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TC4钛合金叶片双面同时激光斜冲击强化研究

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机械工程与自动化 2024年第3期 103-104,107页

作者：汤洋廖一凡李斯魏吴小燕张永康广东工业大学机电工程学院广东广州510006 中国航发南方工业有限公司湖南株洲412002

为了提高航空发动机叶片抗外物损伤能力,采用双面同时激光斜冲击方式对叶片前缘进行强化处理,研究双面同时激光斜冲击强化对叶片表面粗糙度、显微硬度、残余应力和变形的影响。结果表明:激光冲击后,叶片表面粗糙度由Ra0.374μm增加到了R... 详细信息

为了提高航空发动机叶片抗外物损伤能力,采用双面同时激光斜冲击方式对叶片前缘进行强化处理,研究双面同时激光斜冲击强化对叶片表面粗糙度、显微硬度、残余应力和变形的影响。结果表明:激光冲击后,叶片表面粗糙度由Ra0.374μm增加到了Ra1.582μm;叶片表面显微硬度平均值增加了50%;叶片表面残余应力均为压应力,最大残余压应力为-354.3 MPa;叶片最大变形量位于叶背面靠近叶尖的位置,变形与双面同时激光斜冲击强化在叶片前缘引入的不均匀残余应力分布密切相关。

关键词： TC4钛合金整体叶盘叶片双面同时激光斜冲击强化处理

Advancing from scalar to vectorial liquid crystal holography:a paradigm shift

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Light(Science & Applications) 2024年第9期13卷 1696-1697页

作者： yan Li Shin-Tson wu Department of Electronic Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Optics and Photonics University of Central FloridaOrlandoFL 32816USA

A versatile and tunable vectorial holography is demonstrated based on single-layer single-material liquid crystal *** novel approach advances the process from scalar to vectorial holography,opening new opportunities f... 详细信息

关键词： liquid crystal versatile

A Novel Preparation Method of C-Terminal Glutamine Dipeptides

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应用化学 2006年第1期23卷 109-112页

作者： QIAN Shao-Song LIU Yi CHEN Ran LI Jia-You wu xiao-yan JIAO Qing-Cai College of Life Science Nanjing University Nanjing 210093

A novel synthesis method of dipeptides containing glutamine is reported. Protected L-amino acids were prepared by using inexpensive phthaloyl as the protecting group. Then the phthaloyl-L-amino acids were condensed with glutamine salts by the mixed anhydride method to afford phthaloyl dipeptides. Subsequently, the phthaloyl was removed from the dipeptides with hydrazine hydrate. As a result, optically pure glutamine-containing dipeptides were obtained in good yields.

关键词：制备方法 C-谷氨酸二肽 L-丙氨酰基-L-谷氨酸盐甘氨酰基-L-谷氨酸盐混合酐

High-throughput screening of single-atom catalysts confined in monolayer black phosphorus for efficient nitrogen reduction reaction

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Nano Research 2024年第4期17卷 2360-2367页

作者： xiao-yan Li Manyi Duan Pengfei Ou Department of Electrical and Computer Engineering University of TorontoTorontoOntario M5S 1A4Canada School of Physics and Electronic Engineering Sichuan Normal UniversityChengdu 610101China Department of Chemistry Northwestern UniversityEvanstonIL 60208USA

The discovery of metal-nitrogen centers as the active sites for electrolysis has aroused significant interest in utilizing single-atom catalysts for nitrogen reduction reaction(NRR).Properly designed nanostructured catalysts that strongly interact with nitrogen molecules(N_(2))can promote adsorption and activation,thereby resulting in efficient catalysts with high stability,activity,and *** this study,using density functional theory calculations,we selected monolayer black phosphorus(BP)as the substrate and screened a series of single-atom transition metals confined in tri-coordinated and tetra-coordinated active centers(without and with N dopants)to electro-catalyze *** a result,we have identified two promising candidates(Hf_(1)-N_(1)P_(2)-1 and Tc_(1)-N_(4)),which exhibit not only low overpotentials of 0.56 and 0.49 V but also high thermodynamic and electrochemical stability,as well as good selectivity towards NRR over the competing hydrogen evolution *** also demonstrate the ability of Hf_(1)-N_(1)P_(2)-1 and Tc_(1)-N_(4) to activate and hydrogenate N_(2) by donating electrons and regulating charge *** study not only predicts new BP-based promising catalysts but also provides guidance for the rational design of high-performance NRR electrocatalysts under ambient conditions.

关键词： N_(2) electroreduction reaction single-atom catalysts black phosphorus density functional theory high-throughput calculations

Lignin-reinforced PVDF electrolyte for dendrite-free quasi-solid-state Li metal battery

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Rare Metals 2024年第3期43卷 1006-1016页

作者： Xin-yang Chen Xue-Jie Gao Han-yan wu Yu-Long Liu xiao-Fei yang Run-Cang Sun Center for Lignocellulosic Chemistry and Biomaterials College of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian116034China Division of Energy Storage Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China School of Chemistry Northeast Normal UniversityChangchun130024China

Quasi-solid-state lithium metal batteries(QSSLMBs)assembled with polyvinylidene fluoride(PVDF)are a promising class of next-generation rechargeable batteries due to their safety,high energy density,and superior interfacial ***,PVDF has a series of inherent drawbacks such as low ionic conductivity,ease of crystallization,and hydrophobic character that leading to poor cell *** tackle these issues,a lignin-reinforced PVDF electrolyte is proposed in this work to solve these drawbacks of PVDF and enhance the comprehensive performance of *** lithophilic polar groups of lignin can promote uniform deposition of Li on the *** with the improved mechanical properties can efficiently prevent Li dendrites penetration through the *** addition,more active sites provided by lignin can also enhance Li^(+)transport and lead to a faster electrochemical reaction *** from the ingenious design,Li symmetric cells with 5%lignin-PVDF quasi-solid-state electrolyte can operate for 900 h at a high current density/capacity of 5 mA·cm^(-2)/5 mAh·cm^(-2),while shortcircuiting occurs after 56 h for the counterpart(pure PVDF).Moreover,a full cell of Li/5%lignin-PVDF/LFP cell demonstrates a high capacity of 96.2 mAh·g^(-1)after 2000 cycles at 10 *** work is expected to open up promising opportunities to develop other high-energy/power-density QSSLMBs.

关键词： Quasi-solid-state electrolyte Lignin PVDF Dendrite-free Li metal battery

Transcatheter arterial chemoembolization combined with PD-1 inhibitors and Lenvatinib for hepatocellular carcinoma with portal vein tumor thrombus

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World Journal of Gastroenterology 2024年第8期30卷 843-854页

作者： Hong-xiao wu xiao-yan Ding Ya-Wen Xu Ming-Hua Yu xiao-Mi Li Na Deng Jing-Long Chen Cancer Center Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China

BACKGROUND Hepatocellular carcinoma(HCC)patients complicated with portal vein tumor thrombus(PVTT)exhibit poor prognoses and treatment *** To investigate efficacies and safety of the combination of PD-1 inhibitor,transcatheter arterial chemoembolization(TACE)and Lenvatinib in HCC subjects comorbid with *** From January 2019 to December 2020,HCC patients with PVTT types Ⅰ-Ⅳ were retrospectively enrolled at Beijing Ditan *** were distributed to either the PTL or TACE/Lenvatinib(TL)*** median progression-free survival(mPFS)was set as the primary endpoint,while parameters like median overall survival,objective response rate,disease control rate(DCR),and toxicity level served as secondary *** Forty-one eligible patients were finally recruited for this study and divided into the PTL(n=18)and TL(n=23)*** a median follow-up of 21.8 months,the DCRs were 88.9%and 60.9%in the PTL and TL groups(P=0.046),***,mPFS indicated significant improvement(HR=0.25;P<0.001)in PTL-treated patients(5.4 months)compared to TL-treated(2.7 months)*** were no treatment-related deaths or differences in adverse events in either *** A triplet regimen of PTL was safe and well-tolerated as well as exhibited favorable efficacy over the TL regimen for advanced-stage HCC patients with PVTT types Ⅰ-Ⅳ.

关键词： Hepatocellular carcinoma Transcatheter arterial chemoembolization Lenvatinib PD-1 inhibitor Portal vein tumor thrombus

Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： yan Yu yang Li Yu Liu xiao-xiao Ling Li-Guang wu Li yang Lan yang Bo yang Yong-Gang Zhao Xian-Hua Li State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

Martensitic transformation pathways and crystallographic orientation relationships in steel

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Journal of Materials Science & Technology 2024年第7期174卷 74-84页

作者： Tian-Wei Liu xiao-Lei wu State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Martensite is one of the most important structures determining the ability to tailor the performance of steel and several other engineering *** previous studies,the face-centered cubic(FCC)to hexag-onal close-packed(HCP)(or body-centered cubic(BCC))martensitic transformation and the FCC to body-centered tetragonal(BCT)(or BCC)martensitic transformation during deformation and quenching were widely investigated;these transformations usually improve the plasticity and strength of steel,*** this work,detailed transmission electron microscopy(TEM)observations and electron diffraction pattern analyses of the BCT and BCC twins are performed along the[110],[131],and[¯153]zone *** transformation of BCT twins into BCC twins along the[131]zone axis is also analyzed through in situ heating during the TEM *** high-resolution TEM observations of mutually perpendicular BCT variants are consistent with the atomic arrangement obtained for the quenching pathway during the martensitic *** addition,different orientation relationships between austenite and marten-site are explained in terms of the atomic migration occurring during the deformation pathway and the quenching pathway of the martensitic transformation.

关键词： Body-centered tetragonal twin Martensitic transformation Steel Transmission electron microscopy Orientation relationship

不同剂量阿加曲班联合丁苯酞对急性脑梗死患者效果及预后的影响因素分析

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现代生物医学进展 2024年第12期24卷 2279-2283页

作者：张龙吴小燕高金玉李群杨国强葛纪刘赟中国人民解放军陆军第七十一集团军医院神经内科江苏徐州221000

目的:本研究旨在探讨不同剂量阿加曲班联合丁苯酞对急性脑梗死患者效果及预后的影响因素。方法:以自2019年6月到2022年8月在我院收治的90例急诊急性脑梗死为研究对象,采用随机数字表法将其分为高剂量组(给予高剂量阿加曲班联合丁苯酞治... 详细信息

目的:本研究旨在探讨不同剂量阿加曲班联合丁苯酞对急性脑梗死患者效果及预后的影响因素。方法:以自2019年6月到2022年8月在我院收治的90例急诊急性脑梗死为研究对象,采用随机数字表法将其分为高剂量组(给予高剂量阿加曲班联合丁苯酞治疗)和低剂量组(给予低剂量阿加曲班联合丁苯酞治疗)各45例。对比治疗7 d后两组临床疗效及预后,分析治疗前及治疗7 d后两组神经功能[中国卒中量表(CSS)评分、神经功能(NIHSS)评分],根据不同预后将患者分为预后良好组和预后不良组,采用单/多因素Logisitic回归分析急性脑梗死预后的影响因素。结果:(1)将两组的临床疗效纳入研究并实施组间差异性比较,结果显示,高剂量组总有效率高于低剂量组(P0.05);治疗7 d后,高剂量组采用CSS评分、NIHSS评分高于低剂量组(P<0.05)。(3)将两组的预后采用m RS评分评估纳入研究并实施组间差异性比较,结果显示,高剂量组预后良好2.22%(1/45)高于低剂量组15.56%(7/45)(P<0.05)。(4)预后良好组患者年龄、治疗前CSS评分及治疗前NIHSS评分与预后不良组存在差异(P<0.05)。(5)以急性脑梗死预后为因变量,以单因素中对比有差异的指标为自变量,经多因素Logisitic回归分析急性脑梗死预后的影响因素为治疗前CSS评分及治疗前NIHSS评分。结论:高剂量阿加曲班联合丁苯酞能够有效治疗急性脑梗死患者,而急性脑梗死预后的影响因素为治疗前CSS评分及治疗前NIHSS评分。

关键词：高剂量阿加曲班低剂量阿加曲班丁苯酞急性脑梗死