检索结果-南通市图书馆

Characteristics of Extreme Temperature Event and Its Response to Regional Warming in Northwest China in Past 45 Years

引用

Chinese Geographical Science 2008年第1期18卷 70-76页

作者： yang jinhu REN Chuanyou JIANG Zhihong Lanzhou institute of Arid Meteorology of China Meteorological Administration Lanzhou 730020 China Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province Lanzhou 730020 China Key Laboratory of Arid Climate Change and Disaster Reduction of China Meteorological Administration Lanzhou 730020 China Department of Atmospheric Science Nanjing University of information Science and Technology Nanjing 210044 China Department of Applied Meteorology Shenyang Agricultural University Shenyang 110161 China

Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesimal method for different stations at first,then yearly EHT and ELT events were counted up in differ-ent stations,and the characteristics of their spatio-temporal distribution were diagnosed at *** study drew follow-ing conclusions:1)The consistent anomaly distribution characteristic was the most important mode of the EHT and ELT events in Northwest China.2)The spatial distribution of the EHT and ELT events can be divided into five sub-regions,namely,the north of Qinghai and west of Gansu,the north of Xinjiang,the south of Xinjiang,the east of Northwest China and the south of Qinghai.3)The EHT events showed remarkable increasing trend in all of five sub-regions,but only in the north of Qinghai and west of Gansu area,sudden change phenomenon occurred;the ELT events showed decreasing trend in all of five sub-regions,and sudden change phenomenon occurred in Northwest China except for south of Qinghai.4)In all of five sub-regions the EHT events showed remarkable 12-14yr period os-cillation,and the ELT event showed significant 13-15yr and 7-8yr period oscillation.5)The EHT and ELT events displayed remarkable positive and negative responses to regional warming of Northwest China respectively.

关键词： extreme temperature response to warming Northwest China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental and Numerical Investigations on Ignition and LBO Performances for Staged Combustor under Sub-Atmospheric Conditions

引用

Journal of Thermal Science 2023年第3期32卷 1251-1262页

作者： ZHAO Qianpeng XU Gang MU Yong yang jinhu WANG Kaixing Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of Sciences University of Chinese Academy of Sciences Innovation Academy for Light-duty Gas Turbine

In order to effectively widen the high-altitude operating limits of the multi-swirl staged combustor,the ignition and lean blow-out(LBO)performances of the model combustor were experimentally acquired under the conditions of room temperature and sub-atmospheric pressure with the altitude ranging from 0 km to 12 ***,the isothermal flow fields inside a staged model combustor with different sub-atmospheric conditions were *** results show that the minimum ignition and LBO fuel-air ratio(FAR)increase rapidly with the increase of simulated *** addition,as the relative pressure drop of injector increases from1%to 3%,the ignition and LBO performances are gradually *** visualization of the flame by high-speed camera shows that the time-averaged flames under stable combustion have a similar distribution pattern under different pressure *** luminous intensity is stratified into dim-bright-dim layers along axial *** flame near LBO shrinks to the outlet of pilot stage with a great reduction in luminous *** numerical results reveal that with the decrease of air pressure,the air mass flow rate involved in atomization and combustion is significantly reduced,and the aerodynamic shear force of swirling air is weakened,which are adverse to atomization and fuel-air mixing for airblast atomizer and further lead to the deterioration of ignition and LBO performances.

关键词： ignition lean blow-out sub-atmospheric pressure staged combustor airblast atomizer

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental Investigation of Flame Dynamics Based on High-Speed Images in Swirl Combustion Systems

引用

Journal of Thermal Science 2023年第1期32卷 427-437页

作者： LI Yao HU Chunyan ZHAO Qianpeng yang jinhu TAN Xiangmin XU Gang Key Laboratory of Light Duty Gas Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academyof Sciences Beijing 100049China Innovation Academy for Light-Duty Gas Turbine Chinese Academy of SciencesBeijing 100190China

The interaction mechanism of internally-staged-swirling stratified flame is complex,and the pilot flame has a manifest influence on flame *** study this,a series of experimental investigations for the pilot flame has been carried out in a model swirl combustor by only supplying the pilot *** CH*chemiluminescence images of the pilot flame are acquired by a high-speed camera with a CH*bandpass filter,whose dynamic characteristics are identified by image statistical analysis and proper orthogonal decomposition(POD)*** the fast algorithm based on matrix theory proposed in this paper increases the operation efficiency and operability of *** the pilot equivalence ratioΦincrease,the pilot flame gradually shows an unstable state,whose POD energy distribution is significantly *** the unstable state,the flame dynamics include three modes—spiral motion mode,flame shedding mode,and axial oscillation mode,whose formation reasons have also been further analyzed in combination with the experimental *** the fast Fourier transform(FFT)analysis of the time coefficients for the first four POD modes indicates all the dominant frequency is 280 Hz,which means the model combustor is in *** addition,a sensitivity analysis based on the different image resolutions further reveals the robustness of the POD method and its optimization *** results emphasize the important influence of the pilot fuel flow rate on the stability of the pilot flame.

关键词： pilot flame high speed image flame dynamics proper orthogonal decomposition

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

MIL-100(V) derived porous vanadium oxide/carbon microspheres with oxygen defects and intercalated water molecules as high-performance cathode for aqueous zinc ion battery

引用

Journal of Energy Chemistry 2024年第3期90卷 578-589,I0013页

作者： Yuexin Liu Jian Huang Xiaoyu Li Jiajia Li jinhu yang Kefeng Cai Shanghai Key Laboratory of Development and Application for Metal-Functional Materials Key Laboratory of Advanced Civil Engineering MaterialsMinistry of EducationSchool of Materials Science&EngineeringTongji UniversityShanghai 201804China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201800China Research Center for Translational Medicine East HospitalTongji University School of MedicineShanghai 200092China

The development of aqueous zinc ion battery cathode materials with high capacity and high magnification is still a ***,porous vanadium oxide/carbon(p-VO_(x)@C,mainly VO_(2) with a small amount of V_(2)O_(3)) core/shell microspheres with oxygen vacancies are facilely fabricated by using a vanadium-based metal-organic framework(MIL-100(V)) as a sacrificial *** unique structure can improve the conductivity of the VO_(x),accelerate electrolyte diffusion,and suppress structural collapse during ***,H_(2)O molecules are introduced into the interlayer of VO_(x) through a highly efficient in-situ electrochemical activation process,facilitating the intercalation and diffusion of zinc *** the activation,an optimal sample exhibits a high specific capacity of 464.3 mA h g^(-1) at0.2 A g^(-1) and 395.2 mA h g^(-1) at 10 A g^(-1),indicating excellent rate ***,the optimal sample maintains a capacity retention of about 89.3% after 2500 cycles at 10 A g^(-1).Density functional theory calculation demonstrates that the presence of oxygen vacancies and intercalated water molecules can significantly reduce the diffusion barrier for zinc *** addition,it is proved that the storage of zinc ions in the cathode is achieved by reversible intercalation/extraction during the charge and discharge process through various ex-situ analysis *** work demonstrates that the p-VO_(x)@C has great potential for applications in aqueous ZIBs after electrochemical activation.

关键词： Metal-organic frameworks Vanadium oxide Carbon Zn-ion batteries Electrochemical activation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A New Methodology for Early Detection of Thermoacoustic Combustion Oscillations Based on Permutation Entropy

引用

Journal of Thermal Science 2023年第6期32卷 2310-2320页

作者： LI Yao HU Chunyan SHEN Youhao HAN Bo yang jinhu XU Gang Key Laboratory of Light Duty Gas Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Innovation Academy for Light-Duty Gas Turbine Chinese Academy of SciencesBeijing100190China

We carry out a series of experimental investigations in a model combustor to detect a precursor of thermoacoustic combustion oscillations based on permutation entropy,which can amplify the subtle changes effected in the time sequence to identify the *** changing the flame’s location or the fuel flow to a value,an abrupt switch from aperiodic small-amplitude oscillations to periodic large-amplitude oscillations would occur in pressure *** characteristic frequency of combustion oscillation is obtained by spectral analysis,with which a modified algorithm of the permutation entropy is *** impact evaluation on key parameters such as moving step sizes and window sizes reveals that the moving data permutation entropy has strong robustness,and can accurately detect the onset of thermoacoustic *** nonlinear analysis exhibits peculiar dynamics of the combustion system,which result in specific patterns in the time series and provide a theoretical basis for anomaly *** results suggest that the permutation entropy has a certain potential in early warning and detection of combustion oscillations.

关键词： thermoacoustic combustion oscillation permutation entropy moving data anomaly detection precursors

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Investigation of the Effect of Pilot Burner on Lean Blow Out Performance of A Staged Injector

引用

Journal of Thermal Science 2014年第6期23卷 600-608页

作者： yang jinhu ZHANG Kaiyu LIU Cunxi RUAN Changlong LIU Fuqiang XU Gang Key Laboratory of Light-duty Gas-turbine Institute of Engineering ThermophysicsChinese Academy of Sciences

The staged injector has exhibited great potential to achieve low emissions and is becoming the preferable choice of many civil airplanes. Moreover, it is promising to employ this injector design in military engine, which requires most of the combustion air enters the combustor through injector to reduce smoke emission. However, lean staged injector is prone to combustion instability and extinction in low load operation, so techniques for broadening its stable operation ranges are crucial for its application in real *** this work, the LBO performance of a staged injector is assessed and analyzed on a single sector test *** experiment was done in atmospheric environment with optical access. Kerosene-PLIF technique was used to visualize the spray distribution and common camera was used to record the flame patterns. Emphasis is put on the influence of pilot burner on LBO performance. The fuel to air ratios at LBO of six injectors with different pilot swirler vane angle were evaluated and the obtained LBO data was converted into data at idle condition. Results show that the increase of pilot swirler vane angle could promote the air assisted atomization, which in turn improves the LBO performance slightly. Flame patterns typical in the process of LBO are analyzed and attempts are made to find out the main factors which govern the extinction process with the assistance of spray distribution and numerical flow field results. It can be learned that the flame patterns are mainly influenced by structure of the flow field just behind the pilot burner when the fuel mass flow rate is high; with the reduction of fuel, atomization quality become more and more important and is the main contributing factor of LBO. In the end of the paper,conclusions are drawn and suggestions are made for the optimization of the present staged injector.

关键词： Staged injector LBO Spray distribution Flame pattern

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental Investigation on Ignition and Lean Blow-out Performance of a Multi-sector Centrally Staged Combustor

引用

Journal of Thermal Science 2014年第5期23卷 480-485页

作者： LIU Fuqiang ZHANG Kaiyu MU Yong LIU Cunxi yang jinhu Xu Gang ZHU Junqiang Institute of Engineering Thermophysics Chinese Academy of Science

Improvement on extinction and pollution emission have become one of the most prominent research topics in gas *** is widely recognized that the fuel/air mixture distribution in the recirculation zone is a critical factor in improving lean blow-out(LBO) and *** paper proposed a new low emission scheme with fuel staged centrally and hybrid injector to improve flameout and emission.A relative small amount of fuel enters into central pilot airblast atomizer burner and then atomized by inner swirl *** remaining majority of fuel is directly injected into vane channels of the primary swirler through a series of holes located on the sidewall of the main *** pilot stage is fueled under ignition and lean flameout *** uniformity of fuel/air mixture distribution in the primary zone of the new design decreases NOX emission,meanwhile the fuel air mixture in pilot recirculation zone is locally rich to improve flameout and *** investigation was conducted to compare the new scheme with baseline design of dual-swirler in terms of LBO and ignition characteristics under the same condition in a multi-sector *** is found that the fuel-air ratio of ignition limit and LBO decrease with the reference velocity *** experimental results also show that the new scheme successfully improve lean blow-out and broaden the operation range of the *** experimental results indicated that the centrally staged scheme can widen the operation boundary of the combustor and can provide guidance for design and optimization of combustion chamber.

关键词： Ignition Lean blow-out Staged combustor Pilot stage Fuel air ratio

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Armoring Black Phosphorus Anode with Stable Metal–Organic‑Framework Layer for Hybrid K‑Ion Capacitors

引用

Nano-Micro Letters 2021年第3期13卷 9-21页

作者： Mengzhu Xu Yutong Feng Bingjie Chen Ruijin Meng Mengting Xia Feng Gu Donglei yang Chi Zhang jinhu yang Research Center for Translational Medicine&Key Laboratory of Arrhythmias of the Ministry of Education of China East HospitalTongji University School of MedicineShanghai 200120People’s Republic of China School of Chemical Science and Engineering Tongji UniversityShanghai 200092People’s Republic of China Institute for Process Modelling and Optimization Jiangsu Industrial Technology Research InstituteSIP388 Ruoshui RoadSuzhouJiangsuPeople’s Republic of China Institute of Molecular Medicine School of Medicine Shanghai Jiao Tong UniversityShanghai 200127People’s Republic of China

Potassium-ion capacitors(KICs)are promising for sustainable and eco-friendly energy storage technologies,yet their slow reaction kinetics and poor cyclability induced by large K-ion size are a major obstacle toward practical ***,by employing black phosphorus nanosheets(BPNSs)as a typical high-capacity anode material,we report that BPNS anodes armored with an ultrathin oriented-grown metal–organic-framework(MOF)interphase layer(BPNS@MOF)exhibit regulated potassium storage behavior for highperformance *** MOF interphase layers as protective layer with ordered pores and high chemical/mechanical stability facilitate K ion diffusion and accommodate the volume change of electrode,beneficial for improved reaction kinetics and enhanced cyclability,as evidenced by substantial characterizations,kinetics analysis and DFT ***,the BPNS@MOF electrode as KIC anodes exhibits outstanding cycle performance outperforming most of the reported state-of-art KICs so far.

关键词： Black phosphorus MOF Interphase engineering Potassium-ion capacitor Cycling stability

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Metamagnetic transitions and anomalous magnetoresistance in EuAg4As2 crystals

引用

Science China(Physics,Mechanics & Astronomy) 2021年第2期64卷 91-97页

作者： QinQing Zhu Liang Li ZhiHua yang ZheFeng Lou JianHua Du jinhu yang Bin Chen HangDong Wang MingHu Fang Hangzhou Key Laboratory of Quantum Matter Department of PhysicsHangzhou Normal UniversityHangzhou311121China Department of Physics Zhejiang UniversityHangzhou310027China Department of Physics China Jiliang UniversityHangzhou310018China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing210093China

In this work,we systematically studied the magnetic and transport properties of EuAg4As2 single *** was found that the two antiferromagnetic transitions(TN1=10 K and TN2=15 K)were driven to lower temperatures by an applied magnetic *** TN1,two successive metamagnetic transitions were observed when a magnetic field was applied in the ab plane(H//abplane).For both H//ab and H//c,EuAg4As2 showed a positive,unexpectedly large magnetoresistance(up to 202%)in lower magnetic fields below TN1,and a large negative magnetoresistance(up to-78%)at high fields/intermediate temperatures,thus presenting potential applications in magnetic ***,the magnetic phase diagrams of EuAg4As2 were constructed for both H//ab and H//c using the resistivity and magnetisation data.

关键词： anomalous magnetoresistance metamagnetic transition magnetic phase diagram

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Changes in terrestrial surface dry and wet conditions on the Loess Plateau(China) during the last half century

引用

Journal of Arid Land 2013年第1期5卷 15-24页

作者： YuBi YAO RunYuan WANG jinhu yang Ping YUE DengRong LU Guo,Ju XIAO yang WANG LinChun LIU China Meteorological Administration Key Laboratory of Arid Climate Change and Reducing Disaster Lanzhou 730020 China Gansu Province Key Laboratory of Arid Climate Change and Reducing Disaster Lanzhou 730020 China Lanzhou Institute of'Arid Meteorology China Meteorological Administration Lanzhou 730020 China Meteorological Bureau of Dingxi City Dingxi 743000 China Gansu Meteorological Information Center Lanzhou 730020 China New Technology Application Research and Development Centre of Ningxia University Yinchuan 750021 China

This paper, using a revised Penman-Monteith model, computed the terrestrial surface humidity index of the Loess Plateau （China） based on climatic factors of monthly mean temperature, maximum temperature, minimum temperature, relative humidity, precipitation, wind speed and sunshine duration observed on the plateau from 1961 to 2008. The temporal-spatial distribution, anomaly distribution and sub-regional temporal variations of the terrestrial surface dry and wet conditions were analyzed as well. The results showed a decreasing trend in the annual average surface humidity from the southeast to the northwest in the research anna. Over the period of 1961-2008, an aridification tendency appeared sharply in the central interior region of the Loess Plateau, and less sharply in the middle part of the region. The border region showed the weakest tendency ol; aridification. It is clear that aridification diffused in all directions from the interior region. The spatial anomaly distribution of the terrestrial surface dry and wet conditions on the Loess Plateau can be divided into three key areas： the southern, western and eastern regions. The terrestrial annual humidity index displayed a significantly descending trend and showed remarkable abrupt changes from wet to dry in the years 1967, 1977 and 1979. In the above mentioned three key areas for dry and wet conditions, the terrestrial annual humidity index exhibited a fluctuation period of 3-4 years, while in the southern region, a fluctuation period of 7-8 years existed at the same time.

关键词： dry and wet conditions spatial distribution temporal variation Penman-Monteith model Loess Plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：