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71.
S. K. Chen A. Serquis G. Serrano K. A. Yates M. G. Blamire D. Guthrie J. Cooper H. Wang S. Margadonna J. L. MacManus‐Driscoll 《Advanced functional materials》2008,18(1):113-120
By applying a combination of characterisation tools, changes in structural and superconducting properties with nominal Mg non‐stoichiometry in MgxB2 are found. The non‐stoichiometry produces enhanced in‐field critical current densities (Jc's) and upper critical field / irreversibility field (Hc2/Hirr(T)) values. Upper critical fields of ~ 21 T (4.2 K) were obtained in nominal Mg‐deficient samples compared to ~ 17 T (4.2 K) for near‐stoichiometric samples. 相似文献
72.
73.
Jean‐Marc Aldric Philippe Thonart 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(10):1401-1408
BACKGROUND: In the framework of biological processes used for waste gas treatment, the impact of the inoculum size on the start‐up performance needs to be better evaluated. Moreover, only a few studies have investigated the behaviour of elimination capacity and biomass viability in a two‐phase partitioning bioreactor (TPPB) used for waste gas treatment. Lastly, the impact of ethanol as a co‐substrate remains misunderstood. RESULTS: Firstly, no benefit of inoculation with a high cellular density (>1.5 g L?1) was observed in terms of start‐up performance. Secondly, the TPPB was monitored for 38 days to characterise its behaviour under several operational conditions. The removal efficiency remained above 63% for an inlet concentration of 7 g isopropylbenzene (IPB) m?3 and at some time points reached 92% during an intermittent loading phase (10 h day?1), corresponding to a mean elimination capacity of 4 × 10?3 g L?1 min?1 (240 g m?3 h?1) for a mean IPB inlet load of 6.19 × 10?3 g L?1 min?1 (390 g m?3 h?1). Under continuous IPB loading, the performance of the TPPB declined, but the period of biomass acclimatisation to this operational condition was shorter than 5 days. The biomass grew to approximately 10 g L?1 but the cellular viability changed greatly during the experiment, suggesting an endorespiration phenomenon in the bioreactor. It was also shown that simultaneous degradation of IPB and ethanol occurred, suggesting that ethanol improves the biodegradation process without causing oxygen depletion. CONCLUSION: A water/silicone oil TPPB with ethanol as co‐substrate allowed the removal of a high inlet load of IPB during an experiment lasting 38 days. Copyright © 2008 Society of Chemical Industry 相似文献
74.
Ricardo Beristain‐Cardoso Anne‐Claire Texier Reyes Sierra‐Álvarez Jim A Field Elías Razo‐Flores Jorge Gómez 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(9):1197-1203
BACKGROUND: Simultaneous removal of sulfur, nitrogen and carbon compounds from wastewaters is a commercially important biological process. The objective was to evaluate the influence of the CH3COO?/NO3? molar ratio on the sulfide oxidation process using an inverse fluidized bed reactor (IFBR). RESULTS: Three molar ratios of CH3COO?/NO3? (0.85, 0.72 and 0.62) with a constant S2?/NO3? molar ratio of 0.13 were evaluated. At a CH3COO?/NO3? molar ratio of 0.85, the nitrate, acetate and sulfide removal efficiencies were approximately 100%. The N2 yield (g N2 g?1 NO3?‐N consumed) was 0.81. Acetate was mineralized, resulting in a yield of 0.65 g inorganic‐C g?1 CH3COO?‐C consumed. Sulfide was partially oxidized to S0, and 71% of the S2? consumed was recovered as elemental sulfur by a settler installed in the IFBR. At a CH3COO?/NO3? molar ratio of 0.72, the efficiencies of nitrate, acetate and sulfide consumption were of 100%, with N2 and inorganic‐C yields of 0.84 and 0.69, respectively. The sulfide was recovered as sulfate instead of S0, with a yield of 0.92 g SO42?‐S g?1 S2? consumed. CONCLUSIONS: The CH3COO?/NO3? molar ratio was shown to be an important parameter that can be used to control the fate of sulfide oxidation to either S0 or sulfate. In this study, the potential of denitrification for the simultaneous removal of organic matter, sulfide and nitrate from wastewaters was demonstrated, obtaining CO2, S0 and N2 as the major end products. Copyright © 2008 Society of Chemical Industry 相似文献
75.
天津市水环境污染综合整治思路 总被引:1,自引:0,他引:1
天津市位于海河流域下游.历史上曾得益于海河丰沛的水资源,自进入20世纪70年代以后.由于流域内人口增长、经济发展、用水量增加,致使河流入境水量急剧减少。1983年引滦入津工程建成通水,天津城市缺水的局面暂时得到缓解,但引滦供水能力有限,供水保证率较低,1997~2000年连续干旱,引滦源头潘家口水库蓄水降至死库容以下。为解决天津城市缺水,2000年再次引黄济津。 相似文献
76.
Haijun Fang Zongli Lin 《Automatic Control, IEEE Transactions on》2006,51(7):1177-1184
In this note, we revisit the problem of global practical stabilization for planar linear systems subject to actuator saturation and input additive disturbances. A parameterized linear state feedback law is designed such that, by tuning the value of the parameter, all trajectories of the closed-loop system converge to an arbitrarily small neighborhood of the origin in a finite time and remain in there. 相似文献
77.
H.J. Bolink E. Coronado D. Repetto M. Sessolo E.M. Barea J. Bisquert G. Garcia‐Belmonte J. Prochazka L. Kavan 《Advanced functional materials》2008,18(1):145-150
A new type of bottom‐emission electroluminescent device is described in which a metal oxide is used as the electron‐injecting contact. The preparation of such a device is simple. It consists of the deposition of a thin layer of a metal oxide on top of an indium tin oxide covered glass substrate, followed by the solution processing of the light‐emitting layer and subsequently the deposition of a high‐workfunction (air‐stable) metal anode. This architecture allows for a low‐cost electroluminescent device because no rigorous encapsulation is required. Electroluminescence with a high brightness reaching 5700 cd m–2 is observed at voltages as low as 8 V, demonstrating the potential of this new approach to organic light‐emitting diode (OLED) devices. Unfortunately the device efficiency is rather low because of the high current density flowing through the device. We show that the device only operates after the insertion of an additional hole‐injection layer in between the light‐emitting polymer (LEP) and the metal anode. A simple model that explains the experimental results and provides avenues for further optimization of these devices is described. It is based on the idea that the barrier for electron injection is lowered by the formation of a space–charge field over the metal‐oxide–LEP interface due to the build up of holes in the LEP layer close to this interface. 相似文献
78.
Shu‐Li Sun Jing Ma Nan Lv 《International Journal of Adaptive Control and Signal Processing》2008,22(10):932-948
Based on the optimal fusion estimation algorithm weighted by scalars in the linear minimum variance sense, a distributed optimal fusion Kalman filter weighted by scalars is presented for discrete‐time stochastic singular systems with multiple sensors and correlated noises. A cross‐covariance matrix of filtering errors between any two sensors is derived. When the noise statistical information is unknown, a distributed identification approach is presented based on correlation functions and the weighted average method. Further, a distributed self‐tuning fusion filter is given, which includes two stage fusions where the first‐stage fusion is used to identify the noise covariance and the second‐stage fusion is used to obtain the fusion state filter. A simulation verifies the effectiveness of the proposed algorithm. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
79.
涤纶复合丝(POY+DTY)的研发 总被引:1,自引:0,他引:1
DTY和POY网络复合丝是以聚酯直纺生产的两种不同规格的POY丝为原料,通过对加弹机进行适当改造,利用不同的加工路线,使一股POY丝经过加捻后形成DTY,再与另一股POY丝网络合股形成包芯复合丝.该复合丝利用POY丝和DTY丝的收缩差异和染色差异等不同风格特性,使得布面形成一种具有雪花状的色丁效果.该复合丝属于差别化纤维,是国家鼓励发展的项目,它具有优良的吸湿排汗性能和弹性保暖性能,是保暖内衣的首选面料,市场前景广阔. 相似文献
80.
Lie‐Fern Hsu 《Quality and Reliability Engineering International》2007,23(2):269-272
He and Grigoryan (Quality and Reliability Engineering International 2002; 18 :343–355) formulated the design of a double‐sampling (DS) s control chart as an optimization problem and solved it with a genetic algorithm. They concluded that the DS s control charts can be a more economically preferable alternative in detecting small shifts than traditional s control charts. We explain that, since they only considered the average sample size when the process is in control, their conclusion is questionable. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献