InAs-AlSb quantum wells in tilted magnetic fields

InAs-AlSb quantum wells are investigated by transport experiments in magnetic fields tilted with respect to the sample normal. Using the coincidence method we find for magnetic fields up to 28 T that the spin splitting can be as large as 5 times the Landau splitting. We find a value of the g-factor of about 13. For small even-integer filling factors the corresponding minima in the Shubnikov-de Haas oscillations cannot be tuned into maxima for arbitrary tilt angles. This indicates the anti-crossing of neighboring Landau and spin levels. Furthermore we find for particular tilt angles a crossover from even-integer dominated Shubnikov-de Haas minima to odd-integer minima as a function of magnetic field

Three-Omega Thermal-Conductivity Measurements with Curved Heater Geometries

The three-omega method, a powerful technique to measure the thermal conductivity of nanometer-thick films and the interfaces between them, has historically employed straight conductive wires to act as both heaters and thermometers. When investigating stochastically prepared samples such as two-dimensional materials and nanomembranes, residue and excess material can make it difficult to fit the required millimeter-long straight wire on the sample surface. There are currently no available criteria for how diverting three-omega heater wires around obstacles affects the validity of the thermal measurement. In this Letter, we quantify the effect of wire curvature by performing three-omega experiments with a wide range of frequencies using both curved and straight heater geometries on SiO$_2$/Si samples. When the heating wire is curved, we find that the measured Si substrate thermal conductivity changes by only 0.2%. Similarly, we find that wire curvature has no significant effect on the determination of the thermal resistance of a $\sim$65 nm SiO$_2$ layer, even for the sharpest corners considered here, for which the largest measured ratio of the thermal penetration depth of the applied thermal wave to radius of curvature of the heating wire is 4.3. This result provides useful design criteria for three-omega experiments by setting a lower bound for the maximum ratio of thermal penetration depth to wire radius of curvature.Comment: 4 pages, 3 figure

Using synchrotron techniques to understand plant diseases stripe rust and wheat

Non-Peer Reviewe

Physicochemical Characteristics of Cobalt Selenides & Their Catalytic Activities

775-77

Influence of various training systems on yield and quality of Muscat Hamburg grapes

Effect of different training systems on the performance of Muscat Hamburg was studied as regards yield and quality for six years. Although the space allotted and fertilizer applied per vine were the same, the vines trained on bower system gave yields five times as high (9.0 kg/vine) as those trained on head system (1.8 kg/vine). Unilateral Kniffin, unilateral telephone, bilateral telephone and bilateral Kniffin gave yields of 5.4, 5.6, 5.8 and 6.7 kg/vine, respectively. There was no measurable effect on quality of fruit.Der Einfluß verschiedener Erziehungssysteme auf Ertrag und Qualität der RebsorteMuskat HamburgIn einem sechsjährigen Versuch wurde der Einfluß verschiedener Erziehungssysteme auf die Ertrags- und Qualitätsleistung von Muskat Hamburg verfolgt. Obwohl die Fläche und die Düngergabe je Rebe durchweg gleich waren, erbrachten die Reben bei Pergolaerziehung im Durchschnitt den fünffachen Ertrag wie bei Kopferziehung (9,0 kg/Rebe gegenüber 1,8 kg). Bei einseitiger Kniffin-, einseitiger „Telephon"-, zweiseitiger „Telephon"- bzw. zweiseitiger Kniffin-Erziehung wurden Durchschnittserträge von 5,4, 5,6, 5,8 bzw. 6,7 kg/Rebe erzielt. Ein meßbarer Einfluß der Erziehungsform auf die Beerenqualität lag nicht vor

Effect of plant density on vine growth, yield, fruit quality and nutrient status in Perlette grapevines

Studies on the effect of plant density on vine growth, nutrient status, yield and quality of the grape cv. Perlette were carried out during 1980, 1981 and 1982. Vine growth measured in terms of shoot length, trunk girth and pruning weight as weil as the level of the nutrient elements N, P, K, Fe, Mn, Zn and carbohydrates were highest at the maximum spacing i. e. 3.0 x 3.0 m and decreased with an increase in the plant density. Most of the nutrients were high either in early spring or during the rainy season. The average yields per vine and per ha were highest at 3.0 x 3.0 m and 2.0 x 2.0 m spacing, respectively. No significant differences were observed in the various quality parameters of the fruit under various plant densities. Under the prevailing agro-climatic conditions optimum yield per ha of Perlette grapes trained on head system can be obtained by planting the vines at 2.0 x 2.0 m spacing