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Levels and distributions of polychlorinated naphthalenes in sewage sludge of urban wastewater treatment plants

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Chinese Science Bulletin 2008年第4期53卷 508-513页

作者： GUO Li zhang Bing XIAO Ke zhang qinghua ZHENG MingHui State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences ChineseAcademy of Sciences Beijing 100085 China

Over seventy congeners of polychlorinated naphthalenes(PCNs) in sewage sludge of 8 urban waste-water treatment plants(WWTPs) in Beijing were analyzed by isotope dilution,and high resolution gas chromatography/high resolution mass spectrometry(HRGC/HRMS) *** total PCN concentrations determined in the samples range from 1.48 to 28.21 ng/g dw(dry weight) with TEQ concentrations of 0.11―2.45 pg/g *** levels were lower than those found in other *** and TrCNs were the most dominant homologues of *** similar congener profiles in all the samples suggest the similarity in certain *** from industrial input might be the most significant source of PCNs in the sludges in this study,and thermal processes such as waste incineration and coal combustion may be another source of the PCNs contamination.

关键词：污水污泥萘高分辨质谱法高分辨气相色谱分析城市污水处理厂

Domain Wall Evolution in Hf_(0.5)Zr_(0.5)O_(2)Ferroelectrics under Field-Cycling Behavior

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Research 2023年第4期6卷 415-423页

作者： Sirui zhang qinghua zhang Fanqi Meng Ting Lin Binjian Zeng Lin Gu Min Liao Yichun Zhou School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710071China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

HfO_(2)-based ferroelectrics have evoked considerable interest owing to the complementary metal-oxide semiconductor compatibility and robust ferroelectricity down to a few unit ***,the unique wake-up effect of HfO_(2)-based ferroelectric films severely restricts the improvement of their *** particular,the domain structure is an important characteristic of ferroelectric materials,which still has not been well understood in HfO_(2)-based *** this work,a Hf_(0.5)Zr_(0.5)O_(2) ferroelectric thin film is grown on a typical Si substrate buffered with TiN *** 90°domains of the Pca21 ferroelectric phase with head-to-tail and tail-to-tail structures can be observed by Cs-corrected scanning transmission electron microscope under their pristine *** waking up,the 180°domain is displayed in the ferroelectric *** remarkable differences in domain walls for 90°and 180°domains are characterized by qualitatively mapping the polarization distributions at the atomic *** domain wall changes from the[101]of the Hf_(0.5)Zr_(0.5)O_(2) film to the[001]of the Hf_(0.5)Zr_(0.5)O_(2) *** result provides fundamental information for understanding the domain structure of HfO_(2)-based ferroelectrics.

关键词： ferroelectric film walls

Patterns and levels of PCDD/F in a Chinese graphite electrode sludge

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Chinese Science Bulletin 2000年第16期45卷 1471-1476页

作者： Ying Xu qinghua zhang Wenzhong Wu Wen Li Chinese Acad Sci Inst Hydrobiol State Key Lab Freshwater Ecol & Biotechnol Wuhan 430072 Peoples R China

The graphite electrode sludge was sampled from a huge chloralkali plant in central China. The total level of PCDD/F was found as high as 378.85 ng/kg sludge (dry weight). The patterns of PCDD/F in each homologue indicated the predominance of tetra- to octa-chlorinated PCDFs. Furthermore, the toxic 2,3,7,8-substituted PCDFs constituted over 80% of the total PCDFs in the sludge and the corresponding PCDDs were only at 15 |ig/kg level. The calculated value of the international toxic equivalence (I-TEQ) in sludge was 21.65 (ig/kg sludge (dry weight). This typical 'dioxin chloralkali pattern' was apparently identified in the sediments near the effluent outlet of the chloralkali plant.

关键词： graphite PCDD/F chloralkali contamination.

Leader-follower: Human-centered intention-guided controller for novel SuperLimb with application to load-carrying scenarios

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Science China Technological Sciences 2025年第1期 325-338页

作者： qinghua zhang Xianglong LI Hongwei JING Kerui SUN Yuancheng LI Sikai ZHAO Lele LI Haotian JU Ziqi WANG Rui WU Tianjiao ZHENG Jie ZHAO Yanhe ZHU The State Key Laboratory of Robotics and System Harbin Institute of Technology The Learning Algorithms and Systems Laboratory School of Engineeringécole Polytechnique Fédérale de Lausanne

Supernumerary robotic arms(SuperLimb) are a new type of wearable robot that works closely with humans as a third hand to augment human operation capability. Accurate conveyance of wearers' intentions, allocation of roles, and humancentered interaction considerations are the key points in the process of human–SuperLimb collaboration. This paper proposes a human-centered intention-guided leader–follower controller that relies on the dynamic modeling of SuperLimb with application to load-carrying scenarios. The proposed leader–follower controller takes the human as the leader and the SuperLimb as the follower, achieving effective information communication, autonomous coordination, and good force compliance between SuperLimb, humans, and the environment under human safety assurance. First, the human–SuperLimb dynamic system is modeled to achieve force interaction with the environment and wearer. Second, to achieve the precise intention extraction of humans, pose data from five visual odometry sensors are fused to capture the human state, the generalized position, the velocity of hands, and the surface electromyography signals from two myoelectric bracelets sensors are processed to recognize the natural hand gestures during load-carrying scenarios by a designed Swin transformer network. Then, based on the real-time distance detection between human and mechanical limbs, the security assurance and force-compliant interaction of the human–SuperLimb system are realized. Finally, the human hand muscle intention recognition, human–robot safety strategy verification,and comparative load-carrying experiments with and without the proposed method are conducted on the SuperLimb *** showed that the task parameters are well estimated to produce more reasonable planning trajectories, and SuperLimb could well understand the wearer's intentions to switch different SuperLimb actions. The proposed sensor-based human–robot communication framework motivates future studies of o

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Laser melted oxide ceramics:Multiscale structural evolution with non-equilibrium features

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Journal of Materiomics 2019年第3期5卷 436-445页

作者： Lu Song Jing Ma qinghua zhang Zhijian Shen State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China Department of Materials and Environmental Chemistry Arrhenius LaboratoryStockholm UniversityStockholm10691Sweden

Compared with the versatility in metal industry,application of laser on oxide ceramics is quite limited due to the intrinsic features of ceramics and limited understanding in laser-ceramic interaction mechanism,especially for high-energy laser that causes melting of *** this research,a study into general behaviors of several oxide ceramics melted by laser under inert atmosphere is *** factors in determining state transformation,chemical reduction and phase structure are summarized,with further investigation into the evolution in microstructure at multiscale and the corresponding novelty and *** is found that laser melting does show great potential in introducing deep reduction,unique microstructure,and notable increase in structure complexity and total entropy,and those features could contribute to some unconventional functional performance with brand-new structure-property relationship.

关键词： Laser Oxide ceramic Heterogeneity Defects Non-equilibrium

Continuous Surface Metallization of Polyimide Fibers for Textile‑Substrate Electromagnetic Shielding Applications

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Advanced Fiber Materials 2023年第6期5卷 1892-1904页

作者： Shixu Zhou Jie Dong Xiuting Li Xin Zhao qinghua zhang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua University201620 ShanghaiPeople’s Republic of China

Despite tremendous effort,continuous fabrication of high-performance conductive polymer fibers for electromagnetic interference(EMI)shielding applications remains a daunting technical *** the current study,we report an efficient strategy for continuous surface metallization of polyimide fibers used in textile-substrate electromagnetic shielding *** fibers with pendent carboxyl groups(PIC)were first fabricated,and a conductive nickel layer was continuously coated on the PIC surface by electroless metal deposition(ELD).The carboxyl groups introduced onto the fiber surface acted as binding sites for the Ni^(2+)ions,and the complexation reactions greatly increased the Ni^(2+)adsorption capacity and efficiency of the PIC fibers during the ELD process and ensured continuous *** judicious control of the plating time,a series of nickel-layer-coated PIC fibers(Ni-PIC)were constructed with Ni loadings ranging from 20 to 230 wt%.The resultant Ni-PIC fiber containing 65 wt%Ni exhibited conductivity of 223 S cm^(−1),and the corresponding fabric exhibited an EMI shielding effectiveness(EMI SE)of 44 dB in the *** corresponding EMI SE was further improved to 83 dB after the fiber was treated at 300℃ for 1 h because of the crystallization of the Ni *** prepared Ni-PIC fibers and fabrics were also used in pressure sensors and electrothermal conversion,which demonstrated outstanding adaptabilities to various temperatures and mechanical ***,this work provides an efficient route for developing high-performance conductive polyimide fibers for EMI shielding applications,especially for use in military and aerospace equipment and in other harsh environments.

关键词： Polyimide Carboxyl group Nickel layer Electroless metal deposition EMI shielding

Porous Pt nanoframes decorated with Bi(OH)3 as highly efficient and stable electrocatalyst for ethanol oxidation reaction

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Nano Research 2020年第1期13卷 265-272页

作者： Xiaolei Yuan Bei Jiang Muhan Cao Congyang zhang Xiaozhi Liu qinghua zhang Fenglei Lyu Lin Gu Qiao zhang School of Chemistry and Chemical Engineering Nantong University9 Seyuan RoadNantong226019China Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSWC for Synchrotron Radiation ResearchSoochow University199 Ren’ai RoadSuzhou215123China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100049China Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

High-quality Pt-based catalysts are highly desirable for ethanol oxidation reaction(EOR),which is of critical importance for the commercial applications of direct ethanol fuel cells(DEFCs).However,most of the Pt-based catalysts have suffered from high cost and low operation *** a two-step method has been developed to synthesize porous Pt nanoframes decorated with Bi(OH)3,which show excellent catalytic activity and operation durability in both alkaline and acidic *** example,the nanoframes show a mass activity of 6.87 A·mgPt−1 in alkaline media,which is 13.5-fold higher than that of commercial Pt/*** importantly,the catalyst can be reactivated simply,which shows negligible activity loss after running for 180,000 *** in situ attenuated total reflection-infrared(ATR-IR)absorption spectroscopy and CO-stripping experiments indicate that surface Bi(OH)3 species can greatly facilitate the formation of adsorbed OH species and subsequently remove carbonaceous poison,resulting in a significantly enhanced stability towards *** work may favor the tailoring of desired electrocatalysts with high activity and durability for future commercial application of DEFCs.

关键词： Pt nanoframe ethanol oxidation reaction bismuth hydroxide CO tolerance in situ infrared spectroscopy durability

Novel biomonitoring method for determining five classes of legacy and alternative flame retardants in human serum samples

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Journal of Environmental Sciences 2023年第9期131卷 111-122页

作者： Xiaolin Guan Gaoxin zhang Lingling Meng Mei Liu Liyuan zhang Chuxuan Zhao Yingming Li qinghua zhang Guibin Jiang Key Laboratory of Eco-Environment-Related Polymer Materials Ministry of Education Key Laboratory of Polymer Materials Ministry of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Endocrinology and Metabology The First Affiliated Hospital of Shandong First Medical University&Shandong Provincial Qianfoshan HospitalJinan 250014China University of Chinese Academy of Sciences Beijing 100049China

Flame retardants(FRs)are ubiquitous in environment and biota and may pose harm to human *** recent years,concern regarding legacy and alternative FRs has been intensified due to their widespread production and increasing contamination in environmental and human *** this study,we developed and validated a novel analytical method for simultaneous determination of legacy and alternative FRs,including polychlorinated naphthalenes(PCNs),short-and middle-chain chlorinated paraffins(SCCPs and MCCPs),novel brominated flame retardants(NBFRs),and organophosphate esters(OPEs)in human *** samples were prepared by liquid-liquid extraction using ethyl acetate,and purified with Oasis®HLB cartridge and Florisil–silica gel *** analyses were carried out using gas chromatography-triple quadrupole mass spectrometry,highresolution gas chromatography coupled with high-resolution mass spectrometry,and gas chromatography coupled with quadrupole time-of-flight mass spectrometry,*** proposed method was validated for linearity,sensitivity,precision,accuracy,and matrix *** detection limits for NBFRs,OPEs,PCNs,SCCPs,and MCCPs were 4.6×10^(–4)–8.6×10^(–2),4.3×10^(–3)–1.3,1.1×10^(–5)–1.0×10^(–4),1.5,and 9.0×10–1 ng/mL,*** spike recoveries ranged from 73%–122%,71%–124%,75%–129%,92%–126%,and 94%–126%for NBFRs,OPEs,PCNs,SCCPs,and MCCPs,*** analytical method was applied for detection of real human *** were the dominant FRs in serum,indicating CPs were widely presented in human serum and should be pay more attention for their health risk.

关键词： Human serum Biomonitoring Novel brominated flame retardants Organophosphate esters Chlorinated paraffins Polychlorinated naphthalenes

Selective kernel networks for weakly supervised relation extraction

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CAAI Transactions on Intelligence Technology 2021年第2期6卷 224-234页

作者： Ziyang Li Feng Hu Chilong Wang Weibin Deng qinghua zhang Chongqing Key Laboratory of Computational Intelligence Chongqing University of Posts and TelecommunicationsChongqingChina

The purpose of relation extraction is to identify the semantic relations between entities in sentences that contain two ***,many variants of the convolution neural network(CNN)have been introduced to relation extraction for the extracting of features--the quality of the neural network model directly affects the final quality of relation ***,the traditional convolution network uses a fixed convolution kernel,so it is difficult to choose the size of the convolution kernel dynamically,which results in networks with weak representation *** address this,a novel CNN is designed with selective kernel networks and *** the process of feature extraction,the model can adaptively select the size of the convolution kernel,that is,give more weight to the appropriate convolution *** is then combined with multigranularity convolution to obtain more abundant semantic ***,a new pooling method is designed to obtain more comprehensive information and improve model *** results indicate that this method is effective without excessively deep network layers,and it also outperforms several competitive baseline methods.

关键词： kernel convolution relation