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The centrosymmetric to non-centrosymmetric transformation induced by alkaline-earth cations producing infrared nonlinear optical AeMnGaS（Ae = Ca, Sr）

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Science China Chemistry 2024年

作者： Yang-Ping Zhang Shao-Min Pei Wen-Fa Chen Bin-Wen Liu Xiao-ming jiang Guo-Cong Guo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Physical Science and Technology Shanghai Tech University Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China

Non-centrosymmetric （NCS） structure is an indispensable prerequisite for second-order nonlinear optical （NLO） ***,the mainstream approach for designing new NCS structures still relies on chemical substitution,necessitating an urgent infusion of fresh *** this work,two isomorphic sulfides AeMn6Ga6S16（Ae=Ca,1;Sr,2） are afforded by modifying the skeleton of centrosymmetric （CS） Mn2Ga2S5via introducing strong electropositive alkaline-earth ***,the incorporation of Ca2+/Sr2+cations allows the elementary[MnGaS9]∞chains to reconfigure into bumpy[MnS6]-[GaS4]layers in a new engagement manner,thus enabling the conversion from CS to NCS *** modifications cause not only strong second-harmonic generation （SHG） responses （～1.5×benchmark AgGaS2@1,700 nm）,but also significantly feasible bandgaps（2.60–2.64 e V） compared to the sulfide Mn2Ga2S5（1.36 eV）,which ultimately facilitate ultrahigh laser-induced damage thresholds （4.4–6.6×AgGaS2@1,064 nm for compounds 1 and 2）.The present study offers an ingenious approach for the transformation of CS to NCS structure.

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用于高功率微波器件粒子模拟的三维柱坐标系共形网格生成技术

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强激光与粒子束 2024年第4期36卷 180-186页

作者：张磊翁明王玥蒋铭西安交通大学电子科学与工程学院电子物理与器件教育部重点实验室西安710049

基于面向对象的C++语言研制三维柱坐标共形网格生成程序,对束-场互作用器件作共形网格剖分,为粒子模拟算法提供积分线元、面元。通过定义三维柱坐标网格体系如网格步长、网格索引、守护网格层、包围盒等数据,使模型的空间信息能转换成... 详细信息

基于面向对象的C++语言研制三维柱坐标共形网格生成程序,对束-场互作用器件作共形网格剖分,为粒子模拟算法提供积分线元、面元。通过定义三维柱坐标网格体系如网格步长、网格索引、守护网格层、包围盒等数据,使模型的空间信息能转换成柱坐标网格信息。将轴上网格单元作特殊处理,使粒子模拟算法形式在轴上网格和在非轴上网格上保持一致。利用射线跟踪法得到属于模型子面、模型棱边的离散边界点,接着通过拓扑关系获得模型的顶点,保存上述三类离散边界点的拓扑信息和网格信息。将构建的基础网格元与边界点信息耦合,在离散网格体系中重构模型。用该共形网格剖分技术对相对论磁控管进行剖分,能够识别该磁控管的透明阴极、阳极和谐振腔等结构。

关键词：粒子模拟三维柱坐标网格剖分射线跟踪共形技术

Prophylactic effects of Edible Lilium-Egg yolk compound powder on depression-like behaviors in rats exposed to chronic unpredictable mild stress: A role of gut-brain axis

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Food Science and Human Wellness 2024年

作者： Yu Huang Yu-xin Luo Sai-nan Tian Meng-zhou Xie Liang Li ming-xing jiang Zhi-ying Yuan Hunan University of Chinese Medicine Key Laboratory of TCM Heart and Lung Syndrome Differentiation & Medicated Diet and Dietotherapy， Hunan University of Chinese Medicine TCM and Ethnomedicine Innovation & Development International Laboratory， School of Pharmacy， Hunan University of Chinese Medicine

The incidence rate and harmfulness of depression are increasing yearly， and the research on the antidepressant effect of regulating the intestinal microecology balance has attracted widespread attention. The purpose of this research was to study the preventive effects and the regulatory mechanism of edible Lilium-egg yolk compound powder(Chinese abbreviation， BHT) on gut-brain crosstalk in depressive rats induced by chronic unpredictable mild stress(CUMS) through the "microbiota-gut-brain" axis. Results showed that infusion of BHT for 21 days ameliorated the morphology of the hippocampus and colon， increased the rate of sucrose preference， reduced the immobility time of forced swimming， increased the expression level of anti-inflammatory cytokine Interleukin-10 (IL-10) in serum， up-regulate the expression level of plasma neurotransmitter 5-hydroxy tryptamine (5-HT)， down-regulate the expression of inflammatory factors tumor necrosis factor-α (TNF-α)， interleukin-6 (IL-6)， and interleukin-1β (IL-1β) and neurotransmitter glutamic acid (Glu) in serum， and decrease the expression levels of lipopolysaccharide (LPS)， diamine oxidase (DAO) and lactate dehydrogenase (LD) in plasma. The underlying mechanism may be to reduce the activation of microglia (lower levels of CD11b， IBa1 protein and gene expression)， regulate hippocampal GR/BDNF/NPY signal pathway (higher levels of GR， BDNF， NPY protein and gene expression)， enhance intestinal mucosal barrier function (higher levels of ZO-1， Occludin protein and gene expression)， regulate the composition and structure of intestinal flora(Analysis results of LEfSe combined with random forest showed that Prevotella and Paraprevotella might be biomarkers of BHT intervention in depression)， and it is related to the improvement of glutathione metabolism， and other metabolic pathways. Pearson correlation analysis found that 5-HT is strongly positively correlated with Prevotella，and Glu has a strong negative correlation with ***

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关系性生产:师范生实践性知识发展的第三空间路径

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黑龙江高教研究 2024年第2期42卷 124-129页

作者：屠明将重庆师范大学重庆400700

在构建新师范教育体系背景下,亟须以实践取向引领师范生培养模式整体变革。为扭转既有研究“虚无化”“经验化”“理论化”的缺陷,秉持新马克思主义者列斐伏尔的空间哲学理论,用社会关系再生产机制的第三空间路径解读师范生实践性知识... 详细信息

在构建新师范教育体系背景下,亟须以实践取向引领师范生培养模式整体变革。为扭转既有研究“虚无化”“经验化”“理论化”的缺陷,秉持新马克思主义者列斐伏尔的空间哲学理论,用社会关系再生产机制的第三空间路径解读师范生实践性知识生产过程,表现为交互主体性在一体化时空场域通过对话交往的关系行动,是师范生个体与他者交互调适以寻求“个体我”与“社会我”协调统一的社会化程序。怎样系统推动关系性生产的第三空间路径优化,需要从明确实践理性导向融合师范性与学术性争议、强调实践素养贯穿师范生培养质量标准、突显时空一体建构校地协同机制、重视课堂中心的课程教学联动变革以及营造关系循环互动的知识生产文化等方面推动师范教育培养范式转型。

关键词：关系性生产实践性知识第三空间路径

Biomimetic natural biomaterials for tissue engineering and regenerative medicine:new biosynthesis methods,recent advances,and emerging applications

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Military Medical Research 2024年第1期11卷 50-79页

作者： Shuai Liu jiang-ming Yu Yan-Chang Gan Xiao-Zhong Qiu Zhe-Chen Gao Huan Wang Shi-Xuan Chen Yuan Xiong Guo-Hui Liu Si-En Lin Alec McCarthy Johnson V.John Dai-Xu Wei Hong-Hao Hou Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering the Fifth Affiliated HospitalSchool of Basic Medical ScienceSouthern Medical UniversityGuangzhou 510900China Department of Orthopedics Tongren HospitalShanghai Jiao Tong UniversityShanghai 200336China The Eighth Affiliated Hospital Sun Yat-Sen UniversityShenzhen 518033GuangdongChina Engineering Research Center of Clinical Functional Materials and Diagnosis&Treatment Devices of Zhejiang Province Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhou 325011ZhejiangChina Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Orthopaedics and Traumatology Faculty of Medicinethe Chinese University of Hong KongHong Kong SAR 999077China Department of Functional Materials Terasaki Institute for Biomedical InnovationLos AngelesCA 90064USA Mary&Dick Holland Regenerative Medicine Program College of MedicineUniversity of Nebraska Medical CenterOmahaNE 68130USA Zigong Affiliated Hospital of Southwest Medical University Zigong Psychiatric Research CenterZigong Institute of Brain ScienceZigong 643002SichuanChina Key Laboratory of Resource Biology and Biotechnology in Western China Ministry of EducationSchool of MedicineDepartment of Life Sciences and MedicineNorthwest UniversityXi’an 710127China

Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative *** contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECM).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative *** paper provides an overview for recent progress of biomimetic natural biomaterials(BNBMs),including advances in their preparation,functionality,potential applications and future *** highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ***,we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE ***,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field.

关键词： Biomimic Scaffold Biosynthesis Natural biomaterial Tissue engineering

Evolution of helium bubbles in FeCoNiCr-based high-entropy alloys containing γ′ nanoprecipitates

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Chinese Physics B 2024年第7期33卷 491-500页

作者：冯婷蒋胜明胡潇天张子骏黄子敬董士刚张建 College of Energy Xiamen UniversityXiamen 361005China16

A series of high-entropy alloys(HEAs) containing nanoprecipitates of varying sizes is successfully prepared by a non-consuming vacuum arc melting *** order to study the irradiation evolution of helium bubbles in the FeCoNiCrbased HE As with γ' precipitates,these samples are irradiated by 100-keV helium ions with a fluence of 5 × 10^(20) ions/m^(2) at 293 K and 673 K,*** the samples irradiated at room temperature are annealed at different temperatures to examine the diffusion behavior of helium *** electron microscope(TEM) is employed to characterize the structural morphology of precipitated nanoparticles and the evolution of helium *** results reveal that nanosized,spherical,dispersed,coherent,and ordered L1_(2)-type Ni_(3)Ti γ' precipitations are introduced into FeCoNiCr(Ni_(3)Ti)_(0.1) HEAs by means of ageing treatments at temperatures between 1073 K and 1123 *** the ageing treatment conditions adopted in this work,γ' nanoparticles are precipitated in FeCoNiCr(Ni_(3)Ti)_(0.1) HE As,with average diameters of 15.80 nm,37.09 nm,and 62.50 nm,*** average sizes of helium bubbles observed in samples after 673-K irradiation are 1.46 nm,1.65 nm,and 1.58 nm,*** improvement in the irradiation resistance of FeCoNiCr(Ni_(3)Ti)_(0.1) HEAs is evidenced by the diminution in bubbles ***,the FeCoNiCr(Ni_(3)Ti)_(0.1) HEAs containing γ' precipitates of 15.8 nm exhibits the minimum size and density of helium bubbles,which can be ascribed to the considerable helium trapping effects of heterogeneous coherent phase ***,annealing experiments conducted after 293-K irradiation indicate that HEAs containing precipitated phases exhibits smaller apparent activation energy(E_(a)) for helium bubbles,resulting in larger helium bubble *** study provides guidance for improving the irradiation resistance of L1_(2)-strengthened high-entropy alloy.

关键词： high-entropy alloys irradiation resistance coherent precipitates helium bubbles

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Properties of radiation defects and threshold energy of displacement in zirconium hydride obtained by new deep-learning potential

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Chinese Physics B 2024年第7期33卷 456-465页

作者：王玺唐孟蒋明璇陈阳春刘智骁邓辉球 School of Physics and Electronics Hunan UniversityChangsha 410082China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

Zirconium hydride(ZrH_(2)) is an ideal neutron moderator material. However, radiation effect significantly changes its properties, which affect its behavior and the lifespan of the reactor. The threshold energy of displacement is an important quantity of the number of radiation defects produced, which helps us to predict the evolution of radiation defects in ZrH_(2).Molecular dynamics(MD) and ab initio molecular dynamics(AIMD) are two main methods of calculating the threshold energy of displacement. The MD simulations with empirical potentials often cannot accurately depict the transitional states that lattice atoms must surpass to reach an interstitial state. Additionally, the AIMD method is unable to perform largescale calculation, which poses a computational challenge beyond the simulation range of density functional theory. Machine learning potentials are renowned for their high accuracy and efficiency, making them an increasingly preferred choice for molecular dynamics simulations. In this work, we develop an accurate potential energy model for the ZrH_(2) system by using the deep-potential(DP) method. The DP model has a high degree of agreement with first-principles calculations for the typical defect energy and mechanical properties of the ZrH_(2) system, including the basic bulk properties, formation energy of point defects, as well as diffusion behavior of hydrogen and zirconium. By integrating the DP model with Ziegler–Biersack–Littmark(ZBL) potential, we can predict the threshold energy of displacement of zirconium and hydrogen in ε-ZrH_(2).

关键词： zirconium hydride deep learning potential radiation defects molecular dynamics threshold energy of displacement

泸定M_(S)6.8级地震大岗山拱坝横缝及阻尼器工作性态分析

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岩土力学 2024年第5期45卷 1527-1539页

作者：江德军黄会宝巨淑君高强蒋明成国能大渡河流域水电开发有限公司四川成都610041 四川大学水利水电学院四川成都610065 成都理工大学地质灾害防治与地质环境保护国家重点实验室四川成都610059

横缝作为高拱坝强度的薄弱部位,在地震作用下的工作性态至关重要。泸定M_(S)6.8级(面波震级)地震中,大岗山拱坝坝顶顺河向峰值加速度PGA达到586.63 cm/s^(2),坝址烈度达Ⅷ度,是唯一经历近场强震考验及设置阻尼器抗震措施的200m级高拱坝... 详细信息

横缝作为高拱坝强度的薄弱部位,在地震作用下的工作性态至关重要。泸定M_(S)6.8级(面波震级)地震中,大岗山拱坝坝顶顺河向峰值加速度PGA达到586.63 cm/s^(2),坝址烈度达Ⅷ度,是唯一经历近场强震考验及设置阻尼器抗震措施的200m级高拱坝。依据震后大坝横缝及阻尼器宏观现象和监测原观数据,对横缝及阻尼器工作性态进行了分析,结果表明地震过程中大坝横缝存在开合过程,震后部分横缝存在残余张开,开度增量在-0.05~0.43mm之间,总体表现为下游侧略大于上游侧,左岸大于右岸,初步分析主要由于横缝高频开合导致灌浆材料部分剥离测缝计无法复位,拱坝仍处于弹性工作状态;拱坝坝顶3组阻尼器在地震前后两端位移增量在0.32~1.06 mm之间,表现为拉伸,其中靠近拱冠梁的16#横缝位移增量最大。结合测缝计监测成果初步分析,阻尼器在强震作用下对降低局部区域横缝开度有一定作用,在主震后的历次余震中阻尼器未见明显动作痕迹。相关成果可为震后大坝安全评估、高拱坝抗震设计及研究提供参考。

关键词：泸定地震大岗山拱坝横缝阻尼器

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基于图像处理的轮胎X光图像缺陷检测

轮胎工业 2024年第4期44卷 250-255页

作者：姜明青岛科技大学信息科学技术学院山东青岛266061

在图像处理的基础上使用深度学习方法对轮胎X光图像缺陷进行自动检测。轮胎X光图像具有高分辨率、形状狭长、缺陷目标较小的特点,通过将每张X光图像按照640×640像素进行切割,对切割出的每个区域进行标注,把存在缺陷的区域划分到训练集... 详细信息

在图像处理的基础上使用深度学习方法对轮胎X光图像缺陷进行自动检测。轮胎X光图像具有高分辨率、形状狭长、缺陷目标较小的特点,通过将每张X光图像按照640×640像素进行切割,对切割出的每个区域进行标注,把存在缺陷的区域划分到训练集,对训练集进行直方图均衡化以增强图像前景与背景的对比度,进而继续对训练集进行数据增强以提高模型的泛化能力,最后在Faster R-CNN深度学习缺陷检测模型上训练出最优权重。在模型推理阶段,完整的X光图像会被送入模型,缺陷范围被框出,重组为原始X光图像;若某个缺陷具有多个选框,则将所有邻近的选框合成为一个选框。该方法能够有效降低小缺陷目标的漏检率,提高检测的准确率,间接解决了原始X光图像特征丢失的问题。

关键词：轮胎X光图像图像处理深度学习缺陷检测