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101.
102.
Progesterone and luteinizing hormone (LH) were measuured in the plasma of Large White turkey hens at frequent intervals during the ovulatory cycle and during the periods when ovulations did not occur. The hormones were quantitated at the beginning and the end of the reproductive season to follow the change in patterns and concentrations of these hormones. Radioimmunoassay procedures were used to assay both hormones. Both progesterone and LH reached a peak amount at about 8 to 2 hours before ovulation. At no time did the progesterone peak precede that of LH. On the other hand, the peak of progesterone was observed to last somewhat longer than the LH peak. Progesterone and LH concentrations demonstrated no peak during the non-ovulatory periods. The patterns of both hormones at the end of the reproductive season was about the same as at the beginning of the season, but with lower concentrations.  相似文献   
103.
104.
Studies on cement concrete microstructures are carried out to explain experimentally observed phenomenon and for modeling of concrete at the macroscopic level. In this article, the preparation of polymer impregnated mortar (PIC) is carried out by partially or fully replacing the pores in the cement mortars (OPC) by PMMA. The effect of this polymer impregnation on density and morphology of the cement matrix is studied. The microstructural changes in the mortar, on exposure of these specimens to hydrochloric acid and sea water for 7 and 28 days, are also investigated in this article. The above studies indicated that the polymer addition decreased the voids in the mortar thereby preventing leaching of water soluble salts present in the OPC. It was observed that the polymer also prevented the external chemical media from permeating into the cement matrix and undergoing interactions with it. It is concluded that the durability and chemical resistance properties of the PIC are better compared with OPC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
105.
An efficient strategy for immobilizing proteins on a gold surface was developed by employing the gold binding polypeptide (GBP) as a fusion partner. Using the enhanced green fluorescent protein (EGFP), severe acute respiratory syndrome coronavirus (SARS-CoV) envelope protein (SCVme), and core streptavidin (cSA) of Streptomyces avidinii as model proteins, specific immobilization of the GBP-fusion proteins onto the gold nanoparticles and generation of protein nanopatterns on the bare gold surface were demonstrated. The GBP-fused SCVme bound to gold nanoparticles successfully interacted with its antibody and showed changes in absorbance and color, allowing efficient diagnosis of SARS-CoV. The fusion proteins could be successfully immobilized on the gold surface by nanopatterning and microcontact printing as examined by atomic force microscopy and surface plasmon resonance analysis. The poly(dimethylsiloxane) microfluidic channels were created on the gold surface and were used for antigen-antibody and DNA-DNA interaction studies. Specific immobilization of GBP-EGFP fusion protein and its interaction with the antibody in the microchannels could be demonstrated. By immobilizing the DNA probe through the use of GBP-fused cSA, specific hybridization of the target DNA prepared from Salmonella could also be achieved. The GBP-fusion method allows immobilization of proteins onto the gold surface without surface modification and in bioactive forms suitable for studying protein-protein, DNA-DNA, and other biomolecular interaction studies. Furthermore, these studies can be carried out in a microfluidic system, which allows high-throughput analysis of biomolecular interactions.  相似文献   
106.
This is the first report of the application of silverion impregnated high-performance liquid chromatography (Ag+-HPLC) to the separation of complex mixtures of conjugated linolenic acid (CLA) isomers present in commercial CLA sources and foods and in biological specimens. This method showed a clear separation of CLA isomers into three groups related to their trans,trans, cis,trans or trans,cis, and cis,cis configuration of the conjugated double-bound system. In addition, this method separated within each geometrical isomeric group. Following Ag+-HPLC isolation, gas chromatography (GC)-electron impact mass spectrometry, and GC-direct deposition-Fourier transformed infrared spectroscopy were used to confirm the identity of two major positional isomers in the cis/trans region, i.e., Δ8,10- and Δ11,13-octadecadienoic acid, which had not been chromatographically resolved previously, Furthermore, the potential of this method was demonstrated by showing different Ag+-HPLC profiles exhibiting patterns of isomeric distributions for biological specimens from animals fed a diet containing a commerical CLA preparation, as well as for a commerical cheese product.  相似文献   
107.
The external egg morphology of two stored-product pests, Stegobium paniceum and Lasioderma serricorne, is presented herein based on optical and scanning electron microscope micrographs. The diagnostic characteristics of the eggs of the pests, including the presence or absence of a micropyle, are described and discussed. Overall, several notable differences were observed between the eggs of these species in regard to their shape, size and surface structures.  相似文献   
108.
Übersicht Es wird ein Verfahren zur Berechnung der Verluste von Kreisströmen entwickelt. Es berücksichtigt nicht nur die Verteilung der Streuflüsse von Windungen in der Nut, sondern auch die Verteilung der Streuflüsse von Teilleitern einer Windung. Mittels der Ähnlichkeitstheorie wurden im praktischen Bereich der Frequenzen (einschl. der Frequenzen bei Umrichterspeisung) und der Abmessungen von Zwei- u. Einschichtwicklungen die Gleichungen für die Widerstandsverhältnisse ermittelt.
Additional losses from circulation currents in round conductors of elementary coils
Contents A method for the analysis of losses due to circulation currents was developed. This method takes into consideration not only the distribution of the leakage fluxes from the windings in the slot, but also the distribution of the fluxes from the elementary conductors in the turn. By means of the similarity theory the loss factors of two- and one-layer windings are obtained for frequencies (including frequencies from frequency converters) and sizes in practical ranges.
  相似文献   
109.
In conventional delay‐locked loop circuits, the charge and discharge of the charge pump result in mismatched current reflecting the size of the static phase error. The static phase error between feedback clock and reference clock is likely to be within tens or hundreds of picoseconds (ps). We thus propose an approach using digital calibration methods to reduce the charge pump current mismatch by means of the setup time of the D‐type flip flop. The setup time of D‐type flip flop is determined and duplicated to detect the phase error between the reference clock and feedback clock. It results in a very small static phase error between the reference clock and feedback clock. This paper used a 0.18 µm CMOS process design, with a reference frequency of 700 ~ 900 MHz. The active area is 0.031 mm2, and the phase error after correction is less than 5 ps. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
110.
ZnO films with varying fluorine content were prepared on Corning glass by radio frequency magnetron sputtering of ZnO target containing ZnF2 at room temperature, and the compositional, electrical, optical, and structural properties of the as-grown films together with the vacuum-annealed films were investigated. The fluorine content in the fluorine doped ZnO (FZO) films increased almost linearly with increasing ZnF2 content in sputter target, and the highest atomic concentration was 7.3%. Vacuum-annealing caused a slight reduction of fluorine content in the films. The resistivity of the as-grown FZO films deposited showed a typical valley-like behavior with respect to the fluorine content in film, i.e. having minimum resistivity at intermediate fluorine content. Despite high fluorine content in the FZO films, the carrier concentration remained below 1.2?×?1020 cm?3, leading to very low doping efficiency level. Upon vacuum-annealing, the resistivity of FZO films decreased substantially due to increase in both the carrier concentration and the Hall mobility. From the structural analysis made by X-ray diffraction study, it was shown that addition of small amount of fluorine enhanced the crystallinity of FZO films with (002) preferred orientation, and that large amount of fluorine addition yielded disruption of preferred orientation. It was also shown that doping of fluorine rendered a beneficial effect in reducing the absorption loss of ZnO films in visible range, thereby substantially enhancing the figure of merit.  相似文献   
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