The Analysis of Photoelectric Sensitivity Curves for Clean Metals at Various Temperatures

1931 ◽  
Vol 38 (1) ◽  
pp. 45-56 ◽  
Author(s):  
R. H. Fowler
Keyword(s):  
Sensitivity Curves ◽  
Photoelectric Sensitivity

Development of a method for multielemental determination in water by EDXRF with radioisotopic source of 238Pu.

2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
Camilo Fuentes Serrano ◽  
Juan Reinaldo Estevez Alvares ◽  
Alfredo Montero Alvarez ◽  
Ivan Pupo Gonzales ◽  
Zahily Herrero Fernandez ◽  
...  
Keyword(s):  
Thin Layer ◽  
Expanded Uncertainty ◽  
Considerable Decrease ◽  
X Ray ◽  
Precipitation Efficiency ◽  
Method Of Determination ◽  
Sensitivity Curves ◽  
Order Of Magnitude ◽  
Metrological Parameters

A method for determination of Cr, Fe, Co, Ni, Cu, Zn, Hg and Pb in waters by Energy Dispersive X Ray Fluorescence (EDXRF) was implemented, using a radioisotopic source of 238Pu. For previous concentration was employed a procedure including a coprecipitation step with ammonium pyrrolidinedithiocarbamate (APDC) as quelant agent, the separation of the phases by filtration, the measurement of filter by EDXRF and quantification by a thin layer absolute method. Sensitivity curves for K and L lines were obtained respectively. The sensitivity for most elements was greater by an order of magnitude in the case of measurement with a source of 238Pu instead of 109Cd, which means a considerable decrease in measurement times. The influence of the concentration in the precipitation efficiency was evaluated for each element. In all cases the recoveries are close to 100%, for this reason it can be affirmed that the method of determination of the studied elements is quantitative. Metrological parameters of the method such as trueness, precision, detection limit and uncertainty were calculated. A procedure to calculate the uncertainty of the method was elaborated; the most significant source of uncertainty for the thin layer EDXRF method is associated with the determination of instrumental sensitivities. The error associated with the determination, expressed as expanded uncertainty (in %), varied from 15.4% for low element concentrations (2.5-5 μg/L) to 5.4% for the higher concentration range (20-25 μg/L).

Micro Parameters Sensitivity of Coarse Grained Material in Mechanics and Deformation Based on PFC3D

2016 ◽  
Vol 873 ◽  
pp. 115-119
Author(s):  
Zhi Hua Zhang ◽  
Xie Dong Zhang ◽  
Hong Sheng Qiu ◽  
Bei Yang Zhang
Keyword(s):  
Weighted Average ◽  
Shear Stiffness ◽  
Coarse Grained ◽  
Triaxial Tests ◽  
Deformation Analysis ◽  
Analysis Method ◽  
Particle Rotation ◽  
Sensitivity Curves ◽  
Coarse Grained Material ◽  
Strength And Deformation

In order to study the effects of various parameters on macro-mechanical and deformational characteristics of coarse grained material based on discrete element method, triaxial tests have been conducted. Weighted average assembling method is used to assemble the numerical model based on PFC3D. The ratio of normal and shear stiffness of particles (kn/ks), shearing rate and friction coefficient are chosen as micro parameters to analyze the influential sensitivity. Curves of stress-strain intensity are taken as the mechanical analytic method. The particle rotation field as deformation analysis method is proposed to sort the sensitivity of these parameters in strength and deformation of coarse grained material. The research shows that the parameters have a certain effect on the strength and deformation of coarse grained material. kn/ks has the greatest influence on both. The sensitive list of the strength and deformation hopefully can be discussed with the relevant scholars, which can provide a reference for the adjustment of micro parameters in numerical field.

scholarly journals MEMS-Based Integrated Triaxial Electrochemical Seismometer

Micromachines ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1156
Author(s):  
Wenjie Qi ◽  
Bowen Liu ◽  
Tian Liang ◽  
Jian Chen ◽  
Deyong Chen ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Ground Motion ◽  
Small Volume ◽  
Three Dimensional ◽  
Experimental Results ◽  
Good Prospect ◽  
High Symmetry ◽  
Noise Levels ◽  
Sensitivity Curves ◽  
Simulation Results

This paper presents a micro-electromechanical systems (MEMS)-based integrated triaxial electrochemical seismometer, which can detect three-dimensional vibration. By integrating three axes, the integrated triaxial electrochemical seismometer is characterized by small volume and high symmetry. The numerical simulation results inferred that the integrated triaxial electrochemical seismometer had excellent independence among three axes. Based on the experimental results, the integrated triaxial electrochemical seismometer had the advantage of small axial crosstalk and could detect vibration in arbitrary directions. Furthermore, compared with the uniaxial electrochemical seismometer, the integrated triaxial electrochemical seismometer had similar sensitivity curves ranging from 0.01 to 100 Hz. In terms of random ground motion response, high consistencies between the developed integrated triaxial electrochemical seismometer and the uniaxial electrochemical seismometer could be easily observed, which indicated that the developed integrated triaxial electrochemical seismometer produced comparable noise levels to those of the uniaxial electrochemical seismometer. These results validated the performance of the integrated triaxial electrochemical seismometer, which has a good prospect in the field of deep geophysical exploration and submarine seismic monitoring.

Parameter Sensitivity Analysis of Piezoelectrically-Actuated Flexural/Torsional Vibrating Beams

2020 ◽  
Author(s):  
Roya Salehzadeh ◽  
Nicholas Candelino ◽  
Mohammad Javad Khodaei ◽  
Amin Mehrvarz ◽  
Nader Jalili
Keyword(s):  
Sensitivity Analysis ◽  
Equations Of Motion ◽  
Parameter Sensitivity ◽  
Point Mass ◽  
Parameter Sensitivity Analysis ◽  
Piezoelectric Patch ◽  
Frequency Domain Methods ◽  
Sensitivity Curves ◽  
Vibrating Beams ◽  
Bending Modes

Abstract A numerical parameter sensitivity analysis is performed on the bending and torsional vibrations of a flexural-torsional vibrating beam gyroscope model. The gyroscope analyzed in this work is comprised of a rotating cantilever beam with a point-mass attached to its free end and a piezoelectric actuator fixed to a portion of its length. The governing equations of motion are derived using extended Hamilton’s principle and the steady-state magnitude response of the system is obtained through frequency domain methods. A sensitivity analysis is then carried out for the parameters including rotational speed of the base, the length of the beam, the location of the piezoelectric patch, and the location of the added point mass along the beam’s length. It is observed that, in the region surrounding specific configurations, small variations in the rotation rate, beam length and the location of the piezoelectric patch will result in significant changes to the amplitudes of the coupled vibrations and produce peaks in the sensitivity curves. Further, the amplitude of vibration tends to increase as the location of the added point-mass is moved closer to the free end. Generally, the bending modes are more sensitive to all of these parameter variations than are the torsional modes.

Die Spektralsensitivität von Insekten-Komplexaugen im Ultraviolett bis 290 mμ

1959 ◽  
Vol 14 (4) ◽  
pp. 273-278 ◽  
Author(s):  
Jost Bernhard Walther ◽  
Eberhard Dodt
Keyword(s):  
Ultraviolet Light ◽  
Periplaneta Americana ◽  
Light Adaptation ◽  
Compound Eye ◽  
Monochromatic Light ◽  
High Sensitivity ◽  
Relative Sensitivity ◽  
Calliphora Erythrocephala ◽  
Sensitivity Curves ◽  
Fly Eye

Behaviour experiments have shown that insects react to ultraviolet light. Almost no data are available within this spectral range, however, on the sensitivity of their light sense organs.In this investigation the relative spectral sensitivity (1/Q) of the compound eye of the fly, Calliphora erythrocephala, and various areas of the compound eye of the cockroach, Periplaneta americana, was measured including the ultraviolet range down to 290 mμ. Equal amplitudes of the electroretinogram indicated equal efficiencies of the stimuli.The sensitivity curve in both species shows, besides the known maximum in the blue green, a second maximum in the ultraviolet. This second maximum was found between 341-369 mμ depending on the species and the particular area of the eye. At still shorter wave lengths sensitivity decreases. In the fly eye and the upper part of the cockroach eye the sensitivity maximum in the ultraviolet is higher than in the bluegreen, whereas in the ventral part of the cockroch eye it is lower. Monochromatic light adaptation selectively influences the relative sensitivity of the upper part of the cockroach eye.The sensitivity curves are discussed with regard to visual pigments and types of receptors. Fluorescence of the eye media is considered to have only negligible if any influence on the high sensitivity for ultraviolet light.

scholarly journals Effect of Pyrisoxazole on Colletotrichum scovillei Infection and Anthracnose on Chili

Plant Disease ◽  
2020 ◽  
Vol 104 (2) ◽  
pp. 551-559
Author(s):  
Y. Y. Gao ◽  
X. X. Li ◽  
L. F. He ◽  
B. X. Li ◽  
W. Mu ◽  
...  
Keyword(s):  
Inhibitory Activity ◽  
Infection Process ◽  
Appressorium Formation ◽  
Baseline Sensitivity ◽  
Sensitivity Curves ◽  
Half Maximal Effective Concentration ◽  
Colletotrichum Scovillei ◽  
Feasible Alternative

Anthracnose caused by Colletotrichum scovillei is one of the most destructive diseases affecting chili production. Disease control mainly relies on conventional fungicides, and repeated exposure to single-site mode-of-action fungicides may pose a risk for the development of resistant isolates within the population. Our previous study suggested that pyrisoxazole has strong inhibitory activity against C. scovillei in vitro. However, the effects of pyrisoxazole on the C. scovillei infection process and the performance of pyrisoxazole in the field remain unclear. In this study, pyrisoxazole exhibited strong inhibitory activity against the mycelial growth, appressorium formation, and appressorium diameter of C. scovillei, with half maximal effective concentration values of 0.1986, 0.0147, and 0.0269 μg/ml, respectively, but had no effect on sporulation, even at the highest concentration of 1.6 μg/ml. The baseline sensitivity curves were unimodal with a long right-hand tail. The in vivo data showed that pyrisoxazole provided both preventive and curative activity against anthracnose on chili. Pyrisoxazole decreased the incidence of anthracnose and reduced disease progress. The results of electron microscopy showed that pyrisoxazole can affect the C. scovillei infection process by altering mycelial morphology, degrading conidia and germ tubes, suppressing conidial germination and appressorium formation, and enhancing conidiophore production. Pyrisoxazole can be used to effectively control anthracnose under field conditions and increase chili yield; moreover, no phytotoxicity symptoms were observed after treatment. These results provide new insight into the mechanisms by which pyrisoxazole controls disease and suggest that pyrisoxazole is a feasible alternative for the management of anthracnose in chili.

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