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Structure of Non-stoichiometric Sr_6Gd_(0.61)Sc_(1.39)(BO_3)_6 Crystal

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Chinese journal of Structural Chemistry 2004年第5期23卷 537-539页

作者： HUZu-Shu LINZhou-Bin CHENjiu-Tong WANGGuo-fon StateKeyLaboratoryofStructuralChemistry FujianInstituteofResearchontheStructureofMatterTheChineseAcademyofSciencesFuzhouFujian350002China GraduateSchooloftheChineseAcademyofSciences Beijing100039China

The crystal of the title compound Sr6Gd0.61Sc1.39(BO3)6 (mr = 1037.00) was grown by Czochralski method. It crystallizes in trigonal, space group 3Rwith a = 12.415(2), c = 9.274(2) ? Z = 3, V = 1238.0(4) 3, Dc = 4.173 g/cm3, l(moKa) = 0.71073 ? m = 22.278 mm-1, F(000) = 1411, S = 1.213, the final R = 0.0577 and wR = 0.1414 for 401 observed reflections with I>2s(I). In the structure Gd(1)O6 (Gd(1) = Gd0.46 + Sc0.54) and Gd(2)O6 (Gd(2)= Gd0.15 + Sc0.85) are alternately stacked between the planar triangular BO3 groups to form chains extending along the trigonal axis. These chains are connected through the 9-coordinate Sr atoms.

关键词： crystal structure Sr6Gd0.61Sc1.39(BO3)6 crystal non-stoichiometric

Effect of droplet size on the jet breakup characteristics of n-butanol during impact on a heated surface

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journal of Traffic and Transportation Engineering(English Edition) 2020年第3期7卷 320-330页

作者： Han Wu Longmin Tang Chunze Cen Chia-fon Lee School of mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Department of mechanical Aerospace and Ciuil EngineeringUniversity of ManchesterManchester M139PLUK Department of mechanical Science and Engineering University of Illinois at Urbana-ChampaignUrbana1L 61801USA

jet breakup during droplet impacted on heated surface has received wide concerns due to its *** Weber number(We)is a common used dimensionless parameter to classify and analyze the phenomenon,but it is unable to summarize all detailed phenomenon variations and related ***,the effect of droplet size on jet breakup was investigated by considering its significant difference in various *** behavior of n-butanol droplets with diameter range from 1.71 mm to 2.84 mm impacts a heated surface with jet breakup was recorded by backlit *** parameters,the jet breakup time,the jet breakup length and the jet ligament diameter,were analyzed to illustrate the *** results showed that these parameters are affected by the droplet size largely at 10meter reduces with Weber number for all initial size droplets while the larger initial droplet corresponds to larger *** breakup time,breakup length and jet ligament diameter increase with the initial *** time of jet breakup versus agrees well with the theory of Rayleigh instability regardless of droplet *** addition,the jet breakup phenomenon was observed to evolve into pancake bouncing with an ultrafine high-speed jet when the We was above 50.

关键词： Energy engineering Droplet impact Heated surface Droplet size jet breakup n-butanol

A Tutorial Review of the Solar Power Curve: Regressions, model Chains, and Their Hybridization and Probabilistic Extensions

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Advances in Atmospheric Sciences 2024年第6期41卷 1023-1067页

作者： Dazhi YANG Xiang’ao XIA martin jános mAYER School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Key Laboratory for middle Atmosphere and Global Environment Observation(LAGEO) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Department of Energy Engineering Faculty of Mechanical EngineeringBudapest University of Technology and EconomicsMűegyetem rkp.3Budapest H-1111Hungary

Owing to the persisting hype in pushing toward global carbon neutrality,the study scope of atmospheric science is rapidly *** numerous trending topics,energy meteorology has been attracting the most attention *** essential skill of solar energy meteorologists is solar power curve modeling,which seeks to map irradiance and auxiliary weather variables to solar power,by statistical and/or physical *** this regard,this tutorial review aims to deliver a complete overview of those fundamental scientific and engineering principles pertaining to the solar power *** power curves can be modeled in two primary ways,one of regression and the other of model *** classes of modeling approaches,alongside their hybridization and probabilistic extensions,which allow accuracy improvement and uncertainty quantification,are scrutinized and contrasted thoroughly in this review.

关键词： review energy meteorology solar power curve model chain solar power prediction

modelling the impact of timelines of testing and isolation on disease control

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Infectious Disease modelling 2023年第1期8卷 58-71页

作者： ao Li Zhen Wang Seyed m.moghadas Agent-Based modelling Laboratory York UniversityTorontoOntarioM3J 1P3Canada

Testing and isolation remain a key component of public health responses to both persistent and emerging infectious *** the value of these measures have been demonstrated in combating recent outbreaks including the COVID-19 pandemic and monkeypox,their impact depends critically on the timelines of testing and start of isolation during the course of *** investigate this impact,we developed a delay differential model and incorporated age-since-symptom-onset as a parameter for delay in *** then used the model to compare the outcomes of reverse-transcription polymerase chain reaction(RT-PCR)and rapid antigen(RA)testing methods when isolation starts either at the time of testing or at the time of test *** the model with estimates of SARS-CoV-2 infection and diagnostic sensitivity of the tests,we found that the reduction of disease transmission using the RA test can be comparable to that achieved by applying the RT-PCR *** constraints and inevitable delays associated with sample collection and laboratory assays in RT-PCR testing post symptom onset,self-administered RA tests with short turnaround times present a viable alternative for timely isolation of infectious cases.

关键词： Testing Isolation Delay equations Simulations Turnaround time

Alectinib: a novel second generation anaplastic lymphoma kinase(ALK) inhibitor for overcoming clinically-acquired resistance

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Acta Pharmaceutica Sinica B 2015年第1期5卷 34-37页

作者： Zilan Song meining Wang ao Zhang CAS Key Laboratory of Receptor Research Synthetic Organic & Medicinal Chemistry LaboratoryShanghai Institute of Materia Medica (SIMM) Chinese Academy of Sciences

The development of inhibitors for the tyrosine anaplastic lymphoma kinase (ALK) has advanced rapidly, driven by biology and medicinal chemistry. The first generation ALK inhibitor crizotinib was granted US FDA approval with only four years of preclinical and clinical testing. Although this drug offers significant clinical benefit to the ALK-positive patients, resistance has been developed through a variety of mechanisms. In addition to ceritinib, alectinib is another second-generation ALK inhibitor launched in 2014 in japan. This drug has a unique chemical structure bearing a 5H-benzo[b] carbazol-11(611)-one structural scaffold with an IC50 value of 1.9 nmol/L, and is highly potent against ALK bearing the gatekeeper mutation L1196m with an IC50 of 1.56 nmoL/L. In the clinic, alectinib is highly efficacious in treatment of ALK-positive non-small cell lung cancer (NSCLC), and retains potency to combat crizotinib-resistant ALK mutations L11.96.m, F1174L, R1275Q and C1156Y. (C) 2015 Chinese Pharmaceutical Association and Institute of materia medica, Chinese Academy of medical Sciences. Production and hosting by Elsevier B.V. All rights reserved.

关键词： Tyrosine anaplastic lymphoma kinase Alectinib Crizotinib Non-suaall cell lung cancer Resistance ALK mutations EmL4-ALK

Rural labor migration and farmers’arrangements of rice production systems in Central China:Insight from the intergenerational division of labor

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journal of Integrative Agriculture 2024年第9期23卷 3200-3214页

作者： Xue Shen Quanyu Yang Rongjun ao Shengsheng Gong Key Laboratory for Geographical Process Analysis&Simulation of Hubei Province/College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China

Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied *** migration in rural China has taken new forms in recent *** has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm *** phenomenon has notably shaped the intergenerational division of labor(IDL)within ***,it remains to be seen how farmers adjust their rice production systems in response to the *** age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the *** on a representative household survey of 1,752 rice farmers in the Hubei Province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service *** analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational *** transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL *** study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security.

关键词： labor migration intergenerational division of labor rice production systems fuzzy regression discontinuity Central China

Response analyses on the drill-string channel for logging while drilling telemetry

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Petroleum Science 2023年第5期20卷 2796-2808页

作者： ao-Song Zhao Xiao He Hao Chen Xiu-ming Wang State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Beijing Engineering Research Center of Sea Deep Drilling and Exploration Institute of AcousticsChinese Academy of SciencesBeijing100190China

Downhole acoustic telemetry(DAT),using a long drill string with periodical structures as the channel,is a prospective technology for improving the transmission rate of logging while drilling(LWD)*** studies only focused on the acoustic property of a free drill string and neglected the coupling between pipes and fluid-filled *** addition to the drill-string waves,a series of fluid waves are recorded in the DAT channel,which has not been investigated *** channel characteristics result in lower transmission rates and stability than ***,a more realistic channel model is needed considering the fluid-filled *** this paper,we propose a hybrid modeling method to investigate the response characteristics of the DAT *** combining the axial wavenumbers and excitation functions of mode waves in radially layered LWD structures,the channel model is approximated to the 1-D propagation,which considers transmission,reflection,and interconversion of the drillstring and fluid *** proposed 1-D approximation has been well validated by comparing the 2-D finite-difference *** is revealed that the transmitted and converted fluid waves interfere with the drill-string wave,which characterizes the DAT channel as a particular coherent multi-path *** a fluid-filled borehole surrounds the drill string,the channel responses exhibit considerable delay as well as strong frequency selectivity in amplitude and *** new findings suggest that the complexity of the channel response has been underestimated in the past,and therefore channel measurements on the ground are *** address these channel characteristics,we apply a noncoherent demodulation *** transmission rate for synthetic data reaches 15 bps in a 94.5 m long channel,indicating that the acoustic telemetry is promising to break the low-speed limitation of mud-pulse telemetry.

关键词： Logging while drilling Borehole geophysics Downhole acoustic telemetry Channel modeling Frequency selectivity

Synthesis of novel biscalixarene-tube containing two kinds of calix[4]arene derivative units

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Chinese Chemical Letters 2008年第1期19卷 9-11页

作者： Fa Fu Yang Li m ing Liu Chao Hui Liu Xi-ao Hua Zheng Yu Guo College of Chemistry and materials Fujian Normal University Fuzhou 350007 China

A novel biscalixarene with two kinds of calix[4]arene derivative units connected by four bridging chains, was facilely＇ synthesized by ＂1 ＋ 1＂ condensation mode in high yield. The element analyses, ESI-mS, ^1H NmR and ^1H-^1H COSY spectrum showed that the calix[4]arene units of compound 4 were in cone conformations and compound 4 possessed biscalixarene-tube structure. 2007 Fa Fu Yang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Biscalixarene Tube Synthesis ^1H-^1H COSY

Dynamic deformation behavior of a FeCrNi medium entropy alloy

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journal of materials Science & Technology 2022年第5期100卷 120-128页

作者： ao Fu Bin Liu Zezhou Li Bingfeng Wang Yuankui Cao Yong Liu State Key Laboratory of Powder metallurgy Central South UniversityChangsha 410083China Department of mechanical and Aerospace Engineering University of CaliforniaSan DiegoUnited States School of materials Science and Engineering Central South UniversityChangsha 410083China

Deformation behavior of a FeCrNi medium entropy alloy(mEA)prepared by powder metallurgy(P/m)method was investigated over a wide range of strain *** FeCrNi mEA exhibits high strain-hardening ability,which can be attributed to the multiple deformation mechanisms,including dislocation slip,deformation induced stacking fault and mechanical *** shear localization behavior of the FeCrNi mEA was also analyzed by dynamically loading hat-shaped specimens,and the distinct adiabatic shear band cannot be observed until the shear strain reaches~*** microstructures within and outside the shear band exhibit different characteristics:the grains near the shear band are severely elongated and significantly refined by dislocation slip and twinning;inside the shear band,the initial coarse grains completely disappear,and transform into recrystallized ultrafine equiaxed grains by the classical rotational dynamic recrystallization ***,microvoids preferentially nucleate in the central areas of the shear band where the temperature is very high and the shear stress is highly *** microvoids will coalesce into microcracks with the increase of strain,which eventually leads to the fracture of the shear band.

关键词： medium entropy alloys mechanical response Dynamic shear properties Grain refinement Adiabatic shear band