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Journal of Materials Science & Technology 2024年第1期168卷 157-168页

作者： Taoyu Zhou Jiuxu Yang Nan Li Hao Sun bohua zhang Zibo Zhao Qingjiang Wang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The fabrication of ultrafine-grained microstructures(grain size below 1μm)in titanium alloys is beneficial for improving their mechanical properties at room temperature and medium tempera-tures(400-550°C).However,a long-standing challenge involves the low-cost manufacturing of bulk ultrafine-grained titanium *** this work,we developed a facile strategy through martensite de-composition at thermal-mechanical coupling conditions,to fabricate an equiaxed microstructure in a Ti6Al4Mo4Zr1W0.2Si model alloy with an averageαgrain size of 315±62 *** formation of the ultrafine-grained microstructure was because the lattice strain stored in the martensitic initial mi-crostructure enhanced the nucleation rate of dynamic recrystallization,meanwhile,the pinning role of martensite decomposition productsβand(Ti,Zr)_(5)Si_(3)phases suppressed grain coarsening at high *** to conventional(α+β)alloys,the tensile strength of this alloy improved by 20%-30%at both room temperature and 550°C,without decreasing its *** situ SEM observations revealed that the ultrafine-grained microstructure would not only suppress dislocation motions but also contribute to the homogenous deformation in the matrix of the material,therefore,it resulted in higher mechanical *** research results may be of great significance to the development of next-generation aviation titanium alloys.

关键词： Ultrafine-grained Titanium alloy In situ observation Deformation mechanism Thermostability

攀西橄辉岩型低品位钛铁矿振动脉动与脉动高梯度磁选工艺对比

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中国有色金属学报 2024年第3期34卷 959-969页

作者：吴连军陈禄政吴宁熊涛张铂华曾剑武刘潇倩昆明理工大学国土资源工程学院昆明650093 攀钢集团研究院有限公司钒钛资源综合利用国家重点实验室攀枝花617000 赣州金环磁选科技装备股份有限公司江西省磁选装备重点实验室赣州341000

随开采深度的增加,攀西钛铁矿中易泥化、与钛铁矿磁性差异较小的橄辉岩型钛铁矿含量增多,降低了脉动高梯度磁选机的分选指标,使后续浮选过程中合格钛精矿的生产成本和难度增大。针对这一问题,本文开展振动脉动高梯度磁选与脉动高梯度磁... 详细信息

随开采深度的增加,攀西钛铁矿中易泥化、与钛铁矿磁性差异较小的橄辉岩型钛铁矿含量增多,降低了脉动高梯度磁选机的分选指标,使后续浮选过程中合格钛精矿的生产成本和难度增大。针对这一问题,本文开展振动脉动高梯度磁选与脉动高梯度磁选橄辉岩型低品位钛铁矿的对比试验研究。结果表明:在钛粗精矿的TiO_(2)品位为9.00%、−0.074 mm粒级产率为57.60%的条件下,采用SLon−100周期式脉动高梯度磁选机分选时,所得磁性精矿的TiO_(2)品位为15%~17%,分选精度上限较低;采用SLon-Z−100周期式振动脉动高梯度磁选机分选时,所得磁性精矿的TiO_(2)品位为20%~22%,分选精度上限明显提高。在相近的磁性精矿TiO_(2)品位(15%)或TiO_(2)回收率(73%)条件下,振动脉动高梯度磁选工艺的各项分选指标均明显优于脉动高梯度磁选工艺,表明磁介质振动动态捕获模式具有更高的捕获选择性。

关键词：橄辉岩型低品位钛铁矿振动脉动高梯度磁选脉动高梯度磁选对比试验

蒸汽爆破对瓦尼桑黄子实体多糖提取及降血糖功效影响

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食品研究与开发 2024年第7期45卷 150-157页

作者：范祺张博华王丽王崇队张明马超中华全国供销合作总社济南果品研究所山东济南250220

选取瓦尼桑黄(Sanghuangporus vaninii)子实体作为研究对象,研究蒸汽爆破技术对瓦尼桑黄多糖溶出率的影响。蒸汽爆破压力为0.8 MPa时,多糖溶出率为1.45%,蒸汽爆破维压时间为240 s时,多糖溶出率最大为1.68%。多糖中相对含量较多的单糖种... 详细信息

选取瓦尼桑黄(Sanghuangporus vaninii)子实体作为研究对象,研究蒸汽爆破技术对瓦尼桑黄多糖溶出率的影响。蒸汽爆破压力为0.8 MPa时,多糖溶出率为1.45%,蒸汽爆破维压时间为240 s时,多糖溶出率最大为1.68%。多糖中相对含量较多的单糖种类为岩藻糖、半乳糖、葡萄糖、木糖、甘露糖和葡糖醛酸且葡萄糖占比最高。蒸汽爆破处理后的瓦尼桑黄多糖与未蒸汽爆破处理的样品相比,对α-葡萄糖苷酶活性抑制作用更强,对斑马鱼有更高的安全剂量,可明显提升荧光标记脱氧葡萄糖类似物(2-NBD-glucose,2-NBDG)在斑马鱼体内的转运效率,表明蒸汽爆破处理后的样品降血糖功效更加明显。

关键词：蒸汽爆破瓦尼桑黄多糖斑马鱼降血糖

Nanodroplet-mediated catheter-directed sonothrombolysis of retracted blood clots

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Microsystems & Nanoengineering 2021年第1期7卷 77-83页

作者： Leela Goel Huaiyu Wu bohua zhang Jinwook Kim Paul A.Dayton Zhen Xu Xiaoning Jiang Department of Mechanical&Aerospace Engineering North Carolina State UniversityRaleighNC 27695USA The Joint Department of Biomedical Engineering The University of North Carolina at Chapel Hill and North Carolina State UniversityChapel HillNC 27599USA Department of Biomedical Engineering University of MichiganAnn ArborMI 48109USA

One major challenge in current microbubble(MB)and tissue plasminogen activator(tPA)-mediated sonothrombolysis techniques is effectively treating retracted blood clots,owing to the high density and low porosity of retracted ***(NDs)have the potential to enhance retracted clot lysis owing to their small size and ability to penetrate into retracted clots to enhance drug *** the first time,we demonstrate that a sub-megahertz,forwardviewing intravascular(FVI)transducer can be used for ND-mediated sonothrombolysis,in *** this study,we determined the minimum peak negative pressure to induce cavitation with low-boiling point phase change nanodroplets and clot *** then compared nanodroplet mediated sonothrombolysis to MB and tPA mediate *** clot lysis as a percent mass decrease in retracted clots was 9±8%,9±5%,16±5%,14±9%,17±9%,30±8%,and 40±9%for the control group,tPA alone,tPA+US,MB+US,MB+tPA+US,ND+US,and ND+tPA+US groups,*** retracted blood clots,combined ND-and tPA-mediated sonothrombolysis was able to significantly enhance retracted clot lysis compared with traditional MB and tPA-mediated sonothrombolysis *** nanodroplet with tPA-mediated sonothrombolysis may provide a feasible strategy for safely treating retracted clots.

关键词： thrombolysis directed boiling

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隧道工程课程“一体六翼”教学改革研究

创新创业理论研究与实践 2024年第5期7卷 30-33页

作者：鲍先凯崔广芹张博华田志超张童内蒙古科技大学土木工程学院内蒙古包头014010

随着我国经济快速发展,公路、铁路、城市地铁以及轨道交通工程的大规模建设将隧道工程发展推向新的高度。为满足现行工程行业背景下的人才需求,需培养学生成为创新应用型隧道专业技术人才,因此,对高校隧道工程课程教学提出更新、更高的... 详细信息

随着我国经济快速发展,公路、铁路、城市地铁以及轨道交通工程的大规模建设将隧道工程发展推向新的高度。为满足现行工程行业背景下的人才需求,需培养学生成为创新应用型隧道专业技术人才,因此,对高校隧道工程课程教学提出更新、更高的要求。该文提出“一体六翼”隧道工程课程教学模式,以培养学生成为创新应用型人才为主体目标,通过教学内容模块化,理论教学可视化,施工事故案例化,教学内容、大纲、讲义、教案与时俱进化,教学方法多样化,教学手段、培养方式先进化6个方面围绕“一体”共同发展,从而提升教学效果,提高人才培养质量。

关键词：隧道工程高校教育教学改革 “一体六翼” 应用型人才培养

不同处理方式对牛蒡根多糖提取率及抗氧化活性的影响

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中国果菜 2024年第6期44卷 11-15页

作者：王崇队张明王丽范祺张博华胡付侠马超中华全国供销合作总社济南果品研究所山东济南250014

为了研究不同处理方式对牛蒡根理化性质及抗氧化活性的影响,为牛蒡根多糖提取、产品开发提供新思路,本研究以超微粉碎、蒸汽爆破和双螺杆挤压熟化处理牛蒡根后,提取牛蒡根多糖,测定牛蒡根多糖提取液的抗氧化活性。结果表明,超微粉碎处... 详细信息

为了研究不同处理方式对牛蒡根理化性质及抗氧化活性的影响,为牛蒡根多糖提取、产品开发提供新思路,本研究以超微粉碎、蒸汽爆破和双螺杆挤压熟化处理牛蒡根后,提取牛蒡根多糖,测定牛蒡根多糖提取液的抗氧化活性。结果表明,超微粉碎处理后牛蒡根多糖提取率最高,为36.03%。蒸汽爆破处理后牛蒡根多糖提取液DPPH自由基清除能力和羟基自由基清除能力最强,其中较未处理的牛蒡根提多糖取液DPPH自由基清除能力提高15.96%。螺杆挤压熟化处理后牛蒡根多糖提取液还原力最强,较未处理的牛蒡根多糖提取液提高15.60%。蒸汽爆破处理后菊糖的提取率最高,为34.94%。

关键词：牛蒡根超微粉碎蒸汽爆破螺杆挤压多糖提取率抗氧化性

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{332}<113> Twinning transfer behavior and its effect on the twin shape in a beta-type Ti-23.1Nb-2.0Zr-1.0O alloy

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Journal of Materials Science & Technology 2021年第32期91卷 58-66页

作者： Yi Yang bohua zhang Zhichao Meng Lei Qu Hao Wang Sheng Cao Jianan Hu Hao Chen Songquan Wu Dehai Ping Geping Li Lai-Chang zhang Rui Yang Aijun Huang School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Northwest Institute for Non-ferrous Metal Research Xi’an 710016China School of Materials University of ManchesterOxford RoadManchester M139PLUnited Kingdom National Institute for Materials Science Sengen 1-2-1Tsukuba 305-0047Japan School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia Department of Materials Science and Engineering Monash UniversityClaytonVIC 3800Australia

The interaction between twins and grain boundaries(GB) has an important influence on the deformation and fracture behavior of materials. In the present work, {332} twinning transfer(TT) behavior and its effect on the twin shape in a deformed β-type Ti-23.1 Nb-2.0 Zr-1.0 O Ti alloy were investigated experimentally and with molecular dynamics simulation. The crystallographic alignment factor of the two twinning systems in the neighboring grains and the misorientation angle of the grain pairs were found to influence the occurrence of TT. This further determines the twin shape: twins present a ruler shape when TT occurs but are in a lenticular shape otherwise. Such different twin shapes are attributed to the local stress states related to TT occurring or not. Both ruler-shaped paired twinning and lenticular twinning would provide effective mechanisms to release or reduce the stress concentration in front of the twin tips in different grain pairs.

关键词： Titanium alloys Plastic deformation Grain boundaries Twinning Twin shape

Extraction of fractures in shale CT images using improved U-Net

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Energy Geoscience

Energy Geoscience 2024年第2期5卷 240-248页

作者： Xiang Wu Fei Wang Xiaoqiu zhang bohua Han Qianru Liu Yonghao zhang College of Geology Engineering and Geomatics Chang'an UniversityXi'anShaanxi710054China Qinghai Oilfield Exploration and Development Research Institute DunhuangGansu736202China China Petroleum Logging Co.Ltd. Xi'anShaanxi710077China

Accurate extraction of pores and fractures is a prerequisite for constructing digital rocks for physical property simulation and microstructural response ***,fractures in CT images are similar in grayscale to the rock matrix,and traditional algorithms have difficulty to achieve accurate segmentation *** this study,a dataset containing multiscale fracture information was constructed,and a U-Net semantic segmentation model with a scSE attention mechanism was used to classify shale CT images at the pixel level and compare the results with traditional *** results showed that the CLAHE algorithm effectively removed noise and enhanced the fracture information in the dark parts,which is beneficial for further fracture *** Canny edge detection algorithm had significant false positives and failed to recognize the internal information of the *** Otsu algorithm only extracted fractures with a significant difference from the background and was not sensitive enough for fine *** MEF algorithm enhanced the edge information of the fractures and was also sensitive to fine fractures,but it overestimated the aperture of the *** U-Net was able to identify almost all fractures with good continuity,with an MIou and Recall of 0.80 and 0.82,*** the image resolution increases,more fine fracture information can be extracted.

关键词： CT slices Fracture segmentation Shale U-Net Deep learning

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不同干燥方式对灵芝子实体干燥品质的影响

中国果菜 2024年第3期44卷 43-47页

作者：张明孟晓峰吴茂玉和法涛范祺张博华王崇队马超中华全国供销合作总社济南果品研究所山东济南250014

采用热风干燥、热泵干燥、微波热泵耦合干燥、热泵梯度升温干燥、热泵梯度降温干燥等干燥方式,探究不同干燥方式对灵芝子实体感官、营养及理化品质的影响。结果表明,微波12 min+60℃热泵干燥脱水效率最高,较单一热风干燥至少缩短180 min... 详细信息

采用热风干燥、热泵干燥、微波热泵耦合干燥、热泵梯度升温干燥、热泵梯度降温干燥等干燥方式,探究不同干燥方式对灵芝子实体感官、营养及理化品质的影响。结果表明,微波12 min+60℃热泵干燥脱水效率最高,较单一热风干燥至少缩短180 min;微波4 min+60℃热泵干燥色泽保持相对较好;微波12 min+60℃热泵干燥粗多糖含量最高,较60℃热风干燥提高了63.26%;热泵梯度降温干燥对DPPH自由基的清除能力最强;60℃热泵干燥水溶性指数最高。从提高生产效率和营养成分保留率角度考虑,优先选择微波12 min+60℃热泵干燥方式;从产品良好色泽角度考虑,优先选择微波4 min+60℃热泵干燥方式;从产品良好功能活性角度考虑,优先选择热泵梯度降温干燥、60℃热泵干燥方式,为灵芝子实体干燥方式的选择提供理论依据。

关键词：灵芝子实体干燥品质微波干燥热泵干燥

Unlocking single-atom catalysts via amorphous substrates

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Nano Research 2024年第5期17卷 3533-3546页

作者： bohua Sun Mingyuan Xu Xiaoxia Li Baohong zhang Rui Hao Xiaoyu Fan Binbin Jia Dingshun She School of Engineering and Technology China University of Geosciences(Beijing)Beijing 100083China Zhengzhou Institute China University of Geosciences(Beijing)Zhengzhou 451283China College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China School of Chemistry Beihang UniversityBeijing 100191China Chinese Academy of Sciences(CAS)Key Laboratory of Nanosystem and Hierarchy Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China National Engineering Research Center of Nonferrous Metals Materials and Products for New EnergyChina GRINM Group Co.Ltd.Beijing 100088China

Single-atom catalysts(SACs)reveal great potential for application in catalysis due to their fully exposed active *** general,single atoms(SAs)and the coordination substrates need to have strong interactions or charge transfer to ensure the atomic dispersion,which requires the selection of a suitable substrate to stabilize the target *** studies have demonstrated that amorphous materials with abundant defects and coordinatively unsaturated sites can be used as substrates for more efficient capturing SAs,further enhancing the catalytic *** this review,we discuss recent research progress of SAs loaded on amorphous substrates for enhanced catalytic ***,we summarize the commonly used amorphous substrates for stabilizing ***,we present several advanced applications of amorphous SACs in the field of catalysis,including electrocatalysis and *** then,we also clarify the synergistic mechanism between SAs and amorphous substrate on catalytic ***,we summarize the challenges with our personal views and provide a critical outlook on how amorphous SACs continue to evolve.

关键词： single-atoms amorphous substrate synthetic strategy catalysis