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| 1 | Synthesis, characterization and dielectric properties of a novel temperature stable(1-x)CoTiNb2O8-xZnNb2O6 ceramic显示文摘(1-x)CoTiNb2O8-x ZnNb2O6 microwave dielectric ceramics were prepared via the conventional solid-state reaction route with the aim of reducing thetf value and improving the thermal stability.The phase composition and the microstructure were investigated using X-ray diffraction,Raman spectra,and scanning electron microscopy.A set of phase transitions which were induced by composition had been confirmed via the sequence:rutile structure→coexistence of rutile and columbite phase→columbite phase.For(1-x)CoTiNb2O8-x ZnNb2O6 microwave dielectric ceramics,the addition of ZnNb2O6 content(x=0–1)led to the decrease ofer from 62.98 to 23.94.As a result of the high Q×?of ZnNb2O6 ceramics,the increase of ZnNb2O6 content also led to the lower sintering temperatures and the higher Q×?values.Thetf value was reduced from+108.04(x=0)to–49.31 ppm/℃(x=1).Among them,high density 0.5CoTiNb2O8-0.5ZnNb2O6 ceramics were obtained at 1175℃with excellent microwave dielectric properties of εr 39.2,Q×? 40013 GHz,and tf+3.57 ppm/℃. | Mengjuan WU Yingchun ZHANG Maoqiao XIANG | 2019 | Journal of Advanced Ceramics2019，8，2： | 6 |
| 2 | Ultrabroadband and multiband infrared/terahertz photodetectors with high sensitivity显示文摘Broadband response is pursued in both infrared(IR)and terahertz(THz)detection technologies,which find their applications in both terrestrial and astronomical realms.Herein,we report an ultrabroadband and multiband IR/THz detector based on blocked-impurity-band detecting principle.The detectors are prepared by implanting phosphorus into germanium(Ge:P),where photoresponses with a P impurity band,a self-interstitial defect band,and a vacancy-P(V-P)pair defect band are realized simultaneously.The response spectra of the detectors show ultrabroad and dual response bands in a range of 3-28μm(IR band)and 40-165μm(THz band),respectively.Additionally,a tiny mid-IR(MIR)band within 3-4.2μm is embedded in the IR band.The THz band arises from the P impurity band,whereas the IR and the MIR bands are ascribed to the two defect bands.At150 m V and 4.5 K,the peak detectivities of the three bands are obtained as 2.9×10^(12) Jones(at 3.9μm),6.8×10^(12) Jones(at 16.3μm),and 9.9×10^(12) Jones(at 116.5μm),respectively.The impressive coverage andsensitivity of the detectors are promising for applications in IR and THz detection technologies. | JIAQI ZHU HE ZHU MENGJUAN LIU YAO WANG HANLUN XU NASIR ALI HUIYONG DENG ZHIYONG TAN JUNCHENG CAO NING DAI HUIZHEN WU | 2021 | Photonics Research2021，9，11： | 2 |
| 3 | Analysis of COVID-19 Guideline Quality and Change of Recommendations:A Systematic Review显示文摘Background.Hundreds of coronavirus disease 2019(COVID-19)clinical practice guidelines(CPGs)and expert consensus statements have been developed and published since the outbreak of the epidemic.However,these CPGs are of widely variable quality.So,this review is aimed at systematically evaluating the methodological and reporting qualities of COVID-19 CPGs,exploring factors that may influence their quality,and analyzing the change of recommendations in CPGs with evidence published.Methods.We searched five electronic databases and five websites from 1 January to 31 December 2020 to retrieve all COVID-19 CPGs.The assessment of the methodological and reporting qualities of CPGs was performed using the AGREE II instrument and RIGHT checklist.Recommendations and evidence used to make recommendations in the CPGs regarding some treatments for COVID-19(remdesivir,glucocorticoids,hydroxychloroquine/chloroquine,interferon,and lopinavir-ritonavir)were also systematically assessed.And the statistical inference was performed to identify factors associated with the quality of CPGs.Results.We included a total of 92 COVID-19 CPGs developed by 19 countries.Overall,the RIGHT checklist reporting rate of COVID-19 CPGs was 33.0%,and the AGREE II domain score was 30.4%.The overall methodological and reporting qualities of COVID-19 CPGs gradually improved during the year 2020.Factors associated with high methodological and reporting qualities included the evidence-based development process,management of conflicts of interest,and use of established rating systems to assess the quality of evidence and strength of recommendations.The recommendations of only seven(7.6%)CPGs were informed by a systematic review of evidence,and these seven CPGs have relatively high methodological and reporting qualities,in which six of them fully meet the Institute of Medicine(IOM)criteria of guidelines.Besides,a rapid advice CPG developed by the World Health Organization(WHO)of the seven CPGs got the highest overall scores in methodological(72.8%)and reporting qualities(83.8%).Many CPGs covered the same clinical questions(it refers to the clinical questions on the effectiveness of treatments of remdesivir,glucocorticoids,hydroxychloroquine/chloroquine,interferon,and lopinavirritonavir in COVID-19 patients)and were published by different countries or organizations.Although randomized controlled trials and systematic reviews on the effectiveness of treatments of remdesivir,glucocorticoids,hydroxychloroquine/chloroquine,interferon,and lopinavir-ritonavir for patients with COVID-19 have been published,the recommendations on those treatments still varied greatly across COVID-19 CPGs published in different countries or regions,which may suggest that the CPGs do not make sufficient use of the latest evidence.Conclusions.Both the methodological and reporting qualities of COVID-19 CPGs increased over time,but there is still room for further improvement.The lack of effective use of available evidence and management of conflicts of interest were the main reasons for the low quality of the CPGs.The use of formal rating systems for the quality of evidence and strength of recommendations may help to improve the quality of CPGs in the context of the COVID-19 pandemic.During the pandemic,we suggest developing a living guideline of which recommendations are supported by a systematic review for it can facilitate the timely translation of the latest research findings to clinical practice.We also suggest that CPG developers should register the guidelines in a registration platform at the beginning for it can reduce duplication development of guidelines on the same clinical question,increase the transparency of the development process,and promote cooperation among guideline developers all over the world.Since the International Practice Guideline Registry Platform has been created,developers could register guidelines prospectively and internationally on this platform. | Siya Zhao Shuya Lu Shouyuan Wu Zijun Wang Qiangqiang Guo Qianling Shi Hairong Zhang Juanjuan Zhang Hui Liu Yunlan Liu Xianzhuo Zhang Ling Wang Mengjuan Ren Ping Wang Hui Lan Qi Zhou Yajia Sun Jin Cao Qinyuan Li Janne Estill Joseph LMathew Hyeong Sik Ahn Myeong Soo Lee Xiaohui Wang Chenyan Zhou Yaolong Chen | 2021 | Health Data Science2021，，1： | 1 |
| 4 | Unified total synthesis of eburnamine-vincamine indole alkaloids based on catalytic asymmetric hydrogenation/lactamization cascade显示文摘The enantioselective total synthesis of representative members of the eburnamine-vincamine alkaloids(+)-vincamine,(-)-eburnamonine,and(-)-criocerine has been accomplished.The synthesis took advantage of a highly stereoselective Ir-catalyzed hydrogenation/lactamization cascade reaction,which allows for the stereo-selective construction of the C/D rings as well as the installation of the critical cis-C20/C21 relative stereo-chemistry of the eburnamine-vincamine alkaloid skeleton in one pot. | Wen Zhang Yansong Xue Srihari Konduri Guodan Lin Mengjuan Wu Pei Tang Fener Chen | 2022 | Green Synthesis and Catalysis2022，3，3： | 0 |
| 5 | The impact of vertical resolution on the simulation of Typhoon Lekima (2019) by a cloud-permitting model显示文摘The impact of vertical resolution on the simulation of Typhoon Lekima(2019)is investigated using the Weather Research and Forecasting(WRF)model version 3.8.1.Results show that decreasing vertical grid spacing from approximately 1000 m to 100 m above 1 km height barely influences the simulated track.However,significant differences are found in the simulated tropical cyclone(TC)structure.The simulation with the coarsest vertical resolution shows a clear double warm-core structure.The upper warm core weakens and even disappears with the increase of vertical resolution.A broader eye and a more slantwise eyewall are observed with the increase of vertical resolution due to the vertically extended lower-level and upper-level outflow,which likely results in a weaker subsidence.Vertical grid convergence is evaluated with the simulated kinetic energy(KE)spectra.As the vertical grid spacing becomes finer than 200 m,convergent KE spectra are found in both the free atmosphere and the outer core of the TC.However,sensitivity tests reveal that the grid convergence is sensitive to the choice of the planetary boundary layer scheme. | Mengjuan LIU Lin DENG Wei HUANG Wanchen WU | 2022 | Frontiers of Earth Science2022，16，1： | 0 |
| 6 | A facile solution approach for fabrication of small-sized MoSe_(2) with few layers as an efficient hydrogen evolution electrocatalyst显示文摘Unlike fossil fuels,hydrogen is a renewable and clean energy source.It is available in a large amount and spreads throughout the world.When reacting with oxygen,hydrogen releases energy to produce water as the only product.Hence,hydrogen is a promising alternative to fossil fuels[1].Today,most of hydrogen is produced via the steam methane reforming process,in which hightemperature steam is used to produce hydrogen from a methane source.However,methane is non-renewable,and carbon dioxide is generated in the reforming process. | Weizhi WANG Wei LI Xinxin WANG Junyao WU Xuewei GU Mengjuan QI Enhong SHENG Konglin WU | 2021 | Frontiers of Materials Science2021，15，3： | 0 |
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