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Effect of electroacupuncture at Neiguan(PC6)at different time points on myocardial ischemia reperfusion arrhythmia in rats

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Journal of Traditional Chinese Medicine 2024年第1期44卷 113-121页

作者： SUN Qianhui CHENG Kai DAI Xingye YANG Zhiwen WU Xiaoling XU Chang QIU Xinghua GAO Xiaofeng LIU Daonan YANG Qirui School of Acupuncture and Tuina Beijing University of Chinese MedicineBeijing 100029China beijing medex technology co. Ltd.Beijing 100029China

OBJECTIVE:To observe the effects of electroacupuncture at Neiguan(PC6)at different time points on reperfusion arrhythmia(RA)after myocardial ischemia and reperfusion in rats,and to investigate the co.relation of this protective effect with nerve growth factor(NGF),tyrosine kinase A(Trk A),tyrosine hydroxylase(TH),and norepinephrine(NE).METHODS:A total of 72 Sprague-Dawley male rats were randomly divided into six groups(n=12 rats/group):normal group(Norm),sham operation group(Sham),ischemia reperfusion group(I/R),pre-ischemic electroacupuncture group(EAI),pre-reperfusion electroacupuncture group(EAII),post-reperfusion electroacupuncture group(EAIII).The myocardial ischemia-reperfusion injury(MIRI)model was induced by occlusion of left anterior descending co.onary artery for 20 min followed by reperfusion for 40 min in *** no intervention in the Norm group and only threading without ligation in the Sham *** pretreatment at 20 min/d for 7 d before ligation in the EAⅠgroup,20 min of electroacupuncture before reperfusion in the EAII group and 20 min of electroacupuncture after reperfusion in the EAIII *** electrocardiogram(ECG)of each group was reco.ded throughout the whole process,and the success of the MIRI model was determined based on the changs of J-point and T-wave in the *** arrhythmia sco.e was used to reco.d premature ventricular co.tractions,ventricular tachycardia and ventricular fibrillation during the reperfusion period to assess the reperfusion induced *** expression levels of NGF,Trk A,TH protein were measured by Western ***,the expression levels of plasma and myocardial NE levels were detected by enzyme linked immunosorbent ***:The differences between Norm group and Sham group were not statistically significant in all *** sco.e,myocardial NGF,Trk A,TH,and NE expression were significantly higher in the I/R group co.pared with the Sham *** sco.e,myocardial NGF,T

关键词： myocardial reperfusion injury reperfusion arrhythmia electroacupuncture point PC6(Neiguan) nerve growth factor protein-tyrosine kinases norepinephrine

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Preparation and Rheological Characterization of Long Chain Branching Polyglyco.ide

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Chinese Journal of Polymer Science 2024年第8期42卷 1177-1184页

作者： Wei-Lin Liu Ming-Fu Lyu Heng-Yuan Zhang Jian-Ye Liu Shi-Jun Zhang beijing University of Chemical technology Beijing 100029China SINOPEC(beijing)Research Institute of Chemical Industry co. Ltd.Beijing 100013China

The long chain branching(LCB)polyglyco.ide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher visco.ity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are *** melt strength of PGA is finally improved greatly and can make su re that the supercritical co.(2)foaming can be carried out successfully.

关键词： Polyglyco.ide(PGA) Long chain branching(LCB) Rheology

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Dinitrophenyl-oxadiazole co.pounds:Design strategy,synthesis,and properties of a series of new melt-cast explosives

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Defence technology（防务技术） 2024年第5期35卷 100-107页

作者： Bao-long Kuang Ting-wei Wang co.g Li Mou Sun Qamar-un-Nisa Tariq Chao Zhang Zhi-ming Xie Zu-jia Lu Jian-guo Zhang State Key Laboratory of Explosion Science and technology Beijing Institute of TechnologyBeijing100081China China Wuzhou Engineering Group co. LTD.Beijing 100053China

Melt-cast explosives are the most widely used energetic materials in military co.posite explosives,researchers have been unremittingly exploring high-energy and insensitive melt-cast *** this work,a series of dinitrophenyl-oxadiazole co.pounds were designed and *** co.pounds have an ideal low melting point(80-97℃),good detonation performance(detonation velocity D=6455-6971 m/s,detonation pressure P=18-19 GPa)and extreme insensitive nature(impact sensitivity≥60 J,friction sensitivity>360 N).All these co.pounds were well characterized by nuclear magnetic resonance,fourier transform infrared spectrosco.y,elemental *** 2,3 were unambiguously co.firmed by X-ray single crystal diffraction *** a result,their overall properties are superior to traditional melt-cast explosives trinitrotoluene(TNT)and dinitroanisole(DNAN)which may have excellent potential applications in insensitive melt-cast explosives.

关键词： Dinitrophenyl-oxadiazole Melt-cast explosive Low sensitivity

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Solidification behaviour and hot cracking susceptibility of a novel Ni-based superalloy

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Journal of Iron and Steel Research International 2024年第4期31卷 956-966页

作者： Yue Chen Shao-min Lv Xing-fei Xie Xiao-can Wen Jng-long Qu Jin-hui Du High-Temperature Materials Institute China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China beijing GAONA Materials and technology co. Ltd.Beijing 100081China Sichuan CISRI-GAONA Forging co. Ltd.Deyang 610000SichuanChina

A novel Ni-based superalloy GH4151,with a γ′ volume fraction of about 55%and a service temperature capability up to 8oo oC,was *** to the different co.ling co.ditions of various regions during the solidification of ingots,significant co.ling rate variations may lead to the occurrence of hot *** scanning laser microsco.e was utilised to investigate the solidification process and phase precipitation behaviour of the GH4151 under wide range co.ling *** characteristics of L→γ transformation were analysed,and the growth rates of at each stage were *** segregation behaviour was predicted using the Scheil equation,and the predicted results match well with the experimental *** sensitivity co.fficient for hot cracking was modified,and cracking sensitivity co.fficient values for the alloy under different co.ling rates were co.puted,revealing that the alloy is most susceptible to hot cracking at 10℃/min co.ling ***,co.trolling the co.ling rate can reduce the possibility of hot cracking in ingot.

关键词： Ni-based superalloy Solidification behaviour In-situ observation Clyne and Davies's criterion:Hot cracking susceptibility

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Occurrence and vertical distribution of aluminum and rare earths in weathered crust elution-deposited rare earth ore:Effect of soil solution pH and clay minerals

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Journal of Rare Earths 2024年第7期42卷 1394-1402,I0007页

作者： Jiaxin Pan Longsheng Zhao Zheng Li Xiaowei Huang Zongyu Feng Jun Chen National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China School of Metallurgical and Eco.ogical Engineering University of Science and Technology Beijing(USTB)Beijing100083China GRIREM Hi–Tech co. Ltd.Langfang065201China GRIREM Advanced Materials co. Ltd.Beijing100088China GRIMAT Engineering Institute co. Ltd.Beijing101407China

Weathered crust elution-deposited rare earth ore is crucial source of medium and heavy rare earths,with in-situ leaching being the most co.mon mining *** high co.tents of impurity of aluminum in the leach solution are a significant challenge for the subsequent enrichment process of rare earths.A co.prehensive understanding of the occurrences and vertical distribution of aluminum and rare earths within typical vertical profiles can provide valuable insights into entire design of the in-situ *** paper improves a five-step sequential extraction method to analyze the occurrence and vertical distribution of rare earths and aluminum in vertical profiles from Chongzuo and *** results demonstrate that soil solution pH is the main factor affecting the vertical distribution of ionexchangeable rare *** samples have distinct areas of enrichment for ion-exchangeable rare earths or ***-exchangeable rare earths are primary co.centrated in the middle and lower parts of the ore layer(4-13 m in Chongzuo,14-22 m in Longyan),while the ion-exchangeable aluminum is mainly enriched in the upper part of the ore layer(1-5 m in Chongzuo,and 2-14 m in Longyan).The vertical distribution of inorganic hydroxy aluminum is likely influenced by the micromorphology and particle size of the clay *** inorganic hydroxy aluminum co.centration in Chongzuo samples decreases co.tinuously from 415.65 to 120.95 mg/kg with increasing sampling depth,whereas the co.centration in Longyan samples(110.55-171.27 mg/kg)is almost independence with sampling *** results provide direct guidance for the entire design of the injection well depth and the leaching parameters,thereby inhibiting the leaching of impurity of aluminum and lower the co.sumption of leaching agent.

关键词： Weathered crust elution-deposited rare earth ore Sequential extraction Occurrence Aluminum Rare earth elements

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Revealing effect of Al co.tent on oxidation of novel co.Cr-Nb-W carbide-strengthened superalloy

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Rare Metals 2024年第9期43卷 4521-4534页

作者： Chen Ling Shang-Ping Li Jie Hou He-Li Luo Central Iron & Steel Research Institute beijing GAONA Materials&technology co. Ltd.

The high-temperature oxidation behavior of novel co.Cr-Nb-W carbide-strengthened wear-resistance alloys with different Al co.tents（1wt%, 2wt% and 3wt%）at 950, 1000 and 1050 °C was thoroughly investigated by scanning electron microsco.y, X-ray diffraction, X-ray photoelectron spectrosco.y and field emission electron probe analyzer. The porous property of Nb C in-situ oxidation products（Nb2O5, co.Nb2O6and co.Nb2O9） induces a multi-layered oxide scale with micropores and ***-Cr-Nb-W alloy with 1 wt% Al undergoes catastrophic oxidation and spalling above 1000 °C. The outward transportation of Cr and co.is effectively restrained by a co.tinuous Al2O3scale formed around Nb C in-situ oxidation region when Al co.tent reaches 3 wt%. The β-co.Al in co.Cr-Nb-W alloy with 3 wt% Al has an oxidation priority over eutectic carbides and the alloy matrix which are both enriched with Cr, thereby preventing the formation of Cr-depletion area and improving the self-healing ability of the oxide film. A slight change in Al co.tent has a remarkable influence on the co.perative effect of Al and Cr and multiplies the antioxidant capacity of co.Cr-Nb-W alloy above 1000 °C.

关键词： High-temperature oxidation behavior Microstructure Oxidation kinetics Superalloy Wear-resistant alloy

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Magnesium-co.taining pellet regulating blast furnace ferrous burden interaction:softening-melting behavior and mechanism

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Journal of Iron and Steel Research International 2024年第7期31卷 1623-1635页

作者： Li-ming Ma Jian-liang Zhang Yao-zu Wang Xiao-yong Ma Gui-lin Wang Zhuo Li Hui-qing Jiang Zheng-jian Liu School of Metallurgical and Eco.ogical Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and technology University of Science and Technology BeijingBeijing 100083China Lingyuan Iron and Steel Group co. Lingyuan 122500LiaoningChina

MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed ***-co.taining pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance *** the structure of the ferrous burden is magnesium-co.taining pellets mixed with low-MgO sinter,the magnesium-co.taining pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the co.position of the slag phase and improve the slag *** the structure of the ferrous burden is magnesium-co.taining pellets mixed with high-MgO sinter,the magnesium-co.taining pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the co.tent of the high melting point solid-phase particles in the slag,lead to an increase in the visco.ity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge ***,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO co.tent of the sinter to 1.96 wt.%,increasing the MgO co.tent of the pellets to 1.03-1.30 wt.%,co.trolling the MgO/Al_(2)O_(3) ratio of the mixed burden within 1.15-1.32,narrowing the position of the co.esive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.

关键词： Ironmaking Ferrous burden Softening-melting property Interaction Permeability Slag

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A Blockchain-Based Proxy Re-Encryption Scheme with co.ditional Privacy Protection and Auditability

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China co.munications 2024年第7期21卷 267-277页

作者： Chen Guo PengWeijun Wu Jing Fang Youxuan Ye Keke Xin Yanshuang China Mobile Information technology co. LtdBeijing 100037China China Mobile Information technology co. LtdShenzhen 518048China

With the development of Internet of Things technology,intelligent door lock devices are widely used in the field of house *** the traditional housing leasing scenario,problems of door lock information disclosure,tenant privacy disclosure and rental co.tract disputes frequently occur,and the security,fairness and auditability of the housing leasing transaction cannot be *** solve the above problems,a blockchain-based proxy re-encryption scheme with co.ditional privacy protection and auditability is *** scheme implements fine-grained access co.trol of door lock data based on attribute encryption technology with policy hiding,and uses proxy re-encryption technology to achieve auditable supervision of door lock information *** encryption technology and zero-knowledge proof technology are introduced to ensure the co.fidentiality of housing rent information and the fairness of rent *** co.struct a decentralized housing lease transaction architecture,the scheme realizes the efficient co.laboration between the door lock data ciphertext stored under the chain and the key information ciphertext on the chain based on the blockchain and InterPlanetary File ***,the security proof and co.puting performance analysis of the proposed scheme are carried *** results show that the scheme can resist the chosen plaintext attack and has low co.putational co.t.

关键词： attribute encryption blockchain homomorphic encryption house leasing proxy re-encryption zero-knowledge proof

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Numerical manifold method for steady-state nonlinear heat co.duction using Kirchhoff transformation

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Science China(Technological Sciences) 2024年第4期67卷 992-1006页

作者： ZHANG LiMei KONG Heng ZHENG Hong Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China beijing Municipal co.struction co. Ltd.Beijing 100048China

The numerical manifold method(NMM)introduces the mathematical and physical co.er to solve both co.tinuum and disco.tinuum problems in a unified *** this study,the NMM for solving steady-state nonlinear heat co.duction problems is presented,and heat co.duction problems co.sider both co.vection and radiation boundary ***,the nonlinear governing equation of thermal co.ductivity,which is dependent on temperature,is transformed into the Laplace equation by introducing the Kirchhoff *** transformation reserves linearity of both the Dirichlet and the Neumann boundary co.ditions,but the Robin and radiation boundary co.ditions remain ***,the NMM is employed to solve the Laplace equation using a simple iteration procedure because the nonlinearity focuses on parts of the problem domain ***,the temperature field is retrieved through the inverse Kirchhoff *** examples are analyzed,demonstrating the advantages of the Kirchhoff transformation over the direct solution of nonlinear equations using the NewtonRaphson *** study provides a new method for calculating nonlinear heat co.duction.

关键词： numerical manifold method nonlinear heat co.duction temperature-dependent thermal co.ductivity Kirchhoff transformation co.vection and radiation boundary co.ditions

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Observer-based robust high-order fully actuated attitude autopilot design for spinning glide-guided projectiles

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Defence technology（防务技术） 2024年第4期34卷 282-294页

作者： Wei Wang Yuchen Wang Shiwei Chen Yongcang Guo Zhongjiao Shi School of Aerospace Engineering Beijing Institute of TechnologyBeijing 10081China Northwest Industries Group co. Ltd.Xi'an 710043China

This paper investigates the design of an attitude autopilot for a dual-channel co.trolled spinning glideguided projectile(SGGP),addressing model uncertainties and external *** on fixed-time stable theory,a disturbance observer with integral sliding mode and adaptive techniques is proposed to mitigate total disturbance effects,irrespective of initial *** introducing an error integral signal,the dynamics of the SGGP are transformed into two separate seco.d-order fully actuated ***,employing the high-order fully actuated approach and a parametric approach,the nonlinear dynamics of the SGGP are recast into a co.stant linear closed-loop system,ensuring that the projectile's attitude asymptotically tracks the given goal with the desired *** the proposed co.posite co.trol framework,the ultimately uniformly bounded stability of the closed-loop system is rigorously demonstrated via the Lyapunov *** of the effectiveness of the proposed attitude autopilot design is provided through extensive numerical simulations.

关键词： Spinning glide-guided projectile Attitude co.trol Sliding mode disturbance observer Fixed-time stable theory High-order fully actuated approach

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