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Chinese Chemical Letters 2024年第7期35卷 264-270页

作者： yan-bo li Yi li liang Yin CAS Key Laboratory of Synthetic Chemistry of Natural Substances Centre for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

A copper(Ⅰ)-catalyzed diastereodivergent addition of phosphinothioates(HP(S)ROR')toα,β-unsaturated thioamides is disclosed,which constructs vicinal P-chiral and C-chiral centers in generally high diastereoand *** this reaction,the kinetic resolution of HP(S)ROR'occurs,which affords(R)-HP(S)Ph OMe in high enantioselectivity in the addition with(R,R)-Ph-BPE as the *** is found through control experiment that dual“soft-soft”interaction,indicated by both1H and31P NMR experiments,is indispensable in the present *** first“soft-soft”interaction between copper(Ⅰ)catalyst and HP(S)ROR'enables facile deprotonation to generate nucleophilic[Cu]-SPROR'*** second one between the[Cu]-SPROR'species andα,β-unsaturated thioamides facilitated the nucleophilic ***,both Michael adducts and(R)-HP(S)PhOMe are easily converted to synthetically useful compounds.

关键词： Copper catalysis Asymmetric catalysis Diastereodivergent synthesis P-Chirality "Soft-soft"interaction

Efficacy of physiological seawater nasal irrigation for the treatment of children with SARS-CoV-2 Omicron BA.2 variant infection:a randomized controlled trial

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World Journal of Pediatrics 2024年第5期20卷 461-469页

作者： Ji-Lei lin Fen Zhang yan-bo li Shu-Hua Yuan Jin-Hong Wu Jing Zhang Lei Zhang Yi He Jie Chen Yong Yin Department of Respiratory Medicine Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dongfang RoadPudong DistrictShanghaiChina University of British Columbia VancouverCanada Information Technology Department Shanghai Children’s Medical Center National Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dongfang RoadPudong DistrictShanghaiChina Department of Otorhinolaryngology Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dongfang RoadPudong DistrictShanghaiChina Department of Respiratory Medicine Sanya Women and Children’s Hospital Affiliated to Hainan Medical CollegeHainan Branch of Shanghai Children’s Medical CenterSanyaChina Department of Respiratory Medicine Linyi Maternal and Child Healthcare HospitalLinyiChina Shanghai Children’s Medical Center Pediatric Medical Complex(Pudong) ShanghaiChina Pediatric AI Clinical Application and Research Center Shanghai Children’s Medical CenterShanghaiChina

Background Saline nasal irrigation is an effective therapy for relieving common cold *** study aimed to investigate and explore the efficacy of physiological seawater nasal irrigation(PSNI)on children with mild and asymptomatic infection with *** This randomized controlled trial was conducted in Shanghai,China,and 403 children with mild and asymptomatic infection with Omicron were *** children were allocated into the PSNI group and the control *** primary outcome was the duration of viral shedding(DVS),and the secondary outcome was the change in clinical *** The median age of all participants was 5.59(6.26)years *** DVS was significantly shorter in the PSNI group[2.40(1.13)]than in the control group[3.09(2.14)](P=0.014).The multivariable Cox regression model also showed that patients in the PSNI group had an increased probability of shorter DVS compared with patients in the control group[hazard ratio(HR),1.27;95%confidence interval(CI),1.04–1.55;P=0.017].Subgroup analysis suggested that the DVS of patients without full vaccination was significantly reduced in the PSNI *** proportions of runny nose and stuffy nose were apparently reduced in the first three days in the PSNI group or the control group,but there was no evidence showing that PSNI contributes to the benefit compared with the control *** PSNI can reduce the DVS of patients with mild and asymptomatic infection with SARS-CoV-2 Omicron BA.2 variant.

关键词： Children Duration of viral shedding Omicron Physiological seawater nasal irrigation

Preheat Compression Molding for Polyetherketoneketone: Effect of Molecular Mobility

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Chinese Journal of Polymer Science 2022年第2期40卷 175-184页

作者： Xiao-Hua Zhang Meng-Xiao Jiao Xin Wang bo-Lan li Feng Zhang yan-bo li Jing-Na Zhao He-Hua Jin Yu yang Key Laboratory of Textile Science&Technology(Ministry of Education) College of Textilesand Innovation Center for Textile Science and TechnologyDonghua UniversityShanghai201620China Advanced Materials Division Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Key Laboratory of Carbon Materials National Engineering Laboratory for Carbon Fiber TechnologyInstitute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China

Polyetherketoneketone(PEKK)is a new evolving polymeric material,and is considered as another important member of the polyaryletherketone(PAEK)family in addition to polyetheretherketone(PEEK).Hot compression molding can be used to compact and consolidate the PEKK products,where the temperature and pressure play key roles to affect the molecular mobility,entanglement and crystallization,and thus the mechanical properties of *** this study,a preheating treatment was introduced in the compression molding,and it is found that such preheating is very essential to avoid the formation of crystal FormⅡ,based on the increased chain *** dynamics simulations revealed that the molecular mobility is always suppressed when a compression is ***,by increasing the entanglement via the preheating and maintaining such entanglement in the consequent compression molding,strong and tough PEKK materials were obtained,with a negligible fraction of crystal FormⅡ.

关键词： Polyetherketoneketone Molecular mobility Compression molding Mechanical properties

Plasma-Enhanced Atomic Layer Deposition of Amorphous Ga_(2)O_(3) for Solar-Blind Photodetection

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Journal of Electronic Science and Technology 2022年第4期20卷 331-344页

作者： Ze-Yu Fan Min-Ji yang bo-Yu Fan Andraz Mavric Nadiia Pastukhova Matjaz Valant bo-lin li Kuang Feng Dong-liang liu Guang-Wei Deng Qiang Zhou yan-bo li Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054 Materials Research Laboratory University of Nova GoricaNova Gorica SI-5000 yangtza Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001

Wide-bandgap gallium oxide(Ga_(2)O_(3))is one of the most promising semiconductor materials for solar-blind(200 nm to 280 nm)*** its amorphous form,amorphous gallium oxide(a-Ga_(2)O_(3))maintains its intrinsic optoelectronic properties while can be prepared at a low growth temperature,thus it is compatible with Si integrated circuits(ICs)***,the a-Ga_(2)O_(3) film is directly deposited on pre-fabricated Au interdigital electrodes by plasma enhanced atomic layer deposition(PE-ALD)at a growth temperature of 250°*** stoichiometric a-Ga_(2)O_(3) thin film with a low defect density is achieved owing to the mild PE-ALD *** a result,the fabricated Au/a-Ga_(2)O_(3)/Au photodetector shows a fast time response,high responsivity,and excellent wavelength selectivity for solar-blind ***,an ultra-thin MgO layer is deposited by PE-ALD to passivate the Au/a-Ga_(2)O_(3)/Au interface,resulting in the responsivity of 788 A/W(under 254 nm at 10 V),a 250-nm-to-400-nm rejection ratio of 9.2×10^(3),and the rise time and the decay time of 32 ms and 6 ms,*** results demonstrate that the a-Ga_(2)O_(3) film grown by PE-ALD is a promising candidate for high-performance solar-blind photodetection and potentially can be integrated with Si ICs for commercial production.

关键词： Amorphous gallium oxide(a-Ga_(2)O_(3)) passivation layer plasma enhanced atomic layer deposition(PE-ALD) responsivity solar-blind photodetector

A Multi-Token Sector Antenna Neighbor Discovery Protocol for Directional Ad Hoc Networks

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China Communications 2024年第7期21卷 149-168页

作者： Zhang Hang li bo yan Zhongjiang yang Mao li Xinru School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China The 54th Research Institute of CETC Shijiazhuang 050081China

In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc *** central concept of our work involves maintaining multiple tokens across the *** prevent mutual interference among multi-token holders,we introduce the time and space non-interference ***,we propose a master-slave strategy between *** the master token holder(MTH)performs the neighbor discovery,it decides which 1-hop neighbor is the next MTH and which 2-hop neighbors can be the new slave token holders(STHs).Using this approach,the MTH and multiple STHs can simultaneously discover their neighbors without causing interference with each *** on this foundation,we provide a comprehensive procedure for the M-SAND *** also conduct theoretical analyses on the maximum number of STHs and the lower bound of multi-token generation ***,simulation results demonstrate the time efficiency of the M-SAND *** compared to the QSAND protocol,which uses only one token,the total neighbor discovery time is reduced by 28% when 6beams and 112 nodes are employed.

关键词： multi-token neighbor discovery SAND protocol sector antenna ad hoc network

Scenarios analysis and performance assessment of blockchain integrated in 6G scenarios

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Science China(Information Sciences) 2024年第7期67卷 5-26页

作者： bo li Guanjie CHENG Honghao GAO Xueqiang yan Shuiguang DENG College of Computer Science and Technology Zhejiang University College of Computer Science and Technology Shanghai University 2012 Lab Huawei Technologies Co. Ltd.

Emerging applications such as smart city infrastructures and virtual reality landscapes are setting rigorous benchmarks for 6G mobile networks, requiring elevated levels of confidentiality, integrity, nonrepudiation, authentication, and stringent access controls. Blockchain technology is heralded as a transformative enabler for meeting 6G standards, owing to its intrinsic attributes. However, a gap exists in the holistic investigation of blockchain's applicability in 6G realms, particularly addressing the “whether”, “when”, and“how” of its deployment. Present research trails in developing robust methodologies to gauge blockchain's efficacy within 6G use cases. Addressing this, our study introduces a novel confluence of blockchain with 6G networks, where data resides in distributed Hash tables(DHTs) while their hashes are secured in distributed ledger technology(DLT), harnessing blockchain's core strengths-immutability, traceability, and fortified security. We delineate seven specific 6G use cases poised for enhancement through blockchain integration,and scrutinize the rationale, nature, and timing of this convergence. Furthermore, we devise a comprehensive methodology for assessing blockchain's performance metrics and scalability in 6G environments. Our extensive experimental analyses evaluate the synergistic performance of this integration, revealing that the Quorum blockchain satisfactorily supports 80% of 6G scenarios. The findings suggest that, with appropriate configurations, consortium blockchains are well-equipped to fulfill the demanding performance and scalability requisites of 6G networks.

关键词： blockchain distributed ledger technology (DLT) 6G performance assessment 6G scenarios analysis transaction arrival rate

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Concrescence of maxillary second molar and impacted third molar:A case report

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World Journal of Clinical Cases 2022年第28期10卷 10286-10292页

作者： Jun Su li-Mei Shao lian-Cheng Wang li-Jia He Ya-liu Pu yan-bo li Wen-Yun Zhang Department of Stomatology 920th Hospital of the Joint Logistics Support ForceKunming 650032Yunnan ProvinceChina

BACKGROUND Morphological anomalies of teeth,including talon cusp,dens evaginatus,gemination,fusion,concrescence,root dilaceration,and taurodontism,always involve changes in the enamel,cementum and *** concrescent teeth through routine clinical examination alone is difficult,and most cases of concrescence are found accidentally during extraction.A definite preoperative diagnosis of concrescence would contribute to a better treatment plan and fewer undesirable complications CASE SUMMARY A 47-year-old woman who complained of left maxillary first molar loss for half a year presented to our department seeking treatment by dental implant *** radiography and cone-beam computed tomography(CBCT)showed an unclear boundary between the distal root of the second molar and the mesial root of the third *** teeth were extracted under local anesthesia,and a definite diagnosis of concrescence was made by histopathological *** CBCT is a useful tool for diagnosing and planning the management of tooth concrescence and may be beneficial for reducing unnecessary complications.

关键词： Concrescence Impacted tooth Concentrate growth factor Maxillary third molar Tooth anomalies Cone-beam computed tomography Case report

Injection of a Self-propelled Polymer into a Small Circular Cavity

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Chinese Journal of Polymer Science 2024年第6期42卷 886-894页

作者： Chao Wang yan-li Zhou Xiao yang Fan Wu Meng-bo Luo Department of Physics Taizhou UniversityTaizhou318000China Department of Physics Zhejiang UniversityHangzhou310027China

The injection of a polymer chain into a small circular cavity under tangential self-propelled force is studied by using Langevin dynamics *** indicate that the injection dynamics of the active polymer shows strong correlation with the polymer conformation inside the cavity depending on the polymer rigidity(k_(b)).The injection timeτvaries nonmonotonously with increasing k_(b),and reaches its minimum at k_(b)^(*).When k_(b) is small(k_(b)≪k_(b)^(*)),the polymer is nearly random coil in the cavity,and spends a long time at the final stage of the injection process due to the large repulsion between monomers inside the *** k_(b) is moderate(k_(b)∼k_(b)^(*)),the part of polymer inside the cavity forms spiral configuration under the tangential active force,and the whole polymer moves synchronously with a constant velocity during the injection process,leading to a small injection *** k_(b) is large(k_(b)≫k_(b)^(*)),the polymer is nearly straight at the initial stage of the injection process,and takes a long time to bend itself,leading to a large injection time.

关键词： Active Polymer Injection Dynamics Simulation

BaCe_(0.8)Fe_(0.1)Ni_(0.1)O_(3−δ)-impregnated Ni-GDC by phase-inversion as an anode of solid oxide fuel cells with on-cell dry methane reforming

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Journal of Advanced Ceramics 2024年第6期13卷 834-841页

作者： yanya liu Jun Luo Cheng li bo liu Dong yan Jian li lichao Jia School of Materials Science and Engineering State Key Laboratory of Materials Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074China

BaCe_(0.8)Fe_(0.1)Ni_(0.1)O_(3−δ)(BCFN)in a perovskite structure is impregnated consecutively by BCFN solution and BCFN suspension into a phase-inversion prepared NiO–Gd_(0.1)Ce_(0.9)O_(2−δ)(GDC)scaffold as an anode for solid oxide fuel cells(SOFCs)with on-cell dry reforming of methane(DRM).The whole pore surface of the scaffold is covered by small BCFN particles formed by BCFN solution impregnation;the large pores near the scaffold surface are filled by BCFN aerogels with a high specific surface area produced by BCFN suspension impregnation,which act as a catalytic layer for on-cell *** reduction,the anode consists of a Ni–GDC scaffold and BCFN particles with exsolved FeNi3 *** BCFN-impregnated Ni–GDC anode has higher electrical conductivity,electrochemical activity,and resistance to carbon deposition,with which the cell shows maximum power densities between 1.44 and 0.92 W·cm^(−2) when using H_(2) and between 1.09 and 0.50 W·cm^(−2) when using CO_(2)–CH_(4) at temperatures ranging from 750 to 600℃.A stable performance at 400 mA·cm^(−2) and 700℃is achieved using 45%CO_(2)–45%CH_(4)–10%N_(2) for more than 400 h without carbon deposition,benefiting from the impregnated BCFN aerogel with a high specific surface area and water adsorbability.

关键词： aerogel solid oxide fuel cells(SOFCs) phase-inversion dry reforming of methane(DRM) carbon resistance

Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research(International) 2024年第4期31卷 894-908页

作者： yan-li Xin Zhi-ying Gao bo Tian Qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter