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Development of Ti-Al-Ta-Nb-(Re)near-αhigh temperature titanium alloy:Microstructure,thermal stability and mechanical properties

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Journal of Materials Science & Technology 2022年第14期109卷 1-11页

作者： Juan Li Yaqun xu Wenlong xiao Chaoli Ma xu huang Key Laboratory of Aerospace Advanced Materials and Performance of Ministry of Education School of Materials Science and EngineeringBeihang UniversityBeijing 100191China AECC Beijing Institute Of Aeronautical Materials Beijing 100095China

Mechanical properties and microstructural stability under the service temperature are important to the high temperature titanium alloy.In order to evaluate the potential in increase the service temperature of Ti alloy,two near-αTi alloys with high content of Al asα-stabilizer and Ta,Nb and/or Re asβ-stabilizers were designed and prepared by ingot metallurgy and thermomechanical processing,and the microstructure and mechanical properties before and after thermal exposure at 650℃ for 100 h were characterized.The results indicated that due to the weakβ-stabilizing ability of Ta and Nb elements,only a small amount ofβphase was formed in Ti-10Al-4Ta-2Nb alloy.With a trace Re addition,theβphase was obviously increased in Ti-10Al-4Ta-2Nb-0.25Re,indicating that the Re was a strongβ-stabilizer.Under the same thermomechanical conditions,the Re addition decreased the volume fraction of primaryα(α_(p))phase and refined the secondaryα(α_(s))phase evidently.The primaryαphase presented an obvious core-shell structure in the Ti-10Al-4Ta-2Nb alloy,with higher Al concentration in the shell.While the core-shell structure was not obvious in the Re-containing alloy due to the Re decreases the diffusion of Al,Ta and Nb elements.A large number of orderedα_(2)precipitates can be observed in theα_(p)andα_(s) phases of two alloys.Theα_(2)precipitates continuously grew up during thermal exposure,however,their growth rate in theα_(s)phase of Re-containing alloy were lower than that of Ti-10Al-4Ta-2Nb alloy.Although plenty of orderedα_(2)precipitates formed in the Ti-10Al-4Ta-2Nb alloy,the alloy had a certain plasticity at room temperature.The trace Re addition evidently increased the tensile strength but caused the decrease of the plasticity.After thermal exposure,the strength was further increased,while the plasticity was decreased for both of alloys.

关键词： Titanium alloy High temperature Microstructure Mechanical properties α_(2)precipitates Thermal exposure

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Geochronology,Petrogenesis and Tectonic Setting of the Late Jurassic I-type Granites in the North Qinling Orogenic Belt,Central China

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Acta Geologica Sinica(English Edition) 2023年第4期97卷 1132-1149页

作者： huang Yanna LI Dunpeng xiao Aifang xu Songming College of Zijin Geology and Mining Fuzhou UniversityFuzhou 350108China

The North Qinling Orogenic Belt(NQOB)is a composite orogenic belt in central China.It started evolving during the Meso-Neoproterozoic period and underwent multiple stages of plate subduction and collision before entering intra-continental orogeny in the Late Triassic.The Meso-Cenozoic intra-continental orogeny and tectonic evolution had different responses in various terranes of the belt,with the tectonic evolution of the middle part of the belt being particularly controversial.The granites distributed in the Dayu and Kuyu areas in the middle part of the NQOB can provide an important window for revealing the geodynamic mechanisms of the NQOB.The main lithology of Dayu and Kuyu granites is biotite monzogranite,and the zircon U-Pb dating yielded intrusive ages of 151.3±3.4 Ma and 147.7±1.5 Ma,respectively.The dates suggest that the biotite monzogranite were formed at the end of the Late Jurassic.The whole-rock geochemistry analysis shows that the granites in the study areas are characterized by slightly high SiO_(2)(64.50-68.88 wt%)and high Al_(2)O_(3)(15.12-16.24 wt%)and Na_(2)O(3.55-3.80 wt%)contents.They are also enriched in light rare earth elements,large ion lithophile elements(e.g.,Ba,K,La,Pb and Sr),and depleted in high field strength elements(HFSEs)(e.g.,Ta,Nb,P and Ti).Additionally,the granites have weakly negative-slightly positive Eu anomalies(δEu=0.91-1.19).Zircon Lu-Hf isotopic analysis showedε_(Hf)(t)=-6.1--3.8,and the two-stage model age is T_(2DM(crust))=1.5-1.6 Ga.The granites in the study areas are analyzed as weak peraluminous high-K calc-alkaline I-type granites.They formed by partial melting of the thickened ancient lower crust,accompanied by the addition of minor mantle-derived materials.During magma ascent,they experienced fractional crystallization,with residual garnet and amphibole for a certain proportion in the magma source region.Comprehensive the geotectonic data suggest that the end of the Late Jurassic granite magmatism in the Dayu and Kuyu areas represents a compression-extension tra

关键词： partial melting tectonic transition I-type granite Late Jurassic North Qinling Orogenic Belt

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Leap trajectory tracking control based on sliding mode theory for hypersonic gliding vehicle

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第3期23卷 188-207页

作者： Kai AN Zhen-yun GUO Wei huang xiao-ping xu Science and Technology on Scramjet Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China Beijing Interdisciplinary Center National University of Defense TechnologyBeijing 100101China

The aim of this study was to develop robust tracking control schemes for the 3D leap trajectory of hypersonic gliding vehicles using sliding mode theory. A predictor-corrector guidance method was applied to the generation of the reference trajectory, and drag acceleration was selected as the profile of reference tracking. A combined super-twisting sliding mode controller(CST-SMC) is proposed to decrease the tracking error and guarantee the tracking performance in the presence of system nonlinearities compared to three other common controllers: the linear sliding mode controller(L-SMC), global fast terminal sliding mode controller(GFT-SMC), and super-twisting sliding mode controller(ST-SMC). By using the developed controller, the system state of a second-order drag acceleration tracking error system can approach the global fast terminal sliding manifold in finite time. By using the Lyapunov approach, sufficient conditions are deduced to ensure that the tracking performance is obtained for a closed-loop system. Furthermore, we show that the controller is robust to initial uncertain parameters and other perturbations, as validated by simulation results with appropriate gains.

关键词： Predictor-corrector guidance Drag tracking Sliding mode control(SMC) Super twisting control

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c-MYC-mediated TRIB3/P62^(+) aggresomes accumulation triggers paraptosis upon the combination of everolimus and ginsenoside Rh2

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Acta Pharmaceutica Sinica B 2022年第3期12卷 1240-1253页

作者： Min-Xia Su Yu-Lian xu xiao-Ming Jiang Mu-Yang huang Le-Le Zhang Luo-Wei Yuan Xiao-Huang Xu Qi Zhu Jian-Li Gao Jia-Hong Lu Xiuping Chen Ming-Qing huang Yitao Wang Jin-Jian Lu State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao 999078China School of Pharmaceutical Sciences Zhejiang Chinese Medical UniversityHangzhou 310000China College of Pharmacy Fujian University of Traditional Chinese MedicineFuzhou 350000China Mo E Frontiers Science Center for Precision Oncology University of MacaoMacao 999078China

The mammalian target of rapamycin(m TOR) pathway is abnormally activated in lung cancer.However, the anti-lung cancer effect of m TOR inhibitors as monotherapy is modest. Here, we identified that ginsenoside Rh2, an active component of Panax ginseng C. A. Mey., enhanced the anti-cancer effect of the m TOR inhibitor everolimus both in vitro and in vivo. Moreover, ginsenoside Rh2 alleviated the hepatic fat accumulation caused by everolimus in xenograft nude mice models. The combination of everolimus and ginsenoside Rh2(labeled Eve-Rh2) induced caspase-independent cell death and cytoplasmic vacuolation in lung cancer cells, indicating that Eve-Rh2 prevented tumor progression by triggering paraptosis. EveRh2 up-regulated the expression of c-MYC in cancer cells as well as tumor tissues. The increased cMYC mediated the accumulation of tribbles homolog 3(TRIB3)/P62+ aggresomes and consequently triggered paraptosis, bypassing the classical c-MYC/MAX pathway. Our study offers a potential effective and safe strategy for the treatment of lung cancer. Moreover, we have identified a new mechanism of TRIB3/P62+ aggresomes-triggered paraptosis and revealed a unique function of c-MYC.

关键词： Everolimus Ginsenoside Rh2 Paraptosis Aggresomes P62 TRIB3 c-MYC Lung cancer

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Wide Pulse Width Electroacupuncture Ameliorates Denervation-Induced Skeletal Muscle Atrophy in Rats via IGF-1/PI3K/Akt Pathway

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Chinese Journal of Integrative Medicine 2021年第6期27卷 446-454页

作者： huang xiao-qing xu Jin-sen YE xiao-ran CHEN xuan Key Laboratory of Acupuncture Instrument Fujian Academy of Chinese Medical SciencesFuzhou(350003)China Fujian Key Laboratory of Propagated Sensation along Meridian Institute of Meridians and Collaterals MedicineFujian Academy of Chinese Medical SciencesFuzhou(350003)China

Objective:To evaluate the effect of the pulse width of electroacupuncture(EA)in the treatment of denervation-induced skeletal muscle atrophy in rats and examine the role of insulin-like growth factor 1(IGF-1)/phosphatidylinositol 3-kinase(PI3 K)/Akt signaling pathway during EA.Methods:Sciatic nerve functional index(SFI),muscle wet weight and the cross-sectional area(CSA)of the gastrocnemius muscle were analyzed after treatment in model rats with EA of various pulse widths(0.5,50,100 and 200 ms).The apoptosis index(AI)and paired box(PAX)3 and PAX7 protein expression were also determined.Further,the mRNA and protein expressions of components of IGF-1/PI3 K/Akt pathway and their downstream targets were determined,along with the inhibiting effect of the pathway with a PI3-specific inhibitor.Results:EA with a pulse width of 200 ms was found to have the best effect with regard to increasing SFI,CSA and muscle weight,decreasing AI,and increasing the expression of PAX3 and PAX7.The IGF-1/PI3 K/Akt pathway was found to be activated by denervation,although the downstream forkhead box O(FoxO)pathway was not suppressed by its activation.The PI3 K/Akt pathway and its downstream molecule mammalian target of rapamycin(mTOR)were up-regulated further by EA to promote muscle protein synthesis.Meanwhile,the expressions of downstream FoxO and F-box protein 32(ATROGIN-1)were down-regulated to reduce protein degradation.Conclusions:EA with 200-ms pulse width was found to have a more significant effect than 0.5-ms EA.The positive effects of EA disappeared after inhibition of the PI3 K/Akt pathway.

关键词： denervation muscle atrophy electroacupuncture pulse width IGF-1/PI3K/Akt pathway

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Regulation of Axon Initial Segment Diameter by COUP-TFI Fine-tunes Action Potential Generation

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Neuroscience Bulletin 2022年第5期38卷 505-518页

作者： xuanyuan Wu Haixiang Li Jiechang huang Mengqi xu Cheng xiao Shuijin He School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China Institute of Neuroscience Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China University of Chinese Academy of Sciences Beijing 100049China School of Anesthesiology Xuzhou Medical UniversityXuzhou 221004China

The axon initial segment(AIS)is a specialized structure that controls neuronal excitability via action potential(AP)generation.Currently,AIS plasticity with regard to changes in length and location in response to neural activity has been extensively investigated,but how AIS diameter is regulated remains elusive.Here we report that COUP-TFI(chicken ovalbumin upstream promotor-transcription factor 1)is an essential regulator of AIS diameter in both developing and adult mouse neocortex.Either embryonic or adult ablation of COUP-TFI results in reduced AIS diameter and impaired AP generation.Although COUP-TFI ablations in sparse single neurons and in populations of neurons have similar impacts on AIS diameter and AP generation,they strengthen and weaken,respectively,the receiving spontaneous network in mutant neurons.In contrast,overexpression of COUP-TFI in sparse single neurons increases the AIS diameter and facilitates AP generation,but decreases the receiving spontaneous network.Our findings demonstrate that COUP-TFI is indispensable for both the expansion and maintenance of AIS diameter and that AIS diameter fine-tunes action potential generation and synaptic inputs in mammalian cortical neurons.

关键词： COUP-TFI Axon initial segment Action potential Diameter

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Secure transmission for heterogeneous cellular network with limited feedback

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Science China(Information Sciences) 2020年第12期63卷 53-66页

作者： Wenyu JIANG Kaizhi huang Shuaifang xiao xiaoming xu PLA Strategic Support Force Information Engineering University

We study physical layer secure transmission with limited feedback in heterogeneous cellular networks. A transmission protocol is designed to obtain more secure and accurate channel state information(CSI) for enhancing the secrecy performance. Under the proposed protocol, we derive expressions of coverage probability and secrecy outage probability to analyze the security performance with different system parameters such as feedback CSI length and number of antennas. Furthermore, an iteration algorithm is proposed to balance the tradeoff between the feedback and transmission time, and maximize the average secrecy throughput under coverage and secrecy outage constrains. Numeric results demonstrate the optimal feedback overhead and the maximum average secrecy throughput are influenced by the number of antennas.

关键词： physical layer security heterogeneous cellular networks limited feedback secure transmission average secrecy throughput

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Effect of Acupuncture on Endometrial Blood Flow in Women Undergoing in vitro Fertilization Embryo Transfer: A Single Blind, Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2024年第1期30卷 10-17页

作者： DONG Hao-xu Wu xiao ZHOU Qin huang Dong-mei ZHANG Ming-min huang Guang-ying YANG Wei Department of Integrated Traditional Chinese and Western Medicine Tongji HospitalHuazhong University of Science and TechnologyWuhan(430030)China Department of Obstetrics and Gynecoiogy Tongji HospitalHuazhong University of Science and TechnologyWuhan(430030)China Institute of Integrated Traditional Chinese and Western Medicine Tongji HospitalHuazhong University of Science and TechnologyWuhan(430030)China Department of Reproductive Medicine Tongji HospitalHuazhong University of Science and TechnologyWuhan(430030)China

Objective: To evaluate the effect of manual acupuncture on endometrial blood flow parameters by three-dimensional(3D) power Doppler ultrasound in women undergoing in vitro fertilization embryo transfer(IVF-ET). Methods: Seventy patients undergoing IVF-ET were equally randomized into traditional or sham acupuncture treatment group for totally 4 days(from the day of oocyte aspiration to the day of embryo transfer) of treatment by random envelope method at the Reproductive Medicine Center and Outpatient Department of Integrated Traditional Chinese and Western Medicine, Tongji Hospital, Tongji Medicine College, Huazhong University of Science and Technology from January 2013 to December 2015. Patients in the traditional acupuncture group accepted traditional acupuncture methods with manual acupuncture, and Zhongji(CV3), Qihai(CV 6), Sanyinjiao(SP6), Taichong(LR 3), Tianshu(ST 25), Guilai(ST 29) and Zusanli(ST 36) were chosen. Patients at the sham acupuncture group accepted shallow acupuncture methods at 4 non-meridian points at each shoulder and upper arm. Outcome measures included endometrial ultrasonic indices such as vascularization index(VI), flow index(FI) and vascularization flow index(VFI), endometrial thickness and volume, subendometrial VI(sVI), subendometrial FI(sFI), subendometrial VFI(sVFI), implantation rate, clinical pregnancy rate, abortion rate, live birth rate and number of live births. Results: Finally, 34 patients in the traditional acupuncture group and 35 in the sham acupuncture group completed this trial. VI, FI and VFI of the traditional acupuncture group were significantly higher than those in the sham acupuncture group(P0.05). Conclusions: Manual acupuncture performed after oocyte aspiration and before transplantation improved the endometrial blood flow parametersVI, RI and VFI in women

关键词： acupuncture endometrial blood flow endometrial receptivity in vitro fertilization randomized controlled trial

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Decoy-state method for quantum-key-distribution-based quantum private query

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Science China(Physics,Mechanics & Astronomy) 2022年第4期65卷 41-48页

作者： Bin Liu Shuang Xia Di xiao Wei huang Bingjie xu Yang Li College of Computer Science Chongqing UniversityChongqing 400044China Science and Technology on Communication Security Laboratory Institute of Southwestern CommunicationChengdu 610041China

The quantum private query(QPQ)is a quantum solution for the symmetrically private information retrieval problem.We study the security of quantum-key-distribution-based QPQ with weak coherent pulses.The result shows that multiphoton pulses have posed a serious threat to the participant’s privacy in QPQ protocols.Then we propose a decoy-state method that can help the honest participant detect the attack by exploiting multiphoton pulses and improving the key distillation process to defend against such attack.The analysis demonstrates that our decoy-state method significantly improves the security of the QPQ with weak coherent pulses,which solves a major obstacle in the practical application of the QPQ.

关键词： quantum private query symmetrically private information retrieval quantum key distribution decoy state weak coherent pulse

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Catalytic asymmetric dearomative azo-Diels–Alder reaction of 2-vinlyindoles

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Chinese Chemical Letters 2024年第4期35卷 357-362页

作者： Yu-Hang Miao Zheng-xu Zhang xu-Yi huang Yuan-Zhao Hua Shi-Kun Jia xiao xiao Min-Can Wang Li-Ping xu Guang-Jian Mei Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450052China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China Institute of Pharmaceutical Science and Technology Zhejiang University of TechnologyHangzhou 310014China

Due to the high electrophilic nature of azo-dienophiles, azo-Diels–Alder proceeds rapidly even without the need of a catalyst and is therefore regarded as the “click reaction”. This spontaneity causes strong background reaction and poses a daunting challenge to chemists for developing the catalytic asymmetric version. Reported herein is the first catalytic asymmetric dearomative azo-Diels–Alder reaction between2-vinylindoles and triazoledione. This protocol makes use of the high energy barrier of dearomatization to avert the strong background reaction of azo-Diels–Alder reaction, allowing the implementation of the projected reaction at ambient temperature. Density functional theory calculations have been performed to gain insights into the reaction mechanism and the origins of the enantioselectivity. By using this method,a variety of tetracyclic indole derivatives have been readily prepared in good to excellent yields and with excellent diastereo-and enantio–selectivities(33 examples, up to 97% yield and >99% ee, >20:1 dr).

关键词： Catalytic asymmetric dearomatization Azo-Diels–Alder reaction 2-Vinylindoles Chiral phosphoric acid Tetracyclic indole derivatives

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