The effects of main anoxic section oxidation-reduction potential on the metabolism of PHA and TP in continuous-flow single-sludge treatment system

Xiaoling Wang,Hai Lu,Tiehong Song,Ke Zhao 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.3

The experimental results and material balance analysis in this paper revealed the regularity of poly-hydroxy alkanoates (PHA) and total phosphorus (TP) metabolism in a continuous-flow single-sludge wastewater treatment system under different main anoxic section oxidation-reduction potential (ORPan) conditions. We also evaluated the effectiveness of the operation control parameters of ORPan as the continuous-flow single-sludge sewage treatment system from the aspect of the reaction mechanism. Using a programmable logic controller (PLC) automatic control system to take the circulating flow in nitrification as the controlled variable based on the feedback control structure, an experimental study was carried out under the condition of ORPan setting value of 143mV, 123mV, 105mV, 95mV, 72 mV and 57mV, respectively, with other operational design parameters remaining unchanged. Influent water quality of chemical oxygen demand/total nitrogen (COD/TN) was 5.0±0.6. The results showed that when ORPan was set at 95mV, the maximum values of PHA synthesis and storage rate, PHA degradation rate, phosphorus release rate and phosphorus absorption rate in anaerobic and pre-anoxic segments were 82.34, 7.90, 47.31, 14.27, 1.50 and 8.52mg/ (L·h), respectively. According to the metabolic mechanism of PHA and TP, ORPan was further proved to be the operation control parameter of the continuous-flow single-sludge sewage treatment system, and when the COD/TN value was 5.0±0.6, the optimal setting value was 95mV.

Insights into high molecular weight poly(ethylene 2,5-furandicarboxylate) with satisfactory appearance: Roles of in-situ catalysis of metal zinc

Xiaoling Qu,Guangyuan Zhou,Rui Wang,Haiyan Zhang,Zhipeng Wang,Min Jiang,Jun Tang 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.99 No.-

In pursuit of poly(ethylene 2,5-furandicarboxylate) PEF materials with high molecular weight,satisfactory appearance and faster crystallization rate, its preparation from dimethyl furan-2,5-dicarboxylate (DMFD) with ethylene glycol (EG) in the trace presence of metal zinc was performed viatransesterification method. Optimization of the main polymerization parameters enabled Zn-catalyzedPEF to gain high molecular weight (Mn, 5.40 104 g mol 1) and low content of diethylene glycolfurandicarboxylate unit (DEGF, 2.91%). On the basis of experimental phenomena and high performanceliquid chromatography (HPLC), the actual catalytic active species of metal zinc in the polymerization wasspeculated to be a salt of 2, 5-furandicarboxylate derivative (Zn(II)). The in-stiu catalyst can efficaciouslyinhibit the influence of by-product FDCA on the color of PEF, which displayed quite better appearance(close to white). Differential Scanning Calorimetry (DSC) showed that the in-stiu catalytic system acted asnucleating agent (NA) and the crystallization half-time (t1/2) of PEFs-Zn was only 1/4 of that of PEF-tin. Additionally, series of high molecular weight furan-based polyesters from DMFD and diols with differentmethylene (3, 5, 6 and 8) were obtained by zinc powder as in-stiu catalyst, which further evidenced it tobe efficiency and universality.

Hydrothermal Synthesis of CrO2 Nanoparticle Arrays on Ti nano-pit Array Templates

Xiaoling Wang,Lu Wang,Tao Lin,Hailiang Huang,Gehui Wen 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.1

Chromium dioxide (CrO2) nanoparticle arrays were fabricated on Ti nano-pit array templates by hydrothermal synthesis using CrO3 aqueous solution as precursor. The Ti nano-pit array template was obtained by stripping TiO2 nanotube array formed on the Ti foil. CrO2 nanoparticles are arranged in honeycomb pattern in a large area and their surface density reaches 1.5 x 10 10 cm -2. The CrO2 nanoparticle arrays show typical magnetic behavior, and the easy axis is parallel to the plane of Ti nano-pit array template. The influence of the concentration of CrO3 aqueous solution on the CrO2 nanoparticle arrays is studied and the mechanism of the formation of the CrO2 nanoparticle arrays is briefly discussed.

Use of nitrate-nitrogen concentration for controlling source, cellular matter production and oxygen consumption for sewage treatment

Xiaoling Wang,Xiaoyu Zhang,Hai Lu 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.2

Carbon saving, oxygen consumption reduction and cellular matter production reduction of Modified University of Cape Town (MUCT) process under different nitrate-nitrogen concentration in the main anoxic section was studied. This was investigated by material balance analysis, biochemical reaction process and its metrology of ordinary heterotrophic bacteria, denitrifying bacteria, nitrifying bacteria and phosphorus-accumulating bacteria. The flow and distribution of carbon, nitrogen, and oxygen in the MUCT, and the influence of the regulation of the c(NO3) on the carbon source, cellular matter production, and oxygen consumption of the process were explained in detail. In the programmable logic controller (PLC) automatic control system, the circulating flow rate of nitrate was set as the controlled variable. Adopting the feedback control structure, c(NO3) was altered at 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 and 4.0mg·L1, respectively. In this experimental study, the quality of influent and other operation design parameters remained unchanged. The results showed that the effluent quality was at its best when c(NO3) was controlled at 2.0- 4.0mg/L. Again, the distribution of chemical oxygen demand (COD) in the anaerobic section was between phosphorus- accumulating bacteria, common heterotrophic bacteria and denitrifying bacteria, and the distribution was related to c(NO3). Due to this phenomenon, the distribution of nitrate-nitrogen between denitrifying bacteria and denitrifying phosphorus-accumulating bacteria, and poly-hydroxy alkanoates (PHA) between denitrifying phosphorus-accumulating bacteria and aerobic phosphorus-accumulating bacteria was changed. Carbon source of 110.0 kg acetic acid/103m3 sewage was saved, while the cell material output was reduced by 37.5%, and the oxygen consumption of 51.1 kg O2/ 103m3 sewage was reduced. In the MUCT process, the regulation of c(NO3) enhanced the denitrifying phosphorus uptake performance of the main anoxic section and obtained good carbon source savings, reduction of cellular matter production, and reduction of oxygen consumption.

Variation in the quantity and composition of phosphorus accumulating organisms in activated sludge driven by nitrate-nitrogen

Wang Xiaoling,Shi Chunyan,Pan Wenbo,Lu Hai,Zhang Xiaoyu 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.7

Anaerobic/anoxia sequencing batch reactor (A/ASBR) system was used to analyze the quantity and composition of each branch of phosphorus accumulating organisms (PAOs) in activated sludge under different nitrate-nitrogen (NO 3 − -N) concentrations by using real-time quantitative polymerase chain reaction (PCR) technology. The study determined whether NO 3 − -N and its concentration change were the main driving factors for the variation of the quantity and composition of each branch of PAOs. The results show that with the increase of NO 3 − -N concentration from 10 mg/L to 40 mg/L, the number of bacterial 16S rRNA genes in the A/ASBR reactor changed slightly at 6.81×1011–7.53×1011 copies/g dry sludge. The number of PAO genes (Acc 16S rRNA) increased from 1.98×1011 to 3.53×1011 copies/g dry sludge, and the total number of ppk1 genes increased from 1.25×1011 to 3.59×1011 copies/g dry sludge. Additionally, the number of polyphosphate kinase (ppk) genes in Accumulibacter branch IA, IIC and IID was high, and the changes were positively related to the concentration of NO 3 − -N, while the number of branches in IIA, IIB and IIF was very low. The dosing concentration of NO 3 − -N was the main driving factor for the change of PAOs and their branch number and composition in the A/ASBR reactor.

Morphologies and phenotypes in Bacillus subtilis biofilms

Xiaoling Wang,Shuo Meng,Jingshi Han 한국미생물학회 2017 The journal of microbiology Vol.55 No.8

In this study, we explored Bacillus subtilis biofilm growth under various conditions such as the use of substrates with different stiffnesses and nutrient levels using a well-developed optical imaging technique to spatially and temporally track biofilm growth. We also developed a quantitative method to characterize B. subtilis biofilm morphologies under various growth conditions. To determine biofilm rim irregularities, we used the dimensionless P2A ratio, defined as P2/4πA, where P is the perimeter and A is the area of the biofilm. To estimate biofilm thickness from transmission images, we developed a calibration procedure based on Beer- Lambert’s law and cross sectioning. Furthermore, to determine the distributions of different B. subtilis cell phenotypes during biofilm growth, we used a triple-fluorescence-labeled B. subtilis strain that expressed motility, matrix production, and sporulation. Based on this work, we are able to tune biofilm growth by changing its growing environment.

An OVSF Code Based Routing Protocol for Clustered Wireless Sensor Networks

Yangyang Wang,Xiaoling Wu,Jin Wang,Weiping Liu,Weimin Zheng 보안공학연구지원센터 2012 International Journal of Future Generation Communi Vol.5 No.3

Catalytic performance of amino acid/phosphotungstic acid as bi-functional heterogeneous catalyst for biodiesel production

Qingyu Zhang,Xiaoling Duan,Siyi Tang,Cunwen Wang,Weiguo Wang,Weiliang Feng,Tielin Wang 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.1

In this study, a series of acid-base bi-functional catalysts were prepared by mixing different amounts of basic amino acids (AAs) and phosphotungstic acid (PTA), which exhibited the excellent performance in catalyzing conversion of oleic acid (OA) for the biodiesel production. The physicochemical properties of the catalysts were characterized and analyzed using modern testing techniques and characterization methods such as XRD, FT-IR, XPS, SEM, TEM, and Hammett titration. The various influence parameters were optimized using the central composite design based the response surface methodology, where the maximum biodiesel yield of 97.0% was achieved at the MeOH/OA molar ratio of 5.9, the catalyst loading of 8%, reaction time of 6 h, and reaction temperature of 65℃. Furthermore, the stability and reusability of the prepared catalyst were also demonstrated. At last, the possible catalytic mechanism of the prepared catalyst was comprehensively described.

Uncertainty estimation of reliability redundancy in complex systems based on the Cross-Entropy method

Gui-Bao Wang,Hong-Zhong Huang,Yu Liu,Xiaoling Zhang,Zhonglai Wang 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.10

The article aims to estimate the uncertainty of possible failure events of redundancy systems based on the crossentropy (CE) method. Failure events of subsystems and components always result in the incomplete or complete failure of engineering systems, yet optimal condition monitoring of a complex system is heavily dependent on the accuracy analysis of all the failure events of subsystems and components and their interaction effects. The CE method is a versatile tool for estimating probabilities of rare events in complex systems with the least bias beyond conditional constraints. In this paper we introduce the CE method for analyzing the system reliability with the highest uncertainty among all possibilities satisfying supplied moment constraints, and developed numerical CE algorithms capable of estimating the uncertainty of failure modes in an M-dimensional redundancy system domain with moment constraints of order up to N. A general computational framework of event estimation and condition monitoring of redundancy systems is illustrated in which the Monte Carlo simulations and CE optimization algorithms are combined. Numerical results indicate potential improvements in the measure of the uncertainty of redundancy systems that would lead to the best-fit analysis of all the complete or incomplete failure events.

Phase II Trial of Epigallocatechin-3-Gallate in Acute Radiation-Induced Esophagitis for Esophagus Cancer

Xiaoling Li,Ligang Xing,Yujun Zhang,Peng Xie,Wanqi Zhu,Xiangjiao Meng,Yinxia Wang,Lingling Kong,Hanxi Zhao,Jinming Yu 한국식품영양과학회 2020 Journal of medicinal food Vol.23 No.1

Acute radiation-induced esophagitis (ARIE) is among the most serious form of toxicities associated with definitive radiotherapy or chemoradiotherapy used for treatment of patients with esophageal cancer. Our preliminary phase I and II trials of lung cancer patients who received radiotherapy indicated epigallocatechin-3-gallate (EGCG) as a promising therapeutic option against ARIE. Therefore, we conducted a prospective phase II study to validate the efficacy and safety of EGCG in the treatment of ARIE. The patients who received chemoradiotherapy or definitive radiotherapy for treatment of esophageal cancer in the Shandong Cancer Hospital and Institute in China were enrolled for the present study. EGCG (440 μM) was administered with first onset of ARIE and then at weeks after final radiotherapy. The patients were monitored every week for dysphagia, Radiation Therapy Oncology Group (RTOG) score, and esophagitis-related pain. Moreover, tumor response and the effect on survival following the treatment were also evaluated. Comparison of the RTOG score in the first, second, third, fourth, fifth, and even sixth week after EGCG prescription and the first and second week after radiotherapy with baseline indicates a significant reduction. The tumor response rate was 86.3%. The overall survival rate in 1, 2, and 3 years was found to be 74.5%, 58%, and 40.5%. Oral administration of EGCG solution seems to be feasible for treating ARIE in patients with esophageal cancer who receive radiation therapy. EGCG might be an ARIE-reliever without compromising the efficacy of radiation therapy. A randomized study with a control group is needed for further evaluation.