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Sample records for abstract microwave induced

  1. Scanning Microwave Induced Acoustic Tomography

    National Research Council Canada - National Science Library

    Wang, Lihong V

    2001-01-01

    .... Cancerous breast tissues are found to be 2-5 times more strongly absorbing than surrounding normal breast tissues in the microwave, which has been attributed to an increase in bound water and sodium...

  2. Cataracts induced by microwave and ionizing radiation

    International Nuclear Information System (INIS)

    Lipman, R.M.; Tripathi, B.J.; Tripathi, R.C.

    1988-01-01

    Microwaves most commonly cause anterior and/or posterior subcapsular lenticular opacities in experimental animals and, as shown in epidemiologic studies and case reports, in human subjects. The formation of cataracts seems to be related directly to the power of the microwave and the duration of exposure. The mechanism of cataractogenesis includes deformation of heat-labile enzymes, such as glutathione peroxide, that ordinarily protect lens cell proteins and membrane lipids from oxidative damage. Oxidation of protein sulfhydryl groups and the formation of high-molecular-weight aggregates cause local variations in the orderly structure of the lens cells. An alternative mechanism is thermoelastic expansion through which pressure waves in the aqueous humor cause direct physical damage to the lens cells. Cataracts induced by ionizing radiation (e.g., X-rays and gamma rays) usually are observed in the posterior region of the lens, often in the form of a posterior subcapsular cataract. Increasing the dose of ionizing radiation causes increasing opacification of the lens, which appears after a decreasing latency period. Like cataract formation by microwaves, cataractogenesis induced by ionizing radiation is associated with damage to the lens cell membrane. Another possible mechanism is damage to lens cell DNA, with decreases in the production of protective enzymes and in sulfur-sulfur bond formation, and with altered protein concentrations. Until further definitive conclusions about the mechanisms of microwaves and ionizing radiation induced cataracts are reached, and alternative protective measures are found, one can only recommend mechanical shielding from these radiations to minimize the possibility of development of radiation-induced cataracts. 74 references

  3. Abstracts of 15.conference on radio and microwave spectroscopy. RAMIS'93

    International Nuclear Information System (INIS)

    1993-01-01

    Radio- and microwave spectroscopy methods have been used for the study of physico-chemical properties of semiconductor and insulating materials as well as high-T c superconductors. The material microstructure, crystal structure and phase transformation studies have been reported. Also the paramagnetic species induced by radiation have been studied in various chemical and biological systems. The basic investigations on spin relaxation in matrices have been extensively reported

  4. Generation of microwave-induced plasmas in automotive exhaust gas mixtures using pulsed microwave energy.

    Science.gov (United States)

    Destefani, Carlos A; Siores, Elias; Murphy, Anthony B

    2003-01-01

    Microwave energy at 2.45 GHz was applied to a mixture of exhaust gases from a petrol engine at atmospheric pressure. It was found that by pulsing the microwave energy with a 50% duty cycle, the average power required to sustain a microwave-induced plasma discharge was decreased by about 40%. The ratio of absorbed to incident power was unaffected. These findings were confirmed for pulse frequencies from 10 to 300 Hz.

  5. Management of chemotherapy induced diarrhea (abstract)

    International Nuclear Information System (INIS)

    Qureshi, A.M.

    1998-01-01

    Diarrhoea is seen with many tumors and following several chemotherapy regimen esp. those containing 5-fluorouracil and high dose folinic acid it causes debility even death, delays cancer treatment, reduces compliance increases cost. It causes dehydration, renal failure volume depletion. Quality of life is worsened and hospitalization may be needed in multifactorial, with secretion; absorption imbalance due to mucosal damage, necrosis or inflammation. Local infection is set up by opportunistic organism and cell necrosis. The large volume of fluid and electrolytes overwhelms colonic absorptive capacity. Agent usually used for treatment is opioids (such as Diphenoxylate / Loperamide]. Bismuth (for inflammatory diarrhea). NSAIDs or alpha 2-agonists. For optimal management, the cause and severity should be assessed and treatment planned. Advice is given about certain dietary restraints and avoidance of some drugs. Fever, infection, dehydration and electrolyte losses are treated, pain relieved. Diphenoxylate / Loperamide (later is more effective; 4 mg, STAT, then 2mg every 4 hours or even 2 hourly) may be used. It is moderately effective in CID. Octreotide is useful in carcinoid. VIPoma, AIDS idiopathic secretary diarrhea, ileostomy, dumping syndrome. It acts directly on epithelial cells to reduce secretin, motilin pancreatic polypeptide. It slows transit time, reduces fluid and electrolyte secretin, increases absorption of electrolytes. It is effective in 5 FU and high dose chemotherapy with a 90% response rates seen after 3 days treatment. High Dose Chemotherapy and total body irradiation - induced diarrhea usually resolves within 72 hours. (author)

  6. ABSTRACT

    African Journals Online (AJOL)

    University Health Services. Ahmadu Bella University, Zaria, Nigeria. ABSTRACT. Phywieo-chemical methods were used to analyse the commonly used lcualt samples bought from Zaria and Kano local markets. Blood-leadaoncentrations in ltuali ...

  7. Abstract

    African Journals Online (AJOL)

    Francis

    Abstract. Aqueous, methanol and chloroform extracts from the leaves of Ficus religiosa, Thespesia populnea and Hibiscus tiliaceus were completely screened for antibacterial and antifungal activity. The chloroform extract of F. religiosa possessed a broad spectrum of antibacterial activity with a zone of inhibition of 10 to 21 ...

  8. Abstract,

    African Journals Online (AJOL)

    Abstract·. A study was carried out to investigate the effect of overso~ing legumes on ~a~gela~d pe'rtormance in. Shinyanga'region, Tanzania. Four leguminous species namely Centrosema pubescence, Clito-':iii ternatea,. cMacroptilium atropurpureum and Stylosanthes hamata were Qversown in. a"natural ran,geland in a.

  9. Abstract

    Indian Academy of Sciences (India)

    65

    Abstract. For well over three hundred years, the monsoon has been considered to be a gigantic land-sea breeze driven by the land-ocean contrast in surface temperature. In this paper, this hypothesis ..... primary driver of the monsoon in many papers and most textbooks (e.g. Lau and Li, 1984,. Webster 1987a, Meehl 1994, ...

  10. ABSTRACT

    African Journals Online (AJOL)

    Email: jameskigera@yahoo.co.uk. ABSTRACT. Background: Implant orthopaedic surgery is associated with a risk of post operative Surgical Site. Infection (SSI). This can have devastating consequences in the case of arthroplasty. Due to the less than ideal circumstances under which surgery is conducted in Africa, there are ...

  11. Abstract

    African Journals Online (AJOL)

    WORKERS ON THEIR JOB PERFORMANCE IN IMO STATE, NIGERIA. NGOZI OKEREKE AND no. ONU. ABSTRACT. The study focused on the. efl'ect of socioeconomic characteristics of field extension workers on their job performance in.1mo state agricultural development programme, Nigeria. Data was collected with the ...

  12. Abstract

    African Journals Online (AJOL)

    PROF. OLIVER OSUAGWA

    Abstract. Many mathematical models of stochastic dynamical systems were based on the assumption that the drift and volatility coefficients were linear function of the solution. In this work, we arrive at the drift and the volatility by observing the dynamics of change in the selected stocks in a sufficiently small interval t∆ .

  13. ABSTRACT

    African Journals Online (AJOL)

    Dr Obe

    inner forces (bending moments, shearing forces etc) are usually redistributed. Cracks that often appear within the walls of tall buildings during constructions point to this phenomenon. It has also been recognized that foundation engineering is complicated. (1). Also settlement has been accepted as stress induced and time ...

  14. Microwave-Induced Chemotoxicity of Polydopamine-Coated Magnetic Nanocubes

    KAUST Repository

    Julfakyan, Khachatur

    2015-08-06

    Polydopamine-coated FeCo nanocubes (PDFCs) were successfully synthesized and tested under microwave irradiation of 2.45 GHz frequency and 0.86 W/cm2 power. These particles were found to be non-toxic in the absence of irradiation, but gained significant toxicity upon irradiation. Interestingly, no increase in relative heating rate was observed when the PDFCs were irradiated in solution, eliminating nanoparticle (NP)-induced thermal ablation as the source of toxicity. Based on these studies, we propose that microwave-induced redox processes generate the observed toxicity. © 2015 by the authors; licensee MDPI, Basel, Switzerland.

  15. Development of microwave-enhanced spark-induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Ikeda, Yuji; Moon, Ahsa; Kaneko, Masashi

    2010-01-01

    We propose microwave-enhanced spark-induced breakdown spectroscopy with the same measurement and analysis processes as in laser-induced breakdown spectroscopy, but with a different plasma generation mechanism. The size and lifetime of the plasma generated can contribute to increased measurement accuracy and expand its applicability to industrial measurement, such as an exhaust gas analyzer for automobile engine development and its regulation, which has been hard to operate by laser at an engineering evaluation site. The use of microwaves in this application helps lower the cost, reduce the system size, and increase the ease of operation to make it commercially viable. A microwave frequency of 2.45 GHz was used to enhance the volume and lifetime of the plasma at atmospheric condition even at elevated pressure.

  16. A case of seizures induced by abstract reasoning.

    Science.gov (United States)

    Tatsuzawa, Yasutaka; Yoshino, Aihide; Nomura, Soichiro

    2010-04-01

    We describe a case of reflex seizures induced by abstract reasoning but not other cognitive processes. The patient, a 46-year-old man, experienced myoclonic seizures whenever he played shogi (Japanese chess). To identify the critical thought processes responsible for inducing his seizures, we monitored his clinical seizures and epileptiform discharges while he performed comprehensive neuropsychological tests, including the Wechsler Adult Intelligence Scale-Revised (WAIS-R), spatial working memory, mental rotation, and Wisconsin Card Sorting Test (WCST) tasks. A myoclonic seizure occurred only during the WCST. Generalized 3- to 5-Hz spike-and-slow-wave bursts occurred repeatedly during the Block Design subtest of the WAIS-R and the WCST, whereas no discharges occurred during other subtests of the WAIS-R including the calculation, spatial working memory, and mental rotation tasks. These results indicate that abstract reasoning, independent of other cognitive processes, could induce the patient's epileptiform discharges, suggesting that his reflex seizures might be a distinct subtype of nonverbal thinking-induced seizures. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  17. Microwave induced solubility enhancement of poorly water soluble atorvastatin calcium.

    Science.gov (United States)

    Maurya, Durgaprasad; Belgamwar, Veena; Tekade, Avinash

    2010-11-01

    The objective of the present investigation was to enhance the solubility and dissolution rate of atorvastatin calcium (ATR) by a solid dispersion technique using poly(ethylene glycol) 6000 (PEG 6000). Microwave energy was used to prepare an enhanced release dosage form of the poorly water soluble drug ATR with PEG 6000 as a hydrophilic carrier. After the microwave treatment, the drug and hydrophilic polymer get fused together to form a solid dispersion. An in-vivo study was performed to determine the lipid-lowering efficacy (cholesterol, high density lipoprotein and triglyceride) of the solid dispersions using a Triton-induced hypercholesterolemia model in rats. An increase in the solubility of ATR was observed with increasing concentration of PEG 6000. The optimized ratio for preparation of solid dispersions of ATR with PEG 6000 was 1:12 w/w by conventional fusion and the microwave induced fusion method. Differential scanning calorimetry and powder X-ray diffraction studies of the solid dispersions confirmed the conversion of some crystalline ATR into the amorphous form. Scanning electron microscopy images also showed conversion of some crystalline ATR into the amorphous form. The in-vitro study showed that solid dispersions increased the solubility and dissolution rate of ATR, and thus may improve its bioavailability compared with plain ATR. The solid dispersion formulation prepared by the microwave induced fusion method significantly (P<0.05) reduced serum lipid levels in phases I and II (18 h and 24 h) of the Triton test compared with plain ATR. The microwave induced fusion method could be considered as a simple, efficient method to prepare solid dispersions of ATR with significant enhancement of the in-vitro dissolution rate as well as in-vivo activity. © 2010 The Authors. JPP © 2010 Royal Pharmaceutical Society of Great Britain.

  18. Microwave-induced cracking of pyrolytic tars coupled to microwave pyrolysis for syngas production.

    Science.gov (United States)

    Beneroso, D; Bermúdez, J M; Montes-Morán, M A; Arenillas, A; Menéndez, J A

    2016-10-01

    Herein a new process is proposed to produce a syngas-rich gas fraction (>80vol% H2+CO) from biowaste based on microwave heating within two differentiated steps in order to avoid tars production. The first step consists of the microwave pyrolysis of biowaste induced by a char-based susceptor at 400-800°C; tars, char and syngas-rich gas fractions being produced. The tars are then fed into the second step where a portion of the char from the first step is used as a bed material in a 0.3:1wt% ratio. This bed is heated up by microwaves up to 800°C, allowing thermal cracking of tars and additional syngas (>90vol% H2+CO) being then produced. This new concept arises as an alternative technology to the gasification of biowastes for producing syngas with no need for catalysts or gasifying reagents to minimise tars production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Microwave-induced Apoptosis and Cytotoxicity of NK Cells through ERK1/2 Signaling.

    Science.gov (United States)

    Zhao, Li; Li, Jing; Hao, Yan Hui; Gao, Ya Bing; Wang, Shui Ming; Zhang, Jing; Dong, Ji; Zhou, Hong Mei; Liu, Shu Chen; Peng, Rui Yun

    2017-05-01

    To investigate microwave-induced morphological and functional injury of natural killer (NK) cells and uncover their mechanisms. NK-92 cells were exposed to 10, 30, and 50 mW/cm2 microwaves for 5 min. Ultrastructural changes, cellular apoptosis and cell cycle regulation were detected at 1 h and 24 h after exposure. Cytotoxic activity was assayed at 1 h after exposure, while perforin and NKG2D expression were detected at 1 h, 6 h, and 12 h after exposure. To clarify the mechanisms, phosphorylated ERK (p-ERK) was detected at 1 h after exposure. Moreover, microwave-induced cellular apoptosis and cell cycle regulation were analyzed after blockade of ERK signaling by using U0126. Microwave-induced morphological and ultrastructural injury, dose-dependent apoptosis (P microwave exposure. Moreover, significant apoptosis was still detected at 24 h after 50 mW/cm2 microwave exposure (P microwave exposure model, microwaves impaired the cytotoxic activity of NK-92 cells at 1 h and down regulated perforin protein both at 1 h and 6 h after exposure (P microwave-induced apoptosis (P Microwave dose-dependently induced morphological and functional injury in NK-92 cells, possibly through ERK-mediated regulation of apoptosis and perforin expression. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  20. Air breakdown induced by a high-power short-pulse microwave

    International Nuclear Information System (INIS)

    Wakisaka, T.; Yatsuzuka, M.; Nobuhara, S.

    1996-01-01

    At Himeji Institute of Technology, the high power microwaves with the peak power of 20 MW, frequency of 12 GHz and pulse duration of 14 ns have been produced with a virtual cathode oscillator (vircator). These high power microwaves offer new applications in various fields. One problem in laser-triggered lightning experiment is the strong attenuation of laser energy by rain, cloud and laser-produced plasma. Microwaves propagate in thundercloud with small loss, and also are able to irradiate much extensive region of targets. In this paper, the fundamental experiment on the air breakdown induced by high power, short pulse microwaves is reported. The experimental setup of the vircator diode for microwave generation is shown. The typical evolution of diode voltage, electron beam current and microwave emission from the top in the course of time is shown. The experimental setup for microwave-induced air breakdown and the experimental procedure are explained. The results of negative polarity and positive polarity are reported. In the pressure range lower than 150 Torr, microwave-induced breakdown occurred without corona discharge in both polarities. Microwave-induced breakdown occurred more easily in negative polarity than in positive polarity. (K.I.)

  1. Microwave-induced carbon nanotubes catalytic degradation of organic pollutants in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jing; Xue, Shuang; Song, Youtao; Shen, Manli [School of Environment Science, Liaoning University, Shenyang 110036 (China); Zhang, Zhaohong, E-mail: lnuhjhx@163.com [School of Environment Science, Liaoning University, Shenyang 110036 (China); Yuan, Tianxin; Tian, Fangyuan [School of Environment Science, Liaoning University, Shenyang 110036 (China); Dionysiou, Dionysios D., E-mail: dionysios.d.dionysiou@uc.edu [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States)

    2016-06-05

    Highlights: • Microwave-induced CNTs-based catalytic degradation technology is developed. • Microwave catalytic activities of CNTs with different diameters are compared. • Organic pollutants with different structure can be degraded in MW/CNTs system. • The 10–20 nm CNTs shows the higher catalytic activity under MW irradiation. - Abstract: In this study, a new catalytic degradation technology using microwave induced carbon nanotubes (MW/CNTs) was proposed and applied in the treatment of organic pollutants in aqueous solution. The catalytic activity of three CNTs of 10–20 nm, 20–40 nm, and 40–60 nm diameters were compared. The results showed that organic pollutants such as methyl orange (MO), methyl parathion (MP), sodium dodecyl benzene sulfonate (SDBS), bisphenol A (BPA), and methylene blue (MB) in aqueous solution could be degraded effectively and rapidly in MW/CNTs system. CNTs with diameter of 10–20 nm exhibited the highest catalytic activity of the three CNTs under MW irradiation. Further, complete degradation was obtained using 10–20 nm CNTs within 7.0 min irradiation when 25 mL MO solution (25 mg/L), 1.2 g/L catalyst dose, 450 W, 2450 MHz, and pH = 6.0 were applied. The rate constants (k) for the degradation of SDBS, MB, MP, MO and BPA using 10–20 nm CNTs/MW system were 0.726, 0.679, 0.463, 0.334 and 0.168 min{sup −1}, respectively. Therefore, this technology may have potential application for the treatment of targeted organic pollutants in wastewaters.

  2. Using a microwave-induced method to regenerate platinum catalyst

    Directory of Open Access Journals (Sweden)

    Chih-Ju G. Jou

    2017-11-01

    Full Text Available When the catalyst is put under the conditions of microwave energy with oxygen, it absorbs microwave energy and turns the energy into heat to support the combustion process. The oxygen is spread into the catalyst through surface pores which allows coke combustion. The laboratory results show that when air flow rate is at 2 L min−1 and microwave energy is at 450 W with an exposure time of 8 h, the coke removal efficiency was 70% as compared to 15% in the control system (without air. This study provides an innovative technique of using microwave energy to regenerate spent platinum catalysts containing coke.

  3. Optimization of microwave-induced chemical etching for rapid development of neutron-induced recoil tracks in CR-39 detectors

    International Nuclear Information System (INIS)

    Sahoo, G.S.; Tripathy, S.P.; Bandyopadhyay, T.

    2014-01-01

    A systematic investigation is carried out to optimize the recently established microwave-induced chemical etching (MICE) parameters for rapid development of neutron-induced recoil tracks in CR-39 detectors. Several combinations of all available microwave powers with different etching durations were analysed to determine the most suitable etching condition. The etching duration was found to reduce with increasing microwave power and the tracks were observed at about 18, 15, 12, and 6 min for 300, 450, 600 and 900 W of microwave powers respectively compared to a few hours in chemical etching (CE) method. However, for complete development of tracks the etching duration of 30, 40, 50 and 60 min were found to be suitable for the microwave powers of 900, 600, 450 and 300 W, respectively. Temperature profiles of the etchant for all the available microwave powers at different etching durations were generated to regulate the etching process in a controlled manner. The bulk etch rates at different microwave powers were determined by 2 methods, viz., gravimetric and removed thickness methods. A logarithmic expression was used to fit the variation of bulk etch rate with microwave power. Neutron detection efficiencies were obtained for all the cases and the results on track parameters obtained with MICE technique were compared with those obtained from another detector processed with chemical etching. - Highlights: • Microwave-induced chemical etching method is optimized for rapid development of recoil tracks due to neutrons in CR-39 detector. • Several combinations of microwave powers and etching durations are investigated to standardize the suitable etching condition. • Bulk-etch rates are determined for all microwave powers by two different methods, viz. gravimetric and removed thickness method. • The method is found to be simple, effective and much faster compared to conventional chemical etching

  4. Microwave induced fast pyrolysis of scrap rubber tires

    Science.gov (United States)

    Ani, Farid Nasir; Mat Nor, Nor Syarizan

    2012-06-01

    Pyrolysis is the thermal degradation of carbonaceous solid by heat in the absence of oxygen. The feedstocks, such as biomass or solid wastes are heated to a temperature between 400 and 600°C, without introducing oxygen to support the reaction. The reaction produces three products: gas, pyro-fuel oil and char. This paper presents the techniques of producing pyro-oil from waste tires, as well as investigation of the fuel properties suitable for diesel engine applications. In this study, microwave heating technique is employed to pyrolyse the used rubber tires into pyro-oil. Thermal treatment of as received used rubber tires is carried out in a modified domestic microwave heated fixed bed technology. It has been found that, rubber tires, previously used by various researchers, are poor microwave absorbers. Studies have shown that an appropriate microwave-absorbing material, such as biomass char or activated carbon, could be added to enhance the pyrolysis process; thus producing the pyro-oil. The characteristics of pyro-oil, as well as the effect of microwave absorber on its yield, are briefly described in this paper. The temperature profiles during the microwave heating process are also illustratively emphasized. The study provides a means of converting scrap tires into pyro-oil and pyrolytic carbon black production. The proposed microwave thermal conversion process therefore has the potentials of substantially saving time and energy.

  5. Air breakdown induced by a high-power short-pulse microwave

    International Nuclear Information System (INIS)

    Wakisaka, T.; Yatsuzuka, M.; Nobuhara, S.

    1996-01-01

    Air breakdown induced by a high-power short-pulse microwave in the pressure range from 100 to 760 Torr was studied experimentally. The high-power microwaves with the peak power of 20 MW, frequency of 12 GHz and pulse duration of 14 ns was irradiated to a pair of needle and plane electrodes biased at the potential less than the breakdown voltage. The gap separation between the needle and plane electrodes was 1.5 cm. Microwave-induced breakdowns occurred at the pressure range from 150 to 760 Torr for negative potential and from 150 to 350 Torr for positive polarity at the presence of corona discharges. At the pressure range less than 150 Torr, the microwave-induced breakdown occurred without corona discharge at both polarities. (author). 5 figs., 4 refs

  6. Cellular neoplastic transformation induced by 916 MHz microwave radiation.

    Science.gov (United States)

    Yang, Lei; Hao, Dongmei; Wang, Minglian; Zeng, Yi; Wu, Shuicai; Zeng, Yanjun

    2012-08-01

    There has been growing concern about the possibility of adverse health effects resulting from exposure to microwave radiations, such as those emitted by mobile phones. The purpose of this study was to investigate the cellular neoplastic transformation effects of electromagnetic fields. 916 MHz continuous microwave was employed in our study to simulate the electromagnetic radiation of mobile phone. NIH/3T3 cells were adopted in our experiment due to their sensitivity to carcinogen or cancer promoter in environment. They were divided randomly into one control group and three microwave groups. The three microwave groups were exposed to 916 MHz EMF for 2 h per day with power density of 10, 50, and 90 w/m(2), respectively, in which 10 w/m(2) was close to intensity near the antenna of mobile phone. The morphology and proliferation of NIH/3T3 cells were examined and furthermore soft agar culture and animal carcinogenesis assay were carried out to determine the neoplastic promotion. Our experiments showed NIH/3T3 cells changed in morphology and proliferation after 5-8 weeks exposure and formed clone in soft agar culture after another 3-4 weeks depending on the exposure intensity. In the animal carcinogenesis study, lumps developed on the back of SCID mice after being inoculated into exposed NIH/3T3 cells for more than 4 weeks. The results indicate that microwave radiation can promote neoplastic transformation of NIH/3T3cells.

  7. Microwave-induced combustion of crude oil for further rare earth elements determination by USN–ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, J.S.F. [Departamento de Química Inorgânica, Universidade Federal do Rio Grande do Sul, 97105-900 Porto Alegre, RS (Brazil); Pereira, L.S.F.; Mello, P.A. [Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil); Guimarães, R.C.L.; Guarnieri, R.A.; Fonseca, T.C.O. [CENPES/PETROBRAS, 21941-945 Rio de Janeiro, RJ (Brazil); Flores, E.M.M., E-mail: ericommf@gmail.com [Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil)

    2014-09-24

    Highlights: • Microwave-induced combustion was applied for light and heavy crude oils digestion. • It was feasible to determine all the REEs in heavy crude oil by ICP-MS. • Only diluted acid solutions were used in agreement to green chemistry recommendations. - Abstract: A procedure for light and heavy crude oils digestion by microwave-induced combustion (MIC) is proposed for the first time for further rare earth elements (REE) determination by inductively coupled plasma mass spectrometry (ICP-MS) equipped with an ultrasonic nebulizer (USN). Samples of crude oil (API density of 10.8–23.5, up to 250 mg) were inserted in polycarbonate capsules and combusted using 20 bar of oxygen and 50 μL of 6 mol L{sup −1} ammonium nitrate as igniter. Nitric acid solutions (1–14.4 mol L{sup −1}) were evaluated for analyte absorption and a reflux step was applied after combustion (5 min of microwave irradiation at 1400 W) in order to achieve better analyte recoveries. Accuracy was evaluated using a spiked sample and also by comparison of results obtained by microwave-assisted digestion combined to ultraviolet radiation (MW–UV) and by neutron activation analysis (NAA). Using 3 mol L{sup −1} HNO{sub 3}, quantitative recoveries (better than 97%) were obtained for all analytes. Blank values were always negligible. Agreement was higher than 96% for La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y by comparison of results with those obtained by MW–UV and by NAA (only for La, Ce, Nd, Sm, and Yb). Residual carbon content in digests using MIC was always below 1%. As an advantage over conventional procedures for crude oil digestion, using MIC, it was possible to use diluted acid as absorbing solution, obtaining better limits of detection and avoiding interferences in REE determination by USN–ICP-MS.

  8. Noise-modulated-microwave-induced response in snail neurons

    Energy Technology Data Exchange (ETDEWEB)

    Lin, J.C.; Arber, S.L.

    1983-01-01

    Helix aspersa neurons were irradiated with noise-amplitude-modulated microwaves (carrier frequency 2450 MHz, 20% AM, 0-20 kHz, specific absorption rate 6.8 and 14.4 mW/g). It was found that such an exposure caused an appearance of high frequency bursts and a rise in membrane resistance.

  9. Microwave oven-induced decalcification at varying temperatures: A ...

    African Journals Online (AJOL)

    This study was designed to evaluate the effect of decalcifying fluid types on bone tissue architecture and its staining properties following decalcification at varying temperatures. A decalcification methodology using Golding and Stewards (GS) fluid, and Jenkings fluid (JK), and a modern household microwave oven to ...

  10. Microwave-induced nonequilibrium temperature in a suspended carbon nanotube

    NARCIS (Netherlands)

    Hortensius, H.L.; Öztürk, A.; Zeng, P.; Driessen, E.F.C.; Klapwijk, T.M.

    2012-01-01

    Antenna-coupled suspended single carbon nanotubes exposed to 108?GHz microwave radiation are shown to be selectively heated with respect to their metal contacts. This leads to an increase in the conductance as well as to the development of a power-dependent DC voltage. The increased conductance

  11. Low intensity microwave radiation induced oxidative stress, inflammatory response and DNA damage in rat brain.

    Science.gov (United States)

    Megha, Kanu; Deshmukh, Pravin Suryakantrao; Banerjee, Basu Dev; Tripathi, Ashok Kumar; Ahmed, Rafat; Abegaonkar, Mahesh Pandurang

    2015-12-01

    Over the past decade people have been constantly exposed to microwave radiation mainly from wireless communication devices used in day to day life. Therefore, the concerns over potential adverse effects of microwave radiation on human health are increasing. Until now no study has been proposed to investigate the underlying causes of genotoxic effects induced by low intensity microwave exposure. Thus, the present study was undertaken to determine the influence of low intensity microwave radiation on oxidative stress, inflammatory response and DNA damage in rat brain. The study was carried out on 24 male Fischer 344 rats, randomly divided into four groups (n=6 in each group): group I consisted of sham exposed (control) rats, group II-IV consisted of rats exposed to microwave radiation at frequencies 900, 1800 and 2450 MHz, specific absorption rates (SARs) 0.59, 0.58 and 0.66 mW/kg, respectively in gigahertz transverse electromagnetic (GTEM) cell for 60 days (2h/day, 5 days/week). Rats were sacrificed and decapitated to isolate hippocampus at the end of the exposure duration. Low intensity microwave exposure resulted in a frequency dependent significant increase in oxidative stress markers viz. malondialdehyde (MDA), protein carbonyl (PCO) and catalase (CAT) in microwave exposed groups in comparison to sham exposed group (pmicrowave exposed groups (pmicrowave exposed animal (pmicrowave exposed groups as compared to their corresponding values in sham exposed group (pmicrowave radiation induces oxidative stress, inflammatory response and DNA damage in brain by exerting a frequency dependent effect. The study also indicates that increased oxidative stress and inflammatory response might be the factors involved in DNA damage following low intensity microwave exposure. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Microwave-induced co-processing of coal and biomass

    OpenAIRE

    Yan, Jie-Feng

    2015-01-01

    Pyrolysis is an attractive alternative for the conversion of solid fuels to valuable chemicals and bio-fuels. In order to obtain more H2 and syngas from pyrolysis of coal and biomass, microwave has been adopted to enhance the co-pyrolysis of coal and biomass, which has been investigated systematically in this study. Firstly, conventional pyrolysis of coal and biomass was carried out using a vertical tube furnace. Characterizations of pyrolytic gas, liquid and solid products were conducted...

  13. Mechanisms of Microwave Induced Damage in Biologic Materials

    Science.gov (United States)

    1988-01-25

    variability on strain JG44 of saccharomyces cerviciae cells suspended in yeast extractII peptone in dextrose ( YPD ) solution. I TABLE 1.9 Exp.ID Freq...Measurements A primary requirement of the applicator design was to allow microwave irradiation of mammalian cultured cells in an aqueous medium at a...due to poor sample insulation. ii: Irradiate sample tube filled with cells in suspension, with nutrient medium , and with DI water at the same power

  14. Autophagy mediates the degradation of synaptic vesicles: A potential mechanism of synaptic plasticity injury induced by microwave exposure in rats.

    Science.gov (United States)

    Hao, Yanhui; Li, Wenchao; Wang, Hui; Zhang, Jing; Yu, Chao; Tan, Shengzhi; Wang, Haoyu; Xu, Xinping; Dong, Ji; Yao, Binwei; Zhou, Hongmei; Zhao, Li; Peng, Ruiyun

    2018-02-03

    To explore how autophagy changes and whether autophagy is involved in the pathophysiological process of synaptic plasticity injury caused by microwave radiation, we established a 30 mW/cm 2 microwave-exposure in vivo model, which caused reversible injuries in rat neurons. Microwave radiation induced cognitive impairment in rats and synaptic plasticity injury in rat hippocampal neurons. Autophagy in rat hippocampal neurons was activated following microwave exposure. Additionally, we observed that synaptic vesicles were encapsulated by autophagosomes, a phenomenon more evident in the microwave-exposed group. Colocation of autophagosomes and synaptic vesicles in rat hippocampal neurons increased following microwave exposure. microwave exposure led to the activation of autophagy in rat hippocampal neurons, and excessive activation of autophagy might damage synaptic plasticity by mediating synaptic vesicle degradation. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Effects of coupling efficiency on atomic spectrometry with a microwave-induced plasma

    International Nuclear Information System (INIS)

    Burns, B.A.

    1987-01-01

    The atmospheric-pressure, microwave-induced argon plasma from a TM 010 mode cavity is made nearly 100% efficient by matching the impedance of the generator to the impedance of the load. The impedance match is achieved by increasing the size of the coupling probe and by varying cavity permittivity and microwave probe position to lower the reflected power to nearly zero watts. The efficient microwave plasma is capable of operating with as little as 5 watts of power, producing plasma plumes of 16 cm in length when operated at 100 watts, reflecting almost no measurable power, and generating virtually no cavity heat. With plasma power known for all operating conditions, experiments were performed to help create a model for the efficient operation of the cavity at all input powers. This model was used to correlate the plasma electron density with plasma power for a further fundamental understanding of the microwave-induced plasma. The model for the efficient microwave plasma is related to the changes in cavity E-field intensity with changes in plasma electron production. The model describes the flow of power from the generator to the plasma and allows correlation of observed phenomena, i.e., plasma electron density and analyte emission intensity, with plasma power

  16. A review of microwave-induced thermoacoustic imaging: Excitation source, data acquisition system and biomedical applications

    Directory of Open Access Journals (Sweden)

    Yongsheng Cui

    2017-07-01

    Full Text Available Microwave-induced thermoacoustic imaging (TAI is a noninvasive modality based on the differences in microwave absorption of various biological tissues. TAI has been extensively researched in recent years, and several studies have revealed that TAI possesses advantages such as high resolution, high contrast, high imaging depth and fast imaging speed. In this paper, we reviewed the development of the TAI technique, its excitation source, data acquisition system and biomedical applications. It is believed that TAI has great potential applications in biomedical research and clinical study.

  17. Neural Cell Apoptosis Induced by Microwave Exposure Through Mitochondria-dependent Caspase-3 Pathway

    Science.gov (United States)

    Zuo, Hongyan; Lin, Tao; Wang, Dewen; Peng, Ruiyun; Wang, Shuiming; Gao, Yabing; Xu, Xinping; Li, Yang; Wang, Shaoxia; Zhao, Li; Wang, Lifeng; Zhou, Hongmei

    2014-01-01

    To determine whether microwave (MW) radiation induces neural cell apoptosis, differentiated PC12 cells and Wistar rats were exposed to 2.856GHz for 5min and 15min, respectively, at an average power density of 30 mW/cm2. JC-1 and TUNEL staining detected significant apoptotic events, such as the loss of mitochondria membrane potential and DNA fragmentation, respectively. Transmission electron microscopy and Hoechst staining were used to observe chromatin ultrastructure and apoptotic body formation. Annexin V-FITC/PI double staining was used to quantify the level of apoptosis. The expressions of Bax, Bcl-2, cytochrome c, cleaved caspase-3 and PARP were examined by immunoblotting or immunocytochemistry. Caspase-3 activity was measured using an enzyme-linked immunosorbent assay. The results showed chromatin condensation and apoptotic body formation in neural cells 6h after microwave exposure. Moreover, the mitochondria membrane potential decreased, DNA fragmentation increased, leading to an increase in the apoptotic cell percentage. Furthermore, the ratio of Bax/Bcl-2, expression of cytochrome c, cleaved caspase-3 and PARP all increased. In conclusion, microwave radiation induced neural cell apoptosis via the classical mitochondria-dependent caspase-3 pathway. This study may provide the experimental basis for further investigation of the mechanism of the neurological effects induced by microwave radiation. PMID:24688304

  18. Groundwater-abstraction induced land subsidence and groundwater regulation in the North China Plain

    OpenAIRE

    Guo, H.; Wang, L.; Cheng, G.; Zhang, Z.

    2015-01-01

    Land subsidence can be induced when various factors such as geological, and hydrogeological conditions and intensive groundwater abstraction combine. The development and utilization of groundwater in the North China Plain (NCP) bring great benefits, and at the same time have led to a series of environmental and geological problems accompanying groundwater-level declines and land subsidence. Subsidence occurs commonly in the NCP and analyses show that multi-layer aquifer syst...

  19. Naltrexone pretreatment blocks microwave-induced changes in central cholinergic receptors

    Energy Technology Data Exchange (ETDEWEB)

    Lai, H.; Carino, M.A.; Wen, Y.F.; Horita, A.; Guy, A.W. (Univ. of Washington School of Medicine, Seattle (USA))

    1991-01-01

    Repeated exposure of rats to pulsed, circularly polarized microwaves (2,450-MHz, 2-microseconds pulses at 500 pps, power density 1 mW/cm2, at an averaged, whole-body SAR of 0.6 W/kg) induced biphasic changes in the concentration of muscarinic cholinergic receptors in the central nervous system. An increase in receptor concentration occurred in the hippocampus of rats subjected to ten 45-min sessions of microwave exposure, whereas a decrease in concentration was observed in the frontal cortex and hippocampus of rats exposed to ten 20-min sessions. These findings, which confirm earlier work in the authors' laboratory, were extended to include pretreatment of rats with the narcotic antagonist naltrexone (1 mg/kg, IP) before each session of exposure. The drug treatment blocked the microwave-induced changes in cholinergic receptors in the brain. These data further support the authors' hypothesis that endogenous opioids play a role in the effects of microwaves on central cholinergic systems.

  20. Effects of Tenghuanglin on injury to splenic lymphocyte induced by microwave radiation in rats

    Directory of Open Access Journals (Sweden)

    Qiong MA

    2015-01-01

    Full Text Available Objective To observe the effects of Tenghuanglin (THL on injury to peripheral T and B lymphocytes induced by microwave radiation in rats, and explore the protective effects of THL against derangement of immunity in rat injury induced by microwave irradiation and its mechanism. Methods Eighty clean male SD rats were randomly divided into normal group (CON group, radiation group (RAD group, AduoLa Fuzhenglin (ADL treatment group and THL treatment group, with 20 rats in each group. Before radiation, rats in ADL group and THL group were treated with ADL and THL respectively by gavage once per day for 7 days. Then, whole body of the rats was respectively exposed to 30 mW/cm2 microwave for 15 min. Rats in CON group were shamradiated. The changes in splenic CD3+, CD4+, CD8+ T lymphocyte subsets and CD45RA+ B lymphocyte subset were analyzed 7 and 14 days after radiation. Results Seven days after radiation, the splenic coefficient of RAD group was lower than that of CON group and THL group (P0.05. The CD45RA+ B cell proportion of RAD group was lower than those of CON group and ADL group 7 days after radiation (P0.05. Conclusions The splenic T and B lymphocytes subsets decrease significantly at the early stage after microwave radiation in rats. Because of the rapid decrease in CD4+ T cell proportion, decreased CD4/CD8 ratio could lead to immune imbalance. Preventive treatment with THL could increase the T and B lymphocyte proportions and improve the CD4/CD8 ratio in rats after microwave radiation. DOI: 10.11855/j.issn.0577-7402.2014.12.14

  1. Catalytic effect of transition metals on microwave-induced degradation of atrazine in mineral micropores.

    Science.gov (United States)

    Hu, Erdan; Cheng, Hefa

    2014-06-15

    With their high catalytic activity for redox reactions, transition metal ions (Cu(2+) and Fe(3+)) were exchanged into the micropores of dealuminated Y zeolites to prepare effective microporous mineral sorbents for sorption and microwave-induced degradation of atrazine. Due to its ability to complex with atrazine, loading of copper greatly increased the sorption of atrazine. Atrazine sorption on iron-exchanged zeolites was also significantly enhanced, which was attributed to the hydrolysis of Fe(3+) polycations in mineral micropores and electrostatic interactions of protonated atrazine molecules with the negatively charged pore wall surface. Copper and iron species in the micropores also significantly accelerated degradation of the sorbed atrazine (and its degradation intermediates) under microwave irradiation. The catalytic effect was attributed to the easy reducibility and high oxidation activity of Cu(2+) and Fe(3+) species stabilized in the micropores of the zeolites. It was postulated that the surface species of transition metals (monomeric Cu(2+), Cu(2+)-O-Cu(2+) complexes, FeO(+), and dinuclear Fe-O-Fe-like species) in the mineral micropores were thermally activated under microwave irradiation, and subsequently formed highly reactive sites catalyzing oxidative degradation of atrazine. The transition metal-exchanged zeolites, particularly the iron-exchanged ones, were relatively stable when leached under acidic conditions, which suggests that they are reusable in sorption and microwave-induced degradation. These findings offer valuable insights on designing of effective mineral sorbents that can selectively uptake atrazine from aqueous solutions and catalyze its degradation under microwave irradiation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Effect of superposed electromagnetic noise on DNA damage of lens epithelial cells induced by microwave radiation.

    Science.gov (United States)

    Yao, Ke; Wu, Wei; Yu, Yibo; Zeng, Qunli; He, Jiliang; Lu, Deqiang; Wang, Kaijun

    2008-05-01

    To investigate the influence of the 1.8-GHz radiofrequency fields (RFs) of the Global System for Mobile Communications on DNA damage, intracellular reactive oxygen species (ROS) formation, cell cycle, and apoptosis in human lens epithelial cells (hLECs) and whether the effects induced by RF could be blocked by superposing of electromagnetic noise. After 24-hour intermittent exposure at the specific absorption rate of 1 W/kg, 2 W/kg, 3 W/kg, and 4 W/kg, the DNA damage of hLECs was examined by alkaline comet assay and immunofluorescence microscope detection of the phosphorylated form of histone variant H2AX (gammaH2AX) foci, respectively. ROS production was quantified by the fluorescent probe 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA). Cell cycle and cell apoptosis were determined by flow cytometry. DNA damage examined by alkaline comet assay was significantly increased after 3 W/kg and 4 W/kg radiation (P radiation (P microwave radiation and sham exposure groups (P > 0.05). All the effects mentioned were blocked when the RF was superposed with 2 muT electromagnetic noise. Microwave radiation induced hLEC DNA damage after G(0)/G(1) arrest does not lead to cell apoptosis. The increased ROS observed may be associated with DNA damage. Superposed electromagnetic noise blocks microwave radiation-induced DNA damage, ROS formation, and cell cycle arrest.

  3. Microwave detector

    Science.gov (United States)

    Meldner, H.W.; Cusson, R.Y.; Johnson, R.M.

    1985-02-08

    A microwave detector is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite produces a magnetization field flux that links a B-dot loop. The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

  4. Microwave-induced Bismuth Salts-mediated Synthesis of Molecules of Medicinal Interests.

    Science.gov (United States)

    Bandyopadhyay, Debasish; Chavez, Ashlee; Banik, Bimal K

    2017-01-01

    Bismuth salts-mediated reactions have become a powerful tool for the synthesis of diverse medicinally-significant compounds because of their low-toxicity (non-toxic) and Lewis acidic capacity. In fact, LD50 of bismuth nitrate is lower than table salt. On the other hand, microwave-induced chemical synthesis is considered as a major greener route in modern chemistry. A total of 139 publications (including a few authentic web links) have been reviewed mainly to discuss bismuth salts-induced electrophilic aromatic substitution, protection-deprotection chemistry of carbonyl compounds, enamination, oxidation, carbohydrate chemistry, hydrolysis, addition-elimination route, Paal-Knorr reaction, Clauson-kaas synthesis, Michael addition, aza-Michael addition, Hantzsch reaction, Biginelli reaction, Ferrier rearrangement, Pechmann condensation, Diels-Alder and aza-Diels- Alder reactions, as well as effects of microwave irradiation in a wide range of chemical transformations. Bismuth salts-mediated reactions are developed for the synthesis of diverse organic molecules of medicinal significance. Reactions conducted with bismuth salts are environmentally benign, economical, rapid and high yielding. Microwave irradiation has accelerated these reactions significantly. It is believed that bismuth salts released corresponding acids in the media during the reaction. However, a coordination of bismuth salt to the electronegative atom is also observed in the NMR study. Bismuth has much less control (less attractive forces) over anions (for example, halides, nitrate, sulfate and triflates) compared to alkali metals. Therefore, it forms weak bond with electronegative atoms more readily and facilitates the reactions significantly. Many products obtained via bismuth salts-mediated reactions are medicinally active or intermediate for the synthesis of biologically active molecules including antifungal, anti-parasitic, anticancer and antibacterial agents, as well as agents to prevent

  5. The compound Chinese medicine "Kang Fu Ling" protects against high power microwave-induced myocardial injury.

    Directory of Open Access Journals (Sweden)

    Xueyan Zhang

    Full Text Available BACKGROUND: The prevention and treatment of Microwave-caused cardiovascular injury remains elusive. This study investigated the cardiovascular protective effects of compound Chinese medicine "Kang Fu Ling" (KFL against high power microwave (HPM-induced myocardial injury and the role of the mitochondrial permeability transition pore (mPTP opening in KFL protection. METHODS: Male Wistar rats (100 were divided into 5 equal groups: no treatment, radiation only, or radiation followed by treatment with KFL at 0.75, 1.5, or 3 g/kg/day. Electrocardiography was used to Electrophysiological examination. Histological and ultrastructural changes in heart tissue and isolated mitochondria were observed by light microscope and electron microscopy. mPTP opening and mitochondrial membrane potential were detected by confocal laser scanning microscopy and fluorescence analysis. Connexin-43 (Cx-43 and endothelial nitric oxide synthase (eNOS were detected by immunohistochemistry. The expression of voltage-dependent anion channel (VDAC was detected by western blotting. RESULTS: At 7 days after radiation, rats without KFL treatment showed a significantly lower heart rate (P<0.01 than untreated controls and a J point shift. Myocyte swelling and rearrangement were evident. Mitochondria exhibited rupture, and decreased fluorescence intensity, suggesting opening of mPTP and a consequent reduction in mitochondrial membrane potential. After treatment with 1.5 g/kg/day KFL for 7 d, the heart rate increased significantly (P<0.01, and the J point shift was reduced flavorfully (P<0.05 compared to untreated, irradiated rats; myocytes and mitochondria were of normal morphology. The fluorescence intensities of dye-treated mitochondria were also increased, suggesting inhibition of mPTP opening and preservation of the mitochondrial membrane potential. The microwave-induced decrease of Cx-43 and VDAC protein expression was significantly reversed. CONCLUSION: Microwave radiation can

  6. Groundwater-abstraction induced land subsidence and groundwater regulation in the North China Plain

    Directory of Open Access Journals (Sweden)

    H. Guo

    2015-11-01

    Full Text Available Land subsidence can be induced when various factors such as geological, and hydrogeological conditions and intensive groundwater abstraction combine. The development and utilization of groundwater in the North China Plain (NCP bring great benefits, and at the same time have led to a series of environmental and geological problems accompanying groundwater-level declines and land subsidence. Subsidence occurs commonly in the NCP and analyses show that multi-layer aquifer systems with deep confined aquifers and thick compressible clay layers are the key geological and hydrogeological conditions responsible for its development in this region. Groundwater overdraft results in aquifer-system compaction, resulting in subsidence. A calibrated, transient groundwater-flow numerical model of the Beijing plain portion of the NCP was developed using MODFLOW. According to available water supply and demand in Beijing plain, several groundwater regulation scenarios were designed. These different regulation scenarios were simulated with the groundwater model, and assessed using a multi-criteria fuzzy pattern recognition model. This approach is proven to be very useful for scientific analysis of sustainable development and utilization of groundwater resources. The evaluation results show that sustainable development of groundwater resources may be achieved in Beijing plain when various measures such as control of groundwater abstraction and increase of artificial recharge combine favourably.

  7. Microwave-induced titanate nanotubes and the corresponding behaviour after thermal treatment

    International Nuclear Information System (INIS)

    Ou, H H; Lo, S L; Liou, Y H

    2007-01-01

    This study attempts to survey the influence of microwave irradiation on the characterizations of titanate nanotubes (TNTs) synthesized by microwave hydrothermal treatment (M-H treatment). Based on the performance of specific surface areas determined by the classic Brunauer-Emmett-Teller method (S BET ), TNTs synthesized at 130 deg. C for 1.5 h with and without 400 W irradiation presented S BET values of 256 and 76 m 2 g -1 , respectively. The result indicates that the formation kinetics of TNTs is significantly enhanced by M-H treatment. The microwave-induced TNTs are preferentially assigned for Na x H 2-x Ti 3 O 7 structure and the Na/H ratio appreciably increases with higher irradiation power. Regarding the behaviour of TNTs after thermal treatment, TNTs synthesized under 70 W presented anatase phase at 500 deg. C through rearrangement and restacking of [TiO 6 ]. Anatase-to-rutile transformation subsequently occurred at 700 deg. C. TNTs synthesized under 400 and 700 W presented a rod shape at 700 deg. C. The rod shape mainly comprise of Na 2 Ti 6 O 13 of which the (Ti 3 O 7 ) 2- layers with the topotactical connection proceed to form (Ti 6 O 13 ) 2- along the [110] direction during the thermal process

  8. Focused microwave-induced combustion: a new technique for sample digestion.

    Science.gov (United States)

    Mesko, Márcia F; Pereira, Juliana S F; Moraes, Diogo P; Barin, Juliano S; Mello, Paola A; Paniz, José Neri G; Nóbrega, Joaquim A; Korn, Maria G A; Flores, Erico M M

    2010-03-01

    A procedure for sample digestion based on focused microwave-induced combustion (FMIC) is proposed. This system was developed using a commercial focused microwave oven with a lab-made quartz sample holder and a modified glass vessel. Oxygen flow was used to start and support the combustion. A botanical sample was used to evaluate the operational conditions for further Al, Ba, Ca, Fe, Mg, Mn, Sr, and Zn determination by inductively coupled plasma optical emission spectrometry. Pelletized samples were positioned on the quartz holder, and 50 microL of 6 mol L(-1) NH(4)NO(3) solution was added as igniter. Combustion was completed in less than 2 min, and the temperature was higher than 950 degrees C. The use of a reflux step, the position of sample holder inside the vessel, sample mass, ignition and combustion time, oxygen flow rate, and condenser type were evaluated. Results were compared with those obtained by focused microwave-assisted wet digestion and by high pressure microwave-assisted wet digestion. Agreement of 95-103% was obtained for certified reference materials digested by FMIC (reflux step with 10 mL of 4 mol L(-1) HNO(3)). With the proposed procedure, a complete sample decomposition (residual carbon content lower than 0.5%) was achieved with low consumption of reagents as only 10 mL of diluted nitric acid was necessary. Low relative standard deviation (lower than 3.8%) was observed and high amount of sample (up to 1500 mg) could be digested that allowed lower limits of detection.

  9. Microwave-induced synthesis of highly dispersed gold nanoparticles within the pore channels of mesoporous silica

    International Nuclear Information System (INIS)

    Gu Jinlou; Fan Wei; Shimojima, Atsushi; Okubo, Tatsuya

    2008-01-01

    Highly dispersed gold nanoparticles have been incorporated into the pore channels of SBA-15 mesoporous silica through a newly developed strategy assisted by microwave radiation (MR). The sizes of gold are effectively controlled attributed to the rapid and homogeneous nucleation, simultaneous propagation and termination of gold precursor by MR. Diol moieties with high dielectric and dielectric loss constants, and hence a high microwave activation, were firstly introduced to the pore channels of SBA-15 by a simple addition reaction between amino group and glycidiol and subsequently served as the reduction centers for gold nanoparticles. Extraction of the entrapped gold from the nanocomposite resulted in milligram quantities of gold nanoparticles with low dispersity. The successful assembly process of diol groups and formation of gold nanoparticles were monitored and tracked by solid-state NMR and UV-vis measurements. Characterization by small angle X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicated that the incorporation of gold nanoparticles would not breakup the structural integrity and long-range periodicity of SBA-15. The gold nanoparticles had a narrow size distribution with diameters in the size range of 5-10 nm through TEM observation. The average particles size is 7.9 nm via calculation by the Scherrer formula and TEM measurements. Nitrogen adsorption and desorption isotherms gave further evidence that the employed method was efficient and gold nanoparticles were successfully incorporated into the pore channels of SBA-15. - Graphical abstract: A facile and novel strategy has been developed to incorporate gold nanoparticles into the pore channels of mesoporous SBA-15 assisted by microwave radiation (MR) with mild reaction condition and rapid reaction speed. Due to the rapid and homogeneous nucleation, simultaneous propagation and termination by MR, the size of gold nanoparticles are effectively controlled

  10. Effect of remote field electromagnetic boundary conditions on microwave-induced plasma torches

    Science.gov (United States)

    Jimenez-Diaz, M.; van Dijk, J.; van der Mullen, J. J. A. M.

    2011-04-01

    A flexible versatile electromagnetic model constructed with the PLASIMO platform is employed to explore electromagnetic features of microwave-induced plasma torches. The bases, formed by a full-vector formulation of the Maxwell equations, provide the possibility to formulate the boundary conditions in a natural way. Together with the use of a direct matrix solver this gives a convergence speed-up of more than a factor of 100 when compared with a scalar formulation on an azimuthal magnetic field that uses an iterative solver. As a result, this electromagnetic model is ready to act in future studies as part of the self-consistent description of plasma-electromagnetic coupling. With the electromagnetic model three types of configuration were studied: the closed, semi-open and open configurations, all three based on the same simplified model plasmas. It is found that the closed configuration, acting as a cavity for which (de)tuning is extremely sensitive for the plasma conditions, is less suitable for applications in which changes in plasma compositions can be expected. The semi-open configuration can be seen as a model for the practice often used in laboratories to place microwave-induced plasma torches in a grid that aims at protecting the environment against microwave electromagnetic radiation. Calculations show that this is good practice provided the radius of this cylindrical grid is in the order of 90 mm. For the most often used configuration, the open version, we found that the power balance as expressed by the coefficients of absorption, transmission and reflection depends on the electron density of the plasma. The reason is that the plasma acts as an antenna, which converts the electromagnetic waves from the coaxial structure to that of the expansion region, and that this antenna function depends on the electron density. The influence of various other antenna elements is investigated as well.

  11. Protective effects of Tenghuanglin against memory and sperm injury induced by microwave radiation in rats

    Directory of Open Access Journals (Sweden)

    Qiong MA

    2016-09-01

    Full Text Available Objective  To observe the protective effects of Chinese herbal compound Tenghuanglin (THL against memory and sperm damage induced by microwave radiation in rats. Methods  Forty male SD rats were randomly divided into normal control group, radiation group, AduoLaFuzhenglin treatment (ADL group and THL treatment (THL group (10 in each. Before radiation, rats in ADL and THL groups were treated with AduoLaFuzhenglin (12g•kg-1•d-1 and THL (1g•kg-1•d-1 respectively by intragastric administration once per day for 7 days. Then, the rats in radiation, ADL and THL groups were exposed to 30mW/cm2 microwave once for 15min, and rats in normal group received sham-radiation. Morris water maze was adopted to detect the learning and memory function of rats 1-6 days after radiation, and the changes of sperm motility in rats were observed on day 7 post-radiation. Results  Morris water maze tests showed that the escape latency was significantly shorter in ADL group and THL group than in RAD group on day 2-6 after withdrawal (P<0.05. On day 6 after withdrawal, the escape latency in THL group was significantly shorter than that in ADL group (P<0.05. The results of sperm motility assay showed that, compared with control group, the sperm motility in radiation group significantly decreased on day 7 after radiation, for instance, the proportion of sperm in grade A significantly decreased (P<0.05, while the proportion of sperm in grade D and grade C significantly increased (P<0.05. Compared with radiation and ADL group, the proportion of sperm in grade A significantly increased in THL group (P<0.05, while the proportion of sperm in grade D and grade C significantly decreased (P<0.05. Conclusions  Microwave radiation can lead to the learning and memory injury and significant decrement in sperm activity in rats. The preventive administration of traditional Chinese medicine THL can significantly attenuate the injuries of learning and memory ability and sperm

  12. A system to investigate the remediation of organic vapors using microwave-induced plasma with fluidized carbon granules

    International Nuclear Information System (INIS)

    Dawson, Elizabeth A.; Parkes, Gareth M. B.; Bond, Gary; Mao, Runjie

    2009-01-01

    This article describes a system to investigate the parameters for the remediation of organic vapors using microwave-induced plasma on fluidized carbon granules. The system is based on a single mode microwave apparatus with a variable power (2.45 GHz) generator. Carbon granules are fluidized in a silica tube situated in the sample section of a waveguide incorporating two additional ports to allow plasma intensity monitoring using a light sensor and imaging with a digital camera. A fluoroptic probe is used for in situ measurement of the carbon granule temperature, while the effluent gas temperature is measured with a thermocouple situated in the silica tube outside the cavity. Data acquisition and control software allow experiments using a variety of microwave power regimes while simultaneously recording the light intensity of any plasma generated within the carbon bed, together with its temperature. Evaluation using two different granular activated carbons and ethyl acetate, introduced as a vapor into the fluidizing air stream at a concentration of 1 ppm, yielded results which indicated that significant destruction of ethyl acetate, as monitored using a mass spectrometer, was achieved only with the carbon granules showing high plasma activity under pulsed microwave conditions. The system is therefore suitable for comparison of the relative microwave activities of various activated carbon granules and their performance in microwave remediation and regeneration.

  13. Detection of Low Level Microwave Radiation Induced Deoxyribonucleic Acid Damage Vis-à-vis Genotoxicity in Brain of Fischer Rats

    Science.gov (United States)

    Deshmukh, Pravin Suryakantrao; Megha, Kanu; Banerjee, Basu Dev; Ahmed, Rafat Sultana; Chandna, Sudhir; Abegaonkar, Mahesh Pandurang; Tripathi, Ashok Kumar

    2013-01-01

    Background: Non-ionizing radiofrequency radiation has been increasingly used in industry, commerce, medicine and especially in mobile phone technology and has become a matter of serious concern in present time. Objective: The present study was designed to investigate the possible deoxyribonucleic acid (DNA) damaging effects of low-level microwave radiation in brain of Fischer rats. Materials and Methods: Experiments were performed on male Fischer rats exposed to microwave radiation for 30 days at three different frequencies: 900, 1800 and 2450 MHz. Animals were divided into 4 groups: Group I (Sham exposed): Animals not exposed to microwave radiation but kept under same conditions as that of other groups, Group II: Animals exposed to microwave radiation at frequency 900 MHz at specific absorption rate (SAR) 5.953 × 10−4 W/kg, Group III: Animals exposed to 1800 MHz at SAR 5.835 × 10−4 W/kg and Group IV: Animals exposed to 2450 MHz at SAR 6.672 × 10−4 W/kg. At the end of the exposure period animals were sacrificed immediately and DNA damage in brain tissue was assessed using alkaline comet assay. Results: In the present study, we demonstrated DNA damaging effects of low level microwave radiation in brain. Conclusion: We concluded that low SAR microwave radiation exposure at these frequencies may induce DNA strand breaks in brain tissue. PMID:23833433

  14. Microwave induced plasma for solid fuels and waste processing: A review on affecting factors and performance criteria.

    Science.gov (United States)

    Ho, Guan Sem; Faizal, Hasan Mohd; Ani, Farid Nasir

    2017-11-01

    High temperature thermal plasma has a major drawback which consumes high energy. Therefore, non-thermal plasma which uses comparatively lower energy, for instance, microwave plasma is more attractive to be applied in gasification process. Microwave-induced plasma gasification also carries the advantages in terms of simplicity, compactness, lightweight, uniform heating and the ability to operate under atmospheric pressure that gains attention from researchers. The present paper synthesizes the current knowledge available for microwave plasma gasification on solid fuels and waste, specifically on affecting parameters and their performance. The review starts with a brief outline on microwave plasma setup in general, and followed by the effect of various operating parameters on resulting output. Operating parameters including fuel characteristics, fuel injection position, microwave power, addition of steam, oxygen/fuel ratio and plasma working gas flow rate are discussed along with several performance criteria such as resulting syngas composition, efficiency, carbon conversion, and hydrogen production rate. Based on the present review, fuel retention time is found to be the key parameter that influences the gasification performance. Therefore, emphasis on retention time is necessary in order to improve the performance of microwave plasma gasification of solid fuels and wastes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Cytogenetic Damages Induced by Chronic Exposure to Microwave Non-Ionizing Radiofrequency Fields

    Directory of Open Access Journals (Sweden)

    Boris Đinđić

    2013-12-01

    Full Text Available Non-ionizing radiation has a significant and positive impact on modern society through a number of uses. There is increasing public concern regarding the health risks of radio-frequency (RF radiation, particularly that produced by mobile phones. Concern regarding the potential risks of exposure to EMFs has led to many epidemiological investigations, but the effects of EMF exposure on human and other mammalian cells are still unclear. One of the most frequently asked questions about the effects of microwave radiation on biological systems is whether they produce genotoxic effects and could be there a possible link with oncogenic processes. It is most difficult to get accurate and reproducible results for the studies that tell us most about the effects of EMF on humans. Based on some “weak” evidence suggesting an association between exposure to radiofrequency fields (RF emitted from mobile phones and two types of brain cancer, glioma and acoustic neuroma, the International Agency for Research on Cancer has classified RF as ‘possibly carcinogenic to humans’ in group 2B. Literature results suggest that pulsed microwaves from working environment can be the cause of genetic and cell alterations. Taken together, the increased frequency of DNA damages, increased intensity of oxydative stress and production of reactive oxygen species as well as prolonged disruption in DNA repair mechanisms could be possible mechanisms for microwave induced cytogenetic damages even at low-level electromagnetic fields. Although there were contradictory results about harmful effects of electromagnetic fields we recommend that the mobile phone should be kept as far as possible from the body during conversations and also during usual daily activities to reduce the absorption of radiation by cells. In addition, the appropriate intake of antioxidant-rich food or drugs may be helpful for preventing the genotoxic effects that could be caused by mobile phone use.

  16. Microwave-induced developmental defects in the common mealworm (Tenebrio molitor). A decade of research. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, R.G.

    1981-12-09

    Microwave-induced developmental effects in insects have been studied at several laboratories during the past decade. Results of the initial experiments were interpreted to show a 'nonthermal' microwave effect, but as more studies were conducted by various investigators, a predominantly thermal effect appeared to be the best explanation. This report presents the results of a comprehensive series of insect irradiation experiments including a rigorous statistical analysis of the data. Statistical analysis shows no microwave-induced effects for exposure of up to 4 hours at dose rates of 63 watts/kilogram. Irradiation at higher intensities (102-126 W/kg) did produce statistically significant effects when applied over a 2-4 hour period.

  17. The important role of microwave receptors in bio-fuel production by microwave-induced pyrolysis of sewage sludge.

    Science.gov (United States)

    Zuo, Wei; Tian, Yu; Ren, Nanqi

    2011-06-01

    Microwave receptor plays an important role in the microwave pyrolysis of sewage sludge in view of its significant influence on the yield and property of bio-fuel products. The yield and the chemical compositions of bio-fuels (gases and oils) obtained from sewage sludge mixed with different receptors (graphite, residue char, active carbon or silicon carbide) were investigated in this study by Gas Chromatography (GC), Gas Chromatography-Mass Spectrometry (GC-MS), and Fourier Transform Infrared Spectroscopy (FTIR). The results showed that the use of silicon carbide gave rise to the highest final temperature of 1130°C, resulting in the highest yield of gas fraction (up to 63.2 wt.%). The low heating rate (200°C/min) which was attributed to the addition of residue char promoted condensation reactions and resulted in an increase in solid yield. The existence of active carbon could prolong the resistance time of volatiles in the hot zone owing to its porous structure, generating the maximum concentration of H(2)+CO (60%) in the pyrolysis gas. When graphite was used, the final low temperature favoured the cyclization of the alkenes, giving rise to a higher concentration of mononuclear aromatics in the pyrolysis oils. The model established in this study revealed that the quantity and quality of the products obtained from the microwave pyrolysis highly depended on the process conditions, which were influenced by the receptor significantly. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. The feasibility of using microwave-induced thermoacoustic tomography for detection and evaluation of renal calculi.

    Science.gov (United States)

    Cao, Caijun; Nie, Liming; Lou, Cunguang; Xing, Da

    2010-09-07

    Imaging of renal calculi is important for patients who suffered a urinary calculus prior to treatment. The available imaging techniques include plain x-ray, ultrasound scan, intravenous urogram, computed tomography, etc. However, the visualization of a uric acid calculus (radiolucent calculi) is difficult and often impossible by the above imaging methods. In this paper, a new detection method based on microwave-induced thermoacoustic tomography was developed to detect the renal calculi. Thermoacoustic images of calcium oxalate and uric acid calculus were compared with their x-ray images. The microwave absorption differences among the calcium oxalate calculus, uric acid calculus and normal kidney tissue could be evaluated by the amplitude of the thermoacoustic signals. The calculi hidden in the swine kidney were clearly imaged with excellent contrast and resolution in the three orthogonal thermoacoustic images. The results indicate that thermoacoustic imaging may be developed as a complementary method for detecting renal calculi, and its low cost and effective feature shows high potential for clinical applications.

  19. The feasibility of using microwave-induced thermoacoustic tomography for detection and evaluation of renal calculi

    International Nuclear Information System (INIS)

    Cao Caijun; Nie Liming; Lou Cunguang; Xing Da

    2010-01-01

    Imaging of renal calculi is important for patients who suffered a urinary calculus prior to treatment. The available imaging techniques include plain x-ray, ultrasound scan, intravenous urogram, computed tomography, etc. However, the visualization of a uric acid calculus (radiolucent calculi) is difficult and often impossible by the above imaging methods. In this paper, a new detection method based on microwave-induced thermoacoustic tomography was developed to detect the renal calculi. Thermoacoustic images of calcium oxalate and uric acid calculus were compared with their x-ray images. The microwave absorption differences among the calcium oxalate calculus, uric acid calculus and normal kidney tissue could be evaluated by the amplitude of the thermoacoustic signals. The calculi hidden in the swine kidney were clearly imaged with excellent contrast and resolution in the three orthogonal thermoacoustic images. The results indicate that thermoacoustic imaging may be developed as a complementary method for detecting renal calculi, and its low cost and effective feature shows high potential for clinical applications.

  20. Examining of athermal effects in microwave-induced glucose/glycine reaction and degradation of polysaccharide from Porphyra yezoensis.

    Science.gov (United States)

    Zhou, Cunshan; Yu, Xiaojie; Ma, Haile; Liu, Shulan; Qin, Xiaopei; Yagoub, Abu El-Gasim A; Owusu, John

    2013-08-14

    Many reports claim the existence of athermal effects in microwave-induced reactions, and this challenge the assumption that the thermal effect (heating) is the sole factor in microwave heating. Therefore, microwave-induced Maillard reaction of d-glucose/glycine and degradation of polysaccharide from Porphyra yezoensis (PSPY) were investigated. Browning reactions were monitored by measuring heating rate, UV-absorbance and brown color, UV-vis and synchronous fluorescence spectra, GC/MS analysis and intrinsic viscosity of degradation. Heating of d-glucose/glycine solution produced brown compounds which were detected at A420, and the intermediate products, 2-acetylfuran and 5-methylfurfural, whose fluorescence intensity evidenced their formation. Maximum emission of synchronous fluorescence spectra of samples were at 430-440 nm and 370-390 nm. Both microwave and water bath heating did not cause any compositional changes in the Maillard reaction products. All data failed to show any significant athermal effects of compositional changes in the Maillard reaction products. It can be inferred that some of the reports suggesting the existence of athermal effects, which could ascribe to the different set-up obtained in not well temperature controlled microwave heating systems. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. MICROWAVE INDUCED DEGRADATION OF GLASS FIBER REINFORCED POLYESTER FOR FIBER AND RESIN RECOVERY

    DEFF Research Database (Denmark)

    Ucar, Hülya; Nielsen, Rudi Pankratz; Søgaard, Erik Gydesen

    A solvolysis process to depolymerize the resin in glass fiber reinforced composites and recover the glass fibers has been investigated using microwave induced irradiation. The depolymerization was carried out in HNO3 with concentrations in the range of 1M-7M and in KOH with concentrations ranging...... of depolymerization was achieved using KOH at concentrations ranging from 1-3.5M. Maximum 63 % resin removal was achieved using 1 M KOH and the resin removal efficiency decreased at higher KOH concentrations (3.5M). The glass fiber surfaces were damaged at both concentrations with more pronounced damages using 3.5M...... KOH. It was not possible to recover monomers using KOH....

  2. The Compound Chinese Medicine “Kang Fu Ling” Protects against High Power Microwave-Induced Myocardial Injury

    Science.gov (United States)

    Zhang, Xueyan; Gao, Yabing; Dong, Ji; Wang, Shuiming; Yao, Binwei; Zhang, Jing; Hu, Shaohua; Xu, Xinping; Zuo, Hongyan; Wang, Lifeng; Zhou, Hongmei; Zhao, Li; Peng, Ruiyun

    2014-01-01

    Background The prevention and treatment of Microwave-caused cardiovascular injury remains elusive. This study investigated the cardiovascular protective effects of compound Chinese medicine “Kang Fu Ling” (KFL) against high power microwave (HPM)-induced myocardial injury and the role of the mitochondrial permeability transition pore (mPTP) opening in KFL protection. Methods Male Wistar rats (100) were divided into 5 equal groups: no treatment, radiation only, or radiation followed by treatment with KFL at 0.75, 1.5, or 3 g/kg/day. Electrocardiography was used to Electrophysiological examination. Histological and ultrastructural changes in heart tissue and isolated mitochondria were observed by light microscope and electron microscopy. mPTP opening and mitochondrial membrane potential were detected by confocal laser scanning microscopy and fluorescence analysis. Connexin-43 (Cx-43) and endothelial nitric oxide synthase (eNOS) were detected by immunohistochemistry. The expression of voltage-dependent anion channel (VDAC) was detected by western blotting. Results At 7 days after radiation, rats without KFL treatment showed a significantly lower heart rate (Pmicrowave-induced decrease of Cx-43 and VDAC protein expression was significantly reversed. Conclusion Microwave radiation can cause electrophysiological, histological and ultrastructural changes in the heart. KFL at 1.5 g/kg/day had the greatest protective effect on these cardiovascular events. mPTP plays an important role in the protective effects of KFL against microwave-radiation-induced myocardial injury. PMID:24992449

  3. Observation of injury effects and apoptosis induced by microwave and gamma ray on lymphocyte in Raji cell

    International Nuclear Information System (INIS)

    Xia Hongjie; Wang Dewen; Zuo Hongyan; Xu Xinping; Jia Kai; Qiu Bingtao

    2011-01-01

    To investigate the rule of apoptosis, necrosis and the effects of Raji cell induced by microwave and gamma ray, the Raji cell was exposed to microwave radiation and gamma radiation. Morphological changes were observed by inverted phase contrast microscope before and after radiation. Annexin-V and PI double labelling were used to detect changes of apoptosis and necrosis rate. The results show that the cell shape was changed and the rate of apoptosis and necrosis were increased after exposure to microwave and γ ray. The injury effect of γ+S-HPM compound radiation was more serious than any single radiation on lymphocyte. The major characteristics of injury showed as gamma ray effect. The trends of apoptosis and necrosis keep consistency with the change of the cell morphology after radiation between each observation group. (authors)

  4. Surface-nitriding treatment of steels using microwave-induced nitrogen plasma at atmospheric pressure

    International Nuclear Information System (INIS)

    Sato, Shigeo; Arai, Yuuki; Yamashita, Noboru; Kojyo, Atsushi; Kodama, Kenji; Ohtsu, Naofumi; Okamoto, Yukio; Wagatsuma, Kazuaki

    2012-01-01

    A rapid surface-nitriding system using microwave-induced nitrogen plasma at atmospheric pressure was developed for modifying iron and steel surfaces. Since the conventional plasma nitriding technique requires a low-pressure atmosphere in the treatment chamber, the population of excited nitrogen molecules in the plasma is limited. Accordingly, several hours are required for nitriding treatment. By contrast, the developed nitriding system can use atmospheric-pressure plasma through application of the Okamoto cavity for excitation of nitrogen plasma. The high population of excited nitrogen molecules induced by the atmospheric-pressure plasma allowed the formation of a nitriding layer that was several micrometers thick within 1 min and produced an expanded austenite iron phase with a high nitrogen concentration close to the solubility limit on the iron substrate. In addition, the nitriding treatment on high-chromium steel was performed by introducing a reducing gas such as NH 3 and H 2 into the treatment chamber. While the nitriding reaction did not proceed in a simple N 2 atmosphere due to surface oxidation, the surface reduction induced by the NH 3 or H 2 gas promoted the nitriding reaction at the surface. These nitriding phenomena characteristics of the atmospheric-pressure plasma are discussed in this paper based on the effects of the specimen temperature and plasma atmosphere on the thickness, the chemical states, and the nitride compounds of the nitrided layer as investigated by X-ray diffraction, glow-discharge optical emission spectroscopy, and X-ray photoelectron spectroscopy.

  5. 1800MHz Microwave Induces p53 and p53-Mediated Caspase-3 Activation Leading to Cell Apoptosis In Vitro.

    Directory of Open Access Journals (Sweden)

    Fuqiang Xing

    Full Text Available Recent studies have reported that exposure of mammalian cells to microwave radiation may have adverse effects such as induction of cell apoptosis. However, the molecular mechanisms underlying microwave induced mammalian cell apoptosis are not fully understood. Here, we report a novel mechanism: exposure to 1800MHz microwave radiation induces p53-dependent cell apoptosis through cytochrome c-mediated caspase-3 activation pathway. We first measured intensity of microwave radiation from several electronic devices with an irradiation detector. Mouse NIH/3T3 and human U-87 MG cells were then used as receivers of 1800MHz electromagnetic radiation (EMR at a power density of 1209 mW/m2. Following EMR exposure, cells were analyzed for viability, intracellular reactive oxygen species (ROS generation, DNA damage, p53 expression, and caspase-3 activity. Our analysis revealed that EMR exposure significantly decreased viability of NIH/3T3 and U-87 MG cells, and increased caspase-3 activity. ROS burst was observed at 6 h and 48 h in NIH/3T3 cells, while at 3 h in U-87 MG cells. Hoechst 33258 staining and in situ TUNEL assay detected that EMR exposure increased DNA damage, which was significantly restrained in the presence of N-acetyl-L-cysteine (NAC, an antioxidant. Moreover, EMR exposure increased the levels of p53 protein and p53 target gene expression, promoted cytochrome c release from mitochondrion, and increased caspase-3 activity. These events were inhibited by pretreatment with NAC, pifithrin-α (a p53 inhibitor and caspase inhibitor. Collectively, our findings demonstrate, for the first time, that 1800MHz EMR induces apoptosis-related events such as ROS burst and more oxidative DNA damage, which in turn promote p53-dependent caspase-3 activation through release of cytochrome c from mitochondrion. These findings thus provide new insights into physiological mechanisms underlying microwave-induced cell apoptosis.

  6. 1800MHz Microwave Induces p53 and p53-Mediated Caspase-3 Activation Leading to Cell Apoptosis In Vitro

    Science.gov (United States)

    Xing, Fuqiang; Zhan, Qiuqiang; He, Yiduo; Cui, Jiesheng; He, Sailing; Wang, Guanyu

    2016-01-01

    Recent studies have reported that exposure of mammalian cells to microwave radiation may have adverse effects such as induction of cell apoptosis. However, the molecular mechanisms underlying microwave induced mammalian cell apoptosis are not fully understood. Here, we report a novel mechanism: exposure to 1800MHz microwave radiation induces p53-dependent cell apoptosis through cytochrome c-mediated caspase-3 activation pathway. We first measured intensity of microwave radiation from several electronic devices with an irradiation detector. Mouse NIH/3T3 and human U-87 MG cells were then used as receivers of 1800MHz electromagnetic radiation (EMR) at a power density of 1209 mW/m2. Following EMR exposure, cells were analyzed for viability, intracellular reactive oxygen species (ROS) generation, DNA damage, p53 expression, and caspase-3 activity. Our analysis revealed that EMR exposure significantly decreased viability of NIH/3T3 and U-87 MG cells, and increased caspase-3 activity. ROS burst was observed at 6 h and 48 h in NIH/3T3 cells, while at 3 h in U-87 MG cells. Hoechst 33258 staining and in situ TUNEL assay detected that EMR exposure increased DNA damage, which was significantly restrained in the presence of N-acetyl-L-cysteine (NAC, an antioxidant). Moreover, EMR exposure increased the levels of p53 protein and p53 target gene expression, promoted cytochrome c release from mitochondrion, and increased caspase-3 activity. These events were inhibited by pretreatment with NAC, pifithrin-α (a p53 inhibitor) and caspase inhibitor. Collectively, our findings demonstrate, for the first time, that 1800MHz EMR induces apoptosis-related events such as ROS burst and more oxidative DNA damage, which in turn promote p53-dependent caspase-3 activation through release of cytochrome c from mitochondrion. These findings thus provide new insights into physiological mechanisms underlying microwave-induced cell apoptosis. PMID:27689798

  7. Microwave Heating: A Time Saving Technology or a Way to Induce Vegetable Oils Oxidation?

    OpenAIRE

    Malheiro, Ricardo; Casal, Susana; Ramalhosa, Elsa; Pereira, José Alberto

    2011-01-01

    Microwave heating features modern lifestyle. The use of this technology enables a significant reduction in the time dedicated to prepare meals and opens new perspectives at the industrial level. In this chapter we report the combined effect of time/applied potency of microwave heating in comparison to conventional electric oven on the quality of vegetable oils. In general, the degradation pattern of vegetable oils under microwave heating was similar to that expected from other...

  8. Non-Destructive Evaluation of Materials Using Pulsed Microwave Interrogating Signals and Acoustic Wave Induced Reflections

    National Research Council Canada - National Science Library

    Albanese, R

    2002-01-01

    A class of inverse problems is formulated for the estimation of material dielectric parameters using reflections of pulsed microwave interrogating signals from moving acoustic interfaces in the dielectric...

  9. Renewable hydrocarbons for jet fuels from biomass and plastics via microwave-induced pyrolysis and hydrogenation processes

    Science.gov (United States)

    Zhang, Xuesong

    This dissertation aims to enhance the production of aromatic hydrocarbons in the catalytic microwave-induced pyrolysis, and maximize the production of renewable cycloalkanes for jet fuels in the hydrogenation process. In the process, ZSM-5 catalyst as the highly efficient catalyst was employed for catalyzing the pyrolytic volatiles from thermal decomposition of cellulose (a model compound of lignocellulosic biomass). A central composite experiment design (CCD) was used to optimize the product yields as a function of independent factors (e.g. catalytic temperature and catalyst to feed mass ratio). The low-density polyethylene (a mode compound of waste plastics) was then carried out in the catalytic microwave-induced pyrolysis in the presence of ZSM-5 catalyst. Thereafter, the catalytic microwave-induced co-pyrolysis of cellulose with low-density polyethylene (LDPE) was conducted over ZSM-5 catalyst. The results showed that the production of aromatic hydrocarbons was significantly enhanced and the coke formation was also considerably reduced comparing with the catalytic microwave pyrolysis of cellulose or LDPE alone. Moreover, practical lignocellulosic biomass (Douglas fir sawdust pellets) was converted into aromatics-enriched bio-oil by catalytic microwave pyrolysis. The bio-oil was subsequently hydrogenated by using the Raney Ni catalyst. A liquid-liquid extraction step was implemented to recover the liquid organics and remove the water content. Over 20% carbon yield of liquid product regarding lignocellulosic biomass was obtained. Up to 90% selectivity in the liquid product belongs to jet fuel range cycloalkanes. As the integrated processes was developed, catalytic microwave pyrolysis of cellulose with LDPE was conducted to improve aromatic production. After the liquid-liquid extraction by the optimal solvent (n-heptane), over 40% carbon yield of hydrogenated organics based on cellulose and LDPE were achieved in the hydrogenation process. As such, real

  10. Is Limb Salvage With Microwave-induced Hyperthermia Better Than Amputation for Osteosarcoma of the Distal Tibia?

    Science.gov (United States)

    Han, Kang; Dang, Peiye; Bian, Na; Chen, Xiang; Yang, Tongtao; Fan, QingYu; Zhou, Yong; Zhao, Tingbao; Wang, Pingshan

    2017-06-01

    Amputation has been the standard surgical treatment for distal tibia osteosarcoma owing to its unique anatomic features. Preliminary research suggested that microwave-induced hyperthermia may have a role in treating osteosarcoma in some locations of the body (such as the pelvis), but to our knowledge, no comparative study has evaluated its efficacy in a difficult-to-treat location like the distal tibia. Does microwave-induced hyperthermia result in (1) improved survival, (2) decreased local recurrence, (3) improved Musculoskeletal Tumor Society (MSTS) scores, or (4) fewer complications than amputation in patients with a distal tibial osteosarcoma? Between 2000 and 2015, we treated 79 patients for a distal tibia osteosarcoma without metastases. Of those, 52 were treated with microwave-induced hyperthermia, and 27 with amputation. Patients were considered eligible for microwave-induced hyperthermia if they had an at least 20-mm available distance from the tumor edge to the articular surface, good clinical and imaging response to neoadjuvant chemotherapy, and no pathologic fracture. Patients not meeting these indications were treated with amputation. In addition, if neither the posterior tibial artery nor the dorsalis pedis artery was salvageable, the patients were treated with amputation and were not included in any group in this study. A total of 13 other patients were treated with conventional limb-salvage resections and reconstructions (at the request of the patient, based on patient preference) and were not included in this study. All 79 patients in this retrospective study were available for followup at a minimum of 12 months (mean followup in the hyperthermia group, 79 months, range 12-158 months; mean followup in the amputation group, 95 months, range, 15-142 months). With the numbers available, the groups were no different in terms of sex, age, tumor grade, tumor stage, or tumor size. All statistical tests were two-sided, and a probability less than 0.05 was

  11. Microwave-induced porosity and bioactivation of chitosan-PEGDA scaffolds: morphology, mechanical properties and osteogenic differentiation.

    Science.gov (United States)

    Demitri, Christian; Giuri, Antonella; De Benedictis, Vincenzo Maria; Raucci, Maria Grazia; Giugliano, Daniela; Sannino, Alessandro; Ambrosio, Luigi

    2017-01-01

    In this study, a new foaming method, based on physical foaming combined with microwave-induced curing, is proposed in combination with a surface bioactivation to develop scaffold for bone tissue regeneration. In the first step of the process, a stable physical foaming was induced using a surfactant (Pluronic) as blowing agent of a homogeneous blend of Chitosan and polyethylene glycol diacrylate (PEGDA700) solutions. In the second step, the porous structure of the foaming was chemically stabilized by radical polymerization induced by homogeneous heating of the sample in a microwave reactor. In this step, 2,2-azobis[2-(2-imidazolin-2yl)propane]dihydrochloride was used as thermoinitiator (TI). Chitosan and PEGDA were mixed in different blends to investigate the influence of the composition on the final properties of the material. The chemical properties of each sample were evaluated by infrared attenuated total reflectance analysis, before and after curing in order to maximize reaction yield and optimize kinetic parameters (i.e. time curing, microwave power). Absorption capacity, elastic modulus, porosity and morphology of the porous structure were measured for each sample. The stability of materials was evaluated in vitro by degradation test in phosphate-buffered saline. To improve the bioactivity and biological properties of chitosan scaffold, a biomineralization process was used. Biological characterization was carried out with the aim to prove the effect of biomineralization scaffold on human mesenchymal stem cells behaviour. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Microwave-induced carbon nanotubes catalytic degradation of organic pollutants in aqueous solution.

    Science.gov (United States)

    Chen, Jing; Xue, Shuang; Song, Youtao; Shen, Manli; Zhang, Zhaohong; Yuan, Tianxin; Tian, Fangyuan; Dionysiou, Dionysios D

    2016-06-05

    In this study, a new catalytic degradation technology using microwave induced carbon nanotubes (MW/CNTs) was proposed and applied in the treatment of organic pollutants in aqueous solution. The catalytic activity of three CNTs of 10-20nm, 20-40nm, and 40-60nm diameters were compared. The results showed that organic pollutants such as methyl orange (MO), methyl parathion (MP), sodium dodecyl benzene sulfonate (SDBS), bisphenol A (BPA), and methylene blue (MB) in aqueous solution could be degraded effectively and rapidly in MW/CNTs system. CNTs with diameter of 10-20nm exhibited the highest catalytic activity of the three CNTs under MW irradiation. Further, complete degradation was obtained using 10-20nm CNTs within 7.0min irradiation when 25mL MO solution (25mg/L), 1.2g/L catalyst dose, 450W, 2450MHz, and pH=6.0 were applied. The rate constants (k) for the degradation of SDBS, MB, MP, MO and BPA using 10-20nm CNTs/MW system were 0.726, 0.679, 0.463, 0.334 and 0.168min(-1), respectively. Therefore, this technology may have potential application for the treatment of targeted organic pollutants in wastewaters. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. A Novel Microwave-Induced Plasma Ionization Source for Ion Mobility Spectrometry

    Science.gov (United States)

    Dai, Jianxiong; Zhao, Zhongjun; Liang, Gaoling; Duan, Yixiang

    2017-03-01

    This work demonstrates the application of a novel microwave induced plasma ionization (MIPI) source to ion mobility spectrometry (IMS). The MIPI source, called Surfatron, is composed of a copper cavity and a hollow quartz discharge tube. The ion mobility spectrum of synthetics air has a main peak with reduced mobility of 2.14 cm2V-1s-1 for positive ion mode and 2.29 cm2V-1s-1 for negative ion mode. The relative standard deviations (RSD) are 0.7% and 1.2% for positive and negative ion mode, respectively. The total ion current measured was more than 3.5 nA, which is much higher than that of the conventional 63Ni source. This indicates that a better signal-to-noise ratio (SNR) can be acquired from the MIPI source. The SNR was 110 in the analysis of 500 pptv methyl tert-butyl ether (MTBE), resulting in the limit of detection (SNR = 3) of 14 pptv. The linear range covers close to 2.5 orders of magnitude in the detection of triethylamine with a concentration range from 500 pptv to 80 ppbv. Finally, this new MIPI-IMS was used to detect some volatile organic compounds, which demonstrated that the MIPI-IMS has great potential in monitoring pollutants in air.

  14. Radiofrequency (microwave) radiation exposure of mammalian cells during UV-induced DNA repair synthesis

    International Nuclear Information System (INIS)

    Meltz, M.L.; Walker, K.A.; Erwin, D.N.

    1987-01-01

    The effect of continuous-wave (CW) and pulsed-wave (PW) radiofrequency radiation (RFR) in the microwave range on UV-induced DNA repair has been investigated in MRC-5 normal human diploid fibroblasts. RFR exposure at power densities of 1 (or 5) and 10 mW/cm2 gave a maximum specific absorption rate (SAR) (at 10 mW/cm2) of 0.39 +/- 0.15 W/kg for 350 MHz RFR, 4.5 +/- 3.0 W/kg for 850 MHz RFR, and 2.7 +/- 1.6 W/kg for 1.2 GHz RFR. RFR exposures for 1 to 3 h at 37 degrees C, in either continuous-wave or pulsed-wave modes, had no effect on the rate of repair replication label incorporated into preexisting UV-damaged DNA. RFR exposures (PW), with a constant medium temperature of 39 degrees C at 350 and 850 MHz during the repair period after UV damage, also had no effect. Assay for induction of repair synthesis by RFR exposure alone in non-UV irradiated cells was negative for the 350-, 850-, and 1200-MHz CW and PW RFR at 37 degrees C and the 350- and 850-MHz PW RFR at 39 degrees C. RFR does not induce DNA repair under these exposure conditions. In preliminary experiments--with the tissue culture medium maintained at 39 degrees C and RFR exposures (PW) at the frequencies of 350, 850, and 1200 MHz--no effect on incorporation of [ 3 H]thymidine into DNA undergoing semiconservative synthesis was observed

  15. Radiofrequency (microwave) radiation exposure of mammalian cells during UV-induced DNA repair synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Meltz, M.L.; Walker, K.A.; Erwin, D.N.

    1987-05-01

    The effect of continuous-wave (CW) and pulsed-wave (PW) radiofrequency radiation (RFR) in the microwave range on UV-induced DNA repair has been investigated in MRC-5 normal human diploid fibroblasts. RFR exposure at power densities of 1 (or 5) and 10 mW/cm2 gave a maximum specific absorption rate (SAR) (at 10 mW/cm2) of 0.39 +/- 0.15 W/kg for 350 MHz RFR, 4.5 +/- 3.0 W/kg for 850 MHz RFR, and 2.7 +/- 1.6 W/kg for 1.2 GHz RFR. RFR exposures for 1 to 3 h at 37 degrees C, in either continuous-wave or pulsed-wave modes, had no effect on the rate of repair replication label incorporated into preexisting UV-damaged DNA. RFR exposures (PW), with a constant medium temperature of 39 degrees C at 350 and 850 MHz during the repair period after UV damage, also had no effect. Assay for induction of repair synthesis by RFR exposure alone in non-UV irradiated cells was negative for the 350-, 850-, and 1200-MHz CW and PW RFR at 37 degrees C and the 350- and 850-MHz PW RFR at 39 degrees C. RFR does not induce DNA repair under these exposure conditions. In preliminary experiments--with the tissue culture medium maintained at 39 degrees C and RFR exposures (PW) at the frequencies of 350, 850, and 1200 MHz--no effect on incorporation of (/sup 3/H)thymidine into DNA undergoing semiconservative synthesis was observed.

  16. Microwave-induced direct spin-flip transitions in mesoscopic Pd/Co heterojunctions

    Science.gov (United States)

    Pietsch, Torsten; Egle, Stefan; Keller, Martin; Fridtjof-Pernau, Hans; Strigl, Florian; Scheer, Elke

    2016-09-01

    We experimentally investigate the effect of resonant microwave absorption on the magneto-conductance of tunable Co/Pd point contacts. At the interface a non-equilibrium spin accumulation is created via microwave absorption and can be probed via point contact spectroscopy. We interpret the results as a signature of direct spin-flip excitations in Zeeman-split spin-subbands within the Pd normal metal part of the junction. The inverse effect, which is associated with the emission of a microwave photon in a ferromagnet/normal metal point contact, can also be detected via its unique signature in transport spectroscopy.

  17. Study on microwave induced pyrolysis of low metamorphic coal and liquefaction residue

    Science.gov (United States)

    Li, Zhao; Wu, Kunyao; Cao, Jing; Wang, Yongfeng

    2017-05-01

    This paper mainly studies pyrolysis characteristic in the different heating of microwave of low metamorphic coal and Liquefaction Residue, which was focused on the effects of particle sizes, pyrolysis reaction time, and microwave powers. The product are analyzed by Gas chromatography- mass spectrometry (GC-MS), etc. The results showed that when heating time is 40 min and 800 W, yield of tar is about 15.51%.

  18. Microwave-induced changes in the decay rates of positronium localised in fluid ethane

    International Nuclear Information System (INIS)

    Sharma, S.C.; Arganbright, R.H.; Ward, M.H.

    1987-01-01

    We have measured pick-off annihilation rates of orthopositronium localised in density fluctuations in fluid ethane as a function of microwave frequency in the range 90-100 GHz. Significant reductions in the annihilation rates are observed at 92 and 96.2 GHz. Possible mechanisms for microwave absorption and for the resulting decrease in the local density of electrons around Ps are discussed. (author)

  19. Microwave-induced crystallization of AC/TiO{sub 2} for improving the performance of rhodamine B dye degradation

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Fei [School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003 (China); Wu, Zhansheng, E-mail: wuzhans@126.com [School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003 (China); Chen, Qiuyu; Yan, Yujun [School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003 (China); Cravotto, Giancarlo; Wu, Zhilin [Dipartimento di Scienza e Tecnologia del Farmaco, University of Turin, Torino 10125 (Italy)

    2015-10-01

    Graphical abstract: - Highlights: • Mixed phase titania coated with AC was obtained by microwave irradiation method. • The TiO{sub 2} nanoparticles were spherical and well distributed on the surface of AC. • The light absorption edges of AC/TiO{sub 2} showed red-shift compared to the pure TiO{sub 2}. • Higher surface and TiO{sub 2} content of AC/TiO{sub 2} could improve photocatalytic efficiency. - Abstract: Titanium dioxide (TiO{sub 2}) deposition on activated carbon (AC) is widely used for pollutant photodegradation. In this study, a simple and efficient method for preparing AC/TiO{sub 2} composites under microwave irradiation was developed for photocatalytic degradation of rhodamine B (RhB) under UV light. Results of X-ray diffraction, scanning electron microscopy, and transmission electron microscopy revealed that TiO{sub 2} nanoparticles are anatase and rutile, with a spherical shape and a particle size of 20–50 nm and are well distributed on the AC surface. The UV–vis spectrum of TiO{sub 2} coated on AC showed an evident red-shift and exhibited stronger optical absorption capacity than pure TiO{sub 2}. The AC/TiO{sub 2} nanoparticles prepared at a microwave power of 700 W for 15 min exhibited 98% efficiency in removing RhB dye under UV irradiation for 30 min. The high photocatalytic activity of AC/TiO{sub 2}-700 W could be mainly attributed to the high sorption capacity of the mesoporous carbon material and high TiO{sub 2} content, which could produce higher quantity of ·OH. This study provides a rapid synthesis technique to prepare AC/TiO{sub 2} and a novel method to improve photocatalytic efficiency via synergistic effect for other catalytic systems.

  20. Microwave-induced combustion synthesis of aluminum oxide-titanium carbide powder

    Science.gov (United States)

    Atong, Duangduen

    2000-11-01

    Microwave heating offers many potential advantages, including synthesizing of material. This advantage results from the unique features of microwave heating which include its internal volumetric heating and subsequent inverted temperature profile. Fundamental knowledge of how reaction parameters influence microwave-ignition behavior is needed in order to provide information required for synthesizing the desired products. This study was performed to synthesize Al2O3-TiC powders by using microwave heating. The important reaction parameters were identified using the Plackett-Burman design including amount of excess Al and Al2O3, particle size of C and Al2O 3, and heating method. The effect of these reaction parameters on the ignition behavior and characteristics of the resulting powders was then evaluated by the central composite design. The combustion synthesis of Al2O3-TiC powders using microwave heating (MH) and microwave hybrid heating (MHH) was successfully achieved. The MHH-ignited sample required a longer time to reach ignition temperature and thus resulted in a lower combustion temperature. The results showed no significant difference in characteristics of powders ignition time and temperature, while decreasing the combustion temperature. An increased particle size of Al2O3 lowered the ignition time and temperature. The density of product decreased with increasing amounts of Al. Addition of excess Al2O3 to reactants resulted in decreasing the agglomeration size. The empirical models relating these important parameters and their interactions to the responses were then developed. The mechanism governing the combustion reaction of Al2O 3-TiC powders under microwave and conventional heating was also investigated. The results suggested that reaction mechanisms using these two methods were similar. The reaction proceeded in a three-stage process where the aluminum melted, then the melting Al reacted with the titania, and finally the titanium reacted with the carbon

  1. Arabidopsis Vacuolar Pyrophosphatase gene (AVP1) induces drought and salt tolerance in Nicotiana tabacum plants (abstract)

    International Nuclear Information System (INIS)

    Arif, A.; Mohsin, A.M.; Shafiq, S.; Zafar, Y.; Hameed, S.M.; Arif, M.; Javed, M.; Gaxiola, R.A.

    2005-01-01

    /sup +/ ions from the soil to the vacoules by providing energy gradient to the cation exchangers. It was also found that K/sup +/ concentration decreased below detection limit in salt treated transgenic plants. Sodium and potassium ion uptake in the dehydrated AVP1 transgenic plant was two times more when compared to the dehydrated wild type plants. Relative water contents of dehydrated AVP1 transgenic plants was higher than that of dehydrated wild type which indicates that accumulation of solutes retain more water in the cell which helps to maintain the turgor and allows the plants to survive in saline and water deficit environments. Electron microscopic ultra structure studies of leaves showed that there is an increase of starch synthesis in the chloroplasts of AVP1 transgenic plants when compared to control. Immunogold labeling of AVP1 protein in transgenic and control leaf cells and some other physiological studies are in progress. AVP1 gene is encoded by a single gene so it is more feasible to produce transgenic crop plants with AVP1 to induce salt and drought tolerance unlike P type ATPAases which are encoded by at least 26 genes. (author)

  2. The influence of microwave irradiation on thermal properties of main rock-forming minerals

    International Nuclear Information System (INIS)

    Lu, Gao-ming; Li, Yuan-hui; Hassani, Ferri; Zhang, Xiwei

    2017-01-01

    Highlights: • Different rock-forming minerals present very different microwave absorption capacity to microwave energy. • The test results can be used to estimate the heating behaviors of rocks to microwave irradiation. • SEM-EDX technique was used to determine the elemental distribution and mineralogical composition. • Ferrum may influence the interacting mechanisms between rock-forming minerals and microwaves. - Abstract: The sample will burst into fragment when the thermal stress induced by thermal expansion greater than the ultimate strength of the rock after microwave irradiation. Microwave-assisted rock fragmentation has been illustrated to be potentially beneficial for mineral processing, mining and geotechnical engineering. In order to have a comprehensive understanding on the influence of microwave on thermo-mechanical properties of rocks, it is necessary to investigate the interaction effect between microwaves and the main rock-forming minerals. In this work, eleven rock-forming minerals were tested in a multimode cavity at 2.45G Hz with a power of 2 kW, subsequently, the Scanning Electron Microscopy–Energy Dispersive X-ray (SEM-EDX) was used to determine the elemental distribution and mineralogical composition of the tested samples. It was observed that different rock-forming minerals present very different susceptibility induced by microwave treatment. Enstatite presents the strongest microwave absorption capacity by a large margin and most of the rock-forming minerals are weak microwave absorbers. It is significant that the results can be used to predict the heating behaviors of rocks subjected to microwave energy. Furthermore, the SEM-EDX elemental analysis demonstrates that the microwave absorption capacity of rock-forming minerals could link to the contribution of the ferrum, which may influence the interacting mechanisms between microwaves and the rock-forming minerals.

  3. Field induced decrystallization of silicon: Evidence of a microwave non-thermal effect

    Science.gov (United States)

    Nozariasbmarz, Amin; Dsouza, Kelvin; Vashaee, Daryoosh

    2018-02-01

    It is rather strange and not fully understood that some materials decrystallize when exposed to microwave radiation, and it is still debatable if such a transformation is a thermal or non-thermal effect. We hereby report experimental evidences that weight the latter effect. First, a single crystal silicon wafer exposed to microwaves showed strong decrystallization at high temperature. Second, when some areas of the wafer were masked with metal coating, only the exposed areas underwent decrystallization. Transmission electron microscopy analysis, x-ray diffraction data, and thermal conductivity measurements all indicated strong decrystallization, which occurred in the bulk of the material and was not a surface effect. These observations favor the existence of a non-thermal microwave effect.

  4. Sheath and bulk expansion induced by RF bias in atmospheric pressure microwave plasma

    Science.gov (United States)

    Lee, Jimo; Nam, Woojin; Lee, Jae Koo; Yun, Gunsu

    2017-10-01

    A large axial volume expansion of microwave-driven plasma at atmospheric pressure is achieved by applying a low power radio frequency (RF) bias at an axial location well isolated from the original plasma bulk. The evolution of the plasma plume visualized by high speed ICCD imaging suggest that the free electrons drifting toward the bias electrode cause the prodigious expansion of the sheath, creating a stable plasma stream channel between the microwave and the RF electrodes. For argon plasma in ambient air, enhanced emissions of OH and N2 spectral lines are measured in the extended plume region, supporting the acceleration of electrons and subsequent generation of radical species. The coupling of RF bias with microwave provides an efficient way of enlarging the plasma volume and enhancing the production of radicals. Work supported by the National Research Foundation of Korea under BK21+ program and Grant No. 2015R1D1A1A01061556 (Ministry of Education).

  5. Nickel, sulfur and vanadium determination in residues from crude oil distillation by ICPOES after microwave-induced combustion

    International Nuclear Information System (INIS)

    Mello, P.A.; Pereira, J.S.F.; Dressler, V.L.; Flores, E.M.M.

    2009-01-01

    Full text: A microwave-induced combustion method is proposed for digestion of atmospheric and vacuum residues from heavy crude oil for simultaneous Ni, S and V determination by ICPOES. Ammonium nitrate solution (6 M, 50 μl) was used as igniter. Operational parameters were investigated as maximum sample mass, initial O 2 pressure, type and concentration of absorbing solutions (H 2 O, H 2 O 2 , and HNO 3 ) and the necessity of additional reflux steps. Accuracy was better than 98 %. Limits of detection were 0.2, 2 and 0.1 mg kg -1 for Ni, S and V, respectively. (author)

  6. Stability of Continental Lithosphere based on Analogue Experiments with Microwave Induced Internal Heating

    Science.gov (United States)

    Fourel, Loic; Limare, Angela; Surducan, Emanoil; Surducan, Vasile; Neamtu, Camelia; Vilella, Kenny; Farnetani, Cinzia; Kaminski, Edouard; Jaupart, Claude

    2015-04-01

    Continental lithosphere is usually depicted as the upper conductive layer of the Earth. Its formation is achieved through melt depletion that generates a residue that is less dense and more viscous than the underlying convecting mantle. As it is cooled from above, continental lithosphere can develop its own convective currents and may become unstable depending on its thickness and density contrast with the mantle. But chemical differentiation due to mantle magmatism also enriches continental lithosphere in heat producing elements. According to present estimates, the Earth's mantle may have lost as much as half of its radioactive elements in favour of continental crust and this stratified redistribution of heat sources has two main effects. First, mantle convection vigor decreases and becomes increasingly sensitive to heat supply from the core. Second, localized heat production at the top surface increases the continental insulating effects and competes against lithospheric instabilities. In the present study, we focus on the later and we determine which amount of internal heating is required to keep the lithosphere stable for a given rate of cooling from the top. The physics underlying instability triggering corresponds to the problem of a two differentially heated layered system cooled from above, where the top layer is less dense and more viscous than the bottom one, representative of the lithosphere-mantle system. Few studies have been devoted to the intrinsic characteristics of this layered type of convection. Here, we present a state of the art laboratory setup to generate internal heating in controlled conditions based on microwave (MW) absorption. The volumetric heat source can be localized in space and its intensity can be varied in time. Our tank prototype has horizontal dimensions of 30 cm x 30 cm and 5 cm height. A uniform and constant temperature is maintained at the upper boundary by an aluminium heat exchanger and adiabatic conditions are imposed at

  7. Effect of Aqueous Extract from Morinda officinalis F. C. How on Microwave-Induced Hypothalamic-Pituitary-Testis Axis Impairment in Male Sprague-Dawley Rats

    Directory of Open Access Journals (Sweden)

    Bin Song

    2015-01-01

    Full Text Available The present study aimed to assess the protective effects of aqueous extract from Morinda officinalis F. C. How on microwave-induced reproductive impairment in male rats. Microwave exposure injury was induced by exposure of 900 MHz microwaves at 218 μm/cm2 radiation densities, 24 hours/day for 10 days. Male Sprague-Dawley rats were randomized to: normal control, microwave exposure model, or water layer or ethyl acetate layer of aqueous extract 40 g/kg treatment groups. After 2 weeks of treatment, sexual performance, serum levels of gonadotrophin-releasing hormone (GnRH, luteinizing hormone (LH, follicle-stimulating hormone (FSH or testosterone, morphological analysis of testis and epididymis, and GnRH protein expression in the hypothalamus were measured. Pretreatment with water layer of aqueous extract 40 g/kg significantly improved sexual performance, increased serum testosterone level, and decreased LH and GnRH level compared with microwave exposed model rats (all P<0.05. Water layer of aqueous extract treatment significantly increased seminiferous cell or sperm number in testis and epididymis. Protein expression of GnRH in the hypothalamus significantly decreased in the water layer of aqueous extract treated group (P<0.05. Ethyl acetate layer of aqueous extract did not show obvious effects on the measured parameters. These findings suggest that water layer of aqueous extract 40 g/kg ameliorates microwave-reduced reproductive impairment.

  8. Application of {sup 1}H-NMR-based metabolomics for detecting injury induced by long-term microwave exposure in Wistar rats' urine

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Li-Feng; Peng, Rui-Yun; Wang, Shui-Ming; Gao, Ya-Bing; Dong, Ji; Zhao, Li; Li, Xiang; Zuo, Hong-Yan; Wang, Chang-Zhen [Beijing Institute of Radiation Medicine, Laboratory of Pathology, Beijing (China); Hu, Xiang-Jun [Beijing Institute of Radiation Medicine, Beijing (China); Gao, Rong-Lian [Beijing Institute of Radiation Medicine, Laser Medicine, Beijing (China); Su, Zhen-Tao [Beijing Institute of Radiation Medicine, Radiation Protection, Beijing (China); Feng, Xin-Xing [Chinese Academy of Medical Sciences, Endocrine and Cardiovascular Center, Fuwai Hospital and Cardiovascular Institute, Beijing (China)

    2012-07-15

    There has been growing public concern regarding exposure to microwave fields as a potential human health hazard. This study aimed to identify sensitive biochemical indexes for the detection of injury induced by microwave exposure. Male Wistar rats were exposed to microwaves for 6 min per day, 5 days per week over a period of 1 month at an average power density of 5 mW/cm{sup 2} (specific absorption rate of 2.1 W/kg). Urine specimens were collected over 24 h in metabolic cages at 7 days, 21 days, 2 months, and 6 months after exposure. {sup 1}H NMR spectroscopy data were analyzed using multivariate statistical techniques. Urine metabolic profiles of rats after long-term microwave exposure were significantly differentiated from those of sham-treated controls using principal component analysis or partial least squares discriminant analysis. Significant differences in low molecular weight metabolites (acetate, succinate, citrate, ketoglutarate, glucose, taurine, phenylalanine, tyrosine, and hippurate) were identified in the 5 mW/cm{sup 2} microwave exposure group compared with the sham-treated controls at 7 days, 21 days, and 2 months. Metabolites returned to normal levels by 6 months after exposure. These data indicated that these metabolites were related to the perturbations of energy metabolism particularly in the tricarboxylic acid cycle, and the metabolism of amino acids, monoamines, and choline in urine represent potential indexes for the detection of injury induced by long-term microwave exposure. (orig.)

  9. Enhanced Microwave Absorption Properties of Oriented Carbonyl Iron/Carbon Black Composite Induced by Shear Force

    Science.gov (United States)

    Min, Dandan; Zhou, Wancheng; Qing, Yuchang; Luo, Fa; Zhu, Dongmei

    2017-08-01

    Oriented carbonyl iron/carbon black (CI/CB) composite with enhanced microwave absorption properties was prepared by shear force which was applied to make the planes of CI parallel to each other. The effects of orientation, CB content and thickness on the microwave absorption properties were investigated. The measurement results showed that higher permeability and modest permittivity of the composite were obtained after CI orientation in a 2-18-GHz frequency range. The complex permittivity of the CI/CB composite increased with increasing CB content, which was mainly attributed to the interfacial polarization at the CI/resin/CB particle interfaces. The calculated microwave absorption properties indicated that the orientation plays an important role in decreasing the absorber thickness and broadening the absorption bandwidth. The oriented CI/CB composite containing 65 wt.% CI and 3.0 wt.% CB showed a wider absorption frequency range of 12.5 GHz from 5.5 GHz to 18 GHz with reflection loss (RL) below -5 dB at a thickness of 0.9 mm. This work offers a promising approach for the fabrication of microwave absorbing materials with thin thickness and an adjustable wider working frequency range.

  10. Short-duration exposure to 2.45 GHz microwave radiation induces ...

    African Journals Online (AJOL)

    ... disorganization in the testis of exposed group with increasing SARs. These results suggest that MW radiation has the potential to affect both male and female fertility adversely. Keywords: 2.45 GHz microwave radiation, histopathology, DNA single strand break, ovary, testis. African Journal of Biotechnology Vol. 12(2), pp.

  11. Extremely low-level microwaves attenuate immune imbalance induced by inhalation exposure to low-level toluene in mice.

    Science.gov (United States)

    Novoselova, Elena G; Glushkova, Olga V; Khrenov, Maxim O; Novoselova, Tatyana V; Lunin, Sergey M; Fesenko, Eugeny E

    2017-05-01

    To clarify whether extremely low-level microwaves (MW) alone or in combination with p38 inhibitor affect immune cell responses to inhalation exposure of mice to low-level toluene. The cytokine profile, heat shock proteins expression, and the activity of several signal cascades, namely, NF-κB, SAPK/JNK, IRF-3, p38 MAPK, and TLR4 were measured in spleen lymphocytes of mice treated to air-delivered toluene (0.6 mg/m 3 ) or extremely low-level microwaves (8.15-18 GHz, 1μW/cm 2 , 1 Hz swinging frequency) or combined action of these two factors. A single exposure to air-delivered low-level toluene induced activation of NF-κB, SAPK/JNK, IFR-3, p38 MAPK and TLR4 pathways. Furthermore, air toluene induced the expression of Hsp72 and enhanced IL-1, IL-6, and TNF-α in blood plasma, which is indicative of a pro-inflammatory response. Exposure to MW alone also resulted in the enhancement of the plasma cytokine values (e.g. IL-6, TNF-α, and IFN-γ) and activation of the NF-κB, MAPK p38, and especially the TLR4 pathways in splenic lymphocytes. Paradoxically, pre-exposure to MW partially recovered or normalized the lymphocyte parameters in the toluene-exposed mice, while the p38 inhibitor XI additionally increased protective activity of microwaves by down regulating MAPKs (JNK and p38), IKK, as well as expression of TLR4 and Hsp90-α. The results suggest that exposure to low-intensity MW at specific conditions may recover immune parameters in mice undergoing inhalation exposure to low-level toluene via mechanisms involving cellular signaling.

  12. Microwave Ovens

    Science.gov (United States)

    ... Products and Procedures Home, Business, and Entertainment Products Microwave Ovens Share Tweet Linkedin Pin it More sharing ... 1030.10 - Microwave Ovens Required Reports for the Microwave Oven Manufacturers or Industry Exemption from Certain Reporting ...

  13. Microwave engineering

    CERN Document Server

    Pozar, David M

    2012-01-01

    The 4th edition of this classic text provides a thorough coverage of RF and microwave engineering concepts, starting from fundamental principles of electrical engineering, with applications to microwave circuits and devices of practical importance.  Coverage includes microwave network analysis, impedance matching, directional couplers and hybrids, microwave filters, ferrite devices, noise, nonlinear effects, and the design of microwave oscillators, amplifiers, and mixers. Material on microwave and RF systems includes wireless communications, radar, radiometry, and radiation hazards. A large

  14. BEHAVIOR OF REACTION MIXTURES UNDER MICROWAVE CONDITIONS - USE OF SODIUM-SALTS IN MICROWAVE-INDUCED N-[F-18]FLUOROALKYLATIONS OF APORPHINE AND TETRALIN DERIVATIVES

    NARCIS (Netherlands)

    ZIJLSTRA, S; DEGROOT, TJ; KOK, LP; VISSER, GM; VAALBURG, W

    1993-01-01

    Microwave treatment combined with manipulation of the ionic strength of the reaction mixture increases the radiochemical yield dramatically of N-[F-18]fluoroalkylations of secondary amines as compared to thermal heating.

  15. IEEE conference record -- Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    This conference covers the following areas: computational plasma physics; vacuum electronic; basic phenomena in fully ionized plasmas; plasma, electron, and ion sources; environmental/energy issues in plasma science; space plasmas; plasma processing; ball lightning/spherical plasma configurations; plasma processing; fast wave devices; magnetic fusion; basic phenomena in partially ionized plasma; dense plasma focus; plasma diagnostics; basic phenomena in weakly ionized gases; fast opening switches; MHD; fast z-pinches and x-ray lasers; intense ion and electron beams; laser-produced plasmas; microwave plasma interactions; EM and ETH launchers; solid state plasmas and switches; intense beam microwaves; and plasmas for lighting. Separate abstracts were prepared for 416 papers in this conference.

  16. IEEE conference record -- Abstracts

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    This conference covers the following areas: computational plasma physics; vacuum electronic; basic phenomena in fully ionized plasmas; plasma, electron, and ion sources; environmental/energy issues in plasma science; space plasmas; plasma processing; ball lightning/spherical plasma configurations; plasma processing; fast wave devices; magnetic fusion; basic phenomena in partially ionized plasma; dense plasma focus; plasma diagnostics; basic phenomena in weakly ionized gases; fast opening switches; MHD; fast z-pinches and x-ray lasers; intense ion and electron beams; laser-produced plasmas; microwave plasma interactions; EM and ETH launchers; solid state plasmas and switches; intense beam microwaves; and plasmas for lighting. Separate abstracts were prepared for 416 papers in this conference

  17. Detection of carbon nanotubes in plant roots through microwave-induced heating

    Science.gov (United States)

    Irin, Fahmida; Shrestha, Babina; Canas, Jaclyn; Saed, Mohammad; Green, Micah

    2012-02-01

    We demonstrate a novel technique for quantitative detection of CNTs in biological samples by utilizing the thermal response of CNTs under microwave irradiation. In particular, rapid heating of CNTs due to microwave absorption was employed to quantify the amount of CNTs present in alfalfa plant roots. Alfalfa roots were prepared by injecting a known amount of CNTs (single walled and multi walled) and exposed to 30-50 W microwave power to generate calibration curves (temperature rise vs. CNT mass). These calibration curves serve as a characterization tool to determine the unknown amount of CNTs absorbed by alfalfa plant roots grown in CNT-laden soil with superior accuracy and sensitivity. Moreover, the threshold for detectable CNT concentration is much lower than common analytical methods of detecting nanomaterials, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. Considering the lack of effective detection methods for CNT uptake in plants, this method is not only unique but also practical, as it addresses a major problem in the field of nanotoxicology risk assessment.

  18. Welding of 3D-printed carbon nanotube-polymer composites by locally induced microwave heating.

    Science.gov (United States)

    Sweeney, Charles B; Lackey, Blake A; Pospisil, Martin J; Achee, Thomas C; Hicks, Victoria K; Moran, Aaron G; Teipel, Blake R; Saed, Mohammad A; Green, Micah J

    2017-06-01

    Additive manufacturing through material extrusion, often termed three-dimensional (3D) printing, is a burgeoning method for manufacturing thermoplastic components. However, a key obstacle facing 3D-printed plastic parts in engineering applications is the weak weld between successive filament traces, which often leads to delamination and mechanical failure. This is the chief obstacle to the use of thermoplastic additive manufacturing. We report a novel concept for welding 3D-printed thermoplastic interfaces using intense localized heating of carbon nanotubes (CNTs) by microwave irradiation. The microwave heating of the CNT-polymer composites is a function of CNT percolation, as shown through in situ infrared imaging and simulation. We apply CNT-loaded coatings to a 3D printer filament; after printing, microwave irradiation is shown to improve the weld fracture strength by 275%. These remarkable results open up entirely new design spaces for additive manufacturing and also yield new insight into the coupling between dielectric properties and radio frequency field response for nanomaterial networks.

  19. Damage effect and mechanism of the GaAs high electron mobility transistor induced by high power microwave

    Science.gov (United States)

    Yang, Liu; Chang-Chun, Chai; Yin-Tang, Yang; Jing, Sun; Zhi-Peng, Li

    2016-04-01

    In this paper, we present the damage effect and mechanism of high power microwave (HPM) on AlGaAs/GaAs pseudomorphic high-electron-mobility transistor (pHEMT) of low-noise amplifier (LNA). A detailed investigation is carried out by simulation and experiment study. A two-dimensional electro-thermal model of the typical GaAs pHEMT induced by HPM is established in this paper. The simulation result reveals that avalanche breakdown, intrinsic excitation, and thermal breakdown all contribute to damage process. Heat accumulation occurs during the positive half cycle and the cylinder under the gate near the source side is most susceptible to burn-out. Experiment is carried out by injecting high power microwave into GaAs pHEMT LNA samples. It is found that the damage to LNA is because of the burn-out at first stage pHEMT. The interiors of the damaged samples are observed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). Experimental results accord well with the simulation of our model. Project supported by the National Basic Research Program of China (Grant No. 2014CB339900) and the Open Fund of Key Laboratory of Complex Electromagnetic Environment Science and Technology, China Academy of Engineering Physics (Grant No. 2015-0214.XY.K).

  20. Feasibility of microwave-induced combustion for trace element determination in Engraulis anchoita by ICP-MS.

    Science.gov (United States)

    Maciel, Juliana V; Knorr, Camila L; Flores, Erico M M; Müller, Edson I; Mesko, Marcia F; Primel, Ednei G; Duarte, Fabio A

    2014-02-15

    A method based on microwave-induced combustion (MIC) was developed for fish (Engraulis anchoita) digestion and subsequent determination of As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, and Zn by inductively coupled plasma mass spectrometry (ICP-MS). A reflux step (5 min) was applied to improve absorption and recovery of analytes. Nitric acid was investigated as absorbing solution and suitable results were achieved using 5 mol L⁻¹ HNO₃. Microwave-assisted digestion in closed vessels using concentrated HNO₃ was also evaluated for comparison of results. Both sample preparation methods were considered suitable for sample digestion but MIC was preferable not only because diluted HNO3 can be used as absorbing solution but also because it provides higher efficiency of digestion and also better limits of detection. Accuracy was evaluated by the analysis of certified reference materials (DORM-2 and TORT-2) after MIC digestion with subsequent determination by ICP-MS. Agreement with certified values was better than 94%. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Microwave Induced Synthesis and Anti bacterial Activity of Some 6-(2-Hyroxy phenyl-4-(substituted phenyl -3-oxo-2, 3, 4, 5- tetrahydro-1H-indazoles

    Directory of Open Access Journals (Sweden)

    N. S. Rao

    2008-01-01

    Full Text Available The title compounds were synthesized by condensation of 2-hydroxy chalcones with ethylacetoacetate to get intermediate 3,5-diaryl-6-carbethoxy-2-cyclohexenone which were subsequently treated with hydrazine hydrate to afford the title compounds. All the transformation was carried out under microwave induced conditions. The synthesized compounds were screened for their antibacterial activity in vitro.

  2. Synthesis of Pd-coated FeCo@Fe/C core-shell nanoparticles: microwave-induced ‘top-down’ nanostructuring and decoration

    CSIR Research Space (South Africa)

    Fashedemi, OO

    2013-01-01

    Full Text Available We report a novel microwave-induced fast and efficient synthesis of sub-10 nm sized palladium-decorated FeCo@Fe core–shell nanoparticles (ca. 3–7 nm) from a large-sized FeCo@Fe (0.21–1.5 µm) precursor, suggesting ‘top-down’ nanosizing. The high...

  3. Microwave imaging

    CERN Document Server

    Pastorino, Matteo

    2010-01-01

    An introduction to the most relevant theoretical and algorithmic aspects of modern microwave imaging approaches Microwave imaging-a technique used in sensing a given scene by means of interrogating microwaves-has recently proven its usefulness in providing excellent diagnostic capabilities in several areas, including civil and industrial engineering, nondestructive testing and evaluation, geophysical prospecting, and biomedical engineering. Microwave Imaging offers comprehensive descriptions of the most important techniques so far proposed for short-range microwave imaging-in

  4. Microwave-assisted cross-linking of milk proteins induced by microbial transglutaminase

    OpenAIRE

    Chun-Chi Chen; Jung-Feng Hsieh

    2016-01-01

    We investigated the combined effects of microbial transglutaminase (MTGase, 7.0 units/mL) and microwave irradiation (MI) on the polymerization of milk proteins at 30??C for 3?h. The addition of MTGase caused the milk proteins to become polymerized, which resulted in the formation of components with a higher molecular-weight (>130?kDa). SDS-PAGE analysis revealed reductions in the protein content of ?-lactoglobulin (?-LG), ?S-casein (?S-CN), ?-casein (?-CN) and ?-casein (?-CN) to 50.4???2.9, 3...

  5. Microwave-induced co-tunneling in single electron tunneling transistors

    DEFF Research Database (Denmark)

    Ejrnaes, M.; Savolainen, M.; Manscher, M.

    2002-01-01

    on rubber bellows. Cross-talk was minimized by using individual coaxial lines between the sample and the room temperature electronics: The co-tunneling experiments were performed at zero DC bias current by measuring the voltage response to a very small amplitude 2 Hz current modulation with the gate voltage......The influence of microwaves on the co-tunneling in single electron tunneling transistors has been investigated as function of frequency and power in the temperature range from 150 to 500 mK. All 20 low frequency connections and the RF line were filtered, and the whole cryostat was suspended...

  6. Microwave induced hierarchical nanostructures on aramid fibers and their influence on adhesion properties in a rubber matrix

    Energy Technology Data Exchange (ETDEWEB)

    Palola, S., E-mail: sarianna.palola@tut.fi [Laboratory of Materials Science, Tampere University of Technology, P.O. Box 589, 33101, Tampere (Finland); Institute for Materials and Processes, School of Engineering, The University of Edinburgh, The King' s Buildings, Robert Stevenson Road, EH9 3FB Edinburgh (United Kingdom); Sarlin, E. [Laboratory of Materials Science, Tampere University of Technology, P.O. Box 589, 33101, Tampere (Finland); Kolahgar Azari, S.; Koutsos, V. [Institute for Materials and Processes, School of Engineering, The University of Edinburgh, The King' s Buildings, Robert Stevenson Road, EH9 3FB Edinburgh (United Kingdom); Vuorinen, J. [Laboratory of Materials Science, Tampere University of Technology, P.O. Box 589, 33101, Tampere (Finland)

    2017-07-15

    Highlights: • A novel method for creating nanostructures to aramid fiber surface is proposed. • The nanostructures enable mechanical interlocking at fiber-matrix interface. • A ∼250% increase in adhesion can be created with this method. - Abstract: Several commercial surface treatments are used to increase the adhesion between aramid fibers and the matrix material in composite structures but each of these has some limitations. The aim of this study is to address some of these limitations by developing a surface treatment method for aramid fibers that would not affect mechanical properties of the fibers negatively, could be used with any matrix material and that could withstand handling of the fibers and ageing. The method used is microwave assisted surface treatment that uses microwave radiation together with dry reactive chemicals to create hierarchical structures to the fiber surface and so makes it possible to control the adhesion properties of the fibers. SEM and AFM imaging, fiber tensile tests and modified bundle pull-out test were used to investigate the outcome of the surface treatment and measure adhesion between aramid fiber bundles and rubber. SEM and AFM imaging revealed that nanoscale deposits are formed on to the fiber surface which enable mechanical interlocking between the fiber and the matrix material. Fiber tensile tests showed that the surface treatment does not influence the tensile properties of the fiber negatively. Results from the bundle pull-out tests confirmed that this kind of method can lead up to 259% improvement in adhesion when compared to untreated aramid fibers in the rubber matrix.

  7. Mitigating acoustic heterogeneous effects in microwave-induced breast thermoacoustic tomography using multi-physical K-means clustering

    Science.gov (United States)

    Wang, Bingwen; Zhao, Zhiqin; Liu, Shuangli; Nie, Zaiping; Liu, Qinghuo

    2017-11-01

    Microwave-induced thermoacoustic tomography shows great potential for early-stage breast tumor detection, but imaging quality usually suffers due to acoustic heterogeneity of breast tissue. To mitigate this problem, conventional methods estimate the distribution of speeds of sound but at a heavy cost of system complexity or computation burden. We propose an imaging reconstruction method that incorporates dielectric and acoustic properties of tissues as a-priori information and reformulates the velocity estimation problem as a data clustering problem. The proposed method is validated by imaging anatomically realistic numerical breast phantoms and real biological tissues. Both simulation and experimental results demonstrate that the proposed method is robust and significantly improves image fidelity with less computational burden than conventional methods. These results make our approach a promising candidate for clinical breast cancer detection.

  8. Removal and sterilization of biofilms and planktonic bacteria by microwave-induced argon plasma at atmospheric pressure

    Science.gov (United States)

    Lee, Mi Hee; Park, Bong Joo; Jin, Soo Chang; Kim, Dohyun; Han, Inho; Kim, Jungsung; Hyun, Soon O.; Chung, Kie-Hyung; Park, Jong-Chul

    2009-11-01

    Microbial biofilms are a functional matrix of microbial cells, enveloped in polysaccharides, enzymes and virulence factors secreted by them that can develop on indwelling medical devices and biomaterials. Plasma sterilization has been widely studied in recent years for biological applications. In this study, we evaluated the possibility of removal and anti-recovery of biofilms by microwave-induced argon plasma at atmospheric pressure. We observed that all bacterial biofilms formatted by Gram-negative and Gram-positive bacteria are removed in less than 20 s, and the growth inhibitions of planktonic bacteria within biofilms are also confirmed by plasma exposure for 5 s. These results suggest that our plasma system can be applied to medical and biological fields where the removal of biofilms and their debris is required.

  9. Damage Simulation of a Random Aggregate Model Induced by Microwave under Different Discontinuous Ratios and Exposure Times

    Directory of Open Access Journals (Sweden)

    Yang Tang

    2016-01-01

    Full Text Available A random aggregate algorithmic method and a numerical model for two-phase materials (composed of quartz and plagioclase with different discontinuous ratios and irradiation times were studied based on the discrete element method using two-dimensional particle flow code (PFC2D. The results showed that this algorithm can simulate random irregular aggregate shapes. Furthermore, crack initiation and development and the coalescence process of microwave-induced material damage could be predicted using the discrete element method. After analysis of this study, the micro crack originated from the boundary of the high-absorption-phase plagioclase crystal and expanded around the plagioclase, extending into the quartz material. The crack morphology presented a radial network.

  10. Preparation of creating active carbon from cigarette filter waste using microwave-induced KOH activation

    Science.gov (United States)

    Hamzah, Yanuar; Umar, Lazuardi

    2017-05-01

    For the first time, cigarette filter waste, which is an environmental hazardous material, is used as basic material prepared for creating activated carbon (AC) via KOH chemical activation using a microwave input power of 630 W and irradiation time of 20 minutes. Active carbon was characterized by TGA, x-ray diffraction, scanning electron microscopy, energy dispersive x-ray, nitrogen adsorption-desorption, and absorption of methylene blue (MB). The results of x-ray diffraction showed that active carbon has a semi-crystalline structure with peaks of 2θ of 22.87° and 43.70°. Active carbon microstructure analysis showed that the layer height (Lc ) is inversely proportional to the width of the layer (La ), and the distance between the two layers is d002 and d100 , which depends significantly on the ratio of AC: KOH. It was found that the optimum BET surface area and adsorption capacity for MB were 328.13 m2 / g and 88.76 m2 / g, respectively. The results revealed the potential to prepare activated carbon from cigarette filter waste using microwave irradiation.

  11. [DNA damage and repair induced by acute exposure of microwave from mobile phone on cultured human lens epithelial cells].

    Science.gov (United States)

    Sun, Li-xia; Yao, Ke; Jiang, Huai; He, Ji-liang; Lu, De-qiang; Wang, Kai-jun; Li, Hong-wu

    2006-12-01

    To investigate the effects of acute exposure of low-power 217 Hz modulated 1. 8 GHz microwave radiation on the DNA damage of human lens epithelial cells (hLECs) and repair. Cultured hLECs were exposed to 217 Hz modulated 1. 8 GHz microwave radiation at SAR (specific absorption rate) of 1. 0, 2. 0, 3. O0 and 4. 0 W/kg for 2 hours in an sXc-1800 incubator and irradiate system, the DNA single strand breaks were detected with comet assay ( single-cell gel electrophoresis) in sham-irradiated cells and irradiated cells incubated for varying periods: 0, 30 and 60 minutes after irradiation. Images of comets were digitized and analyzed using an Imagine-pro plus software, and the indexes used in this study were tail length (TL) and tail moment (TM). BrdU was added into the medium with additional one hour incubation after radiation, the cell proliferation rate was determined using a BrdU-kit. The difference of DNA-breaks between the exposure and sham exposure groups induced by 1.0 and 2.0 W/kg irradiation were not significant in each time points (P > 0.05) ; there were significant difference in both groups at the exposure dose of 3. 0 and 4. 0 W/kg immediately and at the time of 30 minutes after irradiation (P 0. 05) compared with control, but the evidence of significant DNA damage still existed in 4. 0 W/kg group at the same time point. Cell proliferation rate had no significant difference when the application of SAR was 0. 05) , however the cell proliferation was decreased significantly at the dose of 4. 0 W/kg irradiation ( P < 0. 01). No effective DNA damage was induced using comet assay after 2 hours irradiation of 1. 8 GHz microwave on hLECs at the dose SAR < or = 3.0 W/kg. 4.0 W/kg irradiation caused significantly DNA damage and inhibition of hLECs proliferation.

  12. Abstract algebra

    CERN Document Server

    Garrett, Paul B

    2007-01-01

    Designed for an advanced undergraduate- or graduate-level course, Abstract Algebra provides an example-oriented, less heavily symbolic approach to abstract algebra. The text emphasizes specifics such as basic number theory, polynomials, finite fields, as well as linear and multilinear algebra. This classroom-tested, how-to manual takes a more narrative approach than the stiff formalism of many other textbooks, presenting coherent storylines to convey crucial ideas in a student-friendly, accessible manner. An unusual feature of the text is the systematic characterization of objects by universal

  13. IEEE conference record--Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    The following topics were covered in this meeting: basic plasma phenomena and plasma waves; plasma diagnostics; space plasma diagnostics; magnetic fusion; electron, ion and plasma sources; intense electron and ion beams; intense beam microwaves; fast wave M/W devices; microwave plasma interactions; plasma focus; ultrafast Z-pinches; plasma processing; electrical gas discharges; fast opening switches; magnetohydrodynamics; electromagnetic and electrothermal launchers; x-ray lasers; computational plasma science; solid state plasmas and switches; environmental/energy issues in plasma science; vacuum electronics; plasmas for lighting; gaseous electronics; and ball lightning and other spherical plasmas. Separate abstracts were prepared for 278 papers of this conference.

  14. Article Abstract

    African Journals Online (AJOL)

    Abstract. Simple learning tools to improve clinical laboratory practical skills training. B Taye, BSc, MPH. Addis Ababa University, College of Health Sciences, Addis Ababa, ... concerns about the competence of medical laboratory science graduates. ... standardised practical learning guides and assessment checklists would.

  15. Abstract Introduction

    African Journals Online (AJOL)

    Abstract. Cyclic ovarian activity and plasma progesterone (P4) concentrations were assessed for 179 days in 5. (free grazing) and 6 (free grazing + high energy and protein-supplemented) normocyclic donkeys. In addition, plasma p4 and cortisol were measured in blood samples collected at J5·min intervals in the.

  16. Abstract Introduction

    African Journals Online (AJOL)

    cce

    Abstract. Hemoglobin is a tetrameric protein which is able to dissociate into dimers. The dimers can in turn dissociate into tetramers. It has been found that dimers are more reactive than tetramers. The difference in the reactivity of these two species has been used to determine the tetramer- dimer dissociation constant of ...

  17. Focused microwave-induced combustion for digestion of botanical samples and metals determination by ICP OES and ICP-MS.

    Science.gov (United States)

    Barin, J S; Pereira, J S F; Mello, P A; Knorr, C L; Moraes, D P; Mesko, M F; Nóbrega, J A; Korn, M G A; Flores, E M M

    2012-05-30

    The advantages and shortcomings of focused microwave-induced combustion (FMIC) for digestion of plant samples were studied. The effects of sample mass, absorbing solution, oxygen gas flow-rate, and time of reflux step on recoveries of major, minor and trace metals were systematically evaluated. Afterwards, Al, Ba, Ca, Co, Cr, Cu, Mg, Mn, Ni, Sr, V, and Zn were determined by inductively coupled plasma optical emission spectrometry (ICP OES) and by inductively coupled plasma mass spectrometry (ICP-MS). The main advantages of FMIC when compared to microwave-assisted wet digestion (MAWD) and focused-microwave-assisted wet digestion (FMAWD) are the possibility to digest larger masses of samples (up to 3g) using shorter heating times and diluted nitric acid solution for absorbing all analytes. Using the selected experimental conditions for FMIC, residual carbon content was lower than 0.7% for all samples and relative standard deviation (RSD) varied from 1.5 to 14.1%. Certified reference materials (NIST 1515 apple leaves and NIST 1547 peach leaves) were used for checking accuracy and determined values for all metals were in agreement with certified values at a 95% confidence level. No statistical difference (ANOVA, 95% of confidence level) was observed for results obtained by FMIC, FMAWD, and MAWD. Limits of detection were lower when using FMIC in the range of 0.02-0.15 μg g(-1) for ICP OES and 0.001-0.01 μg g(-1) for ICP-MS, which were about 3 and 6 times lower than the values obtained by FMAWD and MAWD, respectively. It is important to point out that FMIC was a suitable sample preparation method for major, minor and trace metals by both determination techniques (ICP OES and ICP-MS). Additionally, since it allows lower LODs (because up to 3g of sample can be digested) and diluted acid solutions are used (without any further dilution), the use of ICP-MS is not mandatory. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Microwave Irradiation

    Indian Academy of Sciences (India)

    Microwave Irradiation. Way to Eco-friendly, Green Chemistry. Rashmi Sanghi. This article highlights with examples, the usefulness of microwaves for carrying out a'variety of organic transfor- mations. Introduction and Background. The rapid heating of food in the kitchen using microwave ovens prompted a number of ...

  19. Imaging-guided synergetic therapy of orthotopic transplantation tumor by superselectively arterial administration of microwave-induced microcapsules.

    Science.gov (United States)

    Tang, Shunsong; Fu, Changhui; Tan, Longfei; Liu, Tianlong; Mao, Jingsong; Ren, Xiangling; Su, Hongying; Long, Dan; Chai, Qianqian; Huang, Zhongbing; Chen, Xudong; Wang, Jingzhuo; Ren, Jun; Meng, Xianwei

    2017-07-01

    It is an ambitious target to improve overall Hepatocellular Carcinoma therapeutic effects. Recently, MW ablation has emerged as a powerful thermal ablation technique, affording favorable survival with excellent local tumor control. To achieve better therapeutic effects of MW ablation, MW sensitizers are prepared for enhanced MW ablation to preferentially heat tumor territory. However, it is still not practicable for treatment of the orthotopic transplantation tumor. Herein, biocompatible and degradable methoxy poly(ethylene glycol)-poly(lactic-co-glycolic acid) (mPEG-PLGA) microcapsules with hierarchical structure have been designed for microwave-induced tumor therapy. Chemical drug doxorubicin hydrochloride (DOX·HCl), microwave (MW) sensitizers and CT imaging contrast MoS 2 nanosheets and MR imaging contrast Fe 3 O 4 nanoparticles are co-incorporated into the microcapsules. In vitro/vivo MR/CT dual-modal imaging results prove the potential application for guiding synergetic therapy and predicting post-therapy tumor progression in the orthotopic transplantation tumor model. After blocking the tumor-feeding arteries, these microcapsules not only exclude the cooling effect by cutting off the blood flow but also enhance MW heating conversion at tumor site. The focused MW heating makes microcapsules mollescent or ruptured and releases DOX·HCl from the microcapsules, achieving the controlled release of drugs for chemical therapy. Compared with MW ablation, 29.4% increase of necrosis diameter of normal liver in rabbit is obtained under MW ablation combined with transcatheter arterial blocking, and the average size of necrosis and inhibition rate of VX-2 liver orthotopic transplantation tumor in rabbit has increased by 129.33% and 73.46%. Moreover, it is proved that the superselectively arterial administration of the as-prepared microcapsules has no recognizable toxicity on the animals. Therefore, this research provides a novel strategy for the construction of MW-induced

  20. Microwave radiation (2.45 GHz)-induced oxidative stress: Whole-body exposure effect on histopathology of Wistar rats.

    Science.gov (United States)

    Chauhan, Parul; Verma, H N; Sisodia, Rashmi; Kesari, Kavindra Kumar

    2017-01-01

    Man-made microwave and radiofrequency (RF) radiation technologies have been steadily increasing with the growing demand of electronic appliances such as microwave oven and cell phones. These appliances affect biological systems by increasing free radicals, thus leading to oxidative damage. The aim of this study was to explore the effect of 2.45 GHz microwave radiation on histology and the level of lipid peroxide (LPO) in Wistar rats. Sixty-day-old male Wistar rats with 180 ± 10 g body weight were used for this study. Animals were divided into two groups: sham exposed (control) and microwave exposed. These animals were exposed for 2 h a day for 35 d to 2.45 GHz microwave radiation (power density, 0.2 mW/cm 2 ). The whole-body specific absorption rate (SAR) was estimated to be 0.14 W/kg. After completion of the exposure period, rats were sacrificed, and brain, liver, kidney, testis and spleen were stored/preserved for determination of LPO and histological parameters. Significantly high level of LPO was observed in the liver (p microwave radiation. Also histological changes were observed in the brain, liver, testis, kidney and spleen after whole-body microwave exposure, compared to the control group. Based on the results obtained in this study, we conclude that exposure to microwave radiation 2 h a day for 35 d can potentially cause histopathology and oxidative changes in Wistar rats. These results indicate possible implications of such exposure on human health.

  1. On cloud ice induced absorption and polarisation effects in microwave limb sounding

    Directory of Open Access Journals (Sweden)

    P. Eriksson

    2011-06-01

    Full Text Available Microwave limb sounding in the presence of ice clouds was studied by detailed simulations, where clouds and other atmospheric variables varied in three dimensions and the full polarisation state was considered. Scattering particles were assumed to be horizontally aligned oblate spheroids with a size distribution parameterized in terms of temperature and ice water content. A general finding was that particle absorption is significant for limb sounding, which is in contrast to the down-looking case, where it is usually insignificant. Another general finding was that single scattering can be assumed for cloud optical paths below about 0.1, which is thus an important threshold with respect to the complexity and accuracy of retrieval algorithms. The representation of particle sizes during the retrieval is also discussed. Concerning polarisation, specific findings were as follows: Firstly, no significant degree of circular polarisation was found for the considered particle type. Secondly, for the ±45° polarisation components, differences of up to 4 K in brightness temperature were found, but differences were much smaller when single scattering conditions applied. Thirdly, the vertically polarised component has the smallest cloud extinction. An important goal of the study was to derive recommendations for future limb sounding instruments, particularly concerning their polarisation setup. If ice water content is among the retrieval targets (and not just trace gas mixing ratios, then the simulations show that it should be best to observe any of the ±45° and circularly polarised components. These pairs of orthogonal components also make it easier to combine information measured from different positions and with different polarisations.

  2. Microwave-assisted cross-linking of milk proteins induced by microbial transglutaminase

    Science.gov (United States)

    Chen, Chun-Chi; Hsieh, Jung-Feng

    2016-12-01

    We investigated the combined effects of microbial transglutaminase (MTGase, 7.0 units/mL) and microwave irradiation (MI) on the polymerization of milk proteins at 30 °C for 3 h. The addition of MTGase caused the milk proteins to become polymerized, which resulted in the formation of components with a higher molecular-weight (>130 kDa). SDS-PAGE analysis revealed reductions in the protein content of β-lactoglobulin (β-LG), αS-casein (αS-CN), κ-casein (κ-CN) and β-casein (β-CN) to 50.4 ± 2.9, 33.5 ± 3.0, 4.2 ± 0.5 and 1.2 ± 0.1%, respectively. The use of MTGase in conjunction MI with led to a 3-fold increase in the rate of milk protein polymerization, compared to a sample that contained MTGase but did not undergo MI. Results of two-dimensional gel electrophoresis (2-DE) indicated that κ-CN, β-CN, a fraction of serum albumin (SA), β-LG, α-lactalbumin (α-LA), αs1-casein (αs1-CN), and αs2-casein (αs2-CN) were polymerized in the milk, following incubation with MTGase and MI at 30 °C for 1 h. Based on this result, the combined use of MTGase and MI appears to be a better way to polymerize milk proteins.

  3. Behaviour of Bichromatic Microwave Induced Magnetoresistance Oscillations in the High Mobility GaAs/AlGaAs 2D electron System

    International Nuclear Information System (INIS)

    Gunawardana, Binuka; Liu, Han-Chun; Samaraweera, Rasanga L.; Mani, R.G.; Reichl, C.; Wegscheider, W

    2017-01-01

    Microwave radiation-induced magneto-resistance oscillations are examined under bichromatic excitation for various frequency combinations in order to obtain a better understanding of the lineshape observed in the dual excitation experiment of the high mobility GaAs/AlGaAs 2D electron system. Here, we examine superposition- or lack thereof- in the lineshape observed in the bichromatic experiment, and report a trend observed between the monochromatic and bichromatic responses of the oscillatory diagonal resistance. (paper)

  4. GSM microwaves and 50 Hz electromagnetic field induce stress response but not apoptosis in human lymphocytes from hypersensitive and healthy persons

    International Nuclear Information System (INIS)

    Belyaev, I.; Hillert, L.; Prototpopova, M.; Selivanova, G.; Harms-Ringdahl, M.

    2003-01-01

    We used specific conditions of exposure to microwaves from a GSM (global system for mobile communication) mobile phone (915 MHz, SAR=0.4 mW/g) and 50 Hz electromagnetic field (EMF, 15 μT amplitude) to investigate the response of lymphocytes from healthy subjects and from persons reporting hypersensitivity to EMF. The groups of hypersensitive and healthy donors were matched by gender and age and the data were analyzed in blind. The changes in chromatin conformation were measured with the method of anomalous viscosity time dependencies (AVTD). 53BP1 protein, which has been shown to co-localize in foci with DNA double strand breaks (DSB), was analyzed by immunostaining in situ. Exposure either to GSM microwaves or EMF/50 Hz resulted in significant condensation of chromatin, which was similar to the effect of heat shock at 41deg C. These effects varied between donors with a trend for prolonged condensation of chromatin in the cells from hypersensitive subjects. Cells from subjects, which were classified as pronounced hypersensitivity, responded to GSM /ELF stronger than cells from matched control subjects, but these differences in responses need to be confirmed in a larger study group. Neither GSM nor ELF exposure induced formation of 53BP1 foci. In contrary, distinct decrease in background level of 53BP1 signaling was observed upon these exposures as well as after heat shock treatments. This decrease correlated with the AVTD data and may indicate decrease in accessibility of 53BP1 to antibodies because of stress-induced chromatin condensation. No apoptosis was induced by exposure to ELF/50 Hz and GSM microwaves. In conclusion, ELF magnetic fields and GSM microwaves under specified conditions of exposure induced stress response in lymphocytes from healthy and hypersensitive donors

  5. Plasma-based determination of inorganic contaminants in waste of electric and electronic equipment after microwave-induced combustion

    Energy Technology Data Exchange (ETDEWEB)

    Mello, Paola A.; Diehl, Lisarb O.; Oliveira, Jussiane S.S.; Muller, Edson I. [Departamento de Química, Universidade Federal de Santa Maria, Av. Roraima, 1000, 97105-900, Santa Maria (Brazil); Mesko, Marcia F. [Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Campus Capão do Leão, 96900-010 Pelotas, RS (Brazil); Flores, Erico M.M., E-mail: ericommf@gmail.com [Departamento de Química, Universidade Federal de Santa Maria, Av. Roraima, 1000, 97105-900, Santa Maria (Brazil)

    2015-03-01

    A systematic study was performed for the determination of inorganic contaminants in polymeric waste from electrical and electronic equipment (EEE) for achieving an efficient digestion to minimize interferences in determination using plasma-based techniques. The determination of As, Br, Cd, Co, Cr, Cu, Ni, Pb, Sb, and Zn by inductively coupled plasma mass spectrometry (ICP-MS) and also by inductively coupled plasma optical emission spectrometry (ICP OES) was carried out after digestion using microwave-induced combustion (MIC). Arsenic and Hg were determined by flow-injection chemical vapor generation inductively coupled plasma mass spectrometry (FI-CVG-ICP-MS). Dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS) with ammonia was also used for Cr determination. The suitability of MIC for digestion of sample masses up to 400 mg was demonstrated using microcrystalline cellulose as aid for combustion of polymers from waste of EEEs that usually contain flame retardants that impair the combustion. The composition and concentration of acid solutions (HNO{sub 3} or HNO{sub 3} plus HCl) were evaluated for metals and metalloids and NH{sub 4}OH solutions were investigated for Br absorption. Accuracy was evaluated by comparison of results with those obtained using high pressure microwave-assisted wet digestion (HP-MAWD) and also by the analysis of certified reference material (CRM) of polymer (EC680k—low-density polyethylene). Bromine determination was only feasible using digestion by MIC once losses were observed when HP-MAWD was used. Lower limits of detection were obtained for all analytes using MIC (from 0.005 μg g{sup −1} for Co by ICP-MS up to 3.120 μg g{sup −1} for Sb by ICP OES) in comparison to HP-MAWD due to the higher sample mass that can be digested (400 mg) and the use of diluted absorbing solutions. The combination of HNO{sub 3} and HCl for digestion showed to be crucial for quantitative recovery of some elements, as Cr and Sb

  6. Coherent control and storage of a microwave pulse in a one-dimensional array of artificial atoms using the Autler-Townes effect and electromagnetically induced transparency

    Science.gov (United States)

    Ayaz, M. Q.; Waqas, Mohsin; Qamar, Sajid; Qamar, Shahid

    2018-02-01

    In this paper we propose a scheme for coherent control and storage of a microwave pulse in superconducting circuits exploiting the idea of electromagnetically induced transparency (EIT) and the Aulter-Townes (AT) effect. We show that superconducting artificial atoms in a four-level tripod configuration act as EIT based coherent microwave (μ w ) memories with gain features, when they are attached to a one-dimensional transmission line. These atoms are allowed to interact with three microwave fields, such that there are two control fields and one probe field. Our proposed system works in such a way that one control field with large Rabi frequency when interacting with atoms, produces the AT effect. While the second control field with relatively small Rabi frequency produces EIT in one of the absorption windows produced due to the AT splitting for the weak probe field. The group velocity of the probe pulse reduces significantly through this EIT window. Interestingly, the output intensity of the probe pulse increases as we increase the number of artificial atoms. Our results show that the probe microwave pulse can be stored and retrieved with high fidelity.

  7. Microwave-induced activation of additional active edge sites on the MoS2 surface for enhanced Hg0 capture

    Science.gov (United States)

    Zhao, Haitao; Mu, Xueliang; Yang, Gang; Zheng, Chengheng; Sun, Chenggong; Gao, Xiang; Wu, Tao

    2017-10-01

    In recent years, significant effort has been made in the development of novel materials for the removal of mercury from coal-derived flue gas. In this research, microwave irradiation was adopted to induce the creation of additional active sites on the MoS2 surface. The results showed that Hg0 capture efficiency of the adsorbent containing MoS2 nanosheets being microwave treated was as high as 97%, while the sample prepared via conventional method only showed an efficiency of 94% in its first 180 min testing. After the adsorbent was treated by microwave irradiation for 3 more times, its mercury removal efficiency was still noticeably higher than that of the sample prepared via conventional method. Characterization of surface structure of the MoS2 containing material together with DFT study further revealed that the (001) basal planes of MoS2 crystal structure were cracked into (100) edge planes (with an angle of approximately 75°) under microwave treatment, which subsequently resulted in the formation of additional active edge sites on the MoS2 surface and led to the improved performance on Hg0 capture.

  8. Protective Effects Induced by Microwave-Assisted Aqueous Harpagophytum Extract on Rat Cortex Synaptosomes Challenged with Amyloid β-Peptide.

    Science.gov (United States)

    Ferrante, Claudio; Recinella, Lucia; Locatelli, Marcello; Guglielmi, Paolo; Secci, Daniela; Leporini, Lidia; Chiavaroli, Annalisa; Leone, Sheila; Martinotti, Sara; Brunetti, Luigi; Vacca, Michele; Menghini, Luigi; Orlando, Giustino

    2017-08-01

    Harpagophytum procumbens is a plant species that displays anti-inflammatory properties in multiple tissues. The iridoid glycosides arpagoside, harpagide, and procumbide appear to be the most therapeutically important constituents. In addition, harpagoside treatment exerted neuroprotective effects both in vitro and in vivo. Considering these findings, the aim of the present work is to explore the possible protective role of the previously described microwave-assisted aqueous extract of H. procumbens on rat hypothalamic (Hypo-E22) cells, and in rat cortex challenged with amyloid β-peptide (1-40). In this context, we assayed the protective effects induced by H. procumbens by measuring the levels of malondialdehyde, 3-hydroxykynurenine (3-HK), brain-derived neurotrophic factor, and tumor necrosis factor-α, 3-HK. Finally, we evaluated the effects of H. procumbens treatment on cortex levels of dopamine, norepinephrine, and serotonin. H. procumbens extract was well tolerated by Hypo-E22 cells and upregulated brain-derived neurotrophic factor gene expression but down-regulated tumor necrosis factor-α gene expression. In addition, the extract reduced amyloid β-peptide stimulation of malondialdehyde and 3-HK and blunted the decrease of dopamine, norepinephrine, and serotonin, in the cortex. In this context, our work supports further studies for the evaluation and confirmation of Harpagophytum in the management of the clinical symptoms related to Alzheimer's disease. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  9. The microwave induced plasma with optical emission spectrometry (MIP-OES) in 23 elements determination in geological samples.

    Science.gov (United States)

    Niedzielski, P; Kozak, L; Wachelka, M; Jakubowski, K; Wybieralska, J

    2015-01-01

    The article presents the optimisation, validation and application of the microwave induced plasma optical emission spectrometry (MIP-OES) dedicated for a routine determination of Ag, Al, B, Ba, Bi, Ca, Cd, Cr, Cu, Fe, Ga, In, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sr, Tl, Zn, in the geological samples. The three procedures of sample preparation has been proposed: sample digestion with the use of hydrofluoric acid for determination of total concentration of elements, extraction by aqua regia for determination of the quasi-total element concentration and extraction by hydrochloric acid solution to determine contents of the elements in acid leachable fraction. The detection limits were on the level 0.001-0.121 mg L(-1) (from 0.010-0.10 to 1.2-12 mg kg(-1) depend on the samples preparation procedure); the precision: 0.20-1.37%; accuracy 85-115% (for recovery for certified standards materials analysis and parallel analysis by independent analytical techniques: X-ray fluorescence (XRF) and flame absorption spectrometry (FAAS)). The conformity of the results obtained by MIP-OES analytical procedures with the results obtained by XRF and FAAS analysis allows to propose the procedures for studies of elemental composition of the fraction of the geological samples. Additionally, the MIP-OES technique is much less expensive than ICP techniques and much less time-consuming than AAS techniques. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Short-duration exposure to 2.45 GHz microwave radiation induces ...

    African Journals Online (AJOL)

    OBEMBE

    radiation induces DNA damage in Sprague Dawley rat's reproductive ... affect both male and female fertility adversely. ... 4% relative humidity. Exposures were whole body irradiation with the animal at 12 cm from the MW antenna of dimensions 12 x 5 cm. The animals were divided into ten groups of three males and three.

  11. Microwave undulator

    International Nuclear Information System (INIS)

    Batchelor, K.

    1986-03-01

    The theory of a microwave undulator utilizing a plane rectangular waveguide operating in the TE/sub 10n/ mode and other higher order modes is presented. Based on this, a possible undulator configuration is analyzed, leading to the conclusion that the microwave undulator represents a viable option for undulator wavelength down to about 1 cm where peak voltage and available microwave power considerations limit effectiveness. 4 refs., 4 figs

  12. Direct current voltage induced by microwave signal in a ferromagnetic wire

    OpenAIRE

    Yamaguchi, A.; Motoi, K.; Miyajima, H.; Nakatani, Y.

    2007-01-01

    Experimental results of rectification of a constant wave radio frequency (RF) current flowing in a single-layered ferromagnetic wire are presented. We show that a detailed external magnetic field dependence of the RF current induced a direct-current voltage spectrum. The mechanism of the rectification is discussed in a term of the spin transfer torque, and the rectification is closely related to resonant spin wave excitation with the assistant of the spin-polarized RF current. The micromagnet...

  13. Microwave Microscope

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Makes ultra-high-resolution field measurements. The Microwave Microscope (MWM) has been used in support of several NRL experimental programs involving sea...

  14. Synthesis of polymer-derived ceramic Si(B)CN-carbon nanotube composite by microwave-induced interfacial polarization.

    Science.gov (United States)

    Bhandavat, R; Kuhn, W; Mansfield, E; Lehman, J; Singh, G

    2012-01-01

    We demonstrate synthesis of a polymer-derived ceramic (PDC)-multiwall carbon nanotube (MWCNT) composite using microwave irradiation at 2.45 GHz. The process takes about 10 min of microwave irradiation for the polymer-to-ceramic conversion. The successful conversion of polymer coated carbon nanotubes to ceramic composite is chemically ascertained by Fourier transform-infrared and X-ray photoelectron spectroscopy and physically by thermogravimetric analysis and transmission electron microscopy characterization. Frequency dependent dielectric measurements in the S-Band (300 MHz to 3 GHz) were studied to quantify the extent of microwave-CNT interaction and the degree of selective heating available at the MWCNT-polymer interface. Experimentally obtained return loss of the incident microwaves in the specimen explains the reason for heat generation. The temperature-dependent permittivity of polar molecules further strengthens the argument of internal heat generation. © 2011 American Chemical Society

  15. Cosmic Strings and Their Induced Non-Gaussianities in the Cosmic Microwave Background

    Directory of Open Access Journals (Sweden)

    Christophe Ringeval

    2010-01-01

    small fraction of the CMB angular power spectrum, cosmic strings could actually be the main source of its non-Gaussianities. In this paper, after having reviewed the basic cosmological properties of a string network, we present the signatures Nambu-Goto cosmic strings would induce in various observables ranging from the one-point function of the temperature anisotropies to the bispectrum and trispectrum. It is shown that string imprints are significantly different than those expected from the primordial type of non-Gaussianity and could therefore be easily distinguished.

  16. BALWOIS: Abstracts

    International Nuclear Information System (INIS)

    Morell, Morell; Todorovik, Olivija; Dimitrov, Dobri

    2004-01-01

    anthropogenic pressures and international shared water. Here are the 320 abstracts proposed by authors and accepted by the Scientific Committee. More than 200 papers are presented during the Conference on 8 topics related to Hydrology, Climatology and Hydro biology: - Climate and Environment; - Hydrological regimes and water balances; - Droughts and Floods; -Integrated Water Resources Management; -Water bodies Protection and Eco hydrology; -Lakes; -Information Systems for decision support; -Hydrological modelling. Papers relevant to INIS are indexed separately

  17. Conventional and microwave induced pyrolysis of coffee hulls for the production of a hydrogen rich fuel gas

    OpenAIRE

    Dominguez, Antonio; Menendez, Angel; Fernandez, Yolanda; Pis, Jose; Valente Nabais, Joao; Carrott, Peter; Carrott, Manuela

    2007-01-01

    This paper describes the conventional and microwave-assisted pyrolysis of coffee hulls at 500, 800 and 1000 8C. The influence of the pyrolysis method and temperature on the product yields and on the characteristics of the pyrolysis products is discussed. It was found that the pyrolysis of this particular residue gives rise to a larger yield of the gas fraction compared to the other fractions, even at relatively low temperatures. A comparison of microwave-assisted pyrolysis and conven...

  18. Synthesis of nitrogen-doped graphene via solid microwave method

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Li, E-mail: zhangli379@sohu.com [School of Electrical Engineering, Dalian University of Technology, Dalian, Liaoning 116024 (China); Ji, Bingcheng, E-mail: debbo.jee@outlook.com [School of Electrical Engineering, Dalian University of Technology, Dalian, Liaoning 116024 (China); Wang, Kai [School of Electrical Engineering, Dalian University of Technology, Dalian, Liaoning 116024 (China); Song, Jinyan [School of Information Engineering, Dalian Ocean University, Dalian, Liaoning 116024 (China)

    2014-07-01

    Graphical abstract: - Highlights: • A direct solid microwave method is developed to prepare nitrogen-doped graphene. • The method consists of two steps, namely the functionalization and microwave irradiation. • Melamine can serve as not only functionalizing agent but also nitrogen source. - Abstract: In this paper, we propose a solid microwave-mediated method for scalable production of nitrogen-doped graphene sheets (NGS) using low-cost industrial material melamine as functionalizing agent and nitrogen source. The strong interaction of microwaves with graphene oxide has been fully utilized to generate in situ heating that induces the decompose melamine and nitrogen doping of graphene. The morphology, structure, and components of the as-produced nitrogen-doped graphene are characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), Brunauer–Emmett–Teller (BET), pore-size distribution (PSD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectra (XPS), X-ray diffraction (XRD), and Raman spectroscopy. The results show NGS can be successfully synthesized via this strategy.

  19. Microwave Induced Welding of Carbon Nanotube-Thermoplastic Interfaces for Enhanced Mechanical Strength of 3D Printed Parts

    Science.gov (United States)

    Sweeney, Charles; Lackey, Blake; Saed, Mohammad; Green, Micah

    Three-dimensional (3D) printed parts produced by fused-filament fabrication of a thermoplastic polymer have become increasingly popular at both the commercial and consumer level. The mechanical integrity of these rapid-prototyped parts however, is severely limited by the interfillament bond strength between adjacent extruded layers. In this report we propose for the first time a method for welding thermoplastic interfaces of 3D printed parts using the extreme heating response of carbon nanotubes (CNTs) to microwave energy. To achieve this, we developed a coaxial printer filament with a pure polylactide (PLA) core and a CNT composite sheath. This produces parts with a thin electrically percolating network of CNTs at the interfaces between adjacent extruded layers. These interfaces are then welded together upon microwave irradiation at 2.45GHz. Our patent-pending method has been shown to increase the tensile toughness by 1000% and tensile strength by 35%. We investigated the dielectric properties of the PLA/CNT composites at microwave frequencies and performed in-situ microwave thermometry using a forward-looking infrared (FLIR) camera to characterize the heating response of the PLA/CNT composites upon microwave irradiation.

  20. Microwave Measurements

    CERN Document Server

    Skinner, A D

    2007-01-01

    The IET has organised training courses on microwave measurements since 1983, at which experts have lectured on modern developments. Their lecture notes were first published in book form in 1985 and then again in 1989, and they have proved popular for many years with a readership beyond those who attended the courses. The purpose of this third edition of the lecture notes is to bring the latest techniques in microwave measurements to this wider audience. The book begins with a survey of the theory of current microwave circuits and continues with a description of the techniques for the measureme

  1. Microwave photonics

    CERN Document Server

    Lee, Chi H

    2006-01-01

    Wireless, optical, and electronic networks continue to converge, prompting heavy research into the interface between microwave electronics, ultrafast optics, and photonic technologies. New developments arrive nearly as fast as the photons under investigation, and their commercial impact depends on the ability to stay abreast of new findings, techniques, and technologies. Presenting a broad yet in-depth survey, Microwave Photonics examines the major advances that are affecting new applications in this rapidly expanding field.This book reviews important achievements made in microwave photonics o

  2. Ceramic matrix composites by microwave assisted CVI

    International Nuclear Information System (INIS)

    Currier, R.P.; Devlin, D.J.

    1993-01-01

    Chemical vapor infiltration (CVI) processes for producing continuously reinforced ceramic composites are reviewed. Potential advantages of microwave assisted CVI are noted and numerical studies of microwave assisted CVI are reviewed. The models predict inverted thermal gradients in fibrous ceramic preforms subjected to microwave radiation and suggest processing strategies for achieving uniformly dense composites. Comparisons are made to experimental results on silicon-based composite systems. The role played by the relative ability of fiber and matrix to dissipate microwave energy is noted. Results suggest that microwave induced inverted gradients can be exploited to promote inside-out densification. 10 refs., 2 figs

  3. Microwave photonics

    CERN Document Server

    Lee, Chi H

    2013-01-01

    Microwave photonics continues to see rapid growth. The integration of optical fiber and wireless networks has become a commercial reality and is becoming increasingly pervasive. Such hybrid technology will lead to many innovative applications, including backhaul solutions for mobile networks and ultrabroadband wireless networks that can provide users with very high bandwidth services. Microwave Photonics, Second Edition systematically introduces important technologies and applications in this emerging field. It also reviews recent advances in micro- and millimeter-wavelength and terahertz-freq

  4. Athermal alterations in the structure in the canalicular membrane and ATPase activity induced by thermal levels of microwave radiation

    International Nuclear Information System (INIS)

    Phelan, A.M.; Neubauer, C.F.; Timm, R.; Neirenberg, J.; Lange, D.G.

    1994-01-01

    Sprague-Dawley rats (200-250 g) were exposed 30 min/day for 4 days to thermogenic levels (rectal temperature increase of 2.2 degrees C) of microwave radiation [2.45 GHz, 80 mW/cm 2 , continuous-wave mode (CW)] or to a radiant heat source resulting in an equivalent increase in body temperature of 2.2 degrees C. On the fifth day the animals were sacrificed and their livers removed. The canalicular membranes were isolated and evaluated for adenosinetriphosphatase (ATPase) activity, total fatty acid composition and membrane fluidity characteristics. Mg ++ -ATPase activity (V max ) decreased by 48.5% in the group exposed to microwave radiation, with no significant change in the group exposed to radiant heat. The decrease in Mg ++ -ATPase was partially compensated by a concomitant increase in Na + /K + -ATPase activity (170% increase in V max over control) in animals exposed to microwave radiation, while no change occurred in the group exposed to radiant heat. This alteration in ATPase activity in the group exposed to microwave radiation is associated with a large decrease in the ratio of saturated to unsaturated fatty acids. Conversely, the group exposed to radiant heat had an increase in the ratio of saturated to unsaturated fatty acids. The most dramatic changes were found in the levels of arachidonic acid. Finally, the electron paramagnetic resonance (EPR) spin label technique used to measure the fluidity of the canalicular membranes of the animals in the three groups (sham, microwave radiation and radiant heat) indicated that the results were different in the three groups, reflecting the changes found in their fatty acid composition. The physiological response to open-quotes equivalentclose quotes thermal loads in rats is expressed differently for different types of energy sources. Possible mechanisms producing these divergent thermogenic responses are discussed. 34 refs., 3 figs., 2 tabs

  5. Shoestring Budget Radio Astronomy (Abstract)

    Science.gov (United States)

    Hoot, J. E.

    2017-12-01

    (Abstract only) The commercial exploitation of microwave frequencies for cellular, WiFi, Bluetooth, HDTV, and satellite digital media transmission has brought down the cost of the components required to build an effective radio telescope to the point where, for the cost of a good eyepiece, you can construct and operate a radio telescope. This paper sets forth a family of designs for 1421 MHz telescopes. It also proposes a method by which operators of such instruments can aggregate and archive data via the Internet. With 90 or so instruments it will be possible to survey the entire radio sky for transients with a 24 hour cadence.

  6. The Liverpool Microwave Palaeointensity System

    Science.gov (United States)

    Hill, Mimi; Biggin, Andrew; Hawkins, Louise; Hodgson, Emma; Hurst, Elliot

    2016-04-01

    The motivation for the group at Liverpool in the 1990s (led by John Shaw and Derek Walton) to start experimenting with using microwaves to demagnetise and remagnetise palaeomagnetic samples, rather than heating using conventional ovens, was to reduce laboratory induced alteration in absolute palaeointensity experiments. As with other methods, the non-ideal effects of grain size and naturally altered remanence must still be addressed. From humble beginnings using a domestic microwave oven the current 4th generation microwave system (MWS) has developed in to an integrated combined 14 GHz microwave resonant cavity and SQUID magnetometer system. The MWS is designed to investigate one 5 mm diameter sample at a time with microwave exposure (the equivalent of a heating step in conventional experiments) ranging from a few seconds up to around a minute. Each experiment (protocol, checks, direction and strength of applied field, number of steps etc) can be tailored to the behaviour of each individual sample. There have been many published studies demonstrating the equivalence of conventional thermal (Thellier) and microwave techniques using both artificial and natural remanence and also that the microwave method can indeed reduce laboratory induced alteration. Here an overview of the present MWS including a discussion of the physical processes occurring will be given. Examples of current projects (both archaeological and geological) utilising the method will also be described. Finally, future developments and applications of the method will be discussed.

  7. Microwave-induced combustion synthesis and electrical conductivity of Ce1-xGd xO2-1/2x ceramics

    International Nuclear Information System (INIS)

    Fu, Y.-P.; Chang, Y.-S.; Wen, S.-B.

    2006-01-01

    Ce 1-x Gd x O 2-1/2x nanopowder were successfully synthesized by microwave-induced combustion process. For the preparation, cerium nitrate, gadolinium nitrate hexahydrate, and urea were used for the microwave-induced combustion process. The process took only 30 min to obtain Ce 1-x Gd x O 2-1/2x powders. The exo-endo temperature, phase identification, and morphology of resultant powders were investigated by TG/DTA, XRD, and SEM. The as-received Ce 1-x Gd x O 2-1/2x powders showed that the average particle size ranged from 18 to 50 nm, crystallite dimension varied from 11 to 20 nm, and the specific surface area was distribution from 16 to 46 m 2 /g. As for Ce 1-x Gd x O 2-1/2x ceramics sintered at 1450 deg. C for 3 h, the bulk density of Ce 1-x Gd x O 2-1/2x ceramics were over 91% of the theoretical density, the maximum electrical conductivity, σ 700deg.C = 0.017 S/cm with minimum activation energy, E a = 0.869 eV was found at Ce 0.80 Gd 0.20 O 1.90 ceramic

  8. Abstracts and Abstracting in Knowledge Discovery.

    Science.gov (United States)

    Pinto, Maria; Lancaster, F. W.

    1999-01-01

    Presents various levels of criteria for judging the quality of abstracts and abstracting. Requirements for abstracts to be read by humans are compared with requirements for those to be searched by computer. Concludes that the wide availability of complete text in electronic form does not reduce the value of abstracts for information retrieval.…

  9. Thermal Ablation of Colorectal Lung Metastases: Retrospective Comparison Among Laser-Induced Thermotherapy, Radiofrequency Ablation, and Microwave Ablation.

    Science.gov (United States)

    Vogl, Thomas J; Eckert, Romina; Naguib, Nagy N N; Beeres, Martin; Gruber-Rouh, Tatjana; Nour-Eldin, Nour-Eldin A

    2016-12-01

    The purpose of this study is to retrospectively evaluate local tumor control, time to tumor progression, and survival rates among patients with lung metastatic colorectal cancer who have undergone ablation therapy performed using laser-induced thermotherapy (LITT), radiofrequency ablation (RFA), or microwave ablation (MWA). Data for this retrospective study were collected from 231 CT-guided ablation sessions performed for 109 patients (71 men and 38 women; mean [± SD] age, 68.6 ± 11.2 years; range, 34-94 years) from May 2000 to May 2014. Twenty-one patients underwent LITT (31 ablations), 41 patients underwent RFA (75 ablations), and 47 patients underwent MWA (125 ablations). CT scans were acquired 24 hours after each therapy session and at follow-up visits occurring at 3, 6, 12, 18, and 24 months after ablation. Survival rates were calculated from the time of the first ablation session, with the use of Kaplan-Meier and log-rank tests. Changes in the volume of the ablated lesions were measured using the Kruskal-Wallis method. Local tumor control was achieved in 17 of 25 lesions (68.0%) treated with LITT, 45 of 65 lesions (69.2%) treated with RFA, and 91 of 103 lesions (88.3%) treated with MWA. Statistically significant differences were noted when MWA was compared with LITT at 18 months after ablation (p = 0.01) and when MWA was compared with RFA at 6 months (p = 0.004) and 18 months (p = 0.01) after ablation. The overall median time to local tumor progression was 7.6 months. The median time to local tumor progression was 10.4 months for lesions treated with LITT, 7.2 months for lesions treated with RFA, and 7.5 months for lesions treated with MWA, with no statistically significant difference noted. New pulmonary metastases developed in 47.6% of patients treated with LITT, in 51.2% of patients treated with RFA, and in 53.2% of patients treated with MWA. According to the Kaplan-Meier test, median survival was 22.1 months for patients who underwent LITT, 24.2 months

  10. Microwave Irradiation

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 3. Microwave Irradiation - Way to Eco-friendly, Green Chemistry. Rashmi Sanghi. General Article Volume 5 Issue 3 March 2000 pp 77-81. Fulltext. Click here to view fulltext PDF. Permanent link:

  11. Construction and surface/interface behavior of bio-functional surface layer by microwave-excited Ar/H2O plasma-induced polyethylene glycol polymerization

    Science.gov (United States)

    Shao, Z.; Ogino, A.; Nagatsu, M.

    2017-07-01

    Ar/H2O microwave-excited surface-wave plasma-induced grafting-polymerization and crosslinking technique was presented to construct a bio-functional surface layer. Optical emission spectroscopy was used to diagnose Ar/H2O plasma. The surface/interface behavior especially the aging effect of hydroxyl groups over the grafted PEG spacer layer was investigated by measuring water contact angle and X-ray photoelectron spectroscopy. The results demonstrate that the addition of water vapor into Ar plasma can optimize the concentration of hydroxyl functional groups on surface; grafted PEG spacer layer can provide a long-term hydrophilicity of PU films, and alleviate the aging effect of hydroxyl functional groups.

  12. Microwave-induced zero-resistance state in two-dimensional electron systems with unidirectional periodic modulation

    Energy Technology Data Exchange (ETDEWEB)

    Bykov, A. A.; Rodyakina, E. E.; Latyshev, A. V. [Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Strygin, I. S.; Goran, A. V.; Kalagin, A. K. [Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090 (Russian Federation)

    2016-01-04

    In this study we fabricated lateral superlattices (LSLs) based on the selectively doped GaAs/AlAs heterostructures with a high-mobility two-dimensional (2D) electron gas. The LSLs were formed using the electron-beam lithography and lift-off techniques, which produced a set of metallic strips on top of a heterojunction. The amplitude of the 2D electron gas modulation in the LSL was controlled by the gate voltage applied to the metallic strips. The LSLs with two different periods (a = 200 nm and 500 nm) were used to investigate the influence of microwave radiation with the frequency of 110–150 GHz on the 2D electron transport at the temperature T = 1.6 K in the magnetic field B < 1 T. We have found that zero-resistance states (ZRSs) appear under the microwave radiation in the 2D systems with a unidirectional periodic modulation. These ZRSs are located at the minima of commensurability oscillations.

  13. Simultaneous determination of bromine and iodine in milk powder for adult and infant nutrition by plasma based techniques after digestion using microwave-induced combustion

    International Nuclear Information System (INIS)

    Picoloto, Rochele S.; Doneda, Morgana; Flores, Eder L.M.; Mesko, Marcia F.; Flores, Erico M.M.; Mello, Paola A.

    2015-01-01

    In this work, bromine and iodine determination in milk powder for adult and infant nutrition was performed by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) after digestion by microwave-induced combustion (MIC). Contrarily to previous works using MIC, a higher sample mass was digested (700 mg). Water and ammonium hydroxide (10 to 100 mmol L −1 ) were investigated as absorbing solutions and accurate results were achieved using a 25 mmol L −1 NH 4 OH solution. Moreover, the high stability of analytes after digestion (up to 30 days) using this solution was observed. The accuracy of the proposed MIC method was evaluated using certified and reference materials of milk powder (NIST 1549 and NIST 8435). No statistical difference was observed between results obtained by MIC-ICP-MS and reference values. Results for samples were also compared with those obtained by ICP-OES and no statistical difference was observed. Microwave-assisted alkaline extraction (MW-AE) was also evaluated for milk powder using NH 4 OH and tetramethylammonium hydroxide solutions. Solutions obtained after digestion by MIC (whole milk powder) presented low carbon content in digests (< 25 mg L −1 ) while solutions obtained after alkaline extraction presented up to 10,000 mg L −1 of C. MIC method was preferable in view of the possibility of obtaining solutions with low carbon content even using a relatively high sample mass (up to 700 mg) avoiding additional dilution prior to ICP-MS analysis, thus allowing better detection limits. Limits of detection obtained by MIC-ICP-MS were 0.007 and 0.003 μg g −1 for Br and I, respectively, while for MW-AE were 0.1 and 0.05 μg g −1 respectively for Br and I. Among the main advantages of the proposed method are the use of diluted alkaline solutions that is in agreement with green analytical chemistry recommendations, the high stability of analytes in solution and the

  14. From Abstract Art to Abstracted Artists

    Directory of Open Access Journals (Sweden)

    Romi Mikulinsky

    2016-11-01

    Full Text Available What lineage connects early abstract films and machine-generated YouTube videos? Hans Richter’s famous piece Rhythmus 21 is considered to be the first abstract film in the experimental tradition. The Webdriver Torso YouTube channel is composed of hundreds of thousands of machine-generated test patterns designed to check frequency signals on YouTube. This article discusses geometric abstraction vis-à-vis new vision, conceptual art and algorithmic art. It argues that the Webdriver Torso is an artistic marvel indicative of a form we call mathematical abstraction, which is art performed by computers and, quite possibly, for computers.

  15. Effects of ionic conduction on hydrothermal hydrolysis of corn starch and crystalline cellulose induced by microwave irradiation.

    Science.gov (United States)

    Tsubaki, Shuntaro; Oono, Kiriyo; Onda, Ayumu; Yanagisawa, Kazumichi; Mitani, Tomohiko; Azuma, Jun-Ichi

    2016-02-10

    This study investigated the effects of ionic conduction of electrolytes under microwave field to facilitate hydrothermal hydrolysis of corn starch and crystalline cellulose (Avicel), typical model biomass substrates. Addition of 0.1M NaCl was effective to improve reducing sugar yield by 1.61-fold at unit energy (kJ) level. Although Avicel cellulose was highly recalcitrant to hydrothermal hydrolysis, addition of 0.1M MgCl2 improved reducing sugar yield by 6.94-fold at unit energy (kJ). Dielectric measurement of the mixture of corn starch/water/electrolyte revealed that ionic conduction of electrolytes were strongly involved in facilitating hydrothermal hydrolysis of polysaccharides. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Microwave power engineering applications

    CERN Document Server

    Okress, Ernest C

    2013-01-01

    Microwave Power Engineering, Volume 2: Applications introduces the electronics technology of microwave power and its applications. This technology emphasizes microwave electronics for direct power utilization and transmission purposes. This volume presents the accomplishments with respect to components, systems, and applications and their prevailing limitations in the light of knowledge of the microwave power technology. The applications discussed include the microwave heating and other processes of materials, which utilize the magnetron predominantly. Other applications include microwave ioni

  17. Advances in microwaves 8

    CERN Document Server

    Young, Leo

    2013-01-01

    Advances in Microwaves, Volume 8 covers the developments in the study of microwaves. The book discusses the circuit forms for microwave integrated circuits; the analysis of microstrip transmission lines; and the use of lumped elements in microwave integrated circuits. The text also describes the microwave properties of ferrimagnetic materials, as well as their interaction with electromagnetic waves propagating in bounded waveguiding structures. The integration techniques useful at high frequencies; material technology for microwave integrated circuits; specific requirements on technology for d

  18. Programme and abstracts

    International Nuclear Information System (INIS)

    1975-01-01

    Abstracts of 25 papers presented at the congress are given. The abstracts cover various topics including radiotherapy, radiopharmaceuticals, radioimmunoassay, health physics, radiation protection and nuclear medicine

  19. 2.45-GHz microwave irradiation adversely affects reproductive function in male mouse, Mus musculus by inducing oxidative and nitrosative stress.

    Science.gov (United States)

    Shahin, S; Mishra, V; Singh, S P; Chaturvedi, C M

    2014-05-01

    Electromagnetic radiations are reported to produce long-term and short-term biological effects, which are of great concern to human health due to increasing use of devices emitting EMR especially microwave (MW) radiation in our daily life. In view of the unavoidable use of MW emitting devices (microwaves oven, mobile phones, Wi-Fi, etc.) and their harmful effects on biological system, it was thought worthwhile to investigate the long-term effects of low-level MW irradiation on the reproductive function of male Swiss strain mice and its mechanism of action. Twelve-week-old mice were exposed to non-thermal low-level 2.45-GHz MW radiation (CW for 2 h/day for 30 days, power density = 0.029812 mW/cm(2) and SAR = 0.018 W/Kg). Sperm count and sperm viability test were done as well as vital organs were processed to study different stress parameters. Plasma was used for testosterone and testis for 3β HSD assay. Immunohistochemistry of 3β HSD and nitric oxide synthase (i-NOS) was also performed in testis. We observed that MW irradiation induced a significant decrease in sperm count and sperm viability along with the decrease in seminiferous tubule diameter and degeneration of seminiferous tubules. Reduction in testicular 3β HSD activity and plasma testosterone levels was also noted in the exposed group of mice. Increased expression of testicular i-NOS was observed in the MW-irradiated group of mice. Further, these adverse reproductive effects suggest that chronic exposure to nonionizing MW radiation may lead to infertility via free radical species-mediated pathway.

  20. [Application of microwave irradiation technology to the field of pharmaceutics].

    Science.gov (United States)

    Zhang, Xue-Bing; Shi, Nian-Qiu; Yang, Zhi-Qiang; Wang, Xing-Lin

    2014-03-01

    Microwaves can be directly transformed into heat inside materials because of their ability of penetrating into any substance. The degree that materials are heated depends on their dielectric properties. Materials with high dielectric loss are more easily to reach a resonant state by microwaves field, then microwaves can be absorbed efficiently. Microwave irradiation technique with the unique heating mechanisms could induce drug-polymer interaction and change the properties of dissolution. Many benefits such as improving product quality, increasing energy efficiency and reducing times can be obtained by microwaves. This paper summarized characteristics of the microwave irradiation technique, new preparation techniques and formulation process in pharmaceutical industry by microwave irradiation technology. The microwave technology provides a new clue for heating and drying in the field of pharmaceutics.

  1. Heterogeneously Integrated Microwave Signal Generators with Narrow Linewidth Lasers

    Science.gov (United States)

    2017-03-20

    key benefit of heterogeneous silicon photonics for this application is the ability to control the confinement factor by changing the width of...Abstract: We explore photonic microwave signal generation utilizing the heterogeneous silicon -III/V platform and the benefits and execution of a fully...Semiconductor lasers; Tunable lasers; Silicon photonics; Millimeter-wave Introduction Frequency agile microwave and millimeter wave microwave sources at

  2. Simultaneous determination of bromine and iodine in milk powder for adult and infant nutrition by plasma based techniques after digestion using microwave-induced combustion

    Energy Technology Data Exchange (ETDEWEB)

    Picoloto, Rochele S. [Núcleo de Química, Universidade Tecnológica Federal do Paraná, 85884-000 Medianeira, PR (Brazil); Doneda, Morgana [Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil); Flores, Eder L.M. [Núcleo de Química, Universidade Tecnológica Federal do Paraná, 85884-000 Medianeira, PR (Brazil); Mesko, Marcia F. [Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, 96010-610 Pelotas, RS (Brazil); Flores, Erico M.M. [Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil); Mello, Paola A., E-mail: paola.mello@ufsm.br [Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil)

    2015-05-01

    In this work, bromine and iodine determination in milk powder for adult and infant nutrition was performed by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) after digestion by microwave-induced combustion (MIC). Contrarily to previous works using MIC, a higher sample mass was digested (700 mg). Water and ammonium hydroxide (10 to 100 mmol L{sup −1}) were investigated as absorbing solutions and accurate results were achieved using a 25 mmol L{sup −1} NH{sub 4}OH solution. Moreover, the high stability of analytes after digestion (up to 30 days) using this solution was observed. The accuracy of the proposed MIC method was evaluated using certified and reference materials of milk powder (NIST 1549 and NIST 8435). No statistical difference was observed between results obtained by MIC-ICP-MS and reference values. Results for samples were also compared with those obtained by ICP-OES and no statistical difference was observed. Microwave-assisted alkaline extraction (MW-AE) was also evaluated for milk powder using NH{sub 4}OH and tetramethylammonium hydroxide solutions. Solutions obtained after digestion by MIC (whole milk powder) presented low carbon content in digests (< 25 mg L{sup −1}) while solutions obtained after alkaline extraction presented up to 10,000 mg L{sup −1} of C. MIC method was preferable in view of the possibility of obtaining solutions with low carbon content even using a relatively high sample mass (up to 700 mg) avoiding additional dilution prior to ICP-MS analysis, thus allowing better detection limits. Limits of detection obtained by MIC-ICP-MS were 0.007 and 0.003 μg g{sup −1} for Br and I, respectively, while for MW-AE were 0.1 and 0.05 μg g{sup −1} respectively for Br and I. Among the main advantages of the proposed method are the use of diluted alkaline solutions that is in agreement with green analytical chemistry recommendations, the high stability of

  3. Practical microwave electron devices

    CERN Document Server

    Meurant, Gerard

    2013-01-01

    Practical Microwave Electron Devices provides an understanding of microwave electron devices and their applications. All areas of microwave electron devices are covered. These include microwave solid-state devices, including popular microwave transistors and both passive and active diodes; quantum electron devices; thermionic devices (including relativistic thermionic devices); and ferrimagnetic electron devices. The design of each of these devices is discussed as well as their applications, including oscillation, amplification, switching, modulation, demodulation, and parametric interactions.

  4. Microwave-Assisted Rapid Enzymatic Synthesis of Nucleic Acids.

    Science.gov (United States)

    Hari Das, Rakha; Ahirwar, Rajesh; Kumar, Saroj; Nahar, Pradip

    2016-07-02

    Herein we report microwave-induced enhancement of the reactions catalyzed by Escherichia coli DNA polymerase I and avian myeloblastosis virus-reverse transcriptase. The reactions induced by microwaves result in a highly selective synthesis of nucleic acids in 10-50 seconds. In contrast, same reactions failed to give desired reaction products when carried out in the same time periods, but without microwave irradiation. Each of the reactions was carried out for different duration of microwave exposure time to find the optimum reaction time. The products produced by the respective enzyme upon microwave irradiation of the reaction mixtures were identical to that produced by the conventional procedures. As the microwave-assisted reactions are rapid, microwave could be a useful alternative to the conventional and time consuming procedures of enzymatic synthesis of nucleic acids.

  5. Program and abstracts

    International Nuclear Information System (INIS)

    1975-01-01

    Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled:Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Physics Education; SANCGASS; Astronomy; Plasma Physics; Physics in Industry; Applied and General Physics

  6. Determination of methylmercury in fish tissue by gas chromatography with microwave-induced plasma atomic emission spectrometry after derivatization with sodium tetraphenylborate.

    Science.gov (United States)

    Palmieri, H E; Leonel, L V

    2000-03-01

    The detection of methylmercury species (MeHg) in fish tissue was investigated. Samples were digested with KOH-methanol and acidified prior to extraction with methylene chloride. MeHg was back-extracted from the organic phase into water. An aliquot of this aqueous solution (buffered to pH 5) was subjected to derivatization with sodium tetraphenylborate (NaBPh4) and then extracted with toluene. The organic phase containing MePhHg was injected into a gas chromatograph (GC) which is on-line with a microwave-induced plasma atomic emission spectrometer (MIP-AED). The quantification limit was about 0.6 microg/g and 0.1 microg/g of MeHg (as Hg) for 0.08 g of freeze-dried fish powder and 0.5 g of fresh samples, respectively. Two certified reference materials, CRM 464 (tuna fish) from Community Bureau of Reference-BCR and DORM-2 (dogfish muscle) from National Research Council Canada-NRC were selected for checking the accuracy of the method. This methodology was applied to the determination of MeHg in some kinds of fish from the Carmo river with alluvial gold recovery activities ("garimpos") in Mariana, Minas Gerais, Brazil.

  7. Microwave-Assisted Synthesis of Imidazo[4,5-f][1,10]phenanthroline Derivatives as Apoptosis Inducers in Chemotherapy by Stabilizing Bcl-2 G-quadruplex DNA

    Directory of Open Access Journals (Sweden)

    Li Li

    2017-05-01

    Full Text Available Herein, a series of imidazo[4,5-f][1,10] phenanthroline derivatives RPIP (PIP = imidazo [4,5-f][1,10] phenanthroline, R = NO2, 1; CF3, 2; Cl, 3; OH, 4 have been synthesized in yields of 82.3–94.7% at 100 °C under the irradiation of microwave. MTT assay has been utilized to evaluate the inhibitory activity (IC50 of these compounds against the growth of various tumor cells, and the results revealed that these compounds, especially 1, exhibited excellent inhibitory activity against the growth of A549 cells with IC50 of 15.03 μM. Moreover, it’s also confirmed that 1 can penetrate into the membrane of tumor cells and distribute in mitochondria when observed under microscopy, resulting apoptosis of tumor cells. The further studies showed that 1 can bind to bcl-2 G-quadruplex DNA, which demonstrated by the increase of melting point of bcl-2 G4 DNA in the presence of 1, as well as electronic titration and emission spectra. In a word, this kind of compound may develop as a potential apoptosis inducer in cancer chemotherapy via binding and stabilizing to the bcl-2 G-quadruplex DNA.

  8. Satellite passive microwaves for monitoring deforestation and drought-induced carbon losses in sub-Saharan Africa

    Science.gov (United States)

    Brandt, M.; Wigneron, J. P.; Chave, J.; Tagesson, T.; Penuelas, J.; Ciais, P.; Rasmussen, K.; Tian, F.; Mbow, C.; Al-Yaari, A.; Rodriguez-Fernandez, N.; Zhang, W.; Kerr, Y. H.; Tucker, C. J.; Mialon, A.; Verger, A.; Fensholt, R.

    2017-12-01

    The African continent is facing one of the driest periods in the past three decades and continuing deforestation. These disturbances threaten vegetation carbon (C) stocks and highlight the need for an operational tool for monitoring carbon stock dynamics. Knowledge of the amount, distribution, and turnover of carbon in African vegetation is crucial for understanding the effects of human pressure and climate change, but the shortcomings of optical and radar satellite products and the lack of systematic field inventories have led to considerable uncertainty in documenting patterns and dynamics of carbon stocks, in particular for drylands. Static carbon maps have been developed, but the temporal dynamics of carbon stocks cannot be derived from the benchmark maps, impeding timely, repeated, and reliable carbon assessments. The Soil Moisture and Ocean Salinity (SMOS) mission launched in 2009 was the first passive microwave-based satellite system operating at L-band (1.4 GHz) frequency. The low frequencies allow the satellite to sense deep within the canopy layer with less influence by the green non-woody plant components. The vegetation optical depth (VOD) derived from SMOS, henceforth L-VOD, is thus less sensitive to saturation effects, marking an important step forward in the monitoring of carbon as a natural resource. In this study, we apply for the first time L-VOD to quantify the inter-annual dynamics of aboveground carbon stocks for the period 2010-2016. We use this new technique to document patterns of carbon gains and losses in sub-Saharan Africa with a focus of dryland response to recent dry years. Results show that drylands lost carbon at a rate of -0.06 Pg C y-1 associated with drying trends, while humid areas lost only -0.02 Pg C y-1. These trends reflect a high inter-annual variability with a very wet (2011) and a very dry year (2016) associated with carbon gains and losses respectively. This study demonstrates, first, the operational applicability of L

  9. Simultaneous determination of bromine and iodine in milk powder for adult and infant nutrition by plasma based techniques after digestion using microwave-induced combustion

    Science.gov (United States)

    Picoloto, Rochele S.; Doneda, Morgana; Flores, Eder L. M.; Mesko, Marcia F.; Flores, Erico M. M.; Mello, Paola A.

    2015-05-01

    In this work, bromine and iodine determination in milk powder for adult and infant nutrition was performed by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) after digestion by microwave-induced combustion (MIC). Contrarily to previous works using MIC, a higher sample mass was digested (700 mg). Water and ammonium hydroxide (10 to 100 mmol L- 1) were investigated as absorbing solutions and accurate results were achieved using a 25 mmol L- 1 NH4OH solution. Moreover, the high stability of analytes after digestion (up to 30 days) using this solution was observed. The accuracy of the proposed MIC method was evaluated using certified and reference materials of milk powder (NIST 1549 and NIST 8435). No statistical difference was observed between results obtained by MIC-ICP-MS and reference values. Results for samples were also compared with those obtained by ICP-OES and no statistical difference was observed. Microwave-assisted alkaline extraction (MW-AE) was also evaluated for milk powder using NH4OH and tetramethylammonium hydroxide solutions. Solutions obtained after digestion by MIC (whole milk powder) presented low carbon content in digests (alkaline extraction presented up to 10,000 mg L- 1 of C. MIC method was preferable in view of the possibility of obtaining solutions with low carbon content even using a relatively high sample mass (up to 700 mg) avoiding additional dilution prior to ICP-MS analysis, thus allowing better detection limits. Limits of detection obtained by MIC-ICP-MS were 0.007 and 0.003 μg g- 1 for Br and I, respectively, while for MW-AE were 0.1 and 0.05 μg g- 1 respectively for Br and I. Among the main advantages of the proposed method are the use of diluted alkaline solutions that is in agreement with green analytical chemistry recommendations, the high stability of analytes in solution and the suitability of digests for analysis by ICP-MS and also ICP

  10. Deprotection of oximes using urea nitrate under microwave irradiation

    Indian Academy of Sciences (India)

    Abstract. A new mild and efficient method for the cleavage of oximes to carbonyl compounds using readily available urea nitrate in acetonitrile-water (95 : 5), under microwave irradiation within 2 min, in good yields is reported.

  11. Microwave heating type evaporator

    International Nuclear Information System (INIS)

    Taura, Masazumi; Nishi, Akio; Morimoto, Takashi; Izumi, Jun; Tamura, Kazuo; Morooka, Akihiko.

    1987-01-01

    Purpose: To prevent evaporization stills against corrosion due to radioactive liquid wastes. Constitution: Microwaves are supplied from a microwave generator by way of a wave guide tube and through a microwave permeation window to the inside of an evaporatization still. A matching device is attached to the wave guide tube for transmitting the microwaves in order to match the impedance. When the microwaves are supplied to the inside of the evaporization still, radioactive liquid wastes supplied from a liquid feed port by way of a spray tower to the inside of the evaporization still is heated and evaporated by the induction heating of the microwaves. (Seki, T.)

  12. Compilation of Theses Abstracts

    National Research Council Canada - National Science Library

    2005-01-01

    This publication contains unclassified/unrestricted abstracts of classified or restricted theses submitted for the degrees of Doctor of Philosophy, Master of Business Administration, Master of Science...

  13. Computational Abstraction Steps

    DEFF Research Database (Denmark)

    Thomsen, Lone Leth; Thomsen, Bent; Nørmark, Kurt

    2010-01-01

    and class instantiations. Our teaching experience shows that many novice programmers find it difficult to write programs with abstractions that materialise to concrete objects later in the development process. The contribution of this paper is the idea of initiating a programming process by creating......In this paper we discuss computational abstraction steps as a way to create class abstractions from concrete objects, and from examples. Computational abstraction steps are regarded as symmetric counterparts to computational concretisation steps, which are well-known in terms of function calls...

  14. Nuclear medicine. Abstracts; Nuklearmedizin 2000. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2000-07-01

    This issue of the journal contains the abstracts of the 183 conference papers as well as 266 posters presented at the conference. Subject fields covered are: Neurology, psychology, oncology, pediatrics, radiopharmacy, endocrinology, EDP, measuring equipment and methods, radiological protection, cardiology, and therapy. (orig./CB) [German] Die vorliegende Zeitschrift enthaelt die Kurzfassungen der 183 auf der Tagung gehaltenen Vortraege sowie der 226 praesentierten Poster, die sich mit den folgenden Themen befassten: Neurologie, Psychiatrie, Onkologie, Paediatrie, Radiopharmazie, Endokrinologie, EDV, Messtechnik, Strahlenschutz, Kardiologie sowie Therapie. (MG)

  15. Application of high power microwave vacuum electron devices

    International Nuclear Information System (INIS)

    Ding Yaogen; Liu Pukun; Zhang Zhaochuan; Wang Yong; Shen Bin

    2011-01-01

    High power microwave vacuum electron devices can work at high frequency, high peak and average power. They have been widely used in military and civil microwave electron systems, such as radar, communication,countermeasure, TV broadcast, particle accelerators, plasma heating devices of fusion, microwave sensing and microwave heating. In scientific research, high power microwave vacuum electron devices are used mainly on high energy particle accelerator and fusion research. The devices include high peak power klystron, CW and long pulse high power klystron, multi-beam klystron,and high power gyrotron. In national economy, high power microwave vacuum electron devices are used mainly on weather and navigation radar, medical and radiation accelerator, TV broadcast and communication system. The devices include high power pulse and CW klystron, extended interaction klystron, traveling wave tube (TWT), magnetron and induced output tube (IOT). The state of art, common technology problems and trends of high power microwave vacuum electron devices are introduced in this paper. (authors)

  16. Scientific program and abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Gerich, C. (ed.)

    1983-01-01

    The Fifth International Conference on High-Power Particle Beams is organized jointly by the Lawrence Livermore National Laboratory and Physics International Company. As in the previous conferences in this series, the program includes the following topics: high-power, electron- and ion-beam acceleration and transport; diode physics; high-power particle beam interaction with plasmas and dense targets; particle beam fusion (inertial confinement); collective ion acceleration; particle beam heating of magnetically confined plasmas; and generation of microwave/free-electron lasers.

  17. Scientific program and abstracts

    International Nuclear Information System (INIS)

    Gerich, C.

    1983-01-01

    The Fifth International Conference on High-Power Particle Beams is organized jointly by the Lawrence Livermore National Laboratory and Physics International Company. As in the previous conferences in this series, the program includes the following topics: high-power, electron- and ion-beam acceleration and transport; diode physics; high-power particle beam interaction with plasmas and dense targets; particle beam fusion (inertial confinement); collective ion acceleration; particle beam heating of magnetically confined plasmas; and generation of microwave/free-electron lasers

  18. Neighbourhood Abstraction in GROOVE

    NARCIS (Netherlands)

    Rensink, Arend; Zambon, Eduardo; De Lara, J.; Varro, D.

    2011-01-01

    Important classes of graph grammars have infinite state spaces and therefore cannot be verified with traditional model checking techniques. One way to address this problem is to perform graph abstraction, which allows us to generate a finite abstract state space that over-approximates the original

  19. Truthful Monadic Abstractions

    DEFF Research Database (Denmark)

    Brock-Nannestad, Taus; Schürmann, Carsten

    2012-01-01

    indefinitely, finding neither a proof nor a disproof of a given subgoal. In this paper we characterize a family of truth-preserving abstractions from intuitionistic first-order logic to the monadic fragment of classical first-order logic. Because they are truthful, these abstractions can be used to disprove...

  20. Check Sample Abstracts.

    Science.gov (United States)

    Alter, David; Grenache, David G; Bosler, David S; Karcher, Raymond E; Nichols, James; Rajadhyaksha, Aparna; Camelo-Piragua, Sandra; Rauch, Carol; Huddleston, Brent J; Frank, Elizabeth L; Sluss, Patrick M; Lewandrowski, Kent; Eichhorn, John H; Hall, Janet E; Rahman, Saud S; McPherson, Richard A; Kiechle, Frederick L; Hammett-Stabler, Catherine; Pierce, Kristin A; Kloehn, Erica A; Thomas, Patricia A; Walts, Ann E; Madan, Rashna; Schlesinger, Kathie; Nawgiri, Ranjana; Bhutani, Manoop; Kanber, Yonca; Abati, Andrea; Atkins, Kristen A; Farrar, Robert; Gopez, Evelyn Valencerina; Jhala, Darshana; Griffin, Sonya; Jhala, Khushboo; Jhala, Nirag; Bentz, Joel S; Emerson, Lyska; Chadwick, Barbara E; Barroeta, Julieta E; Baloch, Zubair W; Collins, Brian T; Middleton, Owen L; Davis, Gregory G; Haden-Pinneri, Kathryn; Chu, Albert Y; Keylock, Joren B; Ramoso, Robert; Thoene, Cynthia A; Stewart, Donna; Pierce, Arand; Barry, Michelle; Aljinovic, Nika; Gardner, David L; Barry, Michelle; Shields, Lisa B E; Arnold, Jack; Stewart, Donna; Martin, Erica L; Rakow, Rex J; Paddock, Christopher; Zaki, Sherif R; Prahlow, Joseph A; Stewart, Donna; Shields, Lisa B E; Rolf, Cristin M; Falzon, Andrew L; Hudacki, Rachel; Mazzella, Fermina M; Bethel, Melissa; Zarrin-Khameh, Neda; Gresik, M Vicky; Gill, Ryan; Karlon, William; Etzell, Joan; Deftos, Michael; Karlon, William J; Etzell, Joan E; Wang, Endi; Lu, Chuanyi M; Manion, Elizabeth; Rosenthal, Nancy; Wang, Endi; Lu, Chuanyi M; Tang, Patrick; Petric, Martin; Schade, Andrew E; Hall, Geraldine S; Oethinger, Margret; Hall, Geraldine; Picton, Avis R; Hoang, Linda; Imperial, Miguel Ranoa; Kibsey, Pamela; Waites, Ken; Duffy, Lynn; Hall, Geraldine S; Salangsang, Jo-Anne M; Bravo, Lulette Tricia C; Oethinger, Margaret D; Veras, Emanuela; Silva, Elvia; Vicens, Jimena; Silva, Elvio; Keylock, Joren; Hempel, James; Rushing, Elizabeth; Posligua, Lorena E; Deavers, Michael T; Nash, Jason W; Basturk, Olca; Perle, Mary Ann; Greco, Alba; Lee, Peng; Maru, Dipen; Weydert, Jamie Allen; Stevens, Todd M; Brownlee, Noel A; Kemper, April E; Williams, H James; Oliverio, Brock J; Al-Agha, Osama M; Eskue, Kyle L; Newlands, Shawn D; Eltorky, Mahmoud A; Puri, Puja K; Royer, Michael C; Rush, Walter L; Tavora, Fabio; Galvin, Jeffrey R; Franks, Teri J; Carter, James Elliot; Kahn, Andrea Graciela; Lozada Muñoz, Luis R; Houghton, Dan; Land, Kevin J; Nester, Theresa; Gildea, Jacob; Lefkowitz, Jerry; Lacount, Rachel A; Thompson, Hannis W; Refaai, Majed A; Quillen, Karen; Lopez, Ana Ortega; Goldfinger, Dennis; Muram, Talia; Thompson, Hannis

    2009-02-01

    The following abstracts are compiled from Check Sample exercises published in 2008. These peer-reviewed case studies assist laboratory professionals with continuing medical education and are developed in the areas of clinical chemistry, cytopathology, forensic pathology, hematology, microbiology, surgical pathology, and transfusion medicine. Abstracts for all exercises published in the program will appear annually in AJCP.

  1. Program and abstracts

    International Nuclear Information System (INIS)

    1976-01-01

    Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled: Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Plasma Physics; Solar-Terrestrial Physics; Astrophysics and Astronomy; Radioastronomy; General Physics; Applied Physics; Industrial Physics

  2. Solid waste treatment by microwave irradiation technology

    International Nuclear Information System (INIS)

    Farid Nasir Ani; Arshad Adam Salema

    2010-01-01

    Strict legislative laws both nationally and internationally have enforced the waste management expertise to develop new technologies with regard to waste treatment facilities. This is because the waste is directly linked to human development, technologically, socially and environmentally. In present research work, solid (oil palm biomass and scrap tire) wastes were subjected to microwave irradiation system. Since these wastes are found abundantly locally as well as in surrounding areas of Malaysia. The aim of the present work was to investigate the pyrolysis behavior of oil palm biomass and scrap tires under microwave radiation. Microwave induced fast pyrolysis process was used to produce pyrolysis-oil by mixing waste materials with suitable microwave absorber at different ratio. A modified domestic microwave system with maximum power of 1000 W and 2450 MHz frequency was used. The results showed that the ratio of biomass to microwave absorber plays a significant role on the yield of bio-oil. Temperature profiles revealed the heating characteristics of the waste materials. Generation of heat within the material under microwave is so instantaneous that it takes few seconds to reach high temperature which otherwise is difficult to achieve in conventional systems. Hence, the time and energy consumption of process is significantly reduced by using microwaves irradiation technique. This leads to a lower process cost. Pyrolysis oil from scrap tires showed high heating values. Bio-oil from oil palm biomass showed lower viscosity due to presence of water content and compounds such as phenol, aldehyde and others were detected through FT-IR analysis. Biomass char image analysis showed porous nature when treated with microwave technique however it showed large cracks when treated with conventional electrical furnace. Overall, the results revealed that the waste can be treated efficiently, effectively and environmentally by using new microwave irradiation technique. (author)

  3. Accurate determination of bromine and iodine in medicinal plants by inductively coupled plasma-mass spectrometry after microwave-induced combustion

    Science.gov (United States)

    Nascimento, Mariele S.; Mendes, Ana Luiza G.; Henn, Alessandra S.; Picoloto, Rochele S.; Mello, Paola A.; Flores, Erico M. M.

    2017-12-01

    In this work, a method for the determination of bromine and iodine in medicinal plants by inductively coupled plasma mass spectrometry (ICP-MS) after digestion by microwave-induced combustion (MIC) was developed. Medicinal plants were pressed as pellets and combusted at 20 bar of oxygen. The suitability of absorbing solution (water, 50 mmol L- 1 (NH4)2CO3, 10 mmol L- 1, 25 mmol L- 1, 50 mmol L- 1 or 100 mmol L- 1 NH4OH) was evaluated and a reflux step of 5 min was applied after combustion. The accuracy of the proposed method was evaluated by using certified reference materials (CRMs) of apple leaves and peach leaves and also by spiked samples. Using 50 mmol L- 1 NH4OH as absorbing solution, recoveries close to 100% for bromine and iodine were obtained as well as a low relative standard deviation (5%). No statistical difference (t-test, 95% of confidence level) was observed between the values obtained by ICP-MS after MIC digestion and the certified values. One of the important advantages of the proposed method is that it allowed the use of a relatively high sample mass (1000 mg) of medicinal plant resulting in low limits of quantification (0.033 μg g- 1 and 0.003 μg g- 1 for Br and I, respectively). Blanks were always negligible and only diluted solutions were used, in agreement with current recommendations for analytical methods. A high digestion efficiency was achieved (> 99%) assuring quantitative results. The concentration of analytes in medicinal plants was in the range of 0.17 μg g- 1 to 53.1 μg g- 1 for Br and medicinal plants (125 μg g- 1).

  4. Kinetic, equilibrium and thermodynamic studies of synthetic dye removal using pomegranate peel activated carbon prepared by microwave-induced KOH activation

    Directory of Open Access Journals (Sweden)

    Mohd Azmier Ahmad

    2014-08-01

    Full Text Available Pomegranate peel was converted into activated carbon using microwave induced and KOH activation techniques. The prepared activated carbon (PPAC was characterized using FTIR, TGA, SEM, and nitrogen-adsorption surface area (BET. BET measurements gave remarkable increase in both the surface area (941.02 m2/g and total pore volume (0.470 cm3/g. Various operational parameters such as pH, initial dye concentration, contact time and solution temperature in batch systems were investigated on the use of PPAC in the adsorption of remazol brilliant blue reactive (RBBR dye. At pH 2, the optimum dye removal was 94.36%. The amount of dye removed was dependent on initial dye concentration and solution temperature. Adsorption kinetics was found to follow pseudo-second-order kinetic model. Experimental data were analyzed using eight model equations: Langmuir, Freundlich, Temkin, Dubinin–Radushkevich, Radke Prausnite, Sips, Viet–Sladek and Brouers – Sotolongo isotherms and it was found that the Freundlich isotherm model fitted the adsorption data most with the highest correlation (R2≥0.99 and lowest normalized standard deviation, ∆qe. Both intra-particle and film diffusion governed the adsorption process. Thermodynamic parameters, such as standard Gibbs free energy (∆G0, standard enthalpy (∆H0, standard entropy (∆S0, and the activation energy (Ea were calculated. The adsorption of RBBR dye onto PPAC was found to be spontaneous and exothermic in nature. This study shows that the adsorption follows physisorption mechanism.

  5. Microwave-Assisted Synthesis of Arene Ru(II Complexes Induce Tumor Cell Apoptosis Through Selectively Binding and Stabilizing bcl-2 G-Quadruplex DNA

    Directory of Open Access Journals (Sweden)

    Yanhua Chen

    2016-05-01

    Full Text Available A series of arene Ru(II complexes coordinated with phenanthroimidazole derivatives, [(η6-C6H6Ru(lCl]Cl(1b L = p-ClPIP = 2-(4-Chlorophenylimidazole[4,5f] 1,10-phenanthroline; 2b L = m-ClPIP = 2-(3-Chlorophenylimidazole[4,5f] 1,10-phenanthroline; 3b L = p-NPIP = 2-(4-Nitrophenylimidazole[4,5f] 1,10-phenanthroline; 4b L = m-NPIP = 2-(3-Nitrophenyl imidazole [4,5f] 1,10-phenanthroline were synthesized in yields of 89.9%–92.7% under conditions of microwave irradiation heating for 30 min to liberate four arene Ru(II complexes (1b, 2b, 3b, 4b. The anti-tumor activity of 1b against various tumor cells was evaluated by MTT assay. The results indicated that this complex blocked the growth of human lung adenocarcinoma A549 cells with an IC50 of 16.59 μM. Flow cytometric analysis showed that apoptosis of A549 cells was observed following treatment with 1b. Furthermore, the in vitro DNA-binding behaviors that were confirmed by spectroscopy indicated that 1b could selectively bind and stabilize bcl-2 G-quadruplex DNA to induce apoptosis of A549 cells. Therefore, the synthesized 1b has impressive bcl-2 G-quadruplex DNA-binding and stabilizing activities with potential applications in cancer chemotherapy.

  6. Therapeutic approaches of melatonin in microwave radiations-induced oxidative stress-mediated toxicity on male fertility pattern of Wistar rats.

    Science.gov (United States)

    Meena, Ramovatar; Kumari, Kajal; Kumar, Jitendra; Rajamani, Paulraj; Verma, H N; Kesari, Kavindra Kumar

    2014-06-01

    Microwave (MW) radiation produced by wireless telecommunications and a number of electrical devices used in household or in healthcare institutions may adversely affects the reproductive pattern. Present study aimed to investigate the protective effects of melatonin (is well known antioxidant that protects DNA, lipids and proteins from free radical damage) against oxidative stress-mediated testicular impairment due to long-term exposure of MWs. For this, 70-day-old male Wistar rats were divided into four groups (n = 6/group): Sham exposed, Melatonin (Mel) treated (2 mg/kg), 2.45 GHz MWs exposed and MWs + Mel treated. Exposure took place in Plexiglas cages for 2 h a day for 45 days where, power density (0.21 mW/cm(2)) and specific absorption rate (SAR 0.14 W/Kg) were estimated. After the completion of exposure period, rats were sacrificed and various stress related parameters, that is LDH-X (lactate dehydrogenase isoenzyme) activity, xanthine oxidase (XO), ROS (reactive oxygen species), protein carbonyl content, DNA damage and MDA (malondialdehyde) were performed. Result shows that melatonin prevent oxidative damage biochemically by significant increase (p < 0.001) in the levels of testicular LDH-X, decreased (p < 0.001) levels of MDA and ROS in testis (p < 0.01). Meanwhile, it reversed the effects of MWs on XO, protein carbonyl content, sperm count, testosterone level and DNA fragmentation in testicular cells. These results concluded that the melatonin has strong antioxidative potential against MW induced oxidative stress mediated DNA damage in testicular cells.

  7. Advances in microwaves 7

    CERN Document Server

    Young, Leo

    2013-01-01

    Advances in Microwaves, Volume 7 covers the developments in the study of microwaves. The book discusses the effect of surface roughness on the propagation of the TEM mode, as well as the voltage breakdown of microwave antennas. The text also describes the theory and design considerations of single slotted-waveguide linear arrays and the techniques and theories that led to the achievement of wide bandwidths and ultralow noise temperatures for communication applications. The book will prove invaluable to microwave engineers.

  8. Microwave assisted template synthesis of silver nanoparticles

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Easier, less time consuming, green processes, which yield silver nanoparticles of uniform size, shape and morphology are of interest. Various methods for synthesis, such as conventional temperature as- sisted process, controlled reaction at elevated temperatures, and microwave assisted process have been evalu ...

  9. Particle physics implications of Wilkinson microwave anisotropy ...

    Indian Academy of Sciences (India)

    microwave anisotropy project measurements. U A YAJNIK. Indian Institute of Technology Bombay, Mumbai 400 076, India. E-mail: yajnik@phy.iitb.ac.in. Abstract. We present an overview of the implications of the WMAP data for particle physics. The standard parameter set ϵ, η and ξ characterising the inflaton potential can.

  10. Statistics of the eigenfunctions of microwave cavities

    Indian Academy of Sciences (India)

    Abstract. We study the statistics of the experimental eigenfunctions of chaotic and disordered microwave billiards in terms of the moments of their spatial distributions, such as the inverse partici- pation ratio (IPR) and density-density auto-correlation. A path from chaos to disorder is described in terms of increasing IPR.

  11. Microwave dielectrics: solid solution, ordering and microwave ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 40; Issue 6. Microwave dielectrics: solid solution, ordering and microwave dielectric properties of ( 1 − x ) Ba(Mg 1 / 3 Nb 2 / 3 )O 3 − x Ba(Mg 1 / 8 Nb 3 / 4 )O3 ceramics. YOGITA BISHT RICHA TOMAR PULLANCHIYODAN ABHILASH DEEPA RAJENDRAN LEKSHMI M ...

  12. Microwave processing heats up

    Science.gov (United States)

    Microwaves are a common appliance in many households. In the United States microwave heating is the third most popular domestic heating method food foods. Microwave heating is also a commercial food processing technology that has been applied for cooking, drying, and tempering foods. It's use in ...

  13. GSM 900 MHz Microwave RadiationInduced Alterations of Insulin Level and Histopathological Changes of Liver and Pancreas in Rat

    Directory of Open Access Journals (Sweden)

    Mortazavi S. M. J.

    2016-12-01

    Full Text Available Background: The rapidly increasing use of mobile phones has led to public concerns about possible health effects of these popular communication devices. This study is an attempt to investigate the effects of radiofrequency (RF radiation produced by GSM mobile phones on the insulin release in rats. Methods: Forty two female adult Sprague Dawley rats were randomly divided into 4 groups. Group1 were exposed to RF radiation 6 hours per day for 7 days. Group 2 received sham exposure (6 hours per day for 7 days. Groups 3 and 4 received RF radiation 3 hours per day for 7 days and sham exposure (3 hours per day, respectively. The specific absorption rate (SAR of RF was 2.0W/kg. Results: Our results showed that RF radiations emitted from mobile phone could not alter insulin release in rats. However, mild to severe inflammatory changes in the portal spaces of the liver of rats as well as damage in the cells of islet of Langerhans were observed. These changes were linked with the duration of the exposures. Conclusion: RF exposure can induce inflammatory changes in the liver as well causing damage in the cells of islet of Langerhans.

  14. Rapid biodiesel production using wet microalgae via microwave irradiation

    International Nuclear Information System (INIS)

    Wahidin, Suzana; Idris, Ani; Shaleh, Sitti Raehanah Muhamad

    2014-01-01

    Highlights: • Lipid was directly extracted from wet microalgae using microwave irradiation. • The microwave irradiation and water bath-assisted solvent extraction are applied. • Cell walls are significantly disrupted under microwave irradiation. • Highly disrupted cell walls led to higher biodiesel yield in microwave irradiation. • Microwave irradiation is a promising direct technique with high biodiesel yields. - Abstract: The major challenges for industrial commercialized biodiesel production from microalgae are the high cost of downstream processing such as dewatering and drying, utilization of large volumes of solvent and laborious extraction processes. In order to address these issues the microwave irradiation method was used to produce biodiesel directly from wet microalgae biomass. This alternative method of biodiesel production from wet microalgae biomass is compared with the conventional water bath-assisted solvent extraction. The microwave irradiation extracted more lipids and high biodiesel conversion was obtained compared to the water bath-assisted extraction method due to the high cell disruption achieved and rapid transesterification. The total content of lipid extracted from microwave irradiation and water bath-assisted extraction were 38.31% and 23.01% respectively. The biodiesel produced using microwave irradiation was higher (86.41%) compared to the conventional method. Thus microwave irradiation is an attractive and promising technology to be used in the extraction and transesterification process for efficient biodiesel production

  15. Completeness of Lyapunov Abstraction

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Sloth, Christoffer

    2013-01-01

    the vector field, which allows the generation of a complete abstraction. To compute the functions that define the subdivision of the state space in an algorithm, we formulate a sum of squares optimization problem. This optimization problem finds the best subdivisioning functions, with respect to the ability......This paper addresses the generation of complete abstractions of polynomial dynamical systems by timed automata. For the proposed abstraction, the state space is divided into cells by sublevel sets of functions. We identify a relation between these functions and their directional derivatives along...

  16. Microwave coagulation therapy and drug injection to treat splenic injury.

    Science.gov (United States)

    Zhang, Guoming; Sun, Yuanyuan; Yu, Jie; Dong, Lei; Mu, Nannan; Liu, Xiaohong; Liu, Lanfen; Zhang, Yan; Wang, Xiaofei; Liang, Ping

    2014-01-01

    The present study compares the efficacy of 915- and 2450-MHz contrast-enhanced ultrasound (CEUS)-guided percutaneous microwave coagulation with that of CEUS-guided thrombin injection for the treatment of trauma-induced spleen hemorrhage. In a canine splenic artery hemorrhage model with two levels of arterial diameter (A, microwaves and drug injection. Therapy efficacy was measured by comparing bleeding rate, hemostatic time, bleeding index, bleeding volume, and pathology. The most efficient technique was CEUS-guided 915-MHz percutaneous microwave coagulation therapy in terms of action time and total blood loss. The success rate of the 915-MHz microwave group was higher than that of the 2450-MHz microwave and the drug injection groups (except A level, P microwave group than those in the 2450-MHz microwave and drug injection groups (P microwave group, but pathologic changes of light injury could be seen in the other groups. The present study provides evidence that microwave coagulation therapy is more efficient than thrombin injection for the treatment of splenic hemorrhage. Furthermore, treatment with 915-MHz microwaves stops bleeding more rapidly and generates a wider cauterization zone than does treatment with 2450-MHz microwaves. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Proceedings of microwave processing of materials 3

    International Nuclear Information System (INIS)

    Beatty, R.L.

    1992-01-01

    This book contains proceedings of the third MRS Symposium on Microwave Processing of Materials. Topics covered include: Microwave Processing Overviews, Numerical Modeling Techniques, Microwave Processing System Design, Microwave/Plasma Processing, Microwave/Materials Interactions, Microwave Processing of Ceramics, Microwave Processing of Polymers, Microwave Processing of Hazardous Wastes, Microwave NDE Techniques and Dielectric Properties and Measurements

  18. Science meeting. Abstracts

    International Nuclear Information System (INIS)

    2000-01-01

    the document is a collection of the science meeting abstracts in the fields of nuclear physics, medical sciences, chemistry, agriculture, environment, engineering, material sciences different aspects of energy and presents research done in 2000 in these fields

  19. The deleuzian abstract machines

    DEFF Research Database (Denmark)

    Werner Petersen, Erik

    2005-01-01

    To most people the concept of abstract machines is connected to the name of Alan Turing and the development of the modern computer. The Turing machine is universal, axiomatic and symbolic (E.g. operating on symbols). Inspired by Foucault, Deleuze and Guattari extended the concept of abstract...... machines to singular, non-axiomatic and diagrammatic machines. That is: Machines which constitute becomings. This presentation gives a survey of the development of the concept of abstract machines in the philosophy of Deleuze and Guatari and the function of these abstract machines in the creation of works...... of art. From Difference and Repetition to Anti-Oedipus, the machines are conceived as binary machines based on the exclusive or inclusive use respectively of the three syntheses: conexa, disjuncta and conjuncta. The machines have a twofold embedment: In the desiring-production and in the social...

  20. Mathematical games, abstract games

    CERN Document Server

    Neto, Joao Pedro

    2013-01-01

    User-friendly, visually appealing collection offers both new and classic strategic board games. Includes abstract games for two and three players and mathematical games such as Nim and games on graphs.

  1. Introduction to abstract algebra

    CERN Document Server

    Smith, Jonathan D H

    2008-01-01

    Taking a slightly different approach from similar texts, Introduction to Abstract Algebra presents abstract algebra as the main tool underlying discrete mathematics and the digital world. It helps students fully understand groups, rings, semigroups, and monoids by rigorously building concepts from first principles. A Quick Introduction to Algebra The first three chapters of the book show how functional composition, cycle notation for permutations, and matrix notation for linear functions provide techniques for practical computation. The author also uses equivalence relations to introduc

  2. Abstract Storage Devices

    OpenAIRE

    Koenig, Robert; Maurer, Ueli; Tessaro, Stefano

    2007-01-01

    A quantum storage device differs radically from a conventional physical storage device. Its state can be set to any value in a certain (infinite) state space, but in general every possible read operation yields only partial information about the stored state. The purpose of this paper is to initiate the study of a combinatorial abstraction, called abstract storage device (ASD), which models deterministic storage devices with the property that only partial information about the state can be re...

  3. Abstracts of contributed papers

    Energy Technology Data Exchange (ETDEWEB)

    1994-08-01

    This volume contains 571 abstracts of contributed papers to be presented during the Twelfth US National Congress of Applied Mechanics. Abstracts are arranged in the order in which they fall in the program -- the main sessions are listed chronologically in the Table of Contents. The Author Index is in alphabetical order and lists each paper number (matching the schedule in the Final Program) with its corresponding page number in the book.

  4. A study on microwave oxidation of landfill leachate—Contributions of microwave-specific effects

    International Nuclear Information System (INIS)

    Chou, Yu-Chieh; Lo, Shang-Lien; Kuo, Jeff; Yeh, Chih-Jung

    2013-01-01

    Highlights: ► pH has an insignificant effect on TOC removals and 550 W has a well performance. ► MOP has well removals of color, UV 254 , and TOC at 550 W/85 °C. ► TOC removals were higher at higher microwave setting (550 W vs. 128 W). ► The microwave-specific effects on TOC removal were usually synergistic in MOP. ► COD analyses showed persulfate decayed rapidly in either MOP or CHO treatment. -- Abstract: Microwave oxidation process (MOP) was evaluated for treatment of landfill leachate. The experimental parameters include pH, temperature, oxidant doses, microwave power setting, and irradiation time. The study explored the microwave-specific effects of the MOP. The contributions of pure thermal, persulfate oxidation and microwave irradiation on TOC removal were quantified. It was then found the combinations of them were usually synergistic in MOP except two of them were antagonistic (128 W/85 °C/1 M Na 2 S 2 O 8 and 128 W/85 °C/2 M Na 2 S 2 O 8 ). At the highest temperature tested (85 °C) in this study, microwave irradiation may cause generation and termination of oxidizing radicals at adverse rates. The study also found that persulfate decayed rapidly in either MOP or conventional heating oxidation (CHO) treatment of landfill leachate

  5. Metacognition and abstract reasoning.

    Science.gov (United States)

    Markovits, Henry; Thompson, Valerie A; Brisson, Janie

    2015-05-01

    The nature of people's meta-representations of deductive reasoning is critical to understanding how people control their own reasoning processes. We conducted two studies to examine whether people have a metacognitive representation of abstract validity and whether familiarity alone acts as a separate metacognitive cue. In Study 1, participants were asked to make a series of (1) abstract conditional inferences, (2) concrete conditional inferences with premises having many potential alternative antecedents and thus specifically conducive to the production of responses consistent with conditional logic, or (3) concrete problems with premises having relatively few potential alternative antecedents. Participants gave confidence ratings after each inference. Results show that confidence ratings were positively correlated with logical performance on abstract problems and concrete problems with many potential alternatives, but not with concrete problems with content less conducive to normative responses. Confidence ratings were higher with few alternatives than for abstract content. Study 2 used a generation of contrary-to-fact alternatives task to improve levels of abstract logical performance. The resulting increase in logical performance was mirrored by increases in mean confidence ratings. Results provide evidence for a metacognitive representation based on logical validity, and show that familiarity acts as a separate metacognitive cue.

  6. Comparative study on contribution of charge-transfer collision to excitations of iron ion between argon radio-frequency inductively-coupled plasma and nitrogen microwave induced plasma

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, Kozue; Wagatsuma, Kazuaki, E-mail: wagatuma@imr.tohoku.ac.jp

    2015-06-01

    This paper describes an ionization/excitation phenomenon of singly-ionized iron occurring in an Okamoto-cavity microwave induced plasma (MIP) as well as an argon radio-frequency inductively-coupled plasma (ICP), by comparing the Boltzmann distribution among iron ionic lines (Fe II) having a wide range of the excitation energy from 4.76 to 9.01 eV. It indicated in both the plasmas that plots of Fe II lines having lower excitation energies (4.76 to 5.88 eV) were fitted on each linear relationship, implying that their excitations were caused by a dominant thermal process such as collision with energetic electron. However, Fe II lines having higher excitation energies (more than 7.55 eV) had a different behavior from each other. In the ICP, Boltzmann plots of Fe II lines assigned to the higher excited levels also followed the normal Boltzmann relationship among the low-lying excited levels, even including a deviation from it in particular excited levels having an excitation energy of ca. 7.8 eV. This deviation can be attributed to a charge-transfer collision with argon ion, which results in the overpopulation of these excited levels, but the contribution is small. On the other hand, the distribution of the high-lying excited levels was non-thermal in the Okamoto-cavity MIP, which did not follow the normal Boltzmann relationship among the low-lying excited levels. A probable reason for the non-thermal characteristics in the MIP is that a charge-transfer collision with nitrogen molecule ion having many vibrational/rotational levels could work for populating the 3d{sup 6}4p (3d{sup 5}4s4p) excited levels of iron ion broadly over an energy range of 7.6–9.0 eV, while collisional excitation by energetic electron would occur insufficiently to excite these high-energy levels. - Highlights: • This paper describes the excitation mechanism of iron ion in Okamoto-cavity MIP in comparison with conventional ICP. • Boltzmann distribution is studied among iron ionic lines of

  7. Determination of bis-carboxyethyl germanium sesquioxide by gas chromatography with microwave-induced plasma-atomic emission detection after derivatization with alkyl chloroformates.

    Science.gov (United States)

    Trikas, E; Zachariadis, G A; Rosenberg, E

    2014-05-01

    Organic germanium compounds, especially Ge-132, more corrctly denoted as bis-beta-carboxyethyl germanium sesquioxide ([Ge(=O)CH2CH2CO2H]2O), are of continued interest as they are said to promote health and display anticancer activity. Although these beneficial effects have never been substantiated by comprehensive clinical studies, this drug can still be obtained through various sources and is usually marketed as a nutritional supplementation rather than an anticancer medication. As the quality standards under which this drug is produced are unknown, the need for an effective quality control of these products arises. To date, Ge-132 is considered generally as a safe compound for application in contrast to inorganic germanium which demonstrates severe renal toxicity. In this paper, a new approach to the determination of Ge-132, based on derivatization by ethyl chloroformate reagent (ECF), in the presence of ethanol and pyridine in the mixture, and subsequent analysis by gas chromatography coupled with microwave-induced plasma-atomic emission detection (GC-MIP-AED), is reported. Reaction conditions of the derivatization procedure were optimized with particular respect to the reagent (ECF) and catalyst (pyridine) concentrations. The proposed method is capable of distinguishing Ge-132 from inorganic germanium. The derivatization procedure was also tested with the use of methyl chloroformate (MCF) as alternative reagent, providing interesting additional information about the nature of the final product and the proposed reaction scheme. Among the two types of chloroformates, i.e., MCF and ECF, the latter proved to be more suitable for the proposed method, providing a calibration curve of superior sensitivity and linearity compared with the one obtained with MCF. The method was applied successfully in three real samples, two food supplements, and one commercially available fertilizer. The analysis of the Ge-132 derivative showed good linearity in the concentration of 1

  8. Abstract Objects of Verbs

    DEFF Research Database (Denmark)

    Robering, Klaus

    2014-01-01

    Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which these obj......Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which...

  9. A Facile Solvent Free Microwave Induced Synthesis and Antibacterial Activity of Some 3-(2’-Hydroxyphenyl-5-(Substituted Aryl-2-Pyrazoline-N1-Caboxaldehydes

    Directory of Open Access Journals (Sweden)

    Birbal Bajia

    2007-01-01

    Full Text Available A novel one pot formylation of 3-(2’-hydroxyphenyl-5-(substituted 2-pyrazolines has been carried out using microwave irradiation with formic acid. solvent free reaction afforded title compounds in 80-90% yield with high purity.synthesized compounds were tested for their antibacterial activity using standard drug.

  10. Effects of microwave on spin tunneling in single-molecule magnets

    Science.gov (United States)

    Kim, Gwang-Hee; Kim, Tae-Suk

    2005-03-01

    We study theoretically the effects of the irradiated microwave on the magnetization in single-molecule magnets (SMMs) like V15 and Fe8. We find that the shape of magnetization depends on the microwave intensity as well as the microwave polarization. The applied microwave field enhances the tunneling probability. The linearly polarized microwaves induce the suppression of magnetization at both positive and negative magnetic fields. The circularly polarized microwaves are absorbed either at one direction of magnetic field or at both directions of magnetic fields, depending on the polarization directions with respect to the direction of longitudinal magnetic field. The generic features we found will be compared with the recent experimental results.

  11. IEEE International conference on plasma science: Conference record--Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-01

    The conference covered the following topics: basic plasma physics; vacuum electronics; gaseous and electrical gas discharges; laser-produced plasma; space plasmas; computational plasma science; plasma diagnostics; electron, ion and plasma sources; intense electron and ion beams; intense beam microwaves; fast wave M/W devices; microwave-plasma interactions; magnetic fusion; MHD; plasma focus; ultrafast z-pinches and x-ray lasers; plasma processing; fast-opening switches; EM and ETH launchers; solid-state plasmas and switches; plasmas for lighting; ball lightning and spherical plasma configurations; and environmental/energy issues. Separate abstracts were prepared for 379 items in this conference.

  12. Microwave quantum logic spectroscopy and control of molecular ions

    DEFF Research Database (Denmark)

    Shi, M.; F. Herskind, P.; Drewsen, M.

    2013-01-01

    A general method for rotational microwave spectroscopy and control of polar molecular ions via direct microwave addressing is considered. Our method makes use of spatially varying AC Stark shifts, induced by far off-resonant, focused laser beams to achieve an effective coupling between...

  13. The Microwave Assisted Composite Manufacturing and Repair (MACMAR) Project

    Science.gov (United States)

    Falker, John; Terrier, Douglas; Clayton, Ronald G.; Worthy, Erica; Sosa, Edward

    2015-01-01

    The inherent microwave property of carbon nanotubes (CNTs) generates the thermal energy required to induce reversible polymerization of the matrix in these self-healing composites. Microwaves will be used to demonstrate advanced composite manufacturing and repair using self-healing composites.

  14. Interstitial microwave hyperthermia treatment investigations

    International Nuclear Information System (INIS)

    Siauve, N; Lormel, C

    2012-01-01

    Microwave ablation also called interstitial hyperthermia is a medical procedure used in the treatment of many cancers, cardiac arrhythmias and other medical conditions. With this medical therapy, an electromagnetic source (antenna) is directly positioned in the target tissue and a sufficient power is injected to necrosis the tissue. The aim of this study is to propose a design procedure and develop the associated tools, for determining the optimal shape, dimensions, type and operating frequency of antenna according to the target volume. In this context, a 3D numerical predictive model of temperature elevation induced by the electric fields and two benches for thermal and electrical tissues properties characterization have been developed. To validate the procedure and the different tools, an experimental bench test which includes interstitial antenna, external microwave generator, phantom that represents the target tissue and measurement system of temperature and electric field has been elaborated.

  15. Scanning Microwave Induced Acoustic Tomography

    National Research Council Canada - National Science Library

    Wang, Lihong V

    2003-01-01

    .... Only non-ionizing radiation is used. No painful breast compression is' required. In addition, our images are free of speckle artifacts, which are prevalent in conventional ultrasound images. Our ultimate goal is to detect early breast cancer.

  16. Scanning Microwave Induced Acoustic Tomography

    National Research Council Canada - National Science Library

    Wang, Lihong V

    2002-01-01

    .... Specifically, our accomplishments include (1) an exact and an approximate time-domain reconstruction algorithm for thermoacoustic tomography in a spherical geometry was derived and published, (2...

  17. Monadic abstract interpreters

    DEFF Research Database (Denmark)

    Sergey, Ilya; Devriese, Dominique; Might, Matthew

    2013-01-01

    -insensitive analysis. To achieve this unification, we develop a systematic method for transforming a concrete semantics into a monadically-parameterized abstract machine. Changing the monad changes the behavior of the machine. By changing the monad, we recover a spectrum of machines—from the original concrete...

  18. WWNPQFT-2013 - Abstracts

    International Nuclear Information System (INIS)

    Cessac, B.; Bianchi, E.; Bellon, M.; Fried, H.; Krajewski, T.; Schubert, C.; Barre, J.; Hofmann, R.; Muller, B.; Raffaelli, B.

    2014-01-01

    The object of this Workshop is to consolidate and publicize new efforts in non perturbative-like Field Theories, relying in Functional Methods, Renormalization Group, and Dyson-Schwinger Equations. A presentation deals with effective vertices and photon-photon scattering in SU(2) Yang-Mills thermodynamics. This document gathers the abstracts of the presentations

  19. 2002 NASPSA Conference Abstracts.

    Science.gov (United States)

    Journal of Sport & Exercise Psychology, 2002

    2002-01-01

    Contains abstracts from the 2002 conference of the North American Society for the Psychology of Sport and Physical Activity. The publication is divided into three sections: the preconference workshop, "Effective Teaching Methods in the Classroom;" symposia (motor development, motor learning and control, and sport psychology); and free…

  20. The Abstraction Engine

    DEFF Research Database (Denmark)

    Fortescue, Michael David

    The main thesis of this book is that abstraction, far from being confined to higher formsof cognition, language and logical reasoning, has actually been a major driving forcethroughout the evolution of creatures with brains. It is manifest in emotive as well as rationalthought. Wending its way th...

  1. Composing Interfering Abstract Protocols

    Science.gov (United States)

    2016-04-01

    Tecnologia , Universidade Nova de Lisboa, Caparica, Portugal. This document is a companion technical report of the paper, “Composing Interfering Abstract...a Ciência e Tecnologia (Portuguese Foundation for Science and Technology) through the Carnegie Mellon Portugal Program under grant SFRH / BD / 33765

  2. Abstract Film and Beyond.

    Science.gov (United States)

    Le Grice, Malcolm

    A theoretical and historical account of the main preoccupations of makers of abstract films is presented in this book. The book's scope includes discussion of nonrepresentational forms as well as examination of experiments in the manipulation of time in films. The ten chapters discuss the following topics: art and cinematography, the first…

  3. Seismic Consequence Abstraction

    International Nuclear Information System (INIS)

    Gross, M.

    2004-01-01

    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274])

  4. Seismic Consequence Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    M. Gross

    2004-10-25

    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274]).

  5. Abstract Objects of Verbs

    DEFF Research Database (Denmark)

    2014-01-01

    Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which these obj...

  6. Abstracts of submitted papers

    International Nuclear Information System (INIS)

    1987-01-01

    The conference proceedings contain 152 abstracts of presented papers relating to various aspects of personnel dosimetry, the dosimetry of the working and living environment, various types of dosemeters and spectrometers, the use of radionuclides in various industrial fields, the migration of radionuclides on Czechoslovak territory after the Chernobyl accident, theoretical studies of some parameters of ionizing radiation detectors, and their calibration. (M.D.)

  7. Metaphors in Abstract Thought

    NARCIS (Netherlands)

    I. Boot (Inge)

    2010-01-01

    textabstractThe aim of the dissertation was to investigate the Conceptual Metaphor Theory (CMT, Lakoff & Johnson, 1980, 1999).The CMT proposes that abstract concepts are partly structured by concrete concepts through the mechanism of metaphorical mapping. In Chapter 2 we wanted to investigate the

  8. SPR 2015. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-04-01

    The volume contains the abstracts of the SPR (society for pediatric radiology) 2015 meeting covering the following issues: fetal imaging, muscoskeletal imaging, cardiac imaging, chest imaging, oncologic imaging, tools for process improvement, child abuse, contrast enhanced ultrasound, image gently - update of radiation dose recording/reporting/monitoring - meaningful or useless meaning?, pediatric thoracic imaging, ALARA.

  9. Reflective Abstraction and Representation.

    Science.gov (United States)

    Lewin, Philip

    Piaget's theory of reflective abstraction can supplement cognitive science models of representation by specifying both the act of construction and the component steps through which knowers pass as they acquire knowledge. But, while approaches suggested by cognitive science supplement Piaget by awakening researchers to the role of auxiliary factors…

  10. Building Safe Concurrency Abstractions

    DEFF Research Database (Denmark)

    Madsen, Ole Lehrmann

    2014-01-01

    Concurrent object-oriented programming in Beta is based on semaphores and coroutines and the ability to define high-level concurrency abstractions like monitors, and rendezvous-based communication, and their associated schedulers. The coroutine mechanism of SIMULA has been generalized into the no...

  11. Poster Session- Extended Abstracts

    Science.gov (United States)

    Jack D. Alexander III; Jean Findley; Brenda K. Kury; Jan L. Beyers; Douglas S. Cram; Terrell T. Baker; Jon C. Boren; Carl Edminster; Sue A. Ferguson; Steven McKay; David Nagel; Trent Piepho; Miriam Rorig; Casey Anderson; Jeanne Hoadley; Paulette L. Ford; Mark C. Andersen; Ed L. Fredrickson; Joe Truett; Gary W. Roemer; Brenda K. Kury; Jennifer Vollmer; Christine L. May; Danny C. Lee; James P. Menakis; Robert E. Keane; Zhi-Liang Zhu; Carol Miller; Brett Davis; Katharine Gray; Ken Mix; William P. Kuvlesky Jr.; D. Lynn Drawe; Marcia G. Narog; Roger D. Ottmar; Robert E. Vihnanek; Clinton S. Wright; Timothy E. Paysen; Burton K. Pendleton; Rosemary L. Pendleton; Carleton S. White; John Rogan; Doug Stow; Janet Franklin; Jennifer Miller; Lisa Levien; Chris Fischer; Emma Underwood; Robert Klinger; Peggy Moore; Clinton S. Wright

    2008-01-01

    Titles found within Poster Session-Extended Abstracts include:Assessment of emergency fire rehabilitation of four fires from the 2000 fire season on the Vale, Oregon, BLM district: review of the density sampling materials and methods: p. 329 Growth of regreen, seeded for erosion control, in the...

  12. Abstract Introduction Materials & Methods

    African Journals Online (AJOL)

    plzfg

    Abstract. Oral administration to male rats of 200mg kg-1 body weight of an extract of Calendula officinalis flowers every day for 60 days did not cause loss of body weight, but decreased significantly the weight of the testis, epididymis, seminal vesicle and ventral prostate. Sperm motility as well as sperm density were reduced ...

  13. Testing abstract behavioral specifications

    NARCIS (Netherlands)

    P.Y.H. Wong; R. Bubel (Richard); F.S. de Boer (Frank); C.P.T. de Gouw (Stijn); M. Gómez-Zamalloa; R Haehnle; K. Meinke; M.A. Sindhu

    2015-01-01

    htmlabstractWe present a range of testing techniques for the Abstract Behavioral Specification (ABS) language and apply them to an industrial case study. ABS is a formal modeling language for highly variable, concurrent, component-based systems. The nature of these systems makes them susceptible to

  14. Impredicative concurrent abstract predicates

    DEFF Research Database (Denmark)

    Svendsen, Kasper; Birkedal, Lars

    2014-01-01

    We present impredicative concurrent abstract predicates { iCAP { a program logic for modular reasoning about concurrent, higher- order, reentrant, imperative code. Building on earlier work, iCAP uses protocols to reason about shared mutable state. A key novel feature of iCAP is the ability to dene...

  15. Leadership Abstracts, 2002.

    Science.gov (United States)

    Wilson, Cynthia, Ed.; Milliron, Mark David, Ed.

    2002-01-01

    This 2002 volume of Leadership Abstracts contains issue numbers 1-12. Articles include: (1) "Skills Certification and Workforce Development: Partnering with Industry and Ourselves," by Jeffrey A. Cantor; (2) "Starting Again: The Brookhaven Success College," by Alice W. Villadsen; (3) "From Digital Divide to Digital Democracy," by Gerardo E. de los…

  16. Circularity and Lambda Abstraction

    DEFF Research Database (Denmark)

    Danvy, Olivier; Thiemann, Peter; Zerny, Ian

    2013-01-01

    unknowns from what is done to them, which we lambda-abstract with functions. The circular unknowns then become dead variables, which we eliminate. The result is a strict circu- lar program a la Pettorossi. This transformation is reversible: given a strict circular program a la Pettorossi, we introduce...

  17. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    Schreiner, R.

    2001-01-01

    The purpose of this work is to develop the Engineered Barrier System (EBS) radionuclide transport abstraction model, as directed by a written development plan (CRWMS M and O 1999a). This abstraction is the conceptual model that will be used to determine the rate of release of radionuclides from the EBS to the unsaturated zone (UZ) in the total system performance assessment-license application (TSPA-LA). In particular, this model will be used to quantify the time-dependent radionuclide releases from a failed waste package (WP) and their subsequent transport through the EBS to the emplacement drift wall/UZ interface. The development of this conceptual model will allow Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department to provide a more detailed and complete EBS flow and transport abstraction. The results from this conceptual model will allow PA0 to address portions of the key technical issues (KTIs) presented in three NRC Issue Resolution Status Reports (IRSRs): (1) the Evolution of the Near-Field Environment (ENFE), Revision 2 (NRC 1999a), (2) the Container Life and Source Term (CLST), Revision 2 (NRC 1999b), and (3) the Thermal Effects on Flow (TEF), Revision 1 (NRC 1998). The conceptual model for flow and transport in the EBS will be referred to as the ''EBS RT Abstraction'' in this analysis/modeling report (AMR). The scope of this abstraction and report is limited to flow and transport processes. More specifically, this AMR does not discuss elements of the TSPA-SR and TSPA-LA that relate to the EBS but are discussed in other AMRs. These elements include corrosion processes, radionuclide solubility limits, waste form dissolution rates and concentrations of colloidal particles that are generally represented as boundary conditions or input parameters for the EBS RT Abstraction. In effect, this AMR provides the algorithms for transporting radionuclides using the flow geometry and radionuclide concentrations determined by other

  18. Application of microwave system in Ethiopia | Ingidayehu | Zede ...

    African Journals Online (AJOL)

    Zede Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 5 (1971) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Application of microwave system in Ethiopia. G Ingidayehu. Abstract. No Abstract ...

  19. Advances in microwaves 3

    CERN Document Server

    Young, Leo

    2013-01-01

    Advances in Microwaves, Volume 3 covers the advances and applications of microwave signal transmission and Gunn devices. This volume contains six chapters and begins with descriptions of ground-station antennas for space communications. The succeeding chapters deal with beam waveguides, which offer interesting possibilities for transmitting microwave energy, as well as with parallel or tubular beams from antenna apertures. A chapter discusses the electron transfer mechanism and the velocity-field characteristics, with a particular emphasis on the microwave properties of Gunn oscillators. The l

  20. The microwave market

    International Nuclear Information System (INIS)

    Bybokas, J.

    1989-01-01

    As superconductors move from the laboratory to the marketplace, it becomes more important for researchers and manufacturers to understand the markets for this technology. The large market for microwave systems represents a major opportunity for high-T c superconductors. Conductor losses are a primary design limitation in conventional microwave systems. The low losses of superconductors at microwave frequencies will allow component designers and system designers to improve their products in many ways. The most important market segments for microwave systems are outlined in this discussion

  1. DEGRO 2017. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-06-15

    The volume includes abstracts of the Annual DEGRO Meeting 2017 covering lectures and poster sessions with the following issues: lymphoma, biology, physics, radioimmunotherapy, sarcomas and rare tumors, prostate carcinoma, lung tumors, benign lesions and new media, mamma carcinoma, gastrointestinal tumors, quality of life, care science and quality assurance, high-technology methods and palliative situation, head-and-neck tumors, brain tumors, central nervous system metastases, guidelines, radiation sensitivity, radiotherapy, radioimmunotherapy.

  2. The deleuzian abstract machines

    DEFF Research Database (Denmark)

    Werner Petersen, Erik

    2005-01-01

    in emphasis from the three syntheses to mappings and rhizomatic diagrams that cut across semiotics or “blow apart regimes of signs”. The aim here is the absolute deterritorialization. Deleuze has shown how abstract machines operate in the philosophy of Foucault, the literature of Proust and Kafka......, and the painting of Bacon. We will finish our presentation by showing how these machines apply to architecture....

  3. SPR 2014. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-05-15

    The proceedings of the SPR 2014 meeting include abstracts on the following topics: Body imaging techniques: practical advice for clinic work; thoracic imaging: focus on the lungs; gastrointestinal imaging: focus on the pancreas and bowel; genitourinary imaging: focus on gonadal radiology; muscoskeletal imaging; focus on oncology; child abuse and nor child abuse: focus on radiography; impact of NMR and CT imaging on management of CHD; education and communication: art and practice in pediatric radiology.

  4. SPR 2014. Abstracts

    International Nuclear Information System (INIS)

    2014-01-01

    The proceedings of the SPR 2014 meeting include abstracts on the following topics: Body imaging techniques: practical advice for clinic work; thoracic imaging: focus on the lungs; gastrointestinal imaging: focus on the pancreas and bowel; genitourinary imaging: focus on gonadal radiology; muscoskeletal imaging; focus on oncology; child abuse and nor child abuse: focus on radiography; impact of NMR and CT imaging on management of CHD; education and communication: art and practice in pediatric radiology.

  5. WWNPQFT-2011 - Abstracts

    International Nuclear Information System (INIS)

    Bianchi, E.; Bender, C.; Culetu, H.; Fried, H.; Grossmann, A.; Hofmann, R.; Le Bellac, M.; Martinetti, P.; Muller, B.; Patras, F.; Raffaeli, B.; Vitting Andersen, J.

    2013-01-01

    The object of this workshop is to consolidate and publicize new efforts in non-perturbative field theories. This year the presentations deal with quantum gravity, non-commutative geometry, fat-tailed wave-functions, strongly coupled field theories, space-times two time-like dimensions, and multiplicative renormalization. A presentation is dedicated to the construction of a nucleon-nucleon potential from an analytical, non-perturbative gauge invariant QCD. This document gathers the abstracts of the presentations

  6. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    J. Prouty

    2006-01-01

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  7. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J. Prouty

    2006-07-14

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  8. In-situ Microwave Brightness Temperature Variability from Ground-based Radiometer Measurements at Dome C in Antarctica Induced by Wind-formed Features

    Science.gov (United States)

    Royer, A.; Picard, G.; Arnaud, L.; Brucker, L.; Fily, M..

    2014-01-01

    Space-borne microwave radiometers are among the most useful tools to study snow and to collect information on the Antarctic climate. They have several advantages over other remote sensing techniques: high sensitivity to snow properties of interest (temperature, grain size, density), subdaily coverage in the polar regions, and their observations are independent of cloud conditions and solar illumination. Thus, microwave radiometers are widely used to retrieve information over snow-covered regions. For the Antarctic Plateau, many studies presenting retrieval algorithms or numerical simulations have assumed, explicitly or not, that the subpixel-scale heterogeneity is negligible and that the retrieved properties were representative of whole pixels. In this presentation, we investigate the spatial variations of brightness temperature over arange of a few kilometers in the Dome C area (Antarctic Plateau).

  9. Thermoacoustic measurement of the temperature during microwave thermotherapy

    Science.gov (United States)

    Lou, Cunguang; Xing, Da; Nie, Liming

    2009-08-01

    Microwave thermotherapy (MT) has been an important treatment in oncology. The measurement of temperature during microwave thermotherapy is vital to ensure the safety of normal tissues. Thermoacoustic signals induced are temperature dependent. This phenomenon demonstrates that the thermal parameters are closely related to the generation of thermoacoustic pressure. Here we present the studies on pulsed microwave-induced thermoacoustic signals toward temperature monitoring of tissue thermotherapy. A high power pulsed microwave was used as thermoacoustic excitation source and heating source simultaneously, thermoacoustic pressure was captured by a multi-element linear transducer array. Excellent agreement was obtained between the inversion calculation results and the actual measurement temperature. The results suggest that thermoacoustic signals can be used to monitor thermotherapy temperature, and has the potential of reconstruct the temperature distribution by filter back-projection algorithm. This method has a great potential to develop into an integrated system for pulsed microwave thermotherapy and curative effect monitoring.

  10. Yttrium oxide transparent ceramics by low-temperature microwave sintering

    International Nuclear Information System (INIS)

    Luo, Junming; Zhong, Zhenchen; Xu, Jilin

    2012-01-01

    Graphical abstract: The figure shows the SEM photos of the surfaces of the Y 2 O 3 transparent ceramic samples obtained by microwave sintering and vacuum sintering. It is clearly demonstrated that the grain distribution of the vacuum sintering sample is not uniform with the smallest and the largest particle size at about 2 μm and 15 μm respectively, while the grain distribution of microwave sintering sample is uniform with the average diameter at about 2–4 μm (the smallest reported so far) and with no abnormal growth-up or coarsening phenomenon. We have further found out that the smaller the grain size, the higher the mechanical and optical properties. Display Omitted Highlights: ► The microwave sintering temperature of the sample is lower compared with vacuum. ► The microwave sintering time of the sample is shorter compared with vacuum. ► The mechanical properties of the microwave sintering sample is improved greatly. ► The Y 2 O 3 grain of microwave sintering sample is the smallest reported so far. -- Abstract: Yttrium oxide (Y 2 O 3 ) transparent ceramics samples have been successfully fabricated by microwave sintering processing at relatively low temperatures. In comparison with the vacuum sintering processing, Y 2 O 3 transparent ceramics can be obtained by microwave sintering at lower sintering temperature and shorter sintering time, and they possess higher transmittances and mechanical properties. The technologies of low-temperature microwave sintering and the relationships of the microstructures and properties of the specified samples have been investigated in detail. We have found out that the low-temperature microwave sintering technique has its obvious advantages over the conventional methods in manufacturing yttrium oxide transparent ceramics.

  11. Integrated microwave photonics

    NARCIS (Netherlands)

    Marpaung, D.A.I.; Roeloffzen, C.G.H.; Heideman, Rene; Leinse, Arne; Sales, S.; Capmany, J.

    2013-01-01

    Microwave photonics (MWP) is an emerging field in which radio frequency (RF) signals are generated, distributed, processed and analyzed using the strength of photonic techniques. It is a technology that enables various functionalities which are not feasible to achieve only in the microwave domain. A

  12. Microwave Enhanced Reactive Distillation

    NARCIS (Netherlands)

    Altman, E.

    2011-01-01

    The application of electromagnetic irradiation in form of microwaves (MW) has gathered the attention of the scientific community in recent years. MW used as an alternative energy source for chemical syntheses (microwave chemistry) can provide clear advantages over conventional heating methods in

  13. Microwave Breast Imaging Techniques

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Rubæk, Tonny

    2010-01-01

    This paper outlines the applicability of microwave radiation for breast cancer detection. Microwave imaging systems are categorized based on their hardware architecture. The advantages and disadvantages of various imaging techniques are discussed. The fundamental tradeoffs are indicated between...... various requirements to be fulfilled in the design of an imaging system for breast cancer detection and some strategies to overcome these limitations....

  14. Program and abstracts

    International Nuclear Information System (INIS)

    1978-01-01

    This volume contains the program and abstracts of the conference. The following topics are included: metal vapor molecular lasers, magnetohydrodynamics, rare gas halide and nuclear pumped lasers, transfer mechanisms in arcs, kinetic processes in rare gas halide lasers, arcs and flows, XeF kinetics and lasers, fundamental processes in excimer lasers, electrode effects and vacuum arcs, electron and ion transport, ion interactions and mobilities, glow discharges, diagnostics and afterglows, dissociative recombination, electron ionization and excitation, rare gas excimers and group VI lasers, breakdown, novel laser pumping techniques, electrode-related discharge phenomena, photon interactions, attachment, plasma chemistry and infrared lasers, electron scattering, and reactions of excited species

  15. ESPR 2015. Abstracts

    International Nuclear Information System (INIS)

    2015-01-01

    The volume includes the abstracts of the ESPR 2015 covering the following topics: PCG (post graduate courses): Radiography; fluoroscopy and general issue; nuclear medicine, interventional radiology and hybrid imaging, pediatric CT, pediatric ultrasound; MRI in childhood. Scientific sessions and task force sessions: International aspects; neuroradiology, neonatal imaging, engineering techniques to simulate injury in child abuse, CT - dose and quality, challenges in the chest, cardiovascular and chest, muscoskeletal, oncology, pediatric uroradiology and abdominal imaging, fetal and postmortem imaging, education and global challenges, neuroradiology - head and neck, gastrointestinal and genitourinary.

  16. ESPR 2015. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-05-10

    The volume includes the abstracts of the ESPR 2015 covering the following topics: PCG (post graduate courses): Radiography; fluoroscopy and general issue; nuclear medicine, interventional radiology and hybrid imaging, pediatric CT, pediatric ultrasound; MRI in childhood. Scientific sessions and task force sessions: International aspects; neuroradiology, neonatal imaging, engineering techniques to simulate injury in child abuse, CT - dose and quality, challenges in the chest, cardiovascular and chest, muscoskeletal, oncology, pediatric uroradiology and abdominal imaging, fetal and postmortem imaging, education and global challenges, neuroradiology - head and neck, gastrointestinal and genitourinary.

  17. IPR 2016. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-05-15

    The volume on the meeting of pediatric radiology includes abstract on the following issues: chest, cardiovascular system, neuroradiology, CT radiation DRs (diagnostic reference levels) and dose reporting guidelines, genitourinary imaging, gastrointestinal radiology, oncology an nuclear medicine, whole body imaging, fetal/neonates imaging, child abuse, oncology and hybrid imaging, value added imaging, muscoskeletal imaging, dose and radiation safety, imaging children - immobilization and distraction techniques, information - education - QI and healthcare policy, ALARA, the knowledge skills and competences for a technologist/radiographer in pediatric radiology, full exploitation of new technological features in pediatric CT, image quality issues in pediatrics, abdominal imaging, interventional radiology, MR contrast agents, tumor - mass imaging, cardiothoracic imaging, ultrasonography.

  18. SPR 2017. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-05-15

    The conference proceedings SPR 2017 include abstracts on the following issues: gastrointestinal radiography - inflammatory bowel diseases, cardiovascular CTA, general muscoskeletal radiology, muscoskeletal congenital development diseases, general pediatric radiology - chest, muscoskeletal imaging - marrow and infectious disorders, state-of-the-art body MR imaging, practical pediatric sonography, quality and professionalism, CT imaging in congenital heart diseases, radiographic courses, body MT techniques, contrast enhanced ultrasound, machine learning, forensic imaging, the radiation dos conundrum - reconciling imaging, imagining and managing, the practice of radiology, interventional radiology, neuroradiology, PET/MR.

  19. Beyond the abstractions?

    DEFF Research Database (Denmark)

    Olesen, Henning Salling

    2006-01-01

      The anniversary of the International Journal of Lifelong Education takes place in the middle of a conceptual landslide from lifelong education to lifelong learning. Contemporary discourses of lifelong learning etc are however abstractions behind which new functions and agendas for adult education...... are set. The ideological discourse of recent policies seems to neglect the fact that history and resources for lifelong learning are different across Europe, and also neglects the multiplicity of adult learners. Instead of refusing the new agendas, however, adult education research should try to dissolve...... learning. Adult education research must fulfil it's potential conversion from normative philosophy to critical and empirical social science....

  20. Parameterized Dataflow (Extended Abstract

    Directory of Open Access Journals (Sweden)

    Dominic Duggan

    2016-10-01

    Full Text Available Dataflow networks have application in various forms of stream processing, for example for parallel processing of multimedia data. The description of dataflow graphs, including their firing behavior, is typically non-compositional and not amenable to separate compilation. This article considers a dataflow language with a type and effect system that captures the firing behavior of actors. This system allows definitions to abstract over actor firing rates, supporting the definition and safe composition of actor definitions where firing rates are not instantiated until a dataflow graph is launched.

  1. ABSTRACTION OF DRIFT SEEPAGE

    International Nuclear Information System (INIS)

    Wilson, Michael L.

    2001-01-01

    Drift seepage refers to flow of liquid water into repository emplacement drifts, where it can potentially contribute to degradation of the engineered systems and release and transport of radionuclides within the drifts. Because of these important effects, seepage into emplacement drifts is listed as a ''principal factor for the postclosure safety case'' in the screening criteria for grading of data in Attachment 1 of AP-3.15Q, Rev. 2, ''Managing Technical Product Inputs''. Abstraction refers to distillation of the essential components of a process model into a form suitable for use in total-system performance assessment (TSPA). Thus, the purpose of this analysis/model is to put the information generated by the seepage process modeling in a form appropriate for use in the TSPA for the Site Recommendation. This report also supports the Unsaturated-Zone Flow and Transport Process Model Report. The scope of the work is discussed below. This analysis/model is governed by the ''Technical Work Plan for Unsaturated Zone Flow and Transport Process Model Report'' (CRWMS MandO 2000a). Details of this activity are in Addendum A of the technical work plan. The original Work Direction and Planning Document is included as Attachment 7 of Addendum A. Note that the Work Direction and Planning Document contains tasks identified for both Performance Assessment Operations (PAO) and Natural Environment Program Operations (NEPO). Only the PAO tasks are documented here. The planning for the NEPO activities is now in Addendum D of the same technical work plan and the work is documented in a separate report (CRWMS MandO 2000b). The Project has been reorganized since the document was written. The responsible organizations in the new structure are the Performance Assessment Department and the Unsaturated Zone Department, respectively. The work plan for the seepage abstraction calls for determining an appropriate abstraction methodology, determining uncertainties in seepage, and providing

  2. Microwave hydrology: A trilogy

    Science.gov (United States)

    Stacey, J. M.; Johnston, E. J.; Girard, M. A.; Regusters, H. A.

    1985-01-01

    Microwave hydrology, as the term in construed in this trilogy, deals with the investigation of important hydrological features on the Earth's surface as they are remotely, and passively, sensed by orbiting microwave receivers. Microwave wavelengths penetrate clouds, foliage, ground cover, and soil, in varying degrees, and reveal the occurrence of standing liquid water on and beneath the surface. The manifestation of liquid water appearing on or near the surface is reported by a microwave receiver as a signal with a low flux level, or, equivalently, a cold temperature. Actually, the surface of the liquid water reflects the low flux level from the cosmic background into the input terminals of the receiver. This trilogy describes and shows by microwave flux images: the hydrological features that sustain Lake Baykal as an extraordinary freshwater resource; manifestations of subsurface water in Iran; and the major water features of the Congo Basin, a rain forest.

  3. Microwave ion source

    Science.gov (United States)

    Leung, Ka-Ngo; Reijonen, Jani; Thomae, Rainer W.

    2005-07-26

    A compact microwave ion source has a permanent magnet dipole field, a microwave launcher, and an extractor parallel to the source axis. The dipole field is in the form of a ring. The microwaves are launched from the middle of the dipole ring using a coaxial waveguide. Electrons are heated using ECR in the magnetic field. The ions are extracted from the side of the source from the middle of the dipole perpendicular to the source axis. The plasma density can be increased by boosting the microwave ion source by the addition of an RF antenna. Higher charge states can be achieved by increasing the microwave frequency. A xenon source with a magnetic pinch can be used to produce intense EUV radiation.

  4. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J.D. Schreiber

    2005-08-25

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport

  5. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    J.D. Schreiber

    2005-01-01

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers

  6. XPS and FTIR spectroscopic study on microwave treated high phosphorus iron ore

    International Nuclear Information System (INIS)

    Omran, Mamdouh; Fabritius, Timo; Elmahdy, Ahmed M.; Abdel-Khalek, Nagui A.; El-Aref, Mortada; Elmanawi, Abd El-Hamid

    2015-01-01

    Highlights: • The effect of microwave radiation on structure and chemical state of high phosphorus iron ore was studied. • FTIR analyses showed that after microwave radiation the functional chemical groups of phosphorus bearing minerals (fluorapatite) dissociated. • High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). • Microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases. - Abstract: A growing interest in microwave heating has emerged recently. Several potential microwave applications regarding minerals’ processing have been investigated. This paper investigates the effect of microwave radiation on Egyptian high phosphorus iron ore. Three different iron ore samples have varying Fe 2 O 3 and P 2 O 5 contents and mineralogical textures were studied. A comparative study has been carried out between untreated and microwave treated iron ore. XRD and FTIR analyses showed that after microwave radiation the crystallinity of iron bearing minerals (hematite) increased, while the functional chemical groups of phosphorus bearing minerals (fluorapatite) and other gangues dissociated. High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). This means that after microwave radiation iron oxide (hematite, Fe 3+ ) transformed into more magnetic phase. The results indicated that microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases

  7. Problems in abstract algebra

    CERN Document Server

    Wadsworth, A R

    2017-01-01

    This is a book of problems in abstract algebra for strong undergraduates or beginning graduate students. It can be used as a supplement to a course or for self-study. The book provides more variety and more challenging problems than are found in most algebra textbooks. It is intended for students wanting to enrich their learning of mathematics by tackling problems that take some thought and effort to solve. The book contains problems on groups (including the Sylow Theorems, solvable groups, presentation of groups by generators and relations, and structure and duality for finite abelian groups); rings (including basic ideal theory and factorization in integral domains and Gauss's Theorem); linear algebra (emphasizing linear transformations, including canonical forms); and fields (including Galois theory). Hints to many problems are also included.

  8. ICENES 2007 Abstracts

    International Nuclear Information System (INIS)

    Sahin, S.

    2007-01-01

    In this book Conference Program and Abstracts were included 13th International Conference on Emerging Nuclear Energy Systems which held between 03-08 June 2007 in Istanbul, Turkey. The main objective of International Conference series on Emerging Nuclear Energy Systems (ICENES) is to provide an international scientific and technical forum for scientists, engineers, industry leaders, policy makers, decision makers and young professionals who will shape future energy supply and technology , for a broad review and discussion of various advanced, innovative and non-conventional nuclear energy production systems. The main topics of 159 accepted papers from 35 countries are fusion science and technology, fission reactors, accelerator driven systems, transmutation, laser in nuclear technology, radiation shielding, nuclear reactions, hydrogen energy, solar energy, low energy physics and societal issues

  9. Gold Nanoparticle Microwave Synthesis

    International Nuclear Information System (INIS)

    Krantz, Kelsie E.; Christian, Jonathan H.; Coopersmith, Kaitlin; Washington II, Aaron L.; Murph, Simona H.

    2016-01-01

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however, polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, and a reduction in reaction time from 10 minutes to 1 minute; this maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  10. Gold Nanoparticle Microwave Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Krantz, Kelsie E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Christian, Jonathan H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coopersmith, Kaitlin [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Murph, Simona H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-27

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however, polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, and a reduction in reaction time from 10 minutes to 1 minute; this maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  11. MICROWAVE STABILIZATION AND MICROWAVE-STIMULATED FIXATION

    NARCIS (Netherlands)

    BOON, ME; KOK, LP

    1990-01-01

    In microwave stabilization the tissue is prepared for histoprocessing through the uniformly distributed increased temperature. This procedure can be called unique: Exclusively by the uniform well-controlled temperature rise to 55-degrees-C it is possible to stabilize the tissue to the needed

  12. Microwaves - the hidden danger

    International Nuclear Information System (INIS)

    Brodeur, P.

    1987-01-01

    Today, highly frequent radio waves are regarded as undangerous to man. Diseases seen at radar-technicians during the 2nd World War, however, indicated that microwaves applied in radar systems were hazardous to health. The Russian work medicine has been knowing microwave-caused hazards in industry since the beginning of the thirties. Therefore in some East-European countries there are terms of protection and severe norms of safety for the staying of persons in the radiation sphere of microwaves. (orig.) [de

  13. Advances in microwaves

    CERN Document Server

    Young, Leo

    1967-01-01

    Advances in Microwaves, Volume 2 focuses on the developments in microwave solid-state devices and circuits. This volume contains six chapters that also describe the design and applications of diplexers and multiplexers. The first chapter deals with the parameters of the tunnel diode, oscillators, amplifiers and frequency converter, followed by a simple physical description and the basic operating principles of the solid state devices currently capable of generating coherent microwave power, including transistors, harmonic generators, and tunnel, avalanche transit time, and diodes. The next ch

  14. Advances in microwaves 4

    CERN Document Server

    Young, Leo

    2013-01-01

    Advances in Microwaves, Volume 4 covers some innovations in the devices and applications of microwaves. This volume contains three chapters and begins with a discussion of the application of microwave phasers and time delay elements as beam steering elements in array radars. The next chapter provides first an overview of the technical aspects and different types of millimeter waveguides, followed by a survey of their application to railroads. The last chapter examines the general mode of conversion properties of nonuniform waveguides, such as waveguide tapers, using converted Maxwell's equatio

  15. Experimental investigation of gas heating and dissociation in a microwave plasma torch at atmospheric pressure

    International Nuclear Information System (INIS)

    Su, Liu; Kumar, Rajneesh; Ogungbesan, Babajide; Sassi, Mohamed

    2014-01-01

    Highlights: • Atmospheric-pressure microwave plasma torch. • Gas heating and dissociation. • Parametric studies of plasma operating conditions. • Local thermal equilibrium plasma. - Abstract: Experimental investigations are made to understand gas heating and dissociation in a microwave (MW) plasma torch at atmospheric pressure. The MW induced plasma torch operates at 2.45 GHz frequency and up to 2 kW power. Three different gas mixtures are injected in the form of axial flow and swirl flow in a quartz tube plasma torch to experimentally investigate the MW plasma to gas energy transfer. Air–argon, air–air and air–nitrogen plasmas are formed and their operational ranges are determined in terms of gas flow rates and MW power. Visual observations, optical emission spectroscopy and K-type thermocouple measurements are used to characterize the plasma. The study reveals that the plasma structure is highly dependent on the carrier gas type, gas flow rate, and MW power. However, the plasma gas temperature is shown not to vary much with these parameters. Further spectral and analytical analysis show that the plasma is in thermal equilibrium and presents very good energy coupling between the microwave power and gas heating and dissociation. The MW plasma torch outlet temperature is also measured and found to be suitable for many thermal heating and chemical dissociation applications

  16. Exoplanets and Multiverses (Abstract)

    Science.gov (United States)

    Trimble, V.

    2016-12-01

    (Abstract only) To the ancients, the Earth was the Universe, of a size to be crossed by a god in a day, by boat or chariot, and by humans in a lifetime. Thus an exoplanet would have been a multiverse. The ideas gradually separated over centuries, with gradual acceptance of a sun-centered solar system, the stars as suns likely to have their own planets, other galaxies beyond the Milky Way, and so forth. And whenever the community divided between "just one' of anything versus "many," the "manies" have won. Discoveries beginning in 1991 and 1995 have gradually led to a battalion or two of planets orbiting other stars, very few like our own little family, and to moderately serious consideration of even larger numbers of other universes, again very few like our own. I'm betting, however, on habitable (though not necessarily inhabited) exoplanets to be found, and habitable (though again not necessarily inhabited) universes. Only the former will yield pretty pictures.

  17. Book of Abstracts

    International Nuclear Information System (INIS)

    2013-06-01

    ANIMMA 2013 is the third of a series of conferences devoted to endorsing and promoting scientific and technical activities based on nuclear instrumentation and measurements. The main objective of ANIMMA conference is to unite the various scientific communities not only involved in nuclear instrumentation and measurements, but also in nuclear medicine and radiation. The conference is all about getting scientists, engineers and the industry to meet, exchange cultures and identify new scientific and technical prospects to help overcome both current and future unresolved issues. The conference provides scientists and engineers with a veritable opportunity to compare their latest research and development in different areas: physics, nuclear energy, nuclear fuel cycle, safety, security, future energies (GEN III+, GENIV, ITER, ...). The conference topics include instrumentation and measurement methods for: Fundamental physics; Fusion diagnostics and technology; Nuclear power reactors; Research reactors; Nuclear fuel cycle; Decommissioning, dismantling and remote handling; Safeguards, homeland security; Severe accident monitoring; Environmental and medical sciences; Education, training and outreach. This document brings together the abstracts of the presentations. Each presentation (full paper) is analysed separately and entered in INIS

  18. SENSE 2010, Abstracts

    International Nuclear Information System (INIS)

    Lumsden, M.D.; Argyriou, D.N.; Inosov, D.

    2012-01-01

    The microscopic origin of unconventional superconductivity continues to attract the attention of the condensed matter community. Whereas rare-earth / actinide-based intermetallic and copper oxide-based high temperature superconductors are studied for more than twenty years, the iron-based superconductors have been in the focus of interest since their recent discovery. Inelastic neutron scattering experiments have been of particular importance for the understanding of the magnetic and superconducting properties of these compounds. With its 29 talks and 14 posters the workshop provided a forum for the 71 registered participants to review and discuss experimental achievements, recognize the observed synergy and differences as well as discuss theoretical efforts to identify the symmetry of the superconducting order parameter in addition to the coupling mechanisms of the Cooper pairs. The workshop covered different topics relevant for the study of unconventional superconductivity. Magnetization and lattice dynamics such as spin resonances, phonons, magnetic and other excitations as studied by spectroscopic methods were presented. Investigations of (doping, pressure and magnetic field dependent) phase diagrams, electronic states as well as vortex physics by the various diffraction techniques were also addressed. This document gathers only the abstracts of the papers. (authors)

  19. Automated Supernova Discovery (Abstract)

    Science.gov (United States)

    Post, R. S.

    2015-12-01

    (Abstract only) We are developing a system of robotic telescopes for automatic recognition of Supernovas as well as other transient events in collaboration with the Puckett Supernova Search Team. At the SAS2014 meeting, the discovery program, SNARE, was first described. Since then, it has been continuously improved to handle searches under a wide variety of atmospheric conditions. Currently, two telescopes are used to build a reference library while searching for PSN with a partial library. Since data is taken every night without clouds, we must deal with varying atmospheric and high background illumination from the moon. Software is configured to identify a PSN, reshoot for verification with options to change the run plan to acquire photometric or spectrographic data. The telescopes are 24-inch CDK24, with Alta U230 cameras, one in CA and one in NM. Images and run plans are sent between sites so the CA telescope can search while photometry is done in NM. Our goal is to find bright PSNs with magnitude 17.5 or less which is the limit of our planned spectroscopy. We present results from our first automated PSN discoveries and plans for PSN data acquisition.

  20. Stellar Presentations (Abstract)

    Science.gov (United States)

    Young, D.

    2015-12-01

    (Abstract only) The AAVSO is in the process of expanding its education, outreach and speakers bureau program. powerpoint presentations prepared for specific target audiences such as AAVSO members, educators, students, the general public, and Science Olympiad teams, coaches, event supervisors, and state directors will be available online for members to use. The presentations range from specific and general content relating to stellar evolution and variable stars to specific activities for a workshop environment. A presentation—even with a general topic—that works for high school students will not work for educators, Science Olympiad teams, or the general public. Each audience is unique and requires a different approach. The current environment necessitates presentations that are captivating for a younger generation that is embedded in a highly visual and sound-bite world of social media, twitter and U-Tube, and mobile devices. For educators, presentations and workshops for themselves and their students must support the Next Generation Science Standards (NGSS), the Common Core Content Standards, and the Science Technology, Engineering and Mathematics (STEM) initiative. Current best practices for developing relevant and engaging powerpoint presentations to deliver information to a variety of targeted audiences will be presented along with several examples.

  1. Effects of microwave radiation on brain energy metabolism and related mechanisms

    OpenAIRE

    Hao, Yan-Hui; Zhao, Li; Peng, Rui-Yun

    2015-01-01

    With the rapid development of electronic technologies, anxiety regarding the potential health hazards induced by microwave radiation (MW) has been growing in recent years. The brain is one of the most sensitive target organs for microwave radiation, where mitochondrial injury occurs earlier and more severely than in other organs. Energy metabolism disorders do play an important role during the process of microwave radiation-induced brain damage. In this paper, we will review the biological ef...

  2. The influence of microwave irradiation on rocks for microwave-assisted underground excavation

    Directory of Open Access Journals (Sweden)

    Ferri Hassani

    2016-02-01

    Full Text Available Demand is growing for explosive-free rock breakage systems for civil and mining engineering, and space industry applications. This paper highlights the work being undertaken in the Geomechanics Laboratory of McGill University to make a real application of microwave-assisted mechanical rock breakage to full-face tunneling machines and drilling. Comprehensive laboratory tests investigated the effect of microwave radiation on temperature profiles and strength reduction in hard rocks (norite, granite, and basalt for a range of exposure times and microwave power levels. The heating rate on the surface of the rock specimens linearly decreased with distance between the sample and the microwave antenna, regardless of microwave power level and exposure time. Tensile and uniaxial compressive strengths were reduced with increasing exposure time and power level. Scanning electron micrographs (SEMs highlighted fracture development in treated basalt. It was concluded that the microwave power level has a strong positive influence on the amount of heat damage induced to the rock surface. Numerical simulations of electric field intensity and wave propagation conducted with COMSOL Multiphysics® software generated temperature profiles that were in close agreement with experimental results.

  3. IEEE conference record -- abstracts: 1995 IEEE international conference on plasma science

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    Topics covered at this meeting are: computational plasma physics; slow wave devices; basic phenomena in fully ionized plasmas; microwave-plasma interactions; space plasmas; fast wave devices; plasma processing; plasma, ion, and electron sources; vacuum microelectronics; basic phenomena in partially ionized gases; microwave systems; plasma diagnostics; magnetic fusion theory/experiment; fast opening switches; laser-produced plasmas; dense plasma focus; intense ion and electron beams; plasmas for lighting; fast z-pinches and x-ray lasers; intense beam microwaves; ball lightning/spherical plasma configuration; environmental plasma science; EM and ETH launchers; and environmental/energy issues in plasma science. Separate abstracts were prepared for most of the individual papers.

  4. Microwave photonics shines

    Science.gov (United States)

    Won, Rachel

    2011-12-01

    The combination of microwave photonics and optics has advanced many applications in defence, wireless communications, imaging and network infrastructure. Rachel Won talks to Jianping Yao from the University of Ottawa in Canada about the importance of this growing field.

  5. Emitron: microwave diode

    Science.gov (United States)

    Craig, G.D.; Pettibone, J.S.; Drobot, A.T.

    1982-05-06

    The invention comprises a new class of device, driven by electron or other charged particle flow, for producing coherent microwaves by utilizing the interaction of electromagnetic waves with electron flow in diodes not requiring an external magnetic field. Anode and cathode surfaces are electrically charged with respect to one another by electron flow, for example caused by a Marx bank voltage source or by other charged particle flow, for example by a high energy charged particle beam. This produces an electric field which stimulates an emitted electron beam to flow in the anode-cathode region. The emitted electrons are accelerated by the electric field and coherent microwaves are produced by the three dimensional spatial and temporal interaction of the accelerated electrons with geometrically allowed microwave modes which results in the bunching of the electrons and the pumping of at least one dominant microwave mode.

  6. Abstraction of Drift Seepage

    Energy Technology Data Exchange (ETDEWEB)

    J.T. Birkholzer

    2004-11-01

    This model report documents the abstraction of drift seepage, conducted to provide seepage-relevant parameters and their probability distributions for use in Total System Performance Assessment for License Application (TSPA-LA). Drift seepage refers to the flow of liquid water into waste emplacement drifts. Water that seeps into drifts may contact waste packages and potentially mobilize radionuclides, and may result in advective transport of radionuclides through breached waste packages [''Risk Information to Support Prioritization of Performance Assessment Models'' (BSC 2003 [DIRS 168796], Section 3.3.2)]. The unsaturated rock layers overlying and hosting the repository form a natural barrier that reduces the amount of water entering emplacement drifts by natural subsurface processes. For example, drift seepage is limited by the capillary barrier forming at the drift crown, which decreases or even eliminates water flow from the unsaturated fractured rock into the drift. During the first few hundred years after waste emplacement, when above-boiling rock temperatures will develop as a result of heat generated by the decay of the radioactive waste, vaporization of percolation water is an additional factor limiting seepage. Estimating the effectiveness of these natural barrier capabilities and predicting the amount of seepage into drifts is an important aspect of assessing the performance of the repository. The TSPA-LA therefore includes a seepage component that calculates the amount of seepage into drifts [''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504], Section 6.3.3.1)]. The TSPA-LA calculation is performed with a probabilistic approach that accounts for the spatial and temporal variability and inherent uncertainty of seepage-relevant properties and processes. Results are used for subsequent TSPA-LA components that may handle, for example, waste package

  7. Book of abstracts

    International Nuclear Information System (INIS)

    1987-01-01

    The document contains abstracts of 24 review papers, 24 invited papers, 24 oral contributions and 120 posters. 10 review papers summarize the status of laser fusion research and progress in high-power laser facilities in major world laboratories. Four papers review research programs (laser-matter interaction studies and X-ray source development) based on KrF laser systems. Other review papers discuss the problems of laser energy conversion into X-rays in laser-heated cavities, X-ray lasing at shorter wavelengths, optimization of targets for inertial fusion. Two review papers are devoted to light ion fusion. The subjects of most invited papers are special problems of current laser plasma research, such as hot electron generation, nonlinear resonance absorption, energy accumulation limits, pellet ignition, conversion of laser light into X-rays, high-pressure plasma generation. Three invited papers review laser plasma research in Czechoslovakia, Poland and Spain. One paper suggests a new method of producing muonic superdense matter. The remaining inivited papers deal with the progress in XUV lasers and with laser plasma applications for further laser development. Of the papers accepted for oral presentation 12 papers discuss various problems of laser-plasma interaction; 4 papers deal with laser targets, 4 papers with laser-initiated X-ray sources, 3 papers with the diagnostics of laser-produced plasma. The last oral contribution presents the main principles of the excimer laser theory. The largest group of posters is related to laser-plasma interaction and energy absorption problems, to laser-target interaction and various methods of laser plasma diagnostics. The other posters deal with plasma applications in laser development, plasma mirrors, Brillouin and Raman scattering, X-ray emission, harmonic generation, electron acceleration, production of high-Z plasmas and other related problems. (J.U.)

  8. Abstraction of Drift Seepage

    International Nuclear Information System (INIS)

    J.T. Birkholzer

    2004-01-01

    This model report documents the abstraction of drift seepage, conducted to provide seepage-relevant parameters and their probability distributions for use in Total System Performance Assessment for License Application (TSPA-LA). Drift seepage refers to the flow of liquid water into waste emplacement drifts. Water that seeps into drifts may contact waste packages and potentially mobilize radionuclides, and may result in advective transport of radionuclides through breached waste packages [''Risk Information to Support Prioritization of Performance Assessment Models'' (BSC 2003 [DIRS 168796], Section 3.3.2)]. The unsaturated rock layers overlying and hosting the repository form a natural barrier that reduces the amount of water entering emplacement drifts by natural subsurface processes. For example, drift seepage is limited by the capillary barrier forming at the drift crown, which decreases or even eliminates water flow from the unsaturated fractured rock into the drift. During the first few hundred years after waste emplacement, when above-boiling rock temperatures will develop as a result of heat generated by the decay of the radioactive waste, vaporization of percolation water is an additional factor limiting seepage. Estimating the effectiveness of these natural barrier capabilities and predicting the amount of seepage into drifts is an important aspect of assessing the performance of the repository. The TSPA-LA therefore includes a seepage component that calculates the amount of seepage into drifts [''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504], Section 6.3.3.1)]. The TSPA-LA calculation is performed with a probabilistic approach that accounts for the spatial and temporal variability and inherent uncertainty of seepage-relevant properties and processes. Results are used for subsequent TSPA-LA components that may handle, for example, waste package corrosion or radionuclide transport

  9. Effects of microwave heating on the thermal states of biological tissues

    African Journals Online (AJOL)

    Effects of microwave heating on the thermal states of biological tissues. Nabil TM El-dabe, Mona AA Mohamed, Asma F El-Sayed. Abstract. A mathematical analysis of microwave heating equations in one-dimensional multi-layer model has been discussed. Maxwell's equations and transient bioheat transfer equation were ...

  10. Microwave system engineering principles

    CERN Document Server

    Raff, Samuel J

    1977-01-01

    Microwave System Engineering Principles focuses on the calculus, differential equations, and transforms of microwave systems. This book discusses the basic nature and principles that can be derived from thermal noise; statistical concepts and binomial distribution; incoherent signal processing; basic properties of antennas; and beam widths and useful approximations. The fundamentals of propagation; LaPlace's Equation and Transmission Line (TEM) waves; interfaces between homogeneous media; modulation, bandwidth, and noise; and communications satellites are also deliberated in this text. This bo

  11. A microwave powered sensor assembly for microwave ovens

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a microwave powered sensor assembly for micro- wave ovens. The microwave powered sensor assembly comprises a microwave antenna for generating an RF antenna signal in response to microwave radiation at a predetermined excitation frequency. A dc power supply circuit...... of the microwave powered sensor assembly is operatively coupled to the RF antenna signal for extracting energy from the RF antenna signal and produce a power supply voltage. A sensor is connected to the power supply voltage and configured to measure a physical or chemical property of a food item under heating...... in a microwave oven chamber....

  12. Coupled microwave/photoassisted methods for environmental remediation.

    Science.gov (United States)

    Horikoshi, Satoshi; Serpone, Nick

    2014-11-05

    The microwave-induced acceleration of photocatalytic reactions was discovered serendipitously in the late 1990s. The activity of photocatalysts is enhanced significantly by both microwave radiation and UV light. Particularly relevant, other than as a heat source, was the enigmatic phenomenon of the non-thermal effect(s) of the microwave radiation that facilitated photocatalyzed reactions, as evidenced when examining various model contaminants in aqueous media. Results led to an examination of the possible mechanism(s) of the microwave effect(s). In the present article we contend that the microwaves' non-thermal effect(s) is an important factor in the enhancement of TiO2-photoassisted reactions involving the decomposition of organic pollutants in model wastewaters by an integrated (coupled) microwave-/UV-illumination method (UV/MW). Moreover, such coupling of no less than two irradiation methods led to the fabrication and ultimate investigation of microwave discharged electrodeless lamps (MDELs) as optimal light sources; their use is also described. The review focuses on the enhanced activity of photocatalytic reactions when subjected to microwave radiation and concentrates on the authors' research of the past few years.

  13. Mechanism for microwave heating of 1-(4'-cyanophenyl)-4-propylcyclohexane characterized by in situ microwave irradiation NMR spectroscopy.

    Science.gov (United States)

    Tasei, Yugo; Yamakami, Takuya; Kawamura, Izuru; Fujito, Teruaki; Ushida, Kiminori; Sato, Motoyasu; Naito, Akira

    2015-05-01

    Microwave heating is widely used to accelerate organic reactions and enhance the activity of enzymes. However, the detailed molecular mechanism for the effect of microwave on chemical reactions is not yet fully understood. To investigate the effects of microwave heating on organic compounds, we have developed an in situ microwave irradiation NMR spectroscopy. (1)H NMR spectra of 1-(4'-cyanophenyl)-4-propylcyclohexane (PCH3) in the liquid crystalline and isotropic phases were observed under microwave irradiation. When the temperature was regulated at slightly higher than the phase transition temperature (Tc=45 °C) under a gas flow temperature control system, liquid crystalline phase mostly changed to the isotropic phase. Under microwave irradiation and with the gas flow temperature maintained at 20 °C, which is 25 °C below the Tc, the isotropic phase appeared stationary as an approximately 2% fraction in the liquid crystalline phase. The temperature of the liquid crystalline state was estimated to be 38 °C according to the line width, which is at least 7 °C lower than the Tc. The temperature of this isotropic phase should be higher than 45 °C, which is considered to be a non-equilibrium local heating state induced by microwave irradiation. Microwaves at a power of 195 W were irradiated to the isotropic phase of PCH3 at 50 °C and after 2 min, the temperature reached 220 °C. The temperature of PCH3 under microwave irradiation was estimated by measurement of the chemical shift changes of individual protons in the molecule. These results demonstrate that microwave heating generates very high temperature within a short time using an in situ microwave irradiation NMR spectrometer. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. (abstract) Tropospheric Calibration for the Mars Observer Gravity Wave Experiment

    Science.gov (United States)

    Walter, Steven J.; Armstrong, John

    1994-01-01

    In spring 1993, microwave radiometer-based tropospheric calibration was provided for the Mars Observer gravitational wave search. The Doppler shifted X-band radio signals propagating between Earth and the Mars Observer satellite were precisely measured to determine path length variations that might signal passage of gravitational waves. Experimental sensitivity was restricted by competing sources of variability in signal transit time. Principally, fluctuations in the solar wind and ionospheric plasma density combined with fluctions in tropospheric refractivity determined the detection limit. Troposphere-induced path delay fluctions are dominated by refractive changes caused by water vapor inhomogeneities blowing through the signal path. Since passive microwave remote sensing techniques are able to determine atmospheric propagation delays, radiometer-based tropospheric calibration was provided at the Deep Space Network Uranus tracking site (DSS-15). Two microwave water vapor radiometers (WVRs), a microwave temperature profiler (MTP), and a ground based meterological station were deployed to determine line-of-sight vapor content and vertical temperature profile concurrently with Mars Observer tracking measurements. This calibration system provided the capability to correct Mars Observer Doppler data for troposphere-induced path variations. We present preliminary analysis of the Doppler and WVR data sets illustrating the utility of WVRs to calibrate Doppler data. This takes an important step toward realizing the ambitious system required to support future Ka-band Cassini satellite gravity wave tropospheric calibration system.

  15. Microwave Bandpass Filter Based on Mie-Resonance Extraordinary Transmission.

    Science.gov (United States)

    Pan, Xiaolong; Wang, Haiyan; Zhang, Dezhao; Xun, Shuang; Ouyang, Mengzhu; Fan, Wentao; Guo, Yunsheng; Wu, Ye; Huang, Shanguo; Bi, Ke; Lei, Ming

    2016-01-01

    Microwave bandpass filter structure has been designed and fabricated by filling the periodically metallic apertures with dielectric particles. The microwave cannot transmit through the metallic subwavelength apertures. By filling the metallic apertures with dielectric particles, a transmission passband with insertion loss 2 dB appears at the frequency of 10-12 GHz. Both simulated and experimental results show that the passband is induced by the Mie resonance of the dielectric particles. In addition, the passband frequency can be tuned by the size and the permittivity of the dielectric particles. This approach is suitable to fabricate the microwave bandpass filters.

  16. Microwave Bandpass Filter Based on Mie-Resonance Extraordinary Transmission.

    Directory of Open Access Journals (Sweden)

    Xiaolong Pan

    Full Text Available Microwave bandpass filter structure has been designed and fabricated by filling the periodically metallic apertures with dielectric particles. The microwave cannot transmit through the metallic subwavelength apertures. By filling the metallic apertures with dielectric particles, a transmission passband with insertion loss 2 dB appears at the frequency of 10-12 GHz. Both simulated and experimental results show that the passband is induced by the Mie resonance of the dielectric particles. In addition, the passband frequency can be tuned by the size and the permittivity of the dielectric particles. This approach is suitable to fabricate the microwave bandpass filters.

  17. Microwave and Submillimeter-Wave Measurements of HD 12C 16O in the ν 4, ν 5, and ν 6 Bands: Evidence of Vibrational Induced Rotational Axis Switching ("VIRAS")

    Science.gov (United States)

    Perrin, A.; Flaud, J.-M.; Margulès, L.; Demaison, J.; Mäder, H.; Wörmke, S.

    2002-12-01

    The rotational spectrum of HDCO in the 4 1, 5 1, and 6 1 excited vibrational states has been investigated in Lille and Kiel using a sample enriched in deuterium. In Lille, the measurements were performed in the millimeter region (160-600 GHz). The spectra in Kiel were recorded using Fourier transform microwave spectrometers in the regions around 8-18 and 18-26 GHz, employing a rectangular waveguide of length 12 m and a circular waveguide of length 36 m, respectively. These results were combined with the 4 1, 5 1, and 6 1 infrared energy levels which were obtained from a previous analysis of FTS spectra of the ν 4 (CHD bend), ν 5 (CHD rocking), and ν 6 bands (out of plane bend) recorded in the 10-μm region at Giessen (A. Perrin, J.-M. Flaud, M. Smirnov, and M. Lock, J. Mol. Spectrosc.203, 175-187 (2000)). The energy level calculation of the 4 1, 5 1, and 6 1 interacting states accounts for the usual A- and B-type Coriolis resonances in the 5 1⇔6 1 and 4 1⇔6 1 off diagonals blocks. In addition, since the energy levels of the 5 1 and 6 1 states are very strongly resonating, it proved necessary, as in our previous study, to use a { Jx, Jz} nonorthorhombic term in the 5 1 and 6 1v-diagonal blocks of the Hamiltonian matrix in order to reproduce properly the observed microwave transitions and infrared energy levels. Therefore, this work confirms that HDCO is a good example of the vibrational induced rotational axis switching ("VIRAS") effect.

  18. Design of a microwave calorimeter for the microwave tokamak experiment

    International Nuclear Information System (INIS)

    Marinak, M.

    1988-01-01

    The initial design of a microwave calorimeter for the Microwave Tokamak Experiment is presented. The design is optimized to measure the refraction and absorption of millimeter rf microwaves as they traverse the toroidal plasma of the Alcator C tokamak. Techniques utilized can be adapted for use in measuring high intensity pulsed output from a microwave device in an environment of ultra high vacuum, intense fields of ionizing and non-ionizing radiation and intense magnetic fields. 16 refs

  19. Microwave dynamics of YBCO bi-epitaxial Josephson structures

    DEFF Research Database (Denmark)

    Constantinian, K. Y.; Ovsyannikov, G. A.; Mashtakov, A. D.

    1996-01-01

    The processes of interaction of microwaves (frequency View the MathML source) with a single high-Tc superconducting YBa2Cu3Ox (YBCO) bi-epitaxial grain-boundary junction and with an array of two junctions connected in series, have been investigated experimentally at temperatures T = 4.2− 77 K......, as well as the subharmonic detector response at weak magnetic fields φ microwave field induced frequency synchronization of two series connected bi-epitaxial YBCO junctions....

  20. Microwave engineering concepts and fundamentals

    CERN Document Server

    Khan, Ahmad Shahid

    2014-01-01

    Detailing the active and passive aspects of microwaves, Microwave Engineering: Concepts and Fundamentals covers everything from wave propagation to reflection and refraction, guided waves, and transmission lines, providing a comprehensive understanding of the underlying principles at the core of microwave engineering. This encyclopedic text not only encompasses nearly all facets of microwave engineering, but also gives all topics—including microwave generation, measurement, and processing—equal emphasis. Packed with illustrations to aid in comprehension, the book: •Describes the mathematical theory of waveguides and ferrite devices, devoting an entire chapter to the Smith chart and its applications •Discusses different types of microwave components, antennas, tubes, transistors, diodes, and parametric devices •Examines various attributes of cavity resonators, semiconductor and RF/microwave devices, and microwave integrated circuits •Addresses scattering parameters and their properties, as well a...

  1. Balanced microwave filters

    CERN Document Server

    Hong, Jiasheng; Medina, Francisco; Martiacuten, Ferran

    2018-01-01

    This book presents and discusses strategies for the design and implementation of common-mode suppressed balanced microwave filters, including, narrowband, wideband, and ultra-wideband filters This book examines differential-mode, or balanced, microwave filters by discussing several implementations of practical realizations of these passive components. Topics covered include selective mode suppression, designs based on distributed and semi-lumped approaches, multilayer technologies, defect ground structures, coupled resonators, metamaterials, interference techniques, and substrate integrated waveguides, among others. Divided into five parts, Balanced Microwave Filters begins with an introduction that presents the fundamentals of balanced lines, circuits, and networks. Part 2 covers balanced transmission lines with common-mode noise suppression, including several types of common-mode filters and the application of such filters to enhance common-mode suppression in balanced bandpass filters. Next, Part 3 exa...

  2. Microwave Tokamak Experiment

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The Microwave Tokamak Experiment, now under construction at the Laboratory, will use microwave heating from a free-electron laser. The intense microwave pulses will be injected into the tokamak to realize several goals, including a demonstration of the effects of localized heat deposition within magnetically confined plasma, a better understanding of energy confinement in tokamaks, and use of the new free-electron laser technology for plasma heating. The experiment, soon to be operational, provides an opportunity to study dense plasmas heated by powers unprecedented in the electron-cyclotron frequency range required by the especially high magnetic fields used with the MTX and needed for reactors. 1 references, 5 figures, 3 tables

  3. Electromagnetic properties of carbonyl iron and their microwave ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. The complex permittivity, permeability and microwave-absorbing properties of rubber composites filled with carbonyl iron are measured at frequencies from 2–18 GHz. The results indicate that the reflection loss peak shifts towards low frequency region with increasing layer thickness or increasing weight concentra-.

  4. One-pot synthesis of quinaldine derivatives by using microwave ...

    Indian Academy of Sciences (India)

    Abstract. A convenient and efficient procedure for synthesis of quinaldine derivatives has been developed by a simple one-pot reaction of aniline derivatives and acetaldehyde on the surface of neutral alumina impregnated with hydrochloric acid under microwave irradiation without any solvent according to green chemistry.

  5. Microwave-assisted low temperature synthesis of sodium zirconium ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Microwave-assisted procedure for low temperature solid state synthesis of sodium zirconium phosphate (NZP), a material with the potential for immobilization and disposal of high level nuclear waste, was developed. Three selected fission products, namely, Cesium, Strontium and Tellurium were introduced ...

  6. Electroless Ni–P–ferrite composite coatings for microwave ...

    Indian Academy of Sciences (India)

    Abstract. Electroless, EL coating technique is one of the elegant ways of coating by controlling the temperature and pH of the coating bath in which there is no usage of electric current. It is estimated that the market for this chemistry will increase at a rate of about 15% per year. Use of microwave energy for synthesis of ...

  7. Microwave plasma deposition of diamond like carbon coatings

    Indian Academy of Sciences (India)

    Abstract. The promising applications of the microwave plasmas have been appearing in the fields of chemical processes and semiconductor manufacturing. Applications include surface deposition of all types including diamond/diamond like carbon (DLC) coatings, etching of semiconductors, promotion of organic reactions, ...

  8. Microwave-assisted one-pot synthesis of benzothiazole and ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 124; Issue 3 ... Abstract. Microwave-assisted synthesis of benzothiazole and benzoxazole libraries via PIFA promoted cyclocondensation of 2-aminothiophenols/2-aminophenols with aldehydes under one-pot condition in good to excellent yields was achieved. Twenty ...

  9. Two-dimensional microwave band-gap structures of different ...

    Indian Academy of Sciences (India)

    Abstract. We report the use of low dielectric constant materials to form two- dimensional microwave band-gap structures for achieving high gap-to-midgap ratio. The variable parameters chosen are the lattice spacing and the geometric structure. The se- lected geometries are square and triangular and the materials chosen ...

  10. Deprotection of oximes using urea nitrate under microwave irradiation

    Indian Academy of Sciences (India)

    Unknown

    Abstract. A new mild and efficient method for the cleavage of oximes to carbonyl compounds using readily available urea nitrate in acetonitrile–water (95 : 5), under ... Keywords. Deprotection; oximes; carbonyl compounds; urea nitrate; microwave irradiation. 1. Introduction. Oximes are readily prepared and stable1 and are.

  11. Measurement of high-power microwave pulse under intense ...

    Indian Academy of Sciences (India)

    Abstract. KALI-1000 pulse power system has been used to generate single pulse nanosecond duration high-power microwaves (HPM) from a virtual cathode oscillator. (VIRCATOR) device. HPM power measurements were carried out using a transmitting– receiving system in the presence of intense high frequency (a few ...

  12. Synthesis and microwave dielectric properties of Ca substituted ...

    Indian Academy of Sciences (India)

    Keywords. Patch antenna; theoretical density; phase; ceramics. Abstract. Microwave dielectric ceramics in Sr1-CaLa4Ti4.93Zr0.07O17 (0 ≤ ≤ 0.5) composition series were processed via a solid-state sintering rout. X-ray diffraction revealed single phase ceramics. Ca substitutions for Sr tuned f towards zero with ...

  13. Microwave assisted hydrolysis of aluminium metal and preparation ...

    Indian Academy of Sciences (India)

    Centre for Materials for Electronics Technology (C-MET), Department of Information Technology, Government of India, Athani PO, Thrissur 680 581, India. MS received 30 June 2009; revised 27 July 2009. Abstract. Phase pure boehmite particles were prepared by microwave assisted hydrolysis of aluminium sheets.

  14. Microwave-assisted Chemical Transformations

    Science.gov (United States)

    In recent years, there has been a considerable interest in developing sustainable chemistries utilizing green chemistry principles. Since the first published report in 1986 by Gedye and Giguere on microwave assisted synthesis in household microwave ovens, the use of microwaves as...

  15. PHYSICS OF MICROWAVES IN MICROSCOPY

    NARCIS (Netherlands)

    KOK, LP

    1990-01-01

    Microwave technology can help in the preparation of samples for microscopy in many different ways. This paper discusses the physics of microwaves. It gives the theoretical background to understand the practical procedures. Some peculiarities in the optics of microwaves are pointed out. Diffusion

  16. Method development for the determination of calcium, copper, magnesium, manganese, iron, potassium, phosphorus and zinc in different types of breads by microwave induced plasma-atomic emission spectrometry.

    Science.gov (United States)

    Ozbek, Nil; Akman, Suleyman

    2016-06-01

    A novel method was developed for the determination of calcium, magnesium, potassium, iron, copper, zinc, and manganese and phosphorous in various kinds of breads samples sold in Turkey by microwave plasma-atomic emission spectrometry (MIP-AES). Breads were dried at 100 °C for one day, ground thoroughly and then digested using nitric acid/hydrogen per oxide (3:1). The analytes in certified reference wheat flour and maize flour samples were determined in the uncertainty limits of the certified values as well as the analytes added to the mixture of ground bread and acid mixture prior to digestion were recovered quantitatively (>90%). Therefore, all determinations were made by linear calibration technique using aqueous standards. The LOD values for Ca, Cu, Fe, K, Mg, Mn, P and Zn were 13.1, 0.28, 4.47, 118, 1.10, 0.41, 7550 and 3.00 ng mL(-1), respectively. No spectral interference was detected at the working wavelengths of the analytes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. First-Row-Transition Ion Metals(II-EDTA Functionalized Magnetic Nanoparticles as Catalysts for Solvent-Free Microwave-Induced Oxidation of Alcohols

    Directory of Open Access Journals (Sweden)

    Nuno M. R. Martins

    2017-11-01

    Full Text Available A series of first-row transition-metals combined with ethylenediamine tetraacetic acid (EDTA, as metal-based N,O-chelating ligands, at the surface of ferrite magnetic nanoparticles (MNPs was prepared by a co-precipitation method. Those EDTA functionalized MNPs with general formula Fe3O4@EDTA-M2+ [M = Mn2+ (1, Fe2+ (2, Co2+ (3, Ni2+ (4, Cu2+ (5 or Zn2+ (6] were characterized by FTIR (Fourier Transform Infrared spectroscopy, powder XRD (X-ray Diffraction, SEM (Scanning Electron Microscope, EDS (Energy Dispersive Spectrometer, VSM (Vibrating Sample Magnetometer and TGA (Thermal Gravity Analysis. The application of the magnetic NPs towards the microwave-assisted oxidation of several alcohol substrates in a solvent-free medium was evaluated. The influence of reaction parameters such as temperature, time, type of oxidant, and presence of organic radicals was investigated. This study demonstrates that these MNPs can act as efficient catalysts for the conversion of alcohols to the corresponding ketones or aldehydes with high selectivity and yields up to 99% after 2 h of reaction at 110 °C using t-BuOOH as oxidant. Moreover, they have the advantage of being magnetically recoverable catalysts that can be easily recycled in following runs.

  18. Fundamentals of microwave photonics

    CERN Document Server

    Urick, V J; McKinney , Jason D

    2015-01-01

    A comprehensive resource to designing andconstructing analog photonic links capable of high RFperformanceFundamentals of Microwave Photonics provides acomprehensive description of analog optical links from basicprinciples to applications.  The book is organized into fourparts. The first begins with a historical perspective of microwavephotonics, listing the advantages of fiber optic links anddelineating analog vs. digital links. The second section coversbasic principles associated with microwave photonics in both the RFand optical domains.  The third focuses on analog modulationformats-starti

  19. Microwave Assisted Drug Delivery

    DEFF Research Database (Denmark)

    Jónasson, Sævar Þór; Zhurbenko, Vitaliy; Johansen, Tom Keinicke

    2014-01-01

    In this work, the microwave radiation is adopted for remote activation of pharmaceutical drug capsules inside the human body in order to release drugs at a pre-determined time and location. An array of controllable transmitting sources is used to produce a constructive interference at a certain...... focus point inside the body, where the drugs are then released from the specially designed capsules. An experimental setup for microwave activation has been developed and tested on a body phantom that emulates the human torso. A design of sensitive receiving structures for integration with a drug...

  20. Microwave circulator design

    CERN Document Server

    Linkhart, Douglas K

    2014-01-01

    Circulator design has advanced significantly since the first edition of this book was published 25 years ago. The objective of this second edition is to present theory, information, and design procedures that will enable microwave engineers and technicians to design and build circulators successfully. This resource contains a discussion of the various units used in the circulator design computations, as well as covers the theory of operation. This book presents numerous applications, giving microwave engineers new ideas about how to solve problems using circulators. Design examples are provided, which demonstrate how to apply the information to real-world design tasks.

  1. EDITORIAL: Microwave Moisture Measurements

    Science.gov (United States)

    Kaatze, Udo; Kupfer, Klaus; Hübner, Christof

    2007-04-01

    Microwave moisture measurements refer to a methodology by which the water content of materials is non-invasively determined using electromagnetic fields of radio and microwave frequencies. Being the omnipresent liquid on our planet, water occurs as a component in most materials and often exercises a significant influence on their properties. Precise measurements of the water content are thus extremely useful in pure sciences, particularly in biochemistry and biophysics. They are likewise important in many agricultural, technical and industrial fields. Applications are broad and diverse, and include the quality assessment of foodstuffs, the determination of water content in paper, cardboard and textile production, the monitoring of moisture in sands, gravels, soils and constructions, as well as the measurement of water admixtures to coal and crude oil in reservoirs and in pipelines. Microwave moisture measurements and evaluations require insights in various disciplines, such as materials science, dielectrics, the physical chemistry of water, electrodynamics and microwave techniques. The cooperation of experts from the different fields of science is thus necessary for the efficient development of this complex discipline. In order to advance cooperation the Workshop on Electromagnetic Wave Interaction with Water and Moist Substances was held in 1993 in Atlanta. It initiated a series of international conferences, of which the last one was held in 2005 in Weimar. The meeting brought together 130 scientists and engineers from all over the world. This special issue presents a collection of some selected papers that were given at the event. The papers cover most topics of the conference, featuring dielectric properties of aqueous materials, electromagnetic wave interactions, measurement methods and sensors, and various applications. The special issue is dedicated to Dr Andrzej W Kraszewski, who died in July 2006 after a distinguished career of 48 years in the research of

  2. Grounding abstractness: Abstract concepts and the activation of the mouth

    Directory of Open Access Journals (Sweden)

    Anna M Borghi

    2016-10-01

    Full Text Available One key issue for theories of cognition is how abstract concepts, such as freedom, are represented. According to the WAT (Words As social Tools proposal, abstract concepts activate both sensorimotor and linguistic/social information, and their acquisition modality involves the linguistic experience more than the acquisition of concrete concepts. We report an experiment in which participants were presented with abstract and concrete definitions followed by concrete and abstract target-words. When the definition and the word matched, participants were required to press a key, either with the hand or with the mouth. Response times and accuracy were recorded. As predicted, we found that abstract definitions and abstract words yielded slower responses and more errors compared to concrete definitions and concrete words. More crucially, there was an interaction between the target-words and the effector used to respond (hand, mouth. While responses with the mouth were overall slower, the advantage of the hand over the mouth responses was more marked with concrete than with abstract concepts. The results are in keeping with grounded and embodied theories of cognition and support the WAT proposal, according to which abstract concepts evoke linguistic-social information, hence activate the mouth. The mechanisms underlying the mouth activation with abstract concepts (re-enactment of acquisition experience, or re-explanation of the word meaning, possibly through inner talk are discussed. To our knowledge this is the first behavioral study demonstrating with real words that the advantage of the hand over the mouth is more marked with concrete than with abstract concepts, likely because of the activation of linguistic information with abstract concepts.

  3. Grounding Abstractness: Abstract Concepts and the Activation of the Mouth.

    Science.gov (United States)

    Borghi, Anna M; Zarcone, Edoardo

    2016-01-01

    One key issue for theories of cognition is how abstract concepts, such as freedom, are represented. According to the WAT (Words As social Tools) proposal, abstract concepts activate both sensorimotor and linguistic/social information, and their acquisition modality involves the linguistic experience more than the acquisition of concrete concepts. We report an experiment in which participants were presented with abstract and concrete definitions followed by concrete and abstract target-words. When the definition and the word matched, participants were required to press a key, either with the hand or with the mouth. Response times and accuracy were recorded. As predicted, we found that abstract definitions and abstract words yielded slower responses and more errors compared to concrete definitions and concrete words. More crucially, there was an interaction between the target-words and the effector used to respond (hand, mouth). While responses with the mouth were overall slower, the advantage of the hand over the mouth responses was more marked with concrete than with abstract concepts. The results are in keeping with grounded and embodied theories of cognition and support the WAT proposal, according to which abstract concepts evoke linguistic-social information, hence activate the mouth. The mechanisms underlying the mouth activation with abstract concepts (re-enactment of acquisition experience, or re-explanation of the word meaning, possibly through inner talk) are discussed. To our knowledge this is the first behavioral study demonstrating with real words that the advantage of the hand over the mouth is more marked with concrete than with abstract concepts, likely because of the activation of linguistic information with abstract concepts.

  4. Microplasmas ignited and sustained by microwaves

    Science.gov (United States)

    Hopwood, Jeffrey; Hoskinson, Alan R.; Gregório, José

    2014-12-01

    The challenges and benefits of microwave-induced microdischarges are reviewed. Transmission lines, resonators and surface wave launchers may be used for coupling microwave power to very small plasmas. Fortunately, microplasmas are typically much smaller than the wavelength of microwaves, and the electromagnetic problem may be treated electrostatically within the plasma. It is possible to trap electrons within small discharge gaps if the amplitude of electron oscillation is smaller than the plasma size. Typically occurring above 0.3 GHz, this condition results in lower breakdown fields than are required by direct current or radio frequency systems. Trapping of electrons also decreases the electrode potential to only tens of volts and makes the plasma density invariant in time. The steady-state microplasma produces electron densities of up to 1015 cm-3 in argon but the electrons are not in equilibrium with the low gas temperatures (500-1000 K). Microwave discharges are compared with other forms of microplasma and guidelines for device selection are recommended. Scale-up of microplasmas using array concepts are presented followed by some exciting new applications.

  5. Microplasmas ignited and sustained by microwaves

    International Nuclear Information System (INIS)

    Hopwood, Jeffrey; Hoskinson, Alan R; Gregório, José

    2014-01-01

    The challenges and benefits of microwave-induced microdischarges are reviewed. Transmission lines, resonators and surface wave launchers may be used for coupling microwave power to very small plasmas. Fortunately, microplasmas are typically much smaller than the wavelength of microwaves, and the electromagnetic problem may be treated electrostatically within the plasma. It is possible to trap electrons within small discharge gaps if the amplitude of electron oscillation is smaller than the plasma size. Typically occurring above 0.3 GHz, this condition results in lower breakdown fields than are required by direct current or radio frequency systems. Trapping of electrons also decreases the electrode potential to only tens of volts and makes the plasma density invariant in time. The steady-state microplasma produces electron densities of up to 10 15  cm −3 in argon but the electrons are not in equilibrium with the low gas temperatures (500–1000 K). Microwave discharges are compared with other forms of microplasma and guidelines for device selection are recommended. Scale-up of microplasmas using array concepts are presented followed by some exciting new applications. (paper)

  6. Mechanical Engineering Department technical abstracts

    International Nuclear Information System (INIS)

    Denney, R.M.

    1982-01-01

    The Mechanical Engineering Department publishes listings of technical abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). Overall information about current activities of each of the Department's seven divisions precedes the technical abstracts

  7. Mechanical Engineering Department technical abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Denney, R.M. (ed.)

    1982-07-01

    The Mechanical Engineering Department publishes listings of technical abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). Overall information about current activities of each of the Department's seven divisions precedes the technical abstracts.

  8. Logical Full Abstraction and PCF

    OpenAIRE

    Longley, John R; Plotkin, Gordon

    2000-01-01

    We introduce the concept of logical full abstraction, generalising the usual equational notion. We consider the language PCF and two extensions with “parallel” operations. The main result is that, for standard interpretations, logical full abstraction is equivalent to equational full abstraction together with universality; the proof involves constructing enumeration operators. We also consider restrictions on logical complexity and on the level of types.

  9. Properties of microwave plasma torch operating at a low pressure

    International Nuclear Information System (INIS)

    Cho, Soon C.; Uhm, Han S.; Hong, Yong C.; Kim, Jae H.

    2008-01-01

    A microwave plasma torch system is attached to a low-pressure chamber in this study. The electric field induced in a quartz discharge tube by microwave radiation breaks down the gas at a sufficiently low pressure, igniting the plasma, which is continuously sustained by the microwave radiation. The plasma profile at a very low pressure is shown to be asymmetric with higher density on the incoming side of the microwaves. The gas temperature at the bright spot of the torch plasma measured via the optical emission from hydroxide radicals is shown to increase drastically upon high-pressure operation as the microwave power increases. The electron density at the torch flame is measured by recording the Stark broadening of the hydrogen Balmer beta line. The plasma density increases as the microwave power increases. The typical argon plasma density of a plasma torch powered at 500 W under a pressure of 150 Torr is on the order of 10 14 /cm 3 . The electron temperature in the argon torch plasma was estimated to be 1.5 eV, thereby effectively exciting the molecules in the torch gas. Disintegration of nitrogen fluoride (NF 3 ) indicates that a microwave plasma torch operating at a low pressure can efficiently generate an abundant amount of chemical radicals.

  10. Study of microwave emission from a dense plasma focus

    International Nuclear Information System (INIS)

    Gerdin, G.; Venneri, F.; Tanisi, M.

    1985-01-01

    Microwave emission was detected in a 12.5 kJ dense plasma focus, using microwave horns and detectors placed in various locations outside the device. The results show that the parallel plates connecting the focus to its capacitor banks act as antennas and transmission lines, rather than wave guides. Subsequent measurements were performed with a microwave detector (R-band) attached to the focus anode, directly looking into the coaxial gun region, allowing to restrict the microwave emitting region to the muzzle end of the focus. The microwave frequency spectrum, determined with a time of flight detection system, strongly suggests the lower hybrid instability as the driving mechanism of the emissions. Comparing the time sequence of the emissions with those of other observable phenomena in the focus, a model was developed, to explain the possible relationship between the generation of microwave radiation and turbulence induced resistivity in the focus pinch. According to the model, microwaves and enhanced resistivity are caused by current driven instabilities occurring in the current sheath produced at the outer boundary of the pinch during the initial compression phase. Comparisons of the model predictions with observed experimental results are presented, including time resolved measurements of the pinch resistivity

  11. Microwave thermotherapy for benign prostatic hyperplasia.

    Science.gov (United States)

    Hoffman, Richard M; Monga, Manoj; Elliott, Sean P; Macdonald, Roderick; Langsjoen, Jens; Tacklind, James; Wilt, Timothy J

    2012-09-12

    Transurethral resection of the prostate (TURP) has been the gold-standard treatment for alleviating urinary symptoms and improving urinary flow in men with symptomatic benign prostatic hyperplasia (BPH). However, the morbidity of TURP approaches 20%, and less invasive techniques have been developed for treating BPH. Preliminary data suggest that microwave thermotherapy, which delivers microwave energy to produce coagulation necrosis in prostatic tissue, is a safe, effective treatment for BPH. To assess the therapeutic efficacy and safety of microwave thermotherapy techniques for treating men with symptomatic benign prostatic obstruction. Randomized controlled trials were identified from The Cochrane Library, MEDLINE, EMBASE, bibliographies of retrieved articles, reviews, technical reports, and by contacting relevant expert trialists and microwave manufacturers. All randomized controlled trials evaluating transurethral microwave thermotherapy (TUMT) for men with symptomatic BPH were eligible for this review. Comparison groups could include transurethral resection of the prostate, minimally invasive prostatectomy techniques, sham thermotherapy procedures, and medications. Outcome measures included urinary symptoms, urinary function, prostate volume, mortality, morbidity, and retreatment. Two review authors independently identified potentially relevant abstracts and then assessed the full papers for inclusion. Two review authors independently abstracted study design, baseline characteristics, and outcomes data and assessed methodological quality using a standard form. We attempted to obtain missing data from authors or sponsors, or both. In this update, we identified no new randomized comparisons of TUMT that provided evaluable effectiveness data. Fifteen studies involving 1585 patients met the inclusion criteria, including six comparisons of microwave thermotherapy with TURP, eight comparisons with sham thermotherapy procedures, and one comparison with an alpha

  12. Abstract

    African Journals Online (AJOL)

    ­E¢b

    direction, which is believed to lead to improved social life and welfare. This means that Ethiopian trade and economic ... holding better market share and customer satisfaction in their products and services. In addition, in both ...... 1995. Dominant Values and Parenting. Styles: Major Limiting Factors on the Development of.

  13. ABSTRACT

    African Journals Online (AJOL)

    their effective participation under different socio- ecological constraints (IDRC, 1993;Takyiwa, 1998;. Kinikanwo, 2000; Isiugo-Abanike, 1994; UNO, 1989). The general issue here is to estimate the extent of female participation in ruminant livestock operations with a view to establishing if stereotyping such operations along.

  14. Abstract

    African Journals Online (AJOL)

    feasible and sustainable options. ... strategies, specific to the benefits of exclusive breastfeeding as a mechanism to reduce the risk of HIV transmission is urgently needed ... Joyce Beatrice Ballidawa is a lecturer in the Department of Behavioural Sciences at Moi University School of Medicine, Eldoret, a position she has held.

  15. Abstracts

    International Nuclear Information System (INIS)

    2013-01-01

    The power point presentation is about: danger identification, caracterization, evaluation exposition, risk (CAC, 1997; FAO, 2007), European food safety authority, foodrisk organization, pathogens risk ranking, risk reduction, gubernamental responsability

  16. ABSTRACT

    Indian Academy of Sciences (India)

    Efforts have also been successfully made to include the study of rock art in the school/ college curriculum so as to help develop awareness amongst the students and general public about the need to preserve this cultural heritage for the posterity and also to highlight its importance in tourism industry. rock art and their ...

  17. ABSTRACT

    Indian Academy of Sciences (India)

    ... school/ college curriculum so as to help develop awareness amongst the students and general public about the need to preserve this cultural heritage for the posterity and also to highlight its importance in tourism industry. rock art and their chronological sequences to more applied aspects like scientific methods of dating ...

  18. Abstract

    African Journals Online (AJOL)

    Francis

    Ficus species. Journal of Ethnopharmacology 41: 71-76. Nadkarni KM (1976) Indian Materia Medica. Third edition, Vol I. Popular Prakhasan, Bombay. NCCLS (National Committee for Clinical Laboratory Standards) (1999). Performance standards for antimicrobial susceptibility testing. 9th International Supplement M100- ...

  19. Abstract

    African Journals Online (AJOL)

    Getachew

    realistic distribution of no-show data in modeling the cost function was considered using data collected from the .... the paper models the cost function based on a realistic probability distributions based on the historical data is a .... Plot of Revenue generated vs. overbooking for two class case (at $500. Compensation Cost ...

  20. Abstract

    African Journals Online (AJOL)

    Dr Osondu

    2011-10-26

    Oct 26, 2011 ... Keywords: Municipal solid waste; Geographic information system; waste bin; optimal location; developing city. Introduction. Over the years, the spatial organization and existing infrastructure of cities in developing countries pose challenges for sustainable solid waste management programs. Much of the ...

  1. Abstract

    African Journals Online (AJOL)

    ATTAMAH C. O

    Differences in Climate Change Effects and Adaptation Strategies between Male and Female Livestock Entrepreneurs in ... differed from females in the adaptation strategies used in combating climate change and also on their view on ..... also make use of the same farm road whether in good or bad shape. This is in line with.

  2. Abstract

    African Journals Online (AJOL)

    viral activity has been observed for halofantrine, amodiaquine and mepacrine.” The clinical significance of these findings is uncertain“"”-. There is some evidence that HIV protease inhibitors may alter disease outcomes of colnfected patients.

  3. Abstract

    African Journals Online (AJOL)

    was to determine how the natural aerial connec- teracting worker ants from adjacent trees and tions affected'the viability of colonies Oro!. , observing whether fighting took~iplace :(Yar~ra,. IQffginoda in the tree crowns, in the presence of, 1992). Ants of different colonies fight aggres- inimical ants,P" megacephala, 'on the ...

  4. abstract

    Directory of Open Access Journals (Sweden)

    . user

    2016-02-01

    Full Text Available Introduction: One of the microbiological preparations used for this study was Effective Microorganisms (EM, being a commercial mixture of photosynthesizing bacteria, Actinomycetes, lactic acid bacteria, yeasts and fermenting fungi. The microbiological composition of the EM concentrateincludesStreptomyces albus, Propioni bacterium freudenreichil, Streptococcus lactis, Aspergillus oryzae, Mucor hiemalis, Saccharomycescerevisiae and Candida utilis. Moreover, EM also contains an unspecified amount of Lactobacillus sp. Rhodo pseudomonas sp. and Streptomyces griseus. Effective Microorganisms have a positive effect on the decomposition of organic matter, limiting putrefaction, increasing nitrogen content in the root medium of plants, phosphorus, improving soil fertility and as a result contributing to the growth and development of the root systems of plants. Selection of almond vegetative rootstocks for water stress tolerance is important for almond crop production in arid and semi-arid regions. The study of the eco-morphological characteristics that determine the success of a rootstock in a particular environment is a powerful tool for both agricultural management and breeding purposes. The aim of this work was to select the new rootstocks for water shortage tolerance, impact of water stress as well as Effective Microorganism (EM on morphological characteristics of almond rootstocks. Materials and Methods: In order to select the new rootstocks for water shortage tolerance, impact of water stress as well as EMonmorphologicalcharacteristics of almondrootstocks were studiedin thedepartment ofHorticulture, Ferdowsi University of Mashhad, in 2011-2012. The experiment was carried out with four replications in a completely random blockdesign to study the effects of two concentrations of EM (0 and 1%, three irrigation levels (normal irrigation 100%-control-and irrigation after depletion of 33 and 66% of available water, and four almond rootstocks including GF677 and selected natural hybrid of peach × almond (H1and H2, and almond vegetative rootstock (local control.In this study,EMtreatments for 60 days before stress treatments were applied so that in each irrigation, EM solution to a concentration of one percent was given to half of the experiment pots. Other pots were irrigated equally with normal water. Stress levels were applied from July as follow: full irrigation, watering after unloading 33% and 66% soil moisture availability. In order to evaluate the performance, seedling survival, plant growth, number of leaves, leaf area, root fresh and dry weight and leaves and root length were measured. Results and Discussion: Analysis of variance showed that between rootstock levels across all treatments were significantly differences at 0.01 level of probability. Comparison of means showed that the highest fresh and dry weight and leaf are awere observed forGF677and H1.Rootstockannualgrowth rate was also different. Most of the growth was related to the H1 Rootstocks. Thes urvival ratewas significantly different from the Rootstocks ofGF677,andH1showedthe highestpercentage of survival. The degree of adaptation to drought in varieties of almonds is different. The results showed that changes ingrowthparametersinGF677and H1were observed less often than other rootstocks. Because of strong roots,GF677and H1continue to attract more minerals under stress conditions. Analysis of variance showed that the between irrigation levels for all treatments were significantly different at 0.01 level of probability. Comparison of means showed that among the study traits, the highest amount was obtained from complete irrigation, while irrigationat66 percenthad the least amount. Water stress may directly affect photosyn thesis, through leaf photochemicalprocessorindirectly,byclosing stomata, reducingleaf area and growth. The results showed that the levels of(EM on the leaf surface, leaf number, annual growth, root dry weight and volume were significantly different (p

  5. ABSTRACT

    African Journals Online (AJOL)

    BSN

    The preservative effect of CO\\\\'pea pods. seeds, husk. and water and ethanol extracts of the seeds and ... preservation of "kindirmo" with water and ethanol extracts of seeds and husk of. CO\\\\'J)Ca for most of the ... Perhaps same may apply in the area of preservatives: plant products may be safer and biologically friendlier.

  6. Abstract

    Indian Academy of Sciences (India)

    2017-03-10

    Mar 10, 2017 ... TaqMan allelic discrimination assay. .... women). All patients fulfilled the 1987 American College of Rheumatology criteria for RA. (Arnett et al. 1988). A rheumatology university fellow reviewed all clinical data. ... The rs6457617 and rs13192471 were genotyped with a TaqMan 5' allelic discrimination.

  7. Abstracts

    International Nuclear Information System (INIS)

    1989-09-01

    The proceedings contain 106 papers of which 2 fall under the INIS Scope. One concerns seismic risk assessment at radioactive waste repositories in the U.S., the other concerns the possibility of predicting earthquakes from changes in radon 222 levels in selected ground water springs of northern Italy. (M.D.)

  8. abstract

    Directory of Open Access Journals (Sweden)

    abstract abstract

    2016-07-01

    Full Text Available Introduction: Strawberry (fragaria×ananassa Duch. fruit characterized by short storage life, often estimated last less than one week even under optimum conditions at 8°C. The loss of fruit quality is often caused by gray mold (Botrytis cinerea that is the most frequent reported postharvest disease in strawberry during storage (6. In recent years, considerable attention has given to elimination of synthetic chemical and fungicides application and development of various alternative strategies for controlling fruit and vegetables diseases (2. One strategy is replacement of natural products with plant origin such as essential oil and methyl salicylate (MeSA. Essential oils are volatile, natural and complex compounds characterized by a strong odor formed by aromatic plants in form of secondary metabolites. In nature, essential similar oils that extract from lavender (Lavandula angustifolia play an important role in protection of the plants against pathogen incidence that can be replaced by synthetic fungicides (1, 4 and 14. MeSA is also a volatile natural compound synthesized from salicylic acid which has an important role in the plant defense-mechanism, as well as plant growth and development (5, 19 and 20. Therefore, the main objective of this research was to study the effects of MeSA and lavender essential oil (LEO on decay control caused by Botrytis cinerea as well as post-harvest quality indices of strawberry fruits during cold storage. Material and Methods: First, antifungal activity was studied by using a contact assay (in vitro, which produces hyphal growth inhibition. Briefly, potato dextrose agar (PDA plates were prepared using 8 cm diameter glass petri dishes and inhibitory percentage was determined. For in-vivo assessment of LEO and MeSA effects on Botrytis-caused fungal disease control, the experiment was conducted as factorial in completely randomized design (CRD with 3 replicates. The treatments were 3 concentration of LEO including 0, 500 and 1000 µl L-1 and 3 level of MeSA including 0, 0.1 and 0.2 mM. After treatment, the fruits were inoculated by Botrytis suspension and transferred to storage and quality parameters were evaluated after 7, 14 and 21 days. At each sampling time, disease incidence, weight loss, titratable acidity, pH, soluble solids content, vitamin C and antioxidant activity were measured. Results and Discussion: The results showed that both LEO and MeSA treatments had significant effects on inhibition of mycelium growth within in-vitro condition (p < 0.05. Inhibition rate of mycelium growth significantly improved by LEO and MeSA concentration increase of, (Table 1. At in-vivo assessment, diseases incidence of treated fruits with 500 µl L-1 LEO and 0.1 mM MeSA were 32% and 64% lower than untreated fruits, respectively (Fig. 1 and 2. During storage period, the percentage of infected fruits increased. In addition, LEO and MeSA treatments affected quality parameters of strawberry fruits including titratable acidity, soluble solids content, vitamin C and antioxidant activity. Treated fruits had a high content of soluble solids, vitamin C and antioxidant activity in comparison to untreated fruits (Table 3 and 4. Probably ascorbic acid decreased through fungal infection duo to cell wall break down during storage. Any factors such as essential oil and salicylate that inhibit fungal growth can help preserving vitamin C in stored products. High level of vitamin C and antioxidant activity was observed in treated fruits with 0.1 mM MeSA and 500 µl L-1 LEO. In controlling weight loss of fruits, 0.2 mM of MeSA and 500 µl L-1 of LEO had significant effects, although MeSA was more effective than LEO treatments, possibly due to elimination of respiration rates and fungi infection (Table 4. Therefore, LEO and MeSA with fungicide effects could be replaced with synthetic fungicides in controlling fungal diseases of strawberry and maintain fruits quality during storage. Conclusion: In conclusion, our results showed that LEO and MeSA treatments could be safe and used to prevent infection of strawberry during storage, although LEO was more effective than MeSA treatments. Concentration of 500 μl L-1 of LEO and 0.1 mM MeSA could control fungal infection of fruits during storage. Also, LEO and MeSA treatments can extend shelf life for over the minimum period required to transit strawberries to foreign markets and without affecting quality, adversely. However, future studies are necessary to fully understand the mechanisms by which LEO and MeSA treatments may act as a fungicide and increase their postharvest life.

  9. Abstract

    Indian Academy of Sciences (India)

    This talk deals with the geometry of Banach spaces. A non-reflexive Banach space embeds canonically in its second dual and the process continues, giving raise to a strictly increasing chain of Banach spaces. A well known example of a geometric phenomenon that is preserved in this chain, is that of being (isometric) a ...

  10. Abstract

    African Journals Online (AJOL)

    PROF. O. E. OSUAGWU

    This software template is also of immense benefits to students of different ... connection, there is the potential to track learner's action in a ..... intelligence. This software will be a direct application of artificial intelligence to develop a special authoring system for e- learning that will have the ability to learn. Intelligent authoring ...

  11. Abstract

    DEFF Research Database (Denmark)

    Tafdrup, Oliver

    2013-01-01

    Udgivet som en del af Tidskrifts specialudgivelse om Adorno. http://tidskrift.dk/data/50/Aforismesamling.pdf......Udgivet som en del af Tidskrifts specialudgivelse om Adorno. http://tidskrift.dk/data/50/Aforismesamling.pdf...

  12. Abstract

    African Journals Online (AJOL)

    Maru Shete

    of voice, power and representation. To avert this situation, poor women in the research area require equal participation in resources sharing and power of decision making, better employment, housing, education, health care and other opportunities for social service opportunities through savings and credit cooperatives.

  13. ABSTRACT

    African Journals Online (AJOL)

    Chylous leakage is an unusual complication following anterior spinal surgery. This leakage can occur as a result of traumatic injury to the thoracic duct, the cisterna chyli, or the retroperitoneal lymphatic vessels. We report a case of a 56 year old female with thoracic spine disc prolapses with cord compression. She.

  14. Abstract

    Indian Academy of Sciences (India)

    2017-03-10

    Mar 10, 2017 ... Significant p-values were corrected (pc) by the number of alleles tested or subgroups analysed according to Bonferroni's ... LD in healthy controls between both rs13192471/rs6457617 with a value of D'=0.99 and ..... Radstake T.R., Gorlova O., Rueda B., Martin J.E., Alizadeh B.Z., Palomino-Morales R. et al.

  15. ABSTRACT

    African Journals Online (AJOL)

    -. 1111'. Cl". SO41-. (11-. $0}-. C1; sof-. SW' s-j'. (11; so}. New-_ Blank 'spa§cS imply rhelal levels below cleteczim. ,1 z,m1:> .Qu11>»»»: mtalive analysis _ . 1 mined for individual 1ni11cral. §_'r['§>f:é€lY.l.'.l.fi;'u'- we Table l 006%. 1 ii'!

  16. Abstract

    African Journals Online (AJOL)

    Getachew

    request made by a customer for a reservation of a certain class at time T. Although dynamic .... to both customer reaction upon denied boarding and profit loss. .... Sabanci University. http://www.optimization- online.org. Bailey, J. 2007. Bumped fliers and no plan B. The New York Times. Beckman, M.J & Bobkoski, F. 1985.

  17. ABSTRACT

    Directory of Open Access Journals (Sweden)

    Michelle de Stefano Sabino

    2011-12-01

    Full Text Available This paper aims to describe and to analyze the integration observed in the Sintonia project with respect to the comparison of project management processes to the model of the Stage-Gate ®. The literature addresses these issues conceptually, but lack an alignment between them that is evident in practice. As a method was used single case study. The report is as if the Sintonia project, developed by PRODESP - Data Processing Company of São Paulo. The results show the integration of project management processes with the Stage-Gate model developed during the project life cycle. The formalization of the project was defined in stages in which allowed the exploitation of economies of repetition and recombination to the development of new projects. This study contributes to the technical vision in dealing with the integration of project management processes. It was concluded that this system represents an attractive way, in terms of creating economic value and technological innovation for the organization.

  18. Abstract

    African Journals Online (AJOL)

    UDS-CAPTURED

    The high cost of delivering financial services to small and widely dispersed customers as well as difficult financial terrain in rural settings characterized by high covariant risks, missing markets for risk management instruments and ... Improving the extent of access to credit for low income households is a vital part of any rural ...

  19. Abstract

    African Journals Online (AJOL)

    dell

    the curriculum in higher education. In a similar way, major advances in biological, health sciences, social sciences, physical and life sciences, business and economics, and technology lead to revision of courses in the field. In line, with the everlasting explosion of knowledge and increasing sophistication of technology ...

  20. ABSTRACT

    African Journals Online (AJOL)

    production alone cannot provide the animal protein needs of about 100 million Nigerians. This, therefore calls for ... Fish contributes about 12 percent of the total animal protein supply of the World population (Borgstorm, ..... motivation for extension personnel (7.5%), inadequate transport facilities (5.5%), absence of strong ...

  1. Abstracts

    OpenAIRE

    Revista, Innovar

    2011-01-01

    New approaches towards Efficiency, Productivity and Quality in Management Theory / New approaches towards Efficiency, Productivity and Quality in Management Theory / The new paradigm regarding Science and Management Theory / Game Theory as applied to Administration / A Systemic approach to Territorial Diagnosis /  A prolile 0f Technological Capacity in the Graphical Art, Printing and Publishing Industry / Colombian Industrialisation: a Heterodox Vision /Determinant factors in environmental po...

  2. Abstract

    African Journals Online (AJOL)

    Implementing this collaborative e-learning environment on a Linux thin-client system makes it possible for this environment to be available in most schools and companies because the Linux thin-clients are less expensive than other conventional computing systems. Developing a. Collaborative E-Learning Environment on ...

  3. abstract

    African Journals Online (AJOL)

    communication and institutions activities in removing constraints which impede the acceptance and continued usage .... With farmers' feedback, scientists cannot misinterpret a problem or attribute wrong causes to it. ..... Protection and Environmental Management, University of lbadan,. Ibadan. Ashby, J. (1990): Small-farmer ...

  4. Abstract ~. ,

    African Journals Online (AJOL)

    Governmenf to educate dairy farmers, milli vendors and the consume~s on the importance of producing, selling and consuming respectively un-adulterated milk. Key words: Milk, water adulteration, Morogoro Municipality. Introduction. Total annual milk production in Tanzania is estimated to be at 724,000 metric tons (F AO,.

  5. Microwave stability at transition

    International Nuclear Information System (INIS)

    Holt, J.A.; Colestock, P.L.

    1995-05-01

    The question of microwave stability at transition is revisited using a Vlasov approach retaining higher order terms in the particle dynamics near the transition energy. A dispersion relation is derived which can be solved numerically for the complex frequency in terms of the longitudinal impedance and other beam parameters. Stability near transition is examined and compared with simulation results

  6. Nonlinear Microwave Optomechanics

    NARCIS (Netherlands)

    Shevchuk, O.

    2017-01-01

    The nonlinearity is essential for creation of non-classical states of the cavity or mechanical resonator such as squeezed or cat states. A microwave cavity can be made nonlinear by, for instance, adding Josephson junctions. The mechanical resonator is inherently nonlinear. The radiation pressure

  7. Leakage of Microwave Ovens

    Science.gov (United States)

    Abdul-Razzaq, W.; Bushey, R.; Winn, G.

    2011-01-01

    Physics is essential for students who want to succeed in science and engineering. Excitement and interest in the content matter contribute to enhancing this success. We have developed a laboratory experiment that takes advantage of microwave ovens to demonstrate important physical concepts and increase interest in physics. This experiment…

  8. Commercial microwave space power

    International Nuclear Information System (INIS)

    Siambis, J.; Gregorwich, W.; Walmsley, S.; Shockey, K.; Chang, K.

    1991-01-01

    This paper reports on central commercial space power, generating power via large scale solar arrays, and distributing power to satellites via docking, tethering or beamed power such as microwave or laser beams, that is being investigated as a potentially advantageous alternative to present day technology where each satellite carries its own power generating capability. The cost, size and weight for electrical power service, together with overall mission requirements and flexibility are the principal selection criteria, with the case of standard solar array panels based on the satellite, as the reference point. This paper presents and investigates a current technology design point for beamed microwave commercial space power. The design point requires that 25 kW be delivered to the user load with 30% overall system efficiency. The key elements of the design point are: An efficient rectenna at the user end; a high gain, low beam width, efficient antenna at the central space power station end, a reliable and efficient cw microwave tube. Design trades to optimize the proposed near term design point and to explore characteristics of future systems were performed. Future development for making the beamed microwave space power approach more competitive against docking and tethering are discussed

  9. The microwave heating mechanism of N-(4-methoxybenzyliden)-4-butylaniline in liquid crystalline and isotropic phases as determined using in situ microwave irradiation NMR spectroscopy.

    Science.gov (United States)

    Tasei, Yugo; Tanigawa, Fumikazu; Kawamura, Izuru; Fujito, Teruaki; Sato, Motoyasu; Naito, Akira

    2015-04-14

    Microwave heating effects are widely used in the acceleration of organic, polymerization and enzymatic reactions. These effects are primarily caused by the local heating induced by microwave irradiation. However, the detailed molecular mechanisms associated with microwave heating effects on the chemical reactions are not yet well understood. This study investigated the microwave heating effect of N-(4-methoxybenzylidene)-4-butylaniline (MBBA) in liquid crystalline and isotropic phases using in situ microwave irradiation nuclear magnetic resonance (NMR) spectroscopy, by obtaining (1)H NMR spectra of MBBA under microwave irradiation. When heated simply using the temperature control unit of the NMR instrument, the liquid crystalline MBBA was converted to the isotropic phase exactly at its phase transition temperature (Tc) of 41 °C. The application of microwave irradiation at 130 W for 90 s while maintaining the instrument temperature at 20 °C generated a small amount of isotropic phase within the bulk liquid crystal. The sample temperature of the liquid crystalline state obtained during microwave irradiation was estimated to be 35 °C by assessing the linewidths of the (1)H NMR spectrum. This partial transition to the isotropic phase can be attributed to a non-equilibrium local heating state induced by the microwave irradiation. The application of microwave at 195 W for 5 min to isotropic MBBA while maintaining an instrument temperature of 50 °C raised the sample temperature to 160 °C. In this study, the MBBA temperature during microwave irradiation was estimated by measuring the temperature dependent chemical shifts of individual protons in the sample, and the different protons were found to indicate significantly different temperatures in the molecule. These results suggest that microwave heating polarizes bonds in polar functional groups, and this effect may partly explain the attendant acceleration of organic reactions.

  10. Modal abstractions of concurrent behavior

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nanz, Sebastian; Nielson, Hanne Riis

    2011-01-01

    We present an effective algorithm for the automatic construction of finite modal transition systems as abstractions of potentially infinite concurrent processes. Modal transition systems are recognized as valuable abstractions for model checking because they allow for the validation as well as re...

  11. Pattern-Based Graph Abstraction

    NARCIS (Netherlands)

    Rensink, Arend; Zambon, Eduardo; Ehrig, H; Engels, G.; Kreowski, H.J.; Rozenberg, G.

    We present a new abstraction technique for the exploration of graph transformation systems with infinite state spaces. This technique is based on patterns, simple graphs describing structures of interest that should be preserved by the abstraction. Patterns are collected into pattern graphs, layered

  12. Abstraction by Set-Membership

    DEFF Research Database (Denmark)

    Mödersheim, Sebastian Alexander

    2010-01-01

    that the set of true facts does not monotonically grow with the transitions. We extend the scope of these over-approximation methods by defining a new way of abstraction that can handle such databases, and we formally prove that the abstraction is sound. We realize a translator from a convenient specification...

  13. Abstract concepts in grounded cognition

    NARCIS (Netherlands)

    Lakens, D.

    2010-01-01

    When people think about highly abstract concepts, they draw upon concrete experiences to structure their thoughts. For example, black knights in fairytales are evil, and knights in shining armor are good. The sensory experiences black and white are used to represent the abstract concepts of good and

  14. Magnetic nanoparticles for tunable microwave metamaterials

    KAUST Repository

    Noginova, Natalia

    2012-09-24

    Commonly, metamaterials are electrically engineered systems with optimized spatial arrangement of subwavelength sized metal and dielectric components. We explore alternative methods based on use of magnetic inclusions, such as magnetic nanoparticles, which can allow permeability of a composite to be tuned from negative to positive at the range of magnetic resonance. To better understand effects of particle size and magnetization dynamics, we performed electron magnetic resonance study on several varieties of magnetic nanoparticles and determined potential of nanoparticle use as building blocks for tunable microwave metamaterials. © (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  15. Technical abstracts: Mechanical engineering, 1990

    International Nuclear Information System (INIS)

    Broesius, J.Y.

    1991-01-01

    This document is a compilation of the published, unclassified abstracts produced by mechanical engineers at Lawrence Livermore National Laboratory (LLNL) during the calendar year 1990. Many abstracts summarize work completed and published in report form. These are UCRL-JC series documents, which include the full text of articles to be published in journals and of papers to be presented at meetings, and UCID reports, which are informal documents. Not all UCIDs contain abstracts: short summaries were generated when abstracts were not included. Technical Abstracts also provides descriptions of those documents assigned to the UCRL-MI (miscellaneous) category. These are generally viewgraphs or photographs presented at meetings. An author index is provided at the back of this volume for cross referencing

  16. Metaphor: Bridging embodiment to abstraction.

    Science.gov (United States)

    Jamrozik, Anja; McQuire, Marguerite; Cardillo, Eileen R; Chatterjee, Anjan

    2016-08-01

    Embodied cognition accounts posit that concepts are grounded in our sensory and motor systems. An important challenge for these accounts is explaining how abstract concepts, which do not directly call upon sensory or motor information, can be informed by experience. We propose that metaphor is one important vehicle guiding the development and use of abstract concepts. Metaphors allow us to draw on concrete, familiar domains to acquire and reason about abstract concepts. Additionally, repeated metaphoric use drawing on particular aspects of concrete experience can result in the development of new abstract representations. These abstractions, which are derived from embodied experience but lack much of the sensorimotor information associated with it, can then be flexibly applied to understand new situations.

  17. Technical abstracts: Mechanical engineering, 1990

    Energy Technology Data Exchange (ETDEWEB)

    Broesius, J.Y. (comp.)

    1991-03-01

    This document is a compilation of the published, unclassified abstracts produced by mechanical engineers at Lawrence Livermore National Laboratory (LLNL) during the calendar year 1990. Many abstracts summarize work completed and published in report form. These are UCRL-JC series documents, which include the full text of articles to be published in journals and of papers to be presented at meetings, and UCID reports, which are informal documents. Not all UCIDs contain abstracts: short summaries were generated when abstracts were not included. Technical Abstracts also provides descriptions of those documents assigned to the UCRL-MI (miscellaneous) category. These are generally viewgraphs or photographs presented at meetings. An author index is provided at the back of this volume for cross referencing.

  18. Abstract Interpretation and Attribute Gramars

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    The objective of this thesis is to explore the connections between abstract interpretation and attribute grammars as frameworks in program analysis. Abstract interpretation is a semantics-based program analysis method. A large class of data flow analysis problems can be expressed as non-standard ......The objective of this thesis is to explore the connections between abstract interpretation and attribute grammars as frameworks in program analysis. Abstract interpretation is a semantics-based program analysis method. A large class of data flow analysis problems can be expressed as non......-standard semantics where the ``meaning'' contains information about the runtime behaviour of programs. In an abstract interpretation the analysis is proved correct by relating it to the usual semantics for the language. Attribute grammars provide a method and notation to specify code generation and program analysis...

  19. Microwave imaging for plasma diagnostics and its applications

    International Nuclear Information System (INIS)

    Mase, A.; Kogi, Y.; Ito, N.

    2007-01-01

    Microwave to millimeter-wave diagnostic techniques such as interferometry, reflectometry, scattering, and radiometry have been powerful tools for diagnosing magnetically confined plasmas. Important plasma parameters were measured to clarify the physics issues such as stability, wave phenomena, and fluctuation-induced transport. Recent advances in microwave and millimeter-wave technology together with computer technology have enabled the development of advanced diagnostics for visualization of 2D and 3D structures of plasmas. Microwave/millimeter-wave imaging is expected to be one of the most promising diagnostic methods for this purpose. We report here on the representative microwave diagnostics and their industrial applications as well as application to magnetically-confined plasmas. (author)

  20. Microwave and conventional preparation of Zinc borate glass: Eu3+ ion as luminescent probe

    International Nuclear Information System (INIS)

    Mandal, Ashis K.; Balaji, S.; Sen, Ranjan

    2014-01-01

    Highlights: • IR transparent Zinc borate glass is prepared using microwave heating. • Glass transition temperature of microwave melted glass is found higher than that of glass prepared in conventional melting. • Low OH concentration in glass can be prepared in microwave heating. • We report higher reduction of Eu 3+ to Eu 2+ in microwave processing of Zinc borate glass. - Abstract: Transparent Zinc borate glass is melted using microwave energy as an alternative heating route to conventional resistive heating. A comparative study of the properties of the glasses prepared by both the methods is conducted by adopting X-ray diffraction (XRD), Differential scanning calorimetry (DSC), UV–VIS–NIR spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Refractive Indices (RI). Amorphous nature of samples is confirmed by X-ray diffraction study. Glass transition temperature (T g ) of microwave melted glass is found ∼7–9 °C higher than that of glass prepared in conventional melting. OH content is found less than 250 ppm in microwave melted glass whereas it is above 330 ppm in conventional melted glasses. Photoluminescence study of Eu 2 O 3 doped glass prepared in microwave heating indicates higher reduction of Eu 3+ → Eu 2+ than the glass melted in conventional route. Thus, microwave processing can be an alternative energy efficient, time saving, environmental friendly glass preparation method

  1. Ex situ thermo-catalytic upgrading of biomass pyrolysis vapors using a traveling wave microwave reactor

    International Nuclear Information System (INIS)

    Muley, P.D.; Henkel, C.E.; Aguilar, G.; Klasson, K.T.; Boldor, D.

    2016-01-01

    Highlights: • Ex-situ microwave reactor was used to heat catalyst bed for pyrolysis upgrading. • Results were compared with conventional catalytic reactor. • Microwave heating yielded higher aromatic compounds. • Catalyst deactivation due to coking was lower in microwave reactor. • 30% decrease in energy input for microwave reactor. - Abstract: Microwave heating offers a number of advantages over conventional heating methods, such as, rapid and volumetric heating, precise temperature control, energy efficiency and lower temperature gradient. In this article we demonstrate the use of 2450 MHz microwave traveling wave reactor to heat the catalyst bed for thermo-catalytic upgrading of pyrolysis vapors. HZSM-5 catalyst was tested at three different temperatures (290°, 330° and 370 °C) at a catalyst to biomass ratio of 2. Results were compared with conventional heating and induction heating method of catalyst bed. The yields of aromatic compounds and coke deposition were dependent on temperature and method of heating. Microwave heating yielded higher aromatic compounds and lower coke deposition. Microwave heating was also energy efficient compared to conventional reactors. The rate of catalyst deterioration was lower for catalyst heated in microwave system.

  2. Nuclear energy and environment: abstracts

    International Nuclear Information System (INIS)

    1999-01-01

    In this meeting on nuclear energy and environment, abstracts on the following subjects were presented: nuclear fuels; materials; radioisotopes and its applications; reactors and nuclear power plants; regulations, energy and environment; radioactive wastes; and analytical techniques

  3. The Cosmic Microwave Background

    Directory of Open Access Journals (Sweden)

    Jones Aled

    1998-01-01

    Full Text Available We present a brief review of current theory and observations of the cosmic microwave background (CMB. New predictions for cosmological defect theories and an overview of the inflationary theory are discussed. Recent results from various observations of the anisotropies of the microwave background are described and a summary of the proposed experiments is presented. A new analysis technique based on Bayesian statistics that can be used to reconstruct the underlying sky fluctuations is summarised. Current CMB data is used to set some preliminary constraints on the values of fundamental cosmological parameters $Omega$ and $H_circ$ using the maximum likelihood technique. In addition, secondary anisotropies due to the Sunyaev-Zel'dovich effect are described.

  4. Microwave superheaters for fusion

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, R.B.; Hoffman, M.A.; Logan, B.G.

    1987-10-16

    The microwave superheater uses the synchrotron radiation from a thermonuclear plasma to heat gas seeded with an alkali metal to temperatures far above the temperature of material walls. It can improve the efficiency of the Compact Fusion Advanced Rankine (CFAR) cycle described elsewhere in these proceedings. For a proof-of-principle experiment using helium, calculations show that a gas superheat ..delta..T of 2000/sup 0/K is possible when the wall temperature is maintained at 1000/sup 0/K. The concept can be scaled to reactor grade systems. Because of the need for synchrotron radiation, the microwave superheater is best suited for use with plasmas burning an advanced fuel such as D-/sup 3/He. 5 refs.

  5. Microwave multicomponent synthesis.

    Science.gov (United States)

    Hügel, Helmut M

    2009-12-01

    In the manner that very important research is often performed by multidisciplinary research teams, the applications of multicomponent reactions involving the combination of multiple starting materials with different functional groups leading to the higher efficiency and environmentally friendly construction of multifunctional/complex target molecules is growing in importance. This review will explore the advances and advantages in microwave multicomponent synthesis (MMS) that have been achieved over the last five years.

  6. Microwave Multicomponent Synthesis

    Directory of Open Access Journals (Sweden)

    Helmut M. Hügel

    2009-12-01

    Full Text Available In the manner that very important research is often performed by multidisciplinary research teams, the applications of multicomponent reactions involving the combination of multiple starting materials with different functional groups leading to the higher efficiency and environmentally friendly construction of multifunctional/complex target molecules is growing in importance. This review will explore the advances and advantages in microwave multicomponent synthesis (MMS that have been achieved over the last five years.

  7. Microwave Multicomponent Synthesis

    OpenAIRE

    Helmut M. Hügel

    2009-01-01

    In the manner that very important research is often performed by multidisciplinary research teams, the applications of multicomponent reactions involving the combination of multiple starting materials with different functional groups leading to the higher efficiency and environmentally friendly construction of multifunctional/complex target molecules is growing in importance. This review will explore the advances and advantages in microwave multicomponent synthesis (MMS) that have been achiev...

  8. Introduction to Microwave Linear [Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Whittum, David H

    1999-01-04

    The elements of microwave linear accelerators are introduced starting with the principles of acceleration and accelerating structures. Considerations for microwave structure modeling and design are developed from an elementary point of view. Basic elements of microwave electronics are described for application to the accelerator circuit and instrumentation. Concepts of beam physics are explored together with examples of common beamline instruments. Charged particle optics and lattice diagnostics are introduced. Considerations for fixed-target and colliding-beam experimentation are summarized.

  9. Microwave-Assisted Olefin Metathesis

    Science.gov (United States)

    Nicks, François; Borguet, Yannick; Sauvage, Xavier; Bicchielli, Dario; Delfosse, Sébastien; Delaude, Lionel; Demonceau, Albert

    Since the first reports on the use of microwave irradiation to accelerate organic chemical transformations, a plethora of papers have been published in this field. In most examples, microwave heating has been shown to dramatically reduce reaction times, increase product yields, and enhance product purity by reducing unwanted side reactions compared to conventional heating methods. The present contribution aims at illustrating the advantages of this technology in olefin metathesis and, when data are available, at comparing microwave-heated and conventionally heated experiments

  10. Microwave-assisted ADMET polymerization

    OpenAIRE

    Rojas Jiménez, Giovanni

    2015-01-01

    Microwave-assisted ADMET polymerization is reported on a series of α,ω-diene monomers, both polar and non-polar. Investigations indicate that of the multiple microwave modes possible, constant power is the most advantageous, providing polymers up to M‾w=31,000g/mol. Molecular weight values are nearly triple in comparison with conventional oil bath heating. Polymers are characterized by NMR, GPC, TGA, and DSC. Microwave irradiation provides a highly controllable and energy efficient ADMET poly...

  11. Influence of microwaves and electron beam on red blood cells

    International Nuclear Information System (INIS)

    Hategan, A.; Martin, D.; Popescu, A.; Butan, C.

    1999-01-01

    The effects of 6 MeV electron beam and of 2.45 GHz microwaves on the osmotic fragility of frozen cryoprotected human red blood cell membranes are presented. The changes in the properties of the red blood cell membranes were estimated by measuring the radiation induced haemoglobin release from the red blood cells (haemolysis) and the osmotic fragility of the membranes, determined by postirradiation induced osmotic stress. We obtained no haemolysis induced by accelerated electrons in the range 0 - 400 Gy, whereas the microwave irradiated red blood cells showed in the ranges 1 - 2 min and 400 - 500 W values of very small haemolysis, down to 50 % from the control. The osmotic stress experiments indicated a significant increase in the osmotic fragility for 200 - 400 Gy electron doses, whereas the 100 Gy irradiated sample showed a haemolysis down to 35 % from the control. Similarly, the microwave irradiated red blood cells showed values down to 60% from the control for (1 min, 850 W). Both radiations induced at definite parameters values of very small haemolysis, suggesting a stabilisation of the membranes and an increase in the osmotic resistance. Our preliminary results on simultaneous irradiation of the frozen red blood cells seem to indicate a significant contribution of the microwaves in haemolysis evolution, while the successive irradiation procedure did not allow so far a clear interpretation, further studies being necessary to elucidate the physico-chemical mechanisms induced. (authors)

  12. COST-EFFECTIVE BANDWIDTH PROVISIONING IN MICROWAVE WIRELESS NETWORKS UNDER UNRELIABLE CHANNEL CONDITIONS

    Directory of Open Access Journals (Sweden)

    Brigitte Jaumard

    Full Text Available ABSTRACT Cost-effective planning and dimensioning of backhaul microwave networks under unreliable channel conditions remains a relatively underexplored area in the literature. In particular, bandwidth assignment requires special attention as the transport capacity of microwave links is prone to variations due to, e.g., weather conditions. In this paper, we formulate an optimization model that determines the minimum cost bandwidth assignment of the links in the network for which traffic requirements can be fulfilled with high probability. This model also aims to increase network reliability by adjusting dynamically traffic routes in response to variations of link capacities induced by channel conditions. Experimental results show that 45% of the bandwidth cost can be saved compared to the case where a bandwidth over-provisioning policy is uniformly applied to all links in the network planning. Comparisons with previous work also show that our solution approach, based on column generation technique, is able to solve much larger instances in significantly shorter computing times (i.e., few minutes for medium-size networks, and up to 2 hours for very large networks, unsolved so far by previous models/algorithms, with a comparable level of reliability.

  13. The European Microwave Week 2008 and its Microwave Conferences

    NARCIS (Netherlands)

    Hoogeboom, P.; Van Vliet, F.

    2009-01-01

    Under the auspices of the European Microwave Association (EuMA) the 11th annual European Microwave Week was organized in the Amsterdam RAI Congress Centre, The Netherlands, 27-31 October 2008. This major event consisted this year of five conferences, an exhibition, and various side events. The 38th

  14. Mechanical Engineering Department technical abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1984-07-01

    The Mechanical Engineering Department publishes abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). General information about the current role and activities of each of the Department's seven divisions precedes the technical abstracts. Further information about a division's work may be obtained from the division leader, whose name is given at the end of each divisional summary. The Department's seven divisions are as follows: Nuclear Test Engineering Division, Nuclear Explosives Engineering Division, Weapons Engineering Division, Energy Systems Engineering Division, Engineering Sciences Division, Magnetic Fusion Engineering Division and Materials Fabrication Division.

  15. Mechanical Engineering Department technical abstracts

    International Nuclear Information System (INIS)

    1984-01-01

    The Mechanical Engineering Department publishes abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). General information about the current role and activities of each of the Department's seven divisions precedes the technical abstracts. Further information about a division's work may be obtained from the division leader, whose name is given at the end of each divisional summary. The Department's seven divisions are as follows: Nuclear Test Engineering Division, Nuclear Explosives Engineering Division, Weapons Engineering Division, Energy Systems Engineering Division, Engineering Sciences Division, Magnetic Fusion Engineering Division and Materials Fabrication Division

  16. Elements of abstract harmonic analysis

    CERN Document Server

    Bachman, George

    2013-01-01

    Elements of Abstract Harmonic Analysis provides an introduction to the fundamental concepts and basic theorems of abstract harmonic analysis. In order to give a reasonably complete and self-contained introduction to the subject, most of the proofs have been presented in great detail thereby making the development understandable to a very wide audience. Exercises have been supplied at the end of each chapter. Some of these are meant to extend the theory slightly while others should serve to test the reader's understanding of the material presented. The first chapter and part of the second give

  17. Abstracts from Rambam Research Day

    Directory of Open Access Journals (Sweden)

    Shraga Blazer

    2015-01-01

    Full Text Available [Extract] This Supplement of Rambam Maimonides Medical Journal presents the abstracts from the Eleventh Rambam Research Day. These abstracts represent the newest basic and clinical research coming out of Rambam Health Care Campus—research that is the oxygen for education and development of today’s generation of physicians. Hence, the research presented on Rambam Research Day is a foundation for future generations to understand patient needs and improve treatment modalities. Bringing research from the bench to the bedside and from the bedside to the community is at the heart of Maimonides’ scholarly and ethical legacy.

  18. Microwave absorption behavior in Cr2O3 nanopowders

    International Nuclear Information System (INIS)

    Montiel, H.; Alvarez, G.; Conde-Gallardo, A.; Zamorano, R.

    2015-01-01

    Highlights: • We have investigated the microwave power absorption in Cr 2 O 3 nanopowders. • EMR spectra show the contributions of the core and the surface of the nanoparticles. • MAMMAS detected an antiferro-paramagnetic transition due to core of the nanoparticles. • LFMA signal is associated with the ferromagnetic order on the surface of the nanoparticles. - Abstract: We have investigated the microwave power absorption at X-band (8.8–9.8 GHz) in Cr 2 O 3 nanopowders, for the 294–400 K temperature range. For all temperatures, two different kinds of microwave absorptions are observed: the electron magnetic resonance (EMR) at high magnetic field and the low-field microwave absorption (LFMA) around zero field. EMR spectrum can be separated in two contributions associated with two different resonant absorption modes, where this result is interpreted as the combination of two different magnetic phases; corresponding to the core (mode A) and the surface (mode B) of the Cr 2 O 3 nanoparticles. Also, we have detected the onset of the antiferro-paramagnetic transition in resonant mode A, which is characteristic of Cr 2 O 3 samples; being confirmed the magnetic transition by means of the magnetically modulated microwave absorption spectroscopy (MAMMAS). Additionally, the temperature behaviors of the resonant mode B and the LFMA signal are associated with a ferromagnetic state on the surface of the Cr 2 O 3 nanoparticles

  19. 2.45 GHz Microwave Radiation Impairs Learning and Spatial Memory via Oxidative/Nitrosative Stress Induced p53-Dependent/Independent Hippocampal Apoptosis: Molecular Basis and Underlying Mechanism.

    Science.gov (United States)

    Shahin, Saba; Banerjee, Somanshu; Singh, Surya Pal; Chaturvedi, Chandra Mohini

    2015-12-01

    A close association between microwave (MW) radiation exposure and neurobehavioral disorders has been postulated but the direct effects of MW radiation on central nervous system still remains contradictory. This study was performed to understand the effect of short (15 days) and long-term (30 and 60 days) low-level MW radiation exposure on hippocampus with special reference to spatial learning and memory and its underlying mechanism in Swiss strain male mice, Mus musculus. Twelve-weeks old mice were exposed to 2.45 GHz MW radiation (continuous-wave [CW] with overall average power density of 0.0248 mW/cm(2) and overall average whole body specific absorption rate value of 0.0146 W/Kg) for 2 h/day over a period of 15, 30, and 60 days). Spatial learning and memory was monitored by Morris Water Maze. We have checked the alterations in hippocampal oxidative/nitrosative stress, neuronal morphology, and expression of pro-apoptotic proteins (p53 and Bax), inactive executioner Caspase- (pro-Caspase-3), and uncleaved Poly (ADP-ribose) polymerase-1 in the hippocampal subfield neuronal and nonneuronal cells (DG, CA1, CA2, and CA3). We observed that, short-term as well as long-term 2.45 GHz MW radiation exposure increases the oxidative/nitrosative stress leading to enhanced apoptosis in hippocampal subfield neuronal and nonneuronal cells. Present findings also suggest that learning and spatial memory deficit which increases with the increased duration of MW exposure (15 stress induced p53-dependent/independent activation of hippocampal neuronal and nonneuronal apoptosis associated with spatial memory loss. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Interaction of microwave radiation with the high mobility two-dimensional electron system in GaAs/AlGaAs heterostructures

    International Nuclear Information System (INIS)

    Ramanayaka, A.N.; Ye, Tianyu; Liu, H.-C.; Wegscheider, W.; Mani, R.G.

    2014-01-01

    The influence of microwave excitation on the magnetotransport properties of the high mobility two-dimensional electron system (2DES) in the GaAs/AlGaAs heterostructure system is investigated by exploring (a) the dependence of the amplitude of the microwave-induced magnetoresistance-oscillations on the polarization direction of the linearly polarized microwaves and (b) the microwave reflection from the 2DES. The polarization study indicates that the amplitude of the magnetoresistance oscillations is remarkably responsive to the relative orientation between the linearly polarized microwaves and the current-axis in the specimen. At low microwave power, P, experiments indicate a strong sinusoidal variation in the diagonal resistance R xx vs. θ at the oscillatory extrema of the microwave-induced magnetoresistance oscillations. The reflection study indicates strong correlations between the microwave induced magnetoresistance oscillations and oscillatory features in the microwave reflection in a concurrent measurement of the magnetoresistance and the microwave magnetoreflection from the 2DES. The correlations are followed as a function of the microwave frequency and the microwave power, and the results are reported

  1. Rock Crushing Using Microwave Pre-Treatment

    KAUST Repository

    Kim, Seunghee

    2016-08-11

    Crushing and grinding are primary contributors to a high energy demand in the mining industry, yet, both are surprisingly inefficient processes, often with efficiencies as low as 1%. We analyze size reductions during crushing and grinding operations and explore the potential of multiplying internal weaknesses in rock materials by non-mechanical means. In particular, when rock blocks (wet or even dry if polycrystalline) are exposed to microwaves, internal cracks can develop along grain boundaries via differential thermal expansion between grains and volumetric thermal expansion of water in pores. Brazilian tests conducted on granite and cement mortar specimens show that the tensile strength decreases proportional to the duration of microwave treatment. Thermal changes, excessive fluid pressure buildup and induced stresses are analyzed in the context of hydro-Thermo-mechanically coupled processes. Results confirm that both differential thermal expansion of mineral grains and volumetric thermal expansion of water can generate cracks upon microwave exposure. Optimal conditions are suggested to lower the combined consumption of electric and mechanical energy.

  2. Adoption of microwave ovens among a sample of older adults in Blacksburg, Virginia

    OpenAIRE

    Nagarajan, Anandi III

    1998-01-01

    ABSTRACT The purpose of this study was to identify the extent of adoption of microwave ovens by older adults in Blacksburg, Virginia. Level of adoption was defined and determined as a function of 1) frequency of use of the microwave oven in comparison to the range, and 2) complexity of food preparation. Mere ownership was not considered as an indicator of adoption. Focusing on the final stage of Rogers theory of adoption (1962), three levels of adoption were determined: High, mediu...

  3. Microwave and Pulsed Power

    Energy Technology Data Exchange (ETDEWEB)

    Freytag, E.K.

    1993-03-01

    The goals of the Microwave and Pulsed Power thrust area are to identify realizable research and development efforts and to conduct high-quality research in those pulse power and microwave technologies that support existing and emerging programmatic requirements at Lawrence Livermore National Laboratory (LLNL). Our main objective is to work on nationally important problems while enhancing our basic understanding of enabling technologies such as component design and testing, compact systems packaging, exploratory physics experiments, and advanced systems integration and performance. During FY-92, we concentrated our research efforts on the six project areas described in this report. (1) We are investigating the superior electronic and thermal properties of diamond that may make it an ideal material for a high-power, solid-state switch. (2) We are studying the feasibility of using advanced Ground Penetrating Imaging Radar technology for reliable non-destructive evaluation of bridges and other high-value concrete structures. These studies include conceptual designs, modeling, experimental verifications, and image reconstruction of simulated radar data. (3) We are exploring the efficiency of pulsed plasma processing techniques used for the removal of NO{sub x} from various effluent sources. (4) We have finished the investigation of the properties of a magnetically delayed low-pressure gas switch, which was designed here at LLNL. (5) We are applying statistical electromagnetic theory techniques to help assess microwave effects on electronic subsystems, by using a mode stirred chamber as our measurement tool. (6) We are investigating the generation of perfluoroisobutylene (PFIB) in proposed CFC replacement fluids when they are subjected to high electrical stresses and breakdown environments.

  4. Abstract Interpretation of Mobile Ambients

    DEFF Research Database (Denmark)

    Hansen, René Rydhof; Jensen, J. G.; Nielson, Flemming

    1999-01-01

    We demonstrate that abstract interpretation is useful for analysing calculi of computation such as the ambient calculus (which is based on the p-calculus); more importantly, we show that the entire development can be expressed in a constraint-based formalism that is becoming exceedingly popular...

  5. Abstract Résumé

    African Journals Online (AJOL)

    Abstract. To describe the infant feeding practices in the general population in Uganda, and to assess the impact of maternal HIV status on these ... to-child transmission of HIV should re-enforce counselling activities to address the issue of early weaning by HIV-infected women, ..... A study in Zimbabwe yielded similar results,.

  6. Biocards and Level of Abstraction

    DEFF Research Database (Denmark)

    Lenau, Torben Anker; Keshwani, Sonal; Chakrabarti, Amaresh

    2015-01-01

    Biocards are formal descriptions of biological phenomena and their underlying functional principles. They are used in bioinspired design to document search results and to communicate the findings for use in the further design process. The present study explored the effect of abstraction level use...

  7. IRAP 2006, Book of Abstracts

    International Nuclear Information System (INIS)

    2006-01-01

    This publications related with Hacettepe University, Turkish Atomic Energy Authority, The Scientific and Technological Research Council of Turkey, International Atomic Energy Agency, CEA-Saclay, CEA-Saclay Drecam, ANKAmall Shopping Center and Ion Beam Applications Industrial that was held in Antalya, Turkey, 23-28 September 2006. A separate abstract was prepared for each paper

  8. Abstract Résumé

    African Journals Online (AJOL)

    1 juil. 2013 ... Abstract. In Senegal, where HIV prevalence is less than 1% and stigma remains important, 40% of marriages are polygamic. The purpose of this article is to describe and analyze the motivations, benefits and constraints related to HIV disclosure, and to explore specific situations related to polygamy.

  9. Metaphoric Images from Abstract Concepts.

    Science.gov (United States)

    Vizmuller-Zocco, Jana

    1992-01-01

    Discusses children's use of metaphors to create meaning, using as an example the pragmatic and "scientific" ways in which preschool children explain thunder and lightning to themselves. Argues that children are being shortchanged by modern scientific notions of abstractness and that they should be encouraged to create their own explanations of…

  10. The Complexity of Abstract Machines

    Directory of Open Access Journals (Sweden)

    Beniamino Accattoli

    2017-01-01

    Full Text Available The lambda-calculus is a peculiar computational model whose definition does not come with a notion of machine. Unsurprisingly, implementations of the lambda-calculus have been studied for decades. Abstract machines are implementations schema for fixed evaluation strategies that are a compromise between theory and practice: they are concrete enough to provide a notion of machine and abstract enough to avoid the many intricacies of actual implementations. There is an extensive literature about abstract machines for the lambda-calculus, and yet—quite mysteriously—the efficiency of these machines with respect to the strategy that they implement has almost never been studied. This paper provides an unusual introduction to abstract machines, based on the complexity of their overhead with respect to the length of the implemented strategies. It is conceived to be a tutorial, focusing on the case study of implementing the weak head (call-by-name strategy, and yet it is an original re-elaboration of known results. Moreover, some of the observation contained here never appeared in print before.

  11. Rolloff Roof Observatory Construction (Abstract)

    Science.gov (United States)

    Ulowetz, J. H.

    2015-12-01

    (Abstract only) Lessons learned about building an observatory by someone with limited construction experience, and the advantages of having one for imaging and variable star studies. Sample results shown of composite light curves for cataclysmic variables UX UMa and V1101 Aql with data from my observatory combined with data from others around the world.

  12. Abstract Expressionism. Clip and Save.

    Science.gov (United States)

    Hubbard, Guy

    2002-01-01

    Provides information on the art movement, Abstract Expressionism, and includes learning activities. Focuses on the artist Jackson Pollock, offering a reproduction of his artwork, "Convergence: Number 10." Includes background information on the life and career of Pollock and a description of the included artwork. (CMK)

  13. Original Abstracts - Supplementary | Conference Contributors ...

    African Journals Online (AJOL)

    All abstracts from the The Annual Medical Research Day (AMRD) held at the University of Zimbabwe. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about ...

  14. Advances on integrated microwave photonics

    DEFF Research Database (Denmark)

    Dong, Jianji; Liao, Shasha; Yan, Siqi

    2017-01-01

    Integrated microwave photonics has attracted a lot of attentions and makes significant improvement in last 10 years. We have proposed and demonstrated several schemes about microwave photonics including waveform generation, signal processing and energy-efficient micro-heaters. Our schemes are all...

  15. Microstrip microwave band gap structures

    Indian Academy of Sciences (India)

    Microwave band gap structures exhibit certain stop band characteristics based on the periodicity, impedance contrast and effective refractive index contrast. These structures though formed in one-, two- and three-dimensional periodicity, are huge in size. In this paper, microstrip-based microwave band gap structures are ...

  16. Microwave Sterilization in School Microbiology.

    Science.gov (United States)

    Wynn, Brian; Dixon, Angela

    1988-01-01

    Described are two investigations carried out in a high school biology department using a domestic microwave oven to compare the relative attributes of the autoclave and microwave oven in school use. Discussed are equipment, methods, and results of each investigation. (Author/CW)

  17. Microwave Radiometry in Remote Sensing

    DEFF Research Database (Denmark)

    Gudmandsen, Preben

    1982-01-01

    Microwave radiometry has shown its capabilities of observing and monitoring large-scale geophysical observables from space. Examples are sea surface temperature and surface wind over the ocean, sea ice extent, concentration and category and snow cover extent and water content. At low microwave fr...

  18. Blends of ground tire rubber devulcanized by microwaves/HDPE - Part A: influence of devulcanization process

    Directory of Open Access Journals (Sweden)

    Fabiula Danielli Bastos de Sousa

    2015-06-01

    Full Text Available AbstractThe main objective of this work is the study of the influence of microwaves devulcanization of the elastomeric phase on dynamically revulcanized blends based on Ground Tire Rubber (GTR/High Density Polyethylene (HDPE. The devulcanization of the GTR was performed in a system comprised of a conventional microwave oven adapted with a motorized stirring at a constant microwaves power and at various exposure times. The influence of the devulcanization process on the final properties of the blends was evaluated in terms of mechanical, viscoelastic, thermal and rheological properties. The morphology was also studied.

  19. Resonant freak microwaves

    International Nuclear Information System (INIS)

    Aguiar, F.M. de

    2011-01-01

    The Helmholtz equation describing transverse magnetic modes in a closed flat microwave resonator with 60 randomly distributed discs is numerically solved. At lower frequencies, the calculated wave intensity spatially distributed obeys the universal Porter-Thomas form if localized modes are excluded. A superposition of resonant modes is shown to lead to rare events of extreme intensities (freak waves) at localized 'hot spots'. The temporally distributed intensity of such a superposition at the center of a hot spot also follows the Porter-Thomas form. Branched modes are found at higher frequencies. The results bear resemblance to recent experiments reported in an open cavity.

  20. DSN Microwave Antenna Holography

    Science.gov (United States)

    Rochblatt, D. J.; Seidel, B. L.

    1984-01-01

    The DSN microwave antenna holography project will obtain three-dimensional pictures of the large DSN antenna surfaces. These pictures must be of suffi icient resolution to allow adjustment of the reflector panels to an rms surface of 0.5 mm (0.25 mm, goal). The major parameters and equations needed to define a holographic measurement system are outlined and then the proof of concept demonstration measurement that was made at DSS-43 (Australia) that resulted in contour maps with spatial resolution of 7 m in the aperture plane and resolution orthogonal to the aperture plane of 0.7 mm was discussed.

  1. Microwave-Assisted Functionalization of Carbon Nanotubes and Reactive Synthesis of Nanocomposites, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Offerers will build on their recent innovation of a microwave-induced route to the rapid functionalization, solubilization and reactive synthesis of carbon...

  2. Passive Microwave Components and Antennas

    DEFF Research Database (Denmark)

    State-of-the-art microwave systems always require higher performance and lower cost microwave components. Constantly growing demands and performance requirements of industrial and scientific applications often make employing traditionally designed components impractical. For that reason, the design...... and development process remains a great challenge today. This problem motivated intensive research efforts in microwave design and technology, which is responsible for a great number of recently appeared alternative approaches to analysis and design of microwave components and antennas. This book highlights...... techniques. Modelling and computations in electromagnetics is a quite fast-growing research area. The recent interest in this field is caused by the increased demand for designing complex microwave components, modeling electromagnetic materials, and rapid increase in computational power for calculation...

  3. Peak effect in surface resistance at microwave frequencies in Dy ...

    Indian Academy of Sciences (India)

    In the measurements at both frequencies the induced microwave current was always less than the critical current of the films. The reason for observation of this peak effect in these films has been explained in our earlier publication [5]. Comparing figures 1 and 2, it is observed that the peaks in sample S1 are broader and.

  4. Microwave dependence of subharmonic gap structure in superconducting junctions

    DEFF Research Database (Denmark)

    Sørensen, O. Hoffman; Kofoed, Bent; Pedersen, Niels Falsig

    1974-01-01

    are integers: m=1,2,3,… and n=0,1,2,…. The power dependence of the satellite structure and the microwave-assisted tunneling structure is consistent for all junctions tested with the expression Jn2(m e Vrf / h ν), where Jn(x) is the ordinary Bessel function of order n, Vrf is the amplitude of the induced...

  5. The abstract representations in speech processing.

    Science.gov (United States)

    Cutler, Anne

    2008-11-01

    Speech processing by human listeners derives meaning from acoustic input via intermediate steps involving abstract representations of what has been heard. Recent results from several lines of research are here brought together to shed light on the nature and role of these representations. In spoken-word recognition, representations of phonological form and of conceptual content are dissociable. This follows from the independence of patterns of priming for a word's form and its meaning. The nature of the phonological-form representations is determined not only by acoustic-phonetic input but also by other sources of information, including metalinguistic knowledge. This follows from evidence that listeners can store two forms as different without showing any evidence of being able to detect the difference in question when they listen to speech. The lexical representations are in turn separate from prelexical representations, which are also abstract in nature. This follows from evidence that perceptual learning about speaker-specific phoneme realization, induced on the basis of a few words, generalizes across the whole lexicon to inform the recognition of all words containing the same phoneme. The efficiency of human speech processing has its basis in the rapid execution of operations over abstract representations.

  6. Abstract Cauchy problems three approaches

    CERN Document Server

    Melnikova, Irina V

    2001-01-01

    Although the theory of well-posed Cauchy problems is reasonably understood, ill-posed problems-involved in a numerous mathematical models in physics, engineering, and finance- can be approached in a variety of ways. Historically, there have been three major strategies for dealing with such problems: semigroup, abstract distribution, and regularization methods. Semigroup and distribution methods restore well-posedness, in a modern weak sense. Regularization methods provide approximate solutions to ill-posed problems. Although these approaches were extensively developed over the last decades by many researchers, nowhere could one find a comprehensive treatment of all three approaches.Abstract Cauchy Problems: Three Approaches provides an innovative, self-contained account of these methods and, furthermore, demonstrates and studies some of the profound connections between them. The authors discuss the application of different methods not only to the Cauchy problem that is not well-posed in the classical sense, b...

  7. Learning abstract algebra with ISETL

    CERN Document Server

    Dubinsky, Ed

    1994-01-01

    Most students in abstract algebra classes have great difficulty making sense of what the instructor is saying. Moreover, this seems to remain true almost independently of the quality of the lecture. This book is based on the constructivist belief that, before students can make sense of any presentation of abstract mathematics, they need to be engaged in mental activities which will establish an experiential base for any future verbal explanation. No less, they need to have the opportunity to reflect on their activities. This approach is based on extensive theoretical and empirical studies as well as on the substantial experience of the authors in teaching astract algebra. The main source of activities in this course is computer constructions, specifically, small programs written in the mathlike programming language ISETL; the main tool for reflections is work in teams of 2-4 students, where the activities are discussed and debated. Because of the similarity of ISETL expressions to standard written mathematics...

  8. IEEE conference record -- Abstracts: 1996 IEEE international conference on plasma science

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    This meeting covered the following topics: space plasmas; non-equilibrium plasma processing; computer simulation of vacuum power tubes; vacuum microelectronics; microwave systems; basic phenomena in partially ionized gases -- gaseous electronics, electrical discharges; ball lightning/spherical plasma configuration; plasma diagnostics; plasmas for lighting; dense plasma focus; intense ion and electron beams; plasma, ion, and electron sources; flat panel displays; fast z-pinches and x-ray lasers; environmental/energy issues in plasma science; thermal plasma processing; computational plasma physics; magnetic confinement fusion; microwave-plasma interactions; space plasma engineering; EM and ETH launchers; fast wave devices; intense beam microwaves; slow wave devices; space plasma measurements; basic phenomena in fully ionized plasma -- waves, instabilities, plasma theory, etc; plasma closing switches; fast opening switches; and laser-produced plasma. Separate abstracts were prepared for most papers in this conference

  9. IEEE conference record -- Abstracts: 1996 IEEE international conference on plasma science

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This meeting covered the following topics: space plasmas; non-equilibrium plasma processing; computer simulation of vacuum power tubes; vacuum microelectronics; microwave systems; basic phenomena in partially ionized gases -- gaseous electronics, electrical discharges; ball lightning/spherical plasma configuration; plasma diagnostics; plasmas for lighting; dense plasma focus; intense ion and electron beams; plasma, ion, and electron sources; flat panel displays; fast z-pinches and x-ray lasers; environmental/energy issues in plasma science; thermal plasma processing; computational plasma physics; magnetic confinement fusion; microwave-plasma interactions; space plasma engineering; EM and ETH launchers; fast wave devices; intense beam microwaves; slow wave devices; space plasma measurements; basic phenomena in fully ionized plasma -- waves, instabilities, plasma theory, etc; plasma closing switches; fast opening switches; and laser-produced plasma. Separate abstracts were prepared for most papers in this conference.

  10. Abstract Interpretation Using Attribute Grammar

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    1990-01-01

    This paper deals with the correctness proofs of attribute grammars using methods from abstract interpretation. The technique will be described by defining a live-variable analysis for a small flow-chart language and proving it correct with respect to a continuation style semantics. The proof...... technique is based on fixpoint induction and introduces an extended class of attribute grammars as to express a standard semantics....

  11. Norddesign 2012 - Book of Abstract

    DEFF Research Database (Denmark)

    has been organized in line with the original ideas. The topics mentioned in the call for abstracts were: Product Development: Integrated, Multidisciplinary, Product life oriented and Distributed. Multi-product Development. Innovation and Business Models. Engineering Design and Industrial Design....... Conceptualisation and Innovative thinking. Research approaches and topics: Human Behaviour and Cognition. Cooperation and Multidisciplinary Design. Staging and Management of Design. Communication in Design. Design education and teaching: Programmes and Syllabuses. New Courses. Integrated and Multi-disciplinary. We...

  12. One-step template-free synthesis of monoporous polymer microspheres with uniform sizes via microwave-mediated dispersion polymerization.

    Science.gov (United States)

    Zhu, Ming-Qiang; Chen, Gan-Chao; Li, Yun-Mei; Fan, Jun-Bing; Zhu, Ming-Feng; Tang, Zhiyong

    2011-11-01

    One-step facile synthesis of monoporous polymer microspheres via microwave-controlled dispersion polymerization is introduced. This template-free method employing the dispersion polymerization of styrene under microwave irradiation induces directly the formation of uniform monoporous polymer microspheres, with controllable morphologies and sizes, which can be tuned by simply adjusting parameters for the synthesis. A comparison to conventional heating indicates that microwave irradiation plays a vital role in the formation of this novel morphology.

  13. 21 CFR 1030.10 - Microwave ovens.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Microwave ovens. 1030.10 Section 1030.10 Food and... HEALTH PERFORMANCE STANDARDS FOR MICROWAVE AND RADIO FREQUENCY EMITTING PRODUCTS § 1030.10 Microwave ovens. (a) Applicability. The provisions of this standard are applicable to microwave ovens manufactured...

  14. Microwave mixer technology and applications

    CERN Document Server

    Henderson, Bert

    2013-01-01

    Although microwave mixers play a critical role in wireless communication and other microwave applications employing frequency conversion circuits, engineers find that most books on this subject emphasize theoretical aspects, rather than practical applications. That's about to change with the forthcoming release of Microwave Mixer Technology and Applications. Based on a review of over one thousand patents on mixers and frequency conversion, authors Bert Henderson and Edmar Camargo have written a comprehensive book for mixer designers who want solid ideas for solving their own design challenges.

  15. The microwave Tokamak experiment (MTX)

    International Nuclear Information System (INIS)

    Thomassen, K.I.; Cohen, B.I.; Hooper, E.B.; Lang, D.D.; Nevins, W.M.

    1987-01-01

    A new experimental facility is being assembled at the Lawrence Livermore National Laboratory (LLNL) for studying microwave propagation and absorption in high density plasmas. A unique feature of the facility is the free electron laser (FEL) used to generate high peak power microwaves at 250 GHz, at a repetition rate so as to produce up to 2 MW of average power for up to 30 s. Called the Microwave Tokamak Experiment (MTX), the facility will be used for studies of plasma heating, current drive, and confinement

  16. Microwave and thermal curing of an epoxy resin for microelectronic applications

    International Nuclear Information System (INIS)

    Johnston, K.; Pavuluri, S.K.; Leonard, M.T.; Desmulliez, M.P.Y.; Arrighi, V.

    2015-01-01

    Graphical abstract: - Highlights: • Thermal and microwave curing of a commercial epoxy resin EO1080 are compared. • Microwave curing increases cure rate and does not adversely affect properties. • The curing of EO1080 is generally autocatalytic but deviates at high conversion. • Microwave radiation has a more complex effect on curing kinetics. - Abstract: Microwave curing of thermosetting polymers has a number of advantages to natural or thermal oven curing and is considered a cost-effective alternative. Here we present a detailed study of a commercially available epoxy resin, EO1080. Samples that are thermally cured are compared to curing using a recently developed modular microwave processing system. For commercial purposes it is crucial to demonstrate that microwave curing does not adversely affect the thermal and chemical properties of the material. Therefore, the kinetics of cure and various post cure properties of the resin are investigated. Attenuated Total Reflectance Fourier-Transform Infrared (ATR-FTIR) analysis shows no significant difference between the conventionally and microwave cured samples. Differential scanning calorimetry (DSC) is used to monitor the kinetics of the curing reaction, as well as determine the thermal and ageing properties of the material. As expected, the rate of curing is higher when using microwave energy and we attempt to quantify differences compared to conventional thermal curing. No change in glass transition temperature (T g ) is observed. For the first time, enthalpy relaxation measurements performed on conventional and microwave cured samples are reported and these indicate similar ageing properties at any given temperature under T g

  17. Cadmium extraction from phosphate ore. Effect of microwave

    Directory of Open Access Journals (Sweden)

    Zahia Benredjem

    2016-09-01

    Full Text Available This study discusses the operating variables for removal of cadmium from phosphate ore using Na2EDTA. These variables include the reaction time, Na2EDTA concentration, liquid/phosphate ore ratio, number of extractions and microwave extraction. Na2EDTA induced a two-step extraction process including a rapid extraction within the first hour, and a subsequent gradual release that occurred over the following hours. The cadmium extraction efficiency increased progressively with the increasing of Na2EDTA concentration. The extraction efficiency of cadmium increased with increasing liquid/phosphate ratio in the 5–200 range. Consecutive extractions using low concentrations were more effective than a single soil extraction with concentrated Na2EDTA. Microwave was beneficial to improve the removal in soil washing, and using microwave could partly substitute for agitation.

  18. Microwave antenna holography

    Science.gov (United States)

    Rochblatt, David J.; Seidel, Boris L.

    1992-01-01

    This microwave holography technique utilizes the Fourier transform relation between the complex far field radiation pattern of an antenna and the complex aperture field distribution. Resulting aperture phase and amplitude distribution data can be used to precisely characterize various crucial performance parameters, including panel alignment, panel shaping, subreflector position, antenna aperture illumination, directivity at various frequencies, and gravity deformation effects. The methodology of data processing presented here was successfully applied to the Deep Space Network (DSN) 34-m beam waveguide antennas. The antenna performance was improved at all operating frequencies by reducing the main reflector mechanical surface rms error to 0.43 mm. At Ka-band (32 GHz), the estimated improvement is 4.1 dB, resulting in an aperture efficiency of 52 percent. The performance improvement was verified by efficiency measurements and additional holographic measurements.

  19. National Physics Conference. Paper Abstracts

    International Nuclear Information System (INIS)

    Marinela Dumitriu, Editorial Coordination.

    1995-01-01

    This book contains the abstracts of the proceedings of the annual Romanian Physics Conference organized by Romanian Physics Society. The conference was held on November 30 to December 2, 1995 in the city of Baia Mare. It was organized in the following nine sections: 1 - Astrophysics, Particle Physics, Nuclear Physics, Molecular and Atomic Physics; 2 - Plasma Physics; 3 - Biophysics; 4 - Technical Physics; 5 - Theoretical Physics; 6 -The Physics of Energy; 7 - The Physics of Environment 8 - Solid State Physics; 9 - Optical and Quantum Electronics. The full texts can be obtained on request from the Romanian Physical Society or directly from authors

  20. WIPR-2010 Book of abstracts

    International Nuclear Information System (INIS)

    2015-01-01

    The main objective of the workshop was to review advanced and preclinical studies on innovative positron emitting radionuclides to assess their usefulness and potentials. Presentations were organized around 4 issues: 1) preclinical and clinical point of view, 2) production of innovative PET radionuclides, 3) from complexation chemistry to PET imaging and 4) from research to clinic. Emphasis has been put on 64 Cu, 68 Ga, 89 Zr, 44 Sc but specific aspects such as production or purification have been considered for 66 Ga, 67 Ga, 52 Fe, 86 Y, and 68 Ge radionuclides. This document gathers the abstracts of most contributions

  1. In-Package Chemistry Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    P.S. Domski

    2003-07-21

    The work associated with the development of this model report was performed in accordance with the requirements established in ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of SR and LA'' (BSC 2002a). The in-package chemistry model and in-package chemistry model abstraction are developed to predict the bulk chemistry inside of a failed waste package and to provide simplified expressions of that chemistry. The purpose of this work is to provide the abstraction model to the Performance Assessment Project and the Waste Form Department for development of geochemical models of the waste package interior. The scope of this model report is to describe the development and validation of the in-package chemistry model and in-package chemistry model abstraction. The in-package chemistry model will consider chemical interactions of water with the waste package materials and the waste form for commercial spent nuclear fuel (CSNF) and codisposed high-level waste glass (HLWG) and N Reactor spent fuel (CDNR). The in-package chemistry model includes two sub-models, the first a water vapor condensation (WVC) model, where water enters a waste package as vapor and forms a film on the waste package components with subsequent film reactions with the waste package materials and waste form--this is a no-flow model, the reacted fluids do not exit the waste package via advection. The second sub-model of the in-package chemistry model is the seepage dripping model (SDM), where water, water that may have seeped into the repository from the surrounding rock, enters a failed waste package and reacts with the waste package components and waste form, and then exits the waste package with no accumulation of reacted water in the waste package. Both of the submodels of the in-package chemistry model are film models in contrast to past in-package chemistry models where all of the waste package pore space was filled with water. The

  2. Operating System Abstraction Layer (OSAL)

    Science.gov (United States)

    Yanchik, Nicholas J.

    2007-01-01

    This viewgraph presentation reviews the concept of the Operating System Abstraction Layer (OSAL) and its benefits. The OSAL is A small layer of software that allows programs to run on many different operating systems and hardware platforms It runs independent of the underlying OS & hardware and it is self-contained. The benefits of OSAL are that it removes dependencies from any one operating system, promotes portable, reusable flight software. It allows for Core Flight software (FSW) to be built for multiple processors and operating systems. The presentation discusses the functionality, the various OSAL releases, and describes the specifications.

  3. Abstract decomposition theorem and applications

    CERN Document Server

    Grossberg, R; Grossberg, Rami; Lessmann, Olivier

    2005-01-01

    Let K be an Abstract Elementary Class. Under the asusmptions that K has a nicely behaved forking-like notion, regular types and existence of some prime models we establish a decomposition theorem for such classes. The decomposition implies a main gap result for the class K. The setting is general enough to cover \\aleph_0-stable first-order theories (proved by Shelah in 1982), Excellent Classes of atomic models of a first order tehory (proved Grossberg and Hart 1987) and the class of submodels of a large sequentially homogenuus \\aleph_0-stable model (which is new).

  4. Indico CONFERENCE: Define the Call for Abstracts

    CERN Multimedia

    CERN. Geneva; Ferreira, Pedro

    2017-01-01

    In this tutorial, you will learn how to define and open a call for abstracts. When defining a call for abstracts, you will be able to define settings related to the type of questions asked during a review of an abstract, select the users who will review the abstracts, decide when to open the call for abstracts, and more.

  5. Study of microwave instability

    International Nuclear Information System (INIS)

    Heifets, S.; Chao, A.

    1996-12-01

    The microwave instability is usually described by linearizing Vlasov equation in the angle-action variables I, φ and assuming that the interaction of azimuthal harmonics ρ n (I) of the distribution function ρ is weak. The argument implied here is that the Hamiltonian flow smears out particles over invariant tori characterized by the action variables, and the remaining azimuthal dependence of the distribution function is small. Indeed, such an approach successfully describes bunch spectrum and the threshold of the microwave instability. However, recently there have been interesting observations of bunch centroid and bunch shape oscillations above instability threshold at LEP and the damping ring at SLAC. There are also indicates that the oscillations sometimes occur in localized region in the longitudinal coordinate instead of affecting the entire longitudinal distribution as one expects by an action-angle analysis. In this paper the authors describe an alternative approach to the problem of bunch stability using decomposition of the Fokker-Plank equation in the system of nonlinear equations for the moments of the distribution function. In particular, this approach allows them to avoid the conventional action-angle decomposition. The physical quantities they are interested in, the moments, are expressed in the Cartesian z - δ phase space. To close the infinite hierarchy of moments equations, the authors assume that higher order correlations are small. Although both the action-angle and the Cartesian languages must be equivalent before truncation, they may have different speed of convergence depending on the problem being studied. It is hoped that Cartesian expansion approach would converge faster for the cases corresponding to those observed recently above threshold. The recent experimental observations made them interested in it again. This note is a progress report of their work

  6. Microwave Thermal Propulsion

    Science.gov (United States)

    Parkin, Kevin L. G.; Lambot, Thomas

    2017-01-01

    We have conducted research in microwave thermal propulsion as part of the space exploration access technologies (SEAT) research program, a cooperative agreement (NNX09AF52A) between NASA and Carnegie Mellon University. The SEAT program commenced on the 19th of February 2009 and concluded on the 30th of September 2015. The DARPA/NASA Millimeter-wave Thermal Launch System (MTLS) project subsumed the SEAT program from May 2012 to March 2014 and one of us (Parkin) served as its principal investigator and chief engineer. The MTLS project had no final report of its own, so we have included the MTLS work in this report and incorporate its conclusions here. In the six years from 2009 until 2015 there has been significant progress in millimeter-wave thermal rocketry (a subset of microwave thermal rocketry), most of which has been made under the auspices of the SEAT and MTLS programs. This final report is intended for multiple audiences. For researchers, we present techniques that we have developed to simplify and quantify the performance of thermal rockets and their constituent technologies. For program managers, we detail the facilities that we have built and the outcomes of experiments that were conducted using them. We also include incomplete and unfruitful lines of research. For decision-makers, we introduce the millimeter-wave thermal rocket in historical context. Considering the economic significance of space launch, we present a brief but significant cost-benefit analysis, for the first time showing that there is a compelling economic case for replacing conventional rockets with millimeter-wave thermal rockets.

  7. Deviation from normal Boltzmann distribution of high-lying energy levels of iron atom excited by Okamoto-cavity microwave-induced plasmas using pure nitrogen and nitrogen–oxygen gases

    International Nuclear Information System (INIS)

    Wagatsuma, Kazuaki

    2015-01-01

    This paper describes several interesting excitation phenomena occurring in a microwave-induced plasma (MIP) excited with Okamoto-cavity, especially when a small amount of oxygen was mixed with nitrogen matrix in the composition of the plasma gas. An ion-to-atom ratio of iron, which was estimated from the intensity ratio of ion to atomic lines having almost the same excitation energy, was reduced by adding oxygen gas to the nitrogen MIP, eventually contributing to an enhancement in the emission intensities of the atomic lines. Furthermore, Boltzmann plots for iron atomic lines were observed in a wide range of the excitation energy from 3.4 to 6.9 eV, indicating that plots of the atomic lines having lower excitation energies (3.4 to 4.8 eV) were well fitted on a straight line while those having more than 5.5 eV deviated upwards from the linear relationship. This overpopulation would result from any other excitation process in addition to the thermal excitation that principally determines the Boltzmann distribution. A Penning-type collision with excited species of nitrogen molecules probably explains this additional excitation mechanism, in which the resulting iron ions recombine with captured electrons, followed by cascade de-excitations between closely-spaced excited levels just below the ionization limit. As a result, these high-lying levels might be more populated than the low-lying levels of iron atom. The ionization of iron would be caused less actively in the nitrogen–oxygen plasma than in a pure nitrogen plasma, because excited species of nitrogen molecule, which can provide the ionization energy in a collision with iron atom, are consumed through collisions with oxygen molecules to cause their dissociation. It was also observed that the overpopulation occurred to a lesser extent when oxygen gas was added to the nitrogen plasma. The reason for this was also attributed to decreased number density of the excited nitrogen species due to collisions with oxygen

  8. Fiber Reinforced Polyester Resins Polymerized by Microwave Source

    Science.gov (United States)

    Visco, A. M.; Calabrese, L.; Cianciafara, P.; Bonaccorsi, L.; Proverbio, E.

    2007-12-01

    Polyester resin based composite materials are widely used in the manufacture of fiberglass boats. Production time of fiberglass laminate components could be strongly reduced by using an intense energy source as well as microwaves. In this work a polyester resin was used with 2% by weight of catalyst and reinforced with chopped or woven glass fabric. Pure resin and composite samples were cured by microwaves exposition for different radiation times. A three point bending test was performed on all the cured samples by using an universal testing machine and the resulting fracture surfaces were observed by means of scanning electron microscopy (SEM). The results of mechanical and microscopy analyses evidenced that microwave activation lowers curing time of the composite while good mechanical properties were retained. Microwaves exposition time is crucial for mechanical performance of the composite. It was evidenced that short exposition times suffice for resin activation while long exposure times cause fast cross linking and premature matrix fracture. Furthermore high-radiation times induce bubbles growth or defects nucleation within the sample, decreasing composite performance. On the basis of such results microwave curing activation of polyester resin based composites could be proposed as a valid alternative method for faster processing of laminated materials employed for large-scale applications.

  9. Quantum gates and memory using microwave-dressed states.

    Science.gov (United States)

    Timoney, N; Baumgart, I; Johanning, M; Varón, A F; Plenio, M B; Retzker, A; Wunderlich, Ch

    2011-08-10

    Trapped atomic ions have been used successfully to demonstrate basic elements of universal quantum information processing. Nevertheless, scaling up such methods to achieve large-scale, universal quantum information processing (or more specialized quantum simulations) remains challenging. The use of easily controllable and stable microwave sources, rather than complex laser systems, could remove obstacles to scalability. However, the microwave approach has drawbacks: it involves the use of magnetic-field-sensitive states, which shorten coherence times considerably, and requires large, stable magnetic field gradients. Here we show how to overcome both problems by using stationary atomic quantum states as qubits that are induced by microwave fields (that is, by dressing magnetic-field-sensitive states with microwave fields). This permits fast quantum logic, even in the presence of a small (effective) Lamb-Dicke parameter (and, therefore, moderate magnetic field gradients). We experimentally demonstrate the basic building blocks of this scheme, showing that the dressed states are long lived and that coherence times are increased by more than two orders of magnitude relative to those of bare magnetic-field-sensitive states. This improves the prospects of microwave-driven ion trap quantum information processing, and offers a route to extending coherence times in all systems that suffer from magnetic noise, such as neutral atoms, nitrogen-vacancy centres, quantum dots or circuit quantum electrodynamic systems.

  10. The influence of differently polarised microwave radiation on chromatin in human cells.

    Science.gov (United States)

    Shckorbatov, Yuriy G; Pasiuga, Vladimir N; Kolchigin, Nicolay N; Grabina, Valentin A; Batrakov, Dmitry O; Kalashnikov, Vladimir V; Ivanchenko, Dmitry D; Bykov, Viktor N

    2009-04-01

    To determine the possible biological effects of differently polarised microwave radiation on the chromatin state in human cells. Isolated human buccal epithelium cells were irradiated by microwaves of frequency f = 35 GHz and surface power density E = 30 microW/cm(2). The state of chromatin in human cells was determined by methods of light and electron microscopy. The state of cell membranes was evaluated by the method of vital indigo carmine staining. The microwave-induced condensation of chromatin in human cells is revealed. Degree of microwave-induced condensation depends on the state of polarisation of electromagnetic wave: In some cases left circularly polarised waves induce less effect than linearly polarised radiation. The linearly polarised electromagnetic waves induce cell membrane damage revealed by increase of cell staining. The data obtained are discussed in connection with mechanisms of biological effects of electromagnetic fields. The data obtained in this work demonstrate important biological effects of monochromatic microwave irradiation at 35 GHz. Low-level microwave irradiation induces chromatin condensation in human cells and damages of cell membranes.

  11. An introduction to abstract algebra

    CERN Document Server

    Robinson, Derek JS

    2003-01-01

    This is a high level introduction to abstract algebra which is aimed at readers whose interests lie in mathematics and in the information and physical sciences. In addition to introducing the main concepts of modern algebra, the book contains numerous applications, which are intended to illustrate the concepts and to convince the reader of the utility and relevance of algebra today. In particular applications to Polya coloring theory, latin squares, Steiner systems and error correcting codes are described. Another feature of the book is that group theory and ring theory are carried further than is often done at this level. There is ample material here for a two semester course in abstract algebra. The importance of proof is stressed and rigorous proofs of almost all results are given. But care has been taken to lead the reader through the proofs by gentle stages. There are nearly 400 problems, of varying degrees of difficulty, to test the reader''s skill and progress. The book should be suitable for students ...

  12. Reconstruction of abstract quantum theory

    International Nuclear Information System (INIS)

    Drieschner, M.; Goernitz, T.; von Weizsaecker, C.F.

    1988-01-01

    Understanding quantum theory as a general theory of prediction, we reconstruct abstract quantum theory. Abstract means the general frame of quantum theory, without reference to a three-dimensional position space, to concepts like particle or field, or to special laws of dynamics. Reconstruction is the attempt to do this by formulating simple and plausible postulates on prediction in order to derive the basic concepts of quantum theory from them. Thereby no law of classical physics is presupposed which would then have to be quantized. We briefly discuss the relationship of theory and interpretation in physics and the fundamental role of time as a basic concept for physics. Then a number of assertions are given, formulated as succinctly as possible in order to make them easily quotable and comparable. The assertations are arranged in four groups: heuristic principles, verbal definitions of some terms, three basic postulates, and consequences. The three postulates of separable alternatives, indeterminism, and kinematics are the central points of this work. These brief assertions are commented upon, and their relationship with the interpretation of quantum theory is discussed. Also given are an outlook on the further development into concrete quantum theory and some philosophical reflections

  13. Influence of the central mode and soft phonon on the microwave dielectric loss near the strain-induced ferroelectric phase transitions in Sr.sub.n+1./sub.Ti.sub.n./sub.O.sub.3n+1./sub..

    Czech Academy of Sciences Publication Activity Database

    Goian, Veronica; Kamba, Stanislav; Orloff, N.; Birol, T.; Lee, Ch.H.; Nuzhnyy, Dmitry; Booth, J.C.; Bernhagen, M.; Uecker, R.; Schlom, D. G.

    2014-01-01

    Roč. 90, č. 17 (2014), "174105-1"-"174105-10" ISSN 1098-0121 R&D Projects: GA MŠk LH13048; GA ČR GAP204/12/1163 Institutional support: RVO:68378271 Keywords : ferroelectrics * microwave properties * central mode * soft mode Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.736, year: 2014

  14. Develop Prototype Microwave Interferometry Diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Tringe, J. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Converse, M. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kane, R. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-11-15

    A prototype microwave interferometer was created at NSTec to characterize moving conductive fronts in upcoming experiments. The interferometer is capable of operation in the ~26-40 GHz band, and interrogating fronts with more than 1 W of power.

  15. Hurricane Satellite (HURSAT) Microwave (MW)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Hurricane Satellite (HURSAT) from Microwave (MW) observations of tropical cyclones worldwide data consist of raw satellite observations. The data derive from the...

  16. Tracking Code for Microwave Instability

    International Nuclear Information System (INIS)

    Heifets, S.; SLAC

    2006-01-01

    To study microwave instability the tracking code is developed. For bench marking, results are compared with Oide-Yokoya results [1] for broad-band Q = 1 impedance. Results hint to two possible mechanisms determining the threshold of instability

  17. The role of the native oxide shell on the microwave sintering of copper metal powder compacts

    International Nuclear Information System (INIS)

    Mahmoud, Morsi M.; Link, Guido; Thumm, Manfred

    2015-01-01

    Highlights: • Thin oxide native layer had a critical role on microwave sintering of copper. • Explain why microwaves interact with copper powder differently than its bulk. • Abnormal expansion in copper is due to the plastic deformation and crack formation. • In-situ setup gives important insight about the microwave sintering of metals. • Microwave sintering is a promising candidate technology in powder metallurgy. - Abstract: Successful microwave sintering of several metal powders had been reported by many researchers with remarkable improvements in the materials properties and/or in the overall process. However, the concept behind microwave heating of metal powders has not been fully understood till now, as it is well known that bulk metals reflect microwaves. The progress of microwave sintering of copper metal powder compacts was investigated via combining both in-situ electrical resistivity and dilatometry measurements that give important information about microstructural changes with respect to the inter-particle electrical contacts during sintering. The sintering behavior of copper metal powders was depending on the type of the gas used, particle size, the initial green density, the soaking sintering time and the thin oxide layer on the particles surfaces. The thin copper oxide native layer (ceramics) that thermodynamically formed on the particles surfaces under normal handling and ambient environmental conditions had a very critical and important role in the microwave absorption and interaction, the sintering behavior and the microstructural changes. This finding could help to have a fundamental understanding of why MW’s interact with copper metal powder in a different way than its bulk at room temperature, i.e. why a given metal powder could be heated using microwaves while its bulk reflects it

  18. Radiological and Environmental Research Division. Annual report. [Lead abstract

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-01-01

    Seventeen papers are presented with abstracts. In addition, five abstracts without papers are included for related topics, i.e., in-vitro inhibition of cell growth; suppression of B.P.-transformed foci in cells; plutonium in drinking water; radioactive properties and biological behavior of radon; and radioactivity and health status of former thorium workers. Two appendices dealing with exposure data for radium patients and radium-induced malignancies are included. (DAD)

  19. Cosmic microwave background, where next?

    CERN Multimedia

    CERN. Geneva

    2009-01-01

    Ground-based, balloon-borne and space-based experiments will observe the Cosmic Microwave Background in greater details to address open questions about the origin and the evolution of the Universe. In particular, detailed observations the polarization pattern of the Cosmic Microwave Background radiation have the potential to directly probe physics at the GUT scale and illuminate aspects of the physics of the very early Universe.

  20. Microwave applications of soft ferrites

    CERN Document Server

    Pardavi-Horvath, M P

    2000-01-01

    Signal processing requires broadband, low-loss, low-cost microwave devices (circulators, isolators, phase shifters, absorbers). Soft ferrites (garnets, spinels, hexaferrites), applied in planar microwave devices, are reviewed from the point of view of device requirements. Magnetic properties, specific to operation in high-frequency electromagnetic fields, are discussed. Recent developments in thick film ferrite technology and device design are reviewed. Magnetic losses related to planar shape and inhomogeneous internal fields are analyzed.

  1. Graphene Josephson Junction Microwave Detector

    Science.gov (United States)

    Fong, Kin Chung; Walsh, Evan; Lee, Gil-Ho; Efetov, Dmitri; Crossno, Jesse; Ranzani, Leonardo; Ohki, Thomas; Kim, Philip; Englund, Dirk

    Modern readout schemes for superconducting qubits have predominately relied on weak microwave signal detection and discrimination. Most schemes are based on heterodyne or homodyne receiver systems and only a few have demonstrated direct detection of microwave photons. The challenges of direct detection stem from the low energy of microwave photons and existing detector efficiency. We have designed, fabricated, and measured a graphene-based Josephson junction (gJJ) microwave detector. Exploiting its low electronic thermal conductivity and specific heat, an electron temperature rise on the order of 0.1 K due to a time average of about 10 photons in the graphene thermal photodetector is readout via a Josephson junction embedded in an 8 GHz microwave cavity. We will estimate the quantum efficiency and dark count probability of the gJJ microwave single photon detectors. This document does not contain technology or technical data controlled under either the U.S. International Traffic in Arms Regulations or the U.S. Export Administration Regulations.

  2. Tunable Multiband Microwave Photonic Filters

    Directory of Open Access Journals (Sweden)

    Mable P. Fok

    2017-11-01

    Full Text Available The increasing demand for multifunctional devices, the use of cognitive wireless technology to solve the frequency resource shortage problem, as well as the capabilities and operational flexibility necessary to meet ever-changing environment result in an urgent need of multiband wireless communications. Spectral filter is an essential part of any communication systems, and in the case of multiband wireless communications, tunable multiband RF filters are required for channel selection, noise/interference removal, and RF signal processing. Unfortunately, it is difficult for RF electronics to achieve both tunable and multiband spectral filtering. Recent advancements of microwave photonics have proven itself to be a promising candidate to solve various challenges in RF electronics including spectral filtering, however, the development of multiband microwave photonic filtering still faces lots of difficulties, due to the limited scalability and tunability of existing microwave photonic schemes. In this review paper, we first discuss the challenges that were facing by multiband microwave photonic filter, then we review recent techniques that have been developed to tackle the challenge and lead to promising developments of tunable microwave photonic multiband filters. The successful design and implementation of tunable microwave photonic multiband filter facilitate the vision of dynamic multiband wireless communications and radio frequency signal processing for commercial, defense, and civilian applications.

  3. Study of federal microwave standards

    Energy Technology Data Exchange (ETDEWEB)

    David, L.

    1980-08-01

    Present and future federal regulatory processes which may impact the permissible levels of microwave radiation emitted by the SPS Microwave Power Transmission (MPTS) were studied. An historical development of US occupational and public microwave standards includes an overview of Western and East European philosophies of environmental protection and neurophysiology which have led to the current widely differing maximum permissible exposure limits to microwaves. The possible convergence of microwave standards is characterized by a lowering of Western exposure levels while Eastern countries consider standard relaxation. A trend toward stricter controls on activities perceived as harmful to public health is under way as is interest in improving the federal regulatory process. Particularly relevant to SPS is the initiation of long-term, low-level microwave exposure programs. Coupled with new developments in instrumentation and dosimetry, the results from chronic exposure program and population exposure studies could be expected within the next five to ten years. Also discussed is the increasing public concern that rf energy is yet another hazardous environmental agent.

  4. The experimental study of the effect of microwave on the physical properties of multi-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Haque, A.K.M. Mahmudul [Department of Ocean System Engineering, Gyeongsang National University, Cheondaegukchi-Gil 38, Tongyeong, Gyeongnam 650-160 (Korea, Republic of); Oh, Geum Seok; Kim, Taeoh [Department of Energy and Mechanical Engineering, Gyeongsang National University, Cheondaegukchi-Gil 38, Tongyeong, Gyeongnam 650-160 (Korea, Republic of); Kim, Junhyo [Department of Marine Engineering, Mokpo National Maritime University Haeyangdaehang-Ro 91, Mokpo-si, Jeollanam-do (Korea, Republic of); Noh, Jungpil; Huh, Sunchul; Chung, Hanshik [Department of Energy and Mechanical Engineering, Gyeongsang National University, Institute of Marine Industry, Cheondaegukchi-Gil 38, Tongyeong, Gyeongnam 650-160 (Korea, Republic of); Jeong, Hyomin, E-mail: hmjeong@gnu.ac.kr [Department of Energy and Mechanical Engineering, Gyeongsang National University, Institute of Marine Industry, Cheondaegukchi-Gil 38, Tongyeong, Gyeongnam 650-160 (Korea, Republic of)

    2016-01-15

    Highlights: • We study the microwave effect on the multi-walled carbon nanotubes (MWCNTs). • We examine the non uniform heating effect on the physical structure of MWCNTs. • We examine the purification of MWCNTs by microwave. • We analyze the thermal characteristics of microwave treated MWCNTs. - Abstract: This paper reports the effect of microwave on the physical properties of multi-walled carbon nanotubes (MWCNTs) where different power levels of microwave were applied on MWCNTs in order to apprehend the effect of microwave on MWCNTs distinctly. A low energy ball milling in aqueous circumstance was also applied on both MWCNTs and microwave treated MWCNTs. Temperature profile, morphological analysis by field emission scanning electron microscopy (FESEM), defect analysis by Raman spectroscopy, thermal conductivity, thermal diffusivity as well as heat transfer coefficient enhancement ratio were studied which expose some strong witnesses of the effect of microwave on the both purification and dispersion properties of MWCNTs in base fluid distilled water. The highest thermal conductivity enhancement (6.06% at 40 °C) of MWCNTs based nanofluid is achieved by five minutes microwave treatment as well as wet grinding at 500 rpm for two hours.

  5. The experimental study of the effect of microwave on the physical properties of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Haque, A.K.M. Mahmudul; Oh, Geum Seok; Kim, Taeoh; Kim, Junhyo; Noh, Jungpil; Huh, Sunchul; Chung, Hanshik; Jeong, Hyomin

    2016-01-01

    Highlights: • We study the microwave effect on the multi-walled carbon nanotubes (MWCNTs). • We examine the non uniform heating effect on the physical structure of MWCNTs. • We examine the purification of MWCNTs by microwave. • We analyze the thermal characteristics of microwave treated MWCNTs. - Abstract: This paper reports the effect of microwave on the physical properties of multi-walled carbon nanotubes (MWCNTs) where different power levels of microwave were applied on MWCNTs in order to apprehend the effect of microwave on MWCNTs distinctly. A low energy ball milling in aqueous circumstance was also applied on both MWCNTs and microwave treated MWCNTs. Temperature profile, morphological analysis by field emission scanning electron microscopy (FESEM), defect analysis by Raman spectroscopy, thermal conductivity, thermal diffusivity as well as heat transfer coefficient enhancement ratio were studied which expose some strong witnesses of the effect of microwave on the both purification and dispersion properties of MWCNTs in base fluid distilled water. The highest thermal conductivity enhancement (6.06% at 40 °C) of MWCNTs based nanofluid is achieved by five minutes microwave treatment as well as wet grinding at 500 rpm for two hours.

  6. Abstract algebra an introductory course

    CERN Document Server

    Lee, Gregory T

    2018-01-01

    This carefully written textbook offers a thorough introduction to abstract algebra, covering the fundamentals of groups, rings and fields. The first two chapters present preliminary topics such as properties of the integers and equivalence relations. The author then explores the first major algebraic structure, the group, progressing as far as the Sylow theorems and the classification of finite abelian groups. An introduction to ring theory follows, leading to a discussion of fields and polynomials that includes sections on splitting fields and the construction of finite fields. The final part contains applications to public key cryptography as well as classical straightedge and compass constructions. Explaining key topics at a gentle pace, this book is aimed at undergraduate students. It assumes no prior knowledge of the subject and contains over 500 exercises, half of which have detailed solutions provided.

  7. Abstract Expression Grammar Symbolic Regression

    Science.gov (United States)

    Korns, Michael F.

    This chapter examines the use of Abstract Expression Grammars to perform the entire Symbolic Regression process without the use of Genetic Programming per se. The techniques explored produce a symbolic regression engine which has absolutely no bloat, which allows total user control of the search space and output formulas, which is faster, and more accurate than the engines produced in our previous papers using Genetic Programming. The genome is an all vector structure with four chromosomes plus additional epigenetic and constraint vectors, allowing total user control of the search space and the final output formulas. A combination of specialized compiler techniques, genetic algorithms, particle swarm, aged layered populations, plus discrete and continuous differential evolution are used to produce an improved symbolic regression sytem. Nine base test cases, from the literature, are used to test the improvement in speed and accuracy. The improved results indicate that these techniques move us a big step closer toward future industrial strength symbolic regression systems.

  8. Algorithmic Approach to Abstracting Linear Systems by Timed Automata

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Wisniewski, Rafael

    2011-01-01

    This paper proposes an LMI-based algorithm for abstracting dynamical systems by timed automata, which enables automatic formal verification of linear systems. The proposed abstraction is based on partitioning the state space of the system using positive invariant sets, generated by Lyapunov...... functions. This partitioning ensures that the vector field of the dynamical system is transversal to all facets of the cells, which induces some desirable properties of the abstraction. The algorithm is based on identifying intersections of level sets of quadratic Lyapunov functions, and determining...

  9. Controlled Microwave Heating Accelerates Rolling Circle Amplification.

    Science.gov (United States)

    Yoshimura, Takeo; Suzuki, Takamasa; Mineki, Shigeru; Ohuchi, Shokichi

    2015-01-01

    Rolling circle amplification (RCA) generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.

  10. Complex-mediated microwave-assisted synthesis of polyacrylonitrile nanoparticles

    Directory of Open Access Journals (Sweden)

    Trinath Biswal

    2010-10-01

    Full Text Available Trinath Biswal, Ramakanta Samal, Prafulla K SahooDepartment of Chemistry, Utkal University, Vani Vihar, Bhubaneswar 751004, IndiaAbstract: The polymerization of acrylonitrile (AN is efficiently, easily, and quickly achieved in the presence of trans-[Co(IIIen2Cl2]Cl complex in a domestic microwave (MW oven. MW irradiation notably promoted the polymerization reaction; this phenomenon is ascribed to the acceleration of the initiator, ammonium persulfate (APS, decomposition by microwave irradiation in the presence of [Co(IIIen2Cl2]Cl. The conversion of monomer to the polymer was mostly excellent in gram scale. Irradiation at low power and time produced more homogeneous polymers with high molecular weight and low polydispersity when compared with the polymer formed by a conventional heating method. The interaction of reacting components was monitored by UV-visible spectrometer. The average molecular weight was derived by gel permeation chromatography (GPC, viscosity methods, and sound velocity by ultrasonic interferometer. The uniform and reduced molecular size was characterized by transmission electron microscopy, the diameter of polyacrylonitrile nanoparticles (PAN being in the range 50–115 nm and 40–230 nm in microwave and conventional heating methods respectively. The surface morphology of PAN prepared by MW irradiation was characterized by scanning electron microscope (SEM. From the kinetic results, the rate of polymerization (Rp was expressed as Rp = [AN]0.63 [APS]0.57 [complex (I].0.88Keywords: microwave, complex catalyst, nanoparticle, kinetics

  11. Preparation and characterization of flexible ferromagnetic nanocomposites for microwave applications

    International Nuclear Information System (INIS)

    Thomas, Teena; Kanoth, Bipinbal P.; Nijas, C.M.; Joy, P.A.; Joseph, Joseph M.; Kuthirummal, Narayanan; Thachil, Eby T.

    2015-01-01

    Highlights: • Fe 3 O 4 nanoparticles (∼20 nm) were synthesised by co-precipitation method. • Nanoparticles were homogeneously distributed in natural rubber through latex stage processing. • Mechanical properties and magnetic properties of composites improved with loading Fe 3 O 4 nanoparticles. • Imaginary part of permeability increases with nanoparticle loading improving the microwave absorption characteristics. • Infrared spectra reveal strong interaction between NR and iron oxide nanoparticles. - Abstract: Magnetic Fe 3 O 4 nanoparticles (∼20 nm) were synthesized using the chemical co-precipitation method with a view of developing flexible and easily processable ferromagnetic materials with high mouldability to be used as microwave absorbers. The nanoparticles prepared were incorporated into natural rubber through latex stage processing. This novel processing method gives better dispersion of particles in the rubber matrix. The composites were characterized using XRD, SEM, vibrating sample magnetometer, dynamic mechanical analyzer, cavity perturbation, thermogravimetry (TGA), and Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS). A notable improvement in the mechanical properties of composites was observed upon adding Fe 3 O 4 particles. Magnetic and microwave characteristics of the composites indicate the formation of a flexible ferromagnetic material with good microwave absorption characteristics

  12. Preparation and characterization of flexible ferromagnetic nanocomposites for microwave applications

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Teena; Kanoth, Bipinbal P. [Department of Polymer Science & Rubber Technology, Cochin University of Science & Technology, Cochin, 682022, Kerala (India); Nijas, C.M. [Department of Electronics, Cochin University of Science & Technology, Cochin, 682022, Kerala (India); Joy, P.A. [Physical and Materials Chemistry Division, National Chemical Laboratory, Pune 411008 (India); Joseph, Joseph M. [Inter University Centre for Nanomaterials and Devices, Cochin University of Science & Technology, Cochin 682022, Kerala (India); Kuthirummal, Narayanan, E-mail: kuthirummaln@cofc.edu [Department of Physics and Astronomy, College of Charleston, Charleston, SC 29424 (United States); Thachil, Eby T., E-mail: ethachil@gmail.com [Department of Polymer Science & Rubber Technology, Cochin University of Science & Technology, Cochin, 682022, Kerala (India)

    2015-10-15

    Highlights: • Fe{sub 3}O{sub 4} nanoparticles (∼20 nm) were synthesised by co-precipitation method. • Nanoparticles were homogeneously distributed in natural rubber through latex stage processing. • Mechanical properties and magnetic properties of composites improved with loading Fe{sub 3}O{sub 4} nanoparticles. • Imaginary part of permeability increases with nanoparticle loading improving the microwave absorption characteristics. • Infrared spectra reveal strong interaction between NR and iron oxide nanoparticles. - Abstract: Magnetic Fe{sub 3}O{sub 4} nanoparticles (∼20 nm) were synthesized using the chemical co-precipitation method with a view of developing flexible and easily processable ferromagnetic materials with high mouldability to be used as microwave absorbers. The nanoparticles prepared were incorporated into natural rubber through latex stage processing. This novel processing method gives better dispersion of particles in the rubber matrix. The composites were characterized using XRD, SEM, vibrating sample magnetometer, dynamic mechanical analyzer, cavity perturbation, thermogravimetry (TGA), and Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS). A notable improvement in the mechanical properties of composites was observed upon adding Fe{sub 3}O{sub 4} particles. Magnetic and microwave characteristics of the composites indicate the formation of a flexible ferromagnetic material with good microwave absorption characteristics.

  13. Surface modification of titanium hydride with epoxy resin via microwave-assisted ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Ning, Rong [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Chen, Ding, E-mail: ma97chen@hotmail.com [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Zhang, Qianxia [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Bian, Zhibing; Dai, Haixiong; Zhang, Chi [Jiangsu Jinling Special Paint Co., Ltd., Yangzhou 225212 (China)

    2014-10-15

    Highlights: • TiH{sub 2} was modified with epoxy resin by microwave-assisted ball milling. • The epoxy ring was opened under the coupling effect of microwave and ball milling. • Microwave-assisted ball milling improved the compatibility of TiH{sub 2} with epoxy. - Abstract: Surface modification of titanium hydride with epoxy resin was carried out via microwave-assisted ball milling and the products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermo-gravimetry (TG) and Fourier transform infrared spectroscopy (FT-IR). A sedimentation test was performed to investigate the compatibility of the modified nano titanium hydride with the epoxy resin. The results show that the epoxy resin molecules were grafted on the surface of nano titanium hydride particles during the microwave-assisted ball milling process, which led to the improvement of compatibility between the nanoparticles and epoxy resin. According to the FT-IR, the grafting site was likely to be located around the epoxy group due to the fact that the epoxy ring was opened. However, compared with microwave-assisted ball milling, the conventional ball milling could not realize the surface modification, indicating that the coupling effect of mechanical force and microwave played a key role during the process.

  14. Anomalous non-resonant microwave absorption in SmFeAs(O,F) polycrystalline sample

    Energy Technology Data Exchange (ETDEWEB)

    Onyancha, R.B., E-mail: 08muma@gmail.com [Department of Physics, College of Science, Engineering and Technology, University of South Africa, Johannesburg, 1710 (South Africa); Shimoyama, J. [Department of Applied Chemistry, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo (Japan); Singh, S.J. [Leibniz-Institute for Solid State and Materials Research, IFW-Dresden, D-01171 Dresden (Germany); Hayashi, K.; Ogino, H. [Department of Applied Chemistry, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo (Japan); Srinivasu, V.V. [Department of Physics, College of Science, Engineering and Technology, University of South Africa, Johannesburg, 1710 (South Africa)

    2017-02-15

    Highlights: • The non-resonant microwave absorption (NRMA) line shape in evolved with microwave power. • Observed a cross over from ‘normal’ absorption to ‘anomalous’ absorption as a function of microwave power. • The anomalous absorption has been explained in the context of non-hysteretic Josephson junction. - Abstract: Here we present the non-resonant microwave absorption (NRMA) studies on SmFeAsO{sub 0.88}F{sub 0.12} polycrystalline sample measured at 6.06 K with the magnetic field swept from −250 G to +250 G at a frequency of 9.45 GHz. It was observed that the (NRMA) line shape evolves as a function of microwave power. Again, the signal intensity increases from 22.83 µW to 0.710 mW where it reaches a maximum and quite remarkably it changed from ‘normal’ absorption to ‘anomalous’ absorption at 2.247 mW, then the intensity decreases with further increase of microwave power. The crossover from ‘normal’ to ‘anomalous’ NRMA absorption and its dependence on microwave power is a new phenomenon in iron pnictides superconductors and we have attributed this anomaly to come from non-hysteretic Josephson junction.

  15. Surface modification of titanium hydride with epoxy resin via microwave-assisted ball milling

    International Nuclear Information System (INIS)

    Ning, Rong; Chen, Ding; Zhang, Qianxia; Bian, Zhibing; Dai, Haixiong; Zhang, Chi

    2014-01-01

    Highlights: • TiH 2 was modified with epoxy resin by microwave-assisted ball milling. • The epoxy ring was opened under the coupling effect of microwave and ball milling. • Microwave-assisted ball milling improved the compatibility of TiH 2 with epoxy. - Abstract: Surface modification of titanium hydride with epoxy resin was carried out via microwave-assisted ball milling and the products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermo-gravimetry (TG) and Fourier transform infrared spectroscopy (FT-IR). A sedimentation test was performed to investigate the compatibility of the modified nano titanium hydride with the epoxy resin. The results show that the epoxy resin molecules were grafted on the surface of nano titanium hydride particles during the microwave-assisted ball milling process, which led to the improvement of compatibility between the nanoparticles and epoxy resin. According to the FT-IR, the grafting site was likely to be located around the epoxy group due to the fact that the epoxy ring was opened. However, compared with microwave-assisted ball milling, the conventional ball milling could not realize the surface modification, indicating that the coupling effect of mechanical force and microwave played a key role during the process

  16. INVESTIGATION OF THERMAL AND NON-THERMAL INTERACTIONS OF MICROWAVES WITH MATERIALS AND MICROWAVE CHEMISTRY

    Directory of Open Access Journals (Sweden)

    Soner KUŞLU

    2002-03-01

    Full Text Available The use of microwaves in industry has generated interest recently as an alternative to classic thermal heating because of the drastic reduction in the processing time. In spite of the fact that there is a wide application of microwaves, the interaction mechanism between microwaves and materials has not been well understood. Nowadays, the fact that there is a debate on the alternative use of microwaves is on not the dielectric heating which is well known but microwave specific effect. In this article there are reports which show similar kinetic in both microwave and classic thermal methods at similar temperature and simple dielectric heating of materials under microwaves conditions. There are also reports which show a clear reaction rate enhancement by microwave radiation compared to the thermal method under similar reactions conditions and temperatures indicating microwave specific effect. In addition, the study on the effects of microwaves on chemical reactions and hypothesis associated with the microwave effects will discuss.

  17. Microwave Sterilization and Depyrogenation System

    Science.gov (United States)

    Akse, James R.; Dahl, Roger W.; Wheeler, Richard R., Jr.

    2009-01-01

    A fully functional, microgravity-compatible microwave sterilization and depyrogenation system (MSDS) prototype was developed that is capable of producing medical-grade water (MGW) without expendable supplies, using NASA potable water that currently is available aboard the International Space Station (ISS) and will be available for Lunar and planetary missions in the future. The microwave- based, continuous MSDS efficiently couples microwaves to a single-phase, pressurized, flowing water stream that is rapidly heated above 150 C. Under these conditions, water is rapidly sterilized. Endotoxins, significant biological toxins that originate from the cell walls of gram-negative bacteria and which represent another defining MGW requirement, are also deactivated (i.e., depyrogenated) albeit more slowly, with such deactivation representing a more difficult challenge than sterilization. Several innovations culminated in the successful MSDS prototype design. The most significant is the antenna-directed microwave heating of a water stream flowing through a microwave sterilization chamber (MSC). Novel antenna designs were developed to increase microwave transmission efficiency. These improvements resulted in greater than 95-percent absorption of incident microwaves. In addition, incorporation of recuperative heat exchangers (RHxs) in the design reduced the microwave power required to heat a water stream flowing at 15 mL/min to 170 C to only 50 W. Further improvements in energy efficiency involved the employment of a second antenna to redirect reflected microwaves back into the MSC, eliminating the need for a water load and simplifying MSDS design. A quick connect (QC) is another innovation that can be sterilized and depyrogenated at temperature, and then cooled using a unique flow design, allowing collection of MGW at atmospheric pressure and 80 C. The final innovation was the use of in-line mixers incorporated in the flow path to disrupt laminar flow and increase contact time

  18. Microwave modulation characteristics of twisted liquid crystals with chiral dopant

    Directory of Open Access Journals (Sweden)

    Rui Yuan

    2017-01-01

    Full Text Available Adding a chiral dopant in twisted nematic (TN liquid crystal cell can stabilize the orientation of liquid crystal molecules, particularly in high TN (HTN or super TN (STN liquid crystal cells. The difference in pitches in liquid crystal is induced by the chiral dopant, and these different pitches affect the orientation of liquid crystal director under an external applied voltage and influence the characteristics of microwave modulation. To illustrate this point, the microwave phase shift per unit length (MPSL versus voltage is calculated on the basis of the elastic theory of liquid crystal and the finite-difference iterative method. Enhancing the pitch induced by the chiral dopant in liquid crystal increases the MPSLs, but the stability of the twisted structures is decreased. Thus, appropriate pitches of 100d, 4d, and 2d can be applied in TN, HTN, and STN cells with cell gap d to enhance the characteristics of microwave modulation and stabilize the structures in twisted cell. This method can improve the characteristics of liquid crystal microwave modulators such that the operating voltage and the size of such phase shifters can be decreased.

  19. Solvothermal synthesis of mesoporous magnetite nanoparticles for Cr(IV) ions uptake and microwave absorption

    KAUST Repository

    Shen, Peng

    2016-05-12

    Abstract: Colloidal mesoporous magnetite nanoparticles with tunable porosity were realized by a simple and scalable solvothermal route with the aid of AOT as ligands. AOT was used to induce the anisotropic crystal growth of smaller nanocrystals and restrain their tight aggregation so as to form more mesoscale pores. Morphologies and microstructures investigation by SEM and TEM revealed that the bigger nanoparticles were composed of smaller nanocrystals with an average size of 18 nm. A possible formation mechanism was proposed for the mesoporous nanoparticles. Study of nitrogen adsorption–desorption isotherm revealed that the Brunauer–Emmett–Teller (BET) specific surface area of mesoporous nanoparticles is up to 209 m2/g, resulting from the slit-shaped pores created by the aggregation of polyhedral nanocrystals. Magnetic properties study indicated that the as-prepared nanoparticles are superparamagnetic at room temperature. Optimized mesoporous magnetite nanoparticles exhibit a maximum Cr(VI) ion sorption capacity of 12.9 mmol/g, and its absorption behavior followed a Freundlich model. Microwave absorption study indicated that porous nanoparticles own higher permeability values than that of solid nanoparticles, leading to a higher dielectric loss in the frequency range of 2–18 GHz. Graphical Abstract: [Figure not available: see fulltext.] © 2016, Springer Science+Business Media Dordrecht.

  20. GA microwave window development

    International Nuclear Information System (INIS)

    Moeller, C.P.; Kasugai, A.; Sakamoto, K.; Takahashi, K.

    1994-10-01

    The GA prototype distributed window was tested in a 32 mm diam. waveguide system at a power density suitable for a MW gyrotron, using the JAERI/Toshiba 110 GHz long pulse internal converter gyrotron in the JAERI test stand. The presence of the untilted distributed window had no adverse effect on the gyrotron operation. A pulse length of 10 times the calculated thermal equilibrium time (1/e time) of 30 msec was reached, and the window passed at least 750 pulses greater than 30 msec and 343 pulses greater than 60 msec. Beyond 100 msec, the window calorimetry reached steady state, allowing the window dissipation to be measured in a single pulse. The measured loss of 4.0% agrees both with the estimated loss, on which the stress calculations are based, and with the attenuation measured at low power in the HE 11 mode. After the end of the tests, the window was examined; no evidence of arcing air coating was found in the part of the window directly illuminated by the microwaves, although there was discoloration in a recess containing an optical diagnostic which outgassed, causing a local discharge to occur in that recess. Finally, there was no failure of the metal-sapphire joints during a total operating time of 50 seconds consisting of pulses longer than 30 msec

  1. A Modal-Logic Based Graph Abstraction

    NARCIS (Netherlands)

    Bauer, J.; Boneva, I.B.; Kurban, M.E.; Rensink, Arend; Ehrig, H; Heckel, R.; Rozenberg, G.; Taentzer, G.

    2008-01-01

    Infinite or very large state spaces often prohibit the successful verification of graph transformation systems. Abstract graph transformation is an approach that tackles this problem by abstracting graphs to abstract graphs of bounded size and by lifting application of productions to abstract

  2. Argonne Code Center: compilation of program abstracts

    International Nuclear Information System (INIS)

    Butler, M.K.; DeBruler, M.; Edwards, H.S.

    1976-08-01

    This publication is the tenth supplement to, and revision of, ANL-7411. It contains additional abstracts and revisions to some earlier abstracts and other pages. Sections of the document are as follows: preface; history and acknowledgements; abstract format; recommended program package contents; program classification guide and thesaurus; and abstract collection

  3. Argonne Code Center: compilation of program abstracts

    International Nuclear Information System (INIS)

    Butler, M.K.; DeBruler, M.; Edwards, H.S.; Harrison, C. Jr.; Hughes, C.E.; Jorgensen, R.; Legan, M.; Menozzi, T.; Ranzini, L.; Strecok, A.J.

    1977-08-01

    This publication is the eleventh supplement to, and revision of, ANL-7411. It contains additional abstracts and revisions to some earlier abstracts and other pages. Sections of the complete document ANL-7411 are as follows: preface, history and acknowledgements, abstract format, recommended program package contents, program classification guide and thesaurus, and the abstract collection

  4. Efficient abstractions for visualization and interaction

    NARCIS (Netherlands)

    van der Ploeg, A.J.

    2015-01-01

    Abstractions, such as functions and methods, are an essential tool for any programmer. Abstractions encapsulate the details of a computation: the programmer only needs to know what the abstraction achieves, not how it achieves it. However, using abstractions can come at a cost: the resulting program

  5. Argonne Code Center: compilation of program abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Butler, M.K.; DeBruler, M.; Edwards, H.S.

    1976-08-01

    This publication is the tenth supplement to, and revision of, ANL-7411. It contains additional abstracts and revisions to some earlier abstracts and other pages. Sections of the document are as follows: preface; history and acknowledgements; abstract format; recommended program package contents; program classification guide and thesaurus; and abstract collection. (RWR)

  6. Argonne Code Center: compilation of program abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Butler, M.K.; DeBruler, M.; Edwards, H.S.; Harrison, C. Jr.; Hughes, C.E.; Jorgensen, R.; Legan, M.; Menozzi, T.; Ranzini, L.; Strecok, A.J.

    1977-08-01

    This publication is the eleventh supplement to, and revision of, ANL-7411. It contains additional abstracts and revisions to some earlier abstracts and other pages. Sections of the complete document ANL-7411 are as follows: preface, history and acknowledgements, abstract format, recommended program package contents, program classification guide and thesaurus, and the abstract collection. (RWR)

  7. EURORIB 2010, Book of abstracts

    International Nuclear Information System (INIS)

    Tsoneva, N.; Lenske, H.; Casten, R.

    2012-01-01

    The second international EURORIB conference 'EURORIB'10' will be held from June 6. to June 11. 2010 in Lamoura (France). Our nuclear physics community is eagerly awaiting the construction of the next generation of Radioactive Ion Beam (RIB) facilities in Europe: HIE-ISOLDE at CERN, NUSTAR at FAIR, SPES at LNL, SPIRAL2 at GANIL and the future EURISOL. The collaborations built around these facilities are exploring new experimental and theoretical ideas that will advance our understanding of nuclear structure through studies of exotic nuclei. Following in the spirit of the conference held in Giens in 2008, EURORIB'10 will provide the opportunity for the different collaborations to come together and present these ideas, and explore the synergy between the research programmes based around the hypothetical severe acprojects. The main topics to be discussed at the conference are: 1) At and beyond the drip line, 2) Shell structure far from stability, 3) Fusion reactions and synthesis of heavy and superheavy nuclei, 4) Dynamics and thermodynamics of exotic nuclear systems, 5) Radioactive ion beams in nuclear astrophysics, 6) New modes of radioactivity, 7) Fundamental interactions, 8) Applications in other fields, 9) Future RIB facilities, 10) Production and manipulation of RIB, and 11) Working group meetings on synergy in instrumentation and data acquisition. This document gathers only the abstracts of the papers. (authors)

  8. WD1145+017 (Abstract)

    Science.gov (United States)

    Motta, M.

    2017-12-01

    (Abstract only) WD1145 is a 17th magnitude white dwarf star 570 light years away in Virgo that was discovered to have a disintegrating planetoid in close orbit by Andrew Vanderburg, a graduate student at Harvard CfA, while data mining the elucidate the nature of its rather bizarre transit light curves. I obtained multiple observations of WD1145 over the course of a year, and found a series of complex transit light curves that could only be interpreted as a ring complex or torus in close orbit around WD1145. Combined with data from other amateur astronomers, professional observations, and satellite data, it became clear that WD1145 has a small planetoid in close orbit at the Roche limit and is breaking apart, forming a ring of debris material that is then raining down on the white dwarf. The surface of the star is "polluted" by heavy metals, determined by spectroscopic data. Given that in the intense gravitational field of a white dwarf any heavy metals could not for long last on the surface, this confirms that we are tracking in real time the destruction of a small planet by its host star.

  9. ABSTRACT MODELS FOR SYSTEM VIRTUALIZATION

    Directory of Open Access Journals (Sweden)

    M. G. Koveshnikov

    2015-05-01

    Full Text Available The paper is dedicated to issues of system objects securing (system files and user system or application configuration files against unauthorized access including denial of service attacks. We have suggested the method and developed abstract system virtualization models, which are used toresearch attack scenarios for different virtualization modes. Estimation for system tools virtualization technology effectiveness is given. Suggested technology is based on redirection of access requests to system objects shared among access subjects. Whole and partial system virtualization modes have been modeled. The difference between them is the following: in the whole virtualization mode all copies of access system objects are created whereon subjects’ requests are redirected including corresponding application objects;in the partial virtualization mode corresponding copies are created only for part of a system, for example, only system objects for applications. Alternative solutions effectiveness is valued relating to different attack scenarios. We consider proprietary and approved technical solution which implements system virtualization method for Microsoft Windows OS family. Administrative simplicity and capabilities of correspondingly designed system objects security tools are illustrated on this example. Practical significance of the suggested security method has been confirmed.

  10. An abstract approach to music.

    Energy Technology Data Exchange (ETDEWEB)

    Kaper, H. G.; Tipei, S.

    1999-04-19

    In this article we have outlined a formal framework for an abstract approach to music and music composition. The model is formulated in terms of objects that have attributes, obey relationships, and are subject to certain well-defined operations. The motivation for this approach uses traditional terms and concepts of music theory, but the approach itself is formal and uses the language of mathematics. The universal object is an audio wave; partials, sounds, and compositions are special objects, which are placed in a hierarchical order based on time scales. The objects have both static and dynamic attributes. When we realize a composition, we assign values to each of its attributes: a (scalar) value to a static attribute, an envelope and a size to a dynamic attribute. A composition is then a trajectory in the space of aural events, and the complex audio wave is its formal representation. Sounds are fibers in the space of aural events, from which the composer weaves the trajectory of a composition. Each sound object in turn is made up of partials, which are the elementary building blocks of any music composition. The partials evolve on the fastest time scale in the hierarchy of partials, sounds, and compositions. The ideas outlined in this article are being implemented in a digital instrument for additive sound synthesis and in software for music composition. A demonstration of some preliminary results has been submitted by the authors for presentation at the conference.

  11. 1986 annual information meeting. Abstracts

    International Nuclear Information System (INIS)

    1986-01-01

    Abstracts are presented for the following papers: Geohydrological Research at the Y-12 Plant (C.S. Haase); Ecological Impacts of Waste Disposal Operations in Bear Creek Valley Near the Y-12 Plant (J.M. Loar); Finite Element Simulation of Subsurface Contaminant Transport: Logistic Difficulties in Handling Large Field Problems (G.T. Yeh); Dynamic Compaction of a Radioactive Waste Burial Trench (B.P. Spalding); Comparative Evaluation of Potential Sites for a High-Level Radioactive Waste Repository (E.D. Smith); Changing Priorities in Environmental Assessment and Environmental Compliance (R.M. Reed); Ecology, Ecotoxicology, and Ecological Risk Assessment (L.W. Barnthouse); Theory and Practice in Uncertainty Analysis from Ten Years of Practice (R.H. Gardner); Modeling Landscape Effects of Forest Decline (V.H. Dale); Soil Nitrogen and the Global Carbon Cycle (W.M. Post); Maximizing Wood Energy Production in Short-Rotation Plantations: Effect of Initial Spacing and Rotation Length (L.L. Wright); and Ecological Communities and Processes in Woodland Streams Exhibit Both Direct and Indirect Effects of Acidification (J.W. Elwood)

  12. Effect of Er{sup 3+} ions on the phase formation and properties of In{sub 2}O{sub 3}nanostructures crystallized upon microwave heating

    Energy Technology Data Exchange (ETDEWEB)

    Lemos, Samantha C.S.; Romeiro, Fernanda C.; Paula, Leonardo F. de [Instituto de Química, Universidade Federal de Uberlândia, 38400-902 Uberlândia, MG (Brazil); Gonçalves, Rosana F. [UNIFESP, Universidade Federal de São Paulo, 09972-270 Diadema, SP (Brazil); Moura, Ana P. de [LIEC, Instituto de Química, Universidade Estadual Paulista, 14800-900 Araraquara, SP (Brazil); Ferrer, Mateus M.; Longo, Elson [INCTMN-UFSCar, Universidade Federal de São Carlos, 13565-905 São Carlos, SP (Brazil); Patrocinio, Antonio Otavio T. [Instituto de Química, Universidade Federal de Uberlândia, 38400-902 Uberlândia, MG (Brazil); Lima, Renata C., E-mail: rclima@ufu.br [Instituto de Química, Universidade Federal de Uberlândia, 38400-902 Uberlândia, MG (Brazil)

    2017-05-15

    Regular sized nanostructures of indium oxide (In{sub 2}O{sub 3}) were homogeneously grown using a facile route, i.e. a microwave-hydrothermal method combined with rapid thermal treatment in a microwave oven. The presence of Er{sup 3+} doping plays an important role in controlling the formation of cubic (bcc) and rhombohedral (rh) In{sub 2}O{sub 3} phases. The samples presented broad photoluminescent emission bands in the green-orange region, which were attributed to the recombination of electrons at oxygen vacancies. The photocatalytic activities of pure bcc-In{sub 2}O{sub 3} and a bcc-rh-In{sub 2}O{sub 3} mixture towards the UVA degradation of methylene blue (MB) were also evaluated. The results showed that Er{sup +3} doped In{sub 2}O{sub 3} exhibited the highest photocatalytic activity with a photonic efficiency three times higher than the pure oxide. The improved performance was attributed to the higher surface area, the greater concentration of electron traps due the presence of the dopant and the possible formation of heterojunctions between the cubic and rhombohedral phases. - Graphical abstract: Photodegradation curves as a function of irradiation time of the samples obtained upon rapid microwave heating. - Highlights: • Efficient and rapid microwave heating to obtain Er{sup 3+} doped In{sub 2}O{sub 3} nanostructures. • Er{sup 3+} ions doping is fundamental to stabilizing the crystalline rhombohedral phase. • Symmetry breaking induced by vacancies in the lattice leads to photoluminescence. • Surface area of doped sample was two times higher than the surface of pure oxide. • The presence of defects in the lattice structure favors photocatalytic activity.

  13. Proceedings of the two days national workshop cum theme meeting on ion beam induced material modifications and neutron generation using 3 MV particle accelerator - applications in physical, chemical and life sciences: souvenir cum abstract book

    International Nuclear Information System (INIS)

    2013-01-01

    The workshop cum theme meeting was planned to identify and have thorough discussion in the area of research that are emerging in the various field of studies using ion beams. The workshop focussed mainly on facilities coming up in the Department of Pure and Applied Physics at Guru Ghasidas Vishwavidyalaya (Central University), Bilaspur in terms of 3 MV accelerator along with online and off-line facilities. These facilities include Ion Beam Implanter, Rutherford Backscattering Spectrometry and Particle Induced X-rays Emission that will be available online and Surface Electron Microscopy, Atomic Force Microscopy, X-ray diffraction, Impedance Spectroscopy, Photoluminescence, Differential Scanning Calorimetry, Fourier Transform Infrared Spectroscopy, UV-VIS Spectrometry, Ferroelectric and Electrical characterization method available in the department for off-line facilities. The major topics discussed in the workshop were: Ion Beam Analysis, Material Synthesis, Modification and Nanostructuring using Energetic Ions, Ion Implantation, Low Energy Accelerator for Neutron Generation, Neutron Induced Reaction Studies and Other Related Topics. The papers relevant to INIS are indexed separately

  14. Microwave assisted polymer stabilized synthesis of silver nanoparticles and its application in the degradation of environmental pollutants

    International Nuclear Information System (INIS)

    Rastogi, Pankaj Kumar; Ganesan, Vellaichamy; Krishnamoorthi, S.

    2012-01-01

    Highlights: ► Graft copolymers of polyacrylamide and dextran are synthesized by grafting PAM chains onto a Dx backbone. ► Silver nanoparticles dispersed copolymer nano-composite (Ag-HDx-g-PAM) is synthesized by microwave heating. ► The environmentally benign and biodegradable copolymer, HDx-g-PAM acts as stabilizing and reducing agent. ► Ag-HDx-g-PAM nano-composite shows efficient catalytic activity for the reduction of environmental pollutants. - Abstract: Graft copolymers of polyacrylamide (PAM) and dextran (Dx) are synthesized by grafting PAM chains onto a Dx backbone (Dx-g-PAM) with ceric ion induced solution polymerization technique. Partial hydrolysis of Dx-g-PAM is carried out with sodium hydroxide solution to obtain HDx-g-PAM. To synthesize silver nanoparticles dispersed copolymer nano-composite (Ag-HDx-g-PAM), reduction of silver ions with HDx-g-PAM is carried out using microwave heating. The environmentally benign and biodegradable copolymer, HDx-g-PAM acts as both stabilizer and reducing agent. The copolymer nano-composite, Ag-HDx-g-PAM is characterized by FT-IR, transmission electron microscopy, scanning electron microscopy and optical spectroscopy. Further, the catalytic activity of Ag-HDx-g-PAM nano-composite towards the reduction of environmental pollutants like phenosafranine dye and aromatic nitro compounds are studied.

  15. Global relation between microwave satellite vegetation products and vegetation productivity

    Science.gov (United States)

    Teubner, Irene E.; Forkel, Matthias; Jung, Martin; Miralles, Diego G.; Dorigo, Wouter A.

    2017-04-01

    The occurrence of unfavourable environmental conditions like droughts commonly reduces the photosynthetic activity of ecosystems and, hence, their potential to take up carbon from the atmosphere. Ecosystem photosynthetic activity is commonly determined using remote sensing observations in the optical domain, which however have limitations particularly in regions of frequent cloud cover, e.g. the tropics. In this study, we explore the potential of vegetation optical depth (VOD) from microwave satellite observations as an alternative source for assessing vegetation productivity. VOD serves as an estimate for vegetation density and water content, which has an impact on plant physiological processes and hence should potentially provide a link to gross primary production (GPP). However, to date, it is unclear how microwave-retrieved VOD data and GPP data are related. We compare seasonal dynamics and anomalies of VOD retrievals from different satellite sensors and microwave frequencies with site level and global GPP estimates. We use VOD observations from active (ASCAT) and passive microwave sensors (AMSR-E, SMOS). We include eddy covariance measurements from the FLUXNET2015 dataset to assess the VOD products at site level. For a global scale analysis, we use the solar-induced chlorophyll fluorescence (SIF) observations from GOME-2 as a proxy for GPP and the FLUXCOM GPP product, which presents an upscaling of site measurements based on remote sensing data. Our results demonstrate that in general a good agreement between VOD and GPP or SIF exists. However, the strength of these relations depends on the microwave frequency, land cover type, and the time within the growing season. Correlations between anomalies of VOD and GPP or SIF support the assumption that microwave-derived VOD can be used to monitor vegetation productivity dynamics. The study is performed as part of the EOWAVE project funded by the Vienna University of Technology (http://eowave.geo.tuwien.ac.at/) and

  16. PET based nanocomposite films for microwave packaging applications

    Energy Technology Data Exchange (ETDEWEB)

    Galdi, M. R., E-mail: mrgaldi@unisa.it; Olivieri, R.; Liguori, L.; Albanese, D., E-mail: dalbanese@unisa.it; Di Matteo, M.; Di Maio, L., E-mail: ldimaio@unisa.it [Industrial Engineering Department, University of Salerno, Via Giovanni Paolo II 132, 84084 Fisciano (Italy)

    2015-12-17

    In recent years, changes in life standards have promoted the diffusion of Ready to Cook (RTC) and Ready to Eat (RTE) products for microwave ovens. However, the main limits in microwave (MW) ovens usage are often related to the proper choice of packaging materials suitable for such technology. In fact, packages for microwaveable RTC and RTE foods should ensure adequate preservation of the product before cooking/heating such as high barriers to gases and aromas and adequate control of water vapor transmission. In addition, microwaveable packaging material must be transparent to MW, thermally stable and resistant to the mechanical stress induced by the accumulation in the head space of volatile substances produced during the cooking. Polymeric materials are good candidates for microwaveable packaging thanks to their transparency to MW. In the last years a great interest is devoted to developing innovative solution based on the use of additives or systems that act as susceptors or heating enhancers for improving the characteristics of polymers in cooking/heating in MW ovens. The present work was focused on the production and characterization of nanocomposite copolyester based films suitable for microwaveable food packaging applications. The matrices selected consist in two PET copolymers modified with carbon black (ULTRA STD) and with titanium oxide (ULTRA NA). Nanocomposite co-extruded multilayer films were produced using different percentages (0%, 2% and 4%wt/wt) of Cloisite 20A (C20A). Films were analyzed for evaluating the effect of nanofiller on the morphology and barrier properties. Moreover, to verify the effectiveness of the designed systems in reducing the cooking times of meat products, MW heating tests were carried out on pork meat hamburgers in MW oven at varying supplied powers. The cooking tests have pointed out that the selected matrices are efficient in reducing cooking times and that even low concentration of C20A acts as heating enhancers of PET.

  17. PET based nanocomposite films for microwave packaging applications

    Science.gov (United States)

    Galdi, M. R.; Olivieri, R.; Liguori, L.; Albanese, D.; Di Matteo, M.; Di Maio, L.

    2015-12-01

    In recent years, changes in life standards have promoted the diffusion of Ready to Cook (RTC) and Ready to Eat (RTE) products for microwave ovens. However, the main limits in microwave (MW) ovens usage are often related to the proper choice of packaging materials suitable for such technology. In fact, packages for microwaveable RTC and RTE foods should ensure adequate preservation of the product before cooking/heating such as high barriers to gases and aromas and adequate control of water vapor transmission. In addition, microwaveable packaging material must be transparent to MW, thermally stable and resistant to the mechanical stress induced by the accumulation in the head space of volatile substances produced during the cooking. Polymeric materials are good candidates for microwaveable packaging thanks to their transparency to MW. In the last years a great interest is devoted to developing innovative solution based on the use of additives or systems that act as susceptors or heating enhancers for improving the characteristics of polymers in cooking/heating in MW ovens. The present work was focused on the production and characterization of nanocomposite copolyester based films suitable for microwaveable food packaging applications. The matrices selected consist in two PET copolymers modified with carbon black (ULTRA STD) and with titanium oxide (ULTRA NA). Nanocomposite co-extruded multilayer films were produced using different percentages (0%, 2% and 4%wt/wt) of Cloisite 20A (C20A). Films were analyzed for evaluating the effect of nanofiller on the morphology and barrier properties. Moreover, to verify the effectiveness of the designed systems in reducing the cooking times of meat products, MW heating tests were carried out on pork meat hamburgers in MW oven at varying supplied powers. The cooking tests have pointed out that the selected matrices are efficient in reducing cooking times and that even low concentration of C20A acts as heating enhancers of PET.

  18. PET based nanocomposite films for microwave packaging applications

    International Nuclear Information System (INIS)

    Galdi, M. R.; Olivieri, R.; Liguori, L.; Albanese, D.; Di Matteo, M.; Di Maio, L.

    2015-01-01

    In recent years, changes in life standards have promoted the diffusion of Ready to Cook (RTC) and Ready to Eat (RTE) products for microwave ovens. However, the main limits in microwave (MW) ovens usage are often related to the proper choice of packaging materials suitable for such technology. In fact, packages for microwaveable RTC and RTE foods should ensure adequate preservation of the product before cooking/heating such as high barriers to gases and aromas and adequate control of water vapor transmission. In addition, microwaveable packaging material must be transparent to MW, thermally stable and resistant to the mechanical stress induced by the accumulation in the head space of volatile substances produced during the cooking. Polymeric materials are good candidates for microwaveable packaging thanks to their transparency to MW. In the last years a great interest is devoted to developing innovative solution based on the use of additives or systems that act as susceptors or heating enhancers for improving the characteristics of polymers in cooking/heating in MW ovens. The present work was focused on the production and characterization of nanocomposite copolyester based films suitable for microwaveable food packaging applications. The matrices selected consist in two PET copolymers modified with carbon black (ULTRA STD) and with titanium oxide (ULTRA NA). Nanocomposite co-extruded multilayer films were produced using different percentages (0%, 2% and 4%wt/wt) of Cloisite 20A (C20A). Films were analyzed for evaluating the effect of nanofiller on the morphology and barrier properties. Moreover, to verify the effectiveness of the designed systems in reducing the cooking times of meat products, MW heating tests were carried out on pork meat hamburgers in MW oven at varying supplied powers. The cooking tests have pointed out that the selected matrices are efficient in reducing cooking times and that even low concentration of C20A acts as heating enhancers of PET

  19. Study of microwave components for an electron cyclotron resonance ...

    Indian Academy of Sciences (India)

    The system consists of a microwave source, an isolator, a directional coupler, a threestub tuner, a high voltage break, a microwave vacuum window, and a microwave launcher. These microwave components were simulated using microwave studio software. The low power and full term characterization of the microwave ...

  20. Microwave. Instructor's Edition. Louisiana Vocational-Technical Education.

    Science.gov (United States)

    Blanton, William

    This publication contains related study assignments and job sheets for a course in microwave technology. The course is organized into 12 units covering the following topics: introduction to microwave, microwave systems, microwave oscillators, microwave modulators, microwave transmission lines, transmission lines, detectors and mixers, microwave…