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Mixtures of uranium mononitride and molybdenum have been studied between the temperatures of 2100 and 2700 °C. By means of several melt specimens the liquidus line and the eutectic line have been determined. Under a pressure of 650 torr nitrogen for the eutecticum, a composition of 58 wt % molybdenum and 42 wt % uranium nitride was obtained at a eutectic temperature of 2400 ± 20 °C. Particularly in uranium-rich specimens the components of the uranium-rich phase (U2Mo containing nitrogen) were observed. Additional experiments at higher and lower nitrogen pressures show displacements of the eutectic composition and temperature. A few special experiments in the analogous system uranium mononitride-tungsten were carried out and the resulting composition for the eutecticum, with 96 wt % uranium nitride, was found to lie near the pure uranium nitride. One can suppose that the eutectic melting point is at about 2700°C.

When maize leaves are inoculated with conidia of Colletotrichum graminicola the uninucleate, single-celled spores swell and undergo mitosis. In each spore a septum forms between the daughter nuclei and one cell of the resulting two-celled structure germinates to produce an appressorium with an electron-dense outer cell wall. Prior to penetration a new, inner, electron-lucent wall forms around the basal portion of the appressorium. During penetration, which occurs 6 to 9 h after inoculation, the outer dense wall of the appressorium disappears, without evidence of mechanical disruption, in the area of the developing infection peg. At all stages of infection the infection peg and the hypha which develops from it are enveloped by a distinctive, electron-lucent cell wall which is continuous with the inner wall of the appressorium. During penetration only the cuticular layers of the host cell wall are depressed inward. Dense host reaction products (papillae) are formed and the plasma membranes are disrupted before cell walls are completely penetrated and also in cells adjacent to those invaded by the fungus. The infection process is completed within 12 h by the formation of a septum between the appressorium and the swollen infection hypha.

Zusammenfassung Es wurden Untersuchungen im System Uranmonokarbid-Wolfram mit Hilfe metallographischer und rontgenographischer Methoden sowie mit der Mikrosonde und dem Elektronenmikroskop durchgefuhrt. Die peritektische Reaktion wurde bestatigt, die periktektische Temperatur zu 2170 ± 10 °C gefunden. Bei dieser Temperatur betragt die Loslichkeit von Wolfram im Uranmonokarbid etwa 5 Gew.-% W. Die beobachtete Phase UWC2−x hat eine monokline Struktur isomorph der UMoC1,7-Phase und zwar mit folgenden Gitterparametern: a = 5,624 ± 0,002 A , b = 3,240 ± 0,001 A , c =11,640 ± 0,003 A und β=109,6 ± 0,1° . Die Temperaturabhangigkeit der Loslichkeit von W in UC wird angegeben. UC mit wenigen % Wolfram scheint chemisch bestandiger zu sein als reines UC.

The self-diffusion of uranium in uranium dicarbide, UC 2 , was measured between 1670 and 2500 K using the α-energy degradation method with the thin layer condition and U-233 as tracer. The activation enthalpy was 5.7 ± 0.2 eV. A discontinuity was indicated at ≈ 2050 K, the transition temperature of α-UC 2 to β-UC 2 .

The petitioners’ railway was constructed in Hungary under a charter granted by the government in 1884. By a subsequent agreement, duly approved by the Hungarian Government, the operation of the railway was leased to the Siidbahn Co. for the entire period of the concession, on terms providing for the division of the receipts in certain percentages between the two companies.

Power systems must be operated within limits that will ensure adequate generation and transmission capacity to avoid cascading. In developing a set of operating limits, it is important to do so within a general framework in order to ensure that the operating objectives are met. In this regard, a set of general guidelines are presented below: 1. The integrity of the transmission system will be maintained at all times without planned internal separation. 2. Maximum reasonable assistance will be given to adjacent systems experiencing difficulty. However, such assistance will be terminated ?without opening interconnection circuits ?when the reliable operation of the assisting system is impaired. 3. The system should be operated so that the occurrence of the next single contingency (outage of tower, circuit, unit, breaker, bus, etc.) will not result in a cascading loss of the bulk transmission system. The single contingency is continually geared to the current state of the system and reflects maintenance and forced outage events as they occur. In addition, when evaluating overload contingencies, the time to relieve the stress must be compared to the permissible degree of overload. 4. When the system experiences a generation-load imbalance, the principles of sound interconnected operation will be maintained by bringing under control an unscheduled tie-line power flow condition as quickly as possible.

Politis Nicolas. Le transfert des populations. In: Politique étrangère, n°2 - 1940 - 5ᵉannée. pp. 83-94.

Earlier investigations on the survival of leukocytes in whole blood preserved in acid citrate dextrose (ACD) solution at 4°C. and in tissue cultures at 37°C. indicated that granulocytes were rapidly killed, presumably as a result of the toxicity of citrate.1 2 3 4 These conclusions were based on the loss of motility, a decrease in phagocytic ability and a marked decrease in the number of granulocytes. Mononuclear leukocytes had been noted to persist in bank blood for several weeks, but owing to the lack of technics for the assessment of the viability of these cells, it was generally assumed that they rapidly became . . .

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After annealing uranium mononitride and UN-Momixtures on molybdenum supports above 2000 °C under a vacuum of 10−2-10−5 torr, a molybdenum content of about 0.23 wt % in UN along with an increase of the UN lattice parameter observed at room temperature was observed. Though the appearance of substoichiometric uranium mononitride seems, in principle, to be possible, the cooling rate may not be sufficient to freeze in this condition. The decomposition of UN initiated at high temperatures under vacuum results in a γ-U-Mo-phase which can be detected by metallographic and X-ray methods; by microprobe analysis about 21–22 wt % of Mo and 78 wt % of U were detected. Moreover, the microanalytical studies showed up appreciable amounts of nitrogen (about 1 wt %). On the molybdenum sheet supports, UO2-crystals orientated in [111] direction can be detected subsequent to annealing at 2400 °C under N2 and X-ray diffraction also revealed a UN2−x-phase with a lattice constant a0 = 5.344 A. The X-ray studies with annealed UN-tungsten specimens up to 2400 °C do not give indications on possible reactions or solubilities. Changes in the lattice parameters could not be observed. After annealing of UN-ThO2-mixtures carried out on tungsten-sheet- and ThO2 supports no remarkable change in the UN lattice parameter is detected up to 2400 °C under 500 torr of nitrogen. After annealing on molybdenum supports a slight change Δa0 = 0.005 A is measured following annealings at 1750 °C and 2000 °C under vacuum. However, the UO2 impurities form a solid solution together with thorium oxide, as can be observed by the variation of the lattice constants. The upper temperature limits of satisfactory compatibility strongly depend on the annealing atmosphere. In the case of UN-Mo under 10−5 torr of N2 it is at 1550 °C and rises to about 2300 °C under 300 torr of N2. Slightly higher temperatures are applicable to UN-W.