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社科纵横 2022年第5期37卷 125-129页

作者：胡苗甘肃省社会科学院农村发展研究所甘肃兰州730070

基于乡村振兴视角,以文献资料、问卷调查、实地调研为基础,运用数量经济学方法,从甘肃省发展最为薄弱的小城镇着手,构建建制镇综合竞争力评价体系,系统地研究建制镇发展方向、布局、定位等问题,旨在为甘肃省新型城镇化的推进提供有益借鉴。

关键词：区域差异建制镇乡村振兴

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兰州经济区土地利用空间结构变化分析

干旱区资源与环境 2007年第8期21卷 92-95页

作者：胡苗石培基齐志男西北师范大学地理与环境科学学院兰州730070

兰州经济区位于西陇海-兰新经济带甘肃段中段,是黄河上游经济区的核心。本文在全面分析了兰州经济区1990～2000年土地利用数量变化、空间变化的基础上,提出了今后兰州经济区土地空间结构优化的思路,从而为土地资源的管理和持续利用提供... 详细信息

兰州经济区位于西陇海-兰新经济带甘肃段中段,是黄河上游经济区的核心。本文在全面分析了兰州经济区1990～2000年土地利用数量变化、空间变化的基础上,提出了今后兰州经济区土地空间结构优化的思路,从而为土地资源的管理和持续利用提供有效的决策支持。

关键词：土地利用空间结构分析兰州经济区

Changes in extreme high temperature warning indicators over China under different global warming levels

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Science China Earth Sciences 2024年第6期67卷 1895-1909页

作者： Yuxia ZHANG Ying SUN Ting hu Chinese Academy of Meteorological Sciences Beijing 100081China National Climate Center Laboratory for Climate StudiesChina Meteorological AdministrationBeijing 100081China

High temperature warning indicators play a pivotal role in meteorological departments,serving as crucial criteria for issuing warnings that guide both social production and daily *** their importance,limited studies have explored the relationship between different global warming levels and changes in high temperature warning *** this study,we analyze data from 2,419 meteorological stations over China and utilize the Coupled Model Intercomparison Project Phase 6(CMIP6)models to examine historical changes in high temperature warning indicators used by the China Meteorological *** evaluate model performance and estimate future changes in these indicators using an annual cycle bias correction *** results indicate that since 1961,the number of high temperature days(TX35d and TX40d)and length of season(TX40d and TX40l)with daily maximum temperature reaching or exceeding 35℃ and 40℃ have increased over *** intensity of high temperatures(TXx)has strengthened and the geographical extent affected by high temperatures has *** 2022,the occurrence of 40℃ high temperatures surges,with Eastern China experiencing a two-day increase in TX40d and an extended seasonal length in TX40l by over five *** CMIP6 models have underestimated the high temperature indictors associated with 35℃ during historical periods,notable difference is not observed between the models and observations for TX40d and TX40l,given their rare ***,future projections,after bias correction,indicate that the increasing trends for 35℃ and 40℃ high temperature days and length of season become more pronounced than the raw projection,suggesting a more severe increase than that anticipated *** global warming intensifies,the high temperature days and length of season are projected to increase non-linearly,while the intensity of high temperatures is expected to increase *** every 1℃ increase in global temperature,the intensity is

关键词： Extreme high temperatures Meteorological warning CMIP6 Global warming levels Future projection

Tensor perturbations from bounce inflation scenario in f(Q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun hu Tanmoy Paul Taotao Qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations *** is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGWs)that are to be detected by the next generation of GW *** discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation *** general form of the tensor power spectrum is obtained both for large as well as small scale *** a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(Q)bounce-inflation ***,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modified gravity cosmological perturbations

Coupled conditional nonlinear optimal perturbations and their application to ENSO ensemble forecasts

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Science China Earth Sciences 2024年第3期67卷 826-842页

作者： Wansuo DUAN Lei hu Rong FENG LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Limitations are existed in current ensemble forecasting initial perturbation methods for describing the interactions among various spheres of the Earth system. In this study, a new method is proposed, namely, the coupled conditional nonlinear optimal perturbation(C-CNOP) method, which incorporates multisphere interactions much appropriately. The El Nino-Southern Oscillation(ENSO) is a typical ocean-atmosphere “coupling”(or “interaction”) phenomenon. The C-CNOP method is applied to ensemble forecasting of ENSO. It is demonstrated that the C-CNOP method can generate coupled initial perturbations(CPs) that appropriately consider initial ocean-atmosphere coupling uncertainty for ENSO ensemble forecasts. Results reveal that the CPs effectively improve the ability of ENSO ensemble-mean forecasts in both temporal variability of Nio3.4 sea surface temperature anomalies(SSTAs) and spatial variability of ENSO mature-phase SSTAs. Notably, despite the weakest ocean-atmosphere coupling strength in the tropical Pacific occurring during the boreal spring and summer, CPs still capture the uncertainties of this weak coupling when ENSO predictions are initialized at these seasons. This performance of CPs significantly suppresses the rapid increase of ENSO prediction errors due to the high ocean-atmosphere coupling instability during these seasons, and thus effectively extends the lead time of skillful ENSO forecasting. Hence, the C-CNOP method is a suitable initial perturbation approach for ENSO ensemble forecast that can describe initial ocean-atmosphere coupling uncertainty. It is expected that the CCNOP method plays a significant role in predictions of other high-impact climate phenomena, and even future Earth system predictions.

关键词： Ensemble forecast Multisphere interaction Initial perturbations ENSO

Carbonation of Dicalcium Silicate Enhanced by Ammonia Bicarbonate and Its Mechanism

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 69-74页

作者：周浩刘鹏 WANG Fazhou hu Chuanlin School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

The strength development law of γ-type dicalcium silicate (γ-C_(2)S) under different carbonation processes was investigated,and the carbonation mechanism of γ-C_(2)S under the action of NH_(4)HCO_(3) was clarified by using a wide range of test methods,including XRD and SEM.A method of saturated NH_(4)HCO_(3) solution as a curing agent was identified to improve the carbonation efficiency and enhance the carbonation degree of γ-C_(2)S,and then a high-strength carbonated specimen was *** analysis and SEM morphology analysis were conducted on the carbonised specimens obtained under atmospheric pressure carbonisation conditions using the curing *** was found that γ-C_(2)S could perform carbonisation well under atmospheric pressure,which promoted the carbonisation efficiency and decreased the carbonisation cost ***,a new carbonisation process solution was proposed for the rapid carbonisation of γ-C_(2)S.

关键词： type dicalcium silicate carbonization process curing agent atmospheric carbonization

Precise construction of RuPt dual single-atomic sites to optimize oxygen electrocatalytic behaviors for high-performance Zn-air batteries

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Journal of Energy Chemistry 2024年第10期97卷 520-528,I0011页

作者： Xiaolin hu Zhenkun Wu Chaohe Xu School of Science Chongqing Key Laboratory of New Energy Storage Materials and DevicesChongqing University of TechnologyChongqing 400054China School of Chemistry and Engineering Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The development of redox bifunctional electrocatalysts with high performance,low cost,and long lifetimes is essential for achieving clean energy *** study proposed an atom capture strategy for anchoring dual single atoms(DSAs)in a zinc-zeolitic imidazolate framework(Zn-ZIF),followed by calcination under an N_(2) atmosphere to synthesize ruthenium-platinum DSAs supported on a nitrogendoped carbon substrate(RuPt DSAs-NC).Theoretical calculations showed that the degree of Ru 5dxz-~*O 2p_x orbital hybridization was high when^(*)O was adsorbed at the Ru site,indicating enhanced covalent hybridization of metal sites and oxygen ligands,which benefited the adsorption of intermediate *** presence of the RuPtN_6 active center optimized the absorption-desorption behavior of intermediates,improving the electrocatalytic performance of the oxygen reduction reaction(ORR)and the oxygen evolution reaction(DER),RuPt DSAs-NC exhibited a 0.87 V high half-wave potential and a 268 mV low overpotential at 10 mA cm^(-2)in an alkaline ***,rechargeable zinc-air batteries(ZABs)achieved a peak power density of 171 MW cm^(-2).The RuPt DSAs-NC demonstrated long-term cycling for up to 500 h with superior round-trip *** study provided an effective structural design strategy to construct DSAs active sites for enhanced electrocata lytic performance.

关键词： Dual single atoms catalysts Atom capture Oxygen reduction reaction Oxygen evolution reaction Rechargeable Zn-air batteries

Enhancement in the Hg^(0) oxidation efficiency and sulfur resistance of CuCl_(2)-modified MnO_(x)-CeO_(x) nanorod catalysts

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 680-686页

作者： Shujie GAO Yongjin hu Zhichang JIANG Xiaoxiang WANG Dong YE Changxing hu College of Quality&Safety Engineering China Jiliang UniversityHangzhou 310018China Key Laboratory of Biomass Chemical Engineering of Ministry of Education Institute of Industrial Ecology and EnvironmentCollege of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China School of Mechatronics and Energy Engineering Ningbo Tech UniversityNingbo 315100China

In this study,a series of CuCl_(2)-modified MnO_(x)-CeO_(x)nanorods were synthesized for the oxidation of Hg^(0).The addition of CuCl_(2)resulted in an enhancement in the catalyst’s Hg^(0)oxidation ability,and Hg^(0)oxidation efficiency reached>97%from 150 to 250°*** the MnO_(x)-CeO_(x)catalysts,Mn^(4+)played the role of the active species for Hg^(0)oxidization,but in the CuCl_(2)-doped catalysts Cl−also contributed to Hg^(0)oxidation,conferring the superior performance of these *** introduction of SO_(2) led to a decrease in the availability of Mn^(4+),and the Hg^(0)oxidation efficiency of MnO_(x)-CeO_(x)decreased from about 100%to about 78%.By contrast,CuCl_(2)-promoted samples maintained a Hg^(0)oxidation efficiency of about 100%during the SO_(2) deactivation cycle due to the high reactivity of Cl−.

关键词： Hg^(0)oxidation CuCl_(2)modification MnO_(x)-CeO_(x)nanorods Sulfur resistance O_(x)idation activity

基于GC/Q-TOF MS技术鉴定S-zorb汽油中噻吩类化合物

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分析试验室 2021年第1期40卷 105-110页

作者：任绪金黄少凯胡淼吴青中海油炼油化工科学研究院北京102209 中国海洋石油集团科技发展部北京100010

结合气相色谱分离技术和MS/MS串联质谱筛查技术,通过选定目标母离子进行碰撞诱导解离,获取精确质量子离子信息,实现汽油馏分中噻吩类化合物的痕量筛查分析。选取5种不同碳数取代噻吩类化合物作为标准物绘制定量标准曲线,建立了基于气相... 详细信息

结合气相色谱分离技术和MS/MS串联质谱筛查技术,通过选定目标母离子进行碰撞诱导解离,获取精确质量子离子信息,实现汽油馏分中噻吩类化合物的痕量筛查分析。选取5种不同碳数取代噻吩类化合物作为标准物绘制定量标准曲线,建立了基于气相色谱-四极杆串联飞行时间质谱(GC/Q-TOF M S)直接测定汽油中噻吩类化合物的方法。利用该方法研究了S-Zorb汽油中噻吩类化合物(TPs)的脱除规律。结果表明,S-zorb汽油噻吩类化合物的脱除难易程度与其取代基的位置有关,2-甲基噻吩相比3-甲基噻吩更难脱除,2,5-二甲基噻吩、2,3,5-三甲基噻吩分别为C2-TPs和C3-TPs的主要剩余噻吩类化合物。

关键词： S-zorb汽油噻吩类化合物气相色谱四极杆串联飞行时间质谱

GraphFlow+:Exploiting Conversation Flow in Conversational Machine Comprehension with Graph Neural Networks

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Machine Intelligence Research 2024年第2期21卷 272-282页

作者： Jing hu Lingfei Wu Yu Chen Po hu Mohammed J.Zaki School of Computer Science Central China Normal UniversityWuhan 430079China Pinterest San Francisco 94016USA Meta Mountain View 94039USA Rensselaer Polytechnic Institute Troy 12180USA

The conversation machine comprehension(MC)task aims to answer questions in the multi-turn conversation for a single ***,recent approaches don’t exploit information from historical conversations effectively,which results in some references and ellipsis in the current question cannot be *** addition,these methods do not consider the rich semantic relationships between words when reasoning about the passage *** this paper,we propose a novel model GraphFlow+,which constructs a context graph for each conversation turn and uses a unique recurrent graph neural network(GNN)to model the temporal dependencies between the context graphs of each ***,we exploit three different ways to construct text graphs,including the dynamic graph,static graph,and hybrid graph that combines the *** experiments on CoQA,QuAC and DoQA show that the GraphFlow+model can outperform the state-of-the-art approaches.

关键词： Conversational machine comprehension(MC) reading comprehension question answering graph neural networks(GNNs) natural language processing(NLP)