Showing papers by "Philips published in 1972"

Compounds and pseudo-binary alloys with the CuAl2(C16)-type structure I. Preparation and X-ray results

Abstract: A total of 46 binary compounds with the CuAl2(C16)-type structure have been prepared and their crystallographic properties (unit cell dimensions a and c and the atomic coordinate x) have been measured. Two new examples FeZr2 and GaTh2 are included. The existence of four compounds claimed to exist in this structure-type, viz., AlZr2, AlHf2, BCr2 and RuSn2, could not be confirmed. Moreover, data are presented for 11 pseudo-binary alloy systems showing complete solid-solution series, and for 12 other systems with limited regions of the CuAl2-type structure. The results show that c a is markedly dependent on the valence electron concentration, while the x-parameter more or less follows the oscillations in the c a- ratio .

Phase relations and hydrogen absorption in the lanthanum-nickel system

Abstract: The LaNi system has been reinvestigated in the range 50–100 at. % Ni. The following compounds were observed: LaNi, LaNi 1.4 , LaNi 2 , LaNi 3 , La 2 Ni 7 and LaNi 5 . For these compounds the lattice constants have been determined. The phase LaNi 5 has a relatively large homogeneity region at elevated temperatures. For the compounds LaNi x within this region the equilibrium hydrogen pressure, p , of the 40 °C isotherms was found to change from 2.75 atm for LaNi 4.9 to about 9.2 atm for LaNi 5.4 according to In p = Cx + q with C = 2.4, q = − 10.75.

Integrated injection logic: a new approach to LSI

Abstract: Multicollector transistors fed by carrier injection are used. A simplified (five masks) standard bipolar process is used resulting in a packing density of 400 gates/mm/SUP 2/ with interconnection widths and spacings of 5 /spl mu/m. The power-delay time product is 0.4 pJ per gate. An additional advantage is a very low supply voltage (less than 1 V). This, combined with the possibility of choosing the current level within several decades enables use in very low-power applications. With a normal seven-mask technology, analog circuitry has been combined with integrated injection logic (I/SUP 2/L).

Particle size and sol stability in metal colloids

Abstract: It is shown experimentally that the stability of metal sols depends on particle size. Sols with small particles are more stable against electrolyte coagulation than coarser suspensions. It is possible to separate metal particles of different radii by fractionated coagulation. Results are explained from the diminishedvan der Waals attraction between small particles. Consequences for the repeptization of metal sols and for the measurement ofHamaker constants are discussed. It is concluded that the smallness of the particles is a decisive factor for the stability of metal colloids.

Distribution of A‐Site and B‐Site Vacancies in (Pb,La)(Ti,Zr)O3 Ceramics

Abstract: It was shown experimentally that A-site vacancies predominate in La-substituted lead titanate-zirconate (PLZT) solid solutions. The formation of B-site vacancies is favored under increased PbO vapor pressure, but preparation of PLZT-perovskite phases with B-site vacancies only is impossible since the increase in the partial pressure of PbO is naturally limited by the condensation of liquid PbO at the grain boundaries of the ceramic.

Asthma due to inhaled chemical agents, tolylene di-isocyanate.

Abstract: Summary Four patients with asthma due to tolylene di-isocyanate (TDI) were tested by occupational type exposure to a polyurethane varnish and its TDI activator'. Late asthmatic reactions were given in two patients, the third gave an immediate reaction and the fourth gave a dual, immediate followed by late asthmatic, reaction. The reactions in the last two patients were inhibited by disodium cromoglycate. Two patients encountered the TDI in fumes from soldering polyurethane coated wire. The possibility of sensitization in conditions of limited exposure requires more frequent consideration as none of the four subjects tested gave histories of heavy exposure.

Optical properties of crystals of cuprous sulphides (chalcosite, djurleite, Cu1.9S, and digenite)

Abstract: Thin crystals of chalcosite, djurleite, Cu1.9S, and digenite have been prepared and their absorption and reflection spectra measured with polarized light between 400 and 1200 nm using an integrating microspectrophotometer. The spectra were worked out in terms of the absorption coefficient and the refractive index. The variation of the absorption coefficient with photon energy has been expressed quantitatively in terms of two types of simple expressions, representing absorption by free carriers and direct and indirect band-to-band transitions. Chalcosite crystals were prepared by topochemical reaction from thin single crystals of CdS having the c-axis in plane. The other phases were obtained by controlled extraction of copper from chalcosite at room temperature, leaving the sulphur lattice intact. Nous avons enregistre en lumiere polarisee les spectres d'absorption et de reflexion de minces cristaux de chalcosite, djurleite, Cu1,9S et de digenite, que nous avons nous-měme prepare. Ces spectres ont ete interpretes en termes de coefficient d'absorption et d'indice de refraction. La variation du coefficient d'absorption en fonction de l'energie photonique a ete exprimee quantitativement en expressions simples de deux types representant respectivement l'absorption par les porteurs libres et les transitions directes et indirectes bande a bande. Les spectres ont ete etudies entre 400 et 1200 nm avec un microspectrophotometre integrateur. Les cristaux de chalcosite ont ete prepares par reaction topochimique a partir de minces monocristaux de CdS ayant leur axe c dans le plan du cristal. Les autres phases ont ete obtenues par extraction contrǒlee du cuivre de la chalcosite a temperature ambiante, le reseau du soufre restant intact.

Fluidic function module for use in a system for constructing fluidic circuits

Abstract: A fluidic function module for constructing fluidic logical and/or analog circuit and which comprises a basic part including a plurality of fluidic circuit elements and a function connecting part which is arranged in contact with the basic part and in which passages have been formed which appropriately interconnect the input, output, supply and zero-pressure passages of the individual circuit elements, thus making the function module suitable for use as, for example, an AND, an OR, a universal or a storage module or as a function module having another desired function. The function connecting part is provided with a standard passage pattern. The user of the function module adapts the function connecting part to the intended use by removing, according to instructions given in tables, partitions from between different passages of the standard passage system and from between passages of the standard passage system and the ambient atmosphere at given grid locations and by subsequently assembling the function connecting part and the basic part to form a function module.

Low Melting Liquid Crystalline p,p'-di-n-Alkylazoxy- and Azobenzenes

Abstract: The analogous series of p,p'-di-n-alkyl-substituted azoxy- and azobenzenes are synthesized. These compounds show low melting points and nematic or smectic behaviour. The melting points are generally lower for the azoxy compounds than for the analogous azo compounds. A probable explanation is the non-planar conformation of the azoxy compounds as compared with the planar conformation of the azo compounds. The influence of a permanent dipole moment in the azoxy series and the absence of a permanent dipole moment in the azo series is investigated. The clearing point is increased by the presence of a permanent dipole moment. The dielectric constants parallel and perpendicular to the molecular axis are measured for some typical members of the series. For both series we find e‖ > e⊥, the difference being greater for the azo series than for the azoxy series.

Coercive force and stability of SmCo5 and GdCo5

Abstract: At low temperatures the compounds GdCo5 and SmCo5 decompose into the corresponding phases R2Co7 and R2Co17. This transformation is connected with the dependence of the coercive force of powder compacts on sintering temperature.

Compounds and pseudo-binary alloys with the CuAl2 (C16)-type structure IV. Superconductivity

Abstract: The superconductive transition temperatures, T c , of all 46 binary compounds having the CuAl 2 -type structure were measured, giving 25 superconductors above 0.07 K. Measurements were also made of T c , as well as of the room temperature values of the magnetic susceptibility χ and the thermo-electric power S in 16 pseudo-binary alloy systems having the C 16-type structure and containing partly transition metals, and partly non-transition metals as major constituents. Plotted against the valence electron concentration, T c , χ and S all show an oscillatory behaviour. The results can be explained with the aid of Brillouin zone effects.

Semiconductor memory elements

Abstract: A semiconductor memory element comprising a semiconductor substrate and an insulating layer thereon, a charge storage element located on a portion of the insulating layer and separated from the semiconductor substrate, and first device means for injecting hot electrons from the semiconductor substrate into the insulating layer portion to write a first charge state on the charge storage element and second device means for injecting hot holes from the semiconductor substrate into the insulating layer portion to write a second charge state on the charge storage element.

Methods and apparatus for submerged combustion (with air pollution control)

Abstract: Improvements in submerged combustion evaporators and heaters particularly adapted to the heating and evaporation of various heat sensitive solutions, including both methods and apparatus therefor; Improved apparatus and methods for the discharge of products of combustion from the combustion chamber of a submerged burner into and through the body of a heat-sensitive solution, said discharge handled in such manner as to reduce air pollution resulting from the practice of the submerged combustion process with respect to the given solution, as well as improve the effectiveness of the burner, per se, and the submerged combustion process.

Investigations on the LaCo5H and CeCo5H systems

Abstract: Pressure-composition isotherms and results of X-ray and magnetization measurements are presented for the pseudobinary systems CeCo5H and LaCo5-H In the latter system two orthorhombic hydrides are formed with hydrogen contents of ≈335 (β hydride) and ≈43 H (γ hydride) From ln p vs 1/T plots the heat of formation of the hydrides was derived: −108 and −77 kcal/mol H2, respectively In the CeCo5H system one orthorhombic (β) hydride is observed with a hydrogen content not exceeding 3 H CeCo 5 , At room temperature the primary hydrogen solubility in the hexagonal CeCo5 phase is relatively large Magnetization measurements (σ∥ − T) were performed on aligned powder specimens The magnetization of CeCo5 decreases only moderately (≈ 20%) due to the absorption of 22 CeCo 5 The σ∥ − T curves of the two LaCo5 hydrides are quite different, the β hydride being much more strongly dependent on temperature than the γ hydride (in the temperature range 4–320 K) From an extrapolation of the σ∥ curves the Co moments at 0 K are determined: 114 μB in the β hydride and 034 μB in the γ hydride (144 μB in LaCo5)

Growth, crystallography and dielectric properties of Bi2WO6

Abstract: The compound Bi2WO6 has been prepared as a ceramic and in single crystal form. Growth of Bi2WO6 single crystals from the melt by the Czochralski method produced boules as large as 20 mm in diameter by 60 mm long. On cooling to room temperature these boules invariably cracked, yielding for experimental investigations small prismatic rods bounded by (001) and (111) faces. The cause of the cracking phenomenon was found from DTA and dielectric property measurements to be a possible phase transformation occurring at 935°C, with an energy of 1 kcal/mole. A low-energy relaxation process was also detected in the temperature region 300-450°C. The low-iemperature modification of Bi2 WO6 is ferroelectric and crystallizes with the orthorhombic crystal structure B2cb(C172v), a -5.458 A, b = 5.438 A and c = 15.434 A. The structure of the higher temperature phase was not determined because of the severe recrystallization of the samples.

Image display cell

Abstract: An image display cell having a transparent wall portion, electrodes and an oxidizable redox substance and a reducible redox substance in an electrochemically inert liquid in contact with electrodes. The cell includes at least two electrodes which are in contact with a cell liquid in which a colourless viologen salt (formula I) has been dissolved. When a potential difference of at least 0.5 Volt is applied to the electrodes, this salt is reduced to a coloured insoluble compound which adheres to the cathode, so that the latter is coloured, thereby producing an image.

Device and holder therefor for inserting a hollow coupling member into bone marrow

Abstract: The invention relates to a device for inserting a hollow coupling member into the bone marrow of man or animals. Fluid may be supplied to the bone marrow through the inserted coupling member. The device according to the invention comprises an assembly of a striker-pin holder, a striker pin and a coupling member which is movably accommodated in an elongate housing and on which a force can be exerted by a source of energy provided in the device. When this force is exerted the striker pin and the coupling member are driven into the bone marrow, whereupon the coupling member can be detached from the remainder of the device.