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松软煤层放顶煤开采瓦斯治理和防灭火技术研究

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能源与节能 2024年第7期 190-193页

作者：吉青青霍州煤电集团吕临能化有限公司庞庞塔煤矿山西吕梁033000

松软煤层放顶煤开采面临着瓦斯治理和防灭火技术难题。结合了9-806工作面的具体情况,对开采过程中面临的瓦斯治理和防灭火问题进行了系统的分析,并采取了针对性的防治措施。结果显示,瓦斯防治受到了通风设施损坏、瓦斯含量大和采动的影... 详细信息

松软煤层放顶煤开采面临着瓦斯治理和防灭火技术难题。结合了9-806工作面的具体情况,对开采过程中面临的瓦斯治理和防灭火问题进行了系统的分析,并采取了针对性的防治措施。结果显示,瓦斯防治受到了通风设施损坏、瓦斯含量大和采动的影响,防灭火受到了易燃气体、浮煤以及防灭火技术的影响。为此,需要从产学研合作制定合理的防灭火措施、投用高负压瓦斯抽放泵、减少巷道漏风、做好有毒有害气体的监测工作等几个方面出发进行防治。

关键词：煤矿安全松软煤层防灭火瓦斯防治

文理综合学报面向主办高校的出版服务能力研究

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宁波工程学院学报 2024年第2期36卷 57-64页

作者：王继国季庆庆江苏理工学院学报编辑部江苏常州213001

为了评价文理综合学报面向主办高校的出版服务能力,基于载文量这一最基础、最核心的期刊出版指标,提出理想服务能力、可能服务能力、实际服务能力、服务诚意指数4个概念,并构建了相应的计算模型。以江浙沪12种文理综合学报为样本,进行... 详细信息

为了评价文理综合学报面向主办高校的出版服务能力,基于载文量这一最基础、最核心的期刊出版指标,提出理想服务能力、可能服务能力、实际服务能力、服务诚意指数4个概念,并构建了相应的计算模型。以江浙沪12种文理综合学报为样本,进行了具体研究。结果显示:12种学报的年均载文量较低,且呈逐年下降趋势;主要受载文量偏低影响,其可能服务能力为38.64%;在中低水平的服务诚意指数的进一步影响下,其实际服务能力仅为20.64%;个刊之间差异明显,实际服务能力评价方面《丽水学院学报》得分最高,是《淮阴工学院学报》的4.48倍。建议主办高校从编辑队伍建设、出版经费支持、科研评价适当向学报倾斜等几方面综合施策,切实提高学报的出版服务能力。

关键词：文理综合学报出版服务能力地方本科院校

Synthetic two-dimensional electronics for transistor scaling

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Frontiers of physics 2023年第6期18卷 145-161页

作者： Zihan Wang Yan Yang Bin Hua qingqing ji School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

Two-dimensional(2D)materials have been considered to hold promise for transistor ultrascaling,thanks to their atomically thin body immune to short-channel *** lower channel size limit of 2D transistors is yet to be revealed,as this size is below the spatial resolution of most lithographic *** recent years,chemical approaches such as chemical vapor deposition(CVD)and metalorganic CVD(MOCVD)have been established to grow atomically precise nanostructures and heterostructures,thus allowing for synthetic construction of ultrascaled *** this review,we summarize recent developments on the precise synthesis and defect engineering of electronic nanostructures/heterostructures aiming for transistor *** demonstrate with rich examples that ultrascaled 2D transistors are achievable by finely tuning the“growth-as-fabrication”process and could host a plethora of new device ***,by plotting the scaling trend of 2D transistors,we conclude that synthetic electronics possess superior scaling capability and could facilitate the development of post-Moore nanoelectronics.

关键词： 2D materials nanostructures synthetic electronics transistor scaling

Degradation of p-nitrophenol(PNP) in aqueous solution by mFe/Cu-air-PS system

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Chinese Chemical Letters 2019年第5期30卷 1129-1132页

作者： Heng Zhang qingqing ji Leiduo Lai Gang Yao Bo Lai State Key Laboratory of Hydraulics and Mountain River Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Sino-German Centre for Water and Health Research Sichuan UniversityChengdu 610065China Institute of Environmental Engineering RWTH Aachen UniversityAachenGermany

In this study,batch experiments were conducted to investigate the performance of microscale Fe/Cu bimetallic particles-air-persulfate system(mFe/Cu-air-PS)for p-nitrophenol(PNP)treatment in aqueous ***,the optimal operating parameters(i.e.,aeration rate of 1.0 L/min,theoretical Cu mass loading(TMLCu)of 0.110 g Cu/g Fe,mFe/Cu dosage of 15 g/L,PS total dosage of 15 mmol/L,feeding times of PS of 5,initial pH 5.4)were obtained successively by single-factor *** the optimal conditions,high COD and TOC removal efficiencies(71.0%,65.8%)were obtained after 60 min ***,compared with control experiments(i.e.,mFe/Cu,air,PS,mFe/Cu-air,mFe/Cu–PS,air-PS and mFe-air-PS),mFe/Cu-air-PS system exerted superior performance for pollutants removal due to the synergistic effect between mFe/Cu,air and *** addition,the results of control experiments and radical quenching experiments indicate this reinforcement by feeding of PS was greater than by aeration in m Fe/Cu-air-PS ***,the degradation intermediates of PNP in mFe/Cu-air-PS process were identified and measured by *** on the detected intermediates,the degradation pathways of PNP were proposed comprehensively,which revealed that toxic and refractory PNP in aqueous solution could be decomposed effectively and transformed into lower toxicity *** a result,m Fe/Cu-air-PS system with the performance of oxidation combined reduction can be also a potential technology for the treatment of toxic and refractory PNP contained wastewater.

关键词： p-Nitrophenol(PNP) Microscale Fe/Cu bimetallic particles(mFe/Cu) Persulfate(PS) Air aeration mFe/Cu-air-PS system

Evaluation of Intensive Urban Land Use Based on an Artificial Neural Network Model:A Case Study of Nanjing City,China

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Chinese Geographical Science 2017年第5期27卷 735-746页

作者： QIAO Weifeng GAO Junbo LIU Yansui QIN Yueheng LU Cheng ji qingqing Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China School of Geography Science Nanjing Normal UniversityNanjing 210023China jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China School of Geography Science Xinyang Normal UniversityXinyang 464000Henan ProvinceChina

In this paper, the artificial neural network(ANN) model was used to evaluate the degree of intensive urban land use in Nanjing City, China. The construction and application of the ANN model took into account the comprehensive, spatial and complex nature of urban land use. Through a preliminary calculation of the degree of intensive land use of the sample area, representative sample area selection and using the back propagation neural network model to train, the intensive land use level of each evaluation unit is finally determined in the study area. Results show that the method can effectively correct the errors caused by the limitations of the model itself and the determination of the ideal value and weights when the multifactor comprehensive evaluation is used alone. The ANN model can make the evaluation results more objective and practical. The evaluation results show a tendency of decreasing land use intensity from the core urban area to the periphery and the industrial functional area has relatively low land use intensity compared with other functional areas. Based on the evaluation results, some suggestions are put forward, such as transforming the mode of urban spatial expansion, strengthening the integration and potential exploitation of the land in the urban built-up area, and strengthening the control of the construction intensity of protected areas.

关键词： urban land intensive use functional area artificial neural network (ANN) model Nanjing City

Uniform single-layer graphene growth on recyclable tungsten foils

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Nano Research 2015年第2期8卷 592-599页

作者： Zhiyu Zou Xiuju Song Ke Chen qingqing ji Yanfeng Zhang Zhongfan Liu Center for Nanochemistry Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry for Unstable and Stable Species College of Chemistry and Molecular Engineering Academy for Advanced Interdisciplinary Studies Peking University Beijing 100871 China Key Laboratory for Special Functional Materials of Ministry of Education Henan University Kaifeng 475004 China ing 100871 China

To meet the rising demand of graphene in electronics and optoelectronics, developing an efficient synthesis strategy for effective control of the layer thickness is highly necessary. Herein, we report the synthesis of strictly single- layer graphene on the foil of an early transition metal, tungsten （W）, via a simple chemical vapor deposition route. The cracking of hydrocarbons is facilitated by the catalytically active metal surface of W, while the subsequent two-dimensional growth is mediated by the carbide-forming ability within the underlying bulk, leading to the formation of uniform monolayer graphene. The as-grown graphene layers can be transferred onto target substrates rapidly through the recently developed electrochemical method, which also allows for reuse of the substrates at least five times without introducing quality deteriora- tion. Moreover, considering the refractory nature of W foils, a complementary component of nickel is added, by means of which the growth temperature of graphene can be significantly reduced. In brief, a highly-efficient and low-cost synthesis route has been developed for the growth of graphene towards large-area uniformity, single-layer thickness and high crystalline quality.

关键词： graphene chemical vapor deposition single layer tungsten carbide recyclable substrate

Clean transfer of graphene on Pt foils mediated by a carbon monoxide intercalation process

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Nano Research 2013年第9期6卷 671-678页

作者： Donglin Ma Yanfeng Zhang Mengxi Liu qingqing ji Teng Gao Yu Zhang Zhongfan Liu Center for Nanochemistry (CNC) Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Academy for Advanced Interdisciplinary Studies Peking University Beijing 100871 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China

Noble metals such as Pt are a perfect substrate for the catalytic growth of monolayer graphene. However, the requirements of the subsequent transfer process are not compatible with the traditional etching method. In this work, we find that the interaction of graphene with Pt foil can be weakened through the intercalation of carbon monoxide （CO） under ambient pressure. This intercalation process occurs on both hexagonal-shape graphene islands and irregular graphene patches on changing the CO partial pressure from 0 to 0.6 MPa, as observed by scanning electron microscopy （SEM）, Raman spectroscopy and X-ray photoemission spectroscopy. We demonstrate that, on a practical timescale, the intercalation ratio is proportional to the partial pressure of CO. Furthermore, we develop a clean transfer method of CO-intercalated graphene with water as a peeling agent. We show that this method enables the transfer of tens of micrometer-scale graphene patches onto SiO2/Si, which are free from metal or oxide particle contamination. This transfer method should be a significant step towards the dean transfer of graphene, as well as the recydable use of noble metal substrates.

关键词： graphene transfer clean etching free CO intercalation Pt foils

Bioinspired synthesis of CVD graphene flakes and graphene-supported molybdenum sulfide catalysts for hydrogen evolution reaction

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Nano Research 2016年第1期9卷 249-259页

作者： Ke Chen Cong Li Zhaolong Chen Liurong Shi Sathish Reddy Huan Meng qingqing ji Yanfeng Zhang Zhongfan Liu Center for Nanochemistry (CNC) Beijing Science and Engineering Center for Low Dimensional Carbon Materials Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Key Laboratory for Special Functional Materials of Ministry of Education Henan University Kaifeng 475004 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China

Chemical vapor deposition has been the most-promising approach for growing large-area high-quality graphene films on planar substrates. Beyond the lateral growth, the synthesis of three-dimensional （3D） graphene has also been demon- strated recently on metal foams and insulating nanoparticles for exploring their applications in electrochemical electrodes. However, the existing approaches need either to prefabricate abundant starting substrates, or to construct porous frameworks for graphene growth. Herein, we report a straightforward, bioinspired strategy for growing large-quantity graphene flakes on cuttlebone substrates using the chemical vapor deposition （CVD） method. The separated graphene flakes from growth substrates are highly crystalline and layer-thickness controllable, outperforming the traditional chemically exfoliated graphene with few surface groups. Due to their inheriting the biomineral-derived morphology, the 3D graphene microstructures show a highly exposed and curved surface, which can load more MoSx（x ≥ 2） catalysts than other planar supports for highly efficient hydrogen generation. Briefly, the bioinspired approach is expected to achieve a reasonable balance between quality and quantity for graphene production, thus propelling its wide applications in energy storage and conversion devices.

关键词： graphene bioinspired synthesis chemical vapor deposition three-dimensional hydrogen evolutionreaction

Transformation of monolayer MoS2 into multiphasic MoTe2： Chalcogen atom-exchange synthesis route

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Nano Research 2017年第8期10卷 2761-2771页

作者： Qiyi Fang Zhepeng Zhang qingqing ji Siya Zhu Yue Gong Yu Zhang jianping Shi Xiebo Zhou Lin Gu Qian Wang Yanfeng Zhang Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China Center for Nanochemistry (CNC) Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Academy for Advanced lnterdisciplinary Studies Peking University Beijing 100871 China Center for Applied Physics and Technology Peking University Beijing 100871 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Collaborative Innovation Center of Quantum Matter Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100190 China

Molybdenum ditelluride （MoTe2）, which is an important transition-metal dichalcogenide, has attracted considerable interest owing to its unique properties, such as its small bandgap and large Seebeck coefficient. However, the batch production of monolayer MoTe2 has been rarely reported. In this study, we demonstrate the synthesis of large-domain （edge length exceeding 30 μm）, monolayer MoTe2 from chemical vapor deposition-grown monolayer MoS2 using a chalcogen atom-exchange synthesis route. An in-depth investigation of the tellurization process reveals that the substitution of S atoms by Te is prevalently initiated at the edges and grain boundaries of the monolayer MoS2, which differs from the homogeneous selenization of MoS2 flakes with the formation of alloyed Mo-S-Se hybrids. Moreover, we detect a large compressive strain （approximately -10%） in the transformed MoTe2 lattice, which possibly drives the phase transition from 2H to 1T＇ at the reaction temperature of 500 ℃. This phase change is substantiated by experimental facts and first-principles calculations. This work introduces a novel route for the templated synthesis of two-dimensional layered materials through atom substitutional chemistry and provides a new pathway for engineering the strain and thus the intriguing physics and chemistry.

关键词： transition-metal dichacogenide MoTe2 atom exchange multiphase phase transformation