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Journal of Materials Science & Technology 2023年第31期162卷 118-130页

作者： Xuewei Zhang Weijie Wu Yuan Li Jinxu Li Lijie Qiao Corrosion and Protection Center Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China

The corrosion form and mechanical properties deterioration of mooring chain steel in simulated deep-sea environments were investigated.With the increase of ocean depth,not only the pressure increases,but also the dissolved oxygen content decreases.These two factors affect corrosion evolution of mooring chain steel in simulated deep-sea environments,which was studied for the first time.Compared with uniform corrosion of mooring chain steel in shallow sea with sufficient oxygen,low dissolved oxygen leads to the corrosion dominated by pitting with pit covers.Meanwhile,hydrostatic pressure distinctly accelerates pitting initiation and propagation.The higher the hydrostatic pressure is,the more serious the pitting is.For failure mechanism of unstressed mooring chain steel serving in simulated deep-sea environments,both absorbed hydrogen and corrosion morphology can degrade the ductility of mooring chain steel,in which the leading factor depends on the service time.The severe pitting is the main factor and causes remarkable ductility loss of the steel after long-term immersion.But hydrogen plays an important role on elongation loss in early stage.

关键词： High-strength low-alloy steel Dissolved oxygen hydrostatic pressure Pitting corrosion Failure mechanism

Large enhancement of magnetocaloric effect induced by dual regulation effects of hydrostatic pressure in Mn_(0.94)Fe_(0.06)NiGe compound

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Journal of Materials Science & Technology 2022年第19期114卷 73-80页

作者： He Zhou Dekun Wang Zhe Li Junzhuang Cong Ziyuan Yu Shuo Zhao Peng Jiang Daoyong Cong Xinqi Zheng Kaiming Qiao Hu Zhang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China College of Physics and Electronic Engineering Key Laboratory for Advanced Functional and Low Dimensional Materials of Yunnan Higher Education InstituteQujing Normal UniversityQujing 655011China MultiFields Technologies(Beijing)Co.Ltd. Beijing 100190China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

MM'X(M,M'=transition metals,X=carbon or boron group elements)compounds could exhibit large magnetocaloric effect due to the magnetostructural transition,and the composition regulation has been widely studied to realize the magnetostructural transition.Moreover,the magnetostructural transition is also sensitive to the pressure.Herein,the effect of hydrostatic pressure on magnetostructural transformation and magnetocaloric effect has been investigated in Mn_(0.94)Fe_(0.06)NiGe compound.Dual regulation effect of lowering structural transition temperature and strengthening ferromagnetic(FM)state of martensite is realized by applying hydrostatic pressure,which would greatly improve the magnetocaloric effect of Mn_(0.94)Fe_(0.06)NiGe compound.Moreover,the first-principles calculations have also been performed to discuss the origin of the regulation effect under hydrostatic pressure,and it indicates that the hydrostatic pressure can stabilize the hexagonal structure and decrease the structural transition temperature.The maximum isothermal entropy change increases by 109%from 4.3 J/(kg K)under 0 GPa to 9.0 J/(kg K)under 0.402 GPa for a magnetic field change of 0-3 T.This work proves that the hydrostatic pressure is an effective method to regulate the magnetostructural transition and enhance magnetocaloric effect in MM'X compounds.

关键词： Magnetocaloric effect Magnetostructural transition hydrostatic pressure Magnetic properties

Effects of magnetic field and hydrostatic pressure on the antiferromagnetic-ferromagnetic transition and magneto-functional properties in Hf_(1-x)Ta_(x)Fe_(2)alloys

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Tungsten 2023年第4期5卷 503-511页

作者： Feng-Hua Chen Hai-Bo Xie Ming-Shuai Huo Hui Wu Lian-Jie Li Zheng-Yi Jiang School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW2522Australia The Key Laboratory of Magnetic and Electric Functional Materials and Applications of Shanxi Province Taiyuan University of Science and TechnologyTaiyuan030024China

In this study,the thermal expansion of Hf_(1-x)Ta_(x)Fe_(2)(x=0.10,0.13,0.15)compounds by adjusting the Ta concentration was successfully regulated.The magnetocaloric properties,hydrostatic pressure affecting the antiferromagnetic-ferromagnetic transition,and magnetostriction in the low magnetic field were studied.TheΔS_(M)values of 3.3 J·(kg-K)^(-1)and 3.6 J·(kg·K)^(-1)were obtained under magnetic fields of 10 kOe and 15 kOe in the Hf_(0.85)Ta_(0.15)Fe_(2),respectively.In the antiferromagnetic-ferromagnetic state transformation process under hydrostatic pressure up to 0.8 GPa,the state temperature does not decrease in a strictly linear manner.Outstanding magnetostrictive properties of 0.12%were obtained at a magnetic field of 10 kOe.This kind of alloy is supposed to be controlled under hydrostatic pressure to obtain good magnetic refrigeration performance and magnetostrictive properties.

关键词： Magnetoelastic transition Magnetocaloric effect hydrostatic pressure Hf1-xTaxFe2 compounds Magnetostriction

Restoration of Ultimate Strength of Dented Hemispheres Under External hydrostatic pressure

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China Ocean Engineering 2022年第3期36卷 500-507页

作者： HUANG Chen ZHANG Jian WANG Fang DI Chen-yang School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Shanghai Engineering Research Center of Hadal Science and Technology Shanghai Ocean UniversityShanghai 201306China

This study aimed to restore the ultimate strength of dented stainless-steel hemispheres with a radius of 90 mm and a thickness of 0.86 mm.All of the hemispheres were subjected to external hydrostatic pressure.Small stainless-steel stiffened caps were used to eliminate the effect of indention on the ultimate strength.These caps had a radius of 36 mm,a thickness of 0.76 mm,and a height of 10.44 mm.Six hemispherical samples,including two intact hemispheres,two dented hemispheres without stiffening,and two dented hemispheres with stiffening,were prepared.Each hemi-sphere was geometrically measured for shape and thickness,hydrostatically tested for destruction,and numerically evaluated for comparison.The experimental and numerical data agreed well with each other.As a result,a spherical cap can effectively restore the ultimate strength of dented hemispheres under external hydrostatic pressure.The proposed restoration approach can be used to strengthen underwater pressure hulls with large local geometric imperfections.

关键词： hemisphere restoration ultimate strength hydrostatic pressure buckling

The role of hydrostatic pressure on the metal corrosion in simulated deep-sea environments—a review

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Journal of Materials Science & Technology 2022年第17期112卷 230-238页

作者： Rui Liu Li Liu Fuhui Wang Shenyang National Laboratory for Materials Science Northeastern UniversityNO.3-11 Wenhua RoadShenyang 110819China

This paper reviewed the corrosion behavior of metals in simulated deep-water environments and briefly discussed the effect of hydrostatic pressure on the different corrosion types for the active and the passive alloys.A consensus on the corrosion mechanism is that hydrostatic pressure accelerates the dissolution kinetics,changes the chemical compositions of the product layer or passive films,and promotes the adsorption of Cl^(-)on the metal surface.In addition,a newly-developed mechanism that hydrostatic pressure facilitates the dissolution process by thinning the electric double layer was reviewed,the synergistic effect of hydrostatic pressure and tensile stress on the stress corrosion cracking was discussed,and the modified coating with chemical bonding interface to prolong the service life in this environment was introduced.

关键词： Corrosion hydrostatic pressure Deep-sea environments

Buckling of composite cylindrical shells with ovality and thickness variation subjected to hydrostatic pressure

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Defence Technology（防务技术） 2022年第5期18卷 862-875页

作者： Zhun Li Ke-chun Shen Xin-hu Zhang Guang Pan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an710072China Key Laboratory for Unmanned Underwater Vehicle Northwestern Polytechnical UniversityXi'an710072China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China

The initial geometric imperfection is one of the primary factors affecting the buckling behaviors of composite cylindrical shells under hydrostatic pressure.In this study,ovality and thickness variations as two representative types of the geometric imperfections are considered.After measuring the geometric imperfections,a typical carbon fiber reinforced polymers(CFRP)cylindrical shell is tested to obtain the buckling pressure.The buckling behaviors of the shell sample are analyzed in combination with the strain responses.By using the nonlinear numerical analysis,the buckling shapes of the CFRP cylinder shells with different combinations of ovality and thickness variation are firstly discussed.The rules of influence of such imperfections on the buckling pressure are then obtained by nonlinear regression method.Finally,an empirical formula is proposed to predict the buckling pressure of the composite cylinder shells,and the calculated results from the formula are in good agreement with the numerical results.

关键词： Composite Cylindrical shell Buckling hydrostatic pressure Imperfections

Optical properties of Al_(x)Ga_(1-x)As/GaAs Woods-Saxon quantum well in the presence of hydrostatic pressure and applied electric field

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Communications in Theoretical Physics 2022年第6期74卷 143-151页

作者： Zhi-Hai Zhang Yi-Sheng Shi Jian-Hui Yuan School of Physics and Electronics Yancheng Teachers UniversityYancheng 224002China Intelligent photoelectric device and measurement engineering research center Yancheng Teachers UniversityYancheng 224002China The Laboratory of Biomedical Photonics and Engineering Guangxi Medical UniversityNanning 530021China

The third harmonic generation(THG),linear and nonlinear optical absorption coefficients(OACs),and refractive index changes(RICs)are investigated in a Woods-Saxon quantum well(QW)modulated by the hydrostatic pressure and applied electric field.The effect of non-uniform aluminum doping(position-dependent effective mass(PDEM))on the mass of the system is discussed,and further to explore the influence of PDEM on the nonlinear THG,OACs,and RICs of the Woods-Saxon QW.These nonlinear optical properties above are obtained using the compact-density matrix formalism.The electron states in a Woods-Saxon QW under the constant effective mass(CEM)and PDEM are calculated by solving the Schr?dinger equation via the finite difference technique.The contributions from competing effects of the hydrostatic pressure and applied electric field to the nonlinear optical properties with CEM and PDEM are reported,as well as the comparison with each other.The observations reveal that the regulation of external fields and the influence of PDEM play an important role in the photoelectric properties of QW.

关键词： optical properties position dependent effective mass hydrostatic pressure electric field

Inhibition on Apoptosis Induced by Elevated hydrostatic pressure in Retinal Ganglion Cell-5 via Laminin Upregulating β1-integrin/Focal Adhesion Kinase/Protein Kinase B Signaling Pathway

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Chinese Medical Journal 2016年第8期129卷 976-983页

作者： Yi Li Yan-Ming Chen Ming-Ming Sun Xiao-Dan Guo Ya-Chen Wang Zhong-Zhi Zhang Department of Ophthalmology First Affiliated Hospital China Medical University Shenyang Liaoning 110001 China

Background：Glaucoma is a progressive optic neuropathy characterized by degeneration of neurons due to loss of retinal ganglion cells （RGCs）.High intraocular pressure （HIOP）,the main risk factor,causes the optic nerve damage.However,the precise mechanism of HIOP-induced RGC death is not yet completely understood.This study was conducted to determine apoptosis of RGC-5 cells induced by elevated hydrostatic pressures,explore whether laminin is associated with apoptosis under pressure,whether laminin can protect RGCs from apoptosis and affirm the mechanism that regulates the process of RGCs survival.Methods：RGC-5 cells were exposed to 0,20,40,and 60 mmHg in a pressurized incubator for 6,12,and 24 h,respectively.The effect of elevated hydrostatic pressure on RGC-5 cells was measured by Annexin V-fluorescein isothiocyanate/propidium iodide staining,3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide assay,and Western blotting of cleaved caspase-3 protein.Location and expression oflaminin were detected by immunofluorescence.The expression of β 1-integrin,phosphorylation of focal adhesion kinase （FAK） and protein kinase B （PKB,or AKT） were investigated with real-time polymerase chain reaction and Western blotting analysis.Results：Elevated hydrostatic pressure induced apoptosis in cultured RGC-5 cells.pressure with 40 mmHg for 24 h induced a maximum apoptosis.Laminin was declined in RGC-5 cells after exposing to 40 mmHg for 24 h.After pretreating with laminin,RGC-5 cells survived from elevated pressure.Furthermore,β1-integrin and phosphorylation of FAK and AKT were increased compared to 40 mmHg group.Conclusions：The data show apoptosis tendency of RGC-5 cells with elevated hydrostatic pressure.Laminin can protect RGC-5 cells against high pressure via β 1-integrin/FAK/AKT signaling pathway.These results suggest that the decreased laminin of RGC-5 cells might be responsible for apoptosis induced by elevated hydrostatic pressure,and laminin or activating β1-integrin/FAK/AKT pathway might be potential treatments to p

关键词： Apoptosis Glaucoma hydrostatic pressure Laminin Retinal Ganglion Cells

Single cell transcriptomic analysis identifies novel vascular smooth muscle subsets under high hydrostatic pressure

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Science China(Life Sciences) 2021年第10期64卷 1677-1690页

作者： Zhenzhen Chen Haizeng Zhang Yingnan Bai Changting Cui Shuangyue Li Wenjie Wang Yue Deng Qiannan Gao Lu Wang Wei Qi Lijun Zhang Yan Yang Bin Geng Jun Cai Hypertension Center Department of Cardiac SurgeryFuwai HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeState Key Laboratory of Cardiovascular DiseaseNational Center for Cardiovascular DiseasesBeijing 100191China Novogene Bioinformatics Technology Co. Ltd.Beijing 100015China

Although some co-risk factors and hemodynamic alterations are involved in hypertension progression,their direct biomechanical effects are unclear.Here,we constructed a high-hydrostatic-pressure cell-culture system to imitate constant hypertension and identified novel molecular classifications of human aortic smooth muscle cells(HASMCs)by single-cell transcriptome analysis.Under 100-mmHg(analogous to healthy human blood pressure)or 200-mmHg(analogous to hypertension)hydrostatic pressure for 48 h,HASMCs showed six distinct vascular SMC(VSMC)clusters according to differential gene expression and gene ontology enrichment analysis.Especially,two novel HASMC subsets were identified,named the inflammatory subset,with CXCL2,CXCL3 and CCL2 as markers,and the endothelial-function inhibitory subset,with AKR1C2,AKR1C3,SERPINF1 as markers.The inflammatory subset promoted CXCL2&3 and CCL2 chemokine expression and secretion,triggering monocyte migration;the endothelial-function inhibitory subset secreted SERPINF1 and accelerated prostaglandin F2αgeneration to inhibit angiogenesis.The expression of the two VSMC subsets was greatly increased in arterial media from patients with hypertension and experimental animal models of hypertension.Collectively,we identified high hydrostatic pressure directly driving VSMCs into two new subsets,promoting or exacerbating endothelial dysfunction,thereby contributing to the pathogenesis of cardiovascular diseases.

关键词： single cell RNA-seq hypertension VSMCs hydrostatic pressure

Influence of optical phonons on the electronic mobility in a strained wurtzite AlN/GaN heterojunction under hydrostatic pressure

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Journal of Semiconductors 2009年第8期30卷 4-9页

作者：周晓娟班士良 Department of Physics School of Physical Science and TechnologyInner Mongolia University

A variational method combined with solving the force balance equation is adopted to investigate the influence of strain and hydrostatic pressure on electronic mobility in a strained wurtzite AlN/GaN heterojunction by considering the scattering of optical-phonons in a temperature ranges from 250 to 600 K. The effects of conduction band bending and an interface barrier are also considered in our calculation. The results show that electronic mobility decreases with increasing hydrostatic pressure when the electronic density varies from 1.0 × 1012 to 6.5 × 1012 cm-2. The strain at the heterojunction interface also reduces the electronic mobility, whereas the pressure influence becomes weaker when strain is taken into account. The effect of strain and pressure becomes more obvious as temperature increases. The mobility first increases and then decreases significantly, whereas the strain and hydrostatic pressure reduce this trend as the electronic density increases at a given temperature （300 K）. The results also indicate that scattering from half space phonon modes in the channel side plays a dominant role in mobility.

关键词： hydrostatic pressure strained AlN/GaN heterojunction electronic mobility optical-phonon scattering