scholarly journals Ethylene detection in fruit supply chains

2014 ◽  
Vol 372 (2017) ◽  
pp. 20130311 ◽  
Author(s):  
S. Janssen ◽  
K. Schmitt ◽  
M. Blanke ◽  
M. L. Bauersfeld ◽  
J. Wöllenstein ◽  
...  
Keyword(s):  
Supply Chains ◽  
Mobile Application ◽  
Gas Sensing ◽  
Electrochemical Measurement ◽  
Measurement Systems ◽  
Long Term Stability ◽  
Sensing Systems ◽  
Cost Efficient

Ethylene is a gaseous ripening phytohormone of fruits and plants. Presently, ethylene is primarily measured with stationary equipment in laboratories. Applying in situ measurement at the point of natural ethylene generation has been hampered by the lack of portable units designed to detect ethylene at necessary resolutions of a few parts per billion. Moreover, high humidity inside controlled atmosphere stores or containers complicates the realization of gas sensing systems that are sufficiently sensitive, reliable, robust and cost efficient. In particular, three measurement principles have shown promising potential for fruit supply chains and were used to develop independent mobile devices: non-dispersive infrared spectroscopy, miniaturized gas chromatography and electrochemical measurement. In this paper, the measurement systems for ethylene are compared with regard to the needs in fruit logistics; i.e. sensitivity, selectivity, long-term stability, facilitation of automated measurement and suitability for mobile application. Resolutions of 20–10 ppb can be achieved in mobile applications with state-of-the-art equipment, operating with the three methods described in the following. The prices of these systems are in a range below €10 000.

scholarly journals In-Situ Annealed Ti3C2Tx MXene Based All-Solid-State Flexible Zn-Ion Hybrid Micro Supercapacitor Array with Enhanced Stability

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
La Li ◽  
Weijia Liu ◽  
Kai Jiang ◽  
Di Chen ◽  
Fengyu Qu ◽  
...  
Keyword(s):  
High Energy ◽  
High Rate ◽  
High Energy Density ◽  
Electrochemical Performances ◽  
Integrated Electronics ◽  
Long Term Stability ◽  
Hybrid Supercapacitors ◽  
Portable Electronics

AbstractZn-ion hybrid supercapacitors (SCs) are considered as promising energy storage owing to their high energy density compared to traditional SCs. How to realize the miniaturization, patterning, and flexibility of the Zn-ion SCs without affecting the electrochemical performances has special meanings for expanding their applications in wearable integrated electronics. Ti3C2Tx cathode with outstanding conductivity, unique lamellar structure and good mechanical flexibility has been demonstrated tremendous potential in the design of Zn-ion SCs, but achieving long cycling stability and high rate stability is still big challenges. Here, we proposed a facile laser writing approach to fabricate patterned Ti3C2Tx-based Zn-ion micro-supercapacitors (MSCs), followed by the in-situ anneal treatment of the assembled MSCs to improve the long-term stability, which exhibits 80% of the capacitance retention even after 50,000 charge/discharge cycles and superior rate stability. The influence of the cathode thickness on the electrochemical performance of the MSCs is also studied. When the thickness reaches 0.851 µm the maximum areal capacitance of 72.02 mF cm−2 at scan rate of 10 mV s−1, which is 1.77 times higher than that with a thickness of 0.329 µm (35.6 mF cm−2). Moreover, the fabricated Ti3C2Tx based Zn-ion MSCs have excellent flexibility, a digital timer can be driven by the single device even under bending state, a flexible LED displayer of “TiC” logo also can be easily lighted by the MSC arrays under twisting, crimping, and winding conditions, demonstrating the scalable fabrication and application of the fabricated MSCs in portable electronics.

scholarly journals Impact of octreotide counterion nature on the long-term stability and release kinetics from an in situ forming depot technology

2021 ◽  
Vol 336 ◽  
pp. 457-468
Author(s):  
Charlotte Molinier ◽  
Marina Picot-Groz ◽  
Océane Malval ◽  
Sophie Le Lamer-Déchamps ◽  
Joël Richard ◽  
...  
Keyword(s):  
Release Kinetics ◽  
Term Stability ◽  
Long Term Stability ◽  
In Situ Forming ◽  
Counterion Nature

scholarly journals Improved Long‐Term Stability and Reduced Humidity Effect in Gas Sensing: SiO 2 Ultra‐Thin Layered ZnO Columnar Films

2021 ◽  
pp. 2001137
Author(s):  
Vasile Postica ◽  
Oleg Lupan ◽  
Anna Gapeeva ◽  
Luka Hansen ◽  
Rasoul Khaledialidusti ◽  
...  
Keyword(s):  
Gas Sensing ◽  
Humidity Effect ◽  
Term Stability ◽  
Long Term Stability

scholarly journals A single gas chromatograph for accurate atmospheric mixing ratio measurements of CO<sub>2</sub>, CH<sub>4</sub>, N<sub>2</sub>O, SF<sub>6</sub> and CO

2009 ◽  
Vol 2 (2) ◽  
pp. 549-559 ◽  
Author(s):  
S. van der Laan ◽  
R. E. M. Neubert ◽  
H. A. J. Meijer
Keyword(s):  
Research Station ◽  
Time Lags ◽  
Gas Chromatograph ◽  
Efficient System ◽  
Term Stability ◽  
Mixing Ratios ◽  
Long Term Stability ◽  
High Measurement ◽  
Cost Efficient

Abstract. We present an adapted gas chromatograph capable of measuring simultaneously and semi-continuously the atmospheric mixing ratios of the greenhouse gases CO2, CH4, N2O and SF6 and the trace gas CO with high precision and long-term stability. The novelty of our design is that all species are measured with only one device, making it a very cost-efficient system. No time lags are introduced between the measured mixing ratios. The system is designed to operate fully autonomously which makes it ideal for measurements at remote and unmanned stations. Only a small amount of sample air is needed, which makes this system also highly suitable for flask air measurements. In principle, only two reference cylinders are needed for daily operation and only one calibration per year against international WMO standards is sufficient to obtain high measurement precision and accuracy. The system described in this paper is in use since May 2006 at our atmospheric measurement site Lutjewad near Groningen, The Netherlands at 6°21´ E, 53°24´N, 1 m a.s.l. Results show the long-term stability of the system. Observed measurement precisions at our remote research station Lutjewad were: ±0.04 ppm for CO2, ±0.8 ppb for CH4, ±0.8 ppb for CO, ±0.3 ppb for N2O, and ±0.1 ppt for SF6. The ambient mixing ratios of all measured species as observed at station Lutjewad for the period of May 2007 to August 2008 are presented as well.

scholarly journals Slow variations of the Earth’s magnetic field: technical, methodological and organizational features of measurements

2019 ◽  
Vol 127 ◽  
pp. 02026
Author(s):  
Sergey Y. Khomutov
Keyword(s):  
Magnetic Field ◽  
Global Network ◽  
Earth’S Magnetic Field ◽  
Measurement Systems ◽  
Long Term Stability ◽  
Earth's Magnetic Field ◽  
Methodological Problems ◽  
Organizational Features ◽  
Magnetic Observatories

Variations of the Earth’s magnetic field with times of several years or more reflect the processes within the planet and cause great scientific interest. Over the past 100 years the regular observations at magnetic observatories (MOs) and repeat stations are the only experimental basis for studying such variations. In recent decades, satellite measurements have complemented ground-based measurements, thus partially solving the problems of spatially highly heterogeneous global network of magnetic observatories. Absolute observations are made at MOs to get the total field intensity vector. Until now, these measurements are performed manually, they are labor intensity and subject to many factors, that are often poorly controlled and reduce the reliability of the results, especially over long periods of time (years and decades), including (1) systematic errors of used magnetometers; (2) magnetic pollution of the absolute pavilion and its surroundings (at a distance of the first hundred meters); (3) instability of the pillars and remote target required to determine magnetic declination; (4) changes of observers and their weak qualification. Significant methodological problems arise if MO is moved to new location without special activity or infrastructure of MO (pavilions or pillars) is changed without careful control. For long-term stability and reliability of measurements, magnetic observatories were joined in IAGA network and then INTERMAGNET. Within these networks, requirements and standards have been defined, absolute magnetometers are compared every two years and observers are being trained. Modern hardware technologies allow to solve partially problems the automation of absolute observations, the self-calibration of the magnetometers, the checking of the MO’s magnetic environment, etc. Fully automated measurement systems help to expand the MO network.

scholarly journals Middle Ear Transducer: Long Term Stability of the Latest Generation T2

2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
Nils Kristian Prenzler ◽  
Eugen Kludt ◽  
Thomas Giere ◽  
Rolf Salcher ◽  
Thomas Lenarz ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Middle Ear ◽  
Observation Time ◽  
Term Stability ◽  
Long Term Stability ◽  
Average Observation ◽  
Technical Failures

Objectives/Hypothesis. Comparing long term stability of the Middle Ear Transducers (MET) of the 1st generation T1 (Otologics LLC) with the current generation T2 (Cochlear Ltd.) in all our clinical cases with standard incus coupling. Study Design. Retrospective chart review. Methods. 52 ears implanted with a MET device between 2008 and 2016 were analyzed retrospectively. All patients suffered from sensorineural hearing loss and the actuator was coupled to the body of the incus (standard coupling). 23 ears were implanted with the transducer T1 (Otologics LLC) between 2008 and 2011 and 29 ears were implanted with the current transducer T2 since 2011 (Otologics LLC/Cochlear Ltd.). Latest available in situ and bone conduction (BC) thresholds were exploited for a follow-up period of up to 7 years after first fitting. Long term stability of coupling and actuator performance was evaluated by tracking differences between in situ and BC thresholds. Results. In the T1 group, 9 out of 23 implants were still used by the patients at their last follow-up visit (average observation time 3.7 yrs.; min 1.0 yrs., max 7.4 yrs.). In 9 patients a technical failure identified by a decrease of in situ threshold of more than 15 dB compared to BC thresholds [Δ (in situ – BC)] lead to non-usage of the implant and 7 explantations. Five other explantations occurred due to medical reasons such as BC threshold decrease, infection, or insufficient speech intelligibility with the device. In the T2 group, 23 out of 29 implants were still used at the most current follow-up visit (average observation time 3.3 yrs.; min 1.0 yrs., max 4.8 yrs.). No technical failures were observed up to more than 4 years after implantation. Five T2 patients discontinued using the device due to insufficient benefit; two of these patients were explanted. One patient had to be explanted before the activation of the device due to disorders of wound healing. Nevertheless, a small but significant decrease of hearing loss corrected coupling efficiency [Δ (in situ – BC)] was seen in the T2 group. Conclusions. In contrast to the T1 transducers of the earlier generation of MET systems where technical failures occurred frequently, no technical failures were detected after 29 implantations with the current T2 transducers. However, a small but significant decline of transmission efficiency was observable even in the T2 implanted group.

Reduction of bioaccessibility of As in soil through in situ formation of amorphous Fe oxides and its long-term stability

2020 ◽  
Vol 745 ◽  
pp. 140989
Author(s):  
Jinhee Park ◽  
Jinsung An ◽  
Hyeonyong Chung ◽  
Sang Hyun Kim ◽  
Kyoungphile Nam
Keyword(s):  
Term Stability ◽  
Long Term Stability ◽  
Fe Oxides ◽  
In Situ Formation

scholarly journals Enhanced Methane Sensing Properties of WO3 Nanosheets with Dominant Exposed (200) Facet via Loading of SnO2 Nanoparticles

Nanomaterials ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 351 ◽  
Author(s):  
Dongping Xue ◽  
Junjun Wang ◽  
Yan Wang ◽  
Guang Sun ◽  
Jianliang Cao ◽  
...  
Keyword(s):  
Gas Sensing ◽  
Defect Density ◽  
Sno2 Nanoparticles ◽  
High Reactivity ◽  
Optimum Operating ◽  
Optimum Operating Temperature ◽  
Sensing Properties ◽  
Long Term Stability ◽  
Subsequent Calcination

Methane detection is extremely difficult, especially at low temperatures, due to its high chemical stability. Here, WO3 nanosheets loaded with SnO2 nanoparticles with a particle size of about 2 nm were prepared by simple impregnation and subsequent calcination using SnO2 and WO3·H2O as precursors. The response of SnO2-loaded WO3 nanosheet composites to methane is about 1.4 times higher than that of pure WO3 at the low optimum operating temperature (90 °C). Satisfying repeatability and long-term stability are ensured. The dominant exposed (200) crystal plane of WO3 nanosheets has a good balance between easy oxygen chemisorption and high reactivity at the dangling bonds of W atoms, beneficial for gas-sensing properties. Moreover, the formation of a n–n type heterojunction at the SnO2-WO3 interface and additionally the increase of specific surface area and defect density via SnO2 loading enhance the response further. Therefore, the SnO2-WO3 composite is promising for the development of sensor devices to methane.

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