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富镍双金属催化剂的制备及其对复合藻基原料共水热催化性能研究

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工程热物理学报 2024年第2期45卷 605-613页

作者：胡亚敏张文珏闫佳玮王爽曹斌袁川钱黎黎王谦江苏大学能源与动力工程学院镇江212013

该文开展了大藻与微藻共水热催化制备生物油研究,考察了Ni-Mo/MCM-41和Ni-W/MCM-41催化剂对生物油产率和组分分布的作用特性。结果表明,双金属催化剂会降低复合藻基原料水热生物油的产率,但发挥了一定的加氢脱氮效果,提高了油相产物中... 详细信息

该文开展了大藻与微藻共水热催化制备生物油研究,考察了Ni-Mo/MCM-41和Ni-W/MCM-41催化剂对生物油产率和组分分布的作用特性。结果表明,双金属催化剂会降低复合藻基原料水热生物油的产率,但发挥了一定的加氢脱氮效果,提高了油相产物中烃类物质含量(最多提高33.04%),并降低了含氮化合物含量(最多降低38.88%)和氧含量,有效改善了生物油的品质。此外,采用扫描电镜、X射线衍射、X射线光电子能谱和氨气吸脱附研究了Ni-Mo/MCM-41和Ni-W/MCM-41催化剂的物理化学性质。

关键词：生物油双金属催化剂共水热液化 MCM-41

生鲜农产品冷链物流发展现状与优化策略研究——以徐州市为例

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物流科技 2024年第9期47卷 167-169页

作者：王佳乐胡亚敏江苏师范大学商学院江苏徐州221226

近年来,随着乡村振兴的深入和生鲜电商的飞速发展,生鲜农产品的市场需求量日益扩大,给冷链物流业的发展带来了新的机遇和挑战,优化生鲜农产品冷链物流的发展逐渐成为实务界和理论界聚焦的问题。文章以淮海经济区农业大市——徐州市为研... 详细信息

近年来,随着乡村振兴的深入和生鲜电商的飞速发展,生鲜农产品的市场需求量日益扩大,给冷链物流业的发展带来了新的机遇和挑战,优化生鲜农产品冷链物流的发展逐渐成为实务界和理论界聚焦的问题。文章以淮海经济区农业大市——徐州市为研究对象,实际分析徐州市生鲜农产品冷链物流的发展条件和发展现状,讨论冷链物流实际需求与发展现状的矛盾,并提出了针对性优化发展建议,旨在推动徐州市生鲜农产品冷链物流的高质量发展。

关键词：冷链物流生鲜农产品徐州市

桑克模式下物流企业战略成本管理研究——以SF为例

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物流科技 2024年第18期47卷 138-142页

作者：戚妍君胡亚敏江苏师范大学商学院江苏徐州221100

政策的支持以及电商经济的兴起推动了物流行业的进一步发展,目前物流行业竞争激烈,想要在市场上占据一席之地就要对成本进行管控,但传统的成本管理模式已经不能适应时代需求,为了更好地对成本进行管控,应将成本管理上升到战略层面,从而... 详细信息

政策的支持以及电商经济的兴起推动了物流行业的进一步发展,目前物流行业竞争激烈,想要在市场上占据一席之地就要对成本进行管控,但传统的成本管理模式已经不能适应时代需求,为了更好地对成本进行管控,应将成本管理上升到战略层面,从而提升企业的核心竞争力。文章以SF为例,在分析其目前战略成本管理运用现状的基础上,从战略定位分析、成本动因分析及价值链分析三个角度对其战略成本管理进行深入的分析,探究SF目前成本管理存在的问题,并提出优化建议。

关键词：桑克模式战略成本管理战略定位分析成本动因分析价值链分析

IEC Before and After the QoCExperiment:Nong'an,Jilin

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China Population Today 1999年第Z2期16卷 17-18页

作者： hu yamin

This article presents the Quality of Care (QoC) program and the impact it had on the information, education and communication (IEC) program in Jilin, Nong'an. Prior to the implementation of the QoC, the IEC program in the province focused on government regulation and demographic conditions rather than people's reproductive rights and health care needs. A survey conducted in the province revealed that the majority of local women were not aware of the need to take contraceptive measures during breastfeeding and to remove IUD upon menopause. This indicates that the IEC program had not been popular in the province. However, since the initiation of the QoC program in 1995, a client-centered approach has been widely adopted by family planning workers. This approach integrates contraception with reproductive health; some of the practices include information dissemination, mobilizing IEC teams to reach out to villagers, workshops for IEC promoters, and organized home visits. In addition, the IEC program has broadened people's knowledge base about various contraceptive methods. People have become more conscious of their reproductive health and attitudes towards marriage and childbearing have changed.

关键词： IEC Before and After the QoCExperiment

Disastrous Persistent Extreme Rainfall Events of the 2022 Pre-Flood Season in South China:Causes and Subseasonal Predictions

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Journal of Meteorological Research 2023年第4期37卷 469-485页

作者： Jiehong XIE Pang-Chi HSU yamin hu Qiaomei LIN Mengxi YE Key Laboratory of Meteorological Disaster of Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210000 Jieyang Meteorological Bureau China Meteorological AdministrationJieyang 522000 Guangdong Climate Center China Meteorological AdministrationGuangzhou 510000

Two persistent extreme rainfall events(PEREs) with record-breaking amounts of rainfall and long duration caused disastrous impact during the 2022 pre-flood season in South China. Atmospheric intraseasonal variability played a key role in triggering and maintaining both PEREs, but its major impact on each event was associated with different modes. For the first PERE(10-15 May;PERE1), the tropical and extratropical quasi-biweekly oscillations jointly contributed to the extreme rainfall intensity. In contrast, the long duration(6-21 June) of the heavy rainfall during the second PERE(PERE2) was closely related to prolonged convection and moisture transport anomalies induced mainly by the tropical 30-90-day variability. Subseasonal-to-seasonal predictions by the model of the ECMWF showed limited skill in relation to the rainfall intensity of PERE1 and PERE2 beyond 1–2 weeks. Further assessment suggested that the fidelity of the PERE predictions was linked to model skill in predicting the phase evolution and intensity of tropical and extratropical intraseasonal variabilities. Thus, efficient monitoring and accurate prediction of the various modes of atmospheric intraseasonal variability are fundamental to reducing the hazard associated with PEREs in South China.

关键词： persistent extreme rainfall event intraseasonal oscillation South China subseasonal-to-seasonal prediction

Predictor Selection for CNN-based Statistical Downscaling of Monthly Precipitation

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Advances in Atmospheric Sciences 2023年第6期40卷 1117-1131页

作者： Dangfu YANG Shengjun LIU yamin hu Xinru LIU Jiehong XIE Liang ZHAO Central South University Changsha 410083China Guangdong Climate Center Guangzhou 510610China Jieyang Meteorological Bureau Jieyang 522031China State Key Laboratory of Numerical Modeling for Atmosphere Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Convolutional neural networks(CNNs) have been widely studied and found to obtain favorable results in statistical downscaling to derive high-resolution climate variables from large-scale coarse general circulation models(GCMs).However, there is a lack of research exploring the predictor selection for CNN modeling. This paper presents an effective and efficient greedy elimination algorithm to address this problem. The algorithm has three main steps: predictor importance attribution, predictor removal, and CNN retraining, which are performed sequentially and iteratively. The importance of individual predictors is measured by a gradient-based importance metric computed by a CNN backpropagation technique, which was initially proposed for CNN interpretation. The algorithm is tested on the CNN-based statistical downscaling of monthly precipitation with 20 candidate predictors and compared with a correlation analysisbased approach. Linear models are implemented as benchmarks. The experiments illustrate that the predictor selection solution can reduce the number of input predictors by more than half, improve the accuracy of both linear and CNN models,and outperform the correlation analysis method. Although the RMSE(root-mean-square error) is reduced by only 0.8%,only 9 out of 20 predictors are used to build the CNN, and the FLOPs(Floating Point Operations) decrease by 20.4%. The results imply that the algorithm can find subset predictors that correlate more to the monthly precipitation of the target area and seasons in a nonlinear way. It is worth mentioning that the algorithm is compatible with other CNN models with stacked variables as input and has the potential for nonlinear correlation predictor selection.

关键词： predictor selection convolutional neural network statistical downscaling gradient-based importance metric

1995—2021年广东“龙舟水”期间灾情分析

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气象科技 2024年第3期52卷 415-423页

作者：姜晓岑胡娅敏黄锋莫伟强广东省东莞市气象局东莞523082 广东省气候中心广州510640

针对广东“龙舟水”灾情的灾前预估和灾后快速估计的需求,本文利用1995—2021年广东“龙舟水”期间降雨和暴雨洪涝灾害数据,计算“龙舟水”综合灾情指数,应用百分位法将其划分为轻、中、重3个等级;并对广东“龙舟水”的灾情特征、降雨... 详细信息

针对广东“龙舟水”灾情的灾前预估和灾后快速估计的需求,本文利用1995—2021年广东“龙舟水”期间降雨和暴雨洪涝灾害数据,计算“龙舟水”综合灾情指数,应用百分位法将其划分为轻、中、重3个等级;并对广东“龙舟水”的灾情特征、降雨与灾情的关系进行分析。结果表明:(1)1995—2021年广东“龙舟水”期间降雨强度、范围、强降雨频率及持续时间的峰值集中在2005—2010年,灾情强峰值出现在2005—2008年,峰值区间较一致;2008年灾情最重,2008年后综合灾情强度呈下降趋势,近10 a(2012—2021年)各灾情也呈下降趋势,以倒塌房屋数、受灾人口数、农作物受灾面积降幅最明显,直接经济损失降幅较小。(2)农作物受灾面积与各降雨指标的相关性最大,其次为受灾人口数和直接经济损失;综合灾情等级、直接经济损失主要受降雨强度、强降雨频率影响,受灾人口数、农作物受灾面积灾情主要受降雨强度、降雨范围影响,倒塌房屋数、死亡人数灾情主要受强降雨的频率影响。(3)建立的“龙舟水”平均总降雨量与灾情的拟合关系方程,能较好地估计“龙舟水”综合灾情等级和灾情数据。

关键词：龙舟水灾情特征分析灾情估计

Numerical study of atmospheric-pressure argon plasma jet propagating into ambient nitrogen

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Plasma Science and Technology 2022年第5期24卷 17-28页

作者： Yuanyuan JIANG Yanhui WANG yamin hu Jiao ZHANG Dezhen WANG Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024People’s Republic of China

A 2D axial symmetry fluid model is applied to study the features of an atmospheric-pressure argon(Ar) plasma jet propagating into ambient nitrogen(N_(2)) driven by a pulsed voltage,emphasizing the influence of gas velocity on the dynamic characteristics of the jet. The results show that the Ar jet exhibits a cylindrical-shaped channel and the jet channel gradually shrinks with the increase in propagation length. The jet propagation velocity varies with time. Inside the dielectric tube, the plasma jet accelerates propagation and reaches its maximum value near the nozzle. Exiting the tube, its velocity quickly decreases and when approaching the metal plane,the decrease in jet velocity slows down. The increase in gas speed results in the variation of jet spatial distribution. The electron density presents a solid structure at lower gas flow speeds,whereas an annular structure can be observed under the higher gas flow velocity in the ionization head. The jet length increases with the flow velocity. However, when the flow velocity exceeds a critical value, the increase in the rate of the plasma jet length slows down. In addition, the gas velocity effect on the generation and transport of the reactive particles is also studied and discussed.

关键词： atmospheric-pressure argon plasma jet gas flow velocity 2D simulation propagation characteristics reactive species

Study on Preparation of Nitrogen-Doped Hierarchically Porous and High-Performance Carbon Materials from Seaweed Biomass

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Journal of Renewable Materials 2022年第2期10卷 541-560页

作者： Kaihan Xie yamin hu Stephen Afonaa-Mensah Chuan Yuan Bin Cao Shuang Wang Qian Wang School of Energy and Power Engineering Jiangsu UniversityZhenjiangChina Takoradi Technical University TakoradiGhana

Use Enteromorpha clathrate as a carbon and nitrogen precursor could obtain the N-doped porous carbon mate-rials by two-step *** this paper,the exogenous nitrogen(urea,melamine)and activating agents(KOH,ZnCl_(2))were employed for the production of higher-performance carbon materials from seaweed ***,BET,FTIR,XRD,XPS,Raman and ultimate analyses were carried out to investigate the morpho-structural and elemental peculiarities of the carbonaceous ***,cyclic voltammetry(CV),galvanostatic charge-discharge(GCD)and cyclic charge-discharge tests were carried out to examine the electrochemical properties of the *** results showed that electrochemical performance of the carbonaceous materials improved by adding the appropriate nitrogen *** improvement was observed under either condition,when the nitro-gen source and activating agent were melamine and ZnCl_(2) or urea and KOH,***,under the condition with KOH as the activator,the nitrogen content of carbon material without exogenous nitrogen was initially 1.46%.After the addition of urea or melamine,the nitrogen content increased to 4.86%and 6.18%,*** the condition with ZnCl_(2) as the activator,and without exogenous nitrogen,the nitrogen con-tent of carbon materials was initially 3.75%.However,after adding urea or melamine,the nitrogen content increased to 12.11%and 14.76%,*** carbonaceous materials(prepared from urea/KOH and mel-amine/ZnCl_(2))showed excellent gravimetric capacitances of 172 and 151.5 F/g at 1A/***,at a current density of 5 A/g,their specific capacitance retention rate reached 78.3%and 82.6%respectively after 1000 cycles.

关键词： Exogenous nitrogen incorporation N-doped porous carbon two-steps pyrolysis enteromorpha clathrate