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Improving corrosion resistance of additively manufactured WE43 magnesium alloy by high temperature oxidation for biodegradable applications

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Journal of Magnesium and Alloys 2024年第3期12卷 940-953页

作者： Jinge Liu Bangzhao Yin fei song Bingchuan Liu Bo Peng Peng Wen Yun Tian Yufeng Zheng Xiaolin Ma Caimei Wang State Key Laboratory of Tribology in Advanced Equipment Beijing100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Department of Orthopaedics Beijing Tsinghua Changgung HospitalInstitute for Precision MedicineTsinghua UniversityBeijing102218China Department of Orthopaedics Peking University Third HospitalBeijing 100191China Engineering Research Center of Bone and Joint Precision Medicine Ministry of EducationBeijing 100191China School of Materials Science and Engineering Peking UniversityBeijing 100871China Beijing AKEC Medical Co. Ltd.Beijing 102200China

Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid *** this work,dense WE43 L-PBF samples were built with the relativity density reaching 99.9%.High temperature oxidation was performed on the L-PBF samples in circulating air via various heating temperatures and holding *** oxidation and diffusion at the elevated temperature generated a gradient structure composed of an oxide layer at the surface,a transition layer in the middle and the *** oxide layer consisted of rare earth(RE)oxides,and became dense and thick with increasing the holding *** matrix was composed ofα-Mg,RE oxides and Mg_(24)RE_(5) *** precipitates almost disappeared in the transition *** passivation effect was observed in the samples treated by a suitable high temperature *** original L-PBF samples lost 40%weight after 3-day immersion in Hank’s solution,and broke into fragments after 7-day *** casted and solution treated samples lost roughly half of the weight after 28-day *** high temperature oxidation samples,which were heated at 525℃ for 8 h,kept the structural integrity,and lost only 6.88%weight after 28-day *** substantially improved corrosion resistance was contributed to the gradient structure at the *** one hand,the outmost dense layer of RE oxides isolated the corrosive medium;on the other hand,the transition layer considerably inhibited the corrosion owing to the lack of ***,high temperature oxidation provides an efficient,economic and safe approach to inhibit the corrosion of WE43 L-PBF samples,and has promising prospects for future clinical applications.

关键词： Laser powder bed fusion Biodegradable magnesium alloy High temperature oxidation Corrosion resistance WE43.

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Comparison of the Coronal Green-line Intensities with the EUV Measurements from SDO/AIA

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Research in Astronomy and Astrophysics 2022年第7期22卷 191-205页

作者： Xue-fei Zhang Yu Liu Ming-Yu Zhao Ji-Hong Liu Abouazza Elmhamdi Teng-fei song Zi-Han Li Hong-Bo Li fei-Yang Sha Jing-Xing Wang Xiao-Bo Li Yuan-Deng Shen Shun-Qing Liu Hong-fei Liang R.M.Al-Shammari Yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Shijiazhuang University Shijiazhuang 050035China School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China Department of Physics and Astronomy King Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia Yunnan Normal University School of Physics and Electronic InformationKunming 650500China Institute of Space Physics Luoyang Normal UniversityLuoyang 471934China

The intensity of the green line(Fe ⅩⅣ 5303 A) is the strongest in the visible spectrum of the solar corona,and this line has been used as long-term powerful diagnostic tools for studying the coronal configurations and hot plasma ***,it remains unclear and an open question whether there exists close relationship between the green line intensities and the coronal extreme ultraviolet(EUV) line emissions for various coronal *** this paper,we use the green-line data by the Lijiang YOGIS Lyot coronagraph and the EUV data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly instruments in order to perform direct comparisons and analyses,based on two algorithms developed to extract particular features in the low *** is found that,among the correlation coefficients obtained between the intensities of 5303 A and the EUV lines,the coefficients between the green line and the 211 A wavelength for different coronal structures and different limb locations always keep the highest values(ranging from 0.89 to 0.99),which has not been reported *** result can be helpful and promising to link together the various physical processes involved at different heights in the corona by precisely tracking the bright loops or other features observed in 5303 A above the limb down to the correct surface locations revealed by the 211 A ***,the ground-based observations of the coronal green line and the space-based EUV observations at 211 A can advantageously complement each other when there is a need.

关键词： Sun:corona Sun:magnetic fields stars:coronae

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A Preconditioned Multigrid Method for Efficient Simulation of Three-dimensional Compressible and Incompressible Flows

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Chinese Journal of Aeronautics 2007年第4期20卷 289-296页

作者： Han Zhonghua He fei song Wenping Qiao Zhide National Key Laboratory of Aerodynamic Design and Research School of Aeronautics Northwestern Polytechnical University Xi ＇an 710072 China

To develop an efficient and robust aerodynamic analysis method for numerical optimization designs of wing and complex configuration, a combination of matrix preconditioning and multigrid method is presented and investigated. The time derivatives of three-dimensional Navier-Stokes equations are preconditioned by Choi-Merkle preconditioning matrix that is originally designed for two-dimensional low Mach number viscous flows. An extension to three-dimensional viscous flow is implemented, and a method improving the convergence for transonic flow is proposed. The space discretizaition is performed by employing a finite-volume cell-centered scheme and using a central difference. The time marching is based on an explicit Rtmge-Kutta scheme proposed by Jameson. An efficient FAS multigrid method is used to accelerate the convergence to steady-state solutions. Viscous flows over ONERA M6 wing and M100 wing are numerically simulated with Mach numbers ranging from 0.010 to 0.839. The inviscid flow over the DLR-F4 wing-body configuration is also calculated to preliminarily examine the performance of the presented method for complex configuration. The computed results are compared with the experimental data and good agreement is achieved. It is shown that the presented method is efficient and robust for both compressible and incompressible flows and is very attractive for aerodynamic optimization designs of wing and complex configuration.

关键词： Navier-Stokes equations preconditioning method multigrid method numerical simulation

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Role of local coordination in bimetallic sites for oxygen reduction: A theoretical analysis

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Journal of Energy Chemistry 2020年第5期29卷 131-137页

作者： Yuqi Yang Hao Zhang Zhaofeng Liang Yaru Yin Bingbao Mei fei song Fanfei Sun songqi Gu Zheng Jiang Yuen Wu Zhiyuan Zhu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China Shanghai Synchrotron Radiation Facility Zhangjiang LaboratoryShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)University of Science and Technology of ChinaHefei 230026AnhuiChina ShanghaiTech University Shanghai 201210China

Understanding of the oxygen reduction reaction(ORR)mechanism for single atom catalysts is pivotal for the rational design of non-precious metal cathode materials and the commercialization of fuel ***,a series of non-precious metal electrocatalysts based on nitrogen-doped bimetallic(Fe and Co)carbide were modeled by density functional theory calculations to predict the corresponding reaction *** study elucidated prior oxygen adsorption on the Fe atom in the dual site and the modifier role of Co atoms to tune the electronic structures of *** reaction activity was highly correlated with the bimetallic center and the coordination environment of the adjacent ***,the preadsorption of*OH resulted in the apparent change of metal atoms'electronic states with the d-band center shifting toward the Fermi level,thereby boosting reaction *** result should help promote the fundamental understanding of active sites in ORR catalysts and provide an effective approach to the design of highly efficient ORR catalysts on an atomic scale.

关键词： Non-precious metal catalysts Bimetallic-sites Oxygen reduction reaction Density functional theory

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Understanding the synergetic interaction within α-MoC/β-Mo2C heterostructured electrocatalyst

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Journal of Energy Chemistry 2019年第8期28卷 66-70,I0004页

作者： Hao Zhang Haiyan Jin Yuqi Yang Fanfei Sun Yang Liu Xianlong Du Shuo Zhang fei song Jianqiang Wang Yong Wang Zheng Jiang Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204 China University of Chinese Academy of Sciences Beijing 100100 China Advanced Materials and Catalysis Group Institute of Catalysis Zhejiang UniversityHangzhou 310028 Zhejiang China

Constructing heterostructure is an important strategy to design efficient electrocatalysts. The synergetic interaction between dissimilar materials has been considered as the origin of the activity enhancement,however, the interfacial interaction is challenging to probe, thus, the underlying mechanism remains obscure. Here, we reported a heterostructured α-MoC/β-Mo2 C electrocatalyst for hydrogen evolution in alkaline media, which shows a significant electrocatalytic activity improvement as compared to the single component. Based on extensive characterizations including high-resolution transmission electron microscopy and X-ray absorption fine structure(XAFS) spectroscopy, together with density functional theory, we unraveled the synergetic interaction between α-MoC and β-Mo2 C, implying that α-Mo C sites are beneficial for water dissociation and hydrogen prefers to release on β-Mo2 C sites.

关键词： Hydrogen evolution reaction Heterostructure Molybdenum carbide Synergetic interaction Water dissociation

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Combined detection of plasma GATA5 and SFRP2 methylation is a valid noninvasive biomarker for colorectal cancer and adenomas

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World Journal of Gastroenterology 2015年第9期21卷 2629-2637页

作者： Xie Zhang Yu-fei song Hong-Na Lu Dan-Ping Wang Xue-song Zhang Shi-Liang Huang Bei-Lei Sun Zhi-Gang Huang Department of Gastroenterology Ningbo Medical Treatment Center Li Huili Hospital School of Medicine Ningbo University Department of Gastroenterology Zhejiang Provincial People’s Hospital

AIM:To investigate GATA5,SFRP2,and ITGA4 methylation in plasma DNA as noninvasive biomarkers for colorectal cancer(CRC) or ***:There were 57 CRC patients,30 adenomas patients,and 47 control patients enrolled in this ***-specific polymerase chain reaction was used to determine the promoter methylation status of GATA5,SFRP2,and ITGA4 genes in plasma DNA,and their association with clinical outcome in *** predictive ability of GATA5,SFRP2,and ITGA4 methylation,individually or in combination,to detect CRC or adenomas was further ***:Hypermethylated GATA5 was detected in plasma in 61.4%(35/57) of CRC cases,43.33%(13/30) of adenoma cases,and 21.28%(10/47) of control *** hypermethylation of SFRP2 was detected in 54.39%(31/57),40.00%(12/30),and 27.66%(13/47) in plasma samples from CRC,adenomas,and controls,***4 methylation was detected in 36.84%(21/57) of plasma samples of CRC patients and in 30.00%(9/30) of plasma samples from patients with colorectal adenomas,and the specificity of this individual biomarker was 80.85%(9/47).Moreover,GATA5 methylation in the plasma was significantly correlated with larger tumor size(P =0.019),differentiation status(P =0.038),TNM stage(P =0.008),and lymph node metastasis(P =0.008).SFRP2 and ITGA4 methylation in plasma significantly correlated with differentiation status(SFRP2,P =0.012; ITGA4,P =0.007),TNM stage(SFRP2,P =0.034; ITGA4,P =0.021),and lymph node metastasis(SFRP2,P =0.034; ITGA4,P =0.021).From the perspective of predictive power and cost-performance,using GATA5 and SFRP2 together as methylation markers seemed the most favorable predictor for CRC(OR =8.06;95%CI:2.54-25.5; P < 0.01) and adenomas(OR =3.35; 95%CI:1.29-8.71; P =0.012).CONCLUSION:A combination of GATA5 and SFRP2 methylation could be promising as a marker for the detection and diagnosis of CRC and adenomas.

关键词： Colorectal cancer GATA binding protein 5 Secreted

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Zn（Ⅱ） can mediate self-association of the extracellular C-terminal domain of CD147

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Protein & Cell 2018年第3期9卷 310-315页

作者： Shujuan Jin Pengfei Ding Pengxiang Chu Hongwei Li Jianbo Sun Dehai Liang fei song Bin Xia Beijing Nuclear Magnetic Resonance Center Peking University Beijing 100871 China College of Chemistry and Molecular Engineering Peking University Beijing 100871 China School of Life Sciences Peking University Beijing 100871 China Cell Engineering Research Center and Department of Cell Biology State Key Laboratory of Cancer Biology The Fourth Military Medical University Xi'an 710032 China

CD147 （cluster of differentiation 147）, also known as basigin or extracellular matrix metalloproteinase inducer （EMMPRI N）, is a cell-surface type I transmembrane glycoprotein expressed at different levels in various cells and tissues, especially at high levels in tumor cells （Grass and Toole, 2015）. CD147 plays important roles in multiple physiological processes, such as spermatogenesis, neural network formation, T-cell activation and in the progression of several diseases including tumor metastasis rheumatoid arthritis （RA） atherosclerosis malaria and HIV infection （Muramatsu, 2016）.

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Unprecedented sesquiterpene-polycyclic polyprenylated acylphloroglucinol adduct against acute myeloid leukemia via inhibiting mitochondrial complex Ⅴ

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Chinese Chemical Letters 2024年第10期35卷 305-308页

作者： Zhengyi Shi Jie Yin Yang Xiao Zhangrong Hou fei song Jianping Wang Qingyi Tong Changxing Qi Yonghui Zhang Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science andTechnologyWuhan430030China

Monosescinol A(1),the first example of sesquiterpene–polycyclic polyprenylated acylphloroglucinol(PPAP)adduct,which represented a new subclass of PPAP-type natural products,along with two new congeners with normal spiro 6/6/5 tricyclic architecture,were isolated from Hypericum *** A possessed an unprecedented 6/5/5/6/6 pentacyclic carbon skeleton that might be assembled from the 6/6/5 carbon skeleton,via the splitting decomposition of C-3/C-14,and the attack from the C-3 in the PPAP core to C-28 in sesquiterpene *** addition,we have firstly confirmed that 24R configuration was existed in sec–Bu containing PPAPs by single crystal diffraction data analysis of monosescinol B(2),that might provide an enlightenment in the configurational determination of sec–Bu containing ***,further pharmacological research has found that compound 1 exhibited remarkable pharmacological effects against acute myeloid leukemia(AML)cell lines,with direct inhibition of mitochondrial complex V and an increase in mitochondrial membrane potential,and led to an induction of oxidative stress,endogenous inflammation,and apoptosis of AML cells.

关键词： PPAP adduct Single-crystal X-ray diffraction Keto-enol tautomerism Plausiblebiosynthetic pathway Cytotoxic activity

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RECONSTRUCTION OF THE SELLAR FLOOR FOLLOWING TRANSSPHENOIDAL SURGERY USING GELATIN FOAM AND FIBRIN GLUE

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Chinese Medical Sciences Journal 2005年第3期20卷 198-201页

作者： Jian Yin Chang-bao Su Zhi-qin Xu Xue-wei Xia fei song Department of Neurosurgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 Department of Neurosurgery the Second Affiliated Hospital Dalian Medical University Dalian 116027

Objective To introduce a new principle of sellar reconstruction and to evaluate the effectiveness of absorbable gelatin foam and fibrin glue for sellar reconstruction. Methods A total of 176 consecutive patients who underwent surgery for pituitary adenomas, cysts, chordomas, or subdiaphragmatic craniopharyngiomas in the sella turcica between January 2001 and April 2003 at Peking Union Medical College Hospital were enrolled. Different techniques of sellar closure and indications for each specific condition were retrospectively reviewed. Results Seventy-seven (43.7%) patients developed a visible cerebrospinal fluid (CSF) leakage during surgery. Intra- operative CSF leakage were repaired simply with gelatin foam and fibrin glue in 62 (35.2%) patients, and with autologous fat graft and sellar floor reconstruction in 15 (8.5%) patients. Postoperative CSF rhinorrhea occurred only in 1 case. There were no visual deterioration, allergic rhinitis, meningitis, pneumocranium, granulomas, or other complications asso- ciated with the reconstruction procedure. Conclusion The procedure of using gelatin foam and fibrin glue and principle of cranial base reconstruction is safe and effective in preventing postoperative complications following transsphenoidal surgery.

关键词： transsphenoidal surgery sellar floor reconstruction cerebrospinal fluid leakage

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Existence and Global Exponential Stability of Periodic Solutions for General Shunting Inhibitory Cellular Neural Networks with Delays

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Journal of Mathematical Research and Exposition 2010年第6期30卷 1125-1136页

作者： De fei ZHANG Xin song YANG Yao LONG Ping HE Department of Mathematics Honghe UniversityYunnan 661100P.R.China

By using the Leray-Schauder fixed point theorem,differential inequality techniques and constructing suitable Lyapunov functional,several sufficient conditions are obtained for the existence and global exponential stability of periodic solutions for general shunting inhibitory cellular neural networks with *** new results are obtained and some previously known results are *** example is employed to illustrate our feasible results.

关键词： shunting inhibitory cellular neural networks global exponential stability periodic solution.

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