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STUDIES On THE SOLID-STATE PHOTOCHEMICAL RFACTIONS OF ANTIPYRINE WITH AROMATIC ALDEHYDE

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Chinese Chemical Letters 1993年第2期4卷 111-114页

作者： Ji Ben MENG guo Qiang XIONG yong mei WANG Department of Chemistry,Nankai University,Tianjin

Solid state photochemical reactions of antipyrine with 5-formyl-1,3- dimethyluracil,p-nitrobenzaldehyde and p-hydroxybenzaldehyde have been *** structures of 4 hey compounds obtained were determined by IR,UV,\+1HNHR,n... 详细信息

关键词： STUDIES On THE SOLID-STATE PHOTOCHEMICAL RFACTIONS OF ANTIPYRINE WITH AROMATIC ALDEHYDE

On the Strong Approximation for a Simple Reentrant Line in Light Traffic Under First-buffer First-served Service Discipline

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 823-839页

作者： Kai-ming YANG yong-jiang guo School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

For a 2-station and 3-class reentrant line under first-buffer first-served(FBFS)service discipline in light traffic,we firstly construct the strong approximations for performance measures including the queue length,workload,busy time and idle time *** on the obtained strong approximations,we use a strong approximation method to find all the law of the iterated logarithms(LILs)for the above four performance measures,which are expressed as some functions of system parameters:means and variances of interarrival and service times,and characterize the fluctuations around their fluid approximations.

关键词： reentrant line queueing network FBFS service discipline strong approximation LIL Brownian motion

A new monitoring index for ecological vulnerability and its application in the Yellow River Basin,China from 2000 to 2022

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Journal of Arid Land 2024年第9期16卷 1163-1182页

作者： guo Bing XU mei ZHANG Rui LUO Wei School of Civil Engineering and Geomatics Shandong University of TechnologyZibo 255000China Key Laboratory of Remote Sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China North China Institute of Aerospace Engineering Langfang 065000China

The ecological environment of the Yellow River Basin has become more fragile under the combined action of natural and manmade ***,the change mechanisms of ecological vulnerability in different sub-regions and periods vary,and the reasons for this variability are yet to be ***,in this study,we proposed a new remote sensing ecological vulnerability index by considering moisture,heat,greenness,dryness,land degradation,and social economy indicators and then analyzed and disclosed the spatial and temporal change patterns of ecological vulnerability of the Yellow River Basin,China from 2000 to 2022 and its driving *** results showed that the newly proposed remote sensing ecological vulnerability index had a high accuracy,at 86.36%,which indicated a higher applicability in the Yellow River *** 2000 to 2022,the average remote sensing ecological vulnerability index of the Yellow River Basin was 1.03,denoting moderate vulnerability *** intensive vulnerability area was the most widely distributed,which was mostly located in the northern part of Shaanxi Province and the eastern part of Shanxi *** 2000 to 2022,the ecological vulnerability in the Yellow showed an overall stable trend,while that of the central and eastern regions showed an obvious trend of *** gravity center of ecological vulnerability migrated southwest,indicating that the aggravation of ecological vulnerability in the southwestern regions was more severe than in the northeastern regions of the *** dominant single factor of changes in ecological vulnerability shifted from normalized difference vegetation index(NDVI)to temperature from 2000 to 2022,and the interaction factors shifted from temperature∩NDVI to temperature∩precipitation,which indicated that the global climate change exerted a more significant impact on regional *** above results could provide decision support for the ecological protection and restoration of the Y

关键词： ecological vulnerability spatio-temporal pattern gravity center migration trajectory interaction factors geodetector green index q-value

Cosmological interpretation for the stochastic signal in pulsar timing arrays

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 43-50页

作者： Yu-mei Wu Zu-Cheng Chen Qing-guo Huang School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China Advanced Institute of Natural Sciences Beijing Normal UniversityZhuhai 519087China Department of Physics and Synergistic Innovation Center for Quantum Effects and Applications Hunan Normal UniversityChangsha 410081China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

The pulsar timing array(PTA)collaborations have recently reported compelling evidence for a stochastic signal consistent with a gravitational-wave *** this paper,we combine the latest data sets from NANOGrav,PPTA,and EPTA to explore cosmological interpretations for the PTA signal from first-order phase transitions,domain walls,and cosmic strings,*** find that the domain wall model is strongly disfavored with the Bayes factors compared with the first-order phase transitions and cosmic strings being 1/90 and 1/189,respectively,breaking the degeneracy among these models in individual data *** also find that:(1)a strong phase transition at temperatures below the electroweak scale is favored,and the bubble collisions make the dominant contribution to the energy density spectrum;(2)a small reconnection probability p<1.55×10^(-1)allowed by strings in(super)string theory is favored at the 95%confidence level,and ground-based detectors can further constrain the parameter space.

关键词： puslar timing arrays gravitational-wave background first-order phase transitions domain walls cosmic strings

Facile synthesis of composite polyferric magnesium-silicate-sulfate coagulant with enhanced performance in water and wastewater

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 574-584页

作者： Xiangtao Huo Rongxia Chai Lizheng Gou mei Zhang Min guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The coagulation process is a widely applied technology in water and wastewater *** composite polyferric mag-nesium-silicate-sulfate(PFMS)coagulants were synthesized using Na_(2)SiO_(3)·9H_(2)O,Fe_(2)(SO_(4))_(3),and MgSO_(4) as raw materials in this *** effects of aging time,Fe:Si:Mg,and OH:M molar ratios(M represents the metal ions)on the coagulation performance of the as-pre-pared PFMS were systematically investigated to obtain optimum *** results showed that PFMS coagulant exhibited good co-agulation properties in the treatment of simulated humic acid-kaolin surface water and reactive dye *** the molar ratio was controlled at Fe:Si:Mg=2:2:1 and OH:M=0.32,the obtained PFMS presented excellent stability and a high coagulation *** removal efficiency of ultraviolet UV254 was 99.81%,and the residual turbidity of the surface water reached 0.56 NTU at a dosage of 30 mg·L^(-1).After standing the coagulant for 120 d in the laboratory,the removal efficiency of UV254 and residual turbidity of the surface wa-ter were 88.12%and 0.68 NTU,respectively,which accord with the surface water treatment *** addition,the coagulation performance in the treatment of reactive dye wastewater was greatly improved by combining the advantages of magnesium and iron *** with polyferric silicate-sulfate(PFS)and polymagnesium silicate-sulfate(PMS),the PFMS coagulant played a better decolor-ization role within the pH range of 7-13.

关键词： polyferric-magnesium-silicate-sulfate composite coagulants water and wastewater excellent stability high coagulation ef-ficiency decolorization

A review on current development of thermophotovoltaic technology in heat recovery

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International Journal of Extreme Manufacturing 2024年第2期6卷 297-323页

作者： Shuni Chen Yanming guo Qinghui Pan yong Shuai Ministry of Industry and Information Technology Key Laboratory of Aerospace Thermophysics School of Energy Science and EngineeringHarbin Institute of TechnologyHarbin 150001People’s Republic of China

The burning of fossil fuels in industry results in significant carbon emissions,and the heat generated is often not fully *** high-temperature industries,thermophotovoltaics(TPVs)is an effective method for waste heat *** review covers two aspects of high-efficiency TPV systems and industrial waste heat *** the system level,representative results of TPV complete the systems,while selective emitters and photovoltaic cells in the last decade are *** key points of components to improve the energy conversion efficiency are further analyzed,and the related micro/nano-fabrication methods are *** the application level,the feasibility of TPV applications in high-temperature industries is shown from the world waste heat utilization *** potential of TPV in waste heat recovery and carbon neutrality is illustrated with the steel industry as an example.

关键词： thermophotovoltaic waste heat recovery micro/nano-fabrication carbon neutrality

XOR spin logic operated by unipolar current based on field-free spin-orbit torque switching induced by a lateral interface

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Rare Metals 2024年第8期43卷 3868-3875页

作者： Yan-Ru Li mei-Yin Yang guo-Qiang Yu Bao-Shan Cui Jin-Biao Liu yong-Liang Li Qi-Ming Shao Jun Luo Key Laboratory of Microelectronic Devices and Integrated Technology Institute of MicroelectronicsChinese Academy of Sciences(IMECAS)Beijing 100029China University of Chinese Academy of Sciences(UCAS) Beijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education Lanzhou UniversityLanzhou 730000China Department of Electronic and Computer Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China

Spin logics have emerged as a promising avenue for the development of logic-in-memory *** particular,the realization of XOR spin logic gates using a single spin-orbit torque device shows great potential for low-power stateful logic circuits in the next *** this study,we successfully obtained the XOR logic gate by utilizing a spin-orbit torque device with a lateral interface,which was created by local ion implantation in the Ta/Pt/Co/Ta Hall device exhibiting perpendicular magnetic *** angle of the lateral interface is set at 45°relative to the current direction,leading to the competition between symmetry breaking and current-driven Néel-type domain wall ***,the field-free magnetic switching reversed is realized by the same sign of current amplitude at this *** on this field-free magnetic switching behavior,we successfully proposed an XOR logic gate that could be implemented using only a single spin-orbit torque Hall *** study provides a potentially viable approach toward efficient spin logics and in-memory computing architectures.

关键词： Filed-free magnetic switching Spin-orbit torque XOR logic gate Lateral interface

Value of the Ratio of Occluder Versus Atrial Septal Length for Predicting Arrhythmia Occurrence after Transcatheter Closure in Children with Ostium Secundum Atrial Septal Defect

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Chinese Medical Journal 2015年第12期128卷 1574-1578页

作者： mei Jin Wen-Hang Ding Xiao-Fang Wang Bao-Jing guo yong-mei Liang Yan-Yan Xiao Chu-Fan Sun Department of Pediatric Cardiology Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Background：Transcatheter occlusion has been applied to treat ostium secundum atrial septal defect （OS ASD） since *** the clinical practice,several postoperative complications including arrhythmia have been *** study aimed to evaluate the value of the ratio of atrial septal occluder （ASO） versus atrial septal length （ASL） for predicting arrhythmia occurrence after transcatheter closure in children with OS ***：Six hundred and fifty-one children diagnosed with OS ASD underwent occlusion procedures after completing routine *** onsets and types of arrhythmia both during and after the occlusion procedures were *** were given based on the individual types of *** binary logistic regression analysis and receiver-operating characteristic （ROC） curve were used in the analysis of value of the ratio of ASO/ASL for predicting postoperative arrhythmia ***：Transcather occlusions were conducted in 651 children,among whom 7 children had different types and degrees of arrhythmia,with an incidence of 1.1%.The types of arrhythmia included sinus bradycardia,atrial premature beats,bundle branch block,and different degrees of atrioventricular *** electrocardiograph findings were resumed in these 7 patients following active therapies such as corticoids,nutrition,and *** binary logistic regression and ROC analysis suggested that the ratio of ASO/ASL exhibited an intermediate predictive value for predicting arrhythmia occurrence after occlusion procedures.A cut-offvalue of 0.576 in the ratio provided a sensitivity of 87.5% and a specificity of 76.2% with an area under the ROC curve of 0.791 （95% confidence intervals,0.655-0.926;P 〈 0.05） in predicting arrhythmia occurrence after the closure ***：The ratio of ASO/ASL might be a useful index for predicting arrhythmia occurrence after closure procedures in children with OS ASD.

关键词： Arrhythmia Atrial Septal Defect Atrial Septal Length Atrial Septal Occluder Transcatheter Closure

A Local Macroscopic Conservative(LoMaC)Low Rank Tensor Method with the Discontinuous Galerkin Method for the Vlasov Dynamics

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Communications on Applied Mathematics and Computation 2024年第1期6卷 550-575页

作者： Wei guo Jannatul Ferdous Ema Jing-mei Qiu Department of Mathematics and Statistics Texas Tech UniversityLubbockTX70409USA Department of Mathematical Sciences University of DelawareNewarkDE19716USA

In this paper,we propose a novel Local Macroscopic Conservative(LoMaC)low rank tensor method with discontinuous Galerkin(DG)discretization for the physical and phase spaces for simulating the Vlasov-Poisson(VP)*** LoMaC property refers to the exact local conservation of macroscopic mass,momentum,and energy at the discrete *** recently developed LoMaC low rank tensor algorithm(arXiv:2207.00518)simultaneously evolves the macroscopic conservation laws of mass,momentum,and energy using the kinetic flux vector splitting;then the LoMaC property is realized by projecting the low rank kinetic solution onto a subspace that shares the same macroscopic *** paper is a generalization of our previous work,but with DG discretization to take advantage of its compactness and flexibility in handling boundary conditions and its superior accuracy in the long *** algorithm is developed in a similar fashion as that for a finite difference scheme,by observing that the DG method can be viewed equivalently in a nodal *** the nodal DG method,assuming a tensorized computational grid,one will be able to(i)derive differentiation matrices for different nodal points based on a DG upwind discretization of transport terms,and(ii)define a weighted inner product space based on the nodal DG grid *** algorithm can be extended to the high dimensional problems by hierarchical Tucker(HT)decomposition of solution tensors and a corresponding conservative projection *** a similar spirit,the algorithm can be extended to DG methods on nodal points of an unstructured mesh,or to other types of discretization,e.g.,the spectral method in velocity *** numerical results are performed to showcase the efficacy of the method.

关键词： Hierarchical Tucker(HT)decomposition Conservative SVD Energy conservation Discontinuous Galerkin(DG)method