scholarly journals Maximum rate of change of the differential reflection phase shift with respect to the angle of incidence for light reflection at the surface of an absorbing medium

1989 ◽  
Vol 28 (7) ◽  
pp. 1365 ◽  
Author(s):  
R. M. A. Azzam ◽  
A. M. El-Saba
1986 ◽  
Vol 250 (1) ◽  
pp. F86-F91
Author(s):  
R. V. Pinnick ◽  
V. J. Savin

We measured glomerular ultrafiltration coefficient (Kf) of isolated superficial (S) and deep (D) glomeruli of normovolemic and volume-depleted rats. Filtration was induced in vitro, and Kf was calculated from the maximum rate of change in glomerular size. Basement membrane area (A) for each glomerulus was estimated from morphometric analyses, and glomerular capillary hydraulic conductivity (Lp) was calculated by the formula Lp = Kf/A. Kf of S and D glomeruli of normovolemic rats were 2.98 +/- 0.98 and 4.25 +/- 0.07 nl . min-1 . mmHg-1, respectively. In hypovolemic rats, Kf of S glomeruli fell by approximately 50% to 1.52 +/- 0.14 nl . min-1 . mmHg-1 (P less than 0.001), whereas Kf of D glomeruli remained unchanged at 4.28 +/- 0.10 nl . min-1 . mmHg-1. Lp, calculated using the peripheral capillary area, averaged 1.98 +/- 0.09 and 1.98 +/- 0.06 microliter . min-1 . mmHg-1 . cm-2 in S and D glomeruli of normovolemic rats and 1.89 +/- 0.11 microliter . min-1 . mmHg-1 . cm-2 in D glomeruli of hypovolemic rats. Lp of S glomeruli of volume-depleted rats (0.90 +/- 0.03 microliter . min-1 . mmHg-1 . cm-2) was lower than in any of the other three samples. Mild hypovolemia causes the Kf of S glomeruli to decline, whereas Kf of D glomeruli remains constant. The decrease in Kf occurs without an alteration in capillary area and is most likely due to a decrease in Lp.


Author(s):  
М.С. Воробьёв ◽  
П.В. Москвин ◽  
В.И. Шин ◽  
Н.Н. Коваль ◽  
К.Т. Ашурова ◽  
...  

The paper describes a method for a controlled change in the power of an electron beam during a pulse of submillisecond duration, using a source "SOLO" with a plasma cathode. The beam power is controlled by changing the amplitude of the beam current with a corresponding change in the concentration of the emission plasma. This control method allows generating submillisecond beams of variable power (up to 10 MW at a maximum rate of change of no more than 0.5 MW/µs), which can be used for processing various metallic materials in order to change the functional properties of their surface with the ability to control the rate of input of beam energy into the surface of these materials.


1965 ◽  
Vol 208 (4) ◽  
pp. 720-723 ◽  
Author(s):  
Gordon M. Schoepfle ◽  
Eliska Atkins ◽  
Larry A. Schafer

Under conditions of continuous fluid exchange at a pH 7.55, a 10-min exposure of Xenopus sciatic single nerve fibers to iodoacetate results in eventual decline in the maximum rate of change of membrane potential, even after a delay of an hour or more during which no changes are apparent. This delayed effect is obtained over an iodoacetate concentration range of 0.1–20.0 mm sodium iodoacetate. Neither the resting membrane potential nor the maximal limiting response obtained during hyperpolarization are affected at a time when iodoacetate has appreciably depressed the spike in the nonpolarized fiber. These findings are taken to indicate that iodoacetate blocks a chain of reactions at a link remote from the process directly concerned with maintenance of the resting level of the sodium conductance. Neither lactate nor pyruvate can be relied on to bring about recovery from the iodoacetate depression.


1977 ◽  
Vol 23 (8) ◽  
pp. 1456-1464 ◽  
Author(s):  
J C Sternberg

Abstract A kinetic nephelometric method and instrument have been developed for the rapid determination of specific serum proteins by means of immunoprecipitin reactions. The maximum rate of change of scattered light intensity in an antigen-antibody reaction can be made to occur within 60 s after initiation of the reaction and provides a measure of the antigen concentration under antibody excess conditions. A mathematical relationship has been found for the conversion of the nonlinear maximum rate data directly into a linear concentration read-out, making possible the use of single-point calibration. Instrument operating parameters and computations are programmed for a particular analysis by means of machine-readable cards. Antigen-excess samples are detected rapidly by injection of calibrator into the reaction mixture after the rate signal has dropped to a pre-selected level. The method correlates well with both radial immunodiffusion and end-point nephelometric methods.


1990 ◽  
Vol 112 (3) ◽  
pp. 331-334 ◽  
Author(s):  
J. Yang ◽  
S. L. Plee ◽  
D. J. Remboski ◽  
J. K. Martin

Measurements of the radiant emission in the near infrared have been obtained in a spark-ignition engine over a wide range of operating conditions. The system includes an in-cylinder optical sensor and associated detector. Prior work has shown correlations between the measured radiance and pressure quantities such as maximum cylinder pressure, crank angle of maximum pressure, and Indicated Mean Effective Pressure. Here are presented comparisons between the radiant intensity and a simplified model of the radiation emission, which demonstrate that the measured intensity is a function of the mass-burn fraction, mean burned-gas temperature, and the exposed combustion-chamber surface area. Further simplification leads to the conclusion that the time of the maximum rate of change of radiant intensity is the same as for the maximum heat-release rate, leading to the possibility of feedback control of spark timing. In addition, the magnitudes of the maximum rate of change of radiant emission and maximum heat-release rate have a linear relationship over a range of different operating conditions.


2020 ◽  
Vol 101 (4) ◽  
Author(s):  
Xingdong Luo ◽  
Cheng Hu ◽  
Bosai Lyu ◽  
Liu Yang ◽  
Xianliang Zhou ◽  
...  

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