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Stress-assisted corrosion mechanism of 3Ni steel by using gradient boosting decision tree machining learning method

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1311-1321页

作者： Xiaojia Yang Jinghuan jia Qing Li Renzheng Zhu jike Yang Zhiyong Liu Xuequn Cheng Xiaogang Li Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China AECC Key Laboratory of Advanced Corrosion and Protection of Aeronautical Materials AECC Beijing Institute of Aeronautical MaterialsBeijing 100095China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China

Traditional 3Ni weathering steel cannot completely meet the requirements for offshore engineering development,resulting in the design of novel 3Ni steel with the addition of microalloy elements such as Mn or Nb for strength enhancement becoming a *** stress-assisted corrosion behavior of a novel designed high-strength 3Ni steel was investigated in the current study using the corrosion big data *** information on the corrosion process was recorded using the galvanic corrosion current monitoring *** gradi-ent boosting decision tree(GBDT)machine learning method was used to mine the corrosion mechanism,and the importance of the struc-ture factor was *** exposure tests were conducted to verify the calculated results using the GBDT *** indic-ated that the GBDT method can be effectively used to study the influence of structural factors on the corrosion process of 3Ni ***-ferent mechanisms for the addition of Mn and Cu to the stress-assisted corrosion of 3Ni steel suggested that Mn and Cu have no obvious effect on the corrosion rate of non-stressed 3Ni steel during the early stage of *** the corrosion reached a stable state,the in-crease in Mn element content increased the corrosion rate of 3Ni steel,while Cu reduced this *** the presence of stress,the increase in Mn element content and Cu addition can inhibit the corrosion *** corrosion law of outdoor-exposed 3Ni steel is consistent with the law based on corrosion big data technology,verifying the reliability of the big data evaluation method and data prediction model selection.

关键词： weathering steel stress-assisted corrosion gradient boosting decision tree machining learning

Positive effect of ethanol-induced Lactococcus lactis on alcohol metabolism in mice

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Food Science and Human Wellness 2022年第5期11卷 1183-1190页

作者： Sisi Chen Shimin jia Keke Suo Qiaozhen Kang Limin Hao Laizheng Lu Xin Liu Jinyong Huang jike Lu School of Life Sciences Zhengzhou UniversityZhengzhou 450001China Physical Education College Zhengzhou UniversityZhengzhou 450001China The Quartermaster Research Institute of Engineering and Technology Academy of Military Sciences PLA ChinaBeijing 100010China Zhengzhou Mindtek Biotechnology Co. Ltd.Zhengzhou 450001China School of Agricultural Sciences Zhengzhou University 450001China

It is well known that exposure to environmental stresses could enhance the adaptability of bacteria and up-regulate the expression of a variety of oxidative stress-related genes and antioxidant *** is unclear whether the adaptability of microorganisms formed naturally in special environments could transfer to other *** study aimed to evaluate the effects of untreated and ethanol-induced Lactococcus lactis intracellular extracts(U-IE and E-IE)on alcohol metabolism in *** positive effects of E-IE on alcohol metabolism in mice were revealed by the enhanced latency of loss of righting reflex(LORR),the reduced duration of LORR,the decrease of blood alcohol concentration,as well as the elevation of alcohol dehydrogenase(ADH)activities in the stomach and liver ***,the potential benefits of E-IE on the liver were evaluated by biochemical parameters including the activities of serum transaminase,the levels of antioxidant enzymes,and the pathological changes of liver *** present work put forward a new point that appropriate ethanol stress could enhance the intracellular ADH activity of ***,and its intracellular extracts could continue to enhance alcohol metabolism in mice.

关键词： Ethanol stress Intracellular extracts Alcohol dehydrogenase Alcohol metabolism

A modified three-incision approach to treating three-column Lisfranc injuries

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Chinese Journal of Traumatology 2022年第6期25卷 362-366页

作者： Ting-Hu Zhao Han-Xin Chen Bin jia Yun-Bo Bai jike Lu Wei Ren Department of Foot and Ankle Shen Zhen Ping Le Orthopaedic HospitalShenzhen518118Guangdong ProvinceChina Department of Orthopaedic Trauma Shen Zhen Ping Le Orthopaedic HospitalShenzhen518118Guangdong ProvinceChina Department of Orthopedic Surgery United Family HospitalBeijing100015China

Purpose:The most popular surgical approach to manage Lisfranc fracture-dislocations is the double-incision approach,which frequently causes a variety of complications,such as skin necrosis,rotational malreduction of the first tarsometatarsal joint(TMTJ)and lateral column dorsoplantar malreduction of the *** introduce a three-incision approach to treat Lisfranc fracture-dislocations with only minor postoperative complications and good foot ***:We prospectively selected 30 previously healthy patients,ranging from 18 to 60 years of age,but only 23 patients completed the follow-up and thus were finally included,with an average age of 38.1±12.9 *** patients have sustained Lisfranc fracture-dislocations involving all three-column;13.0%(3/23)were Myerson classification type A(medial),47.8%(11/23)were type A(lateral),and 39.1%(9/23)were type *** patients were treated via a three-incision approach:a long incision made along the lateral border of the second ray was used as a working incision to visualize and reduce the first three TMTJs,as well as to apply internal fixation instrumentation;a 2 cm medial incision was made at the medial side of the first TMTJ as an inspecting incision,ensuring good reduction of the first TMTJ in medial and plantar view;another 1 cm inspecting incision was made at the dorsal side of the fourth/fifth TMTJ to prevent sagittal subluxation of the lateral ***±SD was used for quantitative data such as operation time,follow-up time and foot function *** complications were documented,and foot function was evaluated using the American orthopaedic foot&ankle society score,foot function index and Maryland foot score at *** foot function of the injured foot and contralateral foot of the same patient was at the end of follow-up,and independent samplet-test was used for statistical ***:The median operation time was 117.9±14.6 min(range 93-142 min).All complications occurred within three

关键词： Surgical approach Three-incision approach Complication Three-column Lisfranc fracture-dislocation Foot function

架空导线单相触树接地故障的放电引燃机制研究

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电网技术 2023年第3期47卷 1289-1298页

作者：秦际轲宁鑫范松海贾志东清华大学深圳国际研究生院广东省深圳市518055 国网四川省电力公司电力科学研究院四川省成都市610041 电力物联网四川省重点实验室(国网四川省电力公司) 四川省成都市610041

近年来世界范围内因电气故障引发森林火灾的案例时有发生,严重威胁到民众的生命财产安全。该文针对架空导线单相触树引燃植被的事故,分析了高压电场作用下植被的引燃机制,并建立树线接触模拟试验平台,得到植被引燃过程中典型的物理特征... 详细信息

近年来世界范围内因电气故障引发森林火灾的案例时有发生,严重威胁到民众的生命财产安全。该文针对架空导线单相触树引燃植被的事故,分析了高压电场作用下植被的引燃机制,并建立树线接触模拟试验平台,得到植被引燃过程中典型的物理特征和电气特征。结果表明:1)放电引燃过程可分为4个典型的阶段并和泄漏电流的变化相对应;2)电流持续导通时间和初始电流是决定引燃能否发生和发展的关键;3)接触部位和炭化通道上的电弧能促进火焰的发展,并导致植被绝缘能力进一步下降;4)引燃过程中存在“炭化效应”和“烹饪效应”的博弈,这种竞争导致电气信号在时域发生变化;5)炭化通道呈典型的电树枝状,树枝中的导电通道集中于表皮和主干的交界面处。从试验结果可知,高压电场下的植被引燃有阶段性发展的特点,分析放电引燃的机制,准确提取并识别植被燃烧各阶段特征,将有助于改善故障检测技术。

关键词：导线触树故障炭化通道电弧引燃过程山火

双级式光伏并网发电前级变换器系统建模与控制器参数设计

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可再生能源 2016年第3期34卷 360-367页

作者：王生铁贾立宾张计科温素芳内蒙古工业大学电力学院内蒙古呼和浩特010080 内蒙古电子信息职业技术学院内蒙古呼和浩特010070

针对双级式光伏并网发电前级变换器系统功率电压双闭环MPPT结构的控制器参数设计问题,基于前级变换器系统的等效电路,采用状态空间平均法建立了系统的非线性模型,进而采用平衡点附近线性化方法得到其线性模型。根据对象特性引入控制器结... 详细信息

针对双级式光伏并网发电前级变换器系统功率电压双闭环MPPT结构的控制器参数设计问题,基于前级变换器系统的等效电路,采用状态空间平均法建立了系统的非线性模型,进而采用平衡点附近线性化方法得到其线性模型。根据对象特性引入控制器结构,在频率特性和根轨迹分析的基础上,给出了前级控制器参数的系统化设计方法。12 k W双级式光伏并网发电系统仿真结果表明,在标准光强和模拟自然条件光强变化时,该控制器能快速实现前级MPPT跟踪控制及单位功率因数并网控制,获得了良好的动静态性能。

关键词：双级式并网变换器建模状态空间平均法参数设计

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CT椎间盘造影诊断腰椎间盘突出症

中华骨科杂志 1995年第3期15卷 158-160页

作者：欧阳甲方国华路继科韩开南米吉提新疆医学院一附院骨科

７３例临床疑诊为腰椎间盘突出症的患者作了脊髓造影和ＣＴ椎间盘造影检查。手术治疗５３例，其中突出４５例５１个间隙。两种方法的阳性率分别为７０％和９２％。ＣＴ椎间盘造影影像能清晰显示突出物的大小、部位，硬膜囊神经根受压、... 详细信息

７３例临床疑诊为腰椎间盘突出症的患者作了脊髓造影和ＣＴ椎间盘造影检查。手术治疗５３例，其中突出４５例５１个间隙。两种方法的阳性率分别为７０％和９２％。ＣＴ椎间盘造影影像能清晰显示突出物的大小、部位，硬膜囊神经根受压、造影剂充填、关节突退变情况。当其它辅助检查仍不能明确定性和定位诊断时，ＣＴ椎间盘造影可帮助确诊，尤其对Ｌ＿５－Ｓ＿１椎间盘突出意义更大。

关键词：椎间盘造影椎间盘突出腰椎诊断

健康信念模式下HIV/AIDS患者安全套使用影响因素分析

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中国艾滋病性病 2022年第5期28卷 545-549页

作者：贾思艳黄玉玲钟世勇余彬吉克尔沙余刚王菊吉克春农李天露杨淑娟四川大学华西公共卫生学院/四川大学华西第四医院成都610041 四川省疾病预防控制中心成都610041 布拖县疾病预防控制中心四川布拖615350 四川大学华西第二医院成都610041 凉山州疾病预防控制中心四川西昌615000

目的了解HIV/AIDS患者安全套使用情况,并基于健康信念模式分析其影响因素。方法于2019年6-12月对采用整群抽样方法选取的研究对象进行面对面问卷调查。采用二分类Logistic回归,分析健康信念对HIV/AIDS患者坚持使用安全套的影响。结果过... 详细信息

目的了解HIV/AIDS患者安全套使用情况,并基于健康信念模式分析其影响因素。方法于2019年6-12月对采用整群抽样方法选取的研究对象进行面对面问卷调查。采用二分类Logistic回归,分析健康信念对HIV/AIDS患者坚持使用安全套的影响。结果过去6个月,有34.1%(140/411)的研究对象在与固定性伴发生性行为时坚持使用安全套,在有偶遇性行为的13人中,仅5人坚持使用安全套;健康信念模式中感知威胁(β=0.38,P<0.001)、行为线索(β=0.61,P<0.001)和自我效能(β=0.49,P<0.001)与HIV/AIDS患者坚持使用安全套呈正相关,感知障碍(β=-0.30,P<0.001)与HIV/AIDS患者坚持使用安全套呈负相关。结论提高HIV/AIDS患者安全套使用信心,强化安全套使用信息提示,消除其在使用过程中遇到的社会、文化障碍,对于促进安全套使用及预防艾滋病在家庭内及家庭外传播都具有重要意义。

关键词：艾滋病病毒感染者/艾滋病患者健康信念模式安全套使用

不同破壁方法对灵芝孢子粗多糖抗氧化活性的影响

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食品科学 2017年第17期38卷 101-106页

作者：董扬郝利民刘宇琪张黎明鲁吉珂江庆伍贾士儒天津科技大学工业发酵微生物教育部重点实验室天津300457 军需装备研究所北京100010 郑州大学生命科学学院河南郑州450001 安徽金寨乔康药业有限公司安徽六安237300

采用1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl，DPPH）自由基清除法、羟自由基清除法、2,2’-联氮基双（3-乙基苯并噻唑啉-6-磺酸）二铵盐自由基（2,2’-azinobis(3-ehtylbenzothiazolin-6-sulfnicacid)diammonium salt，ABTS＋·）清除法和铁氰化钾法以及酵母细胞氧化损伤保护模型，分别对未破壁灵芝孢子（unbroken Ganoderma lucidum spore，UGS）、机械法破壁灵芝孢子（mechanically broken Ganoderma lucidum spore，MGS）、生物法与机械法复合破壁的灵芝孢子（biologically and mechanically broken Ganoderma lucidum spore，BGS）提取粗多糖进行体外抗氧化活性评价。结果表明，3种处理方法的灵芝孢子粗多糖表现出不同的抗氧化活性，且抗氧化活性与多糖质量浓度呈一定效量关系，多糖质量浓度越高，抗氧化活性越强。BGS所得粗多糖对DPPH自由基、羟自由基、ABTS＋.的清除能力以及还原力在3种处理方法中均为最强。多糖质量浓度为5.0mg/mL时，对3种自由基的清除率分别为84.6%、91.0%、99.9%，还原力为1.09；BGS所得粗多糖对紫外损伤酵母细胞保护能力也相对较强。表明BGS粗多糖具有较高的抗氧化活性。

关键词：灵芝孢子生物破壁机械破壁粗多糖抗氧化

3D打印技术在船用柴油机领域的应用前景分析

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柴油机 2015年第2期37卷 1-5页

作者：李佳张纪可冯明志七一一研究所上海201108

介绍了3D打印技术的原理、国内发展现状及优缺点,分析了其在船用柴油机领域的应用前景。指出:3D打印技术可以有效地降低船用柴油机研发成本、缩短研发周期,具有广阔的发展前景。

关键词： 3D打印船用柴油机增材制造