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Tungsten 2025年第1期 120-136页

作者： Zao-ming Wu Lin He Lin-Sen Ye Xiao-Feng Yang jia-jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

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Research of Optical Fiber Coil Winding Model Based on Large-deformation Theory of Elasticity and Its Application

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Chinese Journal of Aeronautics 2011年第5期24卷 640-647页

作者： jia ming YANG Gongliu School of Instrumentation Science and Opto-electronics Engineering Beihang University Beijing 100191 China

Optical fiber coil winding model is used to guide proper and high precision coil winding for fiber optic gyroscope （FOG） application. Based on the large-deformation theory of elasticity, stress analysis of optical fiber free end has been made and balance equation of infinitesimal fiber is deduced, then deformation equation is derived by substituting terminal conditions. On condition that only axial tensile force exists, approximate curve equation has been built in small angle deformation scope. The comparison of tangent point longitudinal coordinate result between theory and approximation gives constant of integration, and expression with tangent point as origin of coordinate is readjusted. Analyzing the winding parameters of an example, it is clear that the horizontal distance from the highest point of wheel to fiber tangent point has millimeter order of magnitude and significant difference with fiber tension variation, and maintains invariant when wheel radius changes. The height of tension and accurate position of tangent point are defined for proper fiber guide. For application to fiber optic gyroscope, spiral-disc winding method and nonideal deformation of straddle section are analyzed, and then spiral-disc quadrupole pattern winding method has been introduced and realized by winding system. The winding results approve that the winding model is applicable.

关键词： fibers fiber optics large-deformation fiber optic gyroscope spiral-disc winding quadrupole pattern

Tool Wear and Its Effect on Surface Roughness in Diamond Cutting of Glass Soda-lime

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1224-1230页

作者： jia Peng ZHOU ming Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin 150001 China

For the technology of diamond cutting of optical glass, the high tool wear rate is a main reason for hindering the practical application of this technology. Many researches on diamond tool wear in glass cutting rest on wear phenomenon describing simply without analyzing the genesis of wear phenomenon and interpreting the formation process of tool wear in mechanics. For in depth understanding of the tool wear and its effect on surface roughness in diamond cutting of glass, experiments of diamond turning with cutting distance increasing gradually are carried out on soda-lime glass. The wear morphology of rake face and flank face, the corresponding surface features of workpiece and the surface roughness, and the material compositions of flank wear area are detected. Experimental results indicate that the flank wear is predominant in diamond cutting glass and the flank wear land is characterized by micro-grooves, some smooth crater on the rake face is also seen. The surface roughness begins to increase rapidly, when the cutting mode changes from ductile to brittle for the aggravation of tool wear with the cutting distance over 150 m. The main mechanisms of inducing tool wear in diamond cutting of glass are diffusion, mechanical friction, thermo-chemical action and abrasive wear. The proposed research makes analysis and research from wear mechanism on the tool wear and its effect on surface roughness in diamond cutting of glass, and provides theoretical basis for minimizing the tool wear in diamond cutting brittle materials, such as optical glass.

关键词： diamond cutting tool wear surface roughness soda-lime glass

Mechanism of action of Linggui Zhugan Decoction in treating non-alcoholic fatty liver disease using untargeted metabolomics approach

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Traditional Medicine Research 2025年第2期10卷 65-76页

作者： Huan Pei Ren-Lin Li Xin-Ran Song Qian-Qian Wan Yu-ming Wang Han-Zhou Li Wei-Quan Xu jia-Bao Liao Wei-Bo Wen Jing Miao Huan-Tian Cui School of Basic Medicine Yunnan University of Chinese MedicineKunming 650599China School Clinical Medical College Yunnan University of Chinese MedicineKunming 650599China First School of Clinical Medicine Yunnan University of Chinese MedicineKunming 650599China School of Integrative Chinese and Western Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Pharmacy Tianjin Second People's HospitalTianjin 300192China

Background:Non-alcoholic fatty liver disease(NAFLD)is a liver disorder characterized by the accumulation and degeneration of fat in the liver cells,a condition that may further deteriorate and lead to cirrhosis and liver *** studies showed that metabolic dysfunction can promote NAFLD *** Zhugan Decoction(LGZGD)has therapeutic effects on *** mechanism of LGZGD still remains *** study was to examine the impact of LGZGD on the metabolic processes involved in the development of ***:A mice model of NAFLD was treated with *** therapeutic potential of LGZGD was evaluated by assessing the activity of transaminases,lipids levels of blood,and pathological changes in the liver of the mice model of ***,this study also evaluated the influence of LGZGD on liver inflammation and oxidative ***:The results of untargeted metabolomics analysis showed that LGZGD reduced the disordered lipid metabolism in NAFLD *** improved the oxidative stress and also reduced the levels of pro-inflammatory cytokines in the *** metabolomics analysis of liver samples revealed that LGZGD treatment improved metabolic disorders,including alanine,aspartate,glutamate,glycerophospholipid metabolism,and citrate *** RT-qPCR and Western blot results showed that LGZGD could regulate the expression of key enzymes in the metabolic pathway of the citrate cycle,including ATP-citrate lyase(ACLY),alanine-glyoxylate aminotransferase-2(AGXT2),phosphatidylethanolamine N-methyltransferase(PEMT),and succinate dehydrogenase(SDH).Conclusion:We found that LGZGD can treat NAFLD by reducing inflammatory responses,inhibiting oxidative stress,regulating alanine,aspartate,glutamate,and glycerophospholipid metabolism,and citrate cycle pathways.

关键词： NAFLD LGZGD untargeted metabolomics glycerophospholipid metabolism citrate cycle

丹酚酸B调控脂质代谢改善非酒精性脂肪肝实验研究

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中国药理学通报 2025年第1期41卷 107-115页

作者：张佳健郭梦茹梅金玉陈明安徽医科大学基础医学院药理学教研室安徽合肥230032 安徽医科大学第二附属医院耳鼻喉科安徽合肥230601

目的探讨丹酚酸B(SalB)可能通过调控Lcn2改善非酒精性脂肪肝的作用。方法体内实验,8周龄♂C57BL/6J小鼠用普通维持饲料喂养,作为对照组,8周龄ApoE-/-小鼠用高脂饲料喂养,随机分为模型组和SalB组。在饲养8周后,SalB组小鼠用SalB灌胃,低... 详细信息

目的探讨丹酚酸B(SalB)可能通过调控Lcn2改善非酒精性脂肪肝的作用。方法体内实验,8周龄♂C57BL/6J小鼠用普通维持饲料喂养,作为对照组,8周龄ApoE-/-小鼠用高脂饲料喂养,随机分为模型组和SalB组。在饲养8周后,SalB组小鼠用SalB灌胃,低剂量为15 mg·kg^(-1)·d^(-1),高剂量为30 mg·kg^(-1)·d^(-1),对照组和模型组用等剂量生理盐水灌胃。肝脏转录组测序结果揭示模型组和SalB组的差异表达基因,HE染色、油红O染色观察肝组织的病理变化,试剂盒检测血清和肝组织的脂质、氧化应激和炎症指标,RT-qPCR检测Lcn2、SREBP-1C以及脂质合成相关酶的mRNA水平。体外实验,用棕榈酸(PA)诱导L02和LX-2细胞24 h建立NAFLD模型,用SalB(30μmol·L^(-1))和PA(0.2 mmol·L^(-1))共孵育检测SalB体外改善NAFLD的情况。试剂盒检测L02细胞TC、TG的含量,细胞油红O染色试剂盒检测L02细胞的脂质积累,RT-qPCR检测LX-2细胞Lcn2、SREBP-1C以及脂质合成相关酶基因的mRNA水平。结果模型组血清、肝脏的生化指标异常,肝组织脂质、炎症和氧化应激水平升高,出现大面积脂肪空泡和大量的脂质沉积,PA诱导的L02细胞也出现大量的脂质积累,在SalB干预后均有明显改善。转录组测序结果表明SalB可以调控肝脏脂质代谢和炎症。肝脏和LX-2细胞mRNA水平显示模型组Lcn2、SREBP-1C以及脂质合成相关酶基因表达明显上调,SalB干预后均能降低这些基因的表达。结论丹酚酸B可以明显改善非酒精性脂肪肝,其机制可能是通过下调Lcn2、SREBP-1C和脂质合成酶的表达。

关键词： SalB 非酒精性脂肪肝脂质代谢 Lcn2 SREBP-1C 脂质合成相关酶

民族地区高等教育资源赋能新质生产力发展——基于科技投入和产业集聚路径的检验

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南宁师范大学学报（自然科学版） 2025年第1期42卷 1-12页

作者：纪明吴家榕南宁师范大学经济与管理学院广西南宁530299

高等教育作为教育、科技和人才良性循环的汇聚点,构成了推动新质生产力发展的基石。基于2006—2022年民族地区45个地级市的面板数据,构建新质生产力和高等教育资源指标体系,实证检验二者之间的关系,并探讨科技投入和产业集聚在二者间的... 详细信息

高等教育作为教育、科技和人才良性循环的汇聚点,构成了推动新质生产力发展的基石。基于2006—2022年民族地区45个地级市的面板数据,构建新质生产力和高等教育资源指标体系,实证检验二者之间的关系,并探讨科技投入和产业集聚在二者间的调节和门槛效应。研究表明:高等教育资源能够显著促进新质生产力发展;科技投入和产业集聚在高等教育资源对新质生产力的影响中发挥了重要的调节作用;门槛效应检验结果显示,随着科技投入和产业集聚水平的提高,高等教育资源对新质生产力的促进作用更加明显;高等教育资源与新质生产力的关系存在空间异质性,高等教育资源在促进当地新质生产力发展的同时,也能实现区域间的正向溢出效应。

关键词：新质生产力高等教育资源科技投入产业集聚民族地区

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Precision Calculations of Atomic Polarizabilities： A Relevant Physical Quantity in Modern Atomic Frequency Standard

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Chinese Physics Letters 2010年第6期27卷 78-81页

作者： GAO Xiang LI jia-ming Department of Physics Shanghai Jiao Tong University Shanghai 200240 Department of Physics and Key Laboratory of Atomic and Molecular Nanosciences of Ministry of Education Tsinghua University Beijing 100084

Electric dipole polarizabilities of atoms are very important in many different physical applications, such as the precision atomic frequency standard. Calculations of these properties are very important and challenging. We propose a calculation strategy to calculate the frequency dependent dipole polarizabilities with high precision variationally by using a set of high quality orbital bases where the electron correlations can be taken into account adequately. The static polarizabilitiez of the ground state of Na are calculated accurately by such a method and can be compared with precision experiment measurement directly. The calculation result is in excellent agreement with the available experimental measurements within about 0.1~, which demonstrates the validity of our strategy. Our calculation strategy has a wide usage, not only in polarizibilies, but also in other fields such as theoretical treatment of electron-atom scattering processes. Using the same orbital bases, we carry out precision calculation of Na- affinities. Our calculated affinity is in excellent agreement with precision laser spectroscopy measurements within 0. 1%.

关键词： PHYSICAL constants ATOMIC frequency standards DIPOLE moments POLARIZABILITY (Electricity) VARIATIONAL principles ATOMIC orbitals SCATTERING (Physics) LASER spectroscopy

Crevice Corrosion Behaviors Between CFRP and Stainless Steel 316L for Automotive Applications

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Acta Metallurgica Sinica(English Letters) 2019年第10期32卷 1219-1226页

作者： Xia-Yu Wu jia-Kun Sun jia-ming Wang Yi-ming jiang Jin Li Department of Materials Science Fudan University

Carbon fiber reinforced plastics (CFRP) are promising lightweight materials for vehicle applications. 316L is one of the most widely used types of austenite stainless steels and applied in lots of automotive applications. The existence of crevices will result in galvanic corrosion and crevice corrosion when CFRPs and 316L are directly connected. A crevice former for the galvanic system was therefore designed and applied to evaluate the crevice corrosion behaviors and study the mechanism of galvanic crevice corrosion through several electrochemical techniques in this research. The results showed that the crevice corrosion of galvanic systems grew from crevice mouth to the inside crevice and could be divided into four steps, metastable pitting corrosion at the crevice mouth, initiating step of crevice corrosion, propagating step and ending step of crevice corrosion. Because of the influences of the galvanic system, electrode reaction rates were speeded up and the passivation region was shortened at the initiating stage of crevice corrosion. Corrosion rate was observed to be higher in the galvanic system than that in normal crevice systems.

关键词： Crevice corrosion Galvanic system Carbon fiber reinforced plastics 316L stainless steels

Research on the iterative method for model updating based on the frequency response function

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Acta Mechanica Sinica 2012年第2期28卷 450-457页

作者： Wei-ming Li jia-Zhen Hong Department of Engineering Mechanics Shanghai Jiaotong University200240 ShanghaiChina

Model reduction technique is usually employed in model updating process. In this paper, a new model updat- ing method named as cross-model cross-frequency response function （CMCF） method is proposed and a new iterative method associating the model updating method with the mo- del reduction technique is investigated. The new model up- dating method utilizes the frequency response function to avoid the modal analysis process and it does not need to pair or scale the measured and the analytical frequency re- sponse function, which could greatly increase the number of the equations and the updating parameters. Based on the traditional iterative method, a correction term related to the errors resulting from the replacement of the reduction ma- trix of the experimental model with that of the finite element model is added in the new iterative method. Comparisons be- tween the traditional iterative method and the proposed itera- tive method are shown by model updating examples of solar panels, and both of these two iterative methods combine the CMCF method and the succession-level approximate reduc- tion technique. Results show the effectiveness of the CMCF method and the proposed iterative method .

关键词： Model updating Model reduction Frequency response function Iteration