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Notes: A new optical-lever based atomic force microscope is described in which the cantilever scans and is accurately tracked by a scanning focused spot. It can operate at forces below one nanoNewton over image areas greater than 100 μ×100 μ. It can be combined with optical microscopes of high numerical aperture and operated with the sample and cantilever in fluids. As examples of its applications, images of living cells in Petri dishes and a 6 in. (15.24 mm) silicon wafer are included.

Notes: Degradation of the gate oxide is often studied by stressing of metal-oxide-semiconductor (MOS) capacitors. Usually the MOS capacitor is stressed in accumulation to avoid the complications due to a voltage drop across the depletion layer if stressed in inversion. High field stressing studies for MOS capacitors with the silicon in inversion are presented in this article. Our observations show that in this mode, silicon properties (mainly minority carrier generation lifetime) play an important role.

Notes: Single crystals of mixed methyl-(2,4-dinitrophenyl)-aminopropanoate (MAP): 2-methyl-4-nitroaniline (MNA) have been grown from solution using a 40:60 mixture of ethanol and ethyl acetate. Formation of an equimolar complex is confirmed by x-ray diffraction studies. The complex crystallizes in the monoclinic space group P21. The lattice parameters are a=6.9196(±0.005) A(ring); b=7.673(±0.008) A(ring); c=18.554(±0.001) A(ring); and β=92.547(±0.006)0. b axis is the unique twofold axis and there are two molecules per unit cell. The molecules stack along the b axis with MAP atop MNA atop MAP. Details of the molecular orientation are given. The Raman spectra also indicate that the parent molecules are not disturbed in the process of crystallization. The second harmonic generation efficiency of the new material for 1064 nm laser radiation is observed to be the same as that of MAP but lower than that of MNA. The latter is attributed to the absorption at 532 nm in the mixed crystal. The melting point determined by differential scanning calorimetry is 104.30 °C.

Notes: The kinetics of plasma oxidation of silicon at constant anodization current have been investigated. Oxidation was performed in an inductively coupled rf plasma anodization setup. The oxidation model is based on the assumption that the oxidant from the plasma is neutral atomic oxygen which captures an electron inside the oxide and forms a negative oxygen ion (O−). The O− ion then hops through interstitial sites in the oxide due to the high drift field during the anodization. A photon-assisted oxidation mechanism is assumed to occur at the SiO2/Si interface in which the energy to break Si—Si bonds at the interface is supplied by UV photons which are generated in the plasma. Based on these assumptions an analytical model was developed that successfully explains the dependence of oxidation rate on the gas pressure in the plasma, which was not explained by previous investigators. It has been shown that during constant current anodization, the space-charge effects inside the oxide are negligible. It was found that the oxidation rate shows a weak temperature dependence with a thermal activation energy of 0.04 eV. The data on oxide thickness versus the oxidation time were found to be in good agreement with the theory.

Notes: High-field effects in metal-oxide-semiconductor capacitors have been studied in detail. A comprehensive set of experiments, stressing identically fabricated capacitors on both P-type and N-type silicon, both in accumulation and in inversion, has been made to study defect generation in the oxide at high fields. There is clear experimental evidence that both bulk hole and electron traps are generated under all stress conditions. High-field prebreakdown properties depend mainly upon the dynamics of generation of traps, trapping and detrapping at these and in previously existing traps. It has been found that of several processes, some dominate, depending upon the type of silicon and polarity during stressing, and this is also true for the final breakdown mechanism. In this paper the dominant mechanisms are identified for each of the field stress conditions that have been studied.

Notes: Processing induced stacking faults below reoxidized nitrided oxides have been observed by electron beam induced current (EBIC) imaging and by secondary electron imaging after preferential etching. Comparative studies of stacking fault lengths with those of dry and nitrided oxides show that the growth rates of stacking faults are anomalously high during reoxidation. A large proportion of these stacking faults show electrical activity in EBIC images. This is reflected in the degradation of effective generation lifetimes as seen in transient capacitance measurements.

Notes: Abstract. Agricultural soils, having been depleted of much of their native carbon stocks, have a significant CO2 sink capacity. Global estimates of this sink capacity are in the order of 20-30 Pg C over the next 50-100 years. Management practices to build up soil C must increase the input of organic matter to soil and/or decrease soil organic matter decomposition rates. The most appropriate management practices to increase soil C vary regionally, dependent on both environmental and socioeconomic factors.In temperate regions, key strategies involve increasing cropping frequency and reducing bare fallow, increasing the use of perennial forages (including N-fixing species) in crop rotations, retaining crop residues and reducing or eliminating tillage (i.e. no-till). In North America and Europe, conversion of marginal arable land to permanent perennial vegetation, to protect fragile soils and landscapes and/or reduce agricultural surpluses, provides additional opportunities for C sequestration.In the tropics, increasing C inputs to soil through improving the fertility and productivity of cropland and pastures is essential. In extensive systems with vegetated fallow periods (e.g. shifting cultivation), planted fallows and cover crops can increase C levels over the cropping cycle. Use of no-till, green manures and agroforestry are other beneficial practices. Overall, improving the productivity and sustainability of existing agricultural lands is crucial to help reduce the rate of new land clearing, from which large amounts of CO2 from biomass and soil are emitted to the atmosphere.Some regional analyses of soil C sequestration and sequestration potential have been performed, mainly for temperate industrialized countries. More are needed, especially for the tropics, to capture region-specific interactions between climate, soil and management resources that are lost in global level assessments.By itself, C sequestration in agricultural soils can make only modest contributions (e.g. 3-6% of total fossil C emissions) to mitigating greenhouse gas emissions. However, effective mitigation policies will not be based on any single ‘magic bullet’ solutions, but rather on many modest reductions which are economically efficient and which confer additional benefits to society. In this context, soil C sequestration is a significant mitigation option. Additional advantages of pursuing strategies to increase soil C are the added benefits of improved soil quality for improving agricultural productivity and sustainability.

Notes: A mutation breeding programme using gamma rays and ethyl methane sulphonate (EMS) was carried out for genetic conversion of narcotic ‘opium poppy’ into non-narcotic ‘seed poppy’. Two families contained 31 latexless (opiumless) and 23 partial latex-bearing plants which were identified in the M2 and confirmed in the M3 generations by the ‘ray-pluck’ method. Thin-layer chromatography (TLC)-densitometry of powdered capsule hulls (straw) from 22 representative plants also revealed that none of the five opium alkaloids (morphine, codeine, thebaine, papaverine and narcotine) was present in the straw. Six plants also possessed high seed yield (4.0–5.66 g/capsule vs. 3.39 g for control) and seven had a high seed oil content (50.7-53.5%). The best mutant genotype, LL-34 of the family C1-Comb-113-2, with 5.66 g/capsule seeds containing 52.6% oil was designated as cv. ‘Sujata’. This, perhaps the world's first opiumless and alkaloid-free seed poppy cultivar, offers a cheap and permanent (fundamental) solution to the global problem of opium-linked social abuse. Simultaneously, it serves as a safe and potential food crop with protein-rich seeds and healthy unsaturated seed oil.