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21.
To take full advantage of computer monitoring and control systems already in existence in many breweries, there is a need for reliable and inexpensive on-line sensors. Prior to the development of any system for production scale conditions, the underlying principles of the method of measurement adopted have to be investigated. Work at the laboratory (1.5 Litre and 11 Litre), pilot (30 Litre) and experimental brewery (100 hl) scales of fermentation has demonstrated that a good correlation exists between evolved CO2 and changes in specific gravity. During the period from the onset of CO2 evolution to the end of a fermentation, it was found that evolved CO2 yield was ca. 1.0 gCO2/Litre/degree gravity drop. Metering systems based on evolved CO2 determination are nonintrusive, simple to install and cost effective. 相似文献
22.
Ali Alaeddine Cécile Genevois Laurence Chevalier Kaouther Daoud 《Nanoscale research letters》2011,6(1):1-11
Nanoscaled materials are attractive building blocks for hierarchical assembly of functional nanodevices, which exhibit diverse performances and simultaneous functions. We innovatively fabricated semiconductor nano-probes of tapered ZnS nanowires through melting and solidifying by electro-thermal process; and then, as-prepared nano-probes can manipulate nanomaterials including semiconductor/metal nanowires and nanoparticles through sufficiently electrostatic force to the desired location without structurally and functionally damage. With some advantages of high precision and large domain, we can move and position and interconnect individual nanowires for contracting nanodevices. Interestingly, by the manipulating technique, the nanodevice made of three vertically interconnecting nanowires, i.e., diode, was realized and showed an excellent electrical property. This technique may be useful to fabricate electronic devices based on the nanowires' moving, positioning, and interconnecting and may overcome fundamental limitations of conventional mechanical fabrication. 相似文献
23.
The time course of the extraction of α-acids by liquid carbon dioxide was investigated and it has been established that there are two zones with greatly differing rates of extraction. The rate in the first zone is governed by ‘solubility’ effects, while in the second zone the rate is limited by ‘diffusional’ effects. Consequently the rate of extraction in the first zone depends upon the flow rate of liquid carbon dioxide while that in the second zone depends upon the time of extraction. The effects on extraction performance of the depth of the bed of hops and the extent of milling were also explored. 相似文献
24.
Faouzia M. Haddada Dhouha Krichène Hédia Manai Imen Oueslati Douja Daoud Mokhtar Zarrouk 《European Journal of Lipid Science and Technology》2008,110(10):905-913
The characterization of virgin olive oils from six Tunisian cultivars, namely Chétoui, Ain Jarboua, Jarboui, Regregui, Rekhami and Neb Jmel, grown in Nebeur (a region of the Kef) was carried out. These cultivars dominate their natural habitats, but with the exception of the Chétoui cultivar they are only scattered throughout the nation. Several analytical parameters were evaluated; these include quality index, fatty acid composition, chlorophylls, carotenoids, sterols, α‐tocopherol and phenolic compounds. Their relationship with oxidative stability was also tested. The main phenols found were tyrosol, hydroxytyrosol, the dialdehydic form of elenolic acid linked to tyrosol and hydroxytyrosol, oleuropein aglycon and pinoresinol. These phenolic compounds, the colorimetric total phenol content and o‐diphenols showed significant correlations with oxidative stability. Furthermore, most of the analytical parameters of the oils that were determined in this study were greatly influenced by genetic factors (cultivar). 相似文献
25.
Khaled Daqrouq Ibrahim N. Abu-Isbeih Omar Daoud Emad Khalaf 《International Journal of Speech Technology》2010,13(2):101-115
This paper investigates the utilization of wavelet filters via multistage convolution by Reverse Biorthogonal Wavelets (RBW)
in high and low pass band frequency parts of speech signal. Speech signal is decomposed into two pass bands of frequency;
high and low, and then the noise is removed in each band individually in different stages via wavelet filters. This approach
provides better outcomes because it does not cut the speech information, which occurs when utilizing conventional thresholding.
We tested the proposed method via several noise probability distribution functions. Subjective evaluation is engaged in conjunction
with objective evaluation to accomplish optimal investigation method. The method is simple but has surprise high quality results.
The method shows superiority over Donoho and Johnstone thresholding method and Birge-Massart thresholding strategy method. 相似文献
26.
27.
The concept of malignant pyoderma (MP) has created controversy since its origin. The distinction of this disease from pyoderma gangrenosum was based on clinical criteria and response to treatment. Herein we discuss our current ideas on this entity and its possible relationship to Wegener's granulomatosis (WG). Follow-up data from the three original cases of MP are reported, as well as additional clinical and laboratory data from cases subsequently thought to represent MP. Many of these cases have similar clinical features such as facial and periauricular ulceration and occasionally signs or symptoms of WG, including positive titers of antineutrophil cytoplasmic antibodies (with a diffuse cytoplasmic staining pattern) (cANCA). MP represents a distinctive clinical disorder and may be a dermal manifestation of WG. Some cases of MP may represent pyoderma gangrenosum or other undefined systemic illnesses. Such cases of WG can be distinguished on the basis of clinical, histopathologic, and laboratory evidence including cANCA titers. MP should no longer be used as a final clinical diagnosis. 相似文献
28.
29.
The quality of beers bittered with liquid CO2 and ethanol extracts derived from fresh and deteriorated hops and the percentage utilization of alpha-acids therefrom were comparable. The importance of using analytical methods which measure bitterness substances per se is emphasized. 相似文献
30.
Pyoderma gangrenosum (PG) is a rare, poorly understood skin disease that occurs in all age groups. Less than 0.4% of patients are infants and represent a diagnostic challenge as early lesions may resemble other skin disorders. Here we report for the first time three siblings affected with PG all presenting during infancy. Unlike the older age group, the ulcers spared the legs but involved the buttocks, thighs and perianal area in all the infants. Conclusion: This is the first reported family with PG affecting three siblings suggesting autosomal recessive inheritance. The diagnosis may be more difficult in infants due to absence of underlying associated disorders and the tendency of the lesions to appear in areas where infants frequently have other dermatoses. PG characteristically involves the buttocks, thighs and perianal area and spares the legs. 相似文献