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Construction of coal pitch-based HA-K grafted poly condensates and their excellent anti-temperature and viscosity-reducing properties

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Petroleum Science 2024年第4期21卷 2806-2816页

作者： Jing Tan Wei Zhang xiu-ling Yan hao Zhou Sher Bahadar Khan Seitkhan Azat Shi-You Yan hao-Jie ma Xin-Tai Su Xinjiang Key Laboratory of Clean Conversion and High Value Utilization of Biomass Resources College of Chemistry and Chemical Engineering Yili Normal University school of Environment and Energy Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling South China University of Technology Drilling Fluid Branch of CNPC Xibu Drilling Engineering Company Limited Department of Chemistry Faculty of Science King Abdulaziz University PO Box 80203 Faculty of Chemistry and Chemical Technology Al-Farabi Kazakh National University Urumchi Huatailong Chemical Additives Co. Ltd.

Humic acids(HAs) are widely used as filtrate and viscosity reducers in drilling fluids. However, their practical utility is limited due to poor stability in salt resistance and high-temperature resistance. Hightemperature coal pitch(CP) is a by-product from coal pyrolysis above 650.C. The substance's molecular structure is characterized by a dense arrangement of aromatic hydrocarbon and alkyl substituents. This unique structure gives it unique chemical properties and excellent drilling performance, surpassing traditional humic acids in drilling operations. Potassium humate is prepared from CP(CP-HA-K) by thermal catalysis. A new type of high-quality humic acid temperature-resistant viscosity-reducer(Graft CP-HA-K polymer) is synthesized with CP-HA-K, hydrolyzed polyacrylonitrile sodium salt(Na-HPAN),urea, formaldehyde, phenol and acrylamide(AAM) as raw materials. The experimental results demonstrate that the most favorable conditions for the catalytic preparation of CP-HA-K are 1 wt% catalyst dosage, 30 wt% KOH dosage, a reaction temperature of 250.C, and a reaction time of 2 h, resulting in a maximum yield of CP-HA-K of 39.58%. The temperature resistance of the Graft CP-HA-K polymer is measured to be 177.39.C, which is 55.39.C higher than that of commercial HA-K. This is due to the abundant presence of amide, hydroxyl, and amine functional groups in the Graft CP-HA-K polymer,which increase the length of the carbon chains, enhance the electrostatic repulsion on the surface of solid particles. After being aged to 120.C for a specified duration, the Graft CP-HA-K polymer demonstrates significantly higher viscosity reduction(42.12%) compared to commercial HA-K(C-HA-K). Furthermore,the Graft CP-HA-K polymer can tolerate a high salt concentration of 8000 mg.L-1, measured after the addition of optimum amount of 3 wt% Graft CP-HA-K polymer. The action mechanism of Graft CP-HA-K polymer on high-temperature drilling fluid is that the Graft CP-HA-K polymer can increase the re

关键词： Viscosity breaker Heat resistance Base mud Graft CP-HA-K polymer CP Salt resistance

Coherence resonance and bi-resonance by time-periodic coupling strength in Hodgkin-Huxley neuron networks

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Science china Chemistry 2012年第2期55卷 256-261页

作者： lin xiu gong yubing WANG Li ma xiaoguang school of physics Ludong University Yantai 264025 China

We study the effect of time-periodic coupling strength on the spiking coherence of Newman-Watts networks of Hodgkin-Huxley(HH) neurons with non-Gaussian *** is found that the spiking can exhibit coherence resonance(CR) when the extent of deviation of non-Gaussian noise from Gaussian noise and the amplitude of the coupling strength are *** particular,coherence bi-resonance(CBR) is observed when the frequency of the coupling strength is varied,and the CBR is always observed when the frequency is equal to,or a multiple of,the spiking period,manifesting as the locking between the frequencies of the spiking and the coupling *** results show that a time-periodic coupling strength may play a more constructive and efficient role in enhancing the spiking coherence of the neuronal networks than a constant coupling *** findings provide insight into the role of time-periodic coupling strength for enhancing the time precision of information processing in neuronal networks.

关键词： neuronal network time-periodic coupling strength coherence resonance and bi-resonance non-Gaussian noise

Concurrent hetero-/homo-geneous electrocatalysts to bi-phasically mediate sulfur species for lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第6期93卷 663-668,I0016页

作者： Rui-Bo lingHu Jin-xiu Chen Jin-hao Zhang Bo-Quan Li Qing-Shan Fu Gulnur Kalimuldina Geng-Zhi Sun Yunhu Han Long Kong Xi’an Institute of Flexible Electronics(IFE) Northwestern Polytechnical UniversityXi’an 710129ShaanxiChina Institute of Advanced materials Nanjing Tech UniversityNanjing 211816JiangsuChina Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Department of Mechanical and Aerospace Engineering School of Engineering and Digital SciencesNazarbayev UniversityKabanbay Batyr Ave.53Astana 010000Kazakhstan

Expediting redox kinetics of sulfur species on conductive scaffolds with limited charge accessible surface is considered as an imperative approach to realize energy-dense and power-intensive lithium-sulfur(Li-S)*** this work,the concept of concurrent hetero-/homo-geneous electrocatalysts is proposed to simultaneously mediate liquid-solid conversion of lithium polysulfides(LiPSs)and solid lithium disulfide/sulfide(Li_(2)S_(2)/Li_(2)S)propagation,the latter of which suffers from sluggish reduction kinetics due to buried conductive scaffold surface by extensive deposition of Li_(2)S_(2)/Li_(2)*** selected model material to verify this concept is a two-in-one catalyst:carbon nanotube(CNT)scaffold supported iron-cobalt(Fe-Co)alloy nanoparticles and partially carbonized selenium(C-Se)*** Fe-Co alloy serves as a heterogeneous electrocatalyst to seed Li_(2)S_(2)/Li_(2)S through sulphifilic active sites,while the C-Se sustainably releases soluble lithium polyselenides and functions as a homogeneous electrocatalyst to propagate Li_(2)S_(2)/Li_(2)S via solution *** bi-phasic mediation of the sulfur species benefits reduction kinetics of LiPS conversion,especially for the massive Li_(2)S_(2)/Li_(2)S growth scenario by affording an additional solution directed route in case of conductive surface being largely *** strategy endows the Li-S batteries with improved cycling stability(836 ma h g^(-1)after 180 cycles),rate capability(547 ma h g^(-1)at 4 C)and high sulfur loading superiority(2.96 ma h cm^(-2)at 2.4 mg cm^(-2)).This work hopes to enlighten the employment of bi-phasic electrocatalysts to dictate liquid-solid transformation of intermediates for conversion chemistry batteries.

关键词： Lithium-sulfur batteries Electrocatalysis Lithium polysulfides Sulfur cathode Energy density

Theoretical characterization of the adsorption configuration of pyrrole on Si(100)surface by x-ray spectroscopy

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Chinese physics B 2024年第2期33卷 430-435页

作者：李好情明静姜志昂李海波马勇宋秀能 school of physics and Electronics Shandong Normal UniversityJinan 250358China

The possible configurations of pyrrole absorbed on a Si(100)surface have been investigated by x-ray photoelectron spectroscopy(XPS)and near-edge x-ray absorption fine structure(NEXAFS)*** C-1s XPS and NEXAFS spectra of these adsorption configurations have been calculated by using the density functional theory(DFT)method and fullcore hole(FCH)approximation to investigate the relationship between the adsorption configurations and the *** result shows that the XPS and NEXAFS spectra are structurally dependent on the configurations of pyrrole absorbed on the Si(100)*** with the XPS,the NEXAFS spectra are relatively sensitive to the adsorption configurations and can accurately identify *** NEXAFS decomposition spectra produced by non-equivalent carbon atoms have also been calculated and show that the spectral features vary with the diverse types of carbon atoms and their structural environments.

关键词： pyrrole silicon surface x-ray photoelectron spectroscopy(XPS) near-edge x-ray absorption fine structure(NEXAFS)

结合局部全局特征与多尺度交互的三维多器官分割网络

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中国图象图形学报 2024年第3期29卷 655-669页

作者：柴静雯李安康张浩马泳梅晓光马佳义武汉大学电子信息学院武汉430072

目的高度适形放射治疗是常用的癌症治疗方法,该方法的有效性依赖于对癌组织和周边多个危及器官(organ at risk,OAR)解剖结构的精确刻画,因此研究三维图像多器官的高精度自动分割具有重要意义。以视觉Transformer(vision Transformer,V... 详细信息

目的高度适形放射治疗是常用的癌症治疗方法,该方法的有效性依赖于对癌组织和周边多个危及器官(organ at risk,OAR)解剖结构的精确刻画,因此研究三维图像多器官的高精度自动分割具有重要意义。以视觉Transformer(vision Transformer,ViT)和卷积神经网络(convolutional neural network,CNN)结合为代表的三维医学图像分割方法表现出了丰富的应用优势。然而,这类方法往往忽略同一尺度内和不同尺度间的信息交互,使得CNN和ViT特征的提取和融合受限。本文提出一种端到端多器官分割网络LoGoFUNet(local-global-features fusion UNet),旨在应对现有方法的缺陷。方法首先,针对单一器官分割,提出在同一尺度下并行提取并融合CNN和ViT特征的LoGoF(local-global-features fusion)编码器,并构建了一个端到端的三维医学图像分割多尺度网络M0。此外,考虑到器官内部以及器官之间的相互关系,该方法在M0网络的基础上设计并引入了多尺度交互(multi-scale interaction,MSI)模块和注意力指导(attention guidance,AG)结构,最终形成了LoGoFUNet。结果在Synapse数据集和SegTHOR(segmentation of thoracic organs at risk)数据集上,本文方法相比于表现第2的模型,DSC(Dice similarity cofficient)指标分别提高了2.94%和4.93%,而HD95(Hausdorff distance_95)指标则分别降低了8.55和2.45,切实提升了多器官分割任务的性能表现。在ACDC(automatic cardiac diagnosis challenge)数据集上,3D分割方法的适用性大多较差,但LoGoFUNet依然得到了比2D先进方法更好的结果,说明其对数据集的适应能力更强。结论该方法的分割模型综合尺度内和尺度间的信息交互,具有更好的分割结果,且在数据集上的泛化性更好。

关键词：多器官分割深度神经网络(DNN) 视觉Transformer(ViT) 局部全局特征多尺度交互(MSI)

基于Adam算法的光学相控阵输出光束校准方法

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物理学报 2024年第9期73卷 136-144页

作者：王子豪龙烨仇轲徐佳木孙艳玲范修宏马琳廖家莉康永强西安电子科技大学光电工程学院西安710071 西安微电子技术研究所西安710000

基于微纳集成的光波导相控阵芯片是近年来激光雷达技术领域的研究热点.随着激光雷达系统空间分辨这一实际应用需求的不断提高,作为激光雷达系统中的光束控制器件,光波导相控阵需要扩大阵列规模以提升输出光束的空间分辨率.同时也为光波... 详细信息

基于微纳集成的光波导相控阵芯片是近年来激光雷达技术领域的研究热点.随着激光雷达系统空间分辨这一实际应用需求的不断提高,作为激光雷达系统中的光束控制器件,光波导相控阵需要扩大阵列规模以提升输出光束的空间分辨率.同时也为光波导相控阵输出光束的优化校准带来了困难,现有算法不仅光束校准质量不高,且校准效率较低.为此,本文将Adam算法应用于光波导相控阵输出光束校准系统中,通过建模仿真比较了Adam算法与现有SPGD算法和GS算法在光束校准层面上的优劣.同时,搭建实验系统实现了高质量的光束校准,根据校准结果,在Adam算法校准下光波导相控阵输出光束的主旁瓣比优于15.98 dB,对16×16光波导相控阵输出光束校准达到收敛所需的迭代次数低于600次.这一算法在光波导相控阵输出光束校准方面的应用,能够提高光波导相控阵的控制精度和效率,拓展光波导相控阵在激光雷达技术、数字全息技术和生物成像技术等方面的应用.

关键词：光波导相控阵光束校准算法 Adam算法

基于ICP-MS研究转炉钢渣微粉吸附镍和铅的动力学机理

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光谱学与光谱分析 2024年第2期44卷 594-600页

作者：徐修平徐维成于先坤陈煜杨刚张浩金属矿山安全与健康国家重点实验室安徽马鞍山243000 冶金减排与资源综合利用教育部重点实验室(安徽工业大学) 安徽马鞍山243002 中钢集团马鞍山矿山研究院股份有限公司安徽马鞍山243000 南京农业大学草业学院江苏南京210095 中冶宝钢技术服务有限公司上海201999 安徽工业大学冶金工程学院安徽马鞍山243032

随着工业化的发展,水体和土壤中的重金属污染日益严重。其中,重金属镍是一种常见的致敏性金属,会引起人体过敏发炎,甚至会引发癌症;血液中铅浓度的超标会危害人的神经系统、心血管系统和生殖系统,造成终身性的危害。因此,治理镍和铅重... 详细信息

随着工业化的发展,水体和土壤中的重金属污染日益严重。其中,重金属镍是一种常见的致敏性金属,会引起人体过敏发炎,甚至会引发癌症;血液中铅浓度的超标会危害人的神经系统、心血管系统和生殖系统,造成终身性的危害。因此,治理镍和铅重金属污染具有十分重要的意义。钢渣是炼钢过程中产生的一种副产物,其存在难以利用与附加值低的问题。同时加之管理制度的不健全,导致大量钢渣露天堆放,对土地资源、地下水源,以及空气质量造成严重影响。钢渣微粉具有比表面积大、多孔、化学活性高等特性,被广泛利用,可以成为吸附材料。本文以转炉钢渣微粉为研究对象,利用激光粒度仪、电感耦合等离子体质谱仪、比表面积与孔隙度吸附仪、X射线荧光光谱仪等测试转炉钢渣微粉的基本性质,重点研究转炉钢渣微粉添加量、重金属初始浓度、溶液pH和吸附时间对转炉钢渣微粉吸附Ni^(2+)、Pb^(2+)的效果,结合吸附动力学与吸附等温线理论揭示转炉钢渣微粉对Ni^(2+)、Pb^(2+)的吸附作用机理,为处理镍、铅重金属污染和工业废水处理提供技术支持与理论依据。结果表明:当转炉钢渣微粉添加量大于12.5 g·L^(-1)、重金属初始浓度小于100 mg·L^(-1)、溶液pH大于3和吸附时间大于120 min时,转炉钢渣微粉对Ni^(2+)、Pb^(2+)的吸附效果良好,即基本达到90%。转炉钢渣微粉对Ni^(2+)、Pb^(2+)的吸附符合准二级动力学模型,吸附速率由边界扩散和颗粒内扩散共同控制,吸附过程以化学吸附为主。转炉钢渣微粉的结构具有多孔性为物理吸附Ni^(2+)、Pb^(2+)提供吸附空间,转炉钢渣微粉的化学成分不仅具有碱性与Ni^(2+)、Pb^(2+)形成络合产物,而且水化过程中CaO与SiO_(2)生成C—S—H凝胶,对Ni^(2+)、Pb^(2+)形成络合吸附与硅酸盐体系包裹。转炉钢渣微粉对Ni^(2+)、Pb^(2+)吸附可能存在多层吸附。吸附Ni^(2+)、Pb^(2+)的过程为优惠吸附,吸附容易进行,其理论最大吸附量分别为18.785和17.002 mg·g^(-1)。

关键词： ICP-MS 转炉钢渣微粉 Ni2+ Pb2+ 吸附动力学

微波辐射制备Bi_(2)O_(3)/NiF光阳极及模拟日光下光电催化氧化降解罗丹明B

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中国环境科学 2024年第1期44卷 150-157页

作者：徐浩高博张留科史焕鑫邢玉鲁赵璇马丙瑞赵宝秀青岛理工大学环境与市政工程学院山东青岛266525 吉林建筑大学材料科学与工程学院吉林长春130119

针对粉体Bi_(2)O_(3)光催化剂光利用效率低及难回收再利用等技术问题,采用浸渍—微波辐射技术在泡沫镍(NiF)上负载Bi_(2)O_(3)来制备Bi_(2)O_(3)/NiF光阳极,并借助SEM,XRD,XPS等手段及电化学工作站分析方法研究了光阳极的形貌结构及光... 详细信息

针对粉体Bi_(2)O_(3)光催化剂光利用效率低及难回收再利用等技术问题,采用浸渍—微波辐射技术在泡沫镍(NiF)上负载Bi_(2)O_(3)来制备Bi_(2)O_(3)/NiF光阳极,并借助SEM,XRD,XPS等手段及电化学工作站分析方法研究了光阳极的形貌结构及光电催化氧化性能.结果显示,花簇状的Bi_(2)O_(3)成功地负载在NiF的三维骨架上,Bi_(2)O_(3)/NiF具有优异的光电转化效率.在最佳制备条件,当光电流密度为15µA/cm^(2),外加电压为2V、RhB初始浓度为8mg/L、pH值为3的条件下,Bi_(2)O_(3)/NiF光电催化氧化降解罗丹明B(RhB)的效率可达95.35%,Bi_(2)O_(3)/NiF光电催化氧化降解RhB符合一级反应动力学方程,自由基淬灭实验证实h+在Bi_(2)O_(3)/NiF光电催化氧化降解RhB过程中起着主要作用.

关键词：罗丹明B 光电催化氧化泡沫镍氧化铋高级氧化

A high-precision hydrodynamic model coupled with the hydrological habitat suitability model to reveal estuarine vegetation distribution

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Journal of Hydrodynamics 2022年第3期34卷 451-466页

作者： Qiao-feng ma Shu-xiu Liang Zhao-chen Sun Wen-hao Hou Xin-yue Hu Rui-jin Zhang State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian116024China school of marine Science and Environment Engineering Dalian Ocean UniversityDalian116023China Operational Oceanographic Institution Dalian Ocean UniversityDalian116023China

In this paper,based on the finite volume method,a high-precision hydrodynamic model coupled with the habitat suitability model is established,and the computational efficiency of the coupled model is improved by a graphics processing unit(GPU)-accelerated *** coupled model is used to solve the problem of the non-conservation of mass that may be caused by the nearshore hydrodynamic model in the processing of wetting and drying,while avoiding the unphysical high velocities at the wetting and drying *** coupled model is applied to simulate the high-precision hydrodynamic process of the Liao River estuary(LRE)and the hydrological habitat suitability of the estuarine vegetation(Suaeda heteroptera)growing in the *** simulated values of the hydrological variables(the water level,the water depth,the current velocity and direction)are highly consistent with the measured *** root mean square errors(RMSE)of the hydrological variables are 0.10m,0.12m/s and 17.24°,***,the simulated combined suitability index(CSI)distribution of Suaeda heteroptera(***)matches with the distribution of *** obtained from the high-resolution remote sensing satellite images during the same time *** ratio of the simulated weighted usable area(WUA)of *** to the area obtained from the remote sensing satellite images during the same period is 81.9%.This study reveals the phenomenon that the distribution of *** in the LRE is highly correlated with the high-precision hydrodynamic processes,and provides a scientific basis and a valuable reference for the conservation and the restoration of the estuarine vegetation.

关键词： High-precision hydrodynamic model habitat suitability model conversation of mass weighted usable area vegetation distribution