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Journal of Iron and Steel Research International 2024年第3期31卷 767-777页

作者： Hong-bin Dai jian Miao jia-xin Lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Effect of quenching-partitioning treatment on the microstructure, mechanical and abrasive properties of high carbon steel

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 676-687页

作者： jian-ping Lai jia-xin Yu Jiong Wang Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education Mianyang 621010China School of Manufacturing Science and Engineering Southwest University of Science and TechnologyMianyang 621010China Central Sichuan Oil-Gas District Petro-China Southwest Oil and Gas Field CompanySuining 629000China

The present work employed the X-ray diffraction, scanning electron microscopy, electron backscattered diffraction, and electron probe microanalysis techniques to identify the microstructural evolution and mechanical and abrasive behavior of high carbon steel during quenching-partitioning treatment with an aim to enhance the toughness and wear resistance of high carbon *** showed that, with the increase in partitioning temperature from 250 to 400℃, the amount of retained austenite(RA) decreased resulting from the carbide precipitation effect after longer partitioning ***, the stability of RA generally increased because of the enhanced degree of carbon enrichment in *** the factors affecting the toughness of high carbon steel, the stability of RA associated with size, carbon content, and morphology plays a significant role in determining the toughness of high carbon *** analysis of the wear resistance of samples with different mechanical properties shows that hardness is the primary factor affecting the wear resistance of high carbon steel, and the toughness is the secondary one.

关键词： high carbon steel quenching and partitioning microstructural evolution retained austenite

Effect of mechanical threshing on damage and vigor of maize seed threshed at different moisture contents

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Journal of Integrative Agriculture 2019年第7期18卷 1571-1578页

作者： GU Ri-liang HUANG Ran jia guang-yao YUAN Zhi-peng REN Li-sha LI Li WANG jian-hua Seed Science and Technology Research Center College of Agronomy and BiotechnologyChina Agricultural University/Beijing Key Laboratory of Crop Genetics and Breeding/Beijing Innovation Research Center on the Whole Process of Crop SeedsMinistry of Agriculture

Mechanical threshing used when preparing maize seeds for planting subjects seed to damage and reduces seed *** purpose of this study was to assess the effect of mechanical threshing on the quality of maize seed threshed at different moisture contents(MCs).Seeds of dent maize JK968 and flint maize DD2 were threshed at 12,15,18,21,and 24% *** damage degree was determined by iodine staining,and seed vigor was assessed by standard germination(SG),cold test germination(CTG),accelerated aging germination(AAG),seedling emergence rate,and seedling root and shoot *** results showed that the damage percentage increased,and the seed vigor parameters decreased with increasing seed MC during threshing in both *** obtaining high seed quality,indicated by at least 90,85,and 80% of SG,AAG,and CTG,respectively,JK 968 and DD2 should be threshed at MC lower than 15 and 18%,***,the damage mainly occurred in the apical part of seeds,irrespective of the threshing MC in both *** the embryo was damaged,seedling emergence rates were significantly reduced with great influence on shoot *** to the endosperm resulted in little effect on seedling *** maize DD2 was more tolerant to mechanical threshing than dent maize *** results provided technical reference for the production and processing of high vigor maize seeds.

关键词： dent maize flint maize germination threshing vigor

Effective Identification and Annotation of Fungal Genomes

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Journal of Computer Science & Technology 2021年第2期36卷 248-260页

作者： jian Liu jia-Liang Sun Yong-Zhuang Liu College of Computer Science Nankai UniversityTianjin 300350China School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China

In the past few decades,the dangers of mycosis have caused widespread *** the development of the sequencing technology,the effective analysis of fungal sequencing data has become a *** the gradual increase of fungal sequencing data,there is now a lack of sufficient approaches for the identification and functional annotation of fungal chromosomal *** overcome this challenge,this paper firstly deals with the approaches of the identification and annotation of fungal genomes based on short and long reads sequenced by using multiple platforms such as Illumina and *** this paper develops an automated bioinformatics pipeline called PFGI for the identification and annotation *** experimental evaluation on a real-world dataset ENA(European Nucleotide Archive)shows that PFGI provides a user-friendly way to perform fungal identification and annotation based on the sequencing data analysis,and could provide accurate analyzing results,accurate to the species level(97%sequence identity).

关键词： fungal genome fungal identification bioinformatics pipeline

Electroacupuncture treatment improves motor function and neurological outcomes after cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2022年第7期17卷 1545-1555页

作者： Si-Si Li Xu-Yun Hua Mou-Xiong Zheng jia-jia Wu Zhen-Zhen Ma Xiang-Xin Xing Jie Ma Chun-Lei Shan jian-guang Xu School of Rehabilitation Science Shanghai University of Traditional Chinese MedicineShanghaiChina Department of Traumatology and Orthopedics Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Center of Rehabilitation Medicine Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina

Electroacupuncture(EA)has been widely used for functional restoration after ***,its role in post-stroke rehabilitation and the associated regulatory mechanisms remain poorly *** this study,we applied EA to the Zusanli(ST36)and Quchi(LI11)acupoints in rats with middle cerebral artery occlusion and *** found that EA effectively increased the expression of brain-derived neurotrophic factor and its receptor tyrosine kinase B,synapsin-1,postsynaptic dense protein 95,and microtubule-associated protein 2 in the ischemic penumbra of rats with middle cerebral artery occlusion and ***,EA greatly reduced the expression of myelin-related inhibitors Nogo-A and NgR in the ischemic *** kinase B inhibitor ANA-12 weakened the therapeutic effects of *** findings suggest that EA can improve neurological function after middle cerebral artery occlusion and reperfusion,possibly through regulating the activity of the brain-derived neurotrophic factor/tyrosine kinase B signal *** procedures and experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine,China(approval ***200110002)on January 10,2020.

关键词： brain-derived neurotrophic factor dendritic electroacupuncture ischemia/reperfusion motor function neurite outgrowth inhibitor-A neurological outcomes Nogo receptor synapse tyrosine kinase B

Two New Sesquiterpenes from Ligularia Duciformis

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Chemical Research in Chinese Universities 1999年第1期15卷 72-74页

作者： GAO Kun jia Zhong-jian Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

ＡｐｒｅｖｉｏｕｓｐｈｙｔｏｃｈｅｍｉｃａｌｓｔｕｄｙｏｆＬｉｇｕｌａｒｉａｄｕｃｉｆｏｒｍｉｓｄｅａｌｔｗｉｔｈｔｈｅｉｓｏｌａｔｉｏｎｏｆｃｏｎｉｆｅｒｙｌａｌｃｏｈｏｌｄｅｒｉｖａｔｉｖｅｓ［１，２］．Ｉｎｏｒ... 详细信息

ＡｐｒｅｖｉｏｕｓｐｈｙｔｏｃｈｅｍｉｃａｌｓｔｕｄｙｏｆＬｉｇｕｌａｒｉａｄｕｃｉｆｏｒｍｉｓｄｅａｌｔｗｉｔｈｔｈｅｉｓｏｌａｔｉｏｎｏｆｃｏｎｉｆｅｒｙｌａｌｃｏｈｏｌｄｅｒｉｖａｔｉｖｅｓ［１，２］．Ｉｎｏｒｄｅｒｔｏｆｉｎｄｓｅｓｑｕｉｔｅ...

关键词： Ligularia duciformis Roots Sesquiterpenes Liguducin A Liguducin B 2D NMR

Effect of stabilizing treatment on microstructure and stress rupture properties of phosphorus microalloyed Inconel 706 alloy

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Journal of Iron and Steel Research International 2023年第8期30卷 1613-1621页

作者： Sha Zhang Yu-chao Wu Yu Lil Zhong-pei Dail Dan jia Yan-fei Xu guang-sheng Zeng Zhi-ming Guo jian Liul College of Mechanical&Electrical Engineering Changsha UniversityChangsha 410022HunanChina Hunan Engineering Research Center of Research and Development of Degradable Materials and Molding Technology Changsha UniversityChangsha 410022HunanChina Changsha Kaiple Technology Co. Ltd.Changsha 410114HunanChina Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina

The microstructure and stress rupture properties of Inconel 706 alloy microalloyed with phosphorus are examined under stabilizing and unstabilizing heat treatment *** was found that applying the stabilizing treatment resulted in a 98% increment in the stress rupture life and a 215% increment in the elongation tested at 650℃/690 MPa for the alloy compared to that under the unstabilizing heat treatment *** stabilizing treatment led to the precipitation of rod-shaped and needle-shaped n phases at the grain *** of γ'-γ" co-precipitates in the grain interior were noncompact form and compact form for the alloy under unstabilizing and stabilizing heat treatment conditions,*** on the microstructure characterizations,the improvement of stress rupture properties by the stabilizing treatment was attributed to the precipitation of n phases at the grain boundaries,which can hinder cracks initiation and propagation and relieve the stress concentration.

关键词： Superalloy Stabilization ηphase γ'-γ"co-precipitate Stress rupture property

Effects of SiO_(2) on the preparation and metallurgical properties of acid oxidized pellets

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 629-636页

作者： jian-guang Lu Chen-chen Lan Qing Lyu Shu-hui Zhang jian-ning Sun School of Metallurgy Northeastern UniversityShenyang 110819China College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063009China HBIS Group Hansteel Company Handan 05600China

The effects of SiO_(2) content on the preparation process and metallurgical properties of acid oxidized pellets, including compressive strength, reduction, and softening–melting behaviors, were systematically *** structures, elemental distribution, and pore size distribution were varied to analyze the mechanism of the *** results show that with an increase in SiO_(2) content from 3.51 wt%to 7.18 wt%, compressive strength decreases from 3150 N/pellet to 2100 N/pellet and reducibility decreases from 76.5% to 71.4%.The microstructure showed that pellets with high SiO_(2) content contained more magnetite in the mineralogical ***, some liquid phases appeared, which hindered the continuous crystallization of ***, the softening–melting properties of the pellets clearly deteriorated as the SiO_(2) content *** increasing SiO_(2) content, the temperature range of the softening–melting zone decreased, and the maximum differential pressure and the comprehensive permeability index increased *** acid oxidized pellets are used as the raw materials for blast furnace smelting, it should be combined with high basicity sinters to improve the softening–melting behaviors of the comprehensive charge.

关键词： acid oxidized pellets SiO_(2)content metallurgical property mineralogical structure

A Two-Soliton Solution of Cubic Schrodinger Equation

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Chinese Physics Letters 1996年第1期13卷 17-19页

作者： YAN jia-ren CHOU guang-hui WANG Xiao-gang Department of Physics Hu'nan Normal UniversityChangsha 410081

An exact two-soliton solution of cubic Schrodinger equation is derived by using the inverse scattering method,where the transmission coefficient has one pole of second order instead of two simple *** solution describes such a process that two infinitely separated solitons approach and then pass through each other and keep straight on infinitely.

关键词： infinitely straight soliton

PATIENT-SPECIFIC BLOOD DYNAMIC SIMULATIONS IN ASSESSING ENDOVASCULAR OCCLUSION OF INTRACRANIAL ANEURYSMS

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Journal of Hydrodynamics 2009年第2期21卷 271-276页

作者： CHEN jia-liang WANG Sheng-zhang DING guang-hong YANG Xin-jian LI Hai-yun Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China Beijing Institute of Neurosurgery Beijing 100050 China Department of Biomedical Engineering Capital Medical University Beijing 100050 China

According to recent studies, there are various potential predictors for surgical outcome for cerebral aneurysms. An accurate surgical outcome assessment would help make better-informed decisions and avoid the risk of rebleeding. It is well known that hemodynamic factors play an important role in the pathogenesis and treatment of intracranial aneurysms. In this article, a computational fluid dynamic analysis is applied to one patient-specific model of the cerebral aneurysm located at the tip of basilar artery, by which the differences of hemodynamic parameters before and after endovascular treatment may be evaluated. Based on the model, we show that the flow behavior near the neck of the aneurysm sees great differences after endovascular treatment as compared with that before treatment, which also affects the wall shear stress and the displacement distribution. In addition, our whole simulation process is based on a series of CFD commercial software packages, which are easily available for doctors to implement such a method in their daily practice. These results would be used to assess the outcome of endovascular treatment for the aneurysm occlusion.

关键词： hemodynamics numerical simulation intracranial aneurysm