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Resonance and Antiresonance in Electronic Transport Process Through a T-Shaped Quantum Waveguide

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Communications in Theoretical Physics 2008年第4期49卷 1039-1044页

作者： GAO wen-Zhu ZHENG yi-Song GONG Wei-Jiang SUN Lang Department of Physics Jilin University Changchun 130023 China

By means of the transfer matrix approach, the linear conductance spectrum for electronic transport through a T-shaped quantum waveguide is calculated. The resonant peaks and the antiresonant dips in the conductance spectrum are mainly focused. The previous prediction about their positions by other theoretical approaches is checked. In addition, a function of spin filtering is suggested based on the interplay of the resonance and antiresonance in this T-shaped quantum waveguide.

关键词： transfer matrix method linear conductance spectrum electronic transport quantum waveguide

Optimal resource allocation scheme for cognitive radio networks with relay selection based on game theory

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The Journal of China Universities of Posts and Telecommunications 2012年第6期19卷 25-28,62页

作者： ZHAI Lan-jie JI Hong LI Xi TANG yi-wen School of Information and Communication Engineering Beijing University of Posts and Telecommunications

In this paper, we present a non-transferable utility coalition graph game （NTU-CGG） based resource allocation scheme with relay selection for a downlink orthogonal frequency division multiplexing （OFDMA） based cognitive radio networks to maximize both system throughput and system faimess. In this algorithm, with the assistance of others SUs, SUs with less available channels to improve their throughput and fairness by forming a directed tree graph according to spectrum availability and traffic demands of SUs. So this scheme can effectively exploit both space and frequency diversity of the system. Performance results show that, NTU-CGG significantly improves system faimess level while not reducing the throughput comparing with other existing algorithms.

关键词： cooperative relaying cognitive radio networks relay selection and resource allocation coalition graph game

Technology Dependency of TID Response for a Custom Bandgap Voltage Reference in 65 nm to 28 nm Bulk CMOS Technologies

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Chinese Journal of Electronics 2023年第6期32卷 1286-1292页

作者： LIANG Bin wen yi CHEN Jianjun CHI Yaqing YAO Xiaohu College of Computer Science National University of Defense Technology

Total ionizing dose(TID) radiation response of the custom bandgap voltage reference(BGR)fabricated with 65 nm, 40 nm and 28 nm commercial bulk CMOS technologies is investigated. TID response is assessed employing Co-60 gamma ray source. The measurements indicate that the voltage reference is reduced by5.67% in 28 nm, 0.56% in 40 nm and increased by 1.28% in65 nm devices under irradiation up to 1.2 Mrad(Si) *** 48 hours of annealing, the voltage reference changes are just-1.84% in 28 nm, 0.14% in 40 nm and 1.14% in 65nm. The obtained results demonstrate that the custom BGR has naturally superior TID response due to the circuit design margins.

关键词： Voltage measurement Annealing Photonic band gap Gamma-rays Aerospace electronics CMOS technology Circuit synthesis

Insights into influence of aging processes on zero-valent iron modified biochar in copper(II) immobilization: from batch solution to pilot-scale investigation

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Frontiers of Chemical Science and Engineering 2023年第7期17卷 880-892页

作者： Huabin Wang Dingxiang Chen yi wen Ting Cui ying Liu Yong Zhang Rui Xu School of Energy and Environment Science Yunnan Normal UniversityKunming 650500China Yunnan Key Laboratory of Rural Energy Engineering Kunming 650500China

The zero-valent iron modified biochar materials are widely employed for heavy metals ***,these materials would be inevitably aged by natural forces after entering into the environment,while there are seldom studies reported the aging effects of zero-valent iron modified *** this work,the hydrogen peroxide and hydrochloric acid solution were applied to simulate aging conditions of zero-valent iron modified *** to the results,the adsorption capacity of copper(II)contaminants on biochar,zero-valent iron modified biochar-1,and zero-valent iron modified biochar-2 after aging was decreased by 15.36%,22.65%and 23.26%,*** surface interactions were assigned with chemisorption occurred on multi-molecular layers,which were proved by the pseudo-second-order and Langmuir *** aging,the decreasing of capacity could be mainly attributed to the inhibition of ion-exchange and zero-valent iron ***,the plant growth and soil leaching experiments also proved the effects of aging treatment,the zero-valent iron modified biochar reduced the inhibition of copper(II)bioavailability and increased the mobility of copper(II)after *** these results bridged the gaps between bio-adsorbents customization and their environmental behaviors during practical agro-industrial application.

关键词： zero-valent iron modified biochar aging processes copper removal adsorption pilot-scale experiments

Rare earth element geochemistry in soils along arid and semiarid grasslands in northern China

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Ecological Processes 2022年第1期11卷 386-399页

作者： yi‑wen Cao Xiao‑Ming Liu Chao Wang Edith Bai Nanping Wu CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China Department of Earth Marine and Environmental SciencesUniversity of North Carolina‑Chapel HillChapel HillNC 27515USA Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains School of Geographical SciencesNortheast Normal UniversityChangchun 130024China Institute of Deep‑Sea Science and Engineering Chinese Academy of SciencesSanya 572000China

Background:Rare earth elements(REE)are a group of trace elements that behave geochemically *** fractionation patterns normalized to reference materials provide a powerful tool for documenting *** processes are particularly difficult to illustrate with respect to contemporary and past climate *** this study,we characterize the rare earth element(REE)contents in bulk soils and respective geochemical fractions(e.g.,exchangeable,carbonate‑bound,reducible,and oxidizable fractions)and to decipher the relationships between REE geochemistry components and climatic factors across a large‑scale northern China transect(NCT).Results:Across the NCT,bulk REE concentrations ranged from 55.2 to 241.1μg g^(−1)with a main portion in the residual fraction(49–79%),followed by oxidizable fraction(2–40%),reducible fraction(3–22%),carbonate‑bound fraction(0.1–16%),and negligible exchangeable *** REE contents of geochemical components(carbonate‑bound,reducible,and oxidizable)in topsoils correlated to climate factors(mean annual precipitation,mean annual temperature,potential evaporation,and aridity index(AI)).The normalized abundances to the upper continental crust(UCC)composition show that the middle REE was generally enriched than the light REE and heavy REE in topsoils along the *** overall UCC‑normalized bulk REE patterns in topsoils and subsoils were similar,characterized by weak negative Ce anomalies and positive Eu ***:Our data in topsoils and depth profiles collectively suggest that cycling of REE was primarily regulated by abiotic processes in area with AI*** similar UCC normalized patterns in topsoils suggest that the REE was originated from a common source with limited influences from other sources(e.g.,atmospheric dusts and anthropogenic contribu‑tions).Our results to some extent provide evidence for

关键词： Rare earth elements Soil Grassland Northern China Aridity index

Luminescent Tetra-nuclear Lanthanide-titanium-organic Compound Obtained by the Mixed-ligand

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Chinese Journal of Structural Chemistry 2021年第12期40卷 1668-1672,1555页

作者： CHEN Bing-Ben ZHAO wen-Zhuo CHEN Zi-Bin wen yi-Hang CHENG Jian-wen Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhuaZhejiang 321004China

A new heterometallic lanthanide-titanium-organic compound:[Eu_(2)Ti_(2)(dip)_(6)(dig)_(2)(H_(3)0)_(2)].solvent(1,dip=diphenylglycolic acid,dig=diglycolic acid)has been synthesized under solvothermal *** 1 contains a tetra-nuclear{Eu_(2)Ti_(2)}unit with the mixed ligands of dip and *** 1 displays intense red ***,the IR,PXRD,UV-vis and TGA spectra were also studied.

关键词： lanthanide titanium luminescence

Effect of electromagnetic parameters on melt flow and heat transfer of AZ80 Mg alloy during differential phase electromagnetic DC casting based on numerical simulation

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China Foundry 2022年第3期19卷 191-200页

作者： Yong-hui Jia Cheng-lu Hu Qi-chi Le wen-yi Hu Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Longyan University College of Chemistry and Materials ScienceLongyan 364012FujianChina

Based on multi-physical field coupling numerical simulation method,magnetic field distribution,melt flow,and heat transfer behavior of aΦ300 mm AZ80 alloy billet during differential phase electromagnetic DC casting(DP-EMC)with different electromagnetic parameters were *** results demonstrate that the increase in current intensity only changes the magnitude but does not change the Lorentz force's distribution *** maximum value of the Lorentz force increases linearly followed by an increase in current *** the frequency increases,the Lorentz force's r component remains constant,and the z component decreases *** change in current intensity correlates with the melt oscillation and convection intensity positively,as well as the liquid sump temperature *** does not mean that the higher the electric current,the better the metallurgical quality of the billet.A lower frequency is beneficial to generate a more significant melt flow and velocity fluctuation,which is helpful to create a more uniform temperature *** DP-EMC parameters for aΦ300 mm AZ80 Mg alloy are 10-20 Hz frequency and 80-100 A current intensity.

关键词： heat transfer melt flow differential phase electromagnetic field DC casting Mg alloy

Epidemiology and region-specific risk factors for low Apgar scores in China:a nationwide study

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World Journal of Pediatrics 2022年第2期18卷 135-141页

作者： yi-wen Wang Yan Chen Yan-Hong Ming Jin-wen Zhang Kun Sun Jun Zhang Yong-Jun Zhang Department of Neonatology Xinhua HospitalShanghai Jiao Tong University School of Medicine1665 Kongjiang RoadShanghai 200092China Department of Obstetrics and Gynecology Hospital of Obstetrics and GynecologyFudan UniversityShanghaiChina Shanghai Key Laboratory of Embryo Original Diseases The International Peace Maternity&Child Health HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Pediatrics Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Ministry of Educaticn-Shanghai Key Laboratory of Children's Env ironmental Health Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

Background Neonatal asphyxia is a serious public health *** study aimed to determine the epidemiology and region-specific risk factors for low Apgar scores,an important proxy for neonatal asphyxia,in China from 2015 to *** The China Labor and Delivery Survey was a multicenter cross-sectional study including 96 hospitals distributed in 24(out of 34)*** regression analysis was performed to examine the risk factors for a low Apgar score(<7).Correspondence analyses were performed among neonates with low Apgar scores to explore the relationship between risk factors and geographical *** population attributable risk percentage(PAR%)was calculated for each region-specific risk *** A total of 72,073 live births,including 320 births with low Apgar scores,were used for the analysis,giving a weighted rate of 3.9/1000 live *** was a substantial difference in the incidence of low Apgar scores by geographic region,from 2.3/1000 live births in East China to 10.9/1000 live births in Northeast *** and obstetric factors are the major region-specific risk *** Southwest China,hypertensive disorders in pregnancy were more important contributors,with PAR% being 74.47%;in North and Northwest China,pre-pregnancy underweight was a more significant factor,with PAR% of 62.92%;in East China,infants born between 0:00 *** 7:59 *** a key factor,with PAR% of 80.44%.Conclusion Strategies based on region-specific risk factors should be considered to reduce the burden of low Apgar scores in China.

关键词： Apgar score China Epidemiology Risk factor

Synthesis, Structure and Aggregationinduced Emission Characteristics of Two Diaryquioxaline Derivatives

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Chinese Journal of Structural Chemistry 2019年第7期38卷 1200-1206页

作者： XIAO Xun-Li LI Fen-Fen XIAO Xun-wen wen yi-Hang Affiliated Hospital of Jinggangshan University Ji'An 343000 China Zhejiang Key Laboratory for Reactive Chemistry On Solid Surfaces Institute of Physical Chemistry Zhejiang Normal University Jinhua 321004 China Department of Material Science and Chemical Engineering Ningbo University of Technology 201 Fenghua Road Ningbo 315211 China

Two new diaryquioxaline derivatives, C21H10N2S3Br2（1） and C21H10Br2 N2OS2（2）,have been successfully synthesized. These two compounds have been determined by single-crystal X-ray diffraction analyses. Compound 1 crystallizes in monoclinic system, space group P21/n with a = 12.7896（3）, b = 6.0613（2）, c = 26.1153（7） ?, β = 94.1810（10）°, V = 2018.（97） ?3, Z = 4,C21H10N2S3Br2, Mr = 546.32, Dc = 1.797 g/cm3 and F（000） = 1072. The final R = 0.0343 and wR =0.785 for 3585 observed reflections with I > 2σ（I）. Compound 2 crystallizes in monoclinic system,space group P21/n with a = 7.8638（4）, b = 14.3447（7）, c = 17.8936（8） ?, β = 96.6980（10）°, V =2004.69（17） ?3, Z = 4, C21H10Br2 N2OS2, Mr = 530.25, Dc = 1.757 g/cm3 and F（000） = 1040. The final R = 0.0988 and wR = 0.1108 for 4613 observed reflections with I > 2σ（I）. By combination of diarylquinoxaline core and a 1,3-dithiole-2-thione unit, compound 1 is used as "turn on"chemosensors for Hg2+ by making use of the aggregation-induced emission（AIE） feature of diarylquinoxaline core and the specific reaction of 1,3-dithiole-2-thione with Hg2+.

关键词： diaryquioxaline derivatives crystal structure aggregation-induced emission