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Effect of BaO and MgO on structure and properties of aluminate slag with various CaO/Al_(2)0_(3)ratios

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Journal of Iron and Steel Research International 2024年第1期31卷 204-214页

作者： Yu-qi Kong Ting Wu wen-zhi Xia wen Yang Hai-chuan Wang School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina Key laboratory of Metallurgical Emission Reduction and Resource Recycling(Ministry of Education) Anhui University of TechnologyMa’anshan243002AnhuiChina

To provide theoretical guidance for performance stability control of low-reactive mold fluxes,the effects of BaO and MgO on the structure and properties of aluminate slag with various CaO/Al_(2)0_(3)(C/A)ratios were investigated using the Fourier transform infrared spectrometer,Raman spectroscope,hemispherical melting point instrument,rotational viscometer and X-ray *** results indicated that with BaO and MgO addition,the structure polymerization was first weakened and then enhanced at C/A of 1.1,and the transition contents corresponded to 8 wt.%BaO and 2 wt.%MgO,respectively,while the structure polymerization decreased continuously at C/A of *** the viscosity change was well consistent with the structure evolution,the polymerization degree played a more prominent role in the slag viscosity than superheat degree when the melting temperature difference was within 40℃.The break temperature decreased initially and then increased with augment of BaO and MgO at C/A of 1.1,while it manifested a decrease trend with BaO addition,and it decreased obviously but then turned to increase with MgO increment at C/A of *** crystallization phase and crystallization ratio kept stable with BaO increment,while the crystallization ratio rose greatly with MgO promoting liAlO_(2)precipitation at C/A of *** crystal types of all experimental slags were mainly Ca_(12)Al_(14)O_(33)and CaF_(2)at C/A of 1.3,and the precipitation of crystalline phase BaAl2O4 demonstrated a rising trend,while that of Ca_(12)Al_(14)O_(33)gradually declined with BaO augment.

关键词： Aluminate slag Structure MgO BaO Viscosity Property

Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： wen-Jing Zhao Jing Wang Zhong-Yang qi Hui-qing liu National Key laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before inject

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient

Time-inconsistent stochastic linear-quadratic control problem with indefinite control weight costs

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Science China Mathematics 2024年第1期67卷 211-236页

作者： qi lü Bowen Ma School of Mathematics Sichuan UniversityChengdu 610064China

A time-inconsistent linear-quadratic optimal control problem for stochastic differential equations is *** introduce conditions where the control cost weighting matrix is possibly *** such conditions,we obtain a family of closed-loop equilibrium strategies via multi-person differential *** result extends Yong’s work(2017) in the case of stochastic differential equations,where a unique closed-loop equilibrium strategy can be derived under standard conditions(namely,the control cost weighting matrix is uniformly positive definite,and the other weighting coefficients are positive semidefinite).

关键词： linear-quadratic optimal control problem time-inconsistent cost functional generalized Riccati equation indefinite control weight cost closed-loop equilibrium strategy

Rheological Behaviors of Polymers with Nanoparticles Tethered at Each End

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Chinese Journal of Polymer Science 2024年第3期42卷 400-406,I0009页

作者： Song-qi Zhang wen-qing Wang Jia-Ping lin li-Quan Wang Shanghai Key laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from-1/2 to-3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology.

关键词： Polymer rheology Modulus Viscosity Molecular dynamics

Diagnostic value associated with the combination of saliva pepsin and microorganisms in functional heartburn and gastroesophageal reflux disease

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World Journal of Gastroenterology 2024年第19期30卷 2612-2614页

作者： Yu-qi Huang Chao Yang wen luo Department of Stomatology The First Affiliated Hospital of Hainan Medical UniversityHaikou 570102Hainan ProvinceChina School of Stomatology Hainan Medical UniversityHaikou 571199Hainan ProvinceChina Research and Development Department Shenzhen Uni-medica Technology Co.LtdShenzhen 518051Guangdong ProvinceChina Department of Stomatology The People’s Hospital of LonghuaShenzhen 518109Guangdong ProvinceChina

Heartburn is a common symptom shared by both gastroesophageal reflux disease(GERD)and functional heartburn(FHB),which can make it challenging to differentiate between the two ***,examining oral manifestations of GERD can be a cost-effective and readily available method to aid in this differentiation *** may serve as a valuable tool in distinguishing GERD from FHB.

关键词： Gastroesophageal reflux disease Gastric acid Heartburn Differential diagnosis Epidemiology Oral manifestations Prevalence Risk factors Dental erosion Periodontal diseases

Correlation analysis of interstitial maturity and prognosis of colorectal cancer:Meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2816-2825页

作者： Zhen-Jun liu Xu-wen Zhang qi-qi liu Shao-Zhao Wang Department of Gastrointestinal Surgery Feicheng People's HospitalFeicheng 271600Shandong ProvinceChina Department of Hepatobiliary Surgery Feicheng People's HospitalFeicheng 271600Shandong ProvinceChina Department of Gastrointestinal Surgery Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina Department of Anorectal Word Central Hospital Affiliated Shandong First Medical UniversityJinan 250013Shandong ProvinceChina

BACKGROUND To investigate the relationship between interstitial maturity and prognosis of colorectal *** To examine the correlation between interstitial maturity and the prognosis of colorectal *** The paper database PubMed,EMBASE,Cochranelibrary,Springerlink,CNKI,and Wanfang database were searched until December 2023."tumor stroma maturity""desmoplastic stroma reaction""desmoplastic reaction""stroma reaction""degree of stroma reaction""stroma classification""stroma density""colorectal cancer""colon cancer""rectal cancer""prognosis"were searched for the search *** system assessors independently screened the literature quality according to the inclusion exclusion criteria,Quality evaluation and data extraction were performed for the included literatures,and meta-analysis was performed for randomized control trials included at using Review Manager 5.2 *** Finally,data of 9849 patients with colorectal cancer from 19 cosets in 15 literatures were included,including 4339 patients with mature type(control group),3048 patients with intermediate type(intermediate group)and 2456 patients with immature type(immature group).The results of meta-analysis showed:Relapse-free survival[hazard ratio(HR)=2.66,95%confidence interval(CI):2.30-3.08;Pl(HR=3.68,95%CI:2.33-5.81;Pll survival(HR=1.70,95%CI:1.53-1.87;Ply lower than those in mature group(control group);relapse-free survival(HR=1.36,95%CI:1.17-1.59;Pl rate(HR=1.85,95%CI:1.53-2.24;Ply lower than the mature group(control group).CONClUSION There is the correlation between tumor interstitial maturity and survival prognosis of colorectal cancer,and different degrees of tumor interstitial maturity have a certain impact on the quality of life of colorectal cancer patients.

关键词： Colorectal tumor Survival prognosis Tumor interstitial maturity Systematic review Meta-analysis

Enhancement of comprehensive properties of Nb-Si based in-situ composites by Ho rare earth doping

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Rare Metals 2024年第9期43卷 4508-4520页

作者： Wei Wei qi Wang Rui-Run Chen Chao-wen Zheng Yan-qing Su National Key laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

This study examines the microstructure,mechanical properties(with a focus on room-temperature toughness),and oxidation resistance of Ho-doped NbDSi based in-situ *** base alloy consists of the coarse primary Nb_(5)Si_(3)phase and the Nb_(5)Si_(3)+Nbss(Nb solid solution)eutectic *** doping influences the solidification *** the Ho doping is higher than0.2 at%,the alloys transform into eutectic *** can be solid-solved in trace amounts in the Nbss ***,most of Ho forms a stable Ho oxide phase,which alleviates oxygen contamination problem to some ***,the interface separation between Ho oxide and other phases reduces the plastic deformation ***,with 0.4 at%Ho doping,the K_(Q)value is18.03 MPa·m^(1/2),which is 31.1%higher than that of the base *** strength of the Ho-doped alloys does not deteriorate with an increase in ***,the large network-like Ho_(2)O_(3)in the 0.8Ho alloy causes a decrease in toughness and *** addition,the Ho oxide phase effectively blocks the inward oxygen *** 0.8 at%Ho doping,the oxidation mass gain per unit area is 10.16 mg·cm^(2),which is 39.7%lower than that of the base alloy.

关键词： Nb-Si based composites Rare earth elements Ho Microstructure Properties

Transforming Adolescent Smiles:Correcting Skeletal Mandibular Retrusion and Bimaxillary Protrusion with Clear Aligners

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Current Medical Science 2024年第3期44卷 657-666页

作者： wen-jie FAN Jia-qi ZHANG Jia-qi ZHAN li HU li-li CHEN Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China School of Stomatology Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Wuhan National High Magnetic Field Center Wuhan430074China The Affiliated lianyungang Hospital of Xuzhou Medical University/The First People’s Hospital of lianyungang Lianyungang222000China The First Affiliated Hospital of Kangda College of Nanjing Medical University/The First People’s Hospital of lianyungang Lianyungang222000China

Maxillary protrusion combined with mandibular retraction is a highly prevalent but extremely complex maxillofacial deformity that can have a serious negative impact on patients’facial aesthetics and mental *** traditional orthodontic treatment strategy often involves extracting 4 first premolars and conventional fixed techniques,combined with mini-implant screws,to retract the anterior teeth and improve facial *** recent years,an invisible orthodontic technique,without brackets,has become increasingly ***,while an invisible aligner has been used in some cases with reasonable results,there remain significant challenges in achieving a perfect *** case report presents an adolescent patient with bimaxillary protrusion and mandibular *** on the characteristics of the invisible aligners and the growth characteristics of the adolescent’s teeth and jawbone,we designed precise three-dimensional tooth movement and corresponding resistance/over-correction for each tooth,while utilizing the patient’s jawbone growth potential to promote rapid development of the mandible,accurately and efficiently correcting bimaxillary protrusion and skeletal mandibular *** patient’s facial aesthetics,especially the lateral morphology,have been greatly improved,and various aesthetic indicators have also shown significant changes,and to the patient’s great benefit,invasive mini-implant screws were not used during the *** case highlights the advantages of using invisible aligners in adolescent maxillary protrusion combined with mandibular retraction ***,comprehensive and accurate design combined with good application of growth potential can also enable invisible orthodontic technology to achieve perfect treatment effects in tooth extractions,providing clinical guidance for orthodontists.

关键词： mandibular retrusion esthetic orthodontic treatment clear aligners growth potential

Exploring deep learning for landslide mapping:A comprehensive review

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China Geology 2024年第2期7卷 330-350页

作者： Zhi-qiang Yang wen-wen qi Chong Xu Xiao-yi Shao College of Surveying and Geo-Informatics Tongji UniversityShanghai 200092China National Institute of Natural Hazards Ministry of Emergency ManagementBeijing 100085China Key laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing 100085China

A detailed and accurate inventory map of landslides is crucial for quantitative hazard assessment and land *** methods relying on change detection and object-oriented approaches have been criticized for their dependence on expert knowledge and subjective *** advancements in highresolution satellite imagery,coupled with the rapid development of artificial intelligence,particularly datadriven deep learning algorithms(Dl)such as convolutional neural networks(CNN),have provided rich feature indicators for landslide mapping,overcoming previous *** this review paper,77representative Dl-based landslide detection methods applied in various environments over the past seven years were *** study analyzed the structures of different Dl networks,discussed five main application scenarios,and assessed both the advancements and limitations of Dl in geological hazard *** results indicated that the increasing number of articles per year reflects growing interest in landslide mapping by artificial intelligence,with U-Net-based structures gaining prominence due to their flexibility in feature extraction and ***,we explored the hindrances of Dl in landslide hazard research based on the above research *** such as black-box operations and sample dependence persist,warranting further theoretical research and future application of Dl in landslide detection.

关键词： landslide Mapping Quantitative hazard assessment Deep learning Artificial intelligence Neural network Big data Geological hazard survery engineering