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71.
In this paper experiments are described in a bio-disc pilot plant. A new method has been developed for a reproducible measurement of the thickness of the waterfilm on the rotating discs. The results were used to calculate the oxygen transfer coefficient into water (KL). The values of KL, calculated in this way, appeared to be considerably higher than experimental KL-values, which is mainly due to the fact that the water layer on the rotating disc is outdistanced by the disc. This effect has not been taken into account in the literature so far. 相似文献
72.
A short-term study of a commercially-available physical—chemical waste treatment plant is reported. Results indicate that an excellent quality of effluent can be consistently obtained despite wide fluctuations of influent wastewater characteristics. Physical, chemical, and biological parameters were monitored. The short-term data obtained offer some evidence of superior treatment efficiency in terms of COD, color, turbidity, and phosphorus removals when compared to more conventional treatment methods. 相似文献
73.
焦五一 《建筑科学与工程学报》1989,(2)
本文用弦线模量计算了营业楼地基的压缩变形和湿陷变形,以及由它们引起的差异沉降值和局部倾斜。计算结果和楼房的裂缝情况吻合。计算湿陷变形时考虑地基浸水后的含水量为30.00%,这是由实测情况确定。根据浸水的实际状况计算建筑物的湿陷变形,分析工程事故在文献中似未见到。 相似文献
74.
Munschy C Héas-Moisan K Tixier C Boulesteix L Morin J 《The Science of the total environment》2011,409(21):4618-4627
Brominated flame retardants (BFRs) were investigated in juvenile common sole from nursery zones situated along the French coast in 2007, 2008 and 2009. Extensive identification was performed with regard to PBDEs, novel BFRs 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) and decabromodiphenylethane (DBDPE), and other non-PBDE BFRs, namely, hexabromobenzene (HBB) and 2,2′,4,4′,5,5′-hexabromobiphenyl (BB-153). Polybrominated diphenyl ether (PBDE) concentrations (Σ 14 congeners) ranged from 0.01 ng/g to 0.16 ng/g wet weight (ww) in muscle, and 0.07 ng/g to 2.8 ng/g ww in liver. Concentrations were in the lower range of those reported in the literature in other European locations. Lower PBDE concentrations, condition indices and lipid contents were observed in the Seine estuary in 2009, possibly in relation to a lower water flow. The PBDE patterns and ratios we observed suggested that juvenile sole have a relative high metabolic degradation capacity. Non-PBDE BFRs were detected at lower levels than PBDEs, i.e., within the < method detection limit - 0.005 ng/g ww range in muscle, and < method detection limit - 0.2 ng/g ww range in liver. The data obtained is of particular interest for the future monitoring of these compounds in the environment. 相似文献
75.
The introduction of ionic additives, such as KCN, or acidic comonomer units, such as methacrylic acid, which change the nature of the mechanism of nitrile oligomerization reaction from radical to ionic and cause its initiation at lower temperature, allows the level of obscurity and the total amount of smoke production, both in smouldering and flaming conditions to be decreased. An opposite result is obtained if diphenylpicrylhydrayl (DPPH) radicals in polyacrylonitrile is introduced; DPPH retards the initiation of the radical nitrile oligomerization reaction. The acrylonitrile-methacrylic acid copolymers have a limiting oxygen index, which increases with the methacrylic acid content. Owing to the increased amount of NH3 produced during pyrolysis, the copolymers have a swelling behavior during the combustion test. 相似文献
76.
Theoretical analyses are presented for the linear free vibration of a clamped-free cylindrical shell partially filled with an incompressible, inviscid liquid. For the vibration of the shell itself, the dynamic version of the Donnell equations was used and the problem was solved with the modified Galerkin procedure, taking the effect of the axisymmetric deformation due to the static liquid pressure into consideration. Concerning the vibration relevant to the liquid motion, the solution for the velocity potential was assumed as a sum of two sets of linear combinations of the suitable harmonic function, the unknown parameters of which were imposed to satisfy both boundary conditions along the wetted shell wall and the free liquid surface in a sense of appropriate series expansions. The procedure stated in the foregoing leads to a determinantal equation for the determination of the natural frequencies of the present shell-liquid system. To compare with the experimental results which will be stated in a companion paper,14 detailed numerical results will be presented in another companion paper13 on the free vibration characteristics of the two test cylinders partially filled with water. 相似文献
77.
Abstract: A generally applicable mathematical model, tailored for use on a Personal Computer, as the design tool to simulate unsteady flood flow in a network of interconnected rivers has been developed and applied to the Sham Chun River along the border between Hong Kong and the People's Republic of China. The effect on the improved Sham Chun River due to the proposed river training in the River Indus, one of its tributaries, is evaluated. The one-dimensional unsteady flow model itself is broadly applicable to a wide range of hydrologic conditions and varying field situations. It incorporates real hydraulic features including branched channels and 'tidal flats' flooding and drying. The time history of water stages and discharges are computed at any desired location throughout the connected essentially one-dimensional channel network subject to initial and boundary conditions. Details are given of techniques adapted in using the computational scheme to quantify the unsteady flow condition and the means to assure an efficient numerical solution as well as to verify the accuracy of the computed outputs by subjection to carefully selected schematic simplified test cases and real prototype cases with numerical solution method is a useful predictive engineering tool in river design. 相似文献
78.
What are the effects of flame behavior of a number of fires burning in close proximity to one another? The results of measurements of burning rates, heat feedback, flame height, and flame trailing are reported for fires involving liquid pools. 相似文献
79.
Conclusions 1. Application of the method of underwater concreting with the use of a container is inexpedient in connection with the presence of a large number of flaws detected in the shafts of cast-in-place piles formed by this method; concreting of holes by the VAT method is preferable.2. The strength of concrete in the shafts of cast-in-place piles increases, reaching a maximum at a depth of 0.4–0.5 the length of the shaft. Variation in strength along the shaft is explained primarily by the percentage of coarse aggregate contained in the concrete.3. The quality of pile concrete should be monitored during all stages of pile installation, and, primarily during the stage of concreting, i.e., when there is a chance of correcting an observed defect.All-Union Institute for the Design and Planning of Health Resorts. Scientific-Research Institute of Foundations and Underground Structures. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 5, pp. 14–17, September–October, 1976. 相似文献
80.
T.J. Shields 《Fire Technology》2003,39(3):275-284
The Institute of Fire Safety Engineering Research and Technology Centre (FireSERT) at the University of Ulster in Northern Ireland has been a major provider of higher technical fire safety education, fire related research and services to industry for over 20 years. Its internationally recognised research spans the fields of fire dynamics, structural fire engineering, human behaviour in fire and more recently fire (CFD) modelling. Since 1991, it has offered the only PG Dip/MSc Fire Safety Engineering programme in the United Kingdom. In September 2000 FireSERT was the recipient of a £5.7 m Joint Infrastructure Fund (JIF) Award to build new fire safety engineering laboratories on the University's Jordanstown campus. These new facilities unparallel in the University sector in the UK offer greater scope and depth to the FireSERT's research portfolios. The new facilities will be extensively used in support of FireSERT's suite of MSc Fire Safety Engineering and DPhil programmes. This paper presents a brief history of FireSERT and its achievements, together with an update on the new facility, current research themes, taught programmes, research opportunities and visions for the future. 相似文献