scholarly journals Reactive Sputtering of NiCr Resistors With Closely Adjustable Temperature Coefficient of Resistance

1977 ◽  
Vol 4 (3-4) ◽  
pp. 133-137 ◽  
Author(s):  
Jürgen Griessing
Keyword(s):  
Heat Treatment ◽  
Temperature Coefficient ◽  
Reactive Sputtering ◽  
Temperature Coefficient Of Resistance ◽  
Term Stability ◽  
Long Term Stability ◽  
Resistor Networks ◽  
Wide Range

A process is described to obtain NiCr resistors with adjustable temperature coefficient of resistance (TCR) by reactive sputtering in an Ar-atmosphere with a small amount of oxygen in the range of 2% to 6%. As deposited the films show a TCR < −200 ppm/K. By heat treatment in air at a temperature of 350°C the TCR can be raised to values above −20 ppm/K. The time of heat treatment necessary to obtain a given TCR depends on the oxygen/argon ratio during sputtering. The long term stability is not affected by the choice of this ratio in a wide range.Resistor networks with a solderable conductor pattern of TiPdAu have a TCR of 0±7 ppm/K and a long term resistance drift ≤ 2‰ in the first 1,000 hours at 125°C.

Long-term stability of ICPCVD a-Si under prolonged heat treatment

2014 ◽  
Author(s):  
Kirsten L. Brookshire ◽  
Mariusz Martyniuk ◽  
K. K. M. B. Dilusha Silva ◽  
Yinong Liu ◽  
Lorenzo Faraone
Keyword(s):  
Heat Treatment ◽  
Term Stability ◽  
Long Term Stability ◽  
Prolonged Heat ◽  
Prolonged Heat Treatment

scholarly journals Experimental Devices to Investigate the Long-Term Stability of Phase Change Materials under Application Conditions

2020 ◽  
Vol 10 (22) ◽  
pp. 7968
Author(s):  
Christoph Rathgeber ◽  
Stefan Hiebler ◽  
Rocío Bayón ◽  
Luisa F. Cabeza ◽  
Gabriel Zsembinszki ◽  
...  
Keyword(s):  
Phase Change ◽  
Thermal Energy ◽  
Phase Change Materials ◽  
Term Stability ◽  
Long Term Stability ◽  
Wide Range ◽  
Solidification Processes ◽  
The Stability ◽  
Solid Liquid

An important prerequisite to select a reliable phase change material (PCM) for thermal energy storage applications is to test it under application conditions. In the case of solid–liquid PCM, a large amount of thermal energy can be stored and released in a small temperature range around the solid–liquid phase transition. Therefore, to test the long-term stability of solid–liquid PCM, they are subjected to melting and solidification processes taking into account the conditions of the intended application. In this work, 18 experimental devices to investigate the long-term stability of PCM are presented. The experiments can be divided into thermal cycling stability tests, tests on PCM with stable supercooling, and tests on the stability of phase change slurries (PCS). In addition to these experiments, appropriate methods to investigate a possible degradation of the PCM are introduced. Considering the diversity of the investigated devices and the wide range of experimental parameters, further work toward a standardization of PCM stability testing is recommended.

scholarly journals Curcumin Containing PEGylated Solid Lipid Nanoparticles for Systemic Administration: A Preliminary Study

Molecules ◽  
2020 ◽  
Vol 25 (13) ◽  
pp. 2991 ◽  
Author(s):  
Debora Santonocito ◽  
Maria Grazia Sarpietro ◽  
Claudia Carbone ◽  
Annamaria Panico ◽  
Agata Campisi ◽  
...  
Keyword(s):  
Zeta Potential ◽  
Solid Lipid Nanoparticles ◽  
Antioxidant Activities ◽  
Lipid Nanoparticles ◽  
Systemic Administration ◽  
Term Stability ◽  
Long Term Stability ◽  
Solid Lipid ◽  
Wide Range

Curcumin (CUR) has a wide range of pharmacological properties, including anti-inflammatory and antioxidant activities, and it can be considered a good candidate for the potential treatment of central nervous system (CNS) pathologies, although its use in clinical practice is compromised due to its high lipophilicity. Solid lipid nanoparticles (SLNs) are well-known nanocarriers representing a consolidated approach for the delivery of lipophilic compounds, but their systemic use is limited due their short half-life. The formulation of stealth SLNs (pSLNs) could be a valid strategy to overcome this limit. Curcumin-loaded-pSLNs were prepared by the solvent evaporation method. Formulation was characterized for their mean size, zeta potential, size distribution, and morphology. Drug antioxidant activity was evaluated by Oxygen Radical Absorbance Capacity (ORAC) assay. Finally, the obtained formulations were analyzed in terms of long-term stability. Curcumin-loaded-pSLNs showed good technological parameters with a mean particle size below 200 nm, as confirmed by TEM images, and a zeta potential value around −30 mV, predicting good long-term stability. Differential Scanning Calorimetry (DSC) analysis confirmed that PEG micelles interacted with the SLN surface; this suggests the location of the PEG on the pSLN surface. Therefore, these preliminary studies suggest that the produced formulation could be regarded as a promising carrier for the systemic administration.

Evaluation of the Long-Term Stability and Temperature Coefficient of Dew-Point Hygrometers

2012 ◽  
Vol 33 (8-9) ◽  
pp. 1758-1770
Author(s):  
R. Benyon ◽  
T. Vicente ◽  
P. Hernández ◽  
L. De Rivas ◽  
F. Conde
Keyword(s):  
Temperature Coefficient ◽  
Dew Point ◽  
Term Stability ◽  
Long Term Stability

scholarly journals Enzymatic Biofuel Cells: A Review on Flow Designs

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 910
Author(s):  
Linda Barelli ◽  
Gianni Bidini ◽  
Dario Pelosi ◽  
Elena Sisani
Keyword(s):  
Power Output ◽  
Wearable Devices ◽  
Operating Conditions ◽  
Biofuel Cells ◽  
Term Stability ◽  
Long Term Stability ◽  
Stage Of Development ◽  
Enzymatic Biofuel Cells ◽  
Wide Range

Because of environmental concerns, there is a growing interest in new ways to produce green energy. Among the several studied applications, enzymatic biofuel cells can be considered as a promising solution to generate electricity from biological catalytic reactions. Indeed, enzymes show very good results as biocatalysts thanks to their excellent intrinsic properties, such as specificity toward substrate, high catalytic activity with low overvoltage for substrate conversion, mild operating conditions like ambient temperature and near-neutral pH. Furthermore, enzymes present low cost, renewability and biodegradability. The wide range of applications moves from miniaturized portable electronic equipment and sensors to integrated lab-on-chip power supplies, advanced in vivo diagnostic medical devices to wearable devices. Nevertheless, enzymatic biofuel cells show great concerns in terms of long-term stability and high power output nowadays, highlighting that this particular technology is still at early stage of development. The main aim of this review concerns the performance assessment of enzymatic biofuel cells based on flow designs, considered to be of great interest for powering biosensors and wearable devices. Different enzymatic flow cell designs are presented and analyzed highlighting the achieved performances in terms of power output and long-term stability and emphasizing new promising fabrication methods both for electrodes and cells.

scholarly journals Long-term stability of marine dissolved organic carbon emerges from a neutral network of compounds and microbes

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
A. Mentges ◽  
C. Feenders ◽  
C. Deutsch ◽  
B. Blasius ◽  
T. Dittmar
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Deep Sea ◽  
Mechanistic Model ◽  
Term Stability ◽  
Long Term Stability ◽  
Heterotrophic Microorganisms ◽  
Wide Range ◽  
The Mean

AbstractDissolved organic carbon (DOC) is the main energy source for marine heterotrophic microorganisms, but a small fraction of DOC resists microbial degradation and accumulates in the ocean. The reason behind this recalcitrance is unknown. We test whether the long-term stability of DOC requires the existence of structurally refractory molecules, using a mechanistic model comprising a diverse network of microbe-substrate interactions. Model experiments reproduce three salient observations, even when all DOC compounds are equally degradable: (i) >15% of an initial DOC pulse resists degradation, but is consumed by microbes if concentrated, (ii) the modelled deep-sea DOC reaches stable concentrations of 30–40 mmolC/m3, and (iii) the mean age of deep-sea DOC is several times the age of deep water with a wide range from <100 to >10,000 years. We conclude that while structurally-recalcitrant molecules exist, they are not required in the model to explain either the amount or longevity of DOC.

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