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Journal of Materials Science & Technology 2016年第4期32卷 320-325页

作者： Zhi Liu kan song Bo Gao Tian Tian Haiou Yang Xin Lin Weidong Huang State Key Laboratory of Military Stomatology Department of Prosthodontics School of Stomatology Fourth Military Medical University State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Directionally solidified eutectic ceramics such as Al2O3/ZrO2 are promising structural materials for ap- plications in harsh environment with an ultrahigh temperature. In this work, through adopting assistant heating laser 3D printing, Al2O3/ZrO2 eutectic samples were manufactured with suppressing the forma- tion of cracks. The dependence of the average rod spacing （λav） on the scanning rate （V） follows a relation with λavV0.5 = 1 μm1.5 s^-0.5. Typical eutectic microstructures, so-called complex regular, were analyzed with respect to its evolution with modulating the growth conditions. Formation mechanism of the solidifi- cation defect, shrinkage porosity, was discussed and the defect is found to be significantly suppressed by optimizing the solidification parameters. The maximum hardness and fracture toughness are mea- sured to he 16.7 GPa and 4.5 MPa m1/2, respectively. The interplay between the propagation of cracks and the Al2O3/ZrO2 interface is discussed.

关键词： Al2O3 ZrO2 Eutectic Solidification

Comparative evaluation of commercial Douchi by different molds:biogenic amines,non-volatile and volatile compounds

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Food Science and Human Wellness 2024年第1期13卷 434-443页

作者： Aijun Li Gang Yang Zhirong Wang Shenglan Liao Muying Du Jun song Jianquan kan College of Food Science Southwest UniversityChongqing 400715China Chinese-Hungarian Cooperative Research Centre for Food Science Chongqing 400715China Laboratory of Quality&Safety Risk Assessment for Agri-products on Storage and Preservation(Chongqing) Ministry of Agriculture and Rural Affairs of the People's Republic of ChinaChongqing 400715China Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing Chongqing 400715China Shu Xiang Douchi Food Research Institute Limited Company Chongqing 402160China

To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fermentation of Douchi.The results showed that the biogenic amine contents of the three types of Douchi were all within the safe range and far lower than those of traditional fermented Douchi.Aspergillus-type Douchi produced more free amino acids than the other two types of Douchi,and its umami taste was more prominent in sensory evaluation(P<0.01),while Mucor-type and Rhizopus-type Douchi produced more esters and pyrazines,making the aroma,sauce,and Douchi flavor more abundant.According to the Pearson and PLS analyses results,sweetness was significantly negatively correlated with phenylalanine,cysteine,and acetic acid(P<0.05),bitterness was significantly negatively correlated with malic acid(P<0.05),the sour taste was significantly positively correlated with citric acid and most free amino acids(P<0.05),while astringency was significantly negatively correlated with glucose(P<0.001).Thirteen volatile compounds such as furfuryl alcohol,phenethyl alcohol,and benzaldehyde caused the flavor difference of three types of Douchi.This study provides theoretical basis for the selection of starting strains for commercial Douchi production.

关键词： Douchi Starting strains Non-volatile compounds Volatile compounds Sensory evaluation

Mechanical behaviours of bedded sandstone under hydromechanical coupling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1245-1261页

作者： Junwen Zhang Zhixiang song Lichao Zhang Shaokang Wu Shanyong Wang Yang Zhang Xukai Dong Jinxin Wang Yanbo Han Baohua kan School of Energy and Mining Engineering China University of Mining and Technology (Beijing)Beijing100083China Jarud Banner Zhahanao'er Coal Industry Co. Ltd.ZhaluteqiInner Mongolia029200China Priority Research Centre for Geotechnical Science & Engineering The University of NewcastleCallaghanNSW 2308Australia

The combination of the dipping effect and hydromechanical(H-M)coupling effect can easily lead to water inrush disasters in water-rich roadways with different dip angles in coal mines.Therefore,H-M coupling tests of bedded sandstones under identical osmotic pressure and various confining pressures were conducted.Then,the evolution curves of stress-strain,permeability and damage,macro-and mesoscopic failure characteristics were obtained.Subsequently,the mechanical behaviour was characterized,and finally the failure mechanism was revealed.The results showed that:(1)The failure of the sandstone with the bedding angle of 45°or 60°was the structure-dominant type,while that with the bedding angle of 0°,30°or 90°was the force-dominant type.(2)When the bedding angle was in the range of(0°,30°)or(45°,90°),the confining pressure played a dominant role in influencing the peak strength.However,withinβ∈(30°,45°),the bedding effect played a dominant role in the peak strength.(3)With the increase in bedding angle,the cohesion increased first,then decreased and finally increased,while the internal friction angle was the opposite.(4)When the bedding angle was 0°or 30°,the“water wedging”effect and the“bedding buckling”effect would lead to the forking or converging shear failure.When the bedding angle was 45°or 60°,the sliding friction effect would lead to the shear slipping failure.When the bedding angle was 90°,the combination of the“bedding buckling”effect and shear effect would lead to the mixed tension-shear failure.The above conclusions obtained are helpful for the prevention of water inrush disasters in water-rich roadways with different dips in coal mines.

关键词： Hydromechanical coupling Bedded sandstones Mechanical behaviour Bedding effect Failure mechanism

Comparative genomic analysis of Lactobacillus crispatus strains Lc31 and Lc83 with anti-cervical cancer potential by complete genome sequencing

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Cancer Advances 2023年第18期6卷 1-14页

作者： Xue-Qin Cai Ruo-Nan Li Yan Ma Xi-xi Chen Li-Juan Wan Jin-song kan Hui-Yan Wang Department of Laboratory Diagnostics the First Affliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Obstetrics and Gynecology the First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Gynecologic Oncology the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China

Lactobacillus crispatus is a commonly found species in the urogenital tract(UGT)of healthy females and can also colonize other niches,such as the gastrointestinal tract(GIT).Although its potential protective role in cervical cancer has been reported,the anticancer mechanisms involved are still unclear.In this study,we sequenced and characterized the complete genomes of two L.crispatus strains(Lc31 and Lc83)isolated from the UGT of healthy women of reproductive age.Phylogenetic and phylogenomic analyses of these two strains and 15 other L.crispatus strains with complete genome sequences revealed that strains from the UGT and GIT clustered separately.UGT strains had a larger genome size,higher GC contents,and more protein-coding sequences and insertion sequence(Is)elements,indicating the likelihood of active horizontal gene transfer in this niche.We found a universal presence of genes encoding bacteriocins and the absence of virulence factors and antibiotic resistance genes in UGT strains,suggesting the potential of L.crispatus as a urogenital probiotic.Comparative genomic analysis identified an ula gene cluster responsible for L-ascorbate catabolism exclusively in UGT strains,and carbohydrate fermentation experiments confirmed that this substrate supported the growth of L.crispatus Lc31 and Lc83.Our findings improve the understanding of how the genome determines niche adaptation by L.crispatus,providing a foundation for investigating the mechanisms by which urogenital-derived L.crispatus promotes female health.

关键词： Lactobacillus crispatus anti-cervical cancer genetic diversity comparative genomics antibiotic susceptibility L-ascorbate catabolism

供应链视角下航空运输企业采购成本管控体系初探

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全国流通经济 2022年第2期 49-51页

作者：宋侃中国国际航空股份有限公司西南分公司四川成都610200

新冠疫情暴发以来,民航遭受史无前例的重创,航空运输行业持续亏损,效益攻坚成为航空运输企业的关键工作。在国内外市场普遍受挫、高铁网络瓜分市场的大背景下,革新运营理念、加强成本管控、优化成本结构,成为后疫情时代航企生存运营的... 详细信息

新冠疫情暴发以来,民航遭受史无前例的重创,航空运输行业持续亏损,效益攻坚成为航空运输企业的关键工作。在国内外市场普遍受挫、高铁网络瓜分市场的大背景下,革新运营理念、加强成本管控、优化成本结构,成为后疫情时代航企生存运营的重要影响因素。本文基于现代供应链管理理念,从供应链上游的采购活动出发,对航空运输企业采购活动及管理现状进行分析,并就构建采购成本管控体系提出几点思考。

关键词：供应链航空运输企业采购成本管控

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我国房建施工企业原始创新分析

工程质量 2022年第9期40卷 81-84页

作者：宋衎吴娇中建三局第一建设工程有限责任公司湖北武汉430040 江西财经大学产业经济研究院江西南昌330013

原始创新是施工企业持续创新和可持续发展的关键动力。论文通过选取15家代表性施工企业,以发明专利申请和授权情况为切入点进行分析,发现总体上房建施工企业的原始创新申请意愿和能力稍弱于路桥等行业,但近5年房建施工企业的发明专利增... 详细信息

原始创新是施工企业持续创新和可持续发展的关键动力。论文通过选取15家代表性施工企业,以发明专利申请和授权情况为切入点进行分析,发现总体上房建施工企业的原始创新申请意愿和能力稍弱于路桥等行业,但近5年房建施工企业的发明专利增长较快。以中建三局为例,从专利结构、技术类型、主要发明人、技术前沿关注情况来深度分析,发现企业原始创新能力在不断增强,且对前沿技术的关注和创新已取得一定成果。

关键词：施工企业原始创新发明专利现状

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碳纤维改性PTFE密封材料制备技术研究

化工新型材料 2013年第4期41卷 81-83页

作者：周波阚松徐州工业职业技术学院徐州221140 南车南京浦镇车辆有限公司南京210031

以碳纤维为增强材料,采用冷压成型和自由烧结工艺制备改性聚四氟乙烯(PTFE)密封复合材料。通过制备工艺的实验研究,详细分析了混料工艺,得出:最佳的添料次数为4次,搅拌时间约10min;碳纤维粉对复合材料的抗拉强度有削弱作用,短碳纤维提... 详细信息

以碳纤维为增强材料,采用冷压成型和自由烧结工艺制备改性聚四氟乙烯(PTFE)密封复合材料。通过制备工艺的实验研究,详细分析了混料工艺,得出:最佳的添料次数为4次,搅拌时间约10min;碳纤维粉对复合材料的抗拉强度有削弱作用,短碳纤维提高复合材料的抗拉强度;等离子表面处理法对复合材料的抗拉强度提高最好。

关键词：聚四氟乙烯纤维密封材料制备技术

氯沙坦对脓毒症小鼠急性肾损伤的影响及其与线粒体融合-分裂的关系

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中华麻醉学杂志 2024年第2期44卷 220-224页

作者：王恩全阚宇飞孟姝岐宋宇谢克亮天津医科大学总医院麻醉科、天津市麻醉学研究所天津300052 天津医科大学总医院重症医学科天津300052

目的评价氯沙坦对脓毒症小鼠急性肾损伤的影响及其与线粒体融合-分裂的关系。方法 SPF级雄性C57BL/6J小鼠128只,6~8周龄,体质量20~25 g,采用随机数字表法分为4组(n=32):假手术组(Sham组)、假手术+氯沙坦组(Sham+LOS组)、脓毒症相关性急... 详细信息

目的评价氯沙坦对脓毒症小鼠急性肾损伤的影响及其与线粒体融合-分裂的关系。方法 SPF级雄性C57BL/6J小鼠128只,6~8周龄,体质量20~25 g,采用随机数字表法分为4组(n=32):假手术组(Sham组)、假手术+氯沙坦组(Sham+LOS组)、脓毒症相关性急性肾损伤组(SA-AKI组)及脓毒症相关性急性肾损伤+氯沙坦组(SA-AKI+LOS组)。采用盲肠结扎穿孔法建立小鼠脓毒症模型。Sham+LOS组及SA-AKI+LOS组分别于假手术或造模前3 d开始,腹腔注射氯沙坦5 mg/kg,1次/d,连续3 d;Sham组及SA-AKI组腹腔注射等量溶剂。随机取20只小鼠,观察术后7 d生存情况。于假手术或造模后24 h,采用比色法测定血清BUN及Cr浓度,采用ELISA法测定血清TNF-α、IL-6和高迁移率族蛋白B1(HMGB1)浓度;取肾组织,HE染色后光镜下观察病理学结果,并行肾小管损伤评分,采用荧光素酶法测定ATP含量,采用JC-1法测定线粒体膜电位(MMP)水平,采用Western blot法检测动力相关蛋白1(Drp1)及线粒体融合蛋白2(Mfn2)表达。结果与Sham组比较,SA-AKI组及SA-AKI+LOS组生存率降低,血清BUN、Cr、TNF-α、IL-6、HMGB1浓度和肾小管损伤评分升高,肾组织ATP含量及MMP下降,Drp1表达上调,Mfn2表达下调(P<0.05),肾组织发生病理学损伤;与SA-AKI组比较,SA-AKI+LOS组生存率升高,血清BUN、Cr、TNF-α、IL-6、HMGB1浓度和肾小管损伤评分下降,肾组织ATP含量及MMP升高,Drp1表达下调,Mfn2表达上调(P<0.05),肾组织病理学损伤减轻。结论氯沙坦可减轻脓毒症小鼠急性肾损伤,机制可能与促进线粒体融合,抑制线粒体分裂有关。

关键词：氯沙坦脓毒症急性肾损伤线粒体融合线粒体分裂

316L奥氏体不锈钢高温单拉和蠕变行为的实验和晶体塑性模拟研究

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Acta Mechanica Sinica 2024年第2期40卷 268-282页

作者：宋世杰阙前华刘宇杰包陈陆晓翀张旭 Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu610031China School of Aeronautics and Astronautics Sichuan UniversityChengdu610065China

316L奥氏体不锈钢(ASS)因其优异的抗蠕变性和耐腐蚀性被广泛应用于核反应堆中的包壳材料.但由于核反应堆长期处于高温环境,其包壳材料会不断累积蠕变损伤并最终导致性能退化,进而影响设备的安全运行.因此,为保障核反应堆的安全服役,针... 详细信息

316L奥氏体不锈钢(ASS)因其优异的抗蠕变性和耐腐蚀性被广泛应用于核反应堆中的包壳材料.但由于核反应堆长期处于高温环境,其包壳材料会不断累积蠕变损伤并最终导致性能退化,进而影响设备的安全运行.因此,为保障核反应堆的安全服役,针对其包壳材料高温蠕变行为的研究具有重要意义.基于此,我们开展了316L ASS在高温下的单轴拉伸变形和蠕变行为的研究.结果表明,316L ASS的力学响应具有明显的温度依赖性,且在特定的温度范围(723 K-923 K)和应变率(1.3×10−3 s−1)条件下,显示出明显的动态应变时效效应;此外,316L ASS在高温条件下的主要蠕变机制为位错攀移机制,它一方面会影响位错密度的演化,另一方面会影响位错越过障碍物的激活频率.基于316L ASS在高温下的微结构演化机理,我们建立了基于位错机制的晶体塑性本构模型.在该模型中额外考虑了位错攀移机制对刃型位错湮灭、位错偶极子形成和刃型位错越过障碍物的贡献.最终结果表明,该模型能有效地模拟和预测316L ASS在高温条件下的单轴拉伸和蠕变响应,而该研究成果也为316L ASS的蠕变性能评估提供了重要的理论依据.

关键词： 316L奥氏体不锈钢动态应变时效刃型位错位错攀移晶体塑性蠕变性能蠕变行为温度依赖性

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冰箱冷藏室温度场与速度场的协同控制研究

环境技术 2022年第4期40卷 77-84,99页

作者：刘利娜廖爱群宋侃北京理工大学珠海学院工业自动化学院珠海519088

为探究低温密闭流体域的温度场与速度场的协同控制方法,选择一台冷藏室容积为277 L的冰箱开展研究。采用Fluent软件和实验测试相结合的方法,分析了冷藏室内三维温度场与速度场的分布特征,揭示该冰箱冷藏室温度均匀性差,且温度波动大的... 详细信息

为探究低温密闭流体域的温度场与速度场的协同控制方法,选择一台冷藏室容积为277 L的冰箱开展研究。采用Fluent软件和实验测试相结合的方法,分析了冷藏室内三维温度场与速度场的分布特征,揭示该冰箱冷藏室温度均匀性差,且温度波动大的原因。据此提出了一种新型温度场和速度场协同控制方案,探究了进风方式、回风口位置、进风孔型等因素对冷藏室温度分布的影响。结果表明:新型温度场和速度场协同控制方案对提升冷藏室温度均匀性、降低温度波动度效果明显。开机阶段,箱内强制对流形态下垂直、水平温差在1 ℃以内,开机和停机阶段,箱内不同对流形态下温度波动度低于4.8 ℃。

关键词：温度均匀性温度波动性对流形态协同控制