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甘氨酸螯合亚铁对断奶仔猪组织矿物质水平、粪中矿物质浓度、肝脏抗氧化酶活性的影响

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饲料与畜牧（新饲料） 2014年第6期 52-56页

作者： J.Feng W.Q.Ma z.r.xu J.X.He Y.z.Wang J.X.Liu 吉隆达集团技术中心四川广汉618300

24头断奶仔猪用于评估甘氨酸螯合亚铁（Fe-Gly）对组织矿物质水平、粪便矿物质浓度及肝脏抗氧化酶活性的影响。根据活体重和来源将仔猪分配到6个处理组。处理组：①对照组（不补充铁）;②铁：30mg/kg（Fe-Gly）;③铁：60mg/kg（Fe-Gly）... 详细信息

24头断奶仔猪用于评估甘氨酸螯合亚铁（Fe-Gly）对组织矿物质水平、粪便矿物质浓度及肝脏抗氧化酶活性的影响。根据活体重和来源将仔猪分配到6个处理组。处理组：①对照组（不补充铁）;②铁：30mg/kg（Fe-Gly）;③铁：60mg/kg（Fe-Gly）;④铁：90mg/kg（Fe-Gly）;⑤铁：120mg/kg（Fe-Gly）;⑥正对照组,铁：120mg/kg（FeSO4）。连续40d补充Fe-Gly：心脏（P〈0.05）、肝脏（P〈0.05）、肾脏（P〈0.05）、脾脏（P〈0.05）及粪便（P〈0.01）中铁的浓度增加。以Fe-Gly形式补充0~120mg/kg铁：肝脏和肾脏中铁浓度成线性增加。与对照组相比,补充FeSO4增加心脏、肝脏、脾脏和粪便中铁的浓度（P〈0.05或P〈0.01）。以FeSO4和Fe-Gly补铁120mg/kg,Fe-Gly组仔猪脾脏中铁浓度增加（P=0.01）,粪便中铁浓度略有降低（P=0.09）。过氧化氢酶和琥珀酸脱氢酶（SDH）的活性与补充的Fe-Gly成线性反应趋势。与负对照组相比,以Fe-Gly形式补铁90mg／kg可增加SOD（P=0．02）和SDH（P=0．03）活性。然而，胰腺中矿物质浓度，粪铜、锌、锰浓度以及肝脏黄嘌呤氧化酶活性在各处理组间没有显著差异（P≥0．05）。

关键词： Fe-Gly 组织粪便抗氧化酶断奶仔猪

Pinless Friction Stir Spot Welding of Mg-3Al-1zn Alloy with zn Interlayer

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Journal of Materials Science & Technology 2016年第1期32卷 76-88页

作者： r.z.xu D.r.Ni Q.Yang C.z.Liu z.Y.Ma College of Materials Science and Engineering Shenyang Aerospace University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

With the addition of a thin zn interlayer, 2.4 mm thick Mg-3AI-1zn alloy sheets were friction stir spot welded （FSSW） using a pinless tool with fiat, convex and concave shoulder shapes. The results showed that an alloying reaction took place between the Mg substrate and zn interlayer during FSSW, forming a discontinuous intermetallics layer composed of dispersive （α-Mg ＋ Mgzn） eutectic structure under- neath the shoulder and a Mg-zn intermetallics bonding zone at the outside of the joints. This alloying reaction increased the bonded area and eliminated the hook defects, thereby producing sound FSSWjoints with a shallow keyhole without hook defects. The increase of plunge depth was beneficial to the Mg-zn diffusion, thereby increasing the tensile-shear load of the joints. However, excessive plunge depths re- sulted in a decrease of the effective sheet thickness, reducing the strength of the joints. At a small plunge depth, the convex and concave shoulders were more beneficial to the interface reaction than the fiat shoul- der. The maximum joint load of 6.6 kN was achieved by using the concave shoulder at a plunge depth of 1.0 mm. A post-welding heat treatment promoted the dissolution of the discontinuous reaction layer in the joints; however, it led to the occurrence of void defects, influencing the bonding strength.

关键词： Friction stir spot welding Magnesium alloys zn interlayer Hook defects

Influencing mechanism of pre-existing nanoscale Al5Fe2 phase on Mg-Fe interface in friction stir spot welded Al-free zK60-Q235 joint

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Journal of Materials Science & Technology 2020年第7期42卷 220-228页

作者： r.z.xu Q.Yang D.r.Ni B.L.Xiao C.z.Liu z.Y.Ma Institute of Metal research Chinese Academy of SciencesShenyang110016China College of Material Science and Engineering Shenyang Aerospace UniversityShenyang110136China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign1304 W Green StUrbanaIL61801United States Fredrick Seitz Materials research Laboratory University of Illinois at Urbana-Champaign104 S Goodwin AveUrbanaIL61801United States

Al-free zK60 magnesium (Mg) alloy sheet was selected as substrate material of Mg-steel pinless friction stir spot welding (FSSW), avoiding the effect of the Al element in the substrate on the alloying reaction of Mg-iron (Fe) interface. The sound FSSW joint of zK60 Mg alloy and Q235 steel with a hot-dipped aluminum (Al)-containing zinc (zn) coating was successfully realized. The detailed microstructural examinations proved that Al5Fe2 phase at the Mg-Fe interface came from the pre-existing Al5Fe2 phase in the coating and acted as the transition layer for promoting the metallurgical bonding of Mg and Fe. The interfaces with well-matched lattice sites among Fe, Al5Fe2 and Mg were formed during FSSW. A low energy interface with good match of lattice sites ((002)Al5Fe2//(110)Fe, [110]Al5Fe2//[113]Fe) between Al5Fe2 and Fe was identified. For the interface between Al5Fe2 and Mg, an orientation relationship of (622)Al5Fe2//(3112)Mgand[158]Al5Fe2//[2423]Mg was observed. The tensile-shear load of the zK60-steel joint could reach 4.6 kN. Moreover, the joint fracture occurred at the interface between the Al5Fe2 layer and the Mg alloy substrate, suggesting the brittle fracture characteristic.

关键词： Dissimilar welding Friction stir spot welding Magnesium alloys Steels zinc coating

Intrinsic Strength Asymmetry Between Tension and Compression of Perfect Face-Centered-Cubic Crystals

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Acta Metallurgica Sinica(English Letters) 2016年第8期29卷 755-762页

作者： r.F.Wang J.xu r.T.Qu z.Q.Liu z.F.zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

The strength asymmetry between tension and compression is a typical case of mechanical response of *** we achieve the intrinsic strength asymmetry of six face-centered-cubic perfect crystals（Cu,Au,Ni,Pt,Al and Ir）through calculating the ideal tensile and compressive strength with considering the normal stress effect and the competition between different crystallographic *** results show that both the intrinsic factors（the ideal shear strength and cleavage strength of low-index planes）and the orientation could affect the strength asymmetry,which may provide insights into understanding the strength of ultra-strong materials.

关键词： Perfect crystal Strength asymmetry Tension Compression

Structural Damage Detection Using a Modified Artificial Bee Colony Algorithm

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Computer Modeling in Engineering & Sciences 2016年第4期111卷 335-355页

作者： H.J.xu z.H.Ding z.r.Lu J.K.Liu Department of Mechanics Sun Yat-sen UniversityGuangzhou 510006China

An optimization approach based on Artificial Bee Colony(ABC)algorithm is proposed for structural local damage detection in this *** objective function for the damage identification problem is established by structural parameters and modal assurance criteria(MAC).The ABC algorithm is presented to solve the certain objective *** the Tournament Selection Strategy and chaotic search mechanism is adopted to enhance global search ability of the certain algorithm.A coupled double-beam system is studied as numerical example to illustrate the correctness and efficiency of the propose *** simulation results show that the modified ABC algorithm can identify the local damage of the structural system efficiently even under measurement noise,which demonstrates the proposed algorithm has a higher damage diagnosis precision.

关键词： structural damage detection Artificial Bee Colony algorithm Modal Assurance Criteria coupled double-beam system Tournament Selection Strategy

STUDY ON PrOPErTIES OF PULSE ELECTrODEPOSITED rE-Ni-W-P-SiC COMPOSITE COATINGS

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Acta Metallurgica Sinica(English Letters) 2007年第2期20卷 111-116页

作者： z.C. Guo X.Y. zhu r.D. xu Faculty of Materials and Metallurgical Engineering Kunming University of Science and Technology Kunming 650093 China

The effects of pulse frequency f and duty cycle r on the deposition rate, composition, morphology, and hardness of pulse electrodeposited rE （rare earth）-Ni-W-P-SiC composite coatings have been studied. The results indicate that pulse current can improve the deposition rate of rE-Ni-W-P-SiC composite coatings; W, P, and SiC contents in the coating decrease with the increase of pulse frequency and reach the lowest value at f = 33Hz, whereas the rE content in the composite coatings increases with the increase of pulse frequency. SiC content decreases with the increase of duty cycle, W content reaches the lowest value, and P content reaches the highest value at r = 0.4; pulse current and rE can lead to smaller size of the crystalline grains; however, the effects of different pulse frequency and duty cycle on the morphologies of rE-Ni-W-P-SiC composite coatings are not obvious. The hardness of rE-Ni-W-P-SiC composite coatings is the highest when the duty cycle is at 0.6 and 0.8 and pulse frequency is at 50Hz. At the same pulse frequency, the hardness of rE-Ni-W-P-SiC composite coatings at r= 0.8 is higher than that at r= 0.6.

关键词： frequency duty cycle electrodeposition rE-Ni-W-P-SiC composite coating

Silicon prepared by electro-reduction in molten salts as new energy materials

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Journal of Energy Chemistry 2020年第8期29卷 46-61,I0002页

作者： Tingting Jiang Xinyi xu George z.Chen The State Key Laboratory of refractories and Metallurgy College of Materials and MetallurgyWuhan University of Science and TechnologyWuhan 430081HubeiChina Electrochemical Technologies Group Faculty of EngineeringUniversity of NottinghamNottingham NG27RDUK Electrochemical Technologies Group Faculty of Science and EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100ZhejiangChina

Silicon has a large impact on the energy supply and economy in the modern world. In industry, high purity silicon is firstly prepared by carbothermic reduction of silica with the produced raw silicon being further refined by a modified Siemens method. This process suffers from the disadvantages of high cost and contaminant release and emission. As an alternative, the molten salt electrolysis approach, particularly the FFC Cambridge Process(FFC: Fray-Farthing-Chen), could realize high purity silicon products with morphology-controllable nanostructures at low or mild temperatures(generally 650–900 ℃). In this article, we review the development, reaction mechanisms, and electrolysis conditions of silicon production by the FFC Cambridge Process. Applications of the silicon products from electrolysis in molten salts are also discussed in terms of energy applications, including using them as the photovoltaic element in solar cells and as the charge storage phase in the negative electrode(negatrode) of lithium ion batteries.

关键词： Electrolysis Molten salt Silicon Nanomaterial Li ion battery Solar cell

Demystifying Mechanosensitive Piezo Ion Channels

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Neuroscience Bulletin 2016年第3期32卷 307-309页

作者： X.z.Shawn xu Life Sciences Institute and Department of Molecular and Integrative Physiology University of Michigan

Mechanosensitive channels mediate touch,hearing,proprioception,and blood pressure *** proteins,including Piezo1 and Piezo2,represent a new class of mechanosensitive channels that have been reported to play key roles in most,if not all,of these *** structural architecture and molecular mechanisms by which Piezos act as mechanosensitive channels,however,remain *** new studies have now provided critical insights into the atomic structure and molecular basis of the ion permeation and mechano-gating properties of the Piezo1 channel.

关键词： Mechanosensation Mechanosensory echanotransduction Mechanical Cryo-EM Piezo

Peripheral blood rNA biomarkers can predict lesion severity in degenerative cervical myelopathy

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Neural regeneration research 2025年第6期20卷 1764-1775页

作者： zhenzhong zheng Jialin Chen Jinghong xu Bin Jiang Lei Li Yawei Li Yuliang Dai Bing Wang Department of Spine Surgery The Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse *** numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical *** study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic *** analysis identified 128 differentially expressed genes that were enriched in patients with neurological *** least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,*** of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%*** results suggest that peripheral blood rNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

关键词： biomarkers candidate genes degenerative cervical myelopathy gene expression analysis immune cell types neurological disabilities peripheral blood rNA profiles spinal cord injury