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991.
    
Ohne Zusammenfassung  相似文献   
992.
Lactose is used in the pharmaceutical industry for tabletting. For this purpose it must be purified to pharmaceutical grade. Many of the properties of crystallized lactose make it suitable for tabletting, but further research is needed into the mechanisms involved in the prom. Lactose can also be used as a basis for the production of lactulose lactitol and lactobionic acid. These processes are described, and possible commercial applications for the products are discussed.  相似文献   
993.
994.
The decision on technologies used for reclaiming wastewater appears as important as a consequence of the implications on the economic, environmental and health conditions of societies. The problem arises when deciding how to deal with wastewater in small communities, because the costs of implementing and operating small, intensive wastewater treatment plants are unacceptable and can lead to financing and operation problems. Extensive treatment systems can be a good solution, where space is available. This paper presents the combination of two soft technologies (infiltration-percolation and constructed wetlands) to treat and reclaim wastewater. The obtained results show that the infiltration-percolation effluent presents a quality enough to be reused for irrigation of industrial crops, nurseries, fodder, cereals and oleaginous seeds, ornamental flower production; industrial cooling; impoundments, water bodies, and streams for recreational use in which the public's contact with the water is not permitted; and irrigation of forested areas, landscape areas and restricted access areas. Moreover, the combination of infiltration-percolation and constructed wetlands increases the list of final reclamation to the following: irrigation of pasture for milk or meat animals, crops for canning industry, crops not raw-consumed, fruit trees except by sprinkling, aquaculture; and aquifer recharge by localised percolation through the soil.  相似文献   
995.
996.
This brief presents an application-specific instruction-set processor (ASIP) for real-time Retinex image and video filtering. Design optimizations are addressed at algorithmic and architectural levels, the latter including a dedicated memory structure, an adapted pipeline, bypasses, a custom address generator and special looping structures. Synthesized in CMOS technology, the ASIP stands for its better energy-flexibility tradeoff versus reference ASIC and digital signal processing Retinex implementations.  相似文献   
997.
Up to 30% of the released colour arising from bleached kraft pulp and paper production comes from the alkaline extraction stage. This waste stream can therefore be readily targeted to remove colour at source in mills where improved colour management is required. The efficacy of five advanced oxidative treatment and physico-chemical technologies in removing colour from a typical Eop stage effluent was compared. The most effective oxidative treatment was peroxymonosulphate (79% colour removal in 15 minutes). Ozone and TAML treatments removed 74% and 58% of colour respectively within 30 minutes. In comparison, hydrogen peroxide alone was only able to remove 35% of the colour over 4 hours. Coagulation with polyaluminium chloride achieved 89% colour removal within 5 minutes. However, this treatment produced an undesirable sludge, and may cause toxicity in the treated wastewater. Overall, colour removal ability of the five technologies ranked from highest to lowest was polyaluminium chloride > peroxymonosulfate > ozone > TAML > hydrogen peroxide. Other factors, such as operating costs, feedstock modification and capital infrastructure, also need to be taken into account when selecting the most suitable colour management option.  相似文献   
998.
A rapid procedure for the isolation and clean-up on a silica gel column is described for the determination of Ochratoxin A from pork kidneys. The detection limit is 0.3 microgram/kg.  相似文献   
999.
Accurate assessment of the availability of solar energy at the Earth's surface is hampered by difficulties associated with the variability of solar radiation in space and time and with the angular position in the sky hemisphere. This paper assesses each of these problem areas by highlighting the difficulties and the attempts to offset them. Major emphasis is placed on extrapolation and interpolation procedures, the sensitivity of inclined surfaces to variations in the solar input, numerical models for calculating the irradiance of inclined surfaces and the time scales for which these computations are valid.Finally, the reader is urged to consider the significance of these difficulties in light of both radiation measurement errors and the sensitivity of the application to imprecise determinations of the radiation environment.  相似文献   
1000.
Zusammenfassung Generell stellen die Verbindungsbereiche Schwachstellen dar. Zwar k?nnen in gewissen F?llen derartige Schwachstellen umgangen werden. im Vordergrund steht jedoch eine gesicherte Erh?hung der Leistung bekannter Verbindungsarten. Voraussetzung hierfür sind auf die jeweilige Verbindung (und Holzart) ausgerichtete konstruktive L?sungen. H?ufig lassen sich derartige Entwicklungen nicht oder nur unvollst?ndig durch bereits normierte Regeln der Baukunde abdecken. In general jointed areas are considered weak links. Although in certain cases these weak areas may be circumvented, it is important to make efforts towards improving the performance of established joints. Constructive solutions adapted to specific joints (and wood species) are one of the preconditions towards this am. Frequently this kind of development is merely insufficiently or not at all covered by existing standardized regulations in construction technology.
High performance jointing techniques—State of art and development

Nach einem Vortrag des Verfassers auf der Dreil?nder-Holztagung 1984 in Augsburg  相似文献   
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