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Nano Research 2024年第3期17卷 1655-1665页

作者： Yuhang zhu Tingting liu lin li Maosheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics&Electron EngineeringHarbin Normal UniversityHarbin 150025China

Currently,as the electromagnetic(EM)environment becomes increasingly complex,single-function EM materials can hardly resist the increasing electromagnetic interference(EMI),and there is an urgent need to develop multifunctional EM *** this work,multifunctional WSe_(2)/Co_(3)C was prepared by simple hydrothermal *** dielectric performance and EM response were *** absorption,shielding performance,and energy conversion devices were *** tailoring the loading content,WSe_(2)/Co_(3)C can switch between EM absorption and EMI *** maximum shielding effectiveness(SE)of WSe_(2)/Co_(3)C reached 36 dB,and high reflection loss(RL)of-60.28 dB and wide effective absorption bandwidth(EAB)of 6.16 GHz can be obtained at low *** multiple EM attenuation mechanisms brought by the combination of two-dimensional(2D)WSe_(2) and magnetic Co_(3)C are considered to be the main reason for the enhanced EM attenuation *** WSe_(2)/Co_(3)C composite provides a viable candidate for developing multifunctional EM materials in 2–18 GHz.

关键词： WSe_(2) Co_(3)C electromagnetic property microwave absorption electromagnetic interference shielding energy conversion

A Comparative Study of the Power-law Relationship between the Pulse width and Energy of Precursor and Main Burst

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Research in Astronomy and Astrophysics 2024年第3期24卷 144-168页

作者： Hui-Ying Deng Zhao-Yang Peng Jia-ming Chen Dan zhu College of Physics and Electronic Information Yunnan Normal UniversityKunming 650500China

In gamma-ray burst prompt emission,there is still no consistent conclusion if the precursor and main burst share the same *** this paper,we try to study this issue based on the relationship between pulse width and energy of the precursor and main *** systematically search the light curve data observed by Swift/BAT and Fermi/GBM,and find 13 long bursts with well-structured precursors and main *** fitting the precursor light curve of each different energy channel with the Norris function,we find that there is not only a power-law relationship between precursor width and energy,but also a power-law relationship between the ratio of the rising width to the decaying width and *** comparing the relationship between the precursors and the main burst pulses,we find that the distribution of the precursors and the relationship between the power-law indices are roughly the same as those of the main *** addition,it is found that the precursor width distribution as well as the upper limit of the pulse width ratio does not exceed 1 and both are asymmetric,which are also consistent with the main *** indicate that the precursor and the main burst are indistinguishable,and the precursor and the main burst may have the same physical origin.

关键词： methods data analysis-(stars) gamma-ray burst general-shock waves

Preventing formation of intermetallic compounds in ultrasonic-assisted Sn soldering of Mg/Al alloys through pre-plating a Ni coating layer on the Mg substrate

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Journal of Magnesium and Alloys 2024年第2期12卷 726-741页

作者： Yingzong liu Yuanxing li Hui Chen Zongtao zhu Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031PR China

Magnesium and aluminum alloys are widely used in various industries because of their excellent properties,and their reliable connection may increase application of *** compounds(IMCs)affect the joint performance of Mg/*** this study,AZ31 Mg alloy with/without a nickel(Ni)coating layer and 6061 Al alloy were joined by ultrasonic-assisted soldering with Sn-3.0Ag-0.5Cu(SAC)*** effects of the Ni coating layer on the microstructure and mechanical properties of Mg/Al joints were systematically *** Ni coating layer had a significant effect on formation of the Mg_(2)Sn IMC and the mechanical properties of Mg/Al *** blocky Mg_(2)Sn IMC formed in the Mg/SAC/Al joints without a Ni coating *** content of the Mg_(2)Sn IMC increased with increasing soldering temperature,but the joint strength *** joint without a Ni coating layer fractured at the blocky Mg_(2)Sn IMC in the solder,and the maximum shear strength was 32.2 *** pre-plating Ni on the Mg substrate,formation of the blocky Mg_(2)Sn IMC was inhibited in the soldering temperature range 240–280℃and the joint strength ***,when the soldering temperature increased to 310℃,the blocky Mg_(2)Sn IMC precipitated again in the *** electron microscopy showed that some nano-sized Mg_(2)Sn IMC and the(Cu,Ni)_(6)Sn_(5)phase formed in the Mg(Ni)/SAC/Al joint soldered at 280℃,indicating that the Ni coating layer could no longer prevent diffusion of Mg into the solder when the soldering temperature was higher than 280℃.The maximum shear strength of the Mg(Ni)/SAC/Al joint was 58.2 MPa for a soldering temperature of 280℃,which was 80.7%higher than that of the Mg/SAC/Al joint,and the joint was broken at the Mg(Ni)/SAC ***-plating Ni is a feasible way to inhibit formation of IMCs when joining dissimilar metals.

关键词： Ultrasonic-assisted soldering Mg_(2)Sn Ni coating layer Shear strength

Research progress on rolling superlubricity in solid lubricants

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Science China(Technological Sciences) 2024年第7期67卷 1980-1990页

作者： li PanPan li HongXuan zhu DongXiang zhu YongQi KANG FuYan WANG Wan ZHANG YaXin liU XiaoHong JI li ZHOU HuiDi CHEN JianMin State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Chemical Engineering Northwest Minzu UniversityLanzhou 730030China

Superlubricity is an ideal lubrication state where friction nearly vanishes between contact interfaces. It has become one of the most important research topics and approaches owing to its significance in reducing energy consumption and preventing device failures. As an efficient and universal lubricating principle capable of achieving superlubricity, rolling lubrication has attracted widespread attention in recent years. In this review, the theoretical concept of rolling lubrication and the experimental research progress of spherical/scroll structures are summarized. The review focuses on the possibility of achieving rolling lubrication using spherical/scroll structures(such as spherical fullerenes, carbon nanotubes, and formed and constructed spherical/scroll structures). The challenges in achieving rolling lubrication are summarized, and the possibility of molecular rolling lubrication,as well as its potential applications in superlubrication, are discussed.

关键词： spherical/scroll structure rolling lubrication superlubricity fullerene

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Genetic analyses of ancient tea trees provide insights into the breeding history and dissemination of Chinese Assam tea(Camellia sinensis ***)

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Plant Diversity 2024年第2期46卷 229-237页

作者： Miao-Miao li Muditha K.Meegahakumbura Moses C.Wambulwa Kevin S.Burgess Michael Möller Zong-Fang Shen De-zhu li lian-ming Gao CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of ScienceKunming650201China Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of ScienceKunming650201China Kunming College of life Science University of Chinese Academy of SciencesKunming650201YunnanChina Department of Export Agriculture Faculty of Animal Science and Export AgricultureUva Wellassa UniversityBadulla90000Sri Lanka Department of life Sciences School of Science and ComputingSouth Eastern Kenya University170-90200KituiKenya Department of Biology Columbus State UniversityUniversity System of GeorgiaColumbusGA31907-5645USA Royal Botanic Garden Edinburgh 20A Inverleith RowEdinburghEH35LRScotlandUK lijiang Forest Biodiversity National Observation and Research Station Kunming Institute of BotanyChinese Academy of SciencesLijiang674100YunnanChina

Chinese Assam tea(Camellia sinensis ***)is an important tea crop with a long history of cultivation in Yunnan,*** its potential value as a genetic resource,its genetic diversity and domestication/breeding history remain *** address this issue,we genotyped 469 ancient tea plant trees representing 26 *** *** populations,plus two of its wild relatives(six and three populations of *** and ***,respectively)using 16 nuclear microsatellite *** showed that Chinese Assam tea has a relatively high,but comparatively lower gene diversity(H_(S)=0.638)than the wild relative ***(H_S=0.658).Clustering in STRUCTURE indicated that Chinese Assam tea and its two wild relatives formed distinct genetic groups,with considerable interspecific *** Chinese Assam tea accessions clustered into three gene pools,corresponding well with their geographic ***,New Hybrids analysis indicated that 68.48%of ancient Chinese Assam tea plants from Xishuangbanna were genetic intermediates between the Puer and lincang gene *** addition,10%of the ancient Chinese Assam tea individuals were found to be hybrids between Chinese Assam tea and *** results suggest that Chinese Assam tea was domesticated separately in three gene pools(Puer,lincang and Xishuangbanna)in the Mekong River valley and that the hybrids were subsequently selected during the domestication *** the domestication history of Chinese Assam tea in southwestern Yunnan remains complex,our results will help to identify valuable genetic resources that may be useful in future tea breeding programs.

关键词： Tea plant Hybrid origin Genetic diversity Domestication history Camellia sinensis var.assamica Camellia taliensis

Bifunctional two-carbon reagent made from acetylene via 1,2-difunctionalization and its applications

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Science China Chemistry 2024年第3期67卷 936-944页

作者： Bo Yang Kangkui li Yongdong Wang Shifa zhu Key Laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China School of Chemistry and Chemical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Singfar Laboratories Guangzhou 510670China

There are very limited approaches to directly gluing two molecules for the production of internal alkenes using the vastly abundant acetylene via 1,2-difunctionalization. Conversion of gaseous acetylene to internal alkenes via 1,2-difunctionalization in a desired manner is not as easy as it might be expected due to the potential competition reactions between acetylene and alkene produced and the difficulty in handling this harmful reagent and controlling the regio-and stereoselectivity. In this work, we designed an efficient catalytic system for the incorporation of acetylene gas into tremendous(E)-β-bromo vinylsulfones, which are bench-stable, easy to operate, and can function as bifunctional acetylene and show a rich reactivity profile in Sonogashira coupling, Heck coupling, substituted reaction, and various desulfonylation transformations, providing numerous internal alkenes.

关键词： acetylene 1 2-difunctionalization photocatalysis vinylsulfone

The Number of Positive Pelvic Lymph Nodes and Multiple Groups of Pelvic Lymph Node Metastasis Influence Prognosis in Stage ⅠA-ⅡB Cervical Squamous Cell Carcinoma

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Chinese Medical Journal 2015年第15期128卷 2084-2089页

作者： Yu liu li-Jon Zhao ming-Zho li ming-Xia li Jian-liu Wang li-Hui Wei Department of Obstetrics and Gynecology Peking University People's Hospital Beijing 100044 China

Background：Pelvic lymph node metastasis （LNM） is an important prognostic factor in cervical *** squamous cell carcinoma accounts for approximately 75-80% of all cervical *** of the effects of the number of positive lymph nodes （LNs）,unilateral vcrsus bilateral pelvic LNM and a single group versus multiple groups of pelvic LNM on survival and recurrence of cervical squamous cell carcinoma are still *** study aimed to analyze the effects of the number of positive pelvic LNs and a single group versus multiple groups of pelvic LNM on survival and ***：We performed a retrospective review of 296 patients diagnosed with Stage ⅠA-ⅡB cervical squamous cell carcinoma who received extensive/sub-extensive hysterectomy with pelvic lymphadenectomy/pelvic LN sampling at Peking University People＇s Hospital from November 2004 to July *** clinicopathological variables were evaluated as risk factors for pelvic LNM：Age at diagnosis,gravidity,clinical stage,histological grade,tumor diameter,lymph-vascular space involvement （LVSI）,depth of cervical stromal invasion,uterine invasion,parametrial invasion,and neoadjuvant ***：The incidence of pelvic LNM was 20.27% （60/296 cases）.Pelvic LNM （P =0.00） was significantly correlated with *** LNM （P =0.00）,the number of positive pelvic LNs （P =0.04） and a single group versus multiple groups of pelvic LNM （P =0.03）had a significant influence on *** analysis revealed that LVSI （P =0.00）,depth of cervical stromal invasion （P =0.00）and parametrial invasion （P =0.03） were independently associated with pelvic ***：Patients with pelvic LNM had a higher recurrence rate and poor survival ***,more than 2 positive pelvic LNs and multiple groups of pelvic LNM appeared to identify patients with worse survival outcomes in node-positive ⅠA-ⅡB cervical squamous cell ***,parametrial invasion,and depth of cervical stromal invas

关键词： Cervical Squamous Cell Carcinoma Pelvic Lymph Node Metastasis Prognosis

Centrifuge modeling of unreinforced and multi-row stabilizing piles reinforced landslides subjected to reservoir water level fluctuation

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1600-1614页

作者： Chenyang Zhang Yueping Yin Hui Yan Sainan zhu ming Zhang Luqi Wang Department of Civil Engineering The University of Hong KongHong KongChina China Institute of Geo-environment Monitoring BeijingChina Chongqing 107 Municipal Construction Engineering Co. Ltd.ChongqingChina Faculty of Engineering China University of GeosciencesWuhanChina School of Civil Engineering Chongqing UniversityChongqingChina

With the construction of the Three Gorges Reservoir dam,frequent reservoir landslide events have been *** recent years,multi-row stabilizing piles(MRSPs)have been used to stabilize massive reservoir landslides in *** this study,two centrifuge model tests were carried out to study the unreinforced and MRSP-reinforced slopes subjected to reservoir water level(RWL)operation,using the Taping landslide as a *** results indicate that the RWL rising can provide lateral support within the submerged zone and then produce the inward seepage force,eventually strengthening the slope ***,a rapid RWL drawdown may induce outward seepage forces and a sudden debuttressing effect,consequently reducing the effective soil normal stress and triggering partial pre-failure within the RWL fluctuation ***,partial deformation and subsequent soil structure damage generate excess pore water pressures,ultimately leading to the overall failure of the reservoir *** study also reveals that a rapid increase in the downslope driving force due to RWL drawdown significantly intensifies the lateral earth pressures exerted on the ***,the MRSPs possess a considerable reinforcement effect on the reservoir landslide,transforming the overall failure into a partial deformation and failure situated above and in front of the *** mechanical transfer behavior observed in the MRSPs demonstrates a progressive alteration in relation to RWL *** the RWL rises,the mechanical states among MRSPs exhibit a growing *** shear force transfer factor(*** ratio of shear forces on pile of the n th row to that of the first row)increases significantly with the RWL *** indicates that the mechanical states among MRSPs tend toward an enhanced *** insights gained from this study contribute to a more comprehensive understanding of the failure mechanisms of reservoir landslides and the mechanical behavior of M

关键词： Reservoir landslide Failure mechanism Multi-row stabilizing piles Mechanical behavior

Isocyanide-Based One-Pot Cascade Synthesis of 3-Acyl Isoindolinones

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Chinese Journal of Chemistry 2024年第3期42卷 259-263页

作者： Jia liu Yi-ming zhu Xiao-Ping Xu Shun-Jun Ji Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhouJiangsu215123 China Suzhou Baolidi Functional Materials Research Institute SuzhouJiangsu215144 China

A series of 3-acyl-substituted isoindolinone derivatives were synthesized in a one-pot manner via the reaction of o-bromobenzaldehydes,isocyanides,and carboxylic acids in the presence of palladium catalyst and base. The reaction employing easily available starting materials features simple operation and high efficiency. The mechanistic study showed that the reaction might undergo 1) Pd-catalyzed [3+2] cyclization of o-bromobenzaldehyde with isocyanide and the re-insertion of another molecule of isocyanide,2) addition of carboxylic acid to in situ formed ketenimine followed by a rearrangement relay to give 3,3-diacyl-substituted isoindolinone derivative. Further transformations of the obtained products through decarbonylation could also be realized.

关键词： One-pot reaction Isocyanide Pd catalysis Rearrangement reaction Isoindolinone

Tumor recurrence and survival prognosis in patients with advanced gastric cancer after radical resection with radiotherapy and chemotherapy

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1660-1669页

作者： Shuang-Fa Nie Chen-Yang Wang Lei li Cheng Yang Zi-ming zhu Jian-Dong Fei Department of General Surgery The First Affiliated Hospital of Hebei North UniversityZhangjiakou 75000Hebei ProvinceChina Department of Gastrointestinal Surgery Zhongshan Hospital of Fudan UniversityShanghai 200032China

BACKGROUND Advanced gastric cancer is a common malignancy that is often diagnosed at an advanced stage and is still at risk of recurrence after radical surgical ***,as one of the important treatment methods for gastric cancer,is of great significance for improving the survival rate of ***,the tumor recurrence and survival prognosis of gastric cancer patients after radio-therapy and chemotherapy are still *** To analyze the tumor recurrence after radical radiotherapy and chemotherapy for advanced gastric cancer and provide more in-depth guidance for *** A retrospective analysis was performed on 171 patients with gastric cancer who received postoperative adjuvant radiotherapy and chemotherapy in our hospital from 2021 to *** Kaplan-Meier method was used to calculate the recurrence rate and survival rate;the log-rank method was used to analyze the single-factor prognosis;and the Cox model was used to analyze the prognosis associated with multiple *** The median follow-up time of the whole group was 63 months,and the follow-up rate was 93.6%.Stage Ⅱ and Ⅲ patients accounted for 31.0%and 66.7%,*** incidences of Grade 3 and above acute gastrointestinal reactions and hematological adverse reactions were 8.8%and 9.9%,respectively.A total of 166 patients completed the entire chemoradiotherapy regimen,during which no adverse reaction-related deaths *** terms of the recurrence pattern,17 patients had local recurrence,29 patients had distant metastasis,and 12 patients had peritoneal implantation *** 1-year,3-year,and 5-year overall survival(OS)rates were 83.7%,66.3%,and 60.0%,*** 1-year,3-year,and 5-year disease-free survival rates were 75.5%,62.7%,and 56.5%,*** analysis revealed that T stage,peripheral nerve invasion,and the lymph node metastasis rate(LNR)were independent prognostic factors for *** Postoperative intensity-

关键词： Tumor recurrence Survival prognosis Advanced gastric cancer Radical resection Retrospective study