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Effects of Nb content in Ti–Ni–Nb brazing alloys on the microstructure and mechanical properties of Ti–22Al–25Nb alloy brazed joints

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Journal of Materials Science & Technology 2017年第7期33卷 682-689页

作者： Y.Wang x.Q.Cai Z.W.Yang D.P.Wang x.g.liu Y.C.liu Key Lab of Aclvanced Joining Technology School of Materials Science and Engineering Tianjin University Tiandin 300072 China

Vacuum brazing was successfully used to join Ti-22Al-25Nb alloy using Ti-Ni-Nb brazing alloys prepared by arc-melting. The influence of Nb content in the Ti-Ni-Nb brazing alloys on the interfacial microstructure and mechanical properties of the brazed joints was investigated. The results showed that the interfacial microstructure of brazed joint consisted of B2, O, ？3, and Ti2 Ni phase, while the width of brazing seams varied at different Nb contents. The room temperature shear strength reached359 MPa when the joints were brazed with eutectic Ti40Ni40Nb20 alloy at 1180？C for 20 min, and it was321, 308 and 256 MPa at 500, 650 and 800？C, respectively. Cracks primarily initiated and propagated in ？3compounds, and partially traversed B2＋O region. Moreover, the fracture surface displayed typical ductile dimples when cracks propagated through B2＋O region, which was favorable for the mechanical properties of the brazed joint.

关键词： Ti-22Al-25Nb alloy Ti-Ni-Nb brazing alloy Nb content Microstructure Mechanical properties

INVESTIgATION ON FRACTURE BEHAVIOR FOR WELDED JOINT OF NEW gENERATION FINE gRAINED STEEL SS400

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Acta Metallurgica Sinica(English Letters) 2003年第1期16卷 35-40页

作者： H.Y.Jing x.g.liu Z.Q.Zhu L.x.Huo Y.F.Zhang School of Materials Science and Engineering Tianjin University Tianjin 300072 China

The fracture behavior for welded joint of new generation fine grained steel SS400 was investigated and assessed on the basis of fitness for purpose philosophy. The actual critical defect sizes for the SS400 base metal and its weld HAZ (heat affected zone) defined by the gross yielding criterium have been determined directly by means of wide plate tests. It has been shown that although the HAZ grain growth occurs due to the welding heat, the resistance to fracture is not deteriorated. The deformation behavior of wide plate specimen was also studied by finite, element (FE) analysis. The deformation of weld HAZ is protected by the high strength weld metal, so it is easier to get the general yielding for the welded joint specimen.

关键词： fine grained steel general yielding wide plate test fracture behavior

STUDY ON DYNAMIC PERFORMANCE OF THE HYDRAULIC OIL

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STUDY ON DYNAMIC PERFORMANCE OF THE HYDRAULIC OIL

Biocontrol Potential of Chaetomium spirale ND35 against Canker of Apple Tree

第五届振动工程及其机械技术国际会议

作者： x.g.liu~a C.B.Chu~b a College of Energy and Power Engineering.Huazhong University of Science and Technology, Wuhan,430074,P.R.China b Nanchang Institute of Technology,Nanchang 330099 P.R China

＜正＞The hydraulic system performance is influenced by dynamic performance of hydraulic oil under working conditions *** this paper,for the non-linear properties of the mixture of pure hydraulic oil and air,the authors constructed the interrelationship of the various parameters of the fluid using state equation form and constructed the mixture effective density as a function of the pressure,temperature and the air content in fluid,created a mathematical analysis model,calculated the fluid bulk modulus with different air *** graphical compute results show the main factors which affect the fluid effective density and bulk modulus change,which also provide the engineers and technicians a more direct-viewing reference,thus for them designing accurate hydraulic systems model and carrying on dynamic analysis lay the foundation.

关键词： hydraulic oil non-linear dynamic performance

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Biocontrol Potential of Chaetomium spirale ND35 against Cank...

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

第一届国际生物防治与生物技术研讨会

作者： K.x.gao~1 x.g.liu~(1*) C.Li~2 Q.H.Wang~2 B.L.He~3 and Z.M.Yan~1 1 Department of Phytopathology Shandong Agricultural University Tai’an 271018 P.R.China 2 guanghuasi Tree Farm in Mountain Culai of Tai’an City Tai’an 271000 P.R. China 3 College of Science and Technology Shandong Agricultural University Tai’an 271018 P.R.China

＜正＞The biocontrol potential of Chaetomium spirale ND35 against the Valsa Canker of apple tree was preliminarily *** results of dual culture on PDA plate showed *** ND35 showed strong antagonism against Valsa ceratosperma;the inhibition zone in the interaction area of the two colonies of *** and *** ND35 was observed;the crude extract of culture in Corn Steep Powder Broth was able to inhibit the mycelial growth of *** more effectively than that one in MEB（Malt Extract Broth）.The results of biocontrol in greenhouse and in the field indicated that the disease incidence of apple tree of the treatment with *** ND35 was lower significantly than other treatments,including treatment with *** alone,scald and healthy *** reisolation experiment suggested that C. spirale ND35 could colonize in stems and branches of apple trees successfully and the ND35 colonization rate of the treatment with solid wheat bran culture was at higher level than the corn steep powder *** the biocontrol effect in the field of liquid culture was better than the solid culture.

关键词： Chaetomium spirale apple tree canker antagonism biocontrol

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Journal of Energy Chemistry 2025年第1期100卷 509-521页

作者： xinyuan Wang Fan Zhang xingyu Zhou Qian Wang Changyu liu Yangyang liu Hui Wang xiaojie liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode

Role of the greenland Sea ice anomaly in the late-spring drought over Northwest China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 1-5页

作者： Yang liu Huopo Chen Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University for Information Science and TechnologyNanjingChina

Drought across Northwest China in late spring has exerted a vital effect on the local climate and agricultural production,and has been alleviated during the past *** study explored the influence of the preceding Arctic sea ice on the May drought in Northwest China caused by the precipitation *** analysis indicated that when the greenland Sea ice concentration is abnormally high during February to April,the dry conditions in Northwest China tend to be *** increase of sea ice in the greenland Sea can excite a meridional circulation,which causes sea surface temperature(SST)anomalies in the North Atlantic via the sea-air interaction,manifested as significant warm SST anomalies over the south of greenland and the subtropical North Atlantic,but negative SST anomalies over the west of the *** abnormal SST pattern maintains to May and triggers a zonal wave train from the North Atlantic through Scandinavia and Central Asia to Northwest China,leading to abnormal cyclones in Northwest ***,Northwest China experiences a more humid climate than usual.

关键词： Arctic sea ice greenland Sea North Atlantic SST Drought Northwest China

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren Yu guoshu gao Yumeng Zhao xiongfu Zhang guodong liu guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen Qiong liu College of Chemistry and Materials Engineering Wenzhou University guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization

Interconnections between diabetic corneal neuropathy and diabetic retinopathy:diagnostic and therapeutic implications

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Neural Regeneration Research 2025年第8期20卷 2169-2180页

作者： Mingyi Yu Faith Teo En Ning Chang liu Yu-Chi liu Tissue Engineering and Stem Cell group Singapore Eye Research InstituteSingapore Yong Loo Lin School of Medicine National University of SingaporeSingapore Department of Cornea and External Eye Disease Singapore National Eye CenterSingapore Ophthalmology and Visual Sciences Academic Clinical Program Duke-NUS Medical SchoolSingapore

Diabetic corneal neuropathy and diabetic retinopathy are ocular complications occurring in the context of diabetes *** corneal neuropathy refers to the progressive damage of corneal *** retinopathy has traditionally been considered as damage to the retinal ***,growing evidence suggests that diabetic retinopathy is a complex neurovascular disorder resulting from dysfunction of the neurovascular unit,which includes both the retinal vascular structures and neural *** retinopathy is one of the leading causes of blindness and is frequently screened for as part of diabetic ocular ***,diabetic corneal neuropathy is commonly overlooked and underdiagnosed,leading to severe ocular surface *** studies have found that these two conditions tend to occur together,and they share similarities in their pathogenesis pathways,being triggered by a status of chronic *** review aims to discuss the interconnection between diabetic corneal neuropathy and diabetic retinopathy,whether diabetic corneal neuropathy precedes diabetic retinopathy,as well as the relation between the stage of diabetic retinopathy and the severity of corneal *** also endeavor to explore the relevance of a corneal screening in diabetic eyes and the possibility of using corneal nerve measurements to monitor the progression of diabetic retinopathy.

关键词： cornea corneal nerves diabetes diabetic corneal neuropathy diabetic retinopathy retina