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91.
以模拟生活污水为处理对象,三种不同填料为生物膜载体,运行 A、B、C三个SBBR,通过逐步降温(25、20、15、10、6和5℃)培养驯化处理低温污水的生物膜。运行251周期,三个反应器COD出水浓度均低于50 mg/L;B反应器对氨氮去除效果优于A和C。特别在低温5℃时,A、B和C三个反应器氨氮平均出水浓度分别为14.1、3.79和14.1 mg/L。高通量测序结果显示,5℃时,三个反应器中均以降解有机物的微生物为主;只有B反应器中驯化富集出了嗜冷硝化菌(Candidatus Nitrotoga);而其他有硝化作用的菌属在B反应器中的丰度也高于A和C反应器;不利于脱氮的类固氮菌(Elstera)在A和C反应器中丰度较高。此结果可从微生物角度解释三个反应器处理效果的差异性,表明B反应器处理低温污水有显著优势,其所用填料可结合低温菌进一步开发利用。 相似文献
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为了减小传统的最差情况设计方法引入的电压裕量,提出了一种变化可知的自适应电压缩减(AVS)技术,通过调整电源电压来降低电路功耗.自适应电压缩减技术基于检测关键路径的延时变化,基于此设计了一款预错误原位延时检测电路,可以检测关键路径延时并输出预错误信号,进而控制单元可根据反馈回的预错误信号的个数调整系统电压.本芯片采用SMIC180 nm工艺设计验证,仿真分析表明,采用自适应电压缩减技术后,4个目标验证电路分别节省功耗12.4%,11.3%,10.4%和11.6%. 相似文献
95.
This paper presents a new channel section having semi-cubic parabolic sides and horizontal bottom. The formulae for calculating the area, wetted perimeter are presented. The best hydraulic section is derived using three variables (water depth, water surface width and horizontal bottom width). Results show the ratios of the water surface width to depth, bottom width to depth and water surface width to bottom are all constant for the best hydraulic section. Explicit equations of the best hydraulic section for design are also deduced. Examples show these explicit equations are convenient for design. This type of best hydraulic section is compared with the trapezoid and classic semi-cubic parabolic sections. Results indicate that the area and wetted perimeter are less than those of trapezoid and classic semi-cubic parabolic sections for a given flow discharge. It means less lining and excavation cost is required for construction. 相似文献
96.
为了降低九里山矿综采工作面煤尘质量浓度和瓦斯涌出量,根据九里山矿煤层特性,结合16051工作面的现场实际情况,在充分利用瓦斯抽采钻孔的基础上,探索出回风巷长孔低压渗透注水工艺,结合工作面短孔中压注水工艺,建立中、低压综合注水模式,并进行了分区域对比试验,考察了各区域的煤层含水率、煤尘质量浓度和瓦斯浓度。现场应用效果表明:中、低压综合注水效果较好,煤层含水率提高了2.94倍,煤尘质量浓度降低了80%以上,工作面瓦斯均匀释放,回风巷瓦斯浓度下降了30%以上,达到了较好的注水效果。 相似文献
97.
中低品位磷矿高效清洁综合利用是中国基础磷化工产业发展中遇到的共性瓶颈问题。以中低品位磷矿磷-钙-镁一体化综合利用中试成果为基础,通过创新集成技术对中低品位磷矿直接进行处理,获得高品质磷精矿[w(P2O5)≥36%、w(MgO)≤0.5%]可用于任何湿法磷酸及热法黄磷生产工艺,同时回收高附加值的氢氧化镁和轻质碳酸钙。该工艺磷全部回收、无尾矿产生、实现了废水近零排放,项目的实施对推动中国磷化工产业可持续发展及从源头解决“三磷”问题具有重要意义。 相似文献
98.
Rectangular section control technology(RSCT)was introduced to achieve high-precision profile control during silicon steel rolling.The RSCT principle and method were designed,and the whole RSCT control strategy was developed.Specifically,RSCT included roll contour design,rolling technology optimization,and control strategy development,aiming at both hot strip mills(HSMs)and cold strip mills(CSMs).Firstly,through the high-performance variable crown(HVC)work roll optimization design in the upper-stream stands and the limited shifting technology for schedule-free rolling in the downstream stands of HSMs,a hot strip with a stable crown and limited wedge,local spot,and single wave was obtained,which was suitable for cold rolling.Secondly,an approximately rectangular section was obtained by edge varying contact(EVC)work roll contour design,edge-drop setting control,and closed loop control in the upper-stream stands of CSMs.Moreover,complex-mode flatness control was realized by coordinating multiple shape-control methods in the downstream stands of CSMs.In addition,the RSCT approach was applied in several silicon-steel production plants,where an outstanding performance and remarkable economic benefits were observed. 相似文献
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Bun-Hee Lee Young-Min Park Seung-Hwan Lee Miseon Shim 《International journal of molecular sciences》2015,16(3):6251-6265
Background: Animal and clinical studies have demonstrated that the loudness dependence of auditory evoked potentials (LDAEP) is inversely related to central serotonergic activity, with a high LDAEP reflecting weak serotonergic neurotransmission and vice versa, though the findings in humans have been less consistent. In addition, a high pretreatment LDAEP appears to predict a favorable response to antidepressant treatments that augment the actions of serotonin. The aim of this study was to test whether the baseline LDAEP is correlated with response to long-term maintenance treatment in patients with major depressive disorder (MDD). Methods: Scalp N1, P2 and N1/P2 LDAEP and standardized low resolution brain electromagnetic tomography-localized N1, P2, and N1/P2 LDAEP were evaluated in 41 MDD patients before and after they received antidepressant treatment (escitalopram (n = 32, 10.0 ± 4.0 mg/day), sertraline (n = 7, 78.6 ± 26.7 mg/day), and paroxetine controlled-release formulation (n = 2, 18.8 ± 8.8 mg/day)) for more than 12 weeks. A treatment response was defined as a reduction in the Beck Depression Inventory (BDI) score of >50% between baseline and follow-up. Results: The responders had higher baseline scalp P2 and N1/P2 LDAEP than nonresponders (p = 0.017; p = 0.036). In addition, changes in total BDI score between baseline and follow-up were larger in subjects with a high baseline N1/P2 LDAEP than those with a low baseline N1/P2 LDAEP (p = 0.009). There were significantly more responders in the high-LDAEP group than in the low-LDAEP group (p = 0.041). Conclusions: The findings of this study reveal that a high baseline LDAEP is associated with a clinical response to long-term antidepressant treatment. 相似文献