scholarly journals Investigations on the Performance of Various Horizontal Ground Electrodes

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1036
Author(s):  
Hanis Hamizah Hizamul-Din ◽  
Normiza Mohamad Nor ◽  
Nurul Nadia Ahmad ◽  
Nur Farahi Idris ◽  
Azwan Mahmud
Keyword(s):  
Steady State ◽  
Electric Field ◽  
Field Enhancement ◽  
Field Measurements ◽  
Ionization Process ◽  
Ionization Zone ◽  
Cross Sectional ◽  
Air Voids ◽  
Time To Peak ◽  
Set Up

Experimental work on grounding systems has shown that the characteristics of grounding systems under high impulse conditions are different than those obtained at steady-state conditions. Investigations on the grounding systems under high impulse conditions make it evident that ionization process could occur in soil, due to field enhancement in air voids in the soil. This process can lead to an ionization zone that reduces the impulse resistance of grounding systems (due to an enlargement of a virtually increased cross-sectional area) from its steady state. There have been many studies pointing towards the effect of various soils and the ground electrode’s arrangement on the reduction of impulse resistance from its steady state, and its decrease with increasing currents. It was, however, noted that very few studies on the effect of the configurations of horizontal ground electrodes have been performed by field measurements before. This work presents the experimental and simulated work of various configurations of ground electrodes, with spikes which are thought to enhance the ionization process in soil. In this paper, field measurement was set up, and the results of field measurements were applied with finite element method (FEM) to obtain the electric field values. It was demonstrated that with the addition of spike on the electrodes, a high electric field was computed. The time to peak current, discharged time and impulse impedance were also analyzed for various horizontal ground electrodes.

scholarly journals Driver versus navigator causation in biology: the case of insulin and fasting glucose

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10396
Author(s):  
Manawa Diwekar-Joshi ◽  
Milind Watve
Keyword(s):  
Systematic Review ◽  
Steady State ◽  
Insulin Action ◽  
Causal Relation ◽  
State Level ◽  
Epidemiological Data ◽  
Cross Sectional ◽  
Glucose Levels ◽  
Clinical Action ◽  
Set Up

Background In biomedicine, inferring causal relation from experimental intervention or perturbation is believed to be a more reliable approach than inferring causation from cross-sectional correlation. However, we point out here that even in interventional inference there are logical traps. In homeostatic systems, causality in a steady state can be qualitatively different from that in a perturbed state. On a broader scale there is a need to differentiate driver causality from navigator causality. A driver is essential for reaching a destination but may not have any role in deciding the destination. A navigator on the other hand has a role in deciding the destination and the path but may not be able to drive the system to the destination. The failure to differentiate between types of causalities is likely to have resulted into many misinterpretations in physiology and biomedicine. Methods We illustrate this by critically re-examining a specific case of the causal role of insulin in glucose homeostasis using five different approaches (1) Systematic review of tissue specific insulin receptor knock-outs, (2) Systematic review of insulin suppression and insulin enhancement experiments, (3) Differentiating steady state and post-meal state glucose levels in streptozotocin treated rats in primary experiments, (4) Mathematical and theoretical considerations and (5) Glucose-insulin relationship in human epidemiological data. Results All the approaches converge on the inference that although insulin action hastens the return to a steady state after a glucose load, there is no evidence that insulin action determines the steady state level of glucose. Insulin, unlike the popular belief in medicine, appears to be a driver but not a navigator for steady state glucose level. It is quite likely therefore that the current line of clinical action in the field of type 2 diabetes has limited success largely because it is based on a misinterpretation of glucose-insulin relationship. The insulin-glucose example suggests that we may have to carefully re-examine causal inferences from perturbation experiments and set up revised norms for experimental design for causal inference.

Studies in electrohydrodynamics. I. The circulation produced in a drop by an electric field

1966 ◽  
Vol 291 (1425) ◽  
pp. 159-166 ◽  
Keyword(s):  
Dielectric Constant ◽  
Steady State ◽  
Electric Field ◽  
Dielectric Fluid ◽  
Uniform Field ◽  
Theoretical Predictions ◽  
Set Up ◽  
Surrounding Fluid

The elongation of a drop of one dielectric fluid in another owing to the imposition of an electric field has previously been studied assuming that the interface is uncharged and the fluids at rest. For a steady field this is unrealistic, because however small the conductivity of either fluid the charge associated with steady currents must accumulate at the interface till the steady state is established. It is shown that equilibrium can only be established in a drop when circulations are set up both in the drop and its surroundings. A relation is found between the ratios of the conductivity, viscosity and dielectric constant for the drop and surrounding fluid which permits the drop to remain spherical when subjected to a uniform field. The streamlines of the circulation for this case are shown and criteria are given for distinguishing between circulations which carry the surface of the drop towards or away from the poles and for predicting whether the drop will become prolate or oblate. Experiments by S. G. Mason and his co-workers are compared with the theoretical predictions and agreement is found in all cases for which the necessary data are given.

Electrohydrodynamics of a liquid drop: the development of the flow field

1973 ◽  
Vol 334 (1598) ◽  
pp. 343-356 ◽  
Keyword(s):  
Steady State ◽  
Flow Field ◽  
Electric Field ◽  
Liquid Drop ◽  
Drop Surface ◽  
Steady State Flow ◽  
Field Stress ◽  
State Flow ◽  
Developing Flow ◽  
Set Up

In this paper we consider the development of the flow field in and about a liquid drop immersed in a conducting fluid, induced by an electric field stress. We place special emphasis to the case when the applied electric field is a d.c. field. We assume that the electric field stress is set up instantaneously and investigate the development of the flow field as the drop is being deformed. Thus, the present work is an extension of Sir Geoffrey Taylor’s work concerning the steady state flow field set up by a d.c. field and the author’s work concerning the quasi-steady state flow generated by an a.c. field. In the case of a d.c. field, the fluid circulation in the proximity of the drop surface initially forms closed loops which eventually propagate to infinity. Also, in the proximity of the drop surface, the developing flow field may be more intense and even directed in opposite sense in comparison with that of the steady state. In the limit, when the time t tends to infinity, the solution presented here converges to the solutions established in the papers referred to above.

Conflict Avoidance in Old Age

GeroPsych ◽  
2017 ◽  
Vol 30 (2) ◽  
pp. 61-70 ◽  
Author(s):  
Lia Oberhauser ◽  
Andreas B. Neubauer ◽  
Eva-Marie Kessler
Keyword(s):  
Social Support ◽  
Perceived Social Support ◽  
Well Being ◽  
Cross Sectional Study ◽  
Conflict Avoidance ◽  
Subjective Well Being ◽  
Sectional Study ◽  
Cross Sectional ◽  
Adult Lifespan ◽  
Set Up

Abstract. Conflict avoidance increases across the adult lifespan. This cross-sectional study looks at conflict avoidance as part of a mechanism to regulate belongingness needs ( Sheldon, 2011 ). We assumed that older adults perceive more threats to their belongingness when they contemplate their future, and that they preventively react with avoidance coping. We set up a model predicting conflict avoidance that included perceptions of future nonbelonging, termed anticipated loneliness, and other predictors including sociodemographics, indicators of subjective well-being and perceived social support (N = 331, aged 40–87). Anticipated loneliness predicted conflict avoidance above all other predictors and partially mediated the age-association of conflict avoidance. Results suggest that belongingness regulation accounts may deepen our understanding of conflict avoidance in the second half of life.

Association of CYP2D6*10 (c. 100 C>T) Genotype with Z-END Concentration in Patients with Breast Cancer Receiving Tamoxifen Therapy in Indonesian Population

2019 ◽  
Vol 19 (8) ◽  
pp. 1198-1206 ◽  
Author(s):  
Yenny ◽  
Sonar S. Panigoro ◽  
Denni J. Purwanto ◽  
Adi Hidayat ◽  
Melva Louisa ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Steady State ◽  
Ultra Performance Liquid Chromatography ◽  
Cross Sectional Study ◽  
Threshold Concentration ◽  
Breast Cancer Patients ◽  
Cross Sectional ◽  
Significant Difference ◽  
Pcr Rflp ◽  
Liquid Chromatography Tandem Mass

Background: Tamoxifen (TAM) is a frequently used hormonal prodrug for patients with breast cancer that needs to be activated by cytochrome P450 2D6 (CYP2D6) into Zusammen-endoxifen (Z-END). Objective: The purpose of the study was to determine the association between CYP2D6*10 (c.100C>T) genotype and attainment of the plasma steady-state Z-END minimal threshold concentration (MTC) in Indonesian women with breast cancer. Methods: A cross-sectional study was performed in 125 ambulatory patients with breast cancer consuming TAM at 20 mg/day for at least 4 months. The frequency distribution of CYP2D6*10 (c.100C>T) genotypes (C/C: wild type; C/T: heterozygous mutant; T/T: homozygous mutant) was detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), the results of which were subsequently confirmed by sequencing. The genotypes were categorized into plasma Z- END concentrations of <5.9 ng/mL and ≥5.9 ng/mL, which were measured using ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Results: Percentages of C/C, CT, and T/T genotypes were 22.4%, 29.6%, and 48.8%, respectively. Median (25-75%) Z-END concentrations in C/C, C/T, and T/T genotypes were 9.58 (0.7-6.0), 9.86 (0.7-26.6), and 3.76 (0.9-26.6) ng/mL, respectively. Statistical analysis showed a significant difference in median Z-END concentration between patients with T/T genotype and those with C/C or C/T genotypes (p<0.001). There was a significant association between CYP2D6*10 (c.100C>T) genotypes and attainment of plasma steady-state Z-END MTC (p<0.001). Conclusion: There was a significant association between CYP2D6*10 (c.100C>T) and attainment of plasma steady-state Z-END MTC in Indonesian breast cancer patients receiving TAM at a dose of 20 mg/day.

Tuning the Localized Surface Plasmon Resonance of Al-Al2O3 Nanosphere Towards NIR Region by Gold Coating

2020 ◽  
Vol 12 ◽  
Author(s):  
Jyoti Katyal ◽  
Shivani Gautam
Keyword(s):  
Electric Field ◽  
Field Distribution ◽  
Dielectric Layer ◽  
Electric Field Distribution ◽  
Active Material ◽  
Visible Region ◽  
Field Enhancement ◽  
Localized Surface Plasmon ◽  
Sers Substrate ◽  
Al Nanoparticles

Background: A relatively narrow LSPR peak and a strong inter band transition ranging around 800 nm makes Al strongly plasmonic active material. Usually, Al nanoparticles are preferred for UV-plasmonic as the SPR of small size Al nanoparticles locates in deep UV-UV region of the optical spectrum. This paper focused on tuning the LSPR of Al nanostructure towards infrared region by coating Au layer. The proposed structure has Au as outer layer which prevent the further oxidation of Al nanostructure. Methods: The Finite Difference Time Domain (FDTD) and Plasmon Hybridization Theory has been used to evaluated the LSPR and field enhancement of single and dimer Al-Al2O3-Au MDM nanostructure. Results: It is observed that the resonance mode show dependence on the thickness of Al2O3 layer and also on the composition of nanostructure. The Au layered MDM nanostructure shows two peak of equal intensities simultaneously in UV and visible region tuned to NIR region. The extinction spectra and electric field distribution profiles of dimer nanoparticles are compared with monomer to reveal the extent of coupling. The dimer configuration shows higher field enhancement ~107 at 1049 nm. By optimizing the thickness of dielectric layer the MDM nanostructure can be used over UV-visible-NIR region. Conclusion: The LSPR peak shows dependence on the thickness of dielectric layer and also on the composition of nanostructure. It has been observed that optimization of size and thickness of dielectric layer can provide two peaks of equal intensities in UV and Visible region which is advantageous for many applications. The electric field distribution profiles of dimer MDM nanostructure enhanced the field by ~107 in visible and NIR region shows its potential towards SERS substrate. The results of this study will provide valuable information for the optimization of LSPR of Al-Al2O3-Au MDM nanostructure to have high field enhancement.

High-speed isotachophoresis. Analytical aspects of the steady-state longitudinal temperature profiles

1979 ◽  
Vol 44 (3) ◽  
pp. 841-853 ◽  
Author(s):  
Zbyněk Ryšlavý ◽  
Petr Boček ◽  
Miroslav Deml ◽  
Jaroslav Janák
Keyword(s):  
Steady State ◽  
Temperature Distribution ◽  
Electric Field ◽  
Field Intensity ◽  
Electric Field Intensity ◽  
Minor Component ◽  
Physical Models ◽  
Temperature Profiles ◽  
Longitudinal Temperature ◽  
Continuous Character

The problem of the longitudinal temperature distribution was solved and the bearing of the temperature profiles on the qualitative characteristics of the zones and on the interpretation of the record of the separation obtained from a universal detector was considered. Two approximative physical models were applied to the solution: in the first model, the temperature dependences of the mobilities are taken into account, the continuous character of the electric field intensity at the boundary being neglected; in the other model, the continuous character of the electric field intensity is allowed for. From a comparison of the two models it follows that in practice, the variations of the mobilities with the temperature are the principal factor affecting the shape of the temperature profiles, the assumption of a discontinuous jump of the electric field intensity at the boundary being a good approximation to the reality. It was deduced theoretically and verified experimentally that the longitudinal profiles can appreciably affect the longitudinal variation of the effective mobilities in the zone, with an infavourable influence upon the qualitative interpretation of the record. Pronounced effects can appear during the analyses of the minor components, where in the corresponding short zone a temperature distribution occurs due to the influence of the temperatures of the neighbouring zones such that the temperature in the zone of interest in fact does not attain a constant value in axial direction. The minor component does not possess the steady-state mobility throughout the zone, which makes the identification of the zone rather difficult.

scholarly journals Optically Induced Field-Emission Source Based on Aligned Vertical Carbon Nanotube Arrays

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1810
Author(s):  
Mengjie Li ◽  
Qilong Wang ◽  
Ji Xu ◽  
Jian Zhang ◽  
Zhiyang Qi ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Electric Field ◽  
Field Emission ◽  
Field Enhancement ◽  
Absorption Efficiency ◽  
Photon Absorption ◽  
Nanotube Arrays ◽  
Carbon Nanotube Arrays ◽  
Induced Field ◽  
Optically Induced

Due to the high field enhancement factor and photon-absorption efficiency, carbon nanotubes (CNTs) have been widely used in optically induced field-emission as a cathode. Here, we report vertical carbon nanotube arrays (VCNTAs) that performed as high-density electron sources. A combination of high applied electric field and laser illumination made it possible to modulate the emission with laser pulses. When the bias electric field and laser power density increased, the emission process is sensitive to a power law of the laser intensity, which supports the emission mechanism of optically induced field emission followed by over-the-barrier emission. Furthermore, we determine a polarization dependence that exhibits a cosine behavior, which verifies the high possibility of optically induced field emission.

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