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On entire solutions of some Fermat type differential-difference equations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 69-88页

作者： LONG Jian-ren QIN Da-zhuan School of Mathematical Sciences Guizhou Normal UniversityGuiyang 550025China

On one hand,we study the existence of transcendental entire solutions with finite order of the Fermat type difference *** the other hand,we also investigate the existence and growth of solutions of nonlinear different... 详细信息

关键词： entire solutions differential-difference equations existence finite order

Incremental cost analysis model of distribution network based on economic dispatch of distributed new-energy storage system

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Clean Energy 2024年第2期8卷 89-103页

作者： zhuan Zhou Jiayu Bian Zhiyong Yu State Grid Xinjiang Electric Power Co. ltdXinjiangChina

With the implementation of China’s carbon-peaking and carbon-neutrality strategy,new energy will achieve leapfrog *** to the good economics of distributed new-energy generation,it can not only save users’own investment,but also help to achieve local consumption of new ***,it will also bring about a series of incremental costs to the power *** paper first enumerates the concept,development status and scheduling mode of a distributed new-energy storage *** on the above,it establishes a new-energy power generation model and an energy storage system charging and discharging model,and proposes a global optimization scheduling model for a distributed new-energy storage system,considering the time-of-use electricity price and taking the lowest total operating cost of the distributed new-energy power generation system as the objective ***,it proposes a distribution network incremental cost analysis model based on the penetration of distributed new *** calculation results show that the incremental cost of grid-connected distributed new energy is 1.0849,1.2585 and 1.3473 yuan/kWh,respectively,which indicates that the global dispatching model can optimize the power consumption structure of a distributed power generation system,and has the function of peak shaving and valley filling,but the incremental cost of the distribution network will also increase.

关键词： distributed new energy electrochemical energy storage economic dispatch distribution network cost time-sharing price

Ammonia Volatilization and Deriitrification Losses from an Irrigated Maize-Wheat Rotation Field in the North China Plain

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Pedosphere 2004年第4期14卷 533-540页

作者： ZHANGYu-Ming CHENDe-Li ZHANGJia-Bao R.EDIS HUChun-Sheng zhuan-ning InstituteofGeneticsandDevelopmentalBiology ChineseAcademyofSciencesShijiazhuang050021（China） DepartmentofResourceManagementandHorticulture InstituteofLandandFoodResourcetheUniversityofMel-bourneParkville3052Victoria（Australia） InstituteofSoilScience ChineseAcademyofSciencesNanjing210008（China）

Ammonia (NH3) volatilization, denitrification loss, and nitrous oxide (N2O) emission were investigated from an irrigated wheat-maize rotation field on the North China Plain, and the magnitude of gaseous N loss from denitrification and NH3 volatilization was assessed. The micrometeorological gradient diffusion method in conjunction with a Bowen Ratio system was utilized to measure actual NH3 fluxes over a large area, while the acetylene inhibition technique (intact soil cores) was employed for measurement of denitrification losses and N2O emissions. Ammonia volatilization loss was 26.62% of the applied fertilizer nitrogen (N) under maize, while 0.90% and 15.55% were lost from the wheat field at sowing and topdressing, respectively. The differences in NH3 volatilization between different measurement events may be due to differences between the fertilization methods, and to differences in climatic conditions such as soil *** losses in the fertilized plots were 0.67%-2.87% and 0.31%-0.49% of the applied fertilizer N under maize and wheat after subtracting those of the controls, respectively. Nitrous oxide emissions in the fertilized plots were approximately 0.08%-0.41% and 0.26%-0.34% of the applied fertilizer N over the maize and wheat seasons after subtracting those of the controls, correspondingly. The fertilizer N losses due to NH3 volatilization were markedly higher than those through denitrification and nitrous oxide emissions. These results indicated that NH3 volatilization was an important N transformation in the crop-soil system and was likely to be the major cause of low efficiencies with N fertilizer in the study area. Denitrification was not a very important pathway of N fertilizer loss, but did result in important evolution of the greenhouse gas N2O and the effect of N2O emitted from agricultural fields on environment should not be overlooked.

关键词： ammonia volatilization denitrification gaseous N loss N_2O emission

Electro-spraying/spinning: A novel battery manufacturing technology

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Green Energy & Environment 2024年第1期9卷 81-88页

作者： zhuan Hu Jiaxin Hao Dongyang Shen Caitian Gao Zhaomeng Liu Jianguo Zhao Bingan Lu School of Physics and Electronics Hunan UniversityChangsha410082China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan Provincial Key Laboratory of Multi-electron Based Energy Storage DevicesHunan UniversityChangsha410082China School of Physics and Electronic Information Luoyang Normal UniversityLuoyang471934China Section of Environmental Protection Key Laboratory of Eco-Industry School of MetallurgyNortheastern UniversityShenyangLiaoning110819China

Lithium-ion battery(LIB) industry seems to have met its bottle neck in cutting down producing costs even though much efforts have been put into building a complete industrial chain. Actually, manufacturing methods can greatly affect the cost of battery production. Up to now, lithium ion battery producers still adopt manufacturing methods with cumbersome sub-components preparing processes and costly assembling procedures, which will undoubtedly elevate the producing cost. Herein, we propose a novel approach to directly assemble battery components(cathode, anode and separator) in an integrated way using electro-spraying and electro-spinning technologies. More importantly, this novel battery manufacturing method can produce LIBs in large scale, and the products show excellent mechanical strength, flexibility, thermal stability and electrolyte wettability. Additionally, the performance of the as-prepaed Li Fe PO_(4)||graphite full cell produced by this new method is comparable or even better than that produced by conventional manufacturing approach. In brief, this work provides a new promising technology to prepare LIBs with low cost and better performance.

关键词： Electro-spraying Electro-spinning Integrated electrode Lithium-ion battery

1,3-Dipolar Cycloaddition of Polycyclic Aromatic Azomethine Ylides and Alkynylbenziodoxoles for Synthesis of Functional Dibenzoullazines

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Chinese Journal of Chemistry 2024年第10期42卷 1079-1083页

作者： Hui Han Glen Wee zhuan Goh Yongxin Li Naohiko Yoshikai Shingo Ito Schoolof Chemistry ChemicalEngineering and BiotechnologyNanyang Technoogical University21 Nanyang LinkSingapore 637371Singapore Graduate School of Pharmaceutical Sciences Tohoku UniversitySendai 980-8578Japan

A new family of dibenzoullazine derivatives was synthesized through 1,3-dipolar cycloaddition of polycyclic aromatic azomethine ylides with alkynylbenziodoxoles followed by *** benziodoxole moiety in the resulting products was used as a versatile linchpin for the synthesis of structurally diverse functional dibenzoullazines that are difficult to access by other synthetic methods.

关键词： Cycloaddition Nitrogen heterocycles Azomethine ylides Hypervalent compounds Dibenzoullazine

Burden of gastrointestinal cancers among working-age population over past thirty years in China

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World Journal of Gastrointestinal Oncology 2024年第9期16卷 3955-3979页

作者： Yu Dong zhuan-zhuan Fan Wen-Ting Li Jian Kang Yan Zhang Yue Guan Hui-Qing Xu Jie Yuan Fei Xu Department of Gastroenterology Nanjing First HospitalNanjing Medical UniversityNanjing 210006Jiangsu ProvinceChina Department of Primary Healthcare Management Nanjing Municipal Center for Disease Control and PreventionNanjing 210003Jiangsu ProvinceChina Department of Emergency The First Affiliated Hospital with Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina Department of Epidemiology Nanjing Medical University School of Public HealthNanjing 211116Jiangsu ProvinceChina

BACKGROUND Although gastrointestinal(GI)cancers have been becoming a great public health concern in China,there is currently a lack of comprehensive literature on the overall burden and changing trends of GI cancers in the working-age *** To assess the burden of GI cancers and to examine the overall,age-and genderspecific trends among the working-age population in China from 1990 to *** Data were extracted from the Global Burden of Disease Study *** burden of GI cancers was indicated by incidence,mortality,disability-adjusted life-years(DALYs),age-standardized incidence rate(ASIR),age-standardized mortality rate,and age-standardized DALYs *** in the burden of GI cancers from 1990 to 2019 were examined using annual percent change and average annual percent change with Joinpoint regression *** For overall GI cancers,a declining trend was observed in the ASIR,age-standardized mortality rate,and agestandardized DALYs rate,with reductions of 0.74%,2.23%,and 2.22%,respectively,from 1999 to 2019 in the Chinese working-age ***,an increasing trend was observed in the ASIR for overall GI cancers from *** number of either incident cases,mortality cases,and DALYs was higher for colon/rectum cancer and liver cancer in younger participants but lower for esophageal,gallbladder,biliary tract,pancreatic,and stomach cancer among older ***,sex disparity in the GI cancers burden was also examined over 30 *** The total burden of GI cancers remained heavy among the working-age population in China,although declining trends were observed from 1999 to *** in the GI cancers burden existed between sexes,age groups,and cancer ***-based precision prevention strategies are needed to tackle GI cancers among working-age individuals,considering the age,sex,and cancer type disparities in China.

关键词： Gastrointestinal cancer Working-age population Disease burden Disability-adjusted life-years Chinese

Autonomous Recommendation of Fault Detection Algorithms for Spacecraft

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 273-275页

作者： Wenbo Li Baoling ning the National Key Laboratory of Science and Technology on Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100094China the School of Data Science and Technology Heilongjiang UniversityHarbin 150001China

Dear Editor, This letter deals with the problem of algorithm recommendation for online fault detection of spacecraft. By transforming the time series data into distributions and introducing a distribution-aware measure, a principal method is designed for quantifying the detectabilities of fault detection algorithms over special datasets.

关键词： fault introducing letter

Performance enhancement of perovskite solar cells:surface is the key

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Science China Materials 2024年第1期67卷 375-376页

作者： Wenzhuo Li Zhijun ning School of Physical Science and Technology Shanghaitech UniversityShanghai 201210China

Metal halide perovskite solar cells(PSCs)stand out as one of the most promising contenders among photovoltaic technologies for the *** the past decade,PSCs with high power conversion efficiency(PCE)predominantly adopted the normal(ni-p)device ***,a common p-type organic small molecule,Spiro-OMe TAD,which is widely employed at the top layer of n-i-p devices[1],faces issues such as susceptibility to water absorption and poor thermal stability.

关键词： structure stability perovskite

Impact of non-ideal UE hardware on cell-free massive MIMO network with centralized operation

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Science China(Information Sciences) 2024年第4期67卷 255-271页

作者： ning LI Pingzhi FAN Institute of Mobile Communications Southwest Jiaotong University

This paper investigates the impact of non-ideal user equipment(UE) hardware on a cell-free(CF) massive MIMO(mMIMO) network with centralized operation under spatially correlated channels. The minimum mean-squared error(MMSE) estimator can be derived with the help of the generic non-ideal UE hardware model. It is demonstrated that even if the effective signal-to-noise ratio approaches infinity, pilot contamination and imperfect hardware can cause a non-zero estimation error floor. After that, a lower bound is determined for the ergodic uplink capacity of the centralized CF mMIMO network under non-ideal UE hardware. Moreover, the optimal receive combining vector is obtained to maximize the uplink spectral efficiency(SE). The maximum ratio(MR) and regularized zero-forcing(RZF) combining schemes are offered as alternatives in light of the computational complexity of the MMSE receiver. Comparing the RZF to the MMSE scheme under different levels of hardware impairments, our findings indicate that the RZF receiver suffers a negligible loss in total SE. For MR combining, a novel closed-form uplink achievable SE expression is obtained based on the MMSE estimator and the use-and-then-forget bounding technique. This expression gives vital insights into the achievable uplink performance with UE hardware impairments. Besides, for various hardware impairment factors, the impact of pilot sequence length on average sum SE is disclosed for different receive combining schemes. To increase the overall SE of the max-min fairness scheme, a heuristic fractional power control scheme with UE hardware impairments is developed, which can essentially avoid sacrificing the SE of other UEs while maximizing the SE of the unluckiest UE in the whole network. Finally,our theoretical performance analysis and power control algorithm are validated by simulation results, and fundamental design guidelines are provided for selecting hardware satisfying the practical UE requirements.

关键词： cell-free massive MIMO centralized operation spatially correlated channels hardware impairments channel estimation uplink spectral efficiency optimal receive combining pilot length design fractional power control