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普通延迟焦化装置生产动力类负极焦研究

石油炼制与化工 2025年第1期56卷 117-122页

作者：王慧党建军花飞中海油惠州石化有限公司广东惠州516086

随着锂离子电池负极材料行业的高速增长,其对石油焦原料的需求量越来越大,传统炼油厂如果能利用现有延迟焦化装置生产满足负极材料要求的焦原料,将是提质增效的有效途径。动力类电池要求负极材料能够实现高克容量、高倍率等性能,相应地... 详细信息

随着锂离子电池负极材料行业的高速增长,其对石油焦原料的需求量越来越大,传统炼油厂如果能利用现有延迟焦化装置生产满足负极材料要求的焦原料,将是提质增效的有效途径。动力类电池要求负极材料能够实现高克容量、高倍率等性能,相应地要求负极材料焦原料有高比例的纤维结构和区域结构,这与焦化过程中碳质中间相的形成与生长密切相关。普通延迟焦化装置生产动力类负极焦需从原料和工艺条件两方面寻找改善途径,如掺炼催化裂化油浆,采用低反应温度、高焦化压力、大循环比、长生焦时间操作,并应对上下游衔接、加工效益评估、全厂物料平衡和维持石油焦品质稳定等方面的挑战。

关键词：负极材料石油焦碳质中间相焦化

ON THE CONVERGENCE OF IMPLICIT DIFFERENCE SCHEMES FOR HYPERBOLIC CONSERVATION LAWS

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Journal of Computational Mathematics 2002年第2期20卷 121-128页

作者： hua-zhong Tang hua-mo Wu School of Mathematical Sciences Peking UniversityBeijing 100871China LSEC ICMSECAcademy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100080China

Discusses the treatment of implicit difference approximations to hyperbolic conservation laws with non-convex flux. Information on weighted implicit difference schemes; Convergence of difference scheme; Establishment ... 详细信息

关键词： conservation laws weighted implicit schemes entropy solution

适变与应变:“十五五”时期人口发展规划的新格局、新挑战及其实践路径

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河北学刊 2025年第1期45卷 130-139页

作者：陆杰华冯雨欣北京大学中国社会与发展研究中心北京大学社会学系

“十五五”时期是中国基本实现社会主义现代化承上启下的关键时期,同时也是人口发展深度转型的重要节点。“十五五”人口发展规划的制定必须准确识别人口规模、结构、素质、分布等要素呈现的趋势性变化,及时把握当前人口发展的潜在机遇... 详细信息

“十五五”时期是中国基本实现社会主义现代化承上启下的关键时期,同时也是人口发展深度转型的重要节点。“十五五”人口发展规划的制定必须准确识别人口规模、结构、素质、分布等要素呈现的趋势性变化,及时把握当前人口发展的潜在机遇和堵点难点,根据人口发展新格局适时调整应变思路,不断推进人口自身均衡发展,以及人口与经济社会、资源环境的协调发展。从长远来看,人口发展规划的制定还需要纵向锚定人口高质量发展的战略目标,形成应对未来人口发展新变化的超前预案。

关键词： “十五五” 人口发展规划人口高质量发展适变与应变

ON THE CELL ENTROPY INEQUALITY FOR THE FULLY DISCRETE RELAXING SCHEMES

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Journal of Computational Mathematics 2001年第5期19卷 511-518页

作者： hua-zhong Tang hua-mo Wu School of Mathematical Sciences Peking UniversityBeijing 100871China LSEC JCMSECAcademy of Mathematics and Systems SciencesChinese Academy of SciencesBeijing 100080China

Presents a study on the cell entropy inequality for two classes of fully discrete relaxing schemes approximating scalar conservation laws. Main advantage of the schemes; Review of the construction of the relaxing syst... 详细信息

关键词： the relaxing schemes entropy inequality conservation laws

Using a zeolite medium biofilter to remove organic pollutant and ammonia simultaneously

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Journal of Environmental Sciences 2004年第1期16卷 90-93页

作者： TIANWen-hua WENXiang-hua QIANYi ESPCStateKeyJointLaboratory DepartmentofEnvironmentScienceandEngineeringTsinghuaUniversityBeijing100084China

A pilot scale zeolite medium biological aerated filter(ZBAF) was designed and used to treat municipal wastewater. It showed that ZBAF could simultaneously remove chemical oxygen demand(COD), ammonia-N and turbidity to satisfied degree at a hydraulic retention time(HRT) of 0.95 h. Their average removal efficiencies were 73.9%, 88.4% and 96.2% with the corresponding average effluent concentrations of 43.4 mg/L, 3.5 mg/L and 3.7 NTU, respectively. These effluent items met with the water quality standard of the treated water reused for cooling water. The COD removal volumetric loading rate increased proportionally with its applied volumetric loading rate with its maximum of 7.1 kg/(m 3·d). Ammonia-N removal loading rate also increased proportionally with its applied loading rate at HRT of longer than 0.95 h and the feasible maximum removal loading rate was 0.9 kg/(m 3·d). The COD loading rate did not affect the ammonia-N removal efficiency significantly when it was lower than 5.5 kg/(m 3·d). ZBAF has good application prospect for its low cost and high removal efficiency in the future.

关键词： ammonia-N removal biological aerated filter hydraulic retention time natural zeolite volumetric loading rate

激光诱导荧光技术与地下水重金属原位检测应用进展

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岩矿测试 2025年第1期44卷 19-34页

作者：毛康薛家奇陈卓张华中国科学院地球化学研究所环境地球化学国家重点实验室贵州贵阳550081

对地下水重金属污染进行现场检测,是快速识别重金属种类和评价污染程度的重要手段。激光诱导荧光技术(LIF)利用特定荧光探针,在目标重金属存在下,通过激光诱导荧光探针产生/猝灭荧光,从而完成对重金属的识别和检测,具有快速甄别地下水... 详细信息

对地下水重金属污染进行现场检测,是快速识别重金属种类和评价污染程度的重要手段。激光诱导荧光技术(LIF)利用特定荧光探针,在目标重金属存在下,通过激光诱导荧光探针产生/猝灭荧光,从而完成对重金属的识别和检测,具有快速甄别地下水重金属污染特性和无损获取其价态的优势。本文在简述LIF检测重金属原理和LIF原位检测地下水重金属装备基础上,重点从荧光探针合成及其在重金属传感检测方法的构建上总结了基于不同荧光探针的LIF现场检测重金属的研究进展。目前可用于重金属检测的荧光探针包括以小分子探针、有机大分子和聚集诱导发光为主的有机荧光探针和以金纳米簇、量子点和金属有机框架材料为代表的纳米荧光探针。这些探针的合成及其对应的传感检测方法的构建表明LIF技术在地下水重金属检测中具有巨大优势。而针对地下水重金属检测的LIF设备研发方面的成果虽不如荧光传感检测方法丰富,但已研制出部分重金属的传感器和检测装备,表现出良好的应用前景。未来研究将会聚焦在地下水重金属主控因子识别和抗干扰技术研发、荧光探针合成与LIF检测方法构建、重金属传感部件和检测装备集成研制,以及检测技术标准化,为后续场地地下水典型重金属LIF检测技术的研究提供参考。

关键词：地下水重金属激光诱导荧光荧光探针现场检测

KINETIC FLUX VECTOR SPLITTING FOR THE EULER EQUATIONS WITH GENERAL PRESSURE LAWS

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Journal of Computational Mathematics 2004年第4期22卷 622-632页

作者： hua-zhongTang LMAM SchoolofMathematicalSciencesPekingUniversityBeijing100871China

This paper attempts to develop kinetic flux vector splitting (KFVS) for the Euler equations with general pressure laws. It is well known that the gas distribution function for the local equilibrium state plays an important role in the construction of the gas-kinetic schemes. To recover the Euler equations with a general equation of state (EOS), a new local equilibrium distribution is introduced with two parameters of temperature approximation decided uniquely by macroscopic variables. Utilizing the well-known connection that the Euler equations of motion are the moments of the Boltzmann equation whenever the velocity distribution function is a local equilibrium state, a class of high resolution MUSCL-type KFVS schemes are presented to approximate the Euler equations of gas dynamics with a general EOS. The schemes are finally applied to several test problems for a general EOS. In comparison with the exact solutions, our schemes give correct location and more accurate resolution of discontinuities. The extension of our idea to multidimensional case is natural.

关键词： General equation of state KFVS method The Euler equations

THE MAXIMUM PRINCIPLE FOR PARTIALLY OBSERVED OPTIMAL CONTROL OF FORWARD-BACKWARD STOCHASTIC SYSTEMS WITH RANDOM JUMPS

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Journal of Systems Science & Complexity 2011年第6期24卷 1083-1099页

作者： hua XIAO School of Mathematics and Statistics Shandong University at Weihai Weihai 264209 China School of Mathematics Shandong University Jinan 250100 China

This paper studies the problem of partially observed optimal control for forward-backward stochastic systems which are driven both by Brownian motions and an independent Poisson random measure. Combining forward-backward stochastic differential equation theory with certain classical convex variational techniques, the necessary maximum principle is proved for the partially observed optimal control, where the control domain is a nonempty convex set. Under certain convexity assumptions, the author also gives the sufficient conditions of an optimal control for the aforementioned optimal optimal problem. To illustrate the theoretical result, the author also works out an example of partial information linear-quadratic optimal control, and finds an explicit expression of the corresponding optimal control by applying the necessary and sufficient maximum principle.

关键词： Forward-backward stochastic differential equations maximum principle partially observed optimal control random jumps.

Contact theory and algorithm

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Science China(Technological Sciences) 2021年第8期64卷 1775-1790页

作者： SHI Gen-hua University of Chinese Academy of Sciences Beijing100049China DDA-NMM Company Beijing100026China School of Qilu Transportation Shandong UniversityJinan250100China

In discontinuous computations,contacts between two general blocks A and B are common and represent a fundamental *** paper presents a mathematically proven theory and algorithm to address this *** the proposed approach,a reference point a0 is selected from block A,and the contacts between blocks A and B are transferred to the contact of the reference point a0 and the entrance block E(A,B).Discontinuity related computations DEM,DDA,and FEM can use this mathematically proven theory and algorithm directly.

关键词： contact discontinuity entrance block computational geometry