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Acta Mathematicae Applicatae Sinica 2024年

作者： shi-lin mi Guang-zhi DU Yao RONG Li-yun ZUO School of Mathematics and Statistics Shandong Normal University College of Engineering Physics Shenzhen Technology University School of Mathematical Sciences University of Jinan

This paper mainly presents and studies some local and parallel finite element methods for the unsteady magnetohydrodynamic equations with low electromagnetic Reynolds number. Firstly, both the semi discrete and fully discrete local algorithms are provided and investigated, and the theoretical tool crucial to the analysis of the fully discrete local algorithm is obtained. Subsequently, we generalize the fully discrete local algorithm to the fully discrete parallel algorithm. At the end, some numerical experiments are provided to validate the effectiveness and efficiency of our algorithms.

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Reduction behavior of iron ore powder by high-volatile coal in thermogravimetric-gas chromatographic and kinetic analysis

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Journal of Iron and Steel Research International 2024年第1期31卷 92-107页

作者： Rui-meng shi Qi-yuan mi Bin Li Xiao shi Chong Zou Jing Guo Han-jie Guo School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina China International Engineering Consulting Corporation Beijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The reduction behavior of iron ore powder by high-volatile coal was investigated,and its kinetic mechanism was *** effect of volatiles in coal on the reduction reaction of iron ore was compared by utilizing a Xinjiang lignite with a high volatile content and its pyrolysis carbon produced by high-temperature pyrolysis to remove volatiles,serving as a *** mass loss and gas composition of the samples during the reduction process were detected using thermo-gravimetric analysis and gas chromatography,and the morphological changes of iron ore powder were observed through scanning electron *** kinetic parameters of the iron oxide reduction reaction were calculated by the Flynn-Ozawa-Wall method,and the kinetic mechanism of volatile participation in the iron oxide reduction reaction was determined through the Coats-Redfern *** results indicate that the coupling effect between the high-volatile coal pyrolysis and reduction reactions occurs during the second stage of the entire coupling process,which corresponds to the late stage of coal pyrolysis with a substantial release of H_(2)and *** volatiles in coal actively participated in the reduction reaction,reducing the initiation temperature of the reaction by around 200℃.The reduction of iron oxides by high-volatile coal was jointly promoted by the"hydrogen cycle"and"carbon cycle",resulting in a higher reduction extent and metallization rate at the end of the *** high-volatile coal was used as the reductant,the average activation energy for the entire process was 76.5 kJ/mol,a significant decrease compared to the employment of pyrolysis carbon without volatiles as the reductant(1167 kJ/mol).

关键词： Direct reduction High-volatile coal Volatile Kinetics Reduction mechanism

Pulmonary embolism secondary to acute anterior ST-elevation myocardial infarction:a case report

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World Journal of Emergency Medicine 2024年第2期15卷 139-141页

作者： lin Yuan Hong Li Yuhong mi Ying Liang Emergency Critical Center Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China

Thrombophilia denotes a condition,whether acquired or hereditary,characterized by increased susceptibility to hypercoagulation.[1]This condition was first described in 1965,coinciding with the discovery of an inherited predisposition to venous thromboembolism(VTE)in patients deficient in antithrombin III.[2]While arterial and venous thromboses are common in hospitalized patients,acute myocardial infarction(Ami)and pulmonary embolism(PE)stand out as ***,theoccurrenceof Ami complicated by PE is exceedingly rare,especially when considering cases where paradoxical embolism originating from a patent foramen ovale is *** report presents a case of Ami complicated with PE.A comprehensive understanding of the pathophysiology of this rare yet critical condition is important for ensuring prompt diagnosis and treatment.

关键词： embolism infarction acute

High-resolution remote thermometry based on Bi^(3+)-doped 0D zinc halide hybrids

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Science China Chemistry 2024年第8期67卷 2599-2605页

作者： Cui-mi shi Shu-Hua Xue Jin-Yun Wang Liang-Jin Xu Zhong-Ning Chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science Technology Innovation Laboratory for Optoelectronic Information of ChinaFuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Developing highly sensitive optical thermometers is of great significance due to their capability to enable remote and non-contact temperature measurements, rendering them highly applicable in diverse and harsh environments. Herein we report a temperature-dependent phosphor of 0D metal halide hybrid by incorporating Bi^(3+)into the(MePPh_(3))_(2)ZnCl_(4) matrix. Through Bi^(3+)doping,the initially non-luminescent(MePPh_(3))_(2) ZnCl_(4) matrix exhibits a deep-blue emission centered at 453 nm, with a photoluminescence quantum yield(PLQY) of 5.71% and a Stokes shift of 75 nm at room temperature. Experimental characterization demonstrates that exciton-like luminescence of Bi^(3+)is mainly responsible for the blue emission. Single crystals of Bi^(3+)-doped(MePPh_(3))_(2)ZnCl_(4) show an unusual correlation between photoluminescence(PL) lifetime and temperature. Particularly, the dependence of luminescence lifetime on temperature is most remarkable in the temperature range of 80 to 100 K with an exceptional sensitivity up to 0.09 K^(-1), representing one of the best levels for thermometry based on PL decay lifetime. Our work not only provides a viable strategy for designing a novel, environmentally friendly, and stable blue emitter, but also paves the way for precise thermometric application at low temperature.

关键词： lead-free hybrids Bi^(3+)doping blue emission temperature sensing

Establishment and validation of an adherence prediction system for lifestyle interventions in non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2024年第10期30卷 1393-1404页

作者： ming-Hui Zeng Qi-Yu shi Liang Xu Yu-Qiang mi Clinical School of the Second People’s Hospital Tianjin Medical UniversityTianjin 300192China Department of Gastroenterology Cangzhou People’s HospitalCangzhou 061000Hebei ProvinceChina Department of Hepatology Tianjin Second People’s HospitalTianjin 300192China Tianjin Research Institute of Liver Diseases Tianjin 300192China

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease worldwide,affecting about 1/4th of the global population and causing a huge global economic *** date,no drugs have been approved for the treatment of NAFLD,making the correction of unhealthy lifestyles the principle method of *** patients with poor adherence to lifestyle correction and attempting to improve their adherence are therefore very *** To develop and validate a scale that can rapidly assess the adherence of patients with NAFLD to lifestyle *** The Exercise and Diet Adherence Scale(EDAS)was designed based on com-pilation using the Delphi method,and its reliability was subsequently *** and laboratory indicators were measured,and patients completed the EDAS questionnaire at baseline and after 6 *** efficacy of the EDAS was evaluated in the initial ***,the efficacy of the EDAS was internally verified in a validation *** The EDAS consisted of 33 items in six dimensions,with a total of 165 *** EDAS score correlated significantly with daily number of exercise and daily reduction in calorie intake(P500 kacl/d),(sensitivity/specificity was 100.0%/75.8%),while patients score below 97 could nearly rule out the possibility of daily exercise(sensitivity/specificity was 89.5%/44.4%).Total EDAS scores≥116,97-115,andlinical application in this population.

关键词： Fatty liver Lifestyle intervention Behavioral change Patient adherence Compliance

Lateral root elongation in maize is related to auxin synthesis and transportation mediated by N metabolism under a mixed NO_(3)^(–) and NH_(4)^(+) supply

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Journal of Integrative Agriculture 2024年第3期23卷 1048-1060页

作者： Peng Wang Lan Yang Xichao Sun Wenjun shi Rui Dong Yuanhua Wu Guohua mi Key Laboratory of Tobacco Biology and Processing of ministry of Agriculture and Rural Affairs Tobacco Research InstituteChineseAcademy of Agricultural SciencesQingdao 266101China Department of Plant Nutrition College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China College of Resources Hunan Agricultural UniversityChangsha 410128China Agro-Environmental Protection Institute Ministry of Agriculture and Rural AffairsTianjin 300191China

A mixed nitrate (NO_(3)^(–)) and ammonium (NH_(4)^(+)) supply can promote root growth in maize (Zea mays),however,the changes in root morphology and the related physiological mechanism under different N forms are still ***,maize seedlings were grown hydroponically with three N supplied in three different forms (NO_(3)^(–)only,75/25 NO_(3)^(–)/NH_(4)^(+)and NH_(4)^(+)only).Compared with sole NO_(3)^(–)or NH_(4)^(+),the mixed N supply increased the total root length of maize but did not affect the number of axial *** main reason was the increased total lateral root length,while the average lateral root (LR) length in each axle was only slightly *** addition,the average LR density of 2nd whorl crown root under mixed N was also *** with sole nitrate,mixed N could improve the N metabolism of roots (such as the N influx rate,nitrate reductase (NR) and glutamine synthase (GS)enzyme activities and total amino content of the roots).Experiments with exogenously added NR and GS inhibitors suggested that the increase in the average LR length under mixed N was related to the process of N assimilation,and whether the NR mediated NO synthesis participates in this process needs further ***,an investigation of the changes in root-shoot ratio and carbon (C) concentration showed that C transportation from shoots to roots may not be the key factor in mediating lateral root elongation,and the changes in the sugar concentration in roots further proved this ***,the synthesis and transportation of auxin in axial roots may play a key role in lateral root elongation,in which the expression of ZmPIN1B and ZmPIN9 may be involved in this *** study preliminarily clarified the changes in root morphology and explored the possible physiological mechanism under a mixed N supply in maize,which may provide some theoretical basis for the cultivation of crop varieties with high N efficiency.

关键词： maize NO_(3)^(–)/NH_(4)^(+)ratio lateral root elongation N assimilation indole-3-acetic acid

On the Innovation,Design,Construction,and Experiments of OMEGA-Based SSPS Prototype:The Sun-Chasing Project

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Engineering 2024年第5期36卷 90-101页

作者： Baoyan Duan Yiqun Zhang Guangda Chen Ze Zhao Jianwei mi Xun Li lin Yang Xi Li Research Institute on Mechatronics Xidian UniversityXi’an 710071China Research Institute of Antenna Xidian UniversityXi’an 710071China

This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 innovation design was ***,field-coupling theoretical models of sunlight concentration,photoelectric conversion,and transmitting antennas were established,and a systematic optimization design method was ***,a beam waveform optimization methodology considering both a high beam collection efficiency and a circular stepped beam shape was ***,a control strategy was developed to control the condenser pointing toward the sun while maintaining the transmitting antenna toward the ***,a high-efficiency heat radiator design method based on bionics and topology optimization was ***,a method for improving the rectenna array’s reception,rectification,and direct current(DC)power synthesis efficiencies is ***,high-precision measurement technology for high-accuracy beam-pointing control was ***,a smart mechanical structure was designed and ***,the developed SSPS ground demonstration and verification system has the capacity for sun tracking,a high concentration ratio,photoelectric conversion,microwave conversion and emission,microwave reception,and rectification,and thus satisfactory results were obtained.

关键词： OMEGA-SSPS Full-link and full-system Beam collection efficiency Circular stepped beam shape Smart structure Field coupling theoretical model `Beam pointing control

Carbon Emission Factors Prediction of Power Grid by Using Graph Attention Network

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Energy Engineering 2024年第7期121卷 1945-1961页

作者： Xin Shen Jiahao Li YujunYin Jianlin Tang Weibin lin mi Zhou Measurement Center Yunnan Power Grid Co.Ltd.Kunming650000China Electric Power Research Institute China Southern Power Grid Co.Ltd.Guangzhou510530China Guangdong Provincial Key Laboratory of Intelligent Measurement and Advanced Metering of Power Grid Guangzhou510530China

Advanced carbon emission factors of a power grid can provide users with effective carbon reduction advice,which is of immense importance in mobilizing the entire society to reduce carbon *** method of calculating node carbon emission factors based on the carbon emissions flow theory requires real-time parameters of a power ***,it cannot provide carbon factor information *** address this issue,a prediction model based on the graph attention network is *** model uses a graph structure that is suitable for the topology of the power grid and designs a supervised network using the loads of the grid nodes and the corresponding carbon factor *** network extracts features and transmits information more suitable for the power system and can flexibly adjust the equivalent topology,thereby increasing the diversity of the *** input and output data are simple,without the power grid *** demonstrated its effect by testing IEEE-39 bus and IEEE-118 bus systems with average error rates of 2.46%and 2.51%.

关键词： Predict carbon factors graph attention network prediction algorithm power grid operating parameters

A novel Tb^(3+) and Eu^(3+) co-doped dual-emitting phosphate K_(3)SrBi(P_(2)O_(7))_(2) phosphor for application in FIR thermometers

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Journal of Rare Earths 2024年第3期42卷 455-463,I0001页

作者： Baochen Wang shifeng Sun Zeqi Li Zongwang Li Weiwei lin Chao Zeng Yan-gai Liu Ruiyu mi School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu241000China State-Province Joint Engineering Laboratory of Zeolite Membrane Materials Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationInstitute of Advanced MaterialsCollege of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China Beijing Key Laboratory of Materials Utilization of Nonmetallic minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing100083China

Rare earth co-doped phosphor for fluorescence intensity ratio(FIR) thermometer has gained increasing attention in recent years. Herein, the novel Tb^(3+)and Eu^(3+)co-doped K_(3)SrBi(P_(2)O_(7))_(2)(KSBP) phosphate phosphors were reported. The crystal structure of the title phosphor was determined using Rietveld refinement and proved to have a three-dimensional structure. The time-resolved spectroscopy reveals that there is almost no energy transfer between Tb^(3+)and Eu^(3+). More importantly, Tb^(3+)and Eu^(3+)emissions show different thermal quenching behaviors, which claims the potential of this material for application in optical thermometer. The FIR of the typical KSBP:0.02Tb^(3+),0.04Eu^(3+)sample demonstrates a polynomial relationship as a function of temperature and the absolute and relative sensitivity are0.025 K^(-1) and 0.59%/K, respectively. In general, our study reports a novel and potential KSBP:Tb^(3+),Eu^(3+)phosphate phosphor that is promising for use in high-sensitive FIR thermometers.

关键词： Phosphor Thermometer Fluorescence intensity ratio Thermal stability Rare earths

Fault DiagnosisMethod of Energy Storage Unit of Circuit Breakers Based on EWT-ISSA-BP

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Energy Engineering 2024年第7期121卷 1991-2007页

作者： Tengfei Li Wenhui Zhang Ke mi Qingming lin Shuangwei Zhao Jiayi Song Puneng Electric Power Technology Engineering Branch Shanghai Hengnengtai Enterprise Management Co.Ltd.Shanghai200437China School of Electrical Engineering Sichuan UniversityChengdu610065China

Aiming at the problem of energy storage unit failure in the spring operating mechanism of low voltage circuit breakers(LVCBs).A fault diagnosis algorithm based on an improved Sparrow Search Algorithm(ISSA)optimized Backpropagation Neural Network(BPNN)is proposed to improve the operational safety of *** the 1.5kV/4000A/75kA LVCB as an *** to the current operating characteristics of the energy storage motor,fault characteristics are extracted based on Empirical Wavelet Transform(EWT).Traditional BPNN has problems such as difficulty adjusting network weights and thresholds,being sensitive to initial weights,and quickly falling into local optimal *** Sparrow Search Algorithm(SSA)with self-adjusting weight factors combined with bidirectional mutations is added to optimize the selection of BPNN *** results show that the ISSA-BPNN can accurately and quickly distinguish six conditions of motor voltage reduction:motor voltage increase,motor voltage decrease,energy storage spring stuck,transmission gear stuck,regular state and energy storage spring not *** is suitable for fault diagnosis and detection of the energy storage part of LVCB.

关键词： Low voltage circuit breakers energy storage motor current sparrow search algorithm empirical wavelet transform fault diagnosis