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排序方式: 共有10000条查询结果,搜索用时 546 毫秒
61.
S H Lee J H Ko J R Kim Y J Kim J J Lee C W Kim T H Lee 《Water science and technology》2006,53(4-5):115-123
The adverse effect of nitrate on the phosphate release rate in the anaerobic phase was observed and was hardly explainable with conventional EBPR process models. Four possible mechanisms were proposed including substrate competition, reduced fermentation, parallel reaction and sequential reaction. Batch experiments were designed and conducted to identify the dominant mechanism. Results showed that the sequential reaction was the only possible mechanism where only denitrification occurred if any nitrate existed in the anaerobic phase. Then the phosphate release following after the nitrate was completely removed. Nitrate inhibition effect was added into the PHA storage rate to incorporate the sequential reaction in the conventional ASM3 plus EAWAG bio-P module (ASM3 + P). Nitrate inhibition coefficient, K(I,NO,PAO) was found to be as low as 0.05 mg/L. This correlated well with experimental observation where no also meant that the anaerobic compartment of a continuous flow reactor could be seriously affected by the residual nitrate contained in the sludge recycle flow. This phenomenon caused overestimation of the phosphate uptake rate and consequently underestimation of PO4(3-) -P concentration. This problem was resolved by incorporation of a nitrate inhibition term in the ASM3 + P for more accurate simulation of the EBPR process. 相似文献
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63.
Marketing online banking services: The voice of the customer 总被引:1,自引:1,他引:0
US banks have invested heavily in developing online capabilities, with the expectation of migrating customers to the new cheaper delivery system. Results in the USA thus far have been mixed at best; market penetration is low and customer usage is sporadic, focusing mainly on simple tasks. This paper reports on the first of two studies conducted to investigate the reasons for the mediocre performance. A qualitative consumer study revealed significant differences in attitudes and opinions between early users and those that banks hope will adopt next. Most importantly, future prospects could be characterised as indifferent about online banking; many were not convinced about its benefits and the value it provides. While the potential to expand the market for online banking services exists, banks need to re-examine their marketing approach. 相似文献
64.
Differences between bank employees' perceptions towards implications of electronic banking in Greece
Konstantinos Lymberopoulos Ioannis E Chaniotakis 《Journal of Financial Services Marketing》2003,8(1):35-47
This paper aims to identify both the Greek branch and the central division employees' perceptions towards implications of electronic banking adoption and explore whether there are any differences between them. To this end, based on 14 potential implications recognised in the literature review, a questionnaire was designed and completed by 613 bank employees. The analysis showed that perceptions vary in relation to respondents' working position. Additionally, there are indications that the identified differences are greater if they are linked with the respondents' working experience and educational qualifications, as well as the size of the financial institution. In conclusion, the paper discusses the strategic implications of the findings. 相似文献
65.
Up until today extreme rainfall properties are frequently applied in sewer design guidelines. Uncertainty in the estimation of such properties will hence directly influence the dimensions of sewers, structures and pumps. In this paper the issue of potential trend and noise in the estimation is investigated for 6 rain series ranging from 19 to 55 years in duration. Different to recent research that predicts a climate induced-increase in heavy precipitation no clear indication for such trend was found in the investigated historical rain series. Another important aspect is the length of the rain series that is required for the estimation of extreme rainfall properties and the associated uncertainty. The analysis indicates that at least a period of 10 years should be used for the estimation. But even so the possible deviation expressed in terms of the 90 percentile is in the order of 5 to 10% of the 'true value', defined as the value derived when the whole given series is used for the estimation. 相似文献
66.
The objective of this study was to compare methane production and characteristics of digested material in anaerobic digestion concepts according to the Animal By-Products Regulation (ABP-Regulation) of the EC (hygienisation of biowaste for 1 hour at 70 degrees C, particle size < 12 mm) and Finnish national regulations (treatment temperature 55 degrees C, feeding interval 24 h, hydraulic retention time (HRT) 20 d, particle size < 40 mm) and with small variations in treatment methods for treating manure and biowaste. Moreover, the survival of three different salmonella bacteria in these processes was studied. Hygienisation of biowaste prior to digestion at 35 degrees C enhanced methane production by 14-18% compared to similar treatment without hygienisation. The differences in treatment temperature, HRT and hygienisation of biowaste prior to digestion did not significantly affect the characteristics of digested material. The concepts according to the ABP-Regulation and Finnish national regulations were effective in destroying salmonella bacteria to an undetectable level. 相似文献
67.
Y Terashima H Ozaki R R Giri T Tano S Nakatsuji R Takanami S Taniguchi 《Water science and technology》2006,54(8):55-63
Environmental pollution by low concentrations of 2,4-Dichlorophenoxyacetic acid (2,4-D) is a concern these days due to ever increasingly stringent regulations. Photocatalysis with immobilized TiO2 fiber is a promising oxidation method. Laboratory experiments on photocatalytic degradation of 0.045 mmol l(-1) 2,4-D with the world's first high-strength TiO2 fiber catalyst were carried out in a continuous flow reactor in which the degradations were, in general, similar to those with high 2,4-D concentrations investigated elsewhere. Degradation and mineralization of 2,4-D were significantly enhanced with no initial pH adjustments. The rate constants for total organic carbon (TOC) without pH adjustment were about two-fold bigger than the pH adjustment cases. CO2 gas measurement and carbon mass-balance were carried out for the first time, where about 34% organic carbon converted into CO2 gas during four-hour oxidation. 2,4-Dichlorophenol (2,4-DCP), phenol, benzyl alcohol and two unknowns (RT = 2.65 and 3.78 min.) were detected as aromatic intermediates while Phenol was the new aromatic in HPLC analysis. Dechlorination efficiencies were high (> 70%) in all the cases, and more than 90% efficiencies were observed in chloride mass balance. Bigger flow rates and solution temperature fixed at 20 degrees C without pH adjustment greatly enhanced 2,4-D mineralization. These results can be an important basis in applying the treatment method for dioxin-contaminated water and wastewater. 相似文献
68.
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70.
Jay Ginn 《Journal of Financial Services Marketing》2003,7(4):319-329
Present policy means that a private pension, unless it is substantial, may fail to bring financial gain in retirement due to means testing: the pensions poverty trap. This paper examines women's acquisition of private (occupational and personal) pensions and their risk of facing this trap. Because of the loosening link between marriage and motherhood, previous patterns of pension advantage according to marital status are shifting. The employment and pension impact of motherhood varies with socio-economic status but the pension prospects of the majority of women are poor. It is concluded that women's need for financial advice to avoid the pensions poverty trap is greater than men's. An improved basic pension, indexed to national income, would reduce the risk of mis-selling and restore confidence that saving for a pension is worthwhile. 相似文献