Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 74 (1993), S. 3608-3610 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report a study of tip artifacts in atomic force microscope (AFM) images of thin film surfaces. Specifically, a troublesome artifact that occurs when an AFM tip images surface features with a radius of curvature less than the apex of the tip. These artifacts are not easily detected, since the affected AFM images are similar to those expected for a thin film with a columnar microstructure. In a study of 23 thin films, we found that for a significant fraction, the AFM image was affected by this type of tip artifact. In the worst cases, the AFM images consisted almost entirely of images of the AFM tip. We discuss a simple technique to determine the extent of these tip artifacts.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Carrier profiling of a 400 nm complementary metal–oxide–semiconductor device has been accomplished by combining metal–semiconductor capacitance–voltage profiling techniques with two-dimensional scanning probe microscopy. When a metal probe is brought into contact with a semiconductor, a space-charged depletion region and therefore a capacitor is formed at the junction. By applying a small ac voltage, the voltage derivative of the contact capacitance can be measured with a lock-in amplifier. The amplitude of the derivative signal is a function of the carrier concentration, and the sign gives the type of carrier. The present work concentrates on the two dimensional (2D) carrier profiling of a 400 nm metal–oxide–semiconductor field effect transistor. The results demonstrate that this technique is capable of quantitative 2D characterization of semiconductor devices. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 65 (1994), S. 3378-3381 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A high-resolution noncontact scanned probe technique has been developed for sampling the internal signals of an operating integrated circuit. The signal waveform is extracted by sensing the localized electrostatic force between a small probe and point on the circuit being measured. A heterodyne approach is used to enable the sampled measurement of high-frequency digital or analog waveforms. In conjunction with a nulling method, the technique is capable of accurate signal measurement without complex calibration or probe positioning, and can be performed over passivated structures. Measurement of digital and analog signals is demonstrated with a voltage accuracy of less than 100 mV.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Grass and forage science 30 (1975), S. 0 
    ISSN: 1365-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Forage diets were prepared from ryegrass (non oestrogenic control) and from red clover as pellets or as unwilted silage. Each diet was fed to separate groups of 20 Border Leicester × Cheviot ewes for three weeks prior to the introduction of the ram, and for two cycles after mating. Subsequently, all three groups of ewes were fed in a similar manner until lambing and the reproductive performance of the ewes was measured. The control diet was prepared by barn drying a primary growth crop of perennial ryegrass, Lolium perenne cv S23. Tetraploid red clover, Trifolium pratense cv. Hungarpoly, was harvested as a first regrowth crop and the pelleted diet prepared by high temperature drying, grinding (2 mm screen) and pelleting. The silage was prepared without wilting. The level of formononetin in the red-clover silage was three times that in the dried red-clover pellets.Compared with the control grass diet, the feeding of red clover in either form significantly reduced (P〈0·001) the number of lambs born. The incidence of barrenness was higher (P〈0·001) for ewes fed red-clover silage compared with red-clover pellets and the control diet. The rate of twinning was significantly (P〈0·001) higher for the ewes fed the control grass diet than for either of the red-clover diets. The resultant lambing percentages were 190,165, and 100% for the control grass, red-clover pellet and red-clover silage treatments. In flock management, both the grazing of red clover and the feeding of red-clover pellets or silage, prior to and during mating, should be avoided.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Grass and forage science 40 (1985), S. 0 
    ISSN: 1365-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: With its potential for high yields and high animal output, lucerne appears to be an underexploited crop in British agriculture. In this paper an attempt is made to assess the prospects for expansion of the area of lucerne in Britain from an economic viewpoint, concentrating on lucerne as a conservation crop. Under good management lucerne is shown to have lower production costs than grass and its inclusion in the diet of dairy cows, but not beef cattle, could significantly lower winter feed costs. However, under apparently similar growing conditions, lucerne yields on different farms vary significantly, ranging from 9 to 13 t dry matter ha−1 a−1. At the lower yields, the economic attraction of growing and feeding lucerne in place of grass is small. Moreover, since potential lucerne production is concentrated in the south and east of Britain, lucerne competes with other arable crops. For lucerne to offer a gross margin per unit area comparable with these, the price for conserved lucerne would have to be set at a level at which dairy farmers would derive little economic advantage from feeding it. Thus, although lucerne is a forage crop with some potential, at present it is likely to offer economic possibilities only where producers can combine high yields with on-farm utilization of the crop.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Grass and forage science 39 (1984), S. 0 
    ISSN: 1365-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: In view of the revived interest in sainfoin, an economic assessment of the prospects for an expansion of its area in Britain has been attempted. It is estimated that potentially it could be grown on 950 × 103 ha of the agricultural area of England and Wales, though it is unlikely in the near future that it would exceed 20 × 103 ha, even if economic conditions were favourable. Comparison of the energy and protein yields of sainfoin, red clover and lucerne under conservation management indicates that one of the attractions of sainfoin is its high protein content. However, an assessment of the costs of production and utilization of sainfoin indicate that, for it to be a more widely used legume, sustainable dry matter (DM) yields would need to be increased by 35% to about 11.5 × 103 kg DM ha−1. At the same time, although growing sainfoin as a mixture with grass appears to improve the economic attractiveness of the crop, silage production costs (kg DM)−1 are still about 15% lower on pure grass swards. However, trials in the UK, Canada and Rumania have shown that, compared to current UK levels, sainfoin yields can be significantly increased.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Grass and forage science 26 (1971), S. 0 
    ISSN: 1365-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Two experiments were conducted to measure the voluntary intake and digestibility of (a) primary growth and (b) regrowth of diploid (S22) and tetraploid (Tetila tetrone) varieties of Italian rye-grass (Lolium muitifiorum): Sl00 white clover (Trifolium repens) was included as an additional treatment in the second experiment with the re-growth herbage diets. Mature adult wether sheep, housed indoors in digesdhility crates, were fed individually on fresh herbage cut daily from late April to early June (primary growth) and in early Septemher (regrowth). The yield, digestihility, nitrogen and soluble–carhohydrate contents of the two ryegrass varieties were similar during the primary growth stage. Intake-digestibility relationships for the graces were positive, linear and different (P=0.05). The voluntary intake of diploid ryegrass was approximately 14% higher than that of tetraploid ryegrass of the same digestibility. With regrowth herbage the digestibility and voluntary intake of white clover was higher than both the Italian ryegrasses. The digestihility of the regrowth tetraploid was 6% units higher than the diploid variety, but there was no difference in the voluntary intake of digestible organic matter between the varieties at the regrowth stage. The intake of regrowth herbage was higher thaa that of primary growth herhage of similar digestihility.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 57 (1990), S. 28-30 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have directly imaged n-alkane layers adsorbed at the liquid/graphite interface using a scanning tunneling microscope. The layers possessed a high degree of two-dimensional ordering. The adsorbate was observed to enhance the tunneling current, and the atomic structure of the images was dominated by features associated with the substrate. These systems are excellent vehicles for studies concerning the imaging mechanism of adsorbed organic layers because of their stability and simplicity.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 65 (1989), S. 2457-2463 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Silicon dioxide films were deposited on crystalline silicon substrates by electron cyclotron resonant (ECR) microwave plasma-enhanced chemical vapor deposition (PECVD). Films were grown on Si〈100〉 substrates at temperatures of 140–600 °C, flow rates of 0.5–10 sccm SiH4, 10–30 sccm O2, and at a pressure of 10−3 Torr. Infrared absorption spectroscopy of the samples indicated no detectable SiH, OH, or SiOH groups. Neither an afterglow chemistry nor He dilution was required to eliminate H impurities as was previously reported for silicon oxide films deposited from rf plasmas. This suggests that significant differences exist between rf and ECR microwave plasma chemistries. We have found that the stoichiometry and index of refraction was not sensitive to oxidant ratio for a wide range of conditions in contrast to other studies. Stoichiometric SiO2 films, with good physical properties, were grown for a much wider range of oxidant ratios relative to those which are characteristic of the rf PECVD technique. In addition, films grown under optimal conditions had infrared absorption spectra nearly identical to those of thermally grown oxides and index of refraction of 1.456, as measured by ellipsometry. We concluded that by using an ECR microwave plasma, SiO2 films with optical and bonding properties comparable to oxides thermally grown at 1000 °C in dry oxygen can be deposited at a low temperature (350 °C) and a low pressure (10−3 Torr) in a O2/SiH4 reactant gas mixture without the need for a carrier gas.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 64 (1988), S. 4398-4403 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The behavior of electron-cyclotron resonant (ECR) and non-ECR H2 plasmas generated in a microwave plasma chemical-vapor deposition reactor have been studied as a function of magnetic field strength and absorbed microwave power. Plasma diagnostics were performed with a planar electrostatic probe, microwave power measurements, and visual inspection. The probe measurements were concerned with the plasma impingent on a sample table placed downstream from the active core of the plasma. ECR plasmas were found to be more efficient, stable, uniform, and dense than plasmas not generated by ECR. All properties of the ECR plasmas measured by the downstream probe showed a gentle monotonic increase with the magnetic field strength. This was attributed to a reduction in the spacing between the probe and the resonant zone. In the ECR plasmas the average electron temperature was 3 eV and the average density was 1016 m−3. The degree of ionization was on the order of 5×10−4.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...