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Effect of powdered activated carbon on Chinese traditional medicine wastewater treatment in submerged membrane bioreactor with electronic control backwashing

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Journal of Environmental Sciences 2007年第9期19卷 1037-1042页

作者： LIU Xiao-lei ren Nan-qi MA Fang School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China. School of Water Conservancy and Environment Engineering Changchun Institute of Technology Changchun 130012 China

Chinese traditional medicine wastewater, rich in macromolecule and easy to foam in aerobic biodegradation such as Glycosides, was treated by two identical bench-scale aerobic submerged membrane bioreactors （SMBRs） operated in parallel under the same feed, equipped with the same electronic control backwashing device. One was used as the control SMBR （CSMBR） while the other was dosed with powdered activated carbon （PAC）（PAC-amended SMBR, PSMBR）. The backwashing interval was 5 min. One suction period was about 90 min by adjusting preestablished backwashing vacuum and pump frequency. The average flux of CSMBR during a steady periodic state of 24 d （576 h） was 5.87 L/h with average hydraulic residence time （HRT） of 5.97 h and that of PSMBR during a steady periodic state of 30 d （720 h） was 5.85 L/h with average HRT of 5.99 h. The average total chemical oxygen demand （COD） removal efficiency of CSMBR was 89.29% with average organic loading rate （OLR） at 4.16 kg COD/（m^3.d） while that of PSMBR was 89.79% with average OLR at 5.50 kg COD/（m^3.d）. COD concentration in the effluent of both SMBRs achieved the second level of the general wastewater effluent standard GB8978-1996 for the raw medicine material industry （300 mg/L）. Hence, SMBR with electronic control backwashing was a viable process for medium-strength Chinese traditional medicine wastewater treatment. Moreover, the increasing rates of preestablished backwashing vacuum, pump frequency, and vacuum and flux loss caused by mixed liquor in PSMBR all lagged compared to those in CSMBR; thus the actual operating time of the PSMBR system without membrane cleaning was extended by up to 1.25 times in contrast with the CSMBR system, and the average total COD removal efficiency of PSMBR was enhanced with higher average OLR.

关键词： electronic control backwashing powdered activated carbon membrane bioreactor aerobic process wastewater treatment

CW interference mitigation in GNSS receiver based on frequency-locked loop

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Science China(Information Sciences) 2016年第8期59卷 117-132页

作者： Hongyu ren Yongqing WANG lei JIANG Siliang WU School of Information and Electronics Beijing Institute of Technology

Global navigation satellite system(GNSS) receivers are highly susceptible to continuous wave(CW)interference because the received signals are extremely weak. Current interference mitigation techniques mainly use a notch filter or transform domain. This paper proposes a computationally effective algorithm based on a frequency-locked loop(FLL) to mitigate interference in GNSS receivers. The performance of the algorithm is validated through an analysis of the characteristics of the interference reduction filter and interference estimation precision. A Monte Carlo simulation is used to compare the proposed algorithm with various previous algorithms:the adaptive IIR notch filter, adaptive linear-phase FIR filter, and N-sigma DFT algorithm. The simulation results show that the proposed algorithm exhibits excellent interference estimation precision and superior antijamming performance compared with the conventional algorithms.

关键词： continuous wave mitigation frequency-locked loop interference reduction filter interference estimation code tracking

Numerical Simulation of the Effect of Bionic Serrated Structures on the Aerodynamic Noise of a Circular Cylinder

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Journal of Bionic Engineering 2012年第1期9卷 91-98页

作者： lei Shi Chengchun Zhang Jing Wang Luquan ren Key Laboratory of Engineering Bionics （Ministry of Education China） Jilin University Changchun 130022 P. R. China Faculty of Agriculture Jilin University Changchun 130062 P. R. China

Flow control can effectively reduce the aerodynamic noise radiated from a circular cylinder. As one of the flow control methods, a bionic method, inspired by the serrations at the leading edge of owls＇ wing, was proposed in this paper. The effects of bionic serrated structures arranged on the upper and lower sides of a cylinder on the aerodynamic and aeroacoustic performance of the cylinder were numerically investigated. At a free stream speed of 24.5 m.s-1, corresponding to Reynolds number of 1.58 × 10^4, the simulation results indicate that the bionic serrated structures can decrease the frequency of the vortex shedding and control the fluctuating aerodynamic force acting on the cylinder, thus reduce the aerodynamic noise. A qualitative view of the vorticity in the wake of the cylinder suggest that the serrated structures reduce aerodynamic sound by suppressing the unsteady motion of vortices.

关键词： circular cylinder bionic serrated structures aerodynamic noise flow control owl wing

Robustness analysis of underground powerhouse construction simulation based on Markov Chain Monte Carlo method

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Science China(Technological Sciences) 2016年第2期59卷 252-264页

作者： zhong DengHua BI lei YU Jia ZHAO MengQi State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

Scheduling is a major concern in construction planning and management, and current construction simulation research typically targets the shortest total duration. However, uncertainties are inevitable in actual construction, which may lead to discrepancies between the actual and planned schedules and increase the risk of total duration delay. Therefore, developing a robust construction scheduling technique is of vital importance for mitigating disturbance and improving completion probability. In the present study, the authors propose a robustness analysis method that involves underground powerhouse construction simulation based on the Markov Chain Monte Carlo(MCMC) method. Specifically, the MCMC method samples construction disturbances by considering the interrelationship between the states of parameters through a Markov state transition probability matrix, which is more robust and efficient than traditional sampling methods such as the Monte Carlo(MC) method. Additionally, a hierarchical simulation model coupling critical path method(CPM) and a cycle operation network(CYCLONE) is built, using which construction duration and robustness criteria can be calculated. Furthermore, a detailed measurement method is presented to quantize the robustness of underground powerhouse construction, and the setting model of the time buffer is proposed based on the MCMC method. The application of this methodology not only considers duration but also robustness, providing scientific guidance for engineering decision making. We analyzed a case study project to demonstrate the effectiveness and superiority of the proposed methodology.

关键词： underground powerhouse construction schedule simulation model MCMC method robustness

A machine learning approach to query generation in plagiarism source retrieval

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Frontiers of Information Technology & Electronic Engineering 2017年第10期18卷 1556-1572页

作者： lei-lei KONG Zhi-mao LU Hao-liang QI zhong-yuan HAN College of Information and Communication Engineering Harbin Engineering University Harbin 150001 China School of Computer Science and Technology Heilongjiang Institute of Technology Harbin 150050 China State Key Laboratory of Digital Publishing Technology Beijing 100871 China

Plagiarism source retrieval is the core task of plagiarism detection. It has become the standard for plagiarism detection to use the queries extracted from suspicious documents to retrieve the plagiarism sources. Generating queries from a suspicious document is one of the most important steps in plagiarism source retrieval. Heuristic-based query generation methods are widely used in the current research. Each heuristic-based method has its own advantages, and no one statistically outperforms the others on all suspicious document segments when generating queries for source retrieval. Further improvements on heuristic methods for source retrieval rely mainly on the experience of experts. This leads to difficulties in putting forward new heuristic methods that can overcome the shortcomings of the existing ones. This paper paves the way for a new statistical machine learning approach to select the best queries from the candidates. The statistical machine learning approach to query generation for source retrieval is formulated as a ranking framework. Specifically, it aims to achieve the optimal source retrieval performance for each suspicious document segment. The proposed method exploits learning to rank to generate queries from the candidates. To our knowledge, our work is the first research to apply machine learning methods to resolve the problem of query generation for source retrieval. To solve the essential problem of an absence of training data for learning to rank, the building of training samples for source retrieval is also conducted. We rigorously evaluate various aspects of the proposed method on the publicly available PAN source retrieval corpus. With respect to the established baselines, the experimental results show that applying our proposed query generation method based on machine learning yields statistically significant improvements over baselines in source retrieval effectiveness.

关键词： Plagiarism detection Source retrieval Query generation Machine learning Learning to rank

Microstructure and texture evolution of TRC A8006 alloy by homogenization

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International Journal of Minerals,Metallurgy and Materials 2013年第5期20卷 433-439页

作者： zhong-wei Chen Jing Zhao Xiao-lei Hao State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The microstructure and texture evolution of twin-roll cast A8006 alloy by homogenization were characterized using scanning and transmission electron microscopy, and the microhardness was tested as well. According to the relation- ship between dendritic arm spacing and cooling rate the cooling rate of the as-cast twin-roll cast A8006 sheet of 6 mm in thickness was estimated as 1.48×10^3 K·s^-1. It is found that the grains and the nanostructural precipitates of the twin-roll cast sheet become coarser after homogenization at 580℃ for 4 h in comparison with those after homogenization at 500℃ for 8 h. The textures formed after cold rolling and became weaker during homogenization. The increase in hardness of the as-cast twin-roll cast sheets is related in hardness after homogenization can to the supersaturated a-A1 solid solution and be attributed to the coarsening of grains and fine microstructure, but the decrease Al6Fe（Mn） precipitates.

关键词： aluminum alloys homogenization microstructure textures hardness

Regulation and function of endoplasmic reticulum autophagy in neurodegenerative diseases

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Neural Regeneration Research 2025年第1期20卷 6-20页

作者： Xiu-Yun Zhao De-En Xu Ming-lei Wu Ji-Chuan Liu Zi-Ling Shi Quan-Hong Ma Department of Neurology and Clinical Research Center of Neurological Disease the Second Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Neuroscience&Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases Soochow UniversitySuzhouJiangsu ProvinceChina Department of Neurology Jiangnan University Medical CenterWuxiJiangsu ProvinceChina

The endoplasmic reticulum,a key cellular organelle,regulates a wide variety of cellular *** reticulum autophagy,one of the quality control systems of the endoplasmic reticulum,plays a pivotal role in maintaining endoplasmic reticulum homeostasis by controlling endoplasmic reticulum turnover,remodeling,and *** this review,we briefly describe the endoplasmic reticulum quality control system,and subsequently focus on the role of endoplasmic reticulum autophagy,emphasizing the spatial and temporal mechanisms underlying the regulation of endoplasmic reticulum autophagy according to cellular *** also summarize the evidence relating to how defective or abnormal endoplasmic reticulum autophagy contributes to the pathogenesis of neurodegenerative *** summary,this review highlights the mechanisms associated with the regulation of endoplasmic reticulum autophagy and how they influence the pathophysiology of degenerative nerve *** review would help researchers to understand the roles and regulatory mechanisms of endoplasmic reticulum-phagy in neurodegenerative disorders.

关键词： autophagy endoplasmic reticulum endoplasmic reticulum autophagy endoplasmic reticulum quality control system endoplasmic reticulum receptors endoplasmic reticulum-associated degradation neurodegeneration neurodegenerative disease selective autophagy unfolded protein response

Low-temperature molten salt synthesis and luminescence properties of Eu(Ⅲ)-based coordination polymer nanosheets

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Rare Metals 2021年第3期40卷 728-735页

作者： lei Wang Hao Liu Shuang Huang Sheng-Liang zhong College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China

In this work,Eu(III)-based coordination polymer(EuCP) nanosheets were successfully synthesized using tetrabutylammonium bromide(TBAB) as low-temperature molten salt(LMS),terephthalic acid(PTA) and pyromellitic acid(PMA) as organic building blocks at 160℃.X-ray diffraction(XRD),Fourier transform infrared(FTIR),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and thermogravimetry and differential thermal analysis(TG-DTA) were used to characterize the obtained *** show that the nanosheets have an average size of 200 nm and a thickness of about 50 *** effect of reaction temperature,reaction time and molar ratio of Eu^(3+)/PTA/PMA on the preparation was *** turns out that all of them have great effect on morphology and size of the final *** excited with 315 nm,strong emission centering at 617 nm is ***,this synthetic methodology may offer a new alternative in the preparation of rare earth nanomaterials.

关键词： Molten salt Coordination polymer Rare earth Nanosheets

The potential mechanism and clinical application value of remote ischemic conditioning in stroke

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Neural Regeneration Research 2025年第6期20卷 1613-1627页

作者： Yajun Zhu Xiaoguo Li Xingwei lei Liuyang Tang Daochen Wen Bo Zeng Xiaofeng Zhang Zichao Huang Zongduo Guo The First Affiliated Hospital of Chongqing Medical University ChongqingChina

Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may be related to neuroinflammation, cellular immunity, apoptosis, and autophagy, the exact underlying molecular mechanisms are unclear. This review summarizes the current status of different types of remote ischemic conditioning methods in animal and clinical studies and analyzes their commonalities and differences in neuroprotective mechanisms and signaling pathways. Remote ischemic conditioning has emerged as a potential therapeutic approach for improving stroke-induced brain injury owing to its simplicity, non-invasiveness, safety, and patient tolerability. Different forms of remote ischemic conditioning exhibit distinct intervention patterns, timing, and application range. Mechanistically, remote ischemic conditioning can exert neuroprotective effects by activating the Notch1/phosphatidylinositol 3-kinase/Akt signaling pathway, improving cerebral perfusion, suppressing neuroinflammation, inhibiting cell apoptosis, activating autophagy, and promoting neural regeneration. While remote ischemic conditioning has shown potential in improving stroke outcomes, its full clinical translation has not yet been achieved.

关键词： Akt apoptosis autophagy cerebral perfusion cerebral vascular stenosis clinical transformation hemorrhagic stroke ischemic stroke neuroinflammation neuroprotection Notch1 PI3K remote ischemic conditioning stroke