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11.
p-Nitrophenol removal by combination of powdered activated carbon adsorption and ultrafiltration - comparison of different operational modes 总被引:1,自引:0,他引:1
Ultrafiltration is classified as a low-pressure membrane technology which effectively removes particulate matter and microorganisms and to a certain extent dissolved organic matter (15-25%) and colour. The technology has been optimized and is becoming competitive compared to conventional processes for larger scale plant capacities. In combination with activated carbon it is an effective barrier regarding the removal of synthetic organic chemicals. Growing interest in ultrafiltration raises the question of better usage of the adsorption capacity of powdered activated carbon (PAC) used in combination with this low-pressure membrane technique. This paper presents a pilot plant study of different PAC dosing procedures within a combined hybrid membrane IN/OUT process for removal of p-nitrophenol (PNP) from water (c(0)=1mg/L) under real case conditions (e.g. usage of the same module for the whole duration of the experiment, backwashing with permeate water, no separate saturation of the membrane with substance without presence of carbon). p-Nitrophenol was chosen as an appropriate test substance to assess the efficiency of different operation modes. Dead-end and cross-flow filtration were compared with respect to different PAC dosing procedures: continuous dosing into a continuously stirred tank reactor (CSTR) in front of the module and direct dosing into the pipe in front of the module (continuous, single-pulse and multi-pulse dosing). There was no advantage in cross-flow mode over dead-end referring to PNP concentration in the permeate. Relating to the carbon dosing procedure, the best results were obtained for continuous PAC addition. The option of dosing directly into the pipe has the advantage of no additional tank being necessary. In the case of single-pulse dosing, the formation of a carbon layer on the membrane surface was assumed and an LDF model applied for a simplified estimation of the "breakthrough behaviour" in the thus formed "PAC filter layer". 相似文献
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Hammoud Issa Bauer Nikolas Kallfass Ingmar Kennel Ralph 《Electrical Engineering (Archiv fur Elektrotechnik)》2019,101(3):685-697
Electrical Engineering - In this paper, a comprehensive investigation of the capacitive active ripple compensation (ARC) techniques is made to conclude which one is optimal to be used in on-board... 相似文献
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Computational Visual Media - We consider a face-to-face videoconferencing system that uses a Kinect camera at each end of the link for 3D modeling and an ordinary 2D display for output. The Kinect... 相似文献
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Andrea Linkmeyer Katharina Hofer Michael Rychlik Markus Herz Hans Hausladen Ralph Hückelhoven 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(3):489-499
Fusarium head blight (FHB) of small cereals is a disease of global importance with regard to economic losses and mycotoxin contamination harmful to human and animal health. In Germany, FHB is predominantly associated with wheat and F. graminearum is recognised as the major causal agent of the disease, but little is known about FHB of barley. Monitoring of the natural occurrence of FHB on Bavarian barley revealed differences for individual Fusarium spp. in incidence and severity of grain infection between years and between spring and winter barley. Parallel measurement of fungal DNA content in grain and mycotoxin content suggested the importance of F. graminearum in winter barley and of F. langsethiae in spring barley for FHB. The infection success of these two species was associated with certain weather conditions and barley flowering time. Inoculation experiments in the field revealed different effects of five Fusarium spp. on symptom formation, grain yield and mycotoxin production. A significant association between fungal infection of grain and mycotoxin content was observed following natural or artificial infection with the type B trichothecene producer F. culmorum, but not with the type A trichothecene-producing species F. langsethiae and F. sporotrichioides. Trichothecene type A toxin contamination also occurred in the absence of significant damage to grain and did not necessarily promote fungal colonisation. 相似文献
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Color constancy from invariant wavelength ratios: An algorithm to simplify the chromatic adaptation model 下载免费PDF全文
Ralph W. Pridmore 《Color research and application》2016,41(5):468-476
In a recent article on color constancy, the chromatic adaptation model was of a novel type comprising three components separately calculated—hue, chromaticness, and lightness. The constant hue component was a simple calculation of predicted wavelength but the other two components were less direct. This article provides an algorithm to simplify the model's calculation. Calculation is far simpler and more intuitive than conventional models using complex 3 × 3 matrix transforms with their various and contentious adaptation primaries and potential disadvantages (e.g., in brightness and color gamut). The model is shown to be at least as accurate as six other (conventional) models and does not require high math skill. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 468–476, 2016 相似文献
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The unceasing growth and divergence of the mobile landscape have led to the use of smartphone and tablet devices in consuming Web services (WS) in enterprises. However, in heterogeneous WS, the shift from the mobile client consumer approach to the mobile service hosting approach is insufficiently studied. With the advancement of storage and processing capabilities of these devices, coupled with the high availability of the Web, this research focuses on the use of the mobile devices as hosts of WS in a mHealth domain. In this paper, a cloud-centric middleware technique is employed to enable access to the mobile hosts. The paper presents mobile hosting of medical data which are modeled as light-weight WS which is deployed in a real-world system. Further, a workflow authorization model is proposed to ensure privacy and the prevention of unauthorized modification of data on the mobile hosts. A data encryption technique is also put forward to enforce security and privacy of the mobile hosted data. Our current implemented project, called SOPHRA, supports mobile communication over HTTP in a Wi-Fi environment. 相似文献
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This bibliometric study on the collaboration of Austria and six target countries (Slovenia, Hungary, Czech Republic, Denmark,
Switzerland and Israel) reveals the importance of differentiation between the bilateral and multilateral contingents in the
assessment of international scientific collaboration. For this purpose a “degree of bilaterality” (DB) and a “citation degree
of bilaterality” (CDB) are introduced. In our findings the DB and the CDB have values lower than 1/3 and 1/5, respectively.
Therefore, the total collaboration is mostly shaped in its volume and impact by the multilateral contingent. Regarding the
impact estimation of the collaboration publication output, a multi-faceted approach was used. It is recommended to separately
analyze the following three aspects: the un-cited range, the average range and the excellence range. Considering different
country specific parameters the total number of publications and citations were resized for each type of collaboration and
the results discussed. Only a very weak correlation between ‘times cited’ and the number of affiliations or authors was observed
at publication level. Neither the number of authors or affiliations determines impact increase. Rather internationalisation
and cooperation seem to be the crucial factors. 相似文献