Instruments

8 pages, 7661 KiB

Open AccessCommunication

Monitoring Moisture Content for Various Kind of Tea Leaves in Drying Processes Using RF Reflectometer-Sensor System

by Kok Yeow You, Chia Yew Lee, Kok San Chan, Kim Yee Lee, Ee Meng Cheng and Yeng Seng Lee

Instruments 2018, 2(3), 18; https://doi.org/10.3390/instruments2030018 - 17 Sep 2018

Cited by 9 | Viewed by 6830

This paper presents tea leaves moisture monitoring system based on RF reflectometry techniques. The system was divided into two parts which are the sensor and reflectometer parts. The large coaxial probe was used as a sensor for the system. The reflectometer part plays [...] Read more.

This paper presents tea leaves moisture monitoring system based on RF reflectometry techniques. The system was divided into two parts which are the sensor and reflectometer parts. The large coaxial probe was used as a sensor for the system. The reflectometer part plays a role as signal generator and also data acquisition. The reflectometer-sensor system was operated with a graphical user interface at 1.529 GHz at room temperature. The system was able to measure the moisture content of tea leaves ranging 0% m.c to 50% m.c on a wet basis. In this study, up to five kinds of tea leaves bulk were tested. The mean of absolute errors in the moisture measurement for tea leaves was ±2. Full article

(This article belongs to the Special Issue Advanced Instrumentation for an Intelligent Agriculture: Current Trends and Perspectives)

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9 pages, 2241 KiB

Open AccessArticle

Automated Purification of Radiometals Produced by Liquid Targets

by Vítor H. Alves, Sérgio J. C. Do Carmo, Francisco Alves and Antero J. Abrunhosa

Instruments 2018, 2(3), 17; https://doi.org/10.3390/instruments2030017 - 14 Sep 2018

Cited by 26 | Viewed by 5664

Abstract

An automated process for the production and purification of radiometals produced by irradiating liquid targets in a medical cyclotron, using a commercially available module, has been developed. The method is suitable for the production and purification of radiometals such as ⁶⁸Ga, ⁶⁴ [...] Read more.

An automated process for the production and purification of radiometals produced by irradiating liquid targets in a medical cyclotron, using a commercially available module, has been developed. The method is suitable for the production and purification of radiometals such as ⁶⁸Ga, ⁶⁴Cu and ⁶¹Cu through irradiation of liquid targets and is important for producing high specific activity radioisotopes with a substantial reduction in processing time and cost when compared with the solid target approach. The “liquid target” process also eliminates the need for pre- and post-irradiation target preparation and simplifies the transfer of irradiated material from target to hotcell. A ⁶⁸GaCl₃ solution can be obtained in about 35 min with an average yield of 73.9 ± 6.7% in less than 10 mL of volume. ⁶⁴CuCl₂ solutions can be obtained with an average yield of 81.2 ± 7.8% in about 1 h of processing time. A dedicated single-use disposable kit is used on a commercial IBA Synthera^® extension module. Full article

(This article belongs to the Special Issue Instruments and Methods for Cyclotron Produced Radioisotopes)

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16 pages, 5272 KiB

Open AccessArticle

Hardware Design of a High Dynamic Range Radio Frequency (RF) Harmonic Measurement System

by Ram M. Narayanan, Kyle A. Gallagher, Gregory J. Mazzaro, Anthony F. Martone and Kelly D. Sherbondy

Instruments 2018, 2(3), 16; https://doi.org/10.3390/instruments2030016 - 19 Aug 2018

Cited by 12 | Viewed by 4765

Abstract

Radio frequency (RF) circuit elements that are traditionally considered to be linear frequently exhibit nonlinear properties that affect the intended operation of many other RF systems. Devices such as RF connectors, antennas, attenuators, resistors, and dissimilar metal junctions generate nonlinear distortion that degrades [...] Read more.

Radio frequency (RF) circuit elements that are traditionally considered to be linear frequently exhibit nonlinear properties that affect the intended operation of many other RF systems. Devices such as RF connectors, antennas, attenuators, resistors, and dissimilar metal junctions generate nonlinear distortion that degrades primary RF system performance. The communications industry is greatly affected by these unintended and unexpected nonlinear distortions. The high transmit power and tight channel spacing of the communication channel makes communications very susceptible to nonlinear distortion. To minimize nonlinear distortion in RF systems, specialized circuits are required to measure the low level nonlinear distortions created from traditionally linear devices, i.e., connectors, cables, antennas, etc. Measuring the low-level nonlinear distortion is a difficult problem. The measurement system requires the use of high power probe signals and the capability to measure very weak nonlinear distortions. Measuring the weak nonlinear distortion becomes increasingly difficult in the presence of higher power probe signals, as the high power probe signal generates distortion products in the measurement system. This paper describes a circuit design architecture that achieves 175 dB of dynamic range which can be used to measure low level harmonic distortion from various passive RF circuit elements. Full article

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23 pages, 8188 KiB

Open AccessArticle

First Steps at the Cyclotron of Orléans in the Radiochemistry of Radiometals: ⁵²Mn and ¹⁶⁵Er

by Justine Vaudon, Louis Frealle, Geoffrey Audiger, Elodie Dutillly, Mathieu Gervais, Emmanuel Sursin, Charlotte Ruggeri, Florian Duval, Marie-Laure Bouchetou, Aude Bombard and Isidro Da Silva

Instruments 2018, 2(3), 15; https://doi.org/10.3390/instruments2030015 - 16 Aug 2018

Cited by 7 | Viewed by 4720

Abstract

This work describes the first real developments in radiochemistry around exotic radionuclides at the cyclotron of Orléans focusing on the radiochemistry of two radiometals ¹⁶⁵Er and ⁵²Mn. For these developments, targets were irradiated during 0.5–2 h at a maximum current of [...] Read more.

This work describes the first real developments in radiochemistry around exotic radionuclides at the cyclotron of Orléans focusing on the radiochemistry of two radiometals ¹⁶⁵Er and ⁵²Mn. For these developments, targets were irradiated during 0.5–2 h at a maximum current of 2 µA. All activities have been determined by radiotracer method. The production of ¹⁶⁵Er from a natural Ho target that was irradiated is described. Higher activities of ¹⁶⁵Er were obtained via deuteron irradiation then proton with lower ratio ¹⁶⁵Er/¹⁶⁶Ho (400/1 to 8/1). By using LN2 resin, the separation of adjacent lanthanides was made on various concentrations of HNO₃ (0.3 to 5 M). Weight coefficients (Dw) were defined in a batch test. Then, the first tests of separation on a semi-automated system were made: the ratio ^166+natHo/¹⁶⁵Er in an isolated fraction was significantly reduced (1294 ± 1183 (n = 3)) but the reliability and reproducibility of the system must be improved. Then, a new Cr powder-based target for ⁵²Mn production was designed. Its physical aspects such as mechanics, thermal resistance and porosity have been studied. Dw for various compositions of eluent Ethanol/HCl were evaluated by reducing contact time (1 h) comparative to the literature. A first evaluation of semi-automated separation Cr/Mn has been made. Full article

(This article belongs to the Special Issue Instruments and Methods for Cyclotron Produced Radioisotopes)

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7 pages, 4325 KiB

Open AccessArticle

Plasma Deflection Interrupter for Pulsed Power Applications

by Nathan Majernik, Walter Lynn, Yusuke Sakai and James Rosenzweig

Instruments 2018, 2(3), 14; https://doi.org/10.3390/instruments2030014 - 29 Jul 2018

Viewed by 3274

Abstract

A plasma-based opening switch, capable of handling kiloampere currents at kilovolt potentials on the microsecond timescale, is described and characterized. The principle of operation is the deflection of a laser-induced arc by an external magnetic field to a shunt circuit path. A first-order [...] Read more.

A plasma-based opening switch, capable of handling kiloampere currents at kilovolt potentials on the microsecond timescale, is described and characterized. The principle of operation is the deflection of a laser-induced arc by an external magnetic field to a shunt circuit path. A first-order model of operation is introduced. Finally, the merits of the device, particularly when applied to high-repetition-rate dense plasma focus (DPF) systems, are discussed. Full article

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10 pages, 1814 KiB

Open AccessArticle

A Simple Electrostatic Device for Eliminating Tobacco Sidestream Smoke to Prevent Passive Smoking

by Yoshinori Matsuda, Koji Kakutani, Teruo Nonomura, Yoshihiro Takikawa, Kiyotsugu Okada, Manabu Shibao, Kazuhiro Miyama, Shinya Yokoo, Shin-ichi Kusakari and Hideyoshi Toyoda

Instruments 2018, 2(3), 13; https://doi.org/10.3390/instruments2030013 - 22 Jul 2018

Cited by 9 | Viewed by 4596

Abstract

An electrostatic apparatus was constructed to capture tobacco sidestream smoke. This apparatus consisted of a perforated polypropylene plate with metal spikes and a grounded metal net arrayed in parallel at a defined interval. Spikes were negatively charged to positively polarize the net and [...] Read more.

An electrostatic apparatus was constructed to capture tobacco sidestream smoke. This apparatus consisted of a perforated polypropylene plate with metal spikes and a grounded metal net arrayed in parallel at a defined interval. Spikes were negatively charged to positively polarize the net and an electric field was formed between the opposite charges of the spike tips and the grounded net. Discharge from the spike tips occurred, which depended on the pole distance and the voltage applied to the spikes. At lower voltages (<12.1 kV) that do not cause arc discharge from the tips, a corona discharge occurred with the generation of an ionic wind from the spiked plate to the net. This discharge increased in direct proportion to the applied voltage and relative humidity, while a larger corona discharge generated a stronger ionic wind. The ionic wind involved negative ions and the number of negative ions in the wind increased with increasing applied voltage. The optimal voltage (10 kV) generated sufficient negative ions to ionize smoke particles in the electric field, before the ionized smoke particles were successfully captured by the oppositely charged metal net. Thus, this study provides an experimental basis for the practical application of an electrostatic-based method to prevent the production of tobacco sidestream smoke that leads to passive smoking by non-smokers. Full article

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8 pages, 1552 KiB

Open AccessArticle

Optimized Treatment and Recovery of Irradiated [¹⁸O]-Water in the Production of [¹⁸F]-Fluoride

by Antje Uhlending, Harald Henneken, Verena Hugenberg and Wolfgang Burchert

Instruments 2018, 2(3), 12; https://doi.org/10.3390/instruments2030012 - 4 Jul 2018

Cited by 2 | Viewed by 3608

Abstract

Enriched [¹⁸O]-water is the target material for [¹⁸F]-fluoride production. Due to its high price and scarce availability, an increased interest and necessity has arisen to recycle the used water, in order to use it multiple times as a target [...] Read more.

Enriched [¹⁸O]-water is the target material for [¹⁸F]-fluoride production. Due to its high price and scarce availability, an increased interest and necessity has arisen to recycle the used water, in order to use it multiple times as a target material for [¹⁸F]-fluoride production. This paper presents an efficient treatment and reprocessing procedure giving rise to high chemical quality [¹⁸O]-water, thereby maintaining its enrichment grade. The reprocessing is subdivided into two main steps. In the first step, the [¹⁸F]-FDG (fluorodeoxyglucose) synthesis preparation was modified to preserve the enrichment grade. Anhydrous acetonitrile is used to dry tubing systems and cartridges in the synthesis module. Applying this procedure, the loss in the enrichment throughout the reprocessing is <1%. The second step involves a fractional distillation in which the major part of the [¹⁸O]-water was recycled. Impurities such as solvents, ions, and radioactive nuclides were almost completely separated. Due to the modified synthesis preparation using acetonitrile, the first distillation fraction contains a larger amount of an azeotropic [¹⁸O]-water/acetonitrile mixture. This fraction is not further distillable. Contents of the remaining [¹⁸O]-water were separated from the azeotropic mixture by using a molecular sieve desiccant. This process represents a fast, easy, and inexpensive method for reprocessing used [¹⁸O]-water into new [¹⁸O]-water quality for further application. Full article

(This article belongs to the Special Issue Instruments and Methods for Cyclotron Produced Radioisotopes)

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10 pages, 4415 KiB

Open AccessArticle

PaddyCheck—An Instrument for Rice Quality Determination

by Jeanette Purhagen, Raivo Loosme, Nils Wihlborg, Jenny Fjällström, Peter Åberg, Henrik Andrén, Gunnel Wihlborg, Torbjörn Mikaelsson, Martin Lagerholm and Frans Lindwall

Instruments 2018, 2(3), 11; https://doi.org/10.3390/instruments2030011 - 3 Jul 2018

Cited by 5 | Viewed by 9611

Abstract

Several of the rice quality parameters are nowadays determined manually or partly manually, which leads to subjective results. In order to analyse the rice quality and avoid most of the manual handling, the PaddyCheck instrument was mainly developed to measure the paddy/rough rice [...] Read more.

Several of the rice quality parameters are nowadays determined manually or partly manually, which leads to subjective results. In order to analyse the rice quality and avoid most of the manual handling, the PaddyCheck instrument was mainly developed to measure the paddy/rough rice kernels. However, the design and technique of the instrument are also suitable for brown rice kernels. The PaddyCheck instrument measures the physical properties of the rice kernels as well as texture properties and translucency. Initial calibrations have been developed to correlate these properties with the Head Rice Yield and Chalkiness, which are two of the most common and important quality parameters for rice. Full article

(This article belongs to the Special Issue Advanced Instrumentation for an Intelligent Agriculture: Current Trends and Perspectives)

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10 pages, 1107 KiB

Open AccessFeature PaperArticle

High Efficiency Cyclotron Trap Assisted Positron Moderator

by Lars Gerchow, Saverio Braccini, Tommaso Stefano Carzaniga, David Cooke, Max Döbeli, Klaus Kirch, Ulli Köster, Arnold Müller, Nicholas P. Van der Meulen, Christiaan Vermeulen, André Rubbia and Paolo Crivelli

Instruments 2018, 2(3), 10; https://doi.org/10.3390/instruments2030010 - 28 Jun 2018

Cited by 3 | Viewed by 5030

Abstract

We report on the realisation of a cyclotron trap assisted positron tungsten moderator for the conversion of positrons with a broad keV–few MeV energy spectrum to a mono-energetic eV beam with an efficiency of 1.8(2)% defined as the ratio of the slow positrons [...] Read more.

We report on the realisation of a cyclotron trap assisted positron tungsten moderator for the conversion of positrons with a broad keV–few MeV energy spectrum to a mono-energetic eV beam with an efficiency of 1.8(2)% defined as the ratio of the slow positrons divided by the

β^{+}

activity of the radioactive source. This is an improvement of almost two orders of magnitude compared to the state of the art of tungsten moderators. The simulation validated with this measurement suggests that, using an optimised setup, even higher efficiencies are achievable. A novel method for the production of

^{48}

V high-activity thin foil positron sources based on a solid target station at a medical cyclotron was developed. This is an improvement of more than one order of magnitude with respect to standard methods. Full article

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Graphical abstract

7 pages, 3053 KiB

Open AccessArticle

A Target-Temperature Monitoring System for Cyclotron Targets: Safety Device and Tool to Experimentally Validate Targetry Studies

by Sergio J. C. Do Carmo, Pedro M. De Oliveira and Francisco Alves

Instruments 2018, 2(3), 9; https://doi.org/10.3390/instruments2030009 - 21 Jun 2018

Cited by 2 | Viewed by 3562

Abstract

The present work describes an experimental system enabling temperature measurement in cyclotron targets’ cooling water during bombardment. The developed system provides sensible and immediate response to variations of irradiation conditions during bombardment and enables quantification of the temperature rise in the cooling water [...] Read more.

The present work describes an experimental system enabling temperature measurement in cyclotron targets’ cooling water during bombardment. The developed system provides sensible and immediate response to variations of irradiation conditions during bombardment and enables quantification of the temperature rise in the cooling water due to beam interaction with the irradiated target and with its collimator. Such a system finds application either as a monitoring safety device to instantaneously detect and register abnormal alterations in target conditions to anticipate thermal-related incidents and as a tool to experimentally validate cyclotron targetry optimization studies and thermal simulations. Full article

(This article belongs to the Special Issue Instruments and Methods for Cyclotron Produced Radioisotopes)

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Instruments, Volume 2, Issue 3 (September 2018) – 10 articles

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