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This study demonstrates the use of digital image processing for the spatial pattern recognition and characterisation of Ni concentrations in topsoil in Europe. Moving average smoothing was applied to the TIN-interpolated grid model to suppress small irregularities. Digital image processing was applied then to the grid. Several NE-SW, E-W and NW-SE oriented features were revealed at the continental scale. The dominant NE-SW linear features follow the Variscan and Alpine orogenies. The highest variability zones are in the Alps and the Balkans where mafic and ultramafic rocks outcrop. A single major E-W oriented north-facing feature runs along the last continental glaciation zone. This zone also coincides with a series of local maxima in Ni concentration along the glaciofluvial deposits. The NW-SE elongated features are located in the Pyrenees, northern Italy, Hellas and Fennoscandia. This study demonstrates the advantages of digital image processing analysis in identifying and characterising spatial geochemical patterns unseen before on conventional colour-surface maps.

The demand for ‘high-tech’ element resources (e.g., rare earth elements, lithium, platinum group elements) has increased with their continued consumption in developed countries and the emergence of developing economies. To provide a sound knowledge base for future generations, it is necessary to identify the spatial distribution of critical elements at a broad-scale, and to delineate areas for follow-up surveys. Subsequently, this knowledge can be used to study possible environmental consequences of the increased use of these resources. In this paper, three critical industrial elements (Sb, W, Li) from low-sampling density geochemical mapping at the continental-scale are presented. The geochemical distribution and spatial patterns have been obtained from agricultural soil samples (Ap-horizon, 0–20 cm; N = 2108 samples) collected at a density of 1 site per 2500 km2 and analysed by ICP-MS after a hot aqua regia digestion as part of the GEMAS (GEochemical Mapping of Agricultural and grazing land Soil) soil-mapping project in 33 European countries. Most of the geochemical maps show exclusively natural background element concentrations with minor, or without, anthropogenic influence. The maximum extent of the last glaciation is marked as a discrete element concentration break, and a distinct difference occurs in element concentration levels between the soil of northern and southern Europe, most likely an effect of soil genesis, age and weathering. The Sb, W and Li concentrations in soil provide a general overview of element spatial distribution in relation to complexity of the underlying bedrock and element mobility in the surface environment at the continental-scale. The chemical composition of agricultural soil represents largely the primary mineralogy of the source bedrock, the effects of pre- and post-depositional chemical weathering, formation of secondary products, such as clays, and element mobility, either by leaching or mineral sorting. Observed geochemical patterns of Li, W and Sb can be often linked with known mineralisation as recorded in the ProMine Mineral Database, where elements in question occur either as main or secondary resources. Anthropogenic impact has only been identified locally, predominantly in the vicinity of large urban agglomerations. Unexplained high element concentrations may potentially indicate new sources for high-tech elements and should be investigated at a more detailed scale.

Background & aims: Optimal nutritional therapy for energy and protein in critically ill, mechanically ventilated patients can be defined as: providing calories matched with the measured energy expenditure and delivery of protein in an amount of 1.2-1.5 g/kg pre-admission weight/day. Several enteral nutritional products are available with different energy/protein proportions. We developed an algorithm to choose the nutritional formula that combines optimal energy and protein supply for individual patients. Methods: The energy and protein values of three nutritional formulas were used together with an aimed provision of 1.2-1.5 g protein/kg/day to construct a nomogram. From that, an algorithm followed, which was tested retrospectively in 203 mechanically ventilated patients with a normal BMI and known values for energy expenditure and weight. Results: In the nomogram cut-off points for energy/weight ratios were: 19.0-23.8 for a normal energy/high protein formula, 23.8-29.8 for a high energy/high protein formula and 30-37.5 for the normal energy/normal protein formula. The algorithm uses energy expenditure/body weight ratio of the patients to choose one of the three formulas. This resulted in an adequate provision of protein in 93% of the patients. Conclusion: The algorithm leads to provision of adequate amounts of protein and energy in the majority of critically ill, mechanically ventilated patients.

A new chiral lithium amide has been designed starting from ( S )-proline. This new chiral lithium amide has been used for asymmetric deprotonation/ring opening of cyclohexene oxide to give ( S )-2-cyclohexen-1-ol in 88% yield and 78% enantiomeric excess. NMR studies of the lithium amide and the ligand–substrate complex are also presented.

We show, using several proxies, that the real exchange rate in Kenya has moved in accordance with the dependent economy model since 1975. The adjustment policy supported by the International Monetary Fund (IMF) in the first half of the 1980s led to a rise in the Kenyan real exchange rate and an improvement of its external position. Macroeconomic policy since 1986, however, has resulted in a deterioration of the external position and is likely to result in a reduction in the real exchange rate in the near future.

The induction of specific macrophage cytotoxicity by allo-sensitized T cells in vitro is shown to be independent of the presence of lipopolysaccharide (LPS). This contrasts with the induction of macrophage cytotoxicity by Macrophage Activating Factor (MAF). The specific macrophage cytotoxicity could be induced in LPS-free medium (less than 1 ng/ml). Addition of LPS to the macrophages did not increase the cytotoxicity. Addition of LPS-binding polymyxin B to the macrophages before and during the induction of cytotoxicity did not reduce the specific macrophage cytotoxicity. Macrophages obtained from the LPS-unresponsive mouse strain C3H/Hej were rendered cytotoxic by the allo-sensitized lymphocytes to the same extent as the macrophages from LPSresponsive C3HeB/Fe and C57BL mice. This indicates that the induction of macrophage cytotoxicity by MAF is different from the induction of specific macrophage cytotoxicity by Specific Macrophage Arming Factor (SMAF).

Experimental investigations of the photovoltaic properties of metal-silicon Schottky barriers are reported, in which edge collection of the photocurrent is dominant as in the majority-carrier grating solar cells proposed by Green. Both elemental metals and alloy Schottky electrodes, and both crystalline and semicrystalline cast silicon have been studied. The superposition principle for dark currents and photocurrents is shown unambiguously to be violated, and the effects of grain-boundary recombination and shunt resistance are identified. Limitations to the operation of these devices above the semiempirical limit of continuous Schottky barrier solar cells is seriously compromised by enhanced space-charge recombination current. This results from the large photocurrent densities for low contact area/active area ratios. The treatment of the space-charge recombination mechanism under optical illumination follows the normal Sah-Noyce-Shockley approach, but we introduce here a built-in “recombination potential” to encompass the non-zero recombination for short-circuit conditions.

Short-channel MOS transistors exhibit a drain current saturation behaviour different from that of longer channels. By comparing measured and calculated characteristics it is shown that the current increase can be successfully interpreted as a threshold voltage shift proportional to the drain voltage. A circuit model is derived which takes into account the above effect and includes an improved saturation mechanism. Compared with existing models the present one yields smaller deviations between measured and calculated characteristics and does not need non-physical parameters values.

Zusammenfassung Die Intensitat des Fluoreszenzlichtes von einigen Sulfidphosphoren (ZnS–Cu, Zn–Ag, ZnSCdS–Ag, ZnSMnS) wird gemessen in Abhangigkeit der Energiedichte (in Watt/cm2 des) erregenden ultravioletten Lichtes. Es zeigt sich, dass bei Energiedichten von der Ordnung von 5 W/cm2, bei gleichbleibender Totalenergie, das Fluoreszenzlicht der genannten Substanzen um 5–10% niedriger ist als bei einei 100-fach kleineren Energiedichte. Uranglas, K-Uranylsulfatkristalle und Fluoreszeinlosung zeigen den Effekt nicht.

Zusammenfassung Unter Zugrundelegung einer hyperbolischen Zeitformel wird aus Versuchen uber die Abklingung der Rontgenstrahlenlumineszenz bei einem Zink-Cadmium-Sulfid eine Zeitkonstante ϑ = 3. 10−4 Sek., unabhangig von der Rontgenintensitat gefunden. Hieraus folgt, dass die einzelnen Rontgenquanten (50kV) unabhangig voneinander ein kleines Volumen des Kristalls anregen. Unter Benutzung einer fruheren Bestimmung der Konstante des bimolekularen Gesetzes der Rekombination wird nachher als obere Grenze fur das Gesamtvolumen einer durch ein Quant freige machten Elektronenwolke 6.10−15 cm3 gefunden. Die Abklingdauer nimmt unter Einfluss eines Nickel-“killers” ab. Willemit und Cadmiumborat haben eine exponentielle Abklingung mit τ ∼ 0,005 Sek.

Sommaire Au moyen d'un tube multiplicateur et d'un oscillographe a rayons cathodiques on examine la croissance et la decroissance de la photoluminescence du sulfure de zinc (p.e. ZnS–Cu), illumine periodiquement pendant 5 millisec. La source lumineuse est une lampe a mercure capillaire et l'energie de la lumiere ultraviolette excitatrice a peu pres monochromatique est de l'ordre 0,5 W/cm2. On discute un mechanisme bimoleculaire pour la production de la lumiere, combine avec des etats metastables pour rendre compte de la phosphorescence de longue duree. Quelques observations sur le verre d'urane sont ajoutees.

Summary From the yield of the neutrons produced by D-ions impinging upon targets of D3PO4, Li, Be, C as measured by Amaldi, Hafstad and Tuve, the effective cross-sections σ for D, Li, Be and C as a function of the velocity ν of the projectile are derived, making use of Mano's data on the range of charged particles in air and on the atomic stopping power of the elements. It is proved that with sufficient approximation σ ( : ) v m e − y 0 > m > − 2 y = 2 π 137 z Z c v With the aid of this relation it is possible to extrapolate the yields, as found by Amaldi, Hafstad and Tuve, to lower energies. It is shown that the results of Ladenburg c.s., Scherrer, Kallmann, and others fit a curve with m = — 1. It proved necessary to recalculate the conversion factor from a compound target into a pure-D target in some cases, making use of the relation a t o m i c s t o p p i n g p o w e r ( : ) Z

Zusammenfassung Das An- und Abklingen der Lumineszenz von verschiedenen Kristallen bei periodischer Beleuchtung mit ultraviolettem Licht von grosser Intensitat wird im Anschluss an fruhere Untersuchungen weiter verfolgt. Zur Beobachtung kamen Kristalle von ZnS-Ag, ZnS-Cu, ZnSCdS-Ag, ZnSMnS CaWO 4 -Sa, Zn 2 SiO 4 -Mn. Fur Zn 2 SiO 4 -Mn wird, ausgehend von den von Nottingham mitgeteilten Daten uber Sattigung bei Elektronenanregung, die Anzahl der Zentren pro Volumeneinheit und der Wirkungsquerschnitt eines Zentrums berechnet. Der Einfluss von verschiedenen experimentellen Umstanden auf die Form der An- und Abklingkurven der Sulfidphosphore wird diskutiert. Endlich werden einige Beobachtungen an ZnSCdS Einkristallen bei monochromatischer Beleuchtung unter dem Mikroskop beschrieben.

The integral equation for the number na of excited atoms in a discharge tube (resonance level) n.n e .I I −n a .n e .I II =n a .A−n ∫ ρ(v)b(v)dv was formerly approximately solved in replacing it by a second order differential equation. This procedure has partly lead to faulty results. It is pointed out that the difficulty arises from the divergence of the integral denoted by ∫ F(r) r 2 dr. It is shown that, when expressing the lightproduction by a surface integral, the error arising from insufficient knowledge of na is larger than when taking the volume integral of the left side of (1). The behaviour of the D lines of sodium (self reversal, intensity-ratio as a function of vapour pressure) may be explained on a similar base as before although the reasoning must be slightly changed.

Zusammenfassung Die von O. Halpern und Mitarbeitern gefundene Formel fur die Albedo β = 1− 4 ✓3 1 ✓N wird erganzt, indem der folgende Term der Reihenentwicklung abgeschatzt wird. Die Formel lasst sich dann schreiben: β = 1− 4 ✓3 1 ✓N + 2.86 N

Summary The radiation of a super high pressure mercury lamp with an input of 460 W and 10 mm length of the discharge, is measured in two ways; (1) by determining the energy given off to the cooling water, (2) directly by means of a thermopile. Both methods give sufficiently concordant results, from which it is derived that about 50% of the energy input is radiated. ]For an ordinary high pressure mercury lamp with quartz tube and an input of 26 W per cm of positive column, the radiation amounted to 27%, corresponding to about 39 Lumen/watt (cathode losses excluded). This results was obtaind by measurement with a thermopile and a water-filter.

Some remarks on the definition of standard illuminant A, with special reference to the (provisional) CIE recommendation, as formulated during the CIE meeting, Stockholm 1951.