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裂隙对含孔洞岩体力学特性的影响的试验和数值模拟研究

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地质灾害与环境保护 2024年第2期35卷 77-84页

作者：丁尧林国进张程四川省公路规划勘察设计研究院有限公司成都610041 成都理工大学环境与土木工程学院成都610059

为研究单轴压缩状态下裂隙对含孔洞岩体的力学特性的影响,对含孔洞及预制单一裂隙的水泥砂浆试件进行单轴压缩试验及数值模拟,研究预制裂隙倾角i、预制裂隙与孔洞距离m、预制裂隙长度l对试件的力学特性的影响。研究结果表明:(1)当固定... 详细信息

为研究单轴压缩状态下裂隙对含孔洞岩体的力学特性的影响,对含孔洞及预制单一裂隙的水泥砂浆试件进行单轴压缩试验及数值模拟,研究预制裂隙倾角i、预制裂隙与孔洞距离m、预制裂隙长度l对试件的力学特性的影响。研究结果表明:(1)当固定其它参数不变时,抗压强度的试验值和数值模拟值随l的增加基本呈逐渐减小的趋势;当固定其它参数不变时,抗压强度的试验值和数值模拟值随裂隙倾角i的变化规律并不固定;固定其它参数不变时,抗压强度的试验值和数值模拟值随距离m的变化规律并不固定。(2)预制裂隙倾角的大小、预制裂隙至圆孔的距离m、预制裂隙长度l的大小对试件的主裂隙发展方向、破坏模式有影响。

关键词：类岩体预制裂隙力学特性

诱导肝星状细胞铁死亡在肝纤维化防治中的研究进展

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中国中药杂志 2024年第9期49卷 2281-2289页

作者：牛媛媛樊泽坤汪龙德李正菊杜晓娟胥文娟郭林静甘肃中医药大学甘肃兰州730000 甘肃中医药大学附属医院甘肃兰州730020 甘肃省中医院甘肃兰州730050

肝纤维化是慢性肝病进展的关键病理阶段,若本病失治误治,则可进一步恶化为肝衰竭事件,严重影响患者生活质量,并伴随沉重医疗成本消耗。肝星状细胞(hepatic stellate cell,HSC)活化引发细胞外基质(extracellular matrix,ECM)沉积是肝纤... 详细信息

肝纤维化是慢性肝病进展的关键病理阶段,若本病失治误治,则可进一步恶化为肝衰竭事件,严重影响患者生活质量,并伴随沉重医疗成本消耗。肝星状细胞(hepatic stellate cell,HSC)活化引发细胞外基质(extracellular matrix,ECM)沉积是肝纤维化的重要驱动因素,而铁死亡是活化HSC清除或逆转为失活表型的有效策略,因此通过调节铁死亡来抑制HSC的激活与增殖是治疗本病的关键,进一步衍生出诱导HSC铁死亡(包括RNA结合蛋白、非编码RNA、化学制品、中药活性组分)以干预肝纤维化的前景方向。基于此,该文以活化HSC引发ECM沉积为切入点,重点梳理总结诱导HSC铁死亡在延缓肝纤维化进程中的作用机制,以期能不断丰富肝纤维化的临床实践,并为下一步的基础研究提供参考依据。

关键词：肝纤维化 HSC活化 ECM沉积铁死亡中药活性组分非编码RNA

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Effect of nanocomposite pour point depressant EVAL/CNT on flow properties of waxy crude oil

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Petroleum Science 2023年第6期20卷 3807-3818页

作者： Yang Liu Zheng-Nan Sun Sheng-Zhu Ji Yi-Hai Yang Jian-Qi Xu guo-lin jing Provincial Key Laboratory of Oil&Gas Chemical Technology College of Chemistry&Chemical EngineeringNortheast Petroleum UniversityDaqing163318HeilongjiangChina No.8 Oil Production Plant Engineering Technology Brigade Daqing OilfieldDaqing163514HeilongjiangChina

The nanocomposite EVAL-CNT was produced by chemical grafting in the solution system through the esterification of ethylene-vinyl alcohol copolymer (EVAL) and carboxylated multi-walled carbon nanotubes (O-MWCNT), and its structural properties were characterized. The improvement of the rheological properties of the waxy oil system by the novel pour point depressant was investigated using macroscopic rheological measurements and microscopic observations. The results showed that EVAL-CNT nanocomposite pour point depressant (PPD) could significantly reduce the pour point and improve the low temperature fluidity of crude oil and had better performance than EVAL-GO at the same addition level. The best effect was achieved at the dosing concentration of 400 ppm, which reduced the pour point by 13 ℃ and the low-temperature viscosity by 85.4%. The nanocomposites dispersed in the oil phase influenced the precipitation and crystallization of wax molecules through heterogeneous crystallization templates, which led to the increase of wax crystal size and compact structure and changed the wax crystal morphology, which had a better effect on the rheological properties of waxy oil.

关键词： Pour point depressant Carbon nanotubes Nanocomposites Waxy crude oil Rheological behavior

Characteristics and stability of oxide+carbonitride in H13 steel at 1250℃

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Journal of Iron and Steel Research(International) 2024年第1期31卷 134-142页

作者： Xiao-lin Sun Han-jie guo jing guo Fei Wang Dong Xu Gao-yang Song Shuai Wang School of Materials Science and Engineering Hebei University of EngineeringHandan056038HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China High Temperature Materials Research Institute Central Iron and Steel Research Institute Co.Ltd.Beijing100081China Technology Innovation Center for High Quality Cold Heading Steel of Hebei Province Hebei University of EngineeringHandan056038HebeiChina

The morphology,size,quantity,and composition of complex oxide+carbonitride in H13 steel held at 1250℃for 5,10,and 15 h were *** results show that the ratio and number of complex carbonitrides with cores in H13 steel are gradually increased when holding at 1250℃compared with those in the original H13 steel,and the core size *** are one or more oxide cores in(Ti_(x),V_(1-x))(Cy,N_(1-y)),including xCaO·zAl_(2)O_(3),xCaO·yMgO·zAl_(2)O_(3),and CaO after holding at 1250℃,in addition to MgO·Al_(2)O_(3)and Al_(2)O_(3)in the original *** equilibrium temperature for(Ti_(x),V_(1-x))(Cy,N_(1-y))precipitation at the solidification front and decomposition in the solid state was theoretically analyzed,which was affected by the x value and the product of Ti and N contents in H13 ***,the composition of(Ti_(x),V_(1-x))(Cy,N_(1-y))is influenced by the oxide *** is convinced that(Ti_(x),V_(1-x))(Cy,N_(1-y))with oxide cores has a higher stability,especially for oxides with a high Al_(2)O_(3)*** treatment at high temperature facilitates a more reasonable analysis of oxide+carbonitride,and the generation mechanism of oxide+carbonitride was discussed.

关键词： Complex carbonitride Decomposition Oxide core Characteristic Stability

MADRL-based UAV swarm non-cooperative game under incomplete information

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Chinese Journal of Aeronautics 2024年第6期37卷 293-306页

作者： Ershen WANG Fan LIU Chen HONG jing guo lin ZHAO Jian XUE Ning HE School of Electronic and Information Engineering Shenyang Aerospace UniversityShenyang 110136China College of Robotics Beijing Union UniversityBeijing 100101China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China College of Smart City Beijing Union UniversityBeijing 100101China

Unmanned Aerial Vehicles(UAVs)play increasing important role in modern *** this paper,considering the incomplete observation information of individual UAV in complex combat environment,we put forward an UAV swarm non-cooperative game model based on Multi-Agent Deep Reinforcement Learning(MADRL),where the state space and action space are constructed to adapt the real features of UAV swarm air-to-air *** multi-agent particle environment is employed to generate an UAV combat scene with continuous observation *** recently popular MADRL methods are compared extensively in the UAV swarm noncooperative game model,the results indicate that the performance of Multi-Agent Soft Actor-Critic(MASAC)is better than that of other MADRL methods by a large *** swarm employing MASAC can learn more effective policies,and obtain much higher hit rate and win *** under different swarm sizes and UAV physical parameters are also performed,which implies that MASAC owns a well generalization ***,the practicability and convergence of MASAC are addressed by investigating the loss value of Q-value networks with respect to individual UAV,the results demonstrate that MASAC is of good practicability and the Nash equilibrium of the UAV swarm non-cooperative game under incomplete information can be reached.

关键词： UAV swarm Reinforcement learning Deep learning Multi-agent Non-cooperative game Nash equilibrium

Thermodynamic and experimental study of high-temperature roasting of blast furnace gas ash for recovery of metallic zinc and iron

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Journal of Iron and Steel Research(International) 2024年第1期31卷 108-120页

作者： Zi-han Wang jing guo Han-jie guo Bin Li School of Metallurgical Engineering University of Science and Technology BeijingBeijing100083China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina

A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in detail by using ther-modynamic equilibrium calculation and the principle of minimum free *** results showed that the main reaction in the system is the reduction of ZnFe_(2)_(4)and iron *** the full temperature range,iron oxides were more easily reduced than zinc *** of the amount of CO contained in the system,the reduction of ZnO to Zn was difficult to proceed below the boiling point(906℃)of *** the reduction temperature is below 906℃,the reduction process of zinc ferrate was ZnFe_(2)_(4)→ZnO;when the reduction temperature is above 906℃,its reduction process becomed ZnFe_(2)_(4)→ZnO→Zn(g).The metallization and dezincification rates of the BFA gradually increased with increasing reaction *** the C/O ratio increased,the metallization and dezincification rates first increased and then *** effect of reduction time on BFA reduction was similar to that of reaction temperature.

关键词： Blast furnace gas ash Thermodynamics Zinc removal Iron reduction High-temperature reduction roasting Integrated utilization

Innovations in metallurgical and materials processes:advancing liquid theory and honoring ***-jie guo's contributions to physical chemistry in metallurgy

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Journal of Iron and Steel Research(International) 2024年第1期31卷 1-2页

作者： Shuai Liu jing guo Han-jie guo School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China

Spanning three decades,***-jie guo's research group has dedicated itself to exploring the fundamental theories and practical applications of physical chemistry within the realm of *** under the assumption that molecul... 详细信息

关键词： chemistry liquid complexes

Meibomian glands segmentation in infrared images with limited annotation

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 401-407页

作者： Jia-Wen lin ling-Jie lin Feng Lu Tai-Chen Lai jing Zou lin-ling guo Zhi-Ming lin Li Li College of Computer and Data Science Fuzhou UniversityFuzhou 350108Fujian ProvinceChina Fujian Provincial Key Laboratory of Networking Computing and Intelligent Information Processing Fuzhou UniversityFuzhou 350108Fujian ProvinceChina Shengli Clinical Medical College of Fujian Medical University Fuzhou 350001Fujian ProvinceChina Department of Ophthalmology Fujian Provincial Hospital South BranchFujian Provincial HospitalFuzhou 350001Fujian ProvinceChina

●AIM:To investigate a pioneering framework for the segmentation of meibomian glands(MGs),using limited annotations to reduce the workload on ophthalmologists and enhance the efficiency of clinical diagnosis.●METHODS:Totally 203 infrared meibomian images from 138 patients with dry eye disease,accompanied by corresponding annotations,were gathered for the study.A rectified scribble-supervised gland segmentation(RSSGS)model,incorporating temporal ensemble prediction,uncertainty estimation,and a transformation equivariance constraint,was introduced to address constraints imposed by limited supervision information inherent in scribble *** viability and efficacy of the proposed model were assessed based on accuracy,intersection over union(IoU),and dice coefficient.●RESULTS:Using manual labels as the gold standard,RSSGS demonstrated outcomes with an accuracy of 93.54%,a dice coefficient of 78.02%,and an IoU of 64.18%.Notably,these performance metrics exceed the current weakly supervised state-of-the-art methods by 0.76%,2.06%,and 2.69%,***,despite achieving a substantial 80%reduction in annotation costs,it only lags behind fully annotated methods by 0.72%,1.51%,and 2.04%.●CONCLUSION:An innovative automatic segmentation model is developed for MGs in infrared eyelid images,using scribble annotation for *** model maintains an exceptionally high level of segmentation accuracy while substantially reducing training *** holds substantial utility for calculating clinical parameters,thereby greatly enhancing the diagnostic efficiency of ophthalmologists in evaluating meibomian gland dysfunction.

关键词： infrared meibomian glands images meibomian gland dysfunction meibomian glands segmentation weak supervision scribbled annotation

Interfacial Oxygen Octahedral Coupling-Driven Robust Ferroelectricity in Epitaxial Na_(0.5)Bi_(0.5)TiO_(3)Thin Films

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Research 2024年第2期2023卷 149-157页

作者： Haojie Han Qinghua Zhang Wei Li Yiqun Liu Jiasheng guo Yue Wang Qian Li lin Gu Ce-Wen Nan jing Ma State Key Laboratory of New Ceramics and Fine Processing Schoolof Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

The oxygen octahedral rotation(OOR)forms fundamental atomic distortions and symmetries in perovskite oxides and definitely determines their properties and ***,epitaxial strain and interfacial structural coupling engineering have been developed to modulate the OOR patterns and explore novel properties,but it is difficult to distinguish the 2 ***,different symmetries are induced in Na_(0.5)Bi_(0.5)TiO_(3)(NBT)epitaxial films by interfacial oxygen octahedral coupling rather than epitaxial *** NBT film grown on the Nb:SrTiO_(3)substrate exhibits a paraelectric tetragonal phase,while with La_(0.5)Sr_(0.5)MnO_(3)as a buffer layer,a monoclinic phase and robust ferroelectricity are obtained,with a remanent polarization of 42μC cm^(-2)and a breakdown strength of 7.89 MV cm^(-1),which are the highest record among NBT-based ***,the interfacial oxygen octahedral coupling effect is demonstrated to propagate to the entire thickness of the film,suggesting an intriguing long-range *** work provides a deep insight into understanding the structure modulation in perovskite heterostructures and an important avenue for achieving unique functionalities.

关键词： effect. interfacial coupling