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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   
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This letter presents a novel approach for organizing computational resources into groups within H.264/AVC motion estimation architectures, leading to reductions of up to 75% in the equivalent gate count with respect to state‐of‐the‐art designs.  相似文献   
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Laparoscopic pelvic lymph node dissection has been applied as a minimally invasive staging technique for men with prostate cancer. This procedure has been shown to shorten markedly postoperative hospitalization, decrease analgesic requirements and shorten convalescence period compared to open pelvic node dissection. However, the laparoscopic procedure takes longer to perform and many disposable instruments are used, thus increasing the cost. We determine the overall cost of laparoscopic versus open pelvic lymph node dissection. Between January 1989 and April 1992, 61 men underwent only staging pelvic lymph node dissection for cancer of the prostate at a single university teaching hospital. Of these patients 11 and 50 underwent open and laparoscopic pelvic lymph node dissection, respectively. Information from the hospital business office was reorganized into preoperative, intraoperative and postoperative expenses. All individual charges were transformed up or down to the dollar amounts of the 1990 to 1991 fiscal year so as to correct for inflationary changes. Preoperative costs were not significantly different between the 2 operative approaches. Intraoperative expenses were 52% greater if laparoscopic pelvic lymph node dissection was performed and can be explained by the longer operative times and use of disposable instrumentation. However, the postoperative period lasted an average of 1.61 days following laparoscopic pelvic lymph node dissection. Postoperative nursing and analgesic requirements were significantly more for patients undergoing open pelvic lymph node dissection. The overall postoperative costs following open pelvic lymph node dissection were 280% more expensive than for the laparoscopic procedure. The overall total costs were approximately $1,250 more for laparoscopic pelvic lymph node dissection. Wages lost or earned during this period and rapid return to normal activity following laparoscopic pelvic lymph node dissection would, in our opinion, justify this additional cost.  相似文献   
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X-ray diffraction and ab initio MO theoretical calculations were used in order to investigate the structural and electronic properties of sarmazenil, a weak inverse agonist at the omega modulatory sites (benzodiazepine receptors). This compound was compared to bretazenil, a partial agonist, and to the antagonist flumazenil on the basis of structural and electronic data. The conformational and theoretical properties (interatomic pi overlap populations, molecular electrostatic potential (MEP), the topology of frontier orbitals, and proton affinity) of these three imidazobenzodiazepinones were determined in order to analyse the stereoelectronic properties in relation with their distinct intrinsic efficacies at the omega modulatory sites.  相似文献   
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单层球面网壳地震反应特征分析   总被引:29,自引:0,他引:29  
考虑不同矢跨比、荷载、跨度和支座刚度等多种因素的影响,对单层球面网壳在地震作用下的反应进行了较全面的研究,给出了其随各参数变化的规律,得出了在单层球面网壳抗震设计中起控制作用的是水平地震作用而不是竖向地震作用等有益的结论.此外本文还给出了由于阻尼比不同而需对引用现行抗震规范反应谱分析的网壳地震作用进行修正的建议.  相似文献   
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We report a 20-year-old man affected by glycogenosis type III with distal muscle weakness, more severe in distal leg muscles. The electromyogram showed myopathic features. Nerve conduction studies and central motor conduction after magnetic stimulation of the brain were normal. Our results suggest that there is no involvement of central motor pathways in this disease.  相似文献   
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Chicken acidic leucine-rich EGF-like domain containing brain protein (CALEB) was identified by combining binding assays with immunological screens in the chicken nervous system as a novel member of the EGF family of differentiation factors. cDNA cloning indicates that CALEB is a multidomain protein that consists of an NH2-terminal glycosylation region, a leucine-proline-rich segment, an acidic box, a single EGF-like domain, a transmembrane, and a short cytoplasmic stretch. In the developing nervous system, CALEB is associated with glial and neuronal surfaces. CALEB is composed of a 140/130-kD doublet, an 80-kD band, and a chondroitinsulfate-containing 200-kD component. The latter two components are expressed in the embryonic nervous system and are downregulated in the adult nervous system. CALEB binds to the extracellular matrix glycoproteins tenascin-C and -R. In vitro antibody perturbation experiments reveal a participation of CALEB in neurite formation in a permissive environment.  相似文献   
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