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Preparation and Properties of Fiber Optic Oxygen Sensing Material by Thermo-polymerization Method

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Journal of Wuhan University of Technology(Materials Science) 2008年第2期23卷 225-229页

作者： zhang tianhua CHEN Xing HUANG Jun Hospital Wuhan University of Technology Wuhan 430070 China Fiber Optic Sensing Technology Research Center Wuhan University of Technology Wuhan 430070 China

A new kind of fiber optic oxygen sensing material based on the fluorescence quenching of Ru（bpy）3Cl2 was prepared by the themo-polymerization method. The ruthenium dye was immobilized in N, N-methylene bisacrylamide（MBBA） polymer by physically trapping while MBBA was covalently crosslinked on the glass micro-beads by NaHSO3-O2-MnSO4 initiator system. The lock-in amplifyication technology was used for the detection of their sensing properties. The influences of indicator concentration, glass micro-beads diameter, post polymerization time, concentration and reaction time of glutaraldehyde on the properties of sensing materials were studied. To optimize the influencing factors to the sensing materials, the indicator concentration of 0.7 g/L, glass micro-beads diameter of 0.3 mm, post polymerization time of 5 h were achieved. The immobilization stability of ruthenium dye and the performance of the sensing materials were improved by the new polymerization system. An absolute detection limit of 3×10-6 （V/V） and the response time of 10 s were obtained. This kind of sensing materials has good stability and their life time is 2 years.

关键词： thermo-polymerization fiber optic sensing materials stability

An Approximation of the Customer Waiting Time for Online Restaurants Owning Delivery System

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Journal of Systems Science & Complexity 2019年第3期32卷 907-931页

作者： zhang tianhua ZHAO Fu zhang Juliang MENDIS Gamini RU Yihong SUTHERLADN John W School of Economics and Management Beijing Jiaotong University Beijing 100010 China School of Mechanical Engineering Purdue University West Lafayette IN 47907-2088 USA Division of Environmental and Ecological Engineering Purdue University West Lafayette IN 47907-2088 USA

Online restaurants, which receive online orders and deliver food directly to the customer’s residence, are becoming increasingly popular. To be successful, online restaurants need to provide reliable and prompt deliveries. Careful design of the meal preparation and order delivery systems is needed to avoid excessive cust omer waiting time bet ween ordering and delivery. This paper considers the meal preparation and delivery processes simultaneously to approximate average customer waiting time for deliveries. The authors first discuss the system performance with one cook and unit-capacity delivery vehicles, using an M/G/1queue and a GI/G/1queue. Numerical experiments show that our approximation can adequately describe real waiting times. Then, series queues with multiple cooks and multi-capacity delivery vehicles, e.g., an M/G/n queue and a GI/Gn/1 queue, are examined. Results show that except for situations with a large meal preparation time and a small vehicle capacity, compared with the result of simulation, the approximation in this paper is acceptable with a deviation of less than 20%. The marginal decrease in waiting time associated with hiring more vehicles is *** under different meal preparation speeds, sizes of service area and vehicle capacities.

关键词： Delivery electronic commerce last mile problem online restaurant queuing theory

Waste heat recovery from hot steel slag on the production line:Numerical simulation,validation and industrial test

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International Journal of Minerals,Metallurgy and Materials 2023年第11期30卷 2191-2199页

作者： tianhua zhang Longheng Xiao Guibo Qiu Huigang Wang Min Guo Xiangtao Huo Mei zhang State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China Central Research Institute of Building and Construction Co. Ltd.MCC GroupBeijing 100088China

Waste heat recovery from hot steel slag was determined in a granular bed through the combination of numerical simulation and an industrial test ***,the effective thermal conductivity of the granular bed was ***,the unsteady-state model was used to simulate the heat recovery under three different flow fields(O-type,S-type,and nonshielding type(Nontype)).Second,the simulation results were validated by in-situ industrial *** two methods confirmed that the heat recovery efficiencies of the flow fields from high to low followed the order of Nontype,S-type,and ***,heat recovery was carried out under the Nontype flow field in an industrial *** heat recovery efficiency increased from~76%and~78%to~81%when the steel slag thickness decreased from 400 and 300 to 200 mm,corresponding to reductions in the steel slag mass from 3.96 and 2.97 to 1.98 t with a blower air volume of 14687 m^(3)/***,the research results showed that numerical simulation can not only guide experiments on waste heat recovery but also optimize the flow *** importantly,the method proposed in this paper has achieved higher waste heat recovery from hot steel slag in industrial scale.

关键词： hot steel slag calculation and verification industrial tests waste heat recovery

Review on catalytic roles of rare earth elements in ammonia synthesis:Development and perspective

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Journal of Rare Earths 2022年第1期40卷 1-10页

作者： Lingling Li tianhua zhang Yanliang Zhou Xiuyun Wang Chak-tong Au Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002China

Ammonia(NH3)is mainly produced via the Haber-Bosch *** was discovered that the performance of a wide variety of catalysts in NH3 synthesis could be considerably enhanced by the addition of rare earth elements(REEs).As a result,catalysts promoted by REEs,especially the Ru-based ones have been extensively *** this review,we summarize the progress of utilizing REEs for ammonia synthesis and outline the prospects of using them in the design and development of highly efficient and stable catalysts for ammonia synthesis.

关键词： Ammonia synthesis catalyst Rare earth elements Thermal catalytic process Catalytic role Sustainable routes

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Spread-F的经度效应

北京大学学报（自然科学版） 2001年第3期37卷 348-352页

作者：张天华肖佐北京大学地球物理学系北京100871

从三维地理坐标系出发建立模型 ,考虑了地磁倾角和偏角的影响 ,研究Spread F现象的全球分布特点 ,是对以前的研究从赤道地区向中、低纬度地区的推广。从该三维模型中可以看到地磁场的大小和位型的影响 (包括磁倾角和磁偏角的效应 )。由... 详细信息

从三维地理坐标系出发建立模型 ,考虑了地磁倾角和偏角的影响 ,研究Spread F现象的全球分布特点 ,是对以前的研究从赤道地区向中、低纬度地区的推广。从该三维模型中可以看到地磁场的大小和位型的影响 (包括磁倾角和磁偏角的效应 )。由于地磁位型的不同 ,发生率的分布并不具有经度对称性 ,即使在磁赤道附近也如此。在某些特殊的经度和纬度地区 ,会达到发生率的峰值。

关键词： Spread-F 三维地理坐标系经度效应地磁效应电离层风

Boosting Efficient Ammonia Synthesis over Atomically Dispersed Co-Based Catalyst via the Modulation of Geometric and Electronic Structures

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CCS Chemistry 2022年第5期4卷 1758-1769页

作者： Yanliang Zhou Congying Wang Xuanbei Peng tianhua zhang Xiuyun Wang Yafei Jiang Haifeng Qi Lirong Zheng Jianxin Lin Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhouFujian 350002 Department of Chemistry Southern University of Science and TechnologyShenzhen 518055 Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023 Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049

Ammonia(NH_(3))synthesis at mild conditions is of great significance,while the significant bottleneck of this process is the activation of N_(2) to realize the desired NH_(3) synthesis performance,which requires deep insight and rational design of active sites at the atomic ***,were synthesized atomically dispersed Co-based catalysts with different Co-N coordination numbers(CNs)to explore the coordination-sensitive NH_(3) synthesis reaction for the first *** studies showed that Co-based catalysts increased the NH_(3) synthesis rate gradually with a decrease in *** Co-N_(2) catalyst exhibited the highest NH_(3) synthesis rate of 85.3 mmol gCo^(−1) h^(−1) at 300℃ and 1 MPa,which outperformed most of the previously reported Co-based *** characterizations and theoretical calculations demonstrated that atomically dispersed Co catalyst with low CN could generate more unoccupied Co 3d charges and tetrahedral cobalt(Ⅱ)*** unoccupied Co 3d charge,in turn,promoted the electron donation from the Co active center to the antibonding π-orbital(π*)of N_(2) and expedites N_(2) ***,the Co-N_(2) catalyst with more tetrahedral cobalt(II)sites could effectively facilitate the desorption of N-containing intermediate species(such as*NH_(3) and*N_(2)H_(4))to obtain a high NH_(3) synthesis rate.

关键词： ammonia synthesis coordination number electron transfer geometric structure intermediate species

In Vivo Efficacy of Neuropeptide S on the Expression of Cytokines Indeced by Influenza A Virurs in Ducks

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Animal Husbandry and Feed Science 2019年第3期11卷 92-97页

作者： Ma Yijie Jiang Zongpei zhang tianhua Huang Cuiqin Yang Guihong Key Laboratory of Fujian-Taiwan Animal Pathogen Biology College of Animal Science(College of Bee Science)Fujian Agricultural and Forestry UniversityFujian 350002China College of Animal Science(College of Bee Science) Fujian Agricultural and Forestry UniversityFujian 350002China College of Life Science Longyan UniversityLongyan 364012China

Neuropeptide S(NPS)is involved in severe pathological *** evidence showed NPS regulates the secretion of proinflammatory cytokines in *** study investigated the effect of NPS on the secretion of inflammatory cytokines in ducks with H9N2 infection via intramuscular injection with NPS or NPS receptor(NPSR)*** ducks received 15 nM NPS or 10 nM NPSR antagonist in *** were collected to analyze the expression levels of IL-1β,IL-6,TNF-α,IFN-α,NPS,and the H9N2 gene NP by RT-PCR and real time RT-PCR;samples were fixed to observe the histopathological changes by hematoxylin-eosin *** blood samples were collected(every 30 min,starting 1 h before injections and lasting until 2 h after injections)to measure the serum levels of IL-1β,IL-6,TNF-α,and IFN-αby *** RT-PCR confirmed that the expression of NPS mRNA was increased in H9N2 infection *** data showed NPS treatment could reverse the pathological changes in the duck bursa induced by H9N2 *** the results of real time quantitative RT-PCR and ELISA methods showed NPS and NPSR antagonist treatments could significantly regulate the expression of IFN-α,but not of IL-1β,IL-6 and TNF-α;meanwhile,the levels of increased IFN-α and decreased NP were further prompted by NPS,and NPSR antagonist ***,NPS is involved in the innate immunity response to H9N2 infection via the IFN-αpathway in ducks in *** results indicate NPS affects the immune homeostasis and provides an alternative for anti-H9N2 drugs.

关键词： Neuropeptide S Duck H9N2 Cytokine

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论高校创业教育的系统构建

国家教育行政学院学报 2014年第5期 25-30页

作者：张天华渤海大学辽宁锦州121000

高校创业教育系统构建遵循整体规划、实践导向、能力本位的指导原则,通过建立高校创业教育系统内部的五个体系,即目标体系、课程体系、师资体系、组织体系和评价体系,不断丰富和完善创业教育体系的内涵和结构,推动高校创业教育系统有序... 详细信息

高校创业教育系统构建遵循整体规划、实践导向、能力本位的指导原则,通过建立高校创业教育系统内部的五个体系,即目标体系、课程体系、师资体系、组织体系和评价体系,不断丰富和完善创业教育体系的内涵和结构,推动高校创业教育系统有序运转。

关键词：高校创业教育

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从高原环境特征论西藏环境保护重点

环境保护 2000年第1期28卷 27-29页

作者：张天华西藏自治区环保局拉萨850002

西藏86.1%的土地位于海拔4000m以上的地区 ,受“高”、“寒”等恶劣自然条件的作用 ,生态环境呈自然退化趋势。加上粗放型的经济发展模式 ,也在局部加剧了生态环境的退化。本文对上述环境特征进行分析后 ,提出生物多样性保护、草地生态... 详细信息

西藏86.1%的土地位于海拔4000m以上的地区 ,受“高”、“寒”等恶劣自然条件的作用 ,生态环境呈自然退化趋势。加上粗放型的经济发展模式 ,也在局部加剧了生态环境的退化。本文对上述环境特征进行分析后 ,提出生物多样性保护、草地生态环境建设、4大江源头和上游生态环境保护、藏中“一江两河”(雅鲁藏布江中游、拉萨河、年楚河)流域环境综合整治、环境背景值监测与研究。

关键词：西藏环境保护高原环境环境地学生态系统