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超声处理对煤泥组分沉降速度的影响

矿产综合利用 2024年第2期45卷 138-143页

作者：张晓彬温欣曹伟伟李忠山谭静唐山工业职业技术学院河北唐山063299 西安科技大学陕西西安710054 陕西省煤炭科学研究所陕西西安710001

这是一篇矿业工程领域的论文。高岭石与蒙脱石是煤泥中存在的主要黏土矿物,而黏土矿物是影响煤泥沉降的主要因素。本文以精煤、高岭石和蒙脱石作为研究对象,首先探索了超声强度、作用时间、超声脉冲间隔三类超声条件对其沉降效果以及絮... 详细信息

这是一篇矿业工程领域的论文。高岭石与蒙脱石是煤泥中存在的主要黏土矿物,而黏土矿物是影响煤泥沉降的主要因素。本文以精煤、高岭石和蒙脱石作为研究对象,首先探索了超声强度、作用时间、超声脉冲间隔三类超声条件对其沉降效果以及絮团直径的影响,实验结果表明:当超声密度为0.4 W/cm^(3),超声作用时间为2 min时,高岭石和蒙脱石的沉降速度都得到了改善,选择合适的超声脉冲间隔时间对样品进行间断超声可以进一步提高其的沉降效果,但是超声处理反而不利于精煤沉降。将精煤、高岭石和蒙脱石试样按2∶1∶1的比例混合制样,改变超声脉冲间隔时间对其进行超声处理,结果表明:对于混合试样,未经超声处理时沉降速度为2.67 cm/min,在超声密度为0.2 W/cm^(3),超声脉冲间隔时间为4 s时作用2 min,沉降速度提高到5.41 cm/min。图像分析与电位表征显示,适当的超声脉冲间隔时间使药剂作用发挥更充分,进而双电层得到最大程度压缩,最终提高了颗粒凝聚和絮团生长效果。

关键词：矿业工程煤泥沉降超声处理絮团

低频脉冲磁场诱导TRPC1改善COVID-19患者康复期下肢的肌肉无力症状

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中国组织工程研究 2024年第16期28卷 2605-2612页

作者：厉中山包义君刘洁孔维签李伟陈琳白石杨铁黎王春露福建师范大学体育科学学院福建省福州市350117 东北大学体育部辽宁省沈阳市110819 中国医科大学附属第四医院辽宁省沈阳市110044 中国医科大学科学试验研究中心辽宁省沈阳市110122 沈阳工业大学信息科学与工程学院辽宁省沈阳市111003 东北大学生命科学与健康学院辽宁省沈阳市110167 辽宁省磁医学检测与治疗专业技术创新中心辽宁省沈阳市110034 首都体育学院北京市100191 北京体育大学冰上运动学院北京市100084

背景:肌肉无力是新型冠状病毒(COVID-19)感染后的常见症状,影响康复期人体日常活动能力。在强度1.5 mT,频率3300 Hz的低频脉冲磁场刺激下可通过诱导和激活经典瞬时感受器电位通1(classical transient receptor potential channel 1,TRPC... 详细信息

背景:肌肉无力是新型冠状病毒(COVID-19)感染后的常见症状,影响康复期人体日常活动能力。在强度1.5 mT,频率3300 Hz的低频脉冲磁场刺激下可通过诱导和激活经典瞬时感受器电位通1(classical transient receptor potential channel 1,TRPC1),提升人体骨骼肌的最大自主收缩力与力量耐力,对肌肉组织产生一系列生理支持效应,该手段是否会改善新型冠状病毒肺炎患者康复期的肌无力症状尚无研究。目的:选用低频脉冲磁场对新型冠状病毒肺炎患者下肢肌群进行磁刺激,以观察该刺激对新型冠状病毒肺炎患者康复期下肢肌群肌无力改善的影响。方法:招募胶体金法抗原检测试剂(COVID-19)为阳性并伴有肌肉无力症状的新型冠状病毒(奥密克戎毒株)感染患者14例,将所有受试者随机分成2组,分别为接受磁场刺激的试验组和接受假治疗的对照组。试验总时长3周,试验组每隔48 h对腿部进行低频脉冲磁刺激,对照组与试验组干预流程一致但给予假刺激,两组患者均不被告知磁刺激仪器是否运行,两组患者共进行9次操作,随后观察两组患者下肢局部肌群最大自主收缩力、腿部爆发力与力量耐力的变化情况。结果与结论:①在采集的8个局部肌群中,试验组患者7个局部肌群在经过3周的低频脉冲磁场刺激,最大自主收缩力值均增长。对照组除3个肌群最大自主收缩力自行增长改善以外,其他肌群肌力无提升。②试验组的左腿前群与双腿后群提升率显著高于对照组。③两组的纵跳摸高高度与膝关节峰值角速度相比试验前测均提升,试验组摸高高度提升率高于对照组。④在疲劳状态下,试验组膝关节峰值角速度下降率显著下降,对照组膝关节峰值角速度下降率无显著性变化;试验组摸高高度下降率显著下降,而对照组摸高高度下降率无显著性变化。⑤上述数据证实,在强度1.5 mT,频率3300 Hz的低频脉冲磁场刺激方案下,新型冠状病毒肺炎患者在康复期经过3周的低频脉冲磁场刺激相比人体自愈过程可使更多的下肢局部肌群肌力获得提升,对基于腿部爆发力的全身协调发力能力及功能状态明显改善。因此,低频脉冲磁场刺激可作为一种改善新冠感染患者下肢肌肉无力症状的有效、非运动的康复手段。

关键词：新型冠状病毒 COVID-19 新型冠状病毒肺炎脉冲磁场经典瞬时感受器电位通道1 TRPC1 肌肉无力

Spatiotemporal control of femtosecond laser filament-triggered discharge and its application in diagnosing gas flow fields

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Plasma Science and Technology 2022年第2期24卷 73-79页

作者： Zhifeng ZHU Bo li Qiang GAO Jiajian ZHU zhongshan li State Key Laboratory of Engines Tianjin UniversityTianjin 300350People's Republic of China College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073People's Republic of China Division of Combustion Physics Lund UniversityLund SE-22100Sweden

Precise control of the discharge in space and time is of great significance for better applications of discharge ***,we used a femtosecond laser filament to trigger and guide a highvoltage DC pulse discharge to achieve spatiotemporal control of the discharge *** space,the discharge plasma is distributed strictly along the channel generated by the femtosecond laser *** breakdown voltage threshold is reduced,and the discharge length is *** time,the electrical parameters such as the electrode voltage and the electrode gap affect discharge delay time and *** optimizing the parameters,we can achieve sub-nanosecond jitter of the *** on the spatiotemporal control of the discharge,we applied filamenttriggered discharge for one-dimensional composition measurements of the gas flow ***,the technique shows great potential in studying the spatiotemporal evolution of discharge plasma.

关键词： femtosecond laser filamentation high voltage discharge discharge plasma spectrum

New Results on Sign Patterns that Allow Diagonalizability

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Journal of Mathematical Research with Applications 2022年第2期42卷 111-120页

作者： Xinlei FENG zhongshan li College of Mathematics and Physics Leshan Normal University Department of Mathematics and Statistics Georgia State University

Characterization of sign patterns that allow diagonalizability has been a long-standing open problem. In this paper, we obtain some sufficient and/or necessary conditions for a sign pattern to allow diagonalizability. Moreover, we determine how many entries need to be changed to obtain a matrix B′∈ Q(A) with rank MR(A) from a matrix B ∈ Q(A) with rank mr(A).Finally, we also obtain some results on a sign pattern matrix in Frobenius normal form that allows diagonalizability.

关键词： sign pattern allowing diagonalizability maximum cycle length minimum rank maximum rank Frobenius normal form

Premixed jet flame characteristics of syngas using OH planar laser induced fluorescence

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Chinese Science Bulletin 2011年第26期56卷 2862-2868页

作者： YANG li WANG ZhiHua ZHU YanQun li zhongshan ZHOU JunHu HUANG ZhenYu CEN KeFa State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China Division of Combustion Physics Lund University Lund P.O. Box 118 S-22100 Sweden

Lean premixed flame characteristics of several typical low calorific value (LCV) syngases (basis CO/H2/CH4/CO2/N2),including bituminous coal,wood residue,corn core,and wheat straw gasification syngas,were investigated using OH planar laser induced fluorescence (PliF) *** radical distributions within the turbulent flame were measured for different turbulence *** structures of syngases were analyzed and characterized with respect to burnt and unburnt regions,flame curvature (sharp cusp),local extinction (holes and penetration),OH reaction layer thickness,wrinkling,and other features,with OH-PliF instantaneous images and statistical *** show that H2 content,LCV,and turbulence intensity are the most effective factors influencing the OH radical intensity and thickness of OH radical *** bituminous coal gasification syngas with relatively higher LCV and H2 content tends to burn out *** changes in thickness of the OH radical layers and signal intensities,the reaction layer can be compressed by intensifying turbulence and thereby the combustion processes of syngas.

关键词：平面激光诱导荧光火焰特性合成气预混 OH自由基轻型商用车喷气 PliF

Deep Neural Network-Based Generation of Planar CH Distribution through Flame Chemiluminescence in Premixed Turbulent Flame

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能源与人工智能(英文) 2023年第2期12卷 22-30页

作者： Lei Han Qiang Gao Dayuan Zhang Zhanyu Feng Zhiwei Sun Bo li zhongshan li State Key Laboratory of Engines Tianjin UniversityTianjin300354PR China China North Engine Research Institute Tianjin300400PR China Centre for Energy Technology School of Mechanical EngineeringThe University of AdelaideAdelaideS.A.5005Australia Division of Combustion Physics Lund UniversityP.O.Box 118LundS22100Sweden

Flame front structure is one of the most fundamental characteristics and, hence, vital for understanding combustion processes. Measuring flame front structure in turbulent flames usually needs laser-based diagnostic techniques, mostly planar laser-induced fluorescence (PliF). The equipment of PliF, burdened with lasers, is often too sophisticated to be configured in harsh environments. Here, to shed the burden, we propose a deep neural network-based method to generate the structures of flame fronts using line-of-sight CH* chemiluminescence that can be obtained without the use of lasers. A conditional generative adversarial network (CGAN) was trained by simultaneously recording CH-PliF and chemiluminescence images of turbulent premixed methane/air flames. Two distinct generators of the C-GAN, namely Resnet and U-net, were evaluated. The former net performs better in this study in terms of both generating snap-shot images and statistics over multiple images. For chemiluminescence imaging, the selection of the camera’s gate width produces a trade-off between the signal-to-noise (SNR) ratio and the temporal resolution. The trained C-GAN model can generate CH-PliF images from the chemiluminescence images with an accuracy of over 91% at a Reynolds number of 5000, and the flame surface density at a higher Reynolds number of 10,000 can also be effectively estimated by the model. This new method has the potential to achieve the flame characteristics without the use of laser and significantly simplify the diagnosing system, also with the potential for high-speed flame diagnostics.

关键词： Turbulent flame front Neural network Conditional generative adversarial nets Laser diagnostics Chemiluminescence

Synergistic injection of the thermosensitive hydrogel and Bi-based alloy bone cement for orthopaedic repair

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Science China(Technological Sciences) 2024年第7期67卷 2153-2163页

作者： liU SiCong li Lei JIANG ChanYuan WANG QianYu DENG zhongshan Key Laboratory of Cryogenic Science and Technology Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Department of Cleft lip and Palate Plastic Surgery HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100144China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China

Low-melting-point alloys have the advantages of good biocompatibility, plasticity, and near-bone mechanical strength, making them suitable as bone defect-filling materials for direct injection into defective bone sites. However, using low-melting-point alloys for orthopedic implants poses the challenge of causing thermal damage to the surrounding bone tissue during injection. In this study, a thermosensitive hydrogel is prepared and synergistically injected into the bone defect site with BiInSn. BiInSn solidifies and releases heat during injection, while the thermosensitive hydrogel absorbs heat and transforms into a gel state,encapsulating BiInSn. Therefore, the surrounding bone tissue is effectively protected from thermal damage. When BiInSn and the thermosensitive hydrogel were injected synergistically, in vitro thermal experiments revealed that the maximum temperature of the surrounding bone tissue reached 42℃. This temperature is below the 47℃ threshold, which causes permanent damage to bone tissues. In vivo experiments demonstrated that rats in the BiInSn-thermosensitive hydrogel group exhibited better recovery at the bone defect sites. These results suggest that the synergistic injection of Bi-based alloy and thermosensitive hydrogel is beneficial in reducing thermal damage to bone tissue, guiding bone tissue growth, and effectively facilitating the repair of bone defects.

关键词： bone defects thermosensitive hydrogel thermal damage to tissue bismuth-based alloy bone cement

Release characteristic of different classes of sodium during combustion of Zhun-Dong coal investigated by laser-induced breakdown spectroscopy

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Science Bulletin 2015年第22期60卷 1927-1934页

作者： Yong He Kunzan Qiu Ronald Whiddon Zhihua Wang Yanqun Zhu Yingzu liu zhongshan li Kefa Cen State Key Laboratory of Clean Energy Utilization Zhejiang University Division of Combustion Physics Lund University

Serious fouling and slagging problems are associated with the combustion of Chinese Zhun-Dong coal due to its high content of sodium （Na）. Understanding the release characteristic of Na during the combustion is essential to viable utilization of this coal. In this work, coal samples were treated with a sequence of solvents： water （H2O）, ammonium acetate （NH4Ac）, hydrochloric acid （HC1）, and the release characteristics of various classes of Na during coal combustion were investigated using the technique of laser-induced breakdown spectroscopy. The relative contribution of various Na classes to the Na release during each combustion stage was found to be similar, in the order of H2O-soluble Na 〉 NHaAcsoluble Na 〉 HCl-soluble Na 〉 insoluble Na. Sodium released during the devolatilization stage can be attributed to each of the sodium classes. After the devolatilization stage, H2O-soluble Na and NHaAc-soluble Na dominated the Na release during both char and ash stages. Over 64 % of the total Na released during combustion comes from the H2O-soluble Na, which suggests that the Na release during the combustion of Zhun-Dong coal can be reduced effectively after treatment by H2O washing.

关键词： Zhun-Dong coal Laser-inducedbreakdown spectroscopy (liBS) - Sodium releaseCombustion Online measurement

The Second Largest Balaban Index(Sum-Balaban Index) of Unicyclic Graphs

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Journal of Mathematical Research with Applications 2017年第4期37卷 391-403页

作者： Wei FANG Yubin GAO Kai FAN zhongshan li School of Instrument and Electronics North University of China Department of Mathematics North University of China Department of Mathematics Southeast University Department of Mathematics & Statistics Georgia State University

Balaban index and Sum-Balaban index were used in various quantitative structureproperty relationship and quantitative structure activity relationship studies. In this paper,the unicyclic graphs with the second largest Balaban index and the second largest SumBalaban index among all unicyclic graphs on n vertices are characterized, respectively.

关键词： Balaban index Sum-Balaban index unicyclic graph