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Showing papers by "Jet Propulsion Laboratory published in 1975"


Journal ArticleDOI
TL;DR: In this paper, the amplitude ratio of constant-frequency disturbances as a function of Reynolds number for insulated and cooled-wall flat-plate boundary layers between Mach numbers 1.3 and 5.8 is calculated.
Abstract: Compressible linear stability theory is first reviewed and then used to calculate the amplitude ratio of constant-frequency disturbances as a function of Reynolds number for insulated and cooled-wall flat-plate boundary layers between Mach numbers 1.3 and 5.8. These results are used to examine the consequences of using a fixed disturbance amplitude of the most unstable frequency as a transition criterion. The effect of the freestream Mach number M1 on the transition of insulated-wall boundary layers is calculated using two different assumptions concerning the initial boundary-layer disturbance amplitude A0. It is found that the shape of the transition Reynolds number Ret vs MI curve observed in wind tunnels can be closely duplicated. As a second example, the effect of wall cooling at MI = 3.0 is calculated. A much faster increase of Re, with cooling is obtained than is observed experimentally. However, when A0 is determined from the forced response of the boundary layer to irradiated sound and from the measured freestream power spectrum, a rise in Re, similar to what is observed is obtained for a certain amplitude criterion.

515 citations


Journal ArticleDOI
TL;DR: In this paper, hot-wire anemometry is used to study the origin and growth of "natural" fluctuations in zero pressure-gradient boundary layers for several Mach numbers between 1.6 and 8.5.
Abstract: Hot-wire anemometry is used to study the origin and growth of "natural" fluctuations in zero pressure-gradient boundary layers for several Mach numbers between 1.6 and 8.5. The importance to transition of certain physical mechanisms is examined through comparison of the fluctuation growth with the sound-forcing and stability theories of Mack. Flow fluctuations of substantial amplitude were observed within the laminar layer ahead of stations where instability amplification is expected to be important. These fluctuations were found to be cross-correlated with the sound field for the higher supersonic speeds, but not for the lower ones. The fluctuation growth rates in the unstable Reynolds number range ahead of the nonlinearity region were in reasonably close agreement with the theory for Mach 4.5; the agreement for Mach 2.2 and 8.5 was qualitative. The second mode of instability was predominant at Mach 8.5.

391 citations


Patent
10 Feb 1975
TL;DR: In this article, a process and apparatus for producing a hydrogen rich gas by injecting air and hydrocarbon fuel at one end of a cylindrically shaped chamber to form a mixture, igniting the mixture to provide hot combustion gases, by partial oxidation of the hydrocar fuel.
Abstract: A process and apparatus is described for producing a hydrogen rich gas by injecting air and hydrocarbon fuel at one end of a cylindrically shaped chamber to form a mixture, igniting the mixture to provide hot combustion gases, by partial oxidation of the hydrocarbon fuel. The combustion gases move away from the ignition region to another region where water is injected to be turned into steam by the hot combustion gases. The steam which is formed mixes with the hot gases present to yield a uniform hot gas whereby a steam reforming reaction with the hydrocarbon fuel takes place to produce a hydrogen rich gas.

148 citations


Journal ArticleDOI
02 May 1975-Science
TL;DR: The Pioneer 11 vector helium magnetometer provided precise, contititious measurements of the magnetic fields in interplanetary space, inside Jupiter's magnetosphere, and in the near vicinity of Jupiter.
Abstract: Measurements of the magnetic field vector were obtained continuously throughout the encounter of the spacecraft with the planet Jupiter. Effects of Jupiter on the solar wind are considered along with the characteristics of the magnetopause at both low and intermediate latitudes, the three basic regions within the magnetosphere, and a spherical harmonic analysis of the Pioneer 11 measurements. The spherical harmonic representation has been used to derive contours of the magnetic field strength at the surface of Jupiter.

137 citations


Journal ArticleDOI
TL;DR: This paper compares two possible quadrature amplitudes-shift-keyed (QASK) signal sets when the number of bits per symbol is odd and finds the "symmetric" QASK version outperforms the "rectangular" Q ASK set at a very modest implmentation penalty.
Abstract: The selection of a particular signal set design for a bandwidth-constrained multiple amplitude-and-phase-amplitude-and-phase-shift-keyed (MAPSK) communication system with a linear additive Gaussian noise channel is influenced by a number of factors, such as average and/or peak signal-to-noise ratio for a given error probability, dynamic range of signal amplitudes, simplicity of generation and detection, and number of bit errors per adjacent symbol error (Gray code properties). This paper compares two possible quadrature amplitudes-shift-keyed (QASK) signal sets when the number of bits per symbol is odd (for the even-bit case, the square array is the only viable QASK choice). The "symmetric" QASK version outperforms the "rectangular" QASK set at a very modest implmentation penalty.

112 citations


Journal ArticleDOI
TL;DR: It is concluded that graphite Fiber reinforcement is beneficial in improving certain mechanical and thermal properties of surgical bone cement, however, considerable effort remains to produce a clinically usable graphite fiber reinforced bone cement.
Abstract: This paper presents the results of a brief experimental investigation to determine the effects of graphite fiber additives on the flexuaral, compressive, and exothermal characteristics of surgical bone cement. The materials used in the investigation were polymethyl-methacrylate (PMM) and chopped graphite (GY70) fibers. Both fiber reinforced and unrein-forced beam and cylinder specimens were fabricated and tested. The unreinforced specimens were used to develop baseline data.

63 citations


Journal ArticleDOI
TL;DR: In this article, the Galerkin finite element method is applied to a two-dimensional structure with a tensor conductivity, and a model consisting of an anisotropic, conducting dike embedded in a half-space is presented.
Abstract: The lack of agreement between magnetotelluric field measurements and the calculations based on essentially two‐dimensional models with either anisotropy or lateral inhomogeneity necessitates a more complex model of the earth than has been previously considered. The Galerkin finite‐element method is applied to a two‐dimensional structure with a tensor conductivity. The importance of considering conductivity as a tensor is illustrated by a model consisting of an anisotropic, conducting dike embedded in an anisotropic half‐space. This model can be distinguished from an isotropic model by the nonvanishing diagonal elements of the impedance tensor, the ellipticity indices, and the skew.

58 citations


Patent
23 Jun 1975
TL;DR: In this paper, a space communication system incorporating a concatenated Reed Solomon Viterbi coding channel is disclosed for transmitting compressed and uncompressed data from a spacecraft to a data processing center on Earth.
Abstract: A space communication system incorporating a concatenated Reed Solomon Viterbi coding channel is disclosed for transmitting compressed and uncompressed data from a spacecraft to a data processing center on Earth. Imaging (and other) data is first compressed into source blocks which are then coded by a Reed Solomon coder and interleaver with parameters J=8, E=16, I=16, followed by a convolutional encoder of parameters k=7, ν=2. The received data is first decoded by a Viterbi decoder, followed by a Reed Solomon decoder and deinterleaver. The output of the latter is then decompressed, based on the compression criteria used in compressing the data in the spacecraft. The decompressed data is processed to reconstruct an approximation of the original data-producing condition or images.

57 citations


Journal ArticleDOI
TL;DR: In this paper, the authors considered the problem of curtailing the vapid growth of cancer cell populations and devised a performance functional that measures the size of the population at the terminal time as well as the control effort.
Abstract: This study deals with ways of curtailing the vapid growth of cancer cell populations. The performance functional that measures the size of the population at the terminal time as well as the control effort is devised. With use of the discrete maximum principle, the Hamiltonian for this problem is determined and the condition for optimal solutions are developed. The optimal strategy is shown to be a bang-bang control. It is shown that the optimal control for this problem must be on the vertices of an N -dimensional cube contained in the N -dimensional Euclidean space. An algorithm for obtaining a local minimum of the performance function in an orderly fashion is developed. Application of the algorithm to the design of antitumor drug and X -irradiation schedule is discussed.

57 citations


Patent
24 Sep 1975
TL;DR: In this paper, an inexpensive, lightweight reflective assembly member having good optical quality is provided, which is particularly adaptable to accommodating temperature variations without providing destructive thermal stresses and reflective slope errors.
Abstract: An inexpensive, lightweight reflective assembly member having good optical quality is provided. The reflective assembly is particularly adaptable to accommodating temperature variations without providing destructive thermal stresses and reflective slope errors. The reflective assembly may consist of a thin lamina reflective surface member and a lightweight substrate member of cellular structure. The respective materials may be chosen so that the coefficient of thermal expansion will be approximately the same. The substrate can comprise a cellular glass block while the reflective lamina member can be a thin sheet of glass with appropriate reflective coating. The lamina and cellular substrate member can be bonded together to form the reflective assembly. The method of fabrication includes abrading the cellular substrate with an abrasive master die to form an appropriate concave surface. An adhesive can be applied to the abraded surface and a lamina reflective surface can be placed under a uniform pressure to conform the reflective surface onto the desired abraded surface of the substrate.

50 citations


Journal ArticleDOI
TL;DR: This comprehensive study into the irreversible oxidation and reduction properties of the triplet state of zinc uroporphyrin (ZnUP) found the similarities in the redox and spectral properties between ZnUP and chlorophyll excited states rendered this study relevant.
Abstract: The necessity of unraveling the complex reactions of photosynthesis inspired this comprehensive study into the irreversible oxidation and reduction properties of the triplet state of zinc uroporphyrin (ZnUP). The similarities in the redox and spectral properties between ZnUP and chlorophyll excited states rendered this study relevant. In addition, the eight ionized acetic and propionic acid groups on the periphery of the uroporphyrin molecule permitted the determination of a distance of electron transfer from the triplet state t o various acceptors. The importance of these findings t o porphyrin photochemistry and photosynthesis will be presented in this report. The absorption spectra and decay kinetics of some free base and metalloporphyrin triplet states have been That the ground state of metalloporphyrins undergo successive one-electron aromatic ring oxidations6-'0 and reductions1 '-' is well documented. Similarly, one-electron electrochemical oxidations of tetraphenylporphin,' and successive one-electron electrochemical reductions of various free-base porphyrins have been reported.' 6 i 1 Photochemical reductions of uroporphyrin' 8 -2 and zinc porphin2 have been demonstrated, although the reactive state was not conclusively identified. The one-electron reduction of ground state zinc etioporphyrinZ3 and the one-electron oxidations of the triplet state of zinc t e t r a p h e n y l p ~ r p h y r i n ~ ~ by chemical means have also been reported. PhotoreductionSv2 5 , 2 6 and p h o t o ~ x i d a t i o n ~ > ~ 6 9 2 7 of chlorophyll and chlorophyll-related2 8 30 compounds have also been studied, and reaction from the triplet state was demonstrated in several cases.26-28g30 A quantitative mechanistic study, however, has not been reported and will be presented for triplet state ZnUP in this report.

Journal ArticleDOI
TL;DR: In this article, the authors describe two relatively simple reductions to order 6 for the planar general three-body problem, and show that this reduction leads to the distinction between two types of periodic solutions: absolute or relative periodic solutions.
Abstract: We describe two relatively simple reductions to order 6 for the planar general three-body problem. We also show that this reduction leads to the distinction between two types of periodic solutions: absolute or relative periodic solutions. An algorithm for obtaining relative periodic solutions using heliocentric coordinates is then described. It is concluded from the periodicity conditions that relative periodic solutions must form families with a single parameter. Finally, two such families have been obtained numerically and are described in some detail.

Journal ArticleDOI
01 Aug 1975
TL;DR: The surface of Mare Imbrium contains some of the most distinct red-blue colorimetric boundaries and depolarized 70-cm wavelength-reflectivity variations on the near side of the moon as mentioned in this paper.
Abstract: The surface of Mare Imbrium contains some of the most distinct red-blue colorimetric boundaries and depolarized 70-cm wavelength-reflectivity variations on the near side of the moon. The weakest levels of both 3.8-cm and 70-cm reflectivity within Imbrium are confined to spectrally blue regional mare surfaces that can be recognized as stratigraphically unique flow surfaces. Frequency distributions of the 70-cm polarized and depolarized radar-return power for five mare surfaces within the basin indicate that signal absorption, and probably ilmenite content, increases generally from the beginning of the Imbrium Period to the end of the Eratosthenian Period with slight reversal between the end of the Imbrium and beginning of the Eratosthenian. TiO2 calibrated radar-reflectivity curves can be utilized for lunar-maria geochemical mapping in the same manner as the TiO2 calibrated spectral-reflectivity curves of Charette et al. (1974).

Patent
16 May 1975
TL;DR: A force transducer for measuring dynamic force activity within the heart of a subject essentially consists of a U-shaped beam of low elastic compliance material, two tines extend from the beam's legs and a long coil spring is attached to the beam as discussed by the authors.
Abstract: A force transducer for measuring dynamic force activity within the heart of a subject essentially consists of a U-shaped beam of low elastic compliance material. Two tines extend from the beam's legs and a long coil spring is attached to the beam. A strain gauge is coupled to one of the beam's legs to sense deflections thereof. The beam with the tines and most of the spring are surrounded by a flexible tube, defining a catheter, which is insertable into a subject's heart through an appropriate artery. The tines are extractable from the catheter for implantation into the myocardium by pushing on the end of the spring which extends beyond the external end of the catheter. The tines are retractable back into the catheter, prior to catheter removal from the subject, by pulling on the externally exposed spring end.

Patent
18 Dec 1975
TL;DR: In this paper, three detectors at the output of the interferometer are disposed on mutually perpendicular axes which define a plane normal to the nominal exit beam axis, one detector at the origin of the axes is used as a reference for separate phase-difference comparison with the outputs of the other two detectors on the X and Y axes to develop servo error signals.
Abstract: An interferometer having servo means for automatically adjusting the angular tilt of a reflecting surface in one of two paths to maintain the exit beams from the two paths parallel to each other. Three detectors at the output of the interferometer are disposed on mutually perpendicular axes which define a plane normal to the nominal exit beam axis. One detector at the origin of the axes is used as a reference for separate phase-difference comparison with the outputs of the other two detectors on the X and Y axes to develop servo error signals.

Patent
23 Jun 1975
TL;DR: In this paper, a charge-coupled device (CCD) was used to perform input sampling, presumming, range correlation and azimuth correlation in the analog domain.
Abstract: Processing of raw analog echo data from a side-looking synthetic aperture radar receiver into images on board an airborne radar platform is made feasible by utilizing charge-coupled device (CCD) semiconductor technology. CCD circuits are utilized to perform input sampling, presumming, range correlation and azimuth correlation in the analog domain. These radar data processing functions are implemented for "single-look" or "multiple-look" imaging radar systems.

Journal ArticleDOI
TL;DR: In this article, the Dyer-McReynolds square-root information filter (SRIF) is re-derived, using recursive least-square arguments, and applied to a system composed partly of biases.
Abstract: The Dyer-McReynolds square-root information filter (SRIF) is rederived, using recursive least-square arguments. The result is applied to a system composed partly of biases. The filter sensitivity matrix, computed covariance, and consider covariance for this augmented system are reviewed. A new computationally attractive representation for the smoothed estimates, in terms of a smoothed sensitivity matrix and a smoothed computed covariance is presented.

Journal ArticleDOI
TL;DR: In this article, a rational criterion for structural dynamic analysis-test correlation has been established by using a matrix perturbation technique, which can be used for the verification of an analytical model by the test results.
Abstract: A rational criterion for structural dynamic analysis-test correlation has been established by using a matrix perturbation technique. This criterion can be used for the verification of an analytical model by the test results. Also, the same technique can be applied to update the analytical results by using the test results without repeating the entire analytical procedure. A sample problem has been used to demonstrate this technique. Very satisfactory results are obtained with only the first-order perturbation solution included for transient loading. For periodic loading, higher-order perturbation solutions are needed to achieve the same accuracy.

Journal ArticleDOI
TL;DR: In this article, a numerical study of periodic solutions of the Planar General Three-Body Problem with variable masses has been presented, extending all the way from the elliptic restricted problem to the general problem with three equal masses.
Abstract: The article contains a numerical study of periodic solutions of the Planar General Three-Body Problem. Several new periodic solutions have been discovered and are described. In particular, there is a continuous family with variable masses, extending all the way from the elliptic restricted problem to the general problem with three equal masses. All our examples have special symmetry properties which are described in detail. Finally we also suggest some important applications to the natural satellites of the solar system.

Patent
20 Nov 1975
TL;DR: Cermet compositions have been designed particularly to provide high temperature resistant refractory coatings on stainless steel or molybdenum substrates as discussed by the authors, and have high temperature oxidation resistance, high abrasion and corrosion resistances and good thermal shock resistance.
Abstract: Cermet composition having high temperature oxidation resistance, high abrasion and corrosion resistances, and good thermal shock resistance, and particularly adapted for production of high temperature resistant cermet insulator bodies, comprising a sintered body of particles of stainless steel or molybdenum, in a ceramic phase comprised of a ceramic oxide, particularly a ceramic mixture of chromium oxide and aluminum oxide, and forming a coating of chromium oxide as an oxidation barrier around the metal particles, to provide oxidation resistance for the metal particles. The cermet compositions are designed particularly to provide high temperature resistant refractory coatings on stainless steel or molybdenum substrates.

Journal ArticleDOI
TL;DR: In this paper, the authors determined the positions of the two Martian satellites Phobos and Deimos from 80 television photographs of the satellites taken by the imaging system of the Mariner 9 spacecraft.
Abstract: Orbit elements for the two Martian satellites Phobos and Deimos have been determined from 80 television photographs of the satellites taken by the imaging system of the Mariner 9 spacecraft. Phobos was found to be within 60 km of its positions predicted by recently published ephemeris theories which include a secular acceleration term in the longitude. This tends to corroborate the existence of a secular acceleration in the longitude of Phobos. Deimos was found to be within 100 km of its position predicted from Earth-based observations.

Journal ArticleDOI
TL;DR: In this paper, the optimal trajectories in the neighborhood of an optimal intermediate-thrust arc are investigated for the minimum-fuel orbit rendezvous problem with fixed specific impulse, where a second-variation analysis leads to the identification of a field of neighboring singular arcs in a state space of dimension four rather than six, provided that a suitable Jacobi condition is met.
Abstract: The optimal trajectories in the neighborhood of an optimal intermediate-thrust arc are investigated for the minimum-fuel orbit rendezvous problem with fixed specific impulse. Since such an arc is singular, the thrust acceleration magnitude being the singular control component, a second-variation analysis leads to the identification of a field of neighboring, singular arcs in a state space of dimension four rather than six, provided that a suitable Jacobi condition is met. A given neighboring initial six-dimensional state vector does not generally lie on a neighboring singular arc, and junction onto the appropriate singular arc must be accomplished by a short period of strong variations in the acceleration. The neighboring singular arc meets the final condition in 4 dimensions, rather than 6 dimensions, and rendezvous must be completed by another, terminal short period of strong variations in the acceleration. Implications for midcourse guidance near a singular arc are discussed.

Patent
24 Sep 1975
TL;DR: In this article, a sun direction detection system is disclosed, consisting of two spaced apart elongated strips with a strip of cadmium sulphide (CdS) deposited there between.
Abstract: A sun direction detection system is disclosed. It includes a housing with a slit, through which a line image of the sun is directed into the housing in a first direction. Placed in the housing is a substrate on which at least one pair of detectors are deposited in a direction perpendicular to the first direction. One of the detectors is an illumination detector consisting of two spaced apart elongated strips with a strip of cadmium sulphide (CdS) deposited therebetween. Whenever the line image impinges the CdS strip, the resistance between the two other strips is relatively low, while being high when the line image is outside the field of view of the illumination detector. Also included is a sun angle detector which consists of a vapor deposited resistor strip connected at one end to +10v and at the other end to -10v. Spaced apart from the resistor strip is an elongated strip of low resistance material acting as an output strip, with a CdS strip between the two strips. When the line image is within the field of view of the sun angle detector, the output voltage at the output strip depends on the position of the line image across the sun angle detector. When the line image is at one end, the output voltage is +10v and when the line image is at the other end, the output voltage is -10v. The field of view of the illumination detector is less than that of the sun angle detector so that the change of resistance of the illumination detector from high to low or low to high occurs when the output voltage is either +10v or -10v, depending on the position of the line image with respect to the two detectors.

Patent
25 Jul 1975
TL;DR: In this paper, the sensitivity of an opto-acoustic absorption detector is increased to make it possible to measure trace amounts of constituent gases (approaching 0.01 parts per billion) in a sample by creating a second beam radiation path through the sample cell identical to a first path except as to length, alternating the beam through two paths and minimizing the detected pressure difference for the two paths while the beam wavelength is tuned away from the absorption lines of the sample.
Abstract: The sensitivity of an opto-acoustic absorption detector is increased to make it possible to measure trace amounts of constituent gases (approaching 0.01 parts per billion) in a sample by creating a second beam radiation path through the sample cell identical to a first path except as to length, alternating the beam through the two paths and minimizing the detected pressure difference for the two paths while the beam wavelength is tuned away from the absorption lines of the sample. Then with the beam wavelength tuned to the absorption line of any constituent of interest, the pressure difference is a measure of trace amounts of the constituent. The same improved detector may also be used for measuring the absorption coefficient of known concentrations of absorbing gases.

Patent
24 Jul 1975
TL;DR: In this paper, a fixed, linear, ground-based primary reflector having an extended curved-sawtooth contoured surface covered with a metallized polymeric reflecting material, reflects solar energy to a movably supported collector that is kept at the concentrated line focus of the reflector primary.
Abstract: A fixed, linear, ground-based primary reflector having an extended curved-sawtooth contoured surface covered with a metallized polymeric reflecting material, reflects solar energy to a movably supported collector that is kept at the concentrated line focus of the reflector primary. The primary reflector may be constructed by a process utilizing well-known freeway paving machinery. The solar energy absorber is preferably a fluid-transporting pipe. Efficient utilization leading to high temperatures from the reflected solar energy is obtained by cylindrical shaped secondary reflectors that direct off-angle energy to the absorber pipe. To obtain higher temperature levels, refocusing secondary reflectors, that cause a series of discrete spots of highly concentrated solar energy to fall on the fluid-transporting pipe, are utilized. A seriatim arrangement of cylindrical secondary reflector stages and spot-forming reflector stages produces a high temperature solar energy collection system of greater efficiency.

Journal ArticleDOI
TL;DR: This article corrects the article on p. 787 in vol.
Abstract: The ability to determine the thermal resistance of naturally occurring air borne bacterial spores associated with spacecraft and their assembly areas has been hindered by lack of an effective collecting system. Efforts to collect and concentrate spores with air samplers or from air filters have not been successful. A fallout method was developed for this purpose and tested. Sterile Teflon ribbons (7.6 by 183 cm) were exposed in pertinent spacecraft assembly areas and subsequently treated with dry heat. Thermal inactivation experiments were conducted at 125 and 113 C. Heating intervals ranged from 1 to 12 h at 125 C and 6, 12, 18, and 24 h at 113 C. Eight hours was the longest heating time yielding survivors at 125 C, whereas survivors were recovered at all of the heating intervals at 113 C. D125C values were calculated using the fractional-replicate-unit-negative technique of Pflug and Schmidt (1968) and ranged from 25 to 126 min. This variation indicated that the most probable number of survivors at each heating interval did not fall on a straight line passing through the initial spore population. However, the most-probable-number values taken alone formed a straight line suggesting logarithmic thermal destruction of a subpopulation of spores with a D125C value of 6.3 h.

Patent
05 May 1975
TL;DR: In this article, a Stirling cycle heat engine is described in which displacer motion is controlled as a function of the working fluid pressure P 1 and a substantially constant pressure P 0.
Abstract: A Stirling cycle heat engine is disclosed in which displacer motion is controlled as a function of the working fluid pressure P 1 and a substantially constant pressure P 0 . The heat engine includes an auxiliary chamber at the constant pressure P 0 . An end surface of a displacer piston is disposed in the auxiliary chamber. During the compression portion of the engine cycle when P 1 rises above P 0 the displacer forces the working fluid to pass from the cold chamber to the hot chamber of the engine. During the expansion portion of the engine cycle the heated working fluid in the hot chamber does work by pushing down on the engine's drive piston. As the working fluid pressure P 1 drops below P 0 the displacer forces most of the working fluid in the hot chamber to pass through the regenerator to the cold chamber. The engine is easily combinable with a refrigeration section to provide a refrigeration system in which the engine's single drive piston serves both the engine and the refrigeration section.

Patent
05 May 1975
TL;DR: In this article, a high-resolution Fourier interferometer-spectrophotopolarimeter is provided using a single linear polarizer-analyzer the transmission axis azimuth of which is positioned successively in the three orientations of 0°, 45°, and 90°, in front of a detector.
Abstract: A high-resolution Fourier interferometer-spectrophotopolarimeter is provided using (i) a single linear polarizer-analyzer the transmission axis azimuth of which is positioned successively in the three orientations of 0°, 45°, and 90°, in front of a detector; (ii) four flat mirrors, three of which are switchable to either of two positions to direct an incoming beam from an interferometer to the polarizer-analyzer (1) around a sample cell (2) transmitted through a medium in a cell and (3) reflected by medium in the cell; and (iii) four fixed focussing lenses, all located in a sample chamber attached at the exit side of the interferometer. This arrangement can provide the distribution of energy and complete polarization state across the spectrum of (a) the reference light entering from the interferometer; (b) the same light after a fixed-angle reflection from the sample cell containing a medium to be analyzed; and (c) the same light after direct transmission through the same sample cell, with the spectral resolution provided by the interferometer.

Journal ArticleDOI
TL;DR: An attempt is made to relate the prolongation of cell mean generation time with processes of cell death and dead cell clearance and it becomes apparent that in fact transition of proliferating cells to the resting states occurs somewhere close to the end of the cell cycle and with a rate that varies with the age of the tumor.

Journal ArticleDOI
TL;DR: In this paper, the line strengths of water vapor and nitrous oxide in the 1900 cm−1 region have been measured with moderate spectral resolution (∼0.15 cm −1).