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Crystallization of RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family of layered hydroxides(RE=Gd-Lu lanthanides and Y),derivation of RE_(2)O_(2)SO_(4),photoluminescence and optical thermometry

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Journal of Rare Earths 2024年第8期42卷 1496-1506,I0003页

作者： Fan li Zhenqi Song Zhiyuan Pan Sihan Feng Qi Zhu Ji-guang li Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Research Center for Functional Materials National Institute for Materials ScienceTSsukuboaIbaraki3050044Japan

Layered rare-earth hydroxides(LREHs) draw wide research interest because of their peculiar crystal structure,rich interlayer chemistry and abundant functionality of the RE element,but are limited to the two categories of RE_(2)(OH)_(5)A·nH_(2)O(A:typical of Cl^(-)or NO_(3)^(-)) and RE_(2)(OH)_(4)SO_(4)·nH_(2)*** the other hand,rare-earth oxysulfates(RE_(2)O_(2)SO_(4)) have attracted attention due to their properties of large-capacity oxygen storage,low-temperature magnetism and luminescence,but their preparation procedure mostly involves toxic SO_(x) gases and/or complicated *** this work,RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family of LREHs(RE=Gd-Lu lanthanides and Y) were produced via hydrothermal reaction,from which phase-pure RE_(2)O_(2)SO_(4) was derived via subsequent annealing at 800℃ in air without the involvement of SO_(x),The compounds were thoroughly characterized to reveal the intrinsic influence of lanthanide contraction(RE^(3+) radius) on crystal structure,thermal behavior(dehydroxylation/decarbonation/desulfurization),vibrational property and crystallite *** analyzing the photoluminescence of Eu^(3+) and Sm^(3+)in the Gd_(2)O_(2)SO_(4) typical host it is found that the 617 nm(Eu^(3+),λ_(ex)=275 nm) and 608 nm(Sm^(3+),λ_(ex)=407 nm) main emissions can retain as high as ^(7)9.6% and 85.5%of their room-temperature intensities at 423 K,with activation energies of ~0.19 and 0.21 eV for thermal quenching,*** also indicates that both the phosphors have the potential for optical temperature sensing via the fluorescence intensity ratio(FIR) technology,whose maximum relative sensitivity reaches -2.70%/K for Eu^(3+)and 1.73%/K for Sm^(3+) at 298 K.

关键词： Layered hydroxide RE_(2)O_(2)SO_(4) Luminescence Optical temperature sensing Rare earths

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Ultrahigh thermoelectric properties of p‐type Bi_(x)Sb_(2−x)Te_(3)thin films with exceptional flexibility for wearable energy harvesting

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Carbon Energy 2024年第8期6卷 273-284页

作者： Zhuang‐Hao Zheng Yi‐ming Zhong Yi‐liu li Mohammad Nisar Adil Mansoor Fu li Shuo Chen guang‐Xing liang Ping Fan Dongyan Xu Meng Wei Yue‐Xing Chen Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina Department of Mechanical and Automation Engineering The Chinese University of Hong KongSha TinChina

Use of a flexible thermoelectric source is a feasible approach to realizing selfpowered wearable electronics and the Internet of *** thin films are promising candidates for fabricating flexible power supply,but obtaining highthermoelectric‐performance thin films remains a big *** the present work,a p‐type Bi_(x)Sb_(2−x)Te_(3)thin film is designed with a high figure of merit of 1.11 at 393 K and exceptional flexibility(less than 5%increase in resistance after 1000 cycles of bending at a radius of∼5 mm).The favorable comprehensive performance of the Bi_(x)Sb_(2−x)Te_(3)flexible thin film is due to its excellent crystallinity,optimized carrier concentration,and low elastic modulus,which have been verified by experiments and theoretical ***,a flexible device is fabricated using the prepared p‐type Bi_(x)Sb_(2−x)Te_(3)and n‐type Ag_(2)Se thin ***,an outstanding power density of∼1028μWcm^(−2)is achieved at a temperature difference of 25 *** work extends a novel concept to the fabrication of highperformance flexible thin films and devices for wearable energy harvesting.

关键词： Bi_(x)Sb_(2−x)Te_(3) electrical transport properties flexibility thermoelectric

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Complete kinetic model for esterification reaction of lauric acid with glycerol to synthesize glycerol monolaurate

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Chinese Journal of Chemical Engineering 2024年第6期70卷 211-221页

作者： Han-Qiao Hu Yue Zhang ming Fan Yong Cai guang-Wen Chu liang-liang Zhang Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Petrochemical Research Institute China National Petroleum CorporationBeijing 102206China

Glycerol monolaurate(GML)is a widely used industrial chemical with excellent emulsification and antibacterial *** direct esterification of glycerol with lauric acid is the main method to synthesize *** this work,the kinetic process of direct esterification was systematically studied using p-toluenesulfonic acid as catalyst.A complete kinetic model of consecutive esterification reaction has been established,and the kinetic equation of acid catalysis was *** isomerization reactions of GML and glycerol dilaurate were *** was found that the reaction was an equilibrium reaction and the reaction rate was faster than the esterification *** kinetic equations of the consecutive esterification reaction were obtained by experiments as k_(1)=(276+92261Xcat)exp(-37720/RT)and k_(2)=(80+4413Xcat)exp(-32240/RT).The kinetic results are beneficial to the optimization of operating conditions and reactor design in GML production process.

关键词： Glycerol monolaurate p-Toluenesulfonic acid Esterification Kinetics Mass transfer

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基于人工蜂群算法的混沌信号盲提取

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物理学报 2016年第23期65卷 44-51页

作者：李广明胡志辉东莞理工学院计算机学院东莞523808 华南理工大学电子与信息学院广州510641

针对混沌信号在噪声信号中的提取问题,本文将其建立于线性混合模型进行分析.在该模型下,提出一种结合高维核函数的性能函数,该函数的计算复杂度较低.在使用人工蜂群算法来处理该多峰函数优化问题时,文中采用马尔可夫模型分析了人工蜂群... 详细信息

针对混沌信号在噪声信号中的提取问题,本文将其建立于线性混合模型进行分析.在该模型下,提出一种结合高维核函数的性能函数,该函数的计算复杂度较低.在使用人工蜂群算法来处理该多峰函数优化问题时,文中采用马尔可夫模型分析了人工蜂群算法的有效性.仿真实验表明本文方法能在较低复杂度下提取出相关系数很高的估计信号.

关键词：混沌信号盲提取核函数人工蜂群算法

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Effect of MgO-Cr_(2)O_(3) and Mg0-MgAl_(2)0_(4)-based refractories on refractory-steel interface reaction and cleanliness of pipeline steel

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Journal of Iron and Steel Research International 2024年第4期31卷 849-860页

作者： guang-mei Yang Cheng Yuan Chang liu Qiang Wang guang-qiang li Yong-shun Zou Ao Huang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The interaction of MgO-MgAl_(2)O_(4)-based and MgO-Cr_(2)O_(3)-based refractories with X70 molten steel was studied by immersion experiments at 1560℃.The effects of immersion time(30 and 60 min)on the contents of total oxygen(TO),Al,Nb,Si,Mn,and Cr as well as the composition,number density,and size distribution of inclusions in the molten steel were *** influence of the penetration and erosion degree of the molten steel to the refractory on the steel-refractory interface layer was *** results show that,at 1560℃,the MgO-MgAl_(2)O_(4)-based refractory can better control the contents of TO and the composition of molten steel compared with the MgO-Cr_(2)O_(3)-based *** TO content is only 16×10^(-4) wt.%in the molten steel after reacted with the Mg0-MgAl_(2)O_(4)-based refractory at the end point of refining,4 accounting for 11.5%of that reacted with the MgO-Cr_(2)O_(3)-based refractory(139×10^(-4) wt.%).The number density of inclusions is only 14 mm^(-2),and the average size ofinclusions is only 1.31μm,with thelargest proportion of inclusions in 1-2μm(70%).The Al_(2)O_(3)-MnS-CaO complex inclusions in the original steel changed to complex inclusions dominated by Cr-Nb-Mn-S-O and ***_(2)O_(3),corresponding to the MgO-Cr_(2)O_(3)-based and MgO-MgAl_(2)O_(4)-based refractories,*** ***_(2)O_(3) layer was formed at the reaction interface between MgO-MgAl_(2)O_(4)-based refractory and molten steel,which is helpful to restrict the erosion of refractories and the pollution of molten *** damage mechanism of the MgO-Cr_(2)O_(3)-based refractory is mainly permeation and chemical reaction,while the damage of the MgO-MgAl_(2)O_(4)-based refractory is mainlyscouring erosion.

关键词： MgO-Cr_(2)O_(3)-based refractory MgO-MgAl O_(4)-based refractory Nonmetallic inclusion Erosion interface layer Steel penetration

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Dynamic simulation insights into friction weakening effect on rapid long-runout landslides:A case study of the Yigong landslide in the Tibetan Plateau,China

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China Geology 2024年第2期7卷 222-236页

作者： Zi-zheng Guo Xin-yong Zhou Da Huang Shi-jie Zhai Bi-xia Tian guang-ming li School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China School of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Tianjin Municipal Engineering Design&Research Institute(TMEDI) Tianjin 300392China

This study proposed a novel friction law dependent on velocity,displacement and normal stress for kinematic analysis of runout process of rapid *** well-known Yigong landslide occurring in the Tibetan Plateau of China was employed as the case,and the derived dynamic friction formula was included into the numerical simulation based on Particle Flow *** showed that the friction decreased quickly from 0.64(the peak)to 0.1(the stead value)during the 5s-period after the sliding initiation,which explained the behavior of rapid movement of the *** monitored balls set at different sections of the mass showed similar variation characteritics regarding the velocity,namely evident increase at the initial phase of the movement,followed by a fluctuation phase and then a stopping *** peak velocity was more than 100 m/s and most particles had low velocities at 300s after the landslide *** spreading distance of the landslide was calculated at the two-dimension(profile)and three-dimension scale,*** with the simulation result without considering friction weakening effect,our results indicated a max distance of about 10 km from the initial unstable position,which fit better with the actual situation.

关键词： Rapid long-runout landslide PFC Friction weakening Three-dimension Numerical simulation Tibetan Plateau Hydrogeology Engineering Geological hazards survey engineering

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Endoscopic polidocanol foam sclerobanding for the treatment of grade Ⅱ-Ⅲ internal hemorrhoids:A prospective,multi-center,randomized study

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World Journal of Gastroenterology 2024年第38期30卷 3326-3335页

作者： Chun-Ying Qu Fei-Yu Zhang Yi Zhang ming-ming li Zheng-Hong li Mei-Hong Cai Lei-ming Xu Feng Shen Wen Wang Wu-lian lin Feng-Yu Gao Hao Zhang guang-Yu Chen Department of Gastroenterology&Endoscopy Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Gastroenterology The 900th Hospital of the People’s Liberation Army Joint Service Support ForceFuzhou 350025Fujian ProvinceChina Department of Endoscopy Shandong Provincial Maternal and Child Health Care Hospital Affiliated to Qingdao UniversityJinan 250014Shandong ProvinceChina Department of Endoscopy Baoshan People’s Hospital of Yunnan ProvinceBaoshan 678000Yunnan ProvinceChina Department of Gastroenterology Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China

BACKGROUND Endoscopic rubber band ligation(ERBL)is a nonsurgical technique for the treatment of symptomatic internal hemorrhoids but is limited by recurrence and post-procedural *** To evaluate satisfaction,long-term recurrence,and post-procedural pain in managing internal hemorrhoids using a combination of polidocanol foam sclerotherapy and *** This was a prospective,multicenter,randomized study.A total of 195 consecutive patients diagnosed with grade II-III internal hemorrhoids were enrolled from four tertiary hospitals and randomly divided into a cap-assisted endoscopic polidocanol foam sclerobanding(EFSB)or an ERBL *** patients were followed-up for 12 ***-based severity and post-procedural pain were assessed using a hemorrhoid severity score(HSS)and a visual analog scale(VAS).Continuous variables were reported as medians and interquartile *** One hundred and ninety-five patients were enrolled,with 98 in the EFSB *** was lower in the EFSB group than in the ERBL group at 8 weeks[4.0(3.0-5.0)vs 5.0(4.0-6.0),P=0.003]and 12-month[2.0(1.0-3.0)vs 3.0(2.0-3.0),Plinear regression analysis demonstrated that EFSB treatment[B=-0.915,95%confidence interval(CI):−1.301 to−0.530,P=0.001]and rubber band number(B=0.843,95%CI:0.595-1.092,Plief from the recurrence of prolapse and pain 24 hours post-procedure.

关键词： Internal hemorrhoids Endoscopic therapy Polidocanol foam Sclerotherapy Rubber band ligation Sclerobanding

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Evaluation of left ventricular systolic function in type 2 diabetes mellitus patients with and without peripheral vascular disease

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World Journal of Diabetes 2024年第6期15卷 1280-1290页

作者： guang-An li Jun Huang li Fan Department of Echocardiography The Affiliated Changzhou Second People’s Hospital with Nanjing Medical UniversityChangzhou 213000Jiangsu ProvinceChina

BACKGROUND Peripheral vascular disease(PVD)is a common complication of type 2 diabetes mellitus(T2DM).Patients with T2DM have twice the risk of PVD as nondiabetic *** To evaluate left ventricular(LV)systolic function by layer-specific global longitudinal strain(GLS)and peak strain dispersion(PSD)in T2DM patients with and without *** Sixty-five T2DM patients without PVD,57 T2DM patients with PVD and 63 normal controls were enrolled in the ***-specific GLS[GLS of the epimyocardium(GLSepi),GLS of the middle myocardium(GLSmid)and GLS of the endocardium(GLSendo)]and PSD were *** operating characteristic(ROC)analysis was performed to calculate the sensitivity and specificity of LV systolic dysfunction in T2DM patients with *** calculated Pearson’s correlation coefficients between biochemical data,echocardiographic characteristics,and layer-specific GLS and *** There were significant differences in GLSepi,GLSmid and GLSendo between normal controls,T2DM patients without PVD and T2DM patients with PVD(PT2DM patients without PVD>T2DM patients with PVD in the absolute value of GLS(Plic dysfunction in T2DM patients with *** lipoprotein cholesterol was positively correlated with GLSepi,GLSmid and PSD(Plic dysfunction in T2DM ***-specific GLS and PSD can be used to detect LV systolic dysfunction accurately and conveniently in T2DM patients with or without PVD.

关键词： Type 2 diabetes mellitus Peripheral vascular disease Speckle tracking echocardiography Global longitudinal strain Peak strain dispersion

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Interaction between adolescent sleep rhythms and gender in an obese population

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World Journal of Clinical Cases 2024年第1期12卷 86-94页

作者： Nan-Nan Wu Guo-li Yan Hong-Yu Zhang ling Sun Min Hou guang-ming Xu Department of Laboratory Medicine Tianjin Chest HospitalTianjin 300222China Mental Health Center of Tianjin Medical University Tianjin Anding HospitalTianjin 300222China Department of Child and Adolescent Psychology Mental Health Center of Tianjin Medical UniversityTianjin 300222China

BACKGROUND The obesity rate of adolescents is gradually increasing,which seriously affects their mental health,and sleep plays an important role in adolescent *** To investigate the relationship between sleep rhythm and obesity among adolescents and further explores the interactive effect of sleep rhythm and gender on adolescent obesity,providing a theoretical basis for developing interventions for adolescent *** Research data source Tianjin Mental Health Promotion Program for *** April to June 2022,this study selected 14201 students from 13 middle schools in a certain district of Tianjin as the research subject using the convenient cluster sampling *** these students,13374 accepted and completed the survey,with an effective rate of 94.2%.The demographic data and basic information of adolescents,such as height and weight,were collected through a general situation *** sleep rhythm of adolescents was evaluated using the reduced version of the morningness-eveningness *** A total of 13374 participants(6629 females,accounting for 49.56%;the average age is 15.21±1.433 years)were *** them,the survey showed that 2942 adolescent were obesity,accounting for 22%and 2104 adolescent were overweight,accounting for 15.7%.Among them,1692 male adolescents are obese,with an obesity rate of 25.1%,higher than 18.9%of female *** is a statistically significant difference between the three groups(χ2=231.522,P<0.000).The obesity group has the smallest age(14.94±1.442 years),and there is a statistical difference in age among the three groups(F=69.996,P<0.000).Obesity rates are higher among individuals who are not-only-child,have residential experience within six months,have family economic poverty,and have evening-type sleep(P<0.05).Logistic regression analysis shows a correlation between sleep rhythm and adolescent ***-type sleep rhythm can increase the risk of obesity in male adoles

关键词： Adolescent Obesity Sleep rhythm Gender Interaction

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Scaling laws governing the elastic properties of 3D graphenes

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Science China(Technological Sciences) 2024年第6期67卷 1748-1756页

作者： li ming LU Guo YU HaoDong li MengLei ZHENG FaWei Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE)School of PhysicsBeijing Institute of TechnologyBeijing100081China Beijing Key Lab of Nanophotonics&Ultrafine Optoelectronic Systems School of PhysicsBeijing Institute of TechnologyBeijing100081China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing100088China Department of Physics Capital Normal UniversityBeijing100048China

In this study,we comprehensively investigated the scaling law for elastic properties of three-dimensional honeycomb-like graphenes(3D graphenes)using hybrid neural network potential-based molecular dynamics simulations and theoretical *** elastic constants were obtained as functions of honeycomb hole size,denoted by the graphene wall length *** five independent elastic constants in the large-L limit are proportional to L^(-1).The associated coefficients are combinations of elastic constants of two-dimensional ***-order terms including L^(-2)and L^(-3)emerge for finite L *** have three origins,the distorted areas close to the joint lines of 3D graphenes,the variation in solid angles between graphene plates,and the bending distortion of graphene ***,the chirality becomes essential with decreasing L because the joint line structures are different between the armchair and zigzag-type 3D *** findings provide insights into the elastic properties of graphene-based superstructures and can be used for further studies on graphene-based materials.

关键词： scaling law neural network elastic properties 3D graphene

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