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Trifluoromethylative homo-coupling of carbonyl compounds

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Chinese Chemical Letters 2025年第1期36卷 283-287页

作者： Xinlong Han Huiying Zeng Chao-jun li The State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGill UniversityMontrealQuebecH3A 0B8Canada

Carbonyl compounds are abundant in nature and represent a substantial portion of biomass *** significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo-coupling remains a highly intricate ***,we report an entirely novel reaction paradigm:the trifluoromethylative homo-coupling of carbonyl compounds via hydrazones,which enables the formation of three C(sp^(3))-C(sp^(3))bonds in a single *** method provides a new pathway for synthesizing trifluoromethylative coupling product which has unique applications in both fields of medical and material *** investigations have unveiled that the formation of a trifluoromethyl-substituted benzyl radical plays a pivotal role as a key intermediate in this reaction.

关键词： Carbonyl compounds Trifluoromethylation Homo-coupling C(sp^(3))-C(sp^(3))bond formation

Failure mechanisms of AlGaN/GaN HEMTs irradiated by high-energy heavy ions with and without bias

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Nuclear Science and Techniques 2025年第1期36卷 49-58页

作者： Pei-Pei Hu li-jun Xu Sheng-Xia Zhang Peng-Fei Zhai ling Lv Xiao-Yu Yan Zong-Zhen li Yan-Rong Cao Xue-Feng Zheng jian Zeng Yuan He Jie liu Institute of Modern Physics Chinese Academy of Sciences(CAS)Lanzhou 730000China Key Laboratory of Wide Band‑gap Semiconductor Materials Ministry of EducationXidian UniversityXi’an 710071China University of Chinese Academy of Sciences(UCAS) Beijing 100049China

Gallium nitride(GaN)-based devices have significant potential for space ***,the mechanisms of radiation damage to the device,particularly from strong ionizing radiation,remains *** study investigates the effects of radiation on p-gate AlGaN/GaN high-electron-mobility transistors(HEMTs).Under a high voltage,the HEMT leakage current increased sharply and was accompanied by a rapid increase in power density that caused"thermal burnout"of the *** addition,a burnout signature appeared on the surface of the burned devices,proving that a single-event burnout effect ***,degradation,including an increase in the on-resistance and a decrease in the breakdown voltage,was observed in devices irradiated with high-energy heavy ions and without *** latent tracks induced by heavy ions penetrated the heterojunction interface and extended into the GaN ***,a new type of N_(2)bubble defect was discovered inside the tracks using Fresnel *** accumulation of N_(2)bubbles in the heterojunction and buffer layers is more likely to cause leakage and *** study indicates that electrical stress accelerates the failure rate and that improving heat dissipation is an effective reinforcement method for GaN-based devices.

关键词： GaN HEMTs Heavy ions Single-event burnout Latent tracks Degradation

Charged Amino Acid Frequencies of Proteins over Macroevolutionary Time Scale

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Engineering（科研） 2013年第10期5卷 420-423页

作者： Yu-Juan Zhang jian-jun li You-Jin Hao Bin Chen Art and Sciences Division Chengdu College University of Electronic Science and Technology of China Chengdu China College of life Sciences Chongqing Normal University Chongqing China

Charged amino acids (AAs) are targets for selective forces in protein evolution. To fully explore the trend of charged AA frequencies evolution in macroevolutionary process from prokaryotes to eukaryotes, we extend the analysis of five charged AAs separately and total basic and acidic AAs in protein sequences of 158 prokaryotic and 63 eukaryotic predicted proteomes and 456 clusters of orthologous groups (COGs). Also, we eliminate the biases that may caused by extreme organisms in both predicted proteomes and COGs analyses. More basic AAs, His,Lysand Glu were found in eukaryotic proteins compared with prokaryotic proteins by predicted proteomes analysis. By COGs analysis, we found that basic AAs andLysfrequencies are higher in eukaryotic orthologous proteins than their prokaryotic companions, while the trend of Arg frequency is the opposite. We discussed the agreements and disagreements of two analyses and gained a more credible trend of charged AAs evolution in macroevolutionary time scale.

关键词： Charged Amino Acid Evolution

Least Square Estimation for Multiple Functional linear Model with Autoregressive Errors

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 84-98页

作者： Meng WANG Ming-liang SHU jian-jun ZHOU Si-xin WU Min CHEN School of Management University of Science and Technology of ChinaHefei 230026China Academy of Mathematics and System Science Chinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory of Statistical Modeling and Data Analysis Yunnan UniversityKunming 650091China

As an extension of linear regression in functional data analysis, functional linear regression has been studied by many researchers and applied in various fields. However, in many cases, data is collected sequentially over time, for example the financial series, so it is necessary to consider the autocorrelated structure of errors in functional regression background. To this end, this paper considers a multiple functional linear model with autoregressive errors. Based on the functional principal component analysis, we apply the least square procedure to estimate the functional coefficients and autoregression coefficients. Under some regular conditions, we establish the asymptotic properties of the proposed estimators. A simulation study is conducted to investigate the finite sample performance of our estimators. A real example on China's weather data is applied to illustrate the validity of our model.

关键词： multiple functional linear model autoregressive errors principal component analysis consistency

Prevalence,risk factors and clinical features of sensory A-V pattern exotropia

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 323-329页

作者： Bin-Bin Zhu Shi-Yu Tang Xiang-jun Wang li-Cheng Fu jian-Hua Yan State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-Sen UniversityGuangzhou 510060Guangdong ProvinceChina Ophthalmology Department of Surgerythe Second People’s Hospital of FoshanFoshan 528000Guangdong ProvinceChina

AIM:To investigate the potential mechanisms of A-V pattern and evaluate the surgical outcomes used in the treatment of sensory ***:The medical records of patients with sensory A-V pattern exotropia who underwent strabismus surgery between May 2014 to june 2019 was retrospectively *** control group included sensory exotropia patients without A-V pattern and concomitant A-V pattern exotropia patients with normal vision who undergone strabismus surgery over this same time *** alignment,best corrected visual acuity,oblique muscle function,and stereopsis records were ***:Among the 843 eligible patients,91(10.79%;39 males and 52 females)had A-pattern(54,6.4%)or V-pattern(37,4.4%).Age at onset of vision impairment was 4±5y and at the time of surgery was 25±*** significant negative correlations were present between impaired visual acuity and the pre-operative exodeviation(r=-0.198,P=0.016)and patterns(r=-0.207,P=0.015).Age at surgery and exodeviation in patients with concomitant A-V pattern exotropia was significantly earlier as compared with that of sensory A-V pattern exotropia and sensory exotropia(both Plinical variables between sensory exotropia with or without A-V *** and pattern were significantly reduced in patients receiving horizontal rectus surgery with or without oblique muscle surgery(both P<0.0001).CONCLUSION:The prevalence of sensory A-V pattern exotropia in our study is 10.79%.Visual acuity represents an important factor contributing to the occurrence and development of A-V *** horizontal rectus surgery can provide a good option for the correction of sensory A-V pattern exotropia.

关键词： sensory exotropia A-V pattern oblique muscle dysfunction horizontal rectus surgery

Turbulent Agglomeration of Microparticles in a Cylinder Wake Flow Using LES-DEM:Focusing on the Effect of the Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 34-49页

作者： WANG Shuang MU lin li Xue XIE jun DONG Ming School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China School of Optical Information and Energy Engineering Wuhan Institute of TechnologyWuhan 430205China School of Energy and Environment Shenyang Aerospace UniversityShenyang 110136China

Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method(LES-DEM)*** validity of the LES approach was verified by comparison with available direct numerical simulation(DNS)*** adopted the Johnson-Kendall-Roberts(JKR)contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters(d_(p)=2-20μm)in the laminar and transition of shear layer(TrSL)flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise(y-direction).With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.

关键词： microparticle particle agglomeration discrete element method large eddy simulation

Spin freezing induced giant exchange bias in a doped Hund's metal

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 167-174页

作者： Shunjiao li Dan Zhao jian li Baolei Kang Min Shan Yanbing Zhou Xuyang li Tao Wu Xianhui Chen Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Strongly Coupled Quantum Matter Physics Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Superconducting Electronics(CENSE) Shanghai 200050China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Exchange bias(EB)is a fundamental phenomenon in widespread information ***,a comprehensive understanding of its microscopic origin remains a great *** key issue in the debate is the role of frustration and disorder in the EB mechanism,which motivates the exploration of the EB effect in spin glass(SG)***,in the SG state of Crdoped Hund's metal CsFe_(2)As_(2),we discover a giant EB effect with a maximum bias field of -2 T,which is almost two orders of magnitude larger than that of traditional alloy *** results indicate that the giant EB effect should originate from the exchange interactions at the natural boundaries between the tunable ferromagnetic-like(FM)regions around Cr dopants and the SG matrix,via which the FM spins are strongly pinned by the frozen spins in the SG *** addition,the temperaturedependent and cooling-field-dependent EB behaviors could be interpreted well by the SG model with frustrated FM/SG boundaries,which provides an intuitive and explicit understanding of the impact of glassy parameters on the EB *** these results suggest that the correlated metals are promising directions for exploring the EB effect in the SG state.

关键词： Hund's metal spin glass exchange bias iron-based superconductor

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Primary intestinal non-Hodgkin's lymphoma:A clinicopathologic analysis of 81 patients

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World Journal of Gastroenterology 2011年第41期17卷 4625-4631页

作者： Guo-Bao Wang Guo-liang Xu Guang-Yu Luo Hong-Bo Shan Yin li Xiao-Yan Gao jian-jun li Rong Zhang Department of Laser Treatment and Endoscopy Sun Yat-Sen University Cancer Center Guangzhou 510060 Guangdong ProvinceChina State Key Laboratory of On-cology in South China Guangzhou 510060 Guangdong Province China

AIM:To analyze the clinicopathologic features and the prognosis of primary intestinal ***:Patients were included in the study based on standard diagnostic criteria for primary gastrointesti-nal lymphoma,and were treated at Sun Yat-sen Univer-sity Cancer Centre between 1993 and ***:The study comprised 81 *** most common site was the ileocaecal ***-two point two percent patients had low-grade B-cell ***-one point nine percent patients had high-grade B-cell lymphoma and 25.9% patients had T-cell *** patients had localized *** were more patients and more early stage diseases in the latter period,and the origin sites *** ma-jority of patients received the combined treatment,andabout 20% patients only received nonsurgical *** wverall survival and event-free survival rates after 5 years were 71.6% and 60.9% *** mul-tivariate analysis revealed that small intestine and ileo-caecal region localization,B-cell phenotype,and normal lactate dehydrogenase were independent prognostic factors for better patient *** based treat-ment did not improve the survival ***:Refined stratification of the patients according to the prognostic variables may allow indi-vidualized *** treatment may be an optimal therapeutic modality for selected patients.

关键词： Gastrointestinal lymphoma Non-Hodgkin'slymphoma Gastrointestinal oncology Prognostic factors

The Teleconnection between Rainfall over the Northeastern Slope of the Tibetan Plateau and Downstream Regions:Insights from 20 Years of Heavy Rainfall Events

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Advances in Atmospheric Sciences 2025年第2期42卷 327-341页

作者： Wei SUN Rucong YU jian li Zewen li State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Tibetan Plateau Meteorology China Meteorological AdministrationChengdu 610072China Department of Atmospheric Science Yunnan UniversityKunming 650091China Inner Mongolia Autonomous Region Mete-orological Service Center Hohhot 010051China

The connection between rainfall over topographic regions and their downstream areas represents a phenomenon of great concern in atmospheric *** on the rainfall events of the past two decades,we analyzed the impact of rainfall over the Northeastern Slope of the Tibetan Plateau(NSTP)on rainfall in downstream *** discovered that rainfall followed two propagation routes,guided by two modes related to the three-dimensional circulation *** the first mode,dominated by cold(warm)anomalies along the west(east)direction,rainfall over the NSTP was concentrated between an upstream cyclonic and a downstream anti-cyclonic anomalous circulation(an upstream trough and a downstream ridge).This pattern was accompanied by upper-level divergence,low-level convergence,a deep moist layer,and a vertical *** a consequence of the eastward movement of the trough-ridge system associated with the coldwarm anomalies,the rainfall over the NSTP moved eastward along 37°-40°N,reaching North China after about 36 *** the second mode,the circulation structure was also dominated by cold-warm anomalies but rotated clockwise,introducing cold anomalies to the northeast and warm anomalies to the east of the *** the southeastward movement of the circulation structure,rainfall concentrated upstream of the anti-cyclonic circulation around the warm center before moving southeastward to the Sichuan Basin along the eastern edge of the plateau after 30-36 *** findings of this study could broaden the understanding of rainfall-related teleconnection between two distant regions and offer helpful guidance for identifying early signals of rainfall disasters over the Chinese mainland.

关键词： teleconnection rainfall propagation three-dimensional circulation structure upper-tropospheric temperature anomaly