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库拜煤田拜城县顺发煤矿A3煤层煤岩煤质特征及其清洁利用方法研究

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石化技术 2024年第2期31卷 104-106页

作者：胡振鹏新疆维吾尔自治区煤田地质局一五六煤田地质勘探队新疆乌鲁木齐830046

顺发煤矿位于新疆拜城县的西北方向,主要含煤地层为侏罗系下统塔里奇克组下段(J_(1)t^(1))A_(1)、A_(2)、A_(3)号煤层。通过收集整理顺发煤矿以往的勘探资料,系统分析了顺发煤矿A3煤层的煤岩物理性质、化学性质、工艺性能及分级分类等... 详细信息

顺发煤矿位于新疆拜城县的西北方向,主要含煤地层为侏罗系下统塔里奇克组下段(J_(1)t^(1))A_(1)、A_(2)、A_(3)号煤层。通过收集整理顺发煤矿以往的勘探资料,系统分析了顺发煤矿A3煤层的煤岩物理性质、化学性质、工艺性能及分级分类等煤质特征,并依据煤质提出清洁利用方法。

关键词：煤岩煤质顺发煤矿 A3煤层清洁利用

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煤岩煤质特征及其清洁利用方式研究

石化技术 2024年第2期31卷 196-198页

作者：胡振鹏新疆维吾尔自治区煤田地质局一五六煤田地质勘探队新疆乌鲁木齐830046

夹皮沟井田神龙煤矿位于新疆维吾尔自治区阜康市辖区的中新生代乌鲁木齐山前拗陷的东段,博格达复背斜弧形推覆体北侧,主要的含煤地层为侏罗系下统八道湾组(J_(1)b)A2、A3、A4煤层。在收集了夹皮沟井田以往勘探资料的基础上,系统分析了... 详细信息

夹皮沟井田神龙煤矿位于新疆维吾尔自治区阜康市辖区的中新生代乌鲁木齐山前拗陷的东段,博格达复背斜弧形推覆体北侧,主要的含煤地层为侏罗系下统八道湾组(J_(1)b)A2、A3、A4煤层。在收集了夹皮沟井田以往勘探资料的基础上,系统分析了神龙煤矿A2煤层的煤岩煤质特征,煤质主要为特低灰、特低硫、低磷、富油、特高热值,可作为配焦用煤和工业动力用煤及良好的民用煤。

关键词：煤岩煤质夹皮沟井田 A2煤层煤炭清洁利用

Determining hubbard U of VO_(2) by the quasi-harmonic approximation

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Chinese Physics B 2024年第1期33卷 623-630页

作者：孔龙娟陆雨航庄新莹周志勇胡振芃 School of Physics Nankai UniversityTianjin 300071China

Vanadium dioxide VO_(2) is a strongly correlated material that undergoes a metal-to-insulator transition around 340 *** order to describe the electron correlation effects in VO_(2), the DFT+U method is commonly employed in ***, the choice of the hubbard U parameter has been a subject of debate and its value has been reported over a wide range. In this paper, taking focus on the phase transition behavior of VO_(2), the hubbard U parameter for vanadium oxide is determined by using the quasi-harmonic approximation(QHA). First-principles calculations demonstrate that the phase transition temperature can be modulated by varying the U values. The phase transition temperature can be well reproduced by the calculations using the Perdew–Burke–Ernzerhof functional combined with the U parameter of 1.5eV. Additionally,the calculated band structure, insulating or metallic properties, and phonon dispersion with this U value are in line with experimental observations. By employing the QHA to determine the hubbard U parameter, this study provides valuable insights into the phase transition behavior of VO_(2). The findings highlight the importance of electron correlation effects in accurately describing the properties of this material. The agreement between the calculated results and experimental observations further validates the chosen U value and supports the use of the DFT+U method in studying VO_(2).

关键词： quasi-harmonic approximation vanadium dioxide first-principles calculation hubbard U

金属镍活性中心在惰性金属载体中的自分散及其催化炔烃选择加氢性能

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Chinese Journal of Catalysis 2024年第6期61卷 259-268页

作者：邓欣郑彩艳李玮杰王佳敏杨迪胡振芃李兰冬南开大学化学学院有机新物质创造前沿科学中心天津300071 南开大学物理科学学院天津300071 物质绿色创造与制造海河实验室天津300192

单位点催化剂因具有较好的活性、较高的原子利用率和目标产物选择性,在基础科学研究及工业生产领域受到了广泛关注.然而,单位点催化剂的合成策略通常较为繁琐,需要精细调控金属活性中心与载体之间的相互作用.较弱的相互作用可能会导致... 详细信息

单位点催化剂因具有较好的活性、较高的原子利用率和目标产物选择性,在基础科学研究及工业生产领域受到了广泛关注.然而,单位点催化剂的合成策略通常较为繁琐,需要精细调控金属活性中心与载体之间的相互作用.较弱的相互作用可能会导致金属活性位点的迁移和聚集,形成金属团簇,进而引发不必要的副反应.另一方面,过分紧密的相互作用可能会限制金属活性位点的原子效率,从而降低反应活性.本文开发了一种简单通用的自分散策略,用于制备金属态单位点催化剂.该方法利用过渡金属活性中心镍在惰性载体(铝和镁)中的自分散行为,成功构筑了含有孤立过渡金属镍活性中心的全金属催化体系.X射线光电子能谱、低能离子散射和球差矫正扫描透射电子显微镜等表征结果证实了镍/铝催化剂中镍物种以金属态存在,且以孤立状态均匀分布于铝基载体的亚表层.在气固相乙炔选择加氢反应中,镍/铝和镍/镁催化剂表现出较好的催化性能,能够实现100%的乙炔转化率和高乙烯选择性.值得注意的是,镍/铝催化剂在碳碳三键选择加氢反应中的催化性能甚至超越了工业界广泛使用的林德拉催化剂.稳定性测试结果表明,镍/铝催化剂在长达90 h的连续反应中,能够维持稳定的乙炔转化率和乙烯选择性,没有明显的活性下降,进一步印证了其在工业应用中的潜在价值.结合动力学分析、原位红外光谱、氢-氘-乙炔脉冲响应实验以及理论计算等结果,详细阐释了镍/铝催化体系上乙炔选择加氢的反应机制.结果表明,氢气分子优先在镍/铝催化剂表面吸附并发生解离,生成氢原子,随后与乙炔分子逐步反应生成乙烯.在该过程中,氢气的解离活化是整个反应过程的决速步.此外,还进一步探讨了镍/铝催化体系对液相炔烃、炔醇选择加氢的性能,发现该催化剂可以在较为温和的条件下高效催化不同官能团修饰的炔烃、炔醇的选择加氢反应,同时保持高底物转化率和较好的烯烃、烯醇选择性,且表现出较好的循环稳定性.综上所述,本文发展了一种全金属单位点催化体系的通用构筑策略,不仅扩展了单位点金属催化体系的合成方法,同时利用全金属体系的本征优势,为化学转化反应过程提供了新的思路.上述发现为设计合成新型高效催化体系提供了重要的理论和实验依据,有望在精细化学品合成工业中得到应用.

关键词：单位点全金属催化剂选择加氢 Ni基催化剂自分散

gt-C3N4 coordinated single atom as an efficient electrocatalyst for nitrogen reduction reaction

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Nano Research 2019年第5期12卷 1181-1186页

作者： Lifu Zhang Wanghui Zhao Wenhua Zhang Jing Chen zhenpeng hu School of Physics Nankai UniversityTianjin 300071China Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy Conversion and Synergetic Innovation Centre of Quantum Information & Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The electrochemical reduction of nitrogen to ammonia is a promising way to produce ammonia at mild *** design and preparation of an efficient catalyst with high ammonia selectivity is critical for the real *** this work,a series of transition metal (TM =Sc,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,Y,Zr,Nb,Mo,Tc,Ru,Rh,Pd,Ag,and Cd) atoms supported by gt-C3N4 (TM/gt-C3N4) are investigated as electrocatalysts for the nitrogen reduction reaction (NRR) based on density functional *** is found that Mo/gt-C3N4 with a limiting potential of-0.82 V is the best catalyst for standing-on adsorbed N2 *** for lying-on adsorbed N2 cases,V/gt-C3N4 with a limiting potential of-0.79 V is berer than other *** is believed that this work provides several promising candidates for the non-noble metal electrocatalysts for NRR at mild condition.

关键词： nitrogen reduction reaction single-atom catalyst first-principles calculation Gibbs free energy

HSH-C_(10):A new quasi-2D carbon allotrope with a honeycomb-star-honeycomb lattice

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Chinese Chemical Letters 2022年第8期33卷 3941-3946页

作者： Qian Gao Lifu Zhang Caiyan Zheng Shulai Lei Shujuan Li zhenpeng hu School of Physics Nankai UniversityTianjin 300071China hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyang 441053China Institute of Mathematics Free University of BerlinArnimallee 6Berlin D-14195Germany

Two-dimensional(2 D)materials with honeycomb,kagome or star lattice have been intensively studied because electrons in such lattices could give rise to exotic quantum *** order to improve structural diversity of 2 D materials to achieve unique properties,here we propose a new quasi-2 D honeycombstar-honeycomb(HSH)lattice based on first-principles calculations.A carbon allotrope named HSH-C_(10) is designed with the HSH lattice,and its mechanical properties have been intensively investigated through total energy,phonon dispersion,ab initio molecular dynamic simulations,as well as elastic constants *** the classical covalent bonds,there is an interesting charge-shift bond in this material from the chemical bonding ***,through the analysis of electronic structure,HSH-C_(10) is predicted to be a semiconductor with a direct band gap of 2.89 e V,which could combine the desirable characteristics of honeycomb and star ***,by modulating coupling strength,a flat band near the Fermi level can be obtained in compounds HSH-C_(6)Si_(4) and HSH-C_(6)Ge_(4),which have potential applications in *** into such mixed lattice would inspire new materials with properties we have yet to imagine.

关键词： Carbon allotrope Two-dimensional lattice Charge-shift bond Flat band First-principles

A New Class of Infeasible InteriorPoint Algorithm for Linear Complementarity Problem

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Wuhan University Journal of Natural Sciences 2013年第3期18卷 247-253页

作者： GONG Xiaoyu hu zhenpeng WANG Xianjia School of Water Resources and Hydropower Wuhan University

This paper proposes an infeasible interior-point algorithm for linear complementarity problem with full-Newton *** main iteration consists of a feasibility step and several centrality *** more than O（n log（n /ε））iterations are required for getting ε-solution of the problem at hand,which coincides with the best-known bound for infeasible interior-point algorithms.

关键词： linear complementarity problem infeasible interiorpoint method full-Newton step polynomial complexity

Metallic mesocrystal nanosheets of vanadium nitride for high-performance all-solid-state pseudocapacitors

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Nano Research 2015年第1期8卷 193-200页

作者： Wentuan Bi zhenpeng hu Xiaogang Li Changzheng Wu Junchi Wu Yi Xie Hefei National Laboratory for Physical Sciences at Microscale and Collaborative Innovation Center of Chemistry for Energy Materials University of Science and Technology of China Hefei 230026 China School of Physics Nankai University Tianjin 300071 China

Transition metal nitrides （TMNs） are of particular interest by virtue of their synergic advantages of superior electrical conductivity, excellent environmental durability and high reaction selectivity, yet it is difficult to achieve flexible design and operation. Herein, mesocrystal nanosheets （MCNSs） of vanadium nitride （VN） are synthesized via a confined-growth route from thermally stable layered vanadium bronze, representing the first two-dimensional （2D） metallic mesocrystal in inorganic compounds. Benefiting from their single-crystalline-like long-range electronic connectivity, VN MCNSs deliver an electrical conductivity of 1.44×10^5 S/m at room temperature, among the highest values observed for 2D nanosheets. Coupled with their unique pseudocapacitance, VN MCNS-based flexible supercapacitors afford a superior volumetric capacitance of 1,937 mF/cm3. Nitride MCNSs should have wide applications in the energy storage and conversion fields because their intrinsic high conductivity is coupled with the reactivity of inorganic lattices.

关键词： vanadium nitride mesocrystal nanosheets confined growth supercapacitors chemical and thermal stability

pH-Sensitive assembly/disassembly gold nanoparticles with the potential of tumor diagnosis and treatment

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Science China Chemistry 2019年第1期62卷 105-117页

作者： Jinlong Ma Xiaomin Li zhenpeng hu Xinyu Wang Yapei Zhang Wei Wang Qiang Wu Zhi Yuan Key Laboratory of Functional Polymer Materials of Ministry of Education Institute of Polymer Chemistry College of Chemistry Nankai University Collaborative Innovation Center of Chemical Science and Engineering Nankai University

Due to the ability to combine the separately unique characteristics of assembled and disassembled nanoparticles(NPs), the stimuli-responsive self-assembly of NPs has attracted considerable interest in functional material applications especially biomaterials. Here we demonstrate a facile and versatile approach to regulate the self-assembly process and transition pH of Au NPs by fine-tuning the co-modified pH-responsive compounds and poly(ethylene glycol)(PEG). Importantly the transition pH(ΔpH=0.4) of the system can be predetermined in the range of 8.2–5.8(assembled to disassembled) and 8.2–4.2(disassembled to assembled), which ideally covers the pH of normal tissue, tumor tissue milieu and organelles. The results of fluorescence imaging, Raman spectroscopy and photothermal conversion of the stimuli-responsive Au NPs shows the potential application for tumor specificity theranostics. In a nutshell this study provides a useful toolkit to design tumor-activatable self-assembled NPs with high specificity and universality.

关键词： pH-sensitive assemble disassemble gold nanoparticles transition pH