RESEARCH ON FAULT DIAGNOSIS OF WIND TURBINE PLANETARY GEARBOX UNDER VARIABLE SPEED

Due to the nonstationarity, complex transmission path, high system noise and serious modulation phenomenon of wind turbine gearbox vibration signal, the conventional spectrum analysis method was difficult to identify the fault location of gearbox. In order to solve the above problems, a fault diagnosis method of wind turbine planetary gearbox based on synchronous extraction（SET）and vold-Kalman filter（SEV） was proposed in this paper. This paper first describes the principle and process of the proposed method. The vibration signal of the generator bearing was extracted by the local energy maximum method based on SET（LMS）, and then the instantaneous frequency was accurately extracted based on the ward Kaman filter to obtain the complete phase information. Finally, the detailed fault location information of wind turbine gearbox was obtained by order analysis. Simulation and experimental analysis verify the effectiveness of the proposed method

The key factor in High Pressure Hydrogenotrophic Denitrification: Hydrogen partial pressure

In the envisaged hydrogen economy, H2 could be an interesting alternative electron donor for the denitrification of drinking water or wastewater. The main obstacle to engineering the hydrogenotrophic denitrification process is the low solubility of H2 in water under atmospheric pressure, which limits denitrification rate and nitrogen removal efficiency. In this paper, we demonstrated a novel configuration of hydrogenotrophic denitrification, namely High Pressure Hydrogenotrophic Denitrification (HPHD). Elevated H2 partial pressure (pH2) was employed to increase dissolved H2 concentration and concomitantly enhance denitrification rate. Our results showed that the specific denitrification rate increased from 9.6 mg N/(gVSS·h) at 0.5 bars to 51.0 mg N/(gVSS·h) at 9 bars in HPHD. The denitrification effect could be retained with elevated pH2 at a low temperature. The specific denitrification rate at 3 bars and 15 °C was 20.5 mg N/(gVSS·h), approximately 1.5 times that at 1 bar and 30 °C, which was quite beneficial for hydrogenotrophic denitrification under cold conditions. Different from nitrite reduction, less impact was observed on nitrate reduction by low temperature, which explained high nitrite accumulation in HPHD at 15 °C. Overall, our investigations shed light on the role of pH2 in the promising solution for nitrogen removal in HPHD.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Sanitary Engineerin

RETRACTED: Population genetic data from 23 autosomal STR loci of Huaxia Platinum system in the Jining Han population

Abstract Background Genetic polymorphisms at 23 short tandem repeat (STR) loci were investigated in 1,215 Jining Han individuals from Jining city, Shandong province, eastern China. Methods We used population genetic data of 23 autosomal STR loci included in the Huaxia Platinum system to evaluate 1,215 unrelated Chinese Han individuals in the Jining Han population. Allele frequencies and forensic parameters of the STR loci were determined and genetic relationships among the Jining Han and other Chinese populations were evaluated. Results In total, we observed 321 alleles, with frequencies ranging from 0.00041 to 0.52222. The combined discrimination power and probability of excluding paternity were 0.99999999999999999999999999919 and 0.99999999962, respectively. No deviations from HWE were observed at any loci. Population comparisons showed that the Xinjiang groups (Uyghur and Kazakh) and the Mongolian and Tibetan groups were isolated, while the Jining Han population clustered together with other populations, except the Guizhou Han population. Conclusion This study demonstrated that 23 autosomal STR loci included in the Huaxia Platinum system are highly polymorphic and suitable for personal forensic identification and paternity testing in this population

Efficient degradation of antibiotics in different water matrices through the photocatalysis of inverse opal K-g-C3N4: Insights into mechanism and assessment of antibacterial activity

The efficient degradation of fluoroquinolone antibiotics and the reduction of their antimicrobial activity were achieved in different water matrices through the photocatalysis of inverse opal potassium-doped carbon nitride (IO K-CN). The IO K-CN photocatalyst with optimum doping ratio of potassium performed much better than bulk carbon nitride and pure inverse opal carbon nitride for removing fluoroquinolone antibiotics, such as levofloxacin (LVX) and norfloxacin (NOR). The remarkably narrowed band gap resulting from potassium doping and the unique properties of the inverse opal construction jointly contributed to enhancing the activity of the photocatalyst. A possible mechanism and degradation pathway for LVX was proposed on the basis of a series of characterizations including electron spin resonance (ESR) experiments, and liquid chromatography-mass spectrometry (LC-MS) analysis. Meanwhile, the byproducts during the LVX photocatalytic degradation were shown to have much lower sterilization effect, implying that the toxicity and the potential risk of LVX were excellently reduced. The potential application for the treatment of antibiotic-containing wastewater was indicated by the excellent treatment efficiency and favorable durability of this photocatalyst. © 2020 Elsevier B.V.1

Data_Sheet_1_Purification and Initial Characterization of 3-Hydroxybenzoate 6-Hydroxylase From a Halophilic Martelella Strain AD-3.docx

<p>3-Hydroxybenzoate 6-hydroxylase, an NADH-dependent flavoprotein, can convert 3-hydroxybenzoate which is an important intermediate in the biodegradation of many aromatic hydrocarbons. 3-Hydroxybenzoate is metabolized by entering the TCA cycle through the gentisate pathway. We found a putative 3HB6H gene from a cluster that potentially encodes for gentisic acid degradation from a halophilic Martelella sp. strain AD-3. The corresponding protein was expressed with an N-terminal His-tag and purified by Ni²⁺-nitrilotriacetic acid affinity chromatography. The protein showed an overexpressed band of about 46 kDa by SDS–PAGE, and it was also proven that the enzyme contains FAD by absorption spectroscopy and HPLC analysis. The optimal activity of 3HB6H from strain AD-3 was observed in phosphate buffer (pH 8.0) at 37°C without salinity (NaCl) and metal salts. The K_m values of 3-hydroxybenzoate 6-hydroxylase were determined to be 72.6 ± 10.1 μM and 104.1 ± 18.2 μM for 400 μM NADH and 3-hydroxybenzoate, respectively. Site-directed mutagenesis showed that residues 305, 306 and 308 are important for FAD binding. In addition, we found that Tyr221 and Gln305 of 3HB6H from strain AD-3 are involved in substrate binding.</p