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Science China Chemistry 2023年第10期66卷 2810-2816页

作者： jian Zhang jia-yi su Yang-Zi Liu Hao Li Quannan Wang Wei-Ping Deng College of Chemistry and Materials Science Zhejiang Normal UniversityJinhua 321004China School of Pharmacy East China University of Science and TechnologyShanghai 200237China

Palladium-catalyzed allylic alkylation enabled by ketone umpolung via Pudovik addition/[1,2]-phospha-Brook rearrangement with phosphites has been *** protocol offers a straightforward method for the synthesis of potentially bioactive homoallylic alcohol phosphonates in an efficient and economical *** cascade reaction proceeds under mild conditions with excellent functional group ***,the catalytic asymmetric version has also been explored.

关键词： palladium umpolung allylic alkylation Pudovik addition -phospha-Brook rearrangement

Transition-metal-catalyzed aromatic C–H functionalization assisted by the phosphorus-containing directing groups

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Green Synthesis and Catalysis 2023年第3期4卷 206-225页

作者： jian Zhang Lingyun Yao jia-yi su Yang-Zi Liu Quannan Wang Wei Ping Deng College of Chemistry Zhejiang Normal UniversityJinhua 321004China School of Pharmacy East China University of Science and TechnologyShanghai 200237China

Transition-metal-catalyzed C–H bond functionalization has attracted tremendous attention as an increasingly important protocol for the construction of C–C and C–X *** particular,C–H bond functionalization assisted by the phosphorus-containing directing groups has made significant progress in the past few years.A series of valuable phosphorous compounds,especially phosphine ligands have been provided *** review comprehensively describes recent advances in transition-metal-catalyzed C–H bond functionalization assisted by the phosphorus-containing directing groups,highlights its potential applications in organic synthesis,and gives some insights into future advances.

关键词： Transition-metal-catalysis C-H Functionalization Phosphorus Directing group Organic synthesis

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基于ANSYS的拉丝机塔轮轴的有限元分析

塑性工程学报 2014年第6期21卷 135-141页

作者：徐杨宋仁伯贾翼速北京科技大学材料科学与工程学院北京100083

利用ANSYS对拉丝机塔轮轴进行模拟,分析塔轮轴在4种拉拔工艺下钢丝对轴的径向力、扭矩等交变载荷下的变形、应力场等,并对断口进行失效分析。结果表明,在拉丝机的4种拉拔工艺中,塔轮轴的总体形变从第二阶梯轴开始,最大变形量出现在挡板... 详细信息

利用ANSYS对拉丝机塔轮轴进行模拟,分析塔轮轴在4种拉拔工艺下钢丝对轴的径向力、扭矩等交变载荷下的变形、应力场等,并对断口进行失效分析。结果表明,在拉丝机的4种拉拔工艺中,塔轮轴的总体形变从第二阶梯轴开始,最大变形量出现在挡板前端。塔轮轴的最大变形量1.24mm,最大等效应力336.75MPa,最大等效应变1.67×10-3,最小疲劳寿命2.29年。疲劳敏感曲线随加载历程的变化趋势依次为微变,骤减,趋于稳定。第二与第三阶梯轴的轴肩处受到大小相等、方向相反的载荷作用,使载荷之间的截面发生相对错动,形成剪切形变。塔轮轴的等效应力、应变的峰值集中于轴肩处。塔轮轴失效属于疲劳断裂。塔轮轴在交变载荷下,出现滑移带、挤出脊和夹杂物开裂现象,裂纹核成为微裂纹源,扩展为宏观裂纹,最终达到断裂极限,发生断裂。

关键词：塔轮轴有限元模拟总体变形应力应变疲劳分析

0Cr13铁素体不锈钢丝在模压过程中开裂的原因

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机械工程材料 2015年第11期39卷 106-110页

作者：徐杨宋仁伯王宾宁贾翼速北京科技大学材料科学与工程学院北京100083

通过对0Cr13铁素体不锈钢丝的化学成分、显微组织、开裂形貌及夹杂物的分布等进行分析,以找到其在模压过程中发生开裂的原因。结果表明：该不锈钢丝的化学成分异常,碳含量较高,铬、锰含量较低;不锈钢丝中存在数量较多的碳化物和聚集分... 详细信息

通过对0Cr13铁素体不锈钢丝的化学成分、显微组织、开裂形貌及夹杂物的分布等进行分析,以找到其在模压过程中发生开裂的原因。结果表明：该不锈钢丝的化学成分异常,碳含量较高,铬、锰含量较低;不锈钢丝中存在数量较多的碳化物和聚集分布的夹杂物,碳化物的尺寸为0.3~0.8μm,呈暗灰色颗粒状,夹杂物的尺寸为15~25μm,主要为氧化物、钙镁酸盐及硅酸盐;模压前,不锈钢丝已发生强烈的塑性变形,碳化物在晶界处塞积,组织不均匀,夹杂物与基体的交界处存在应力集中;模压过程中,材料发生塑性失稳,裂纹起源于夹杂物导致的应力集中区域,并向内部扩展,最终导致不锈钢丝发生开裂。

关键词： 0Cr13不锈钢丝模压开裂夹杂物应力集中

Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： yi Wang Yuning Li Yakun Gu Wei Ma Yuying Guan Mengyuan Guo Qianqian Shao Xunming Ji jia Liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

Porous Organic Cage‑Based Quasi‑Solid‑State Electrolyte with Cavity‑Induced Anion‑Trapping Effect for Long‑Life Lithium Metal Batteries

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Nano-Micro Letters 2025年第2期17卷 376-386页

作者： Wei-Min Qin Zhongliang Li Wen‑Xia su jia‑Min Hu Hanqin Zou Zhixuan Wu Zhiqin Ruan Yue‑Peng Cai Kang Li Qifeng Zheng School of Chemistry South China Normal UniversityGuangzhou 510006People’s Republic of China Key Laboratory of Functional Metal‑Organic Compounds of Hunan Province College of Chemistry and Material ScienceHengyang Normal UniversityHengyang 421008People’s Republic of China Guangzhou Key Laboratory of Energy Conversion and Energy Storage Materials Guangzhou 510006People’s Republic of China

Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testified in a practical ***,we design and fabricate a quasi-solid-state electrolyte(QSSE)based on a POC to enable the stable operation of Li-metal batteries(LMBs).Benefiting from the ordered channels and cavity-induced anion-trapping effect of POC,the resulting POC-based QSSE exhibits a high Li+transference number of 0.67 and a high ionic conductivity of 1.25×10^(−4) S cm^(−1) with a low activation energy of 0.17 *** allow for homogeneous Li deposition and highly reversible Li plating/stripping for over 2000 *** a proof of concept,the LMB assembled with POC-based QSSE demonstrates extremely stable cycling performance with 85%capacity retention after 1000 ***,our work demonstrates the practical applicability of POC as SSEs for LMBs and could be extended to other energy-storage systems,such as Na and K batteries.

关键词： Porous organic cage Cavity-induced anion-trapping Quasi-solid-state electrolyte Homogeneous Li+flux Lithium metal battery

Janus MXene film with gradient structure for highly efficient terahertz and infrared electromagnetic absorption

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Nano Research 2025年第1期18卷 434-442页

作者： Shaodian Yang Weiqiang Huang Zhiqiang Lin Zibo Chen Rongliang Yang yi jia Xuebin Liu Rui Wang Zhiping Zeng Yougen Hu Huanjun Chen Xuchun Gui11 State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China National Key Laboratory of Materials for Integrated Circuits Shenzhen Institute of Advanced Electronic MaterialsShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China China Academy of Aerospace Science and Innovation Beijing 100176China Guangdong Province Key Laboratory of Display Material and Technology Guangzhou 510275China School of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China

Electromagnetic interference (EMI) shielding inhigh-frequency range, especially the rapidly growing terahertz(THz) frequency range, attracts increasing attention due tothe potential application of terahertz in 6G wirelesscommunication, and security inspection. However, traditionalconductive EMI films typically achieve high shieldingeffectiveness through strong reflection, which may causesecondary pollution to other devices. Here, a gradientstructure strategy was proposed to constructTi_(3)C_(2)Tx/hydroxypropyl methyl cellulose (HPMC) film, in whichthe content of Ti_(3)C_(2)Tx gradually increases along the thicknessdirection, resulting in different conductivity of the two surfaces(surface-M and surface-H) for the film. The obtained gradientfilmexhibits an EMI shielding efficiency of over 48.5 dB in theTHz range (0.2-1.6 THz) at a thickness of 40 μm. Especially,as the THz waves incident from the surface-H to the film, the absorption effectiveness reaches 48.2 dB (average absorbedpower loss up to 91.4%), and the reflection effectiveness is only 0.3 dB. In additions, the gradient-film also demonstrates ahigh absorption rate of 95.5% in the infrared band (2.5-16.7 μm). Moreover, the gradient-film exhibits an excellent tensilestress and Young’s modulus value of 173.1 MPa and 2.8 GPa, respectively. Therefore, the gradient-film proposed in thiswork, with excellent electromagnetic absorption in both THz and infrared band, provides a promising candidate for the nextgenerationEMI shielding applications.

关键词： electromagnetic interference shielding Janus film terahertz MXene

放射治疗对鼻咽癌颈部淋巴结疗效的多因素分析

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实用肿瘤杂志 2004年第2期19卷 114-116页

作者：何霞云陈佳艺环素兰复旦大学附属肿瘤医院放疗科上海200032

目的　探讨放射治疗对鼻咽癌颈部淋巴结疗效的影响因素。方法　全组 178例鼻咽癌行单纯放射治疗 ,38例采用双侧面颈联合野 ( A组 ) ,14 0例未用面颈联合野 ( B组 )。颈部 :面颈联合野组 ( A组 )先采用超分割治疗 ,后用颈前切线常规分割 ... 详细信息

目的　探讨放射治疗对鼻咽癌颈部淋巴结疗效的影响因素。方法　全组 178例鼻咽癌行单纯放射治疗 ,38例采用双侧面颈联合野 ( A组 ) ,14 0例未用面颈联合野 ( B组 )。颈部 :面颈联合野组 ( A组 )先采用超分割治疗 ,后用颈前切线常规分割 ,均采用 6 0 Co;非面颈联合野组 ( B组 )均采用常规分割 ,多为 6 0 Co颈前切线 + 180 KV X线。对各组性别、年龄、临床分期、放射野和分割方式对颈淋巴结疗效作单因素和多因素分析。结果　单、多因素分析 :仅 N分期与颈部淋巴结局部控制率有显著性意义。性别、年龄、T分期、放射野 (分割方式 )与颈部淋巴结局部控制率无明显相关。颈部超分割 +常规分割即面颈联合野组 ( A组 )和单纯常规分割即非面颈联合野组 ( B组 )的 5年颈部淋巴结局部控制率分别为 82 .7%、83.8% ,差异无显著性 ( P=0 .6 0 4 9)。结论　 N分期是影响颈部淋巴结局部控制率的重要因素。

关键词：放射治疗鼻咽癌颈部淋巴结鼻咽肿瘤放射疗法

Design and performance evaluation of a novel ranging signal based on an LEO satellite communication constellation

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Geo-Spatial Information Science 2023年第1期26卷 107-124页

作者： Jingfang su jia su Qingwu yi Cailun Wu Weimin Hou School of Information Science and Engineering Hebei University of Science and TechnologyShijiazhuangChina The State Key Laboratory of Satellite Navigation System and Equipment Technology ShijiazhuangChina

Driven by improvements in satellite internet and Low Earth Orbit(LEO)navigation augmenta-tion,the integration of communication and navigation has become increasingly common,and further improving navigation capabilities based on communication constellations has become a significant *** the context of the existing Orthogonal Frequency Division Multiplexing(OFDM)communication systems,this paper proposes a new ranging signal design method based on an LEO satellite communication *** LEO Satellite Communication Constellation Block-type Pilot(LSCC-BPR)signal is superimposed on the com-munication signal in a block-type form and occupies some of the subcarriers of the OFDM signal for transmission,thus ensuring the continuity of the ranging pilot signal in the time and frequency *** estimation in the time and frequency domains is performed to obtain the relevant distance value,and the ranging accuracy and communication resource utilization rate are *** characterize the ranging performance,the Root Mean Square Error(RMSE)is selected as an evaluation *** show that when the number of pilots is 2048 and the Signal-to-Noise Ratio(SNR)is 0 dB,the ranging accuracy can reach 0.8 m,and the pilot occupies only 50%of the communication subcarriers,thus improving the utilization of communication resources and meeting the public demand for communication and location services.

关键词： Integration of communication and navigation LEO communication constellation ranging LEO navigation augmentation satellite internet

Near-infrared brain functional characteristics of mild cognitive impairment with sleep disorders

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World Journal of Psychiatry 2025年第1期15卷 106-116页

作者： Heng Liao Sha Liao Yu-jiao Gao Xi Wang Li-Hong Guo su Zheng Wu Yang yi-Nan Dai Sleep Psychosomatic Medicine Center Taihe Hospital of Shiyan CityAffiliated Hospital of Hubei University of MedicineShiyan 442000Hubei ProvinceChina Department of Integrated Chinese and Western Medicine Taihe Hospital of Shiyan CityAffiliated Hospital of Hubei University of MedicineShiyan 442000Hubei ProvinceChina Department of Orthopaedics Taihe Hospital of Shiyan CityAffiliated Hospital of Hubei University of MedicineShiyan 442000Hubei ProvinceChina Department of Rehabilitation Taihe Hospital of Shiyan CityAffiliated Hospital of Hubei University of MedicineShiyan 442000Hubei ProvinceChina

BACKGROUND Mild cognitive impairment(MCI)has a high risk of progression to Alzheimer’s *** disease is often accompanied by sleep disorders,and whether sleep disorders have an effect on brain function in patients with MCI is *** To explore the near-infrared brain function characteristics of MCI with sleep *** A total of 120 patients with MCI(MCI group)and 50 healthy subjects(control group)were *** subjects underwent the functional near-infrared spec-troscopy *** baseline data,Mini-Mental State Examination,Montreal Cognitive Assessment scale,fatigue severity scale(FSS)score,sleep parameter,and oxyhemoglobin(Oxy-Hb)concentration and peak time of functional near-infrared spectroscopy test during the task *** relationship between Oxy-REsuLTS Compared with the control group,the FSS score of the MCI group was higher(t=11.310),and the scores of Pittsburgh sleep quality index,sleep time,sleep efficiency,nocturnal sleep disturbance,and daytime dysfunction were higher(Z=-10.518,-10.368,-9.035,-10.661,-10.088).subjective sleep quality and total sleep time scores were lower(Z=-11.592,-9.924).The sleep efficiency of the MCI group was lower,and the awakening frequency,rem sleep latency period,total sleep time,and oxygen desaturation index were higher(t=5.969,5.829,2.887,3.003,5.937).The Oxy-Hb concentration at T0,T1,and T2 in the MCI group was lower(t=14.940,11.280,5.721),and the peak time was higher(t=18.800,13.350,9.827).In MCI patients,the concentration of Oxy-Hb during T0 was negatively correlated with the scores of Pittsburgh sleep quality index,sleep time,total sleep time,and sleep efficiency(r=-0.611,-0.388,-0.563,-0.356).It was positively correlated with sleep efficiency and total sleep time(r=0.754,0.650),and negatively correlated with oxygen desaturation index(r=-0.561)and FSS score(r=-0.526).All comparisons were P<*** Patients with MCI and sleep disorders have lower near-infrared brain function than norm

关键词： Mild Cognitive impairment Sleep disorders Near-infrared Brain functional Characteristics