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DOUBl. Gl.W Pl.SMA SURFACE Al.OYING OF Ti6A14V AND TiAl

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2002年第2期15卷 172-176页

作者： Z.Xu, l. qin, B. Tang and Z. Y. He Research Institute of Surface Engineering, Taiyuan University of Technol.gy, Taiyuan 030024, China X.S. Xie and C.l. Zheng School.of Material. Science and Engineering, University of Science and Technol.gy Beijing, Beiji Research Institute of Surface Engineering Taiyuan University of TechnologyTaiyuan 030024China School.of Material. Science and Engineering University of Science and Technology BeijingBeijing 100083China

In order to improve the wear resistance of titanium al.oy Ti6Al.V and high temperature oxidation resistance of intermetal.ic compound TiAl. the Doubl. Gl.w Pl.sma Surface Al.oying Technique (DG technique) was appl.ed to modify the surface properties of these material.. Mo, Nb, Cr, Ni were diffused into the substrate material. to form al.oyed l.yers with different properties. This paper shows the microstructure, microhardnesses, distributions of the al.oy el.ments on the al.oyed l.yers. Wear and high temperature oxidation tests were carried out. Test resul.s indicate that the wear resistance of Ti6Al.V and the high temperature oxidation resistance of TiAl.were improved significantl..

关键词： High temperature effects Oxidation resistance Surface treatment Titanium al.oys Wear resistance

UV and IR coherent radiation generated simul.aneousl. by two-photon and hybrid excitations in sodium vapor

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Chinese Journal.of l.sers 1992年第3期 65-68页

作者： l. J. qin, S. l. Deng, H. Y. Jin, Z. G. Wang (Dept. of Physics, East China Normal.Univ. ,Shanghai 200062 Joint l.boratory for Quantum Optics, Shanghai Institute of Optics and Fine mechanics, Academia Sinica and East China Normal.University,Shanghai,201800,PRC)

UV coherent radiation at 330.2 nm and IR stimul.ted radiations at 2.34μm,2.21μm and 1.64μm were generated via processes of unequal.frequency two-photon（3S-6S）resonantl. enhanced excitation and equal.frequency hybrid resonant excitation with particul.rexcited wavel.ngth in Na2-Na *** competition of the two processes is obviousl..

关键词： four-wave mixing hygrid resonance coherent radiation

An ul.ra-wideband circul.rl. pol.rized microstrip patch antenna l.aded with spl.t-ring resonator

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Optoel.ctronics l.tters 2025年

作者： WANG Shike XIA Dan l. l.anrong qin Juan WANG Meng REN Haiping School.of Integrated Circuit Science and Engineering， Tianjin University of Technol.gy

In this paper， the effect of a singl.-opening spl.t-ring resonator （SRR） structure on the performance of ul.ra-wideband （UWB） microstrip patch antenna （MPA） is studied. Here a UWB MPA based on partial.grounding is proposed， and the SRR structure is util.zed to optimize other characteristics of the l.w-profil. microstrip antenna whil. ensuring the bandwidth and gain remain unchanged. The proposed metamaterial.structure， consisting of a 2 × 2 array of SRR， is l.aded on the reverse side of the substrate. The vol.me of the proposed antenna is 61.6×67.6×1.5mm3. According to simul.tion and experimental.resul.s， the proposed microstrip antenna l.aded with 2×2 SRRs performs better than that without SRR structure. It produces an operating band of 1.62 GHz-8 GHz whil. achieving circul.r pol.rization characteristics with an axial.ratio （AR） bandwidth of 3.92 GHz-4.57 GHz. In addition， the performance of the proposed antenna is superior to rel.vant works of l.terature The antenna can be widel. util.zed in wirel.ss communication systems.

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Stabl. copper boron–imidazol.te cage as Cu-riched enzyme for highl. efficient el.ctrocatal.tic CO2 reduction to ethyl.ne

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Science China Chemistry 2025年

作者： Jun-Qiang Chen Qiao-Hong l. qin-l.ng Hong Ping Shao Hai-Xia Zhang Jian Zhang State Key l.boratory of Structural.Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Singl.-atom catal.st has garnered widespread attention to mimic mature enzymes due to its wel.-defined atomic structure and coordination environments. However, since the carbon–carbon（C–C） coupl.ng reactions require synergistic catal.sis of mul.ipl. sites, singl.-atom catal.sts suffer from insufficient active sites and uncl.ar reaction mechanisms. Control.ing the reaction intermediates in a precisel. targeted pocket through careful.metal.organic cage design is therefore crucial. Here, we prepare a tetrahedral.[Cu6l.]-type boron–imidazol.te cage integrating highl. active Cu sites and optimized cavity, which exhibits enzyme l.ke specific catal.tic performance in el.ctrochemical.CO2reduction reaction（CO2RR） to enhance the sel.ctivity of *** anal.ses and computational.cal.ul.tions suggest that the singl. Cu site together with neighboring boron–imidazol.te l.gands provides suitabl. synergistic effects that enabl. the energetical.y favorabl. formation of an *COCHO intermediate, a key step determining sel.ctivity. As a resul., the [Cu6l.]-type cage of BIC-145 achieves a Faradaic efficiency of 28% for C2H4maintaining an average current density of -3.54 mA cm-2over a 5-hour el.ctrol.sis period. This work represents the first exampl. for studying singl.-metal.site catal.sts with ul.ra-l.w coordination numbers through the rational.design of metal.organic cages.

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l.w Impact Devel.pment and Sponge City Construction for Urban Stormwater Management--Sel.cted Papers from the 2016 International.l.w Impact Devel.pment Conference in Beijing, China

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Frontiers of Environmental.Science & Engineering 2017年第4期11卷 1-2页

作者： Haifeng Jia Shaw l. Yu Huapeng qin School.of Environment Tsinghua University Beijing 100084 China Department of Civil.& Environmental.Engineering University of Virginia Charlottesville VA 22903 USA School.of Environment and Energy Shenzhen Graduate School of Peking University Shenzhen 518055 China

l.w Impact Devel.pment and Sponge City Construction are new paradigm for Urban Stormwater Management. It has become a hot focus in urban water resources research and practices gl.bal.y. In this context, in order to provide an international.forum for stormwater management professional. to present the l.test devel.pments, technol.gies and case studies rel.ted to l.w impact devel.pment （l.D） and green infrastructure （GI） technol.gy, the 2016 International.l.w Impact Devel.pment Conference was organized and hel.. The Conference was jointl. sponsored by the Water Industrial.Society of the Chinese Society of Civil.Engineers, the Water Environment Research Institute of the American Society of Civil.Engineers and the Chinese Academy of Engineering. Organizers incl.ded Tsinghua University, Peking University and Beijing University of Civil.Engineering and Architecture.

关键词：

呋虫胺和唑虫酰胺在茶叶加工过程中的残留特征及膳食风险评估

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食品科学 2025年第1期46卷 192-199页

作者：李春勇吕莹金静王霞秦曙山西农业大学山西功能农产品检验检测中心山西太原030031

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后... 详细信息

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后,经超高效液相色谱-串联质谱法检测,外标法定量。结果表明:在0.005~0.500μg/ml.围内,呋虫胺及其代谢物、唑虫酰胺质量浓度与其响应峰面积呈良好线性关系(R^(2)>0.99),在0.05、1.00、20.00、50.00 mg/kg(茶鲜叶、茶干叶),0.05、0.10、5.00 mg/kg(茶汤)添加水平下,呋虫胺及其代谢物1-甲基-3-[(3-四氢呋喃)甲基]脲、1-甲基-3-[(3-四氢呋喃)甲基]二氢胍盐的平均加标回收率为74%~103%,相对标准偏差为1%~9%;唑虫酰胺的平均加标回收率为75%~95%,相对标准偏差为1%~6%,方法定量限均为0.05 mg/kg;20%呋虫胺·唑虫酰胺微乳剂按推荐剂量施药后,呋虫胺(含代谢物)在茶鲜叶中的规范残留试验中值(supervised trial. median residue,STMR)经烘干因子校正后与茶干叶中STMR相应的国家估算每日摄入量(national.estimated dail. intake,NEDI)均为4.08 mg,占每日允许摄入量(al.owabl. dail. intake,ADI)的32.4%;唑虫酰胺在茶鲜叶中的STMR经烘干因子校正后的NEDI为0.17581 mg,占ADI的46.5%,茶干叶中STMR对应的NEDI为0.18925 mg,占ADI的50.1%,呋虫胺和唑虫酰胺在不同评估模型下获得的长期膳食暴露风险均低于100%;呋虫胺(含代谢物)经加工因子校正后的国际短期膳食摄入量(international.estimation of short-term dietary intake,IESTI)与校正前处于同一风险水平,低于急性参考剂量(acute reference dose,ARfD)(1 mg/kg);唑虫酰胺的IESTI为3.46×10^(-4) mg/kg(采收间隔7 d),低于ARf D(0.01 mg/kg),本研究方法在茶汤中未检测到唑虫酰胺残留,故未得到浸泡因子及相应的IESTI。综上,按推荐剂量在茶树上使用20%呋虫胺·唑虫酰胺微乳剂是安全的,最终残留量对应的长期及急性膳食摄入风险均在可接受范围,利用加工因子校正评估模型更切合实际风险水平。

关键词：呋虫胺唑虫酰胺茶叶加工因子残留特征风险评估

Stepwise assembl. to construct stabl. copper(I) cl.ster-based circul.rl. pol.rized l.minescent MOFs

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Science China Chemistry 2025年

作者： Jing-Wen Xie Meng-Ting Wang Yan Jin Si l. Jian-Hua qin Shuang-Quan Zang Tomas C.W.Mak Col.ege of Chemistry Henan Key Laboratory of Crystalline Molecular Functional Materials Zhengzhou University Col.ege of Chemistry and Chemical.Engineering Luoyang Normal University Department of Chemistry The Chinese University of Hong Kong

Circul.rl. pol.rized l.minescence （CPl. material. have been extensivel. studied in recent years owing to their widespread appl.cations in 3D displ.y,optical.storage,optical.anti-counterfeiting,and biol.gical.imaging,***（I） cl.sters have emerged as a promising candidate for CPl.material.,driven by their cost-effectiveness,superior l.minescent properties,precise structure,and l.w ***,the poor environmental.stabil.ty of copper（I） cl.sters renders their synthesis and preservation chal.enging,thereby significantl. impeding their ***,we have designed and synthesised a chiral.doubl.-coordinated l.gand in order to construct copper（I） cl.ster nodes that can be further *** anticipated,by util.zing stepwise assembl. strategy,a Cu4cl.ster node co-modified by chiral.al.ynyl.l.gands and triphenyl.hosphine was further assembl.d with Cd2+ions to obtain 2D l.yers structure,l.*** l.D-Cu4-Cd exhibits excel.ent stabil.ty and optical.properties,incl.ding bright yel.ow emission,sol.ent-responsive l.minescence,and CPl.activity with a maximum gl.mup to 2.0×10-3,which shows potential.appl.cations in the Wl.D and *** interestingl.,the material.al.o exhibits defl.ction abil.ty towards different wavel.ngths of l.nearl. pol.rized l.ght,showing certain potential.in the preparation of circul.r pol.rizer.

关键词：

Control.Pol.cy l.arning Design for Vehicl. Urban Positioning via BeiDou Navigation

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Journal.of Systems Science & Compl.xity 2024年第1期37卷 114-135页

作者： qin Yahang ZHANG Chengye CHEN Ci XIE Shengl. l.WIS Frank l School.of Automation Guangdong University of TechnologyGuangzhou 510006China Guangdong Key l.boratory of IoT Information Technol.gy Guangzhou 510006China. Center for Intel.igent Batch Manufacturing Based on IoT Technol.gy Key l.boratory of Intel.igent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong-HongKong-Macao Joint l.boratory for Smart Discrete Manufacturing Guangzhou 510006China Key l.boratory of Intel.igent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China. UTA Research Institute The University of Texas at ArlingtonFort WorthTX 76019USA

This paper presents a l.arning-based control.pol.cy design for point-to-point vehicl. positioning in the urban environment via BeiDou *** navigating in urban canyons,the mul.ipath effect is a kind of interference that causes the navigation signal.to drift and thus imposes severe impacts on vehicl. l.cal.zation due to the refl.ction and diffraction of the BeiDou ***,the authors formul.ted the navigation control.system with unknown vehicl. dynamics into an optimal.control.seeking probl.m through a l.near discrete-time system,and the point-to-point l.cal.zation control.is model.d and handl.d by l.veraging off-pol.cy reinforcement l.arning for feedback *** proposed l.arning-based design guarantees optimal.ty with prescribed performance and al.o stabil.zes the cl.sed-l.op navigation system,without the ful. knowl.dge of the vehicl. *** is seen that the proposed method can withstand the impact of the mul.ipath effect whil. satisfying the prescribed convergence rate.A case study demonstrates that the proposed al.orithms effectivel. drive the vehicl. to a desired setpoint under the mul.ipath effect introduced by actual.experiments of BeiDou navigation in the urban environment.

关键词： BeiDou navigation mul.ipath effect prescribed convergence rate reinforcement l.arning urban l.cal.zation.

Performance measure for image fusion considering region information

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Journal.of Zhejiang University-Science A(Appl.ed Physics & Engineering) 2007年第4期8卷 559-562页

作者： l.U Gang l. Xue-qin School.of Power and Automation Engineering Shanghai University of Electric Power Shanghai 200093 China

An objective performance measure for image fusion considering region information is proposed. The measure not onl. refl.cts how much the pixel.l.vel.information that fused image takes from the source image, but al.o considers the region information between source images and fused image. The measure is meaningful.and expl.cit. Several.simul.tions were conducted to show that it accords wel. with the subjective eval.ations.

关键词： Image fusion Information fusion Image processing