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Workability and Strength of Ceramsite Self-Compacting Concrete with Steel Slag Sand

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Journal of Renewable Materials 2023年第2期11卷 881-904页

作者： Suiwei Pan Anqi Ren yongli peng Min Wu Wanguo Dong Chunlin Liu Depeng Chen School of Construction Engineering Ma’anshan UniversityMa’anshan243100China School of Architectural and Civil Engineering Anhui University of TechnologyMa’anshan243032China School of Management Science and Engineering Anhui University of TechnologyMa’anshan243032China

This study focuses on the workability and compressive strength of ceramsite self-compacting concrete with fine aggregate partially substituted by steel slag sand(CSLSCC)to prevent the pollution of steel slag in the environment.The SF,J-ring,visual stability index,and sieve analysis tests are primarily employed in this research to investigate the workability of freshly mixed self-compacting concrete containing steel slag at various steel slag sand replacement rates.The experiment results indicate that CSLSCC with the 20%volume percentage of steel slag(VPS)performs better workability,higher strength,and higher specific strength.The 7-day compressive strength of CSLSCC with the 0.4 of the water-binder ratio(W/B),decreases with the increase of steel slag content,while the 28-day compressive strength increases significantly.The ceramsite self-compacting concrete with good comprehensive performance can be obtained when the substitution rate of steel slag sand for fine aggregate is less than 20%(volume percentage).

关键词： Steel slag ceramsite self-compacting concrete workability compressive strength

儿童Hughes-Stovin综合征合并动脉导管未闭CT表现1例

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中华放射学杂志 2024年第3期58卷 337-338页

作者：曹永丽姚兴凤彭芸国家儿童医学中心、首都医科大学附属北京儿童医院影像中心北京100045 国家儿童医学中心、首都医科大学附属北京儿童医院病理科北京100045

该文报告1例儿童Hughes-Stovin综合征患者的CT表现。患儿男,12岁,间断发热、咳嗽,咳痰1年余,痰中带血2个月。CT表现为双侧多发肺动脉瘤伴右下叶肺出血,合并动脉导管未闭及赘生物形成。经激素和免疫抑制剂治疗后好转。

关键词：体层摄影术 X线计算机肺动脉瘤肺出血动脉导管未闭

Multiple Random Forests Based Intelligent Location of Single-phase Grounding Fault in Power Lines of DFIG-based Wind Farm

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Journal of Modern Power Systems and Clean Energy 2022年第5期10卷 1152-1163页

作者： yongli Zhu Hua peng School of Electrical and Electronic Engineering North China Electric Power UniversityBaoding 071003China

To address the problems of wind power abandonment and the stoppage of electricity transmission caused by a short circuit in a power line of a doubly-fed induction generator(DFIG) based wind farm, this paper proposes an intelligent location method for a single-phase grounding fault based on a multiple random forests(multi-RF) algorithm. First, the simulation model is built, and the fundamental amplitudes of the zerosequence currents are extracted by a fast Fourier transform(FFT) to construct the feature set. Then, the random forest classification algorithm is applied to establish the fault section locator. The model is resampled on the basis of the bootstrap method to generate multiple sample subsets, which are used to establish multiple classification and regression tree(CART) classifiers. The CART classifiers use the mean decrease in the node impurity as the feature importance,which is used to mine the relationship between features and fault sections. Subsequently, a fault section is identified by voting on the test results for each classifier. Finally, a multi-RF regression fault locator is built to output the predicted fault distance. Experimental results with PSCAD/EMTDC software show that the proposed method can overcome the shortcomings of a single RF and has the advantage of locating a short hybrid overhead/cable line with multiple branches. Compared with support vector machines(SVMs)and previously reported methods, the proposed method can meet the location accuracy and efficiency requirements of a DFIG-based wind farm better.

关键词： Doubly-fed induction generator(DFIG)based wind farm power line multiple random forests(multi-RF) single-phase grounding fault fault location

低温等离子体空气净化器在高速公路收费岗亭的干预效果分析

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环境与职业医学 2024年第5期41卷 474-481页

作者：刘松荣周世军肖燕萍周鹏晏致涛马非钟永力蔡姣刘炜浙江交投高速公路运营管理有限公司技术研发中心浙江杭州310020 重庆科技大学建筑工程学院重庆401331 健康环境研究院重庆401331 重庆市能源投资集团科技有限责任公司重庆400061

[背景]高速公路收费站空气污染严重,收费人员存在较高的职业暴露风险,亟须研发适用于高速公路收费岗亭气载颗粒物和微生物病原体的净化方法。[目的]验证低温等离子体空气净化器对高速公路收费岗亭室内气载颗粒物和微生物的净化效果。基... 详细信息

[背景]高速公路收费站空气污染严重,收费人员存在较高的职业暴露风险,亟须研发适用于高速公路收费岗亭气载颗粒物和微生物病原体的净化方法。[目的]验证低温等离子体空气净化器对高速公路收费岗亭室内气载颗粒物和微生物的净化效果。基于对照干预实验设计,选取某高速公路收费站三个收费岗亭作为测点,开展6 d的现场对照干预实验(无干预期:前3 d未开启低温等离子体净化器;干预期:后3 d每天9:00-17:00开启净化器)。实验期间持续监测室内外等效直径小于2.5μm(PM_(2.5))和小于10μm(PM_(10))的可吸入颗粒物浓度;每天上午(9:00)、中午(12:00)和下午(17:00),使用浮游微生物采样器采集收费岗亭室内外空气样品,分析气载细菌总数;每天9:00-17:00采用智能中流量颗粒物采样器持续采集最外侧出站口室内的气载颗粒样品,使用基因测序分析样品内含细菌和真菌种属明细及其相对丰度。采用独立样本t检验比较干预期和无干预期室内气载PM_(2.5)、PM_(10)和细菌总数的浓度差异;采用α多样性分析、β多样性分析和t检验(两组比较),比较干预期3 d和无干预期3 d气载颗粒样品内含细菌和真菌具体种属及样品内含典型致病细菌和真菌病原体种属的物种多样性和相对丰度差异,以反映低温等离子体空气净化器对气载PM_(2.5)、PM_(10)和微生物的净化效果。[结果]干预期室内PM_(2.5)和PM_(10)浓度及细菌总数的均值均低于无干预期室内均值(P<0.01或P<0.001);干预期PM_(2.5)和PM_(10)的室内浓度/室外浓度值(I/O)均低于无干预期(P<0.001);但干预期细菌总数的I/O值与无干预期比较,差异无统计学意义。以上午9:00收费岗亭室内PM_(2.5)的平均浓度为基准,中午12:00和下午17:00的室内PM_(2.5)平均净化率分别为49.0%和46.1%,PM_(10)为49.7%和45.4%,细菌总数为50.8%和49.9%。β多样性分析显示干预期和无干预期细菌种水平,真菌属水平和种水平上的物种组成成分均存在差异。与无干预期相比,干预期颗粒样品内含乳杆菌属等10种细菌和圆酵母菌属等7种真菌的相对丰度更低,但干预期枝孢霉科未分类属、多臂菌属和尾孢菌属真菌的丰度更高(均P<0.05)。对于典型致病菌,干预期乳杆菌属细菌和狭窄梭菌属细菌的相对丰度分别降低了73.5%和86.9%,干预期篮状菌属真菌降低了53.5%,差异均有统计学意义(P<0.05)。[结论]低温等离子体空气净化器对高速公路收费岗亭室内气载PM_(2.5)、PM_(10)和浮游细菌具有较好的净化效果,但对室内气载颗粒内含部分真菌的净化作用可能有限。

关键词：低温等离子体收费岗亭可吸入颗粒物细菌总数基因测序净化效果

The superhydrophobic sponge decorated with Ni-Co double layered oxides with thiol modification for continuous oil/water separation

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Chinese Journal of Chemical Engineering 2023年第2期54卷 296-305页

作者： Xiaodong Yang Na Yang Ziqiang Gong Feifei peng Bin Jiang yongli Sun Luhong Zhang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

In this paper, the superhydrophobic polyurethane sponge(SS-PU) was facilely fabricated by etching with Jones reagent to bind the nanoparticles of Ni-Co double layered oxides(LDOs) on the surface, and following modification with n-dodecyl mercaptan(DDT). This method provides a new strategy to fabricate superhydrophobic PU sponge with a water contact angle of 157° for absorbing oil with low cost and in large scale. It exhibits the strong absorption capacity and highly selective characteristic for various kinds of oils which can be recycled by simple squeezing. Besides, the as-prepared sponge can deal with the floating and underwater oils, indicating its application value in handling oil spills and domestic oily wastewater. The good self-cleaning ability shows the potential to clear the pollutants due to the ultralow adhesion to water. Especially, the most important point is that the superhydrophobic sponge can continuously and effectively separate the oil/water mixture against the condition of turbulent disturbance by using our designed device system, which exhibit its good superhydrophobicity, strong stability.Furthermore, the SS-PU still maintained stable absorption performance after 150 cycle tests without losing capacity obviously, showing excellent durability in long-term operation and significant potential as an efficient absorbent in large-scale dispose of oily water.

关键词： Superhydrophobic sponge Ni-Co double layered oxides Thiol modification Oil absorption Oil/water separation

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重型矿车多功能移动顶升装置及其强度分析

矿山机械 2024年第6期52卷 17-23页

作者：辛昊天赵鹏朱枫姜永利郭鹏达国能宝日希勒能源有限公司设备维修中心内蒙古呼伦贝尔021000

重型矿车作为露天矿山重要的物料运输装备,其工作环境恶劣,长时间的运输作业会加速轮胎老化、磨损。目前,重型矿车轮胎的更换以及检查工作主要是采用传统的液压顶升装置来实现,需依靠大量的人力和辅助设备,导致维修效率低、安全性能差... 详细信息

重型矿车作为露天矿山重要的物料运输装备,其工作环境恶劣,长时间的运输作业会加速轮胎老化、磨损。目前,重型矿车轮胎的更换以及检查工作主要是采用传统的液压顶升装置来实现,需依靠大量的人力和辅助设备,导致维修效率低、安全性能差。为解决以上问题,研发了一款融合人工举升和液压举升优势的多功能举升装置。该设备可通过千斤顶、剪叉伸缩装置和机械支撑块3部分的协同配合,实现对重型矿车前后方位不同姿态的同步顶升,满足大多数型号重型矿车顶升作业的要求。基于有限元分析方法对设备关键零部件进行强度分析和理论验证,结果表明:该设备满足设计使用要求,最大举升载荷为2548 kN,最大举升行程为0.85 m,具有高承载性能和良好的适应性,能够实现对多种型号重型矿车的快速辅助维修,提高了维修工人更换和检查巨型轮胎的工作效率。

关键词：露天矿山重型矿车移动顶升装置强度分析

Mechanical compression management of the right middle cerebral artery inferior trunk using a stent during coil embolization of middle cerebral artery aneurysms:A case report and literature review

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Journal of Interventional Medicine 2023年第3期6卷 126-129页

作者： Zhengyu Wang Zhiqing peng Liang Chen Wanbin Li yongli Wang Department of Interventional Radiology The Sixth People's Hospital South CampusShanghai Jiao Tong UniversityShanghaiChina

Endovascular coil embolization is a minimally invasive,rapid,and effective method for the treatment of intracranial aneurysms.However,complications associated with coil embolization,such as intraoperative aneurysm rupture or arterial occlusion,should be promptly managed during the procedure to avoid catastrophic consequences.This study presents a case of mechanical compression management of the right middle cerebral artery(MCA)inferior trunk during coil embolization for bilateral MCA aneurysms.The inferior trunk of the right MCA was abruptly occluded due to mechanical compression during coil embolization of the right MCA bifurcation aneurysm.A Solitaire AB stent(4×20 mm,Covidien/Medtronic,Dublin,Ireland)was implanted in the inferior trunk of the right MCA after tirofiban was injected via a microcatheter,and the right inferior trunk was recanalized.The patient also underwent coil embolization of the left MCA bifurcation aneurysm,without any complications.It is crucial to recognize compressive occlusion of adjacent aneurysm branches to avoid severe complications during intracranial aneurysm embolization.Stent placement is a rescue treatment option for recanalization of an occluded artery.

关键词： Endovascular coil embolization Intracranial aneurysm Mechanical compression Stent

A Super-robust Armoured Superhydrophobic Surface with Excellent Anti-icing Ability

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Journal of Bionic Engineering 2023年第5期20卷 1891-1904页

作者： peng Wang Hui Zhao Boyuan Zheng Ximei Guan Bin Sun yongli Liao Ying Yue Wei Duan Haimin Ding School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBaoding071000China Hebei Key Laboratory of Electric Machinery Health Maintenance and Failure Prevention North China Electric Power UniversityBaoding071003China Key Laboratory of Icing and Anti/De-Icing China Aerodynamics Research and Development CenterMianyang621000SichuanChina Electric Power Research Institute China South Power GridGuangzhouChina

It has been proved that the construction of interconnected armour on superhydrophobic surface could significantly enhance the mechanical robustness.Here,a new kind of armour with frame/protrusion hybrid structure was achieved by nanosecond laser technology.Then,this armoured superhydrophobic surface demonstrated excellent durability,which could withstand linear abrasion(~3 N press)800 cycles,water jet test(1.0 MPa pressure)40 times and 100℃treatment 18 days.Particularly,the armoured superhydrophobic sample shows outstanding anti-icing ability,which can speed up the supercooled water dropping(no adhesion within 2 h),increase the freezing delay time by~3 times and maintain low adhesion force(less than 35 kPa)after 30 icing/de-icing cycles.Further finite element analysis and theoretical modeling proved that the developed frame/protuberance hybrid structure could effectively enhance the durability.The relatively low surface accuracy in this study can significantly reduce processing cost,which provides a bright future for the practical application of armour superhydrophobic materials.

关键词： Bionic coating Superhydrophobic Robust Armour Anti-icing

Electroacupuncture Pretreatment at Neiguan (PC 6) attenuates autophagy in rats with myocardial ischemia reperfusion through the phosphatidylinositol 3-kinase-Akt-mammalian target of rapamycin pathway

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Journal of Traditional Chinese Medicine 2021年第3期41卷 455-462页

作者： HAN yongli CHEN Song peng Xingming Department of Acupuncture and Moxibustion Hubei University of Traditional Chinese MedicineWuhan 430060China Hubei Provincial Collaborative Innovation Center of Preventive Treatment by Acupuncture and Moxibustion Wuhan430060China Jingzhou second people's Hospital TjingZhou 4300434China Institute of Internal medicine Huangjiahu Hospital of Hubei University of Traditional Chinese MedicineWuhan 430065China

OBJECTIVE: To investigate the protective efficacy of electroacupuncture(EA) pretreatment at Neiguan(PC6) on myocardial ischemia-reperfusion(I/R) in rats.METHODS: Fifty rats were randomly divided into five groups(n = 10): sham operation group, model group(underwent in vivo myocardial I/R), EA pretreatment group [EA at Neiguan(PC 6) 1 week before I/R], wortmannin group(1 week before I/R, the PI3K inhibitor, wortmannin, was injected), EA pretreatment + wortmannin group(both pretreatments were performed simultaneously). After establishing the I/R model, 2,3,5-triphenyltetrazolium chloride(TTC) staining was used to analyze the weight and area of the myocardial infarction tissue.The biosignal and pressure test system was used to determine the left ventricular systolic mean pressure(LVSP), left ventricular end-diastolic pressure(LVEDP), fractional shortening(FS), and ejection fraction(EF). Ultraviolet spectrophotometry was used to determine the expression of creatine kinase(CK)-MB, inducible nitric oxide synthase(i NOS), and total antioxidant capacity(T-AOC) in the serum. The expression of autophagy-related protein 13(ATG13), mammalian target of rapamycin(m TOR), and phosphatidylinositol 3-kinase(PI3K) in cardiac muscle cells was determined by immunofluorescence. Hematoxylin and eosin staining was used to observe autophagy-related pathological changes in rat cardiomyocytes, and ultrastructural changes of cardiomyocytes were examined by transmission electron microscopy.RESULTS: In this study, the infarction size and tissue weight of the EA pretreatment group were decreased compared with the model group(P <0.0001). Furthermore, compared with the model group, the LVEDP values of the EA pretreatment group were significantly reduced(P = 0.0091), and the LVSP, FS, and EF values were slightly increased (P = 0.0007, 0.0020, 0.0031). EA pretreatment also significantly decreased the expression of CK-MB and i NOS, while it increased the expression of T-AOC in the serum of rats with I/R injury(P <0.0001). Furthermore, EA pretreatme

关键词： electroacupuncture myocardial reperfusion injury phosphatidylinositol 3-kinase TOR serine-threonine kinases autophagy