented. Volatility measurements are described, indicating that stratospheric aerosols are composed primarily of about 75% sulfuric acid and 25% water

Airfoil characteristics for wind turbines

DEFF Research Database (Denmark)

Bak, C.; Fuglsang, P.; Sørensen, Niels N.

1999-01-01

Airfoil characteristics for use in the Blade Element Momentum (BEM) method calculating the forces on Horizontal Axis Wind Turbines (HAWT) are derived by use of systematic methods. The investigation and derivation of the airfoil characteristics are basedon four different methods: 1) Inverse momentum...... theory, 2) Actuator disc theory, 3) Numerical optimisation and 4) Quasi-3D CFD computations. The two former methods are based on 3D CFD computations and wind tunnel measurements on a 41-m full-scale rotorwith LM 19.1 blades. The derived airfoil characteristics show that the lift coefficient in stall...... to a commonly used set of airfoil characteristics. The numerical optimisation is based on both the 3D CFDcomputations and measurements on a 41-m rotor with LM 19.1 and LM 19.0 blades, respectively. The method requires power and loads from a turbine and is promising since a set of lift and drag curves is derived...

Characteristics of Ethical Business Cultures

Science.gov (United States)

Ardichvili, Alexandre A.; Jondle, Douglas J.; Mitchell, James A.

2008-01-01

The purpose of this study was to identify general characteristics attributed to ethical business cultures by executives from a variety of industries. Our research identified five clusters of characteristics: (1) Mission- and Values-Driven; (2) Stakeholder Balance; (3) Leadership Effectiveness; (4) Process Integrity; and (5) Long-term Perspective.…

CONVERTER SOLAR RADIATION INTO ELECTRICITY TO SUPPLY THE AUTOMOTIVE SEMICONDUCTOR THERMOELECTRIC AIR CONDITIONING

Directory of Open Access Journals (Sweden)

T. A. Ismailov

2015-01-01

Full Text Available The article considers the possibility to increase the efficiency of converters of solar radiation into electricity by combining constructive photoelectric effect, See-beck thermoeffect and semiconductor solar cells, which will create integrated device to provide power semiconductor thermoelectric automobile air conditioner. 

Project Physics Handbook 5, Models of the Atom.

Science.gov (United States)

Harvard Univ., Cambridge, MA. Harvard Project Physics.

Five experiments and 19 activities are presented in this Unit 5 handbook. The experiments are related to electrolysis, charge-to-mass ratio, elementary charge determination, photoelectric effects, and spectroscopic analyses. The activities are concerned with Dalton's theory, water electrolysis, periodic tables, single-electron plating, cloud…

Spectroscopic Binaries near the North Galactic Pole Paper 24: HD ...

Indian Academy of Sciences (India)

R. Narasimhan (Krishtel eMaging Solutions)

Paper 24: HD 106104, 109281, 109463 and 110743. R. F. Griffin, The ... with photoelectric radial-velocity spectrometers for many years. They have ..... G3 V against the principal star's F9 V, so the two objects would very well pass for a physical ...

Sky luminance research imperative for adequate ciontrol of temporary supplementary artificial lighting installations

NARCIS (Netherlands)

Rutten, A.J.F.

1994-01-01

The energy consumption in Dutch office buildings can be cut considerably if daylight is used as task lighting. A conservative estimate gives a potential saving of 46% on the electricity costs for artificial lighting. The problem of photo-electric control of artificial lighting supplementing the

Learner characteristics involved in distance learning

Energy Technology Data Exchange (ETDEWEB)

Cernicek, A.T.; Hahn, H.A.

1991-01-01

Distance learning represents a strategy for leveraging resources to solve educational and training needs. Although many distance learning programs have been developed, lessons learned regarding differences between distance learning and traditional education with respect to learner characteristics have not been well documented. Therefore, we conducted a survey of 20 distance learning professionals. The questionnaire was distributed to experts attending the second Distance Learning Conference sponsored by Los Alamos National Laboratory. This survey not only acquired demographic information from each of the respondents but also identified important distance learning student characteristics. Significant distance learner characteristics, which were revealed statistically and which influence the effectiveness of distance learning, include the following: reading level, student autonomy, and self-motivation. Distance learning cannot become a more useful and effective method of instruction without identifying and recognizing learner characteristics. It will be important to consider these characteristics when designing all distance learning courses. This paper will report specific survey findings and their implications for developing distance learning courses. 9 refs., 6 tabs.

Photoelectric properties by interface effect of organic/inorganic(CuPc/PbTe) multilayer prepared by pulsed laser deposition and thermal evaporation

CERN Document Server

Lee, H Y; Choi, B C; Jeong, J H; Tabata, H; Kawai, T

1999-01-01

Highly crystallized CuPc/PbTe multilayer are prepared at substrate temperature from room temperature to 300 .deg. C by pulsed laser deposition and thermal evaporation method. From the measurement of AFM image, these all film exhibits composed of round grains and flat matrix. For observation the interface effect of multilayer, we measured the transverse current-voltage characteristics in the dark and under illumination. The photocarrier is generated in the CuPc layer and the electron-hole pairs are separated by the steep incline of the potential near the CuPc/PbTe interface. The CuPc/PbTe multilayers in the in-plane current-voltage curve exhibit larger photoconduction effect than that of CuPc single layer.

Resident Characteristics Report

Data.gov (United States)

Department of Housing and Urban Development — The Resident Characteristics Report summarizes general information about households who reside in Public Housing, or who receive Section 8 assistance. The report...

Choice of excitation source for determination of rare earth elements with radioisotope excited X ray fluorescence

International Nuclear Information System (INIS)

Zhang Quanshi; Chang Yongfu

2000-01-01

The comparisons of two radioisotope source ( 241 Am and 238 Pu) which are the most available in the radioisotope excited X Ray Fluorescence (XRF) analysis technique and two characteristic X ray series (KX and LX) analyzed for the determination of the rare-earth (RE) elements were investigated in detail. According to the principle of emission and detection of X ray , the relative excitation efficiencies were calculated by the some fundamental physical parameters including the photoelectric mass attenuation coefficient, the fluorescent yield, the absorption jump factor, the emission probability of the detected fluorescent line with reference to other liens of the same series etc., The advantages and disadvantages of the two conditions are discussed. These results may determine the optimal excitation and detection conditions for different rare-earth elements. The experimental results with nine rare-earth elements (Ce, Nd, Sm, Tb, Tm, Ho, Er, Yb and Lu) are in agreement with the results of theoretical calculations

Research on distributed optical fiber sensing data processing method based on LabVIEW

Science.gov (United States)

Li, Zhonghu; Yang, Meifang; Wang, Luling; Wang, Jinming; Yan, Junhong; Zuo, Jing

2018-01-01

The pipeline leak detection and leak location problem have gotten extensive attention in the industry. In this paper, the distributed optical fiber sensing system is designed based on the heat supply pipeline. The data processing method of distributed optical fiber sensing based on LabVIEW is studied emphatically. The hardware system includes laser, sensing optical fiber, wavelength division multiplexer, photoelectric detector, data acquisition card and computer etc. The software system is developed using LabVIEW. The software system adopts wavelet denoising method to deal with the temperature information, which improved the SNR. By extracting the characteristic value of the fiber temperature information, the system can realize the functions of temperature measurement, leak location and measurement signal storage and inquiry etc. Compared with traditional negative pressure wave method or acoustic signal method, the distributed optical fiber temperature measuring system can measure several temperatures in one measurement and locate the leak point accurately. It has a broad application prospect.

Variation of sulfur content in Cu(In,Ga)(S,Se){sub 2} thin film solar cells

Energy Technology Data Exchange (ETDEWEB)

Knipper, Martin; Knecht, Robin; Riedel, Ingo; Parisi, Juergen [Energy and Semiconductor Research Laboratory, Department of Physics, University of Oldenburg (Germany)

2011-07-01

Chalcopyrite thin film solar cells made of the compound semiconductor Cu(In,Ga)(S,Se){sub 2} (CIGSSe) have a strong potential for achieving high efficiencies at low production costs. Volume production of CIGSSe-modules has already started to exploit their favorable attributes such as low cost processing and reasonable module efficiency. In this study we studied industrially produced CIGSSe modules obtained from rapid thermal processing (RTP) for sulfurization. In detail, we investigated the effect of sulfur offer and RTP temperature (500 C to 580 C) on the photoelectric characteristics of small-area solar cells cut from the modules. Current-voltage profiling under standard test conditions revealed a strong influence of the particular process recipe on the open circuit voltage whereas significant variations of the maximum quantum efficiency can be observed. X-ray diffraction was employed to relate these effects to the crystallographic structure of the actual CIGSSe films. Lock-in thermographic imaging was employed to link apparent film inhomogeneities and disruptions to the specific process recipe.

Imaging quality evaluation method of pixel coupled electro-optical imaging system

Science.gov (United States)

He, Xu; Yuan, Li; Jin, Chunqi; Zhang, Xiaohui

2017-09-01

With advancements in high-resolution imaging optical fiber bundle fabrication technology, traditional photoelectric imaging system have become ;flexible; with greatly reduced volume and weight. However, traditional image quality evaluation models are limited by the coupling discrete sampling effect of fiber-optic image bundles and charge-coupled device (CCD) pixels. This limitation substantially complicates the design, optimization, assembly, and evaluation image quality of the coupled discrete sampling imaging system. Based on the transfer process of grayscale cosine distribution optical signal in the fiber-optic image bundle and CCD, a mathematical model of coupled modulation transfer function (coupled-MTF) is established. This model can be used as a basis for following studies on the convergence and periodically oscillating characteristics of the function. We also propose the concept of the average coupled-MTF, which is consistent with the definition of traditional MTF. Based on this concept, the relationships among core distance, core layer radius, and average coupled-MTF are investigated.

Mobile solar mini power station filled with infrared heliochambers

International Nuclear Information System (INIS)

Abdukadirov, M.A.; Akhmedova, N.A.

2000-01-01

The work dedicated to development of perspective types of solar energetic devices of in-land application in accordance with conception about advantage of decentralized production of electrical and heat energy for supply of atom customers. It is given constructive particulars and characteristics of developed by authors mobile energy complex, which contents from block photoelectrical of convertor on the base of semiconductor solar elements, transparent in longwaved area out of edge of absorption base band, with power from 100 till 1000 Wt and heliochamber for accumulation of infrared part of solar radiation with wave length λ> 1 mcm. It is shown that, introduction into the system of energy complex the infrared heliochamber, increase the efficiency of equipment generally on the account of increasing the useful application of solar spectrum and extend her functional abilities. It is discussed the advantages of similar energy complex at decision of separate production tasks, including agriculture processing. (Author)

A study on the fusion reactor - Development of x-ray spectrometer for diagnosis of tokamak plasma

Energy Technology Data Exchange (ETDEWEB)

Jang, Hong Young; Choi, Duk In; Seo, Sung Hun; Kwon, Gi Chung; Jun, Sang Jin; Heo, Sung Hoi; Lee, Chan Hui [Korea Advanced Institute of Science and Technolgoy, Taejon (Korea, Republic of)

1996-09-01

This report of research is on the development of X-ray Photo-Electron Spectrometer (PES) for diagnosis of tokamak plasma. The spectrometer utilizes the fact that the energy of photo-electron is given by the difference between the energy of X-ray and the binding energy of materials. In the research of this year, we constructed two spectrometers; one is operated in KAIST tokamak and the other in KT1 tokamak. In addition, we reviewed the characteristics of the x-ray filter, the photo-electric effect of carbon foils and the detection efficiency of MCP and x-ray radiation of plasma. We measured the x-ray radiation in tokamak and diagnosed the qualitative plasma parameters from the analysis of data. The major interesting plasma parameters, which we can diagnose with the spectrometer, are the electron temperature, Z{sub eff}, the spatial distribution of x-ray radiation and etc. 27 refs., 2 tabs., 20 figs. (author)

Lighting and energy performance for an office using high frequency dimming controls

International Nuclear Information System (INIS)

Li, Danny H.W.; Lam, Tony N.T.; Wong, S.L.

2006-01-01

Artificial lighting is one of the major electricity consuming items in many non-domestic buildings. Recently, there has been an increasing interest in incorporating daylight in architectural and building designs to reduce the electricity use and enhance greener building developments. This paper presents field measurements for a fully air conditioned open plan office using a photoelectric dimming system. Electric lighting load, indoor illuminance levels and daylight availability were systematically measured and analyzed. The general features and characteristics of the results such as electric lighting energy savings and transmitted daylight illuminance in the forms of frequency distributions and cumulative frequency distributions are presented. Daylighting theories and regression models have been developed and discussed. It has been found that energy savings in electric lighting were over 30% using the high frequency dimming controls. The results from the study would be useful and applicable to other office spaces with similar architectural layouts and daylight linked lighting control systems

7 CFR 51.632 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.632 Section 51.632 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards..., and Arizona) Definitions § 51.632 Similar varietal characteristics. Similar varietal characteristics...

48 CFR 47.305-16 - Shipping characteristics.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Shipping characteristics... CONTRACT MANAGEMENT TRANSPORTATION Transportation in Supply Contracts 47.305-16 Shipping characteristics... shipments of agreed size. (b) Guaranteed shipping characteristics. (1) The contracting officer shall insert...

7 CFR 51.694 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.694 Section 51.694 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards..., and Arizona) Definitions § 51.694 Similar varietal characteristics. Similar varietal characteristics...

Photoelectric Radial Velocities, Paper XX 45 Years' Monitoring of ...

Indian Academy of Sciences (India)

... through the 'Open Horizons' schol- arship programme. She is also grateful to the Institute of Astronomy, Cambridge, for a summer studentship kindly funded personally by Prof. D. Lynden-Bell, to whom also R.F.G. is much indebted for the provision in that way of technical computing skills well beyond his own. References.

Photoelectrical behavior of perylene derivative.pi.-conjugated polymer system

Czech Academy of Sciences Publication Activity Database

Podhájecká, Klára; Matějíček, P.; Vohlídal, J.; Masuda, T.; Pfleger, Jiří

2008-01-01

Roč. 158, 19-20 (2008), s. 775-781 ISSN 0379-6779 R&D Projects: GA ČR GP203/06/P226; GA AV ČR IAA4050406 Institutional research plan: CEZ:AV0Z40500505 Keywords : poly(diphenylacetylene) * organic photovoltaic s * heterojunction Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.962, year: 2008

Photoelectrical properties of semiconductor tips in scanning tunneling microscopy

NARCIS (Netherlands)

Prins, M.W.J.; Jansen, R.; Groeneveld, R.H.M.; Gelder, Van A.P.; Kempen, van H.

1996-01-01

We describe a model as well as experiments on the electrical properties of a photoexcited tunnel junction between a metal and a semiconductor material, as is established in a scanning tunneling microscope. The model treats the case in which carrier transport is mediated by capture and relaxation in

Characteristics of the quarry as shielding for {sup 241}AmBe neutrons and monoenergetic photons; Caracteristicas de la cantera como blindaje para los neutrones del {sup 241}AmBe y fotones monoenergeticos

Energy Technology Data Exchange (ETDEWEB)

Vega C, H. R.; Hernandez D, V. M.; Letechipia de L, C.; Salas L, M. A. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico); Rodriguez R, J. A.; Juarez A, C. A., E-mail: fermineutron@yahoo.com [Universidad Autonoma de Nuevo Leon, Facultad de Ingenieria Civil, Pedro de Alba s/n, San Nicolas de los Garza, Nuevo Leon (Mexico)

2016-09-15

Shielding is an important element in radiation protection since allows the management of radiation sources. Currently there are different materials of natural or anthropogenic origin that are used as shielding for both photons and neutrons. The quarry is a material of natural origin and abundant in our country, which is used in construction or for the manufacture of sculptures, however its characteristics as shielding have not been reported. In this paper we report some of the properties of the quarry as shielding for monoenergetic photons and for neutrons produced by an isotopic neutron source of {sup 241}AmBe. A quarry piece was used to determine its density and its chemical composition, with the XCOM code the elemental composition was determined and the mass interaction and total attenuation coefficients of the quarry were determined with photons of 10{sup -3} to 10{sup -5} MeV; the interaction coefficients included coherent dispersion, photoelectric absorption, Compton dispersion and the production of pairs in the nuclear and electronic field. Using the MCNP5 code, a narrow geometry attenuation experiment was modeled and the photon fluence was estimated that reaches a point detector at a distance of 42 cm from a point source, isotropic and monoenergetic photon when the source and the point detector were added quarry pieces of different thicknesses. The reduction of the number of photons as a function of the thickness of the quarry was used to determine the coefficient of linear attenuation of the quarry before photons of 0.03, 0.07, 0.1, 0.3, 1, 2 and 3 MeV that were the same as those calculated with the XCOM code. With the MCNP, the K a and H(10) transmission curves were also calculated. This same model was used to determined the variation of the {sup 241}AmBe neutron spectrum as a function of quarry thickness, as well as the E{sub ROT} and H(10) transmission curves. (Author)

7 CFR 51.1154 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.1154 Section 51.1154 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... varietal characteristics. Similar varietal characteristics means that the fruits in any container are...

7 CFR 51.3202 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.3202 Section 51.3202 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Similar varietal characteristics. Similar varietal characteristics means that the onions in any container...

MAX Provider Characteristics

Data.gov (United States)

U.S. Department of Health & Human Services — The MAX Provider Characteristics (PC) File Implementation Report describes the design, implementation, and results of the MAXPC prototype, which was based on three...

7 CFR 51.1550 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.1550 Section 51.1550 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... characteristics. Similar varietal characteristics means that the potatoes in any lot have the same general shape...

7 CFR 51.2756 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.2756 Section 51.2756 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... characteristics. Similar varietal characteristics means that the peanut kernels in the lot are not of distinctly...

7 CFR 51.763 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.763 Section 51.763 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... characteristics. Similar varietal characteristics means that the fruits in any container are similar in color and...

7 CFR 51.3057 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.3057 Section 51.3057 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... characteristics. Similar varietal characteristics means that the avocados in any container are similar in shape...

7 CFR 51.2714 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.2714 Section 51.2714 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... characteristics. Similar varietal characteristics means that the peanut kernels in the lot are not of distinctly...

7 CFR 51.603 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.603 Section 51.603 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... characteristics. Similar varietal characteristics means that the stalks in any container have the same character...

7 CFR 51.2650 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.2650 Section 51.2650 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... characteristics. Similar varietal characteristics means that the cherries in any container are similar in color...

Characteristics of reversible-pump turbines

Energy Technology Data Exchange (ETDEWEB)

Olimstad, Grunde

2012-07-01

The primary goal for this PhD project has been to investigate instability of reversible-pump turbines (RPTs) as a phenomenon and to find remedies to solve it. The instability occurs for turbines with s-shaped characteristics, unfavourable waterway and limited rotating inertia. It is only observed for certain operation pints at either high speed or low load. These correspond to ether high values of Ned or low values of Qed. The work done in this PhD thesis can be divided in to the three following categories. Investigate and understand the behaviour of a pump turbine: A model was designed in order to investigate the pump turbine behaviour related to its characteristics. This model was manufactured and measurements were performed in the laboratory. By using throttling valves or torque as input the full s-shaped characteristics was measured. When neither of these techniques is used, the laboratory system has unstable operation points which result in hysteresis behaviour. Global behaviour of the RPT in power plant system was investigated through analytical stability analysis and dynamic system simulations. The latter included both rigid and elastic representation of the water column. Turbine internal flow: The flow inside the runner was investigated by computer simulations (CFD). Two-dimensional analysis was used to study the inlet part of the runner. This showed that a vortex forming at the inlet is one of the causes for the unstable operation range. Measurements at different pressure levels showed that the characteristics were dependent on the Reynolds number at high Ned values in turbine mode. This means that the similarity of flows is not sufficiently described by constant Qed and Ned values at this part of the characteristics. Design modifications: The root of the stability problem was considered to be the runners geometric design at the inlet in turbine mode. Therefore different design parameters were investigated to find relations to the characteristics. Methods

Albert Einstein and 20th century's physics

International Nuclear Information System (INIS)

Zajac, R.

1979-01-01

Albert Einstein's teaching and his three fundamental works are discussed dealing with the molecular theory of heat applied to the motion of suspended particles in liquids at rest, the photoelectric effect, and the theory of relativity. Albert Einstein's impact on contemporary physics is evaluated. (J.P.)

B and V photometry and analysis of the eclipsing binary RZ CAS

Science.gov (United States)

Riazi, N.; Bagheri, M. R.; Faghihi, F.

1994-01-01

Photoelectric light curves of the eclipsing binary RZ Cas are presented for B and V filters. The light curves are analyzed for light and geometrical elements, starting with a previously suggested preliminary method. The approximate results thus obtained are then optimised through the Wilson-Devinney computer programs.

Hot Electron Photoemission from Plasmonic Nanoparticles: Role of Transient Absorption in Surface Mechanism

DEFF Research Database (Denmark)

Uskov, Alexander V.; Protsenko, Igor E.; Ikhsanov, Renat S.

2014-01-01

We analyze and compare surface- and vol ume-based internal photoelectric effects from spherical nanoparticles, obtaining analytical expression s for the photoemission rate in both cases. Similar to results for a flat metal surface, one can show that the surface mechanism preva ils, since it is un...

Computational studies on energetic properties of nitrogen-rich ...

Indian Academy of Sciences (India)

Computational studies on energetic properties of nitrogen-rich energetic materials with ditetrazoles. LI XIAO-HONGa,b,∗ and ZHANG RUI-ZHOUa. aCollege of Physics and Engineering, Henan University of Science and Technology, Luoyang 471 003, China. bLuoyang Key Laboratory of Photoelectric Functional Materials, ...

Reduction of the photoelectron induced gas desorption in the PETRA vacuum system by in situ argon flow discharge cleaning

International Nuclear Information System (INIS)

Kouptsidis, J.; Mathewson, A.G.

1976-09-01

In this paper the authors calculate the photon energy distribution of the synchrotron radiation for the 5-19 GeV energy range of PETRA and from published values of the experimentally measured photoelectric yield of Al they calculate the total number of photoelectrons produced. (orig./HW) [de

Compilations and evaluations of data on the interaction of electromagnetic radiation with matter

International Nuclear Information System (INIS)

Lorenz, A.

1978-05-01

The material contained in this report deals with data on the interaction of electromagnetic radiation with matter, listing major compilations of X-ray, photon and gamma-ray cross sections and attentuation coefficients, as well as selected reports featuring data on compton scattering, photoelectric absorption and pair production

14 CFR 29.939 - Turbine engine operating characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be investigated in flight to determine that no adverse characteristics (such as stall, surge, of flameout) are...

14 CFR 25.939 - Turbine engine operating characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbine engine operating characteristics... engine operating characteristics. (a) Turbine engine operating characteristics must be investigated in flight to determine that no adverse characteristics (such as stall, surge, or flameout) are present, to a...

14 CFR 27.939 - Turbine engine operating characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be investigated in flight to determine that no adverse characteristics (such as stall, surge, or flameout) are...

SYSTEM ANALYSIS OF INTERRELATIONS BETWEEN SPECTRAL CHARACTERISTICS OF THE STEEL MICROSTRUCTURE PICTURE AND ITS MECHANICAL CHARACTERISTICS IN METALLURGICAL PRODUCTION

Directory of Open Access Journals (Sweden)

A. N. Chichko

2009-01-01

Full Text Available It is shown that spectral characteristics of functions of closeness of the pearlite inter-plate distances, determined by image of the rolled wire samples microstructures, correlate with its mechanical characteristics and also with characteristics of wire, produced of it.

24 CFR 241.890 - Characteristics of debentures.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Characteristics of debentures. 241... Insurance § 241.890 Characteristics of debentures. Debentures issued in settlement of insurance claims under this subpart shall have the same characteristics and the same requirements for registration and...

7 CFR 51.1906 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.1906 Section 51.1906 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... characteristics. Similar varietal characteristics means that the tomatoes are alike as to color, i.e., bright red...

7 CFR 51.567 - Similar varietal characteristics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Similar varietal characteristics. 51.567 Section 51... STANDARDS) United States Standards for Celery Definitions § 51.567 Similar varietal characteristics. Similar varietal characteristics means that the stalks in any package have the same general appearance and...

Saint Venant's equation and theory of characteristics

International Nuclear Information System (INIS)

Daubert, Andre

1978-01-01

This theory, in its general scope, will be dealt with through the concrete example of Saint Venant's equations which govern the waves in channels. 1. Finding the characteristic directions. The aim is to interpret the hyperbolic sort of equations to show that there is a way of combining them in order to shape them so that they express a linear relation between the variations of the unknowns when moving along particular differential paths. In certain cases, this differential relation can integrate to lead to Rieman's invariants. 2. Relation between the theory of characteristics and the wave equation. In the linear systems case, it is worthwhile showing simply, how the method of characteristics is linked to the conventional treatment of the wave equation. 3. Relation between the theory of characteristics and the Cauchy problem. The theory of characteristics is frequently introduced as from the Cauchy problem, the characteristics forming the conditions of indetermination of the Cauchy problem [fr

Gravitational wave extraction based on Cauchy-characteristic extraction and characteristic evolution

Energy Technology Data Exchange (ETDEWEB)

Babiuc, Maria [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Szilagyi, Bela [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Golm (Germany); Hawke, Ian [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Golm (Germany); School of Mathematics, University of Southampton, Southampton SO17 1BJ (United Kingdom); Zlochower, Yosef [Department of Physics and Astronomy, and Center for Gravitational Wave Astronomy, University of Texas at Brownsville, Brownsville, TX 78520 (United States)

2005-12-07

We implement a code to find the gravitational news at future null infinity by using data from a Cauchy code as boundary data for a characteristic code. This technique of Cauchy-characteristic extraction (CCE) allows for the unambiguous extraction of gravitational waves from numerical simulations. We first test the technique on non-radiative spacetimes: Minkowski spacetime, perturbations of Minkowski spacetime and static black hole spacetimes in various gauges. We show the convergence and limitations of the algorithm and illustrate its success in cases where other wave extraction methods fail. We further apply our techniques to a standard radiative test case for wave extraction, a linearized Teukolsky wave, presenting our results in comparison to the Zerilli technique, and we argue for the advantages of our method of extraction.

Photosensitizers from Spirulina for Solar Cell

Directory of Open Access Journals (Sweden)

Liqiu Wang

2014-01-01

Full Text Available Spirulina is a kind of blue-green algae with good photosynthetic efficiency and might be used for photovoltaic power generation. So this paper used living spirulina as novel photosensitizer to construct spirulina biosolar cell. The results showed that spirulina had the photoelectric conversion effect, and could let the spirulina biosolar cell have 70 μA photocurrent. Meanwhile, adding glucose sucrose or chitosan in the spirulina anode chamber, they could make the maxima current density of the cell greatly increased by 80 μA, 100 μA, and 84 μA, respectively, and the sucrose could improve the maximum power density of the cell to 63 mW/m−2. Phycobiliprotein played an important role in the photosynthesis of spirulina. So in this paper phycobiliprotein was extracted from spirulina to composite with squaraine dye to sensitize nanocrystalline TiO2 photoanode for building dye sensitized solar cell, and the photoelectric properties of the cell also were investigated.

Measurement of the x-ray mass attenuation coefficient and determination of the imaginary component of the atomic form factor of molybdenum over the 13.5-41.5-keV energy range

International Nuclear Information System (INIS)

Jonge, Martin D. de; Tran, Chanh Q.; Chantler, Christopher T.; Barnea, Zwi; Dhal, Bipin B.; Cookson, David J.; Lee, Wah-Keat; Mashayekhi, Ali

2005-01-01

We use the x-ray extended-range technique (XERT) [Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of molybdenum in the x-ray energy range of 13.5-41.5 keV to 0.02-0.15 % accuracy. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct where necessary a number of experimental systematic errors. These results represent the most extensive experimental data set for molybdenum and include absolute mass attenuation coefficients in the regions of the x-ray absorption fine structure (XAFS) and x-ray-absorption near-edge structure (XANES). The imaginary component of the atomic form-factor f 2 is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-15 % persist between the calculated and observed values

Development of a New X-Ray Polarization Detection Device

Science.gov (United States)

Thompson, Jahreem R.; Hill, Joanne E.; Jahoda, Keith; Black, Kevin; Querrard, Rodney

2018-01-01

The aim of this research is to confirm the functionality of a Gas Electron Multiplier made of stainless steel in a detection medium of carbon dioxide and nitromethane through a series of X-ray tests in a vacuum chamber. Utilizing the photoelectric effect with carbon dioxide and nitromethane, we can confirm polarization of X-rays emitted from the most extreme astronomical conditions. We chose to use CO2 because we can confirm that it works well with the stainless-steel detector based on previous tests and nitromethane because we suspect that the ionization electrons created by the photoelectron during the photoelectric effect will experience less diffusion if they are bonded to a large molecule such as nitromethane as they diffuse towards the drift plate. The development of these new X-ray polarimeters will help to further the study of gravitational fields near black holes, their effects on matter they encounter, and the magnetic fields of neutron stars.

US Photovoltaic Patents, 1988--1990

Energy Technology Data Exchange (ETDEWEB)

1991-12-01

This document contains US patents on terrestrial photovoltaic (PV) power applications, including systems, components, and materials, as well as manufacturing and support functions. The patent entries in this document were issued from 1988 through 1990. The entries were located by searching USPA, the data base of the US Patent Office. The final search retrieved all patents under the class ``Batteries, Thermoelectric and Photoelectric`` and the subclasses ``Photoelectric,`` ``Testing,`` and ``Applications.`` The search also located patents that contained the words ``photovoltaic(s)`` or ``solar cell(s)`` and their derivatives. A manual search of the patents in the Solar Energy Research Institute (SERI) patent file augmented the data base search. After the initial list was compiled, most of the patents on the following subjects were excluded: space photovoltaic technology, use of the photovoltaic effect for detectors and subjects only peripherally concerned with photovoltaics. Some patents on these three subjects were included when it appeared that those inventions might be of use in terrestrial PV power technologies.

Inhibition of quantum size effects from surface dangling bonds: The first principles study on different morphology SiC nanowires

Science.gov (United States)

Li, Yan-Jing; Li, Shu-Long; Gong, Pei; Li, Ya-Lin; Fang, Xiao-Yong; Jia, Ya-Hui; Cao, Mao-Sheng

2018-06-01

In recent years, we investigated the structure and photoelectric properties of Silicon carbide nanowires (SiCNWs) with different morphologies and sizes by using the first-principle in density functional theory, and found a phenomenon that is opposite to quantum size effect, namely, the band gap of nanowires increases with the increase of the diameter. To reveal the nature of this phenomenon, we further carry out the passivation of SiCNWs. The results show that the hydrogenated SiCNWs are direct band gap semiconductors, and the band gap decreases with the diameter increasing, which indicates the dangling bonds of the SiCNWs suppress its quantum size effect. The optical properties of SiCNWs with different diameters before and after hydrogenated are compared, we found that these surface dangling bonds lead to spectral shift which is different with quantum size effect of SiCNWs. These results have potential scientific value to deepen the understanding of the photoelectric properties of SiCNWs and to promote the development of optoelectronic devices.

Device for controlling the composition of the mixture burnt in the combustion spaces of an internal combustion engine. Einrichtung zur Regelung der Zusammensetzung des in den Brennraeumen einer Brennkraftmaschine zur Verbrennung kommenden Betriebsgemisches

Energy Technology Data Exchange (ETDEWEB)

Latsch, R; Bianchi, V

1986-07-31

The purpose of the invention is to create a device by which the extent of the reaction to the control of the composition of the mixture burnt in the combustion spaces of an internal combustion engine can be measured in a sensitive, responsive and safe way, where the position of the elements detecting the reaction should have a relatively small effect on the accuracy of the measurement and the extent of measurement. According to the invention, this problem is solved by the use of 2 thermal sensors connected to a control device (photo-electric diode, photo-electric transistor), one of which acts catalytically and causes the parts of the gas mixture there to react. The thermal sensor output signals are periodically integrated via the piston work and are entered in the control device. The measured temperature is a measure of how far the method of operation of the internal combustion engine has approached its limits. (HWJ).

[Collage work characteristics and personality].

Science.gov (United States)

Sato, Shizuka

2002-06-01

The purpose of this study was to investigate the relationship between personality and characteristics in collage work. Seventy undergraduates filled the Yatabe-Guilford (YG) personality test and produced a piece of collage work. The YG personality types were not different in terms of collage work characteristics. However, emotional adaptation and introvert/extrovert scores were reflected in the number of cuttings used in the piece. General activity score was reflected in the number of vehicle pictures used. Those who used an eye picture had a tendency to be depressed and lacking in confidence. Those who used a "stone circle" picture tended to be more emotionally adapted and extroverted. The results suggested a possibility that personality traits were reflected in specific characteristics in collage work.

14 CFR 35.7 - Features and characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Features and characteristics. 35.7 Section... AIRWORTHINESS STANDARDS: PROPELLERS General § 35.7 Features and characteristics. (a) The propeller may not have features or characteristics, revealed by any test or analysis or known to the applicant, that make it...

14 CFR 23.253 - High speed characteristics.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false High speed characteristics. 23.253 Section... Requirements § 23.253 High speed characteristics. If a maximum operating speed VMO/MMO is established under § 23.1505(c), the following speed increase and recovery characteristics must be met: (a) Operating...

Modeling of static characteristics of switched reluctance motor

International Nuclear Information System (INIS)

Asgharmemon, A.; Hussain, I.; Daudpoto, J.

2013-01-01

To investigate the running characteristics of a switched reluctance motor, the static characteristics and related input data tables are required. The static characteristics comprise of flux linkage, co-energy and static torque characteristics. The co-energy and static torque are calculated once data of magnetization characteristics is available. The data of co-energy is required for the calculation of static torque characteristics. The simulation model includes the data of static characteristics for prediction of the instantaneous and steady state performance of the motor. In this research a computer based procedure of experiments is carried out for measurement of the magnetization characteristics. For every set of measurements, the removal of eddy current is carefully addressed. The experiments are carried out on an existing 8/6 pole rotary switched reluctance motor. Additionally, the instantaneous phase current, instantaneous torque and flux waveforms are produced by using linear, which is by default and spline data interpolation separately. The information obtained from theses simulation results will help in an improved simulation model for predicting the performance of the machine. (author)

Cyclic characteristics of earthquake time histories

International Nuclear Information System (INIS)

Hall, J.R. Jr; Shukla, D.K.; Kissenpfennig, J.F.

1977-01-01

From an engineering standpoint, an earthquake record may be characterized by a number of parameters, one of which is its 'cyclic characteristics'. The cyclic characteristics are most significant in fatigue analysis of structures and liquefaction analysis of soils where, in addition to the peak motion, cyclic buildup is significant. Whereas duration peak amplitude and response spectra for earthquakes have been studied extensively, the cyclic characteristics of earthquake records have not received an equivalent attention. Present procedures to define the cyclic characteristics are generally based upon counting the number of peaks at various amplitude ranges on a record. This paper presents a computer approach which describes a time history by an amplitude envelope and a phase curve. Using Fast Fourier Transform Techniques, an earthquake time history is represented as a projection along the x-axis of a rotating vector-the length the vector is given by the amplitude spectra-and the angle between the vector and x-axis is given by the phase curve. Thus one cycle is completed when the vector makes a full rotation. Based upon Miner's cumulative damage concept, the computer code automatically combines the cycles of various amplitudes to obtain the equivalent number of cycles of a given amplitude. To illustrate the overall results, the cyclic characteristics of several real and synthetic earthquake time histories have been studied and are presented in the paper, with the conclusion that this procedure provides a physical interpretation of the cyclic characteristics of earthquakes. (Auth.)

Characteristic manifolds in relativistic hypoelasticity

Energy Technology Data Exchange (ETDEWEB)

Giambo, S [Messina Univ. (Italy). Istituto di Matematica

1978-10-02

The relativistic hypoelasticity is considered and the characteristic manifolds are determined by using the Cauchy-Kovalevski theorem for the Cauchy problem with analytic initial conditions. Taking into account that the characteristic manifold represents the image of the front-wave in the space-time, it is possible to determine the velocities of propagation. Three wave-species are obtained: material waves, longitudinal waves and transverse waves.

Wastewater Characteristics, Treatment and Disposal

OpenAIRE

Von Sperling, Marcos

2007-01-01

"Wastewater Characteristics, Treatment and Disposal is the first volume in the series Biological Wastewater Treatment, presenting an integrated view of water quality and wastewater treatment. The book covers the following topics: wastewater characteristics (flow and major constituents) impact of wastewater discharges to rivers and lakes overview of wastewater treatment systems complementary items in planning studies. This book, with its clear and practical approach, lays the foundations f...

40 CFR 796.1050 - Absorption in aqueous solution: Ultraviolet/visible spectra.

Science.gov (United States)

2010-07-01

... applied to measure the absorption spectra. (b) Method—(1)(i) Introduction, purpose, scope, relevance... volume of HCl or NaOH in aqueous solution ([HCl], [NaOH]=1 mol/L). (4) In theory, all chemical species...) Katelaar, J.A.A., Photoelectric Spectrometry Group Bulletin, 8, (Cambridge, 1955). (3) Chemical Rubber...

Ten colour photometry of twelve Ap-stars

International Nuclear Information System (INIS)

Musielok, B.; Lange, D.; Schoeneich, W.; Hildebrandt, G.; Zelwanowa, E.; Hempelmann, A.; Salmanov, G.

1980-01-01

Ten-colour photoelectric observations are presented for twelve Ap-stars. Improved ephemeris for seven of them is given. Phase relations between the light curves and line intensity variations are discussed. The problem of the electromagnetic flux conctancy of IOTA Cas is approached from a qualitative point of view. (author)

Fulltext PDF

Indian Academy of Sciences (India)

user1

Self-Similar Solutions for Viscous and Resistive Advection Dominated Accretion. Flows (Kazem Faghei), 9. Photoionization Cross-Section of Chlorine-like Iron ... Photoelectric Radial Velocities, Paper XX: 45 Years' Monitoring of the Radial. Velocities of the Redman K Stars (R. F. Griffin & A. Stroe), 245. On the Maximum ...

The Discovery of HD 37605c and a Dispositive Null Detection of Transits of HD 37605b

DEFF Research Database (Denmark)

Xuesong Wang, Sharon; Wright, Jason T.; Cochran, William

2012-01-01

the predicted ephemeris, we performed a transit search for HD 37605b with the photometric data taken by the T12 0.8-m Automatic Photoelectric Telescope (APT) and the Microvariability and Oscillations of Stars (MOST) satellite. Though the APT photometry did not capture the transit window, it characterized...

Measurements of integral cross-sections of incoherent interactions of photons with L-shell electrons

Energy Technology Data Exchange (ETDEWEB)

Verma, S L; Allawadhi, K L; Sood, B S [Punjabi Univ., Patiala (India). Nuclear Science Labs.

1983-05-21

Integral cross-sections of incoherent interactions of 662 and 1250 keV gamma-rays with L-shell electrons of different elements with 74<=Z<=92 have been measured. The experimental results, when interpreted in terms of photoelectric and Compton interaction cross-sections, are found to agree with theory.