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Chinese Science Bulletin 2009年第1期54卷 142-149页

作者： qu Bo liu JunXin State key Laboratory of Environment Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences P.O. Box 2871 Beijing 100085 China

Polyhydroxybutyrate (PHB) was produced by activated sludge in a two-stage process. In the first stage,the sludge with high storage potential was enriched in a sequencing batch reactor (SBR) operated by a dynamic feeding regime. The biosynthesis of PHB was sequentially accomplished in a batch reactor in the second stage. This article focused on the optimization of PHB content by evaluating the effects of three critical factors: Dissolved oxygen,pH and food-to-microorganism (F/M) ratio in the batch reactor. The results showed that the rate of substrate uptake,as well as the yield and content of PHB increased with the increase of dissolved oxygen concentration. The control of pH was not necessary under the weak alkaline condition for improvement of PHB content,except for the case in which the pH value was out of rang of 7.0 to 10.0. The enhanced F/M ratio favored PHB accumulation in the range of 1.0 to 4.5 C-mmol/C-mmol and the highest PHB content,64%,was achieved at 4.5 C-mmol/C-mmol. When F/M ratio was enhanced to 6.0 C-mmol/C-mmol,the phenomenon of utilizing simultaneously intracellular PHB and external substrate by sludge was observed,which resulted in a sharp decrease of PHB con-tent. The microscopic observation clearly confirmed that dynamic feeding regime was effective for selecting and enriching the sludge with a high storage potential.

关键词：聚羟基丁酯活性软泥动态加料机制最适宜条件

GUIDELESS SPATIAL COORDINATE MEASUREMENT TECHNOLOGY BASED ON CODING POLE

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Chinese Journal of Mechanical Engineering 2008年第1期21卷 87-90页

作者： ZHAO Min QIU Zongming qu Jiamin liu Hongzhao School of Mechanical Instrumental Engineering Xi＇an University of Technology Xi＇an 710048. China

A new method of guideless spatial coordinate measurement technology based on coding pole and vision measurement is proposed. Unequal spacing of bar code is adopted to pole, so that the code combination of pole image in measuring field is unique. Holographic characteristics of numeric coding pole are adopted to obtain pole pose and pole probe position by any section of bar code on the pole. Spatial coordinates of measuring points can be obtained by coordinate transform. The contradiction between high resolution and large visual field of image sensor is resolved, thereby providing a new concept for surface shape measurement of large objects with high precision. The measurement principles of the system are expounded and mathematic model is established. The measurement equation is evaluated by simulation experiments and the measurement precision is analyzed. Theoretical analysis and simulation experiments prove that this system is characterized by simple structure and wide measurement range. Therefore it can be used in the 3-dimentional coordinate measurement of large objects.

关键词： Coding pole Guideless Coordinate measurement Vision measurement

Simultaneous enhancement of mechanical properties and corrosion resistance of as-cast Mg-5Zn via microstructural modification by friction stir processing

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Journal of Magnesium and Alloys 2023年第6期11卷 1931-1943页

作者： Fei Long Gaoqiang Chen Mengran Zhou Qingyu Shi qu liu State Key Laboratory of Tribology Tsinghua UniversityBejjing 100084China Department of Mechanical Engineering Tsinghua UniversityBejjing 100084China

Magnesium alloys are ideal lightweight materials;however,their applications are extremely limited due to their low strength,poor ductility,and weak corrosion *** the present study,a friction stir processing(FSP)treatment was employed to optimize the mechanical properties and corrosion resistance of an as-cast Mg-5Zn *** average grain size of the Mg-5Zn alloy was refined from 133.8μm to1.3μm as a result of *** different directions,FSP exhibited the enhancement effects on different mechanical ***,according to the potentiodynamic polarization results,the corrosion current density at the free-corrosion potential of the FSPed sample,was 4.1×10^(-6)A/cm^(2)in 3.5 wt.%Na Cl aqueous solution,which was significantly lower than that of the as-cast *** impedance spectroscopy revealed that the polarization impedance,Rp,of the FSPed sample was 1534Ω/cm^(2)in 3.5 wt.%NaCl aqueous solution,which was 71.4%greater than that of the as-cast *** corrosion morphology of the FSPed sample in 3.5 wt.%NaCl aqueous solution exhibited largely uniform corrosion,rather than severe localized corrosion characteristics,which further reduced the corrosion depth on the basis of reducing the corrosion current *** results presented herein indicate that FSP is a viable technique for simultaneously improving the mechanical properties and corrosion resistance of the as-cast Mg-5Zn alloy.

关键词： Friction stir processing Magnesium alloy Corrosionmode Texture softening Anisotropy in mechanical properties

Prognosis control surgery

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Hepatobiliary Surgery and Nutrition 2021年第1期10卷 126-128页

作者： Rong liu qu liu Xiu-Ping Zhang Faculty of Hepato-Biliary-Pancreatic Surgery The First Medical Center of Chinese People’s Liberation Army(PLA)General HospitalBeijingChina

Despite the advent of the Internet and the era of big data,as well as the gradual application of information technology(IT)modalities such as artificial intelligence(AI)to the medical field,traditional medical science research is still predominantly concerned with the experience of the surgeons and takes an evidence-based approach,the impact and challenges of which vary by treatment(1).With the rapid development of medical sciences and technology,new and advanced methods of disease diagnosis and treatment are *** high-tech approaches allow for early diagnosis and treatment,and challenge the classical concepts within their respective *** is important to integrate the clinical experience of the surgeons with high-level evidence-based medical science and IT modalities to achieve optimal therapeutic efficacy through effective management of disease *** long-term clinical application,we here propose the theory of“prognosis control surgery”(PCS)for the routinization of minimally invasive surgery and the simplification of complex surgery,with the aim of achieving the maximum clinical benefit with minimal treatment-related injury to patients.

关键词： surgery diagnosis treatment

Formation and distribution of disinfection by-products during chlorine disinfection in the presence of bromide ion

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Chinese Science Bulletin 2008年第17期53卷 2717-2723页

作者： LI Bo qu JiuHui liu HuiJuan ZHAO Xu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The influences of contact time and pH value on the formation and distribution of four species of trihalomethanes and five species of haloacetic acids during chlorination in the presence of bromine were investigated. Results showed that the distribution of molar fraction of trihalomethanes varied with contact time due to the change of bromide ion concentration during chlorination. Most of the trihalomethanes comprising bromine-containing species and the favored products of the haloacetic acids were chlorine-containing species after 24 h of chlorination. The extent of bromine incorporation in trihalomethanes and haloacetic acids both decreased with time. The contact time also had influence on the formation rate of different species of haloacetic acids. The formation and distribution of trihalomethanes and haloacetic acids strongly depended on the chlorination pH value. All of the trihalomethanes species formation increased with the increase of pH value except the bromoform that had not been detected. The molar fraction of bromodichloromethane and dibromochloromethane containing bromine increased with pH value while chloroform without bromine decreased. Under the pH range studied in this experiment, the predominant haloacetic acids species were trichloroacetic acid and dichloroacetic acid which all decreased with the increase of pH value and the level of TCAA was higher than that of DCAA.

关键词：溴化物消毒余氯氯化作用饮用水处理

Dyes wastewater treatment by reduction-oxidation process in an electrochemical reactor packed with natural manganese mineral

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Journal of Environmental Sciences 2006年第1期18卷 17-22页

作者： WANG Ai-min qu Jiu-hui liu Hui-juan LEI Peng-ju State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A novel technology which combined electrochemical process catalyzed by manganese mineral with electro-assisted coagulation process was proposed in this study. The mineralization of organic pollutant from simulated dye wastewater containing an azo dye Acid Red B（ARB） was experimentally investigated using this method. It was found that the manganese mineral could catalyze the electrochemical process dramatically. The TOC removal percentage of electrochemical treatment catalyzed by manganese mineral was 43.6% while the TOC removal percentage of the process using the manganese mineral alone and using the electrolysis alone were 9.3% and 20.8%, respectively. Moreover, it was found that combined electroxidation with electro-assisted coagulation process could more effectively eliminate ARB. After a period of 180 min electrooxidation and 300 min electroreduction, almost 66.9% of TOC was removed, and the dissolved Mn^2＋. could be effectivly removed. The effects of the order of oxidation and reduction, the proper ratio electrooxidation/reduction time, and current density on the removal efficiency were investigated in detail. In addition, a proposed mechanism of manganese-mineral-catalyzed electrooxidation-reduction process was discussed in this paper.

关键词： manganese mineral electroreduction electrooxidation catalyze Acid Red B

Interface strengthening for thermal sprayed WC-10Co4Cr coating subjected to pulsed magnetic treatment

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Rare Metals 2024年第2期43卷 780-795页

作者： Cheng-Kai Qian qu liu Heng Wang Ke-Jian Li Zhi-Peng Cai Department of Mechanical Engineering Tsinghua UniversityBeijing100084China Tianjin Research Institute for Advanced Equipment Tsinghua UniversityTianjin300304China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing100084China

The reliability of the coated industry components demands ideal fatigue properties of the coating,and it is mainly determined by the performance of the *** this study,pulsed magnetic treatment(PMT)was applied to the thermal sprayed WC-10Co4Cr coating,and the fatigue lifetime of the coated bolt increased by 219.82%under an imitation of the operating mode *** tests further proved that both the adhesion and cohesion strength were improved after PMT,and they benefit from the interface strengthening *** formation of coherent WC/Co interfaces was characterized by in-situ transmission electron microscopy(TEM),and the molecular dynamic simulations indicate that the work of separation of these interfaces is much higher than the original disordered *** stress was relaxed and distributed more homogeneously after PMT,and it mainly contributes to the coating/substrate *** work provides a new post-treatment method focusing on the interfaces in the WC-based coating and gives insight into its mechanism so that it is hopeful to be applied to other kinds of coatings.

关键词： Cemented carbide coating Pulsed magnetic treatment Interface strengthening Fatigue properties Adhesion strength

Capturing the opportunities to initiate an in-depth integration of traditional Chinese medicine and western medicine

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Frontiers of Medicine 2014年第3期8卷 268-271页

作者： Jia-Hua qu Bing liu Zhu-Qin Zhang De-Pei liu State Key Laboratory of Medical Molecular Biology Department of Biochemistry and Molecular Biology Institute of Basic Medical SciencesChinese Academy of Medical Sciences and Peking Union Medical College Beijing 100005 China

Medicine is mainly categorized into traditional Chinese medicine （TCM） from the east and western medicine from the west. The abundant practical experiences and classical medical theories in ancient China show that TCM not only studies the diagnosis, therapy, and prognosis of diseases but also focuses on prevention before disease onset and rehabilitation after therapy. These factors are characterized by the application of treatment methods, including prescription, acupuncture, and moxibustion. By comparison, western medicine utilizes modern instruments and standardized index analytical tools to evaluate diseases and perform quantitative and qualitative research in biological mor- phology and local positioning of life and disease. Therefore, TCM and western medicine are two different medical systems with respective advantages.

关键词： Capturing opportunities initiate in-depth integration

Oxidation Behaviors of Different Grades of Ferritic Heat Resistant Steels in High-Temperature Steam and Flue Gas Environments

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Acta Metallurgica Sinica(English Letters) 2022年第7期35卷 1103-1116页

作者： Xiaogang Li qu liu Shanlin Li Yu Zhang Zhipeng Cai Kejian Li Jiluan Pan Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Collaborative Innovation Center of Advanced Nuclear Energy Technology Tsinghua UniversityBeijing 100084China

For steam tubes used in thermal power plant,the inner and outer walls were operated in high-temperature steam and flue gas environments *** this study,structure,microstructure and chemical composition of oxide films on inner and outer walls of exservice low Cr ferritic steel G102 tube and exservice high Cr ferritic steel T91 tube were *** oxide film was composed of outer oxide layer,inner oxide layer and internal oxidation *** outer oxide layer on the original surface of tube had a porous structure containing Fe oxides formed by diffusion and oxidation of *** specially,the outer oxide layer formed in flue gas environment would mix with coal combustion products during the growth *** inner oxide layer below the original surface of tube was made of Fe–Cr *** internal oxidation zone was believed to be the precursor stage of inner oxide *** formation of internal oxidation zone was due to O diffusing along grain boundaries to form *** were Fe–Cr–Si oxides discontinuously distributed along grain boundaries in the internal oxidation zone of G102,while there were Fe–Cr oxides continuously distributed along grain boundaries in that of T91.

关键词： Ferritic heat resistant steels High temperature service Oxide layer Steam Flue gas Oxidation evolution

Leveraging machine learning techniques for predicting pancreatic neuroendocrine tumor grades using biochemical and tumor markers

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World Journal of Clinical Cases 2019年第13期7卷 1611-1622页

作者： Rui-quan Zhou Hong-Chen Ji qu liu, Chun-Yu Zhu Rong liu School of Medicine Nankai University Tianjin 300071 China The Second Department of Hepatobiliary Surgery Chinese PLA General Hospital Beijing 100853 China

BACKGROUND The incidence of pancreatic neuroendocrine tumors (PNETs) is now increasing rapidly. The tumor grade of PNETs significantly affects the treatment strategy and prognosis. However, there is still no effective way to non-invasively classify PNET grades. Machine learning (ML) algorithms have shown potential in improving the prediction accuracy using comprehensive data. AIM To provide a ML approach to predict PNET tumor grade using clinical data. METHODS The clinical data of histologically confirmed PNET cases between 2012 and 2018 were collected. A method of minimum P for the Chi-square test was used to divide the continuous variables into binary variables. The continuous variables were transformed into binary variables according to the cutoff value, while the P value was minimum. Four classical supervised ML models, including logistic regression, support vector machine (SVM), linear discriminant analysis (LDA) and multi-layer perceptron (MLP) were trained by clinical data, and the models were labeled with the pathological tumor grade of each PNET patient. The performance of each model, including the weight of the different parameters, were evaluated. RESULTS In total, 91 PNET cases were included in this study, in which 32 were G1, 48 were G2 and 11 were G3. The results showed that there were significant differences among the clinical parameters of patients with different grades. Patients with higher grades tended to have higher values of total bilirubin, alpha fetoprotein, carcinoembryonic antigen, carbohydrate antigen 19-9 and carbohydrate antigen 72-4. Among the models we used, LDA performed best in predicting the PNET tumor grade. Meanwhile, MLP had the highest recall rate for G3 cases. All of the models stabilized when the sample size was over 70 percent of the total, except for SVM. Different parameters varied in affecting the outcomes of the models. Overall, alanine transaminase, total bilirubin, carcinoembryonic antigen, carbohydrate antigen 19-9 and

关键词： Machine learning Pancreatic neuroendocrine tumors Tumor grade Biochemical indexes Tumor markers