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Probing the interaction between asphaltene-wax and its effects on the crystallization behavior of waxes in heavy oil via molecular dynamics simulation

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Petroleum Science 2024年第4期21卷 2839-2848页

作者： Yong Hu Xi Lu Hai-Bo Wang Ji-chao fang Yi-Ning Wu Jian fang Sun SINOPEC Petroleum Exploration and Production Research Institute Shandong Key Laboratory of Oilfield Chemistry School of Petroleum Engineering China University of Petroleum (East China)

High content of asphaltenes and waxes leads to the high pour point and the poor flowability of heavy oil,which is adverse to its efficient development and its transportation in *** the interaction mechanism between asphaltene-wax is crucial to solve these problems,but it is still *** this paper,molecular dynamics simulation was used to investigate the interaction between asphaltenewax and its effects on the crystallization behavior of waxes in heavy *** show that molecules in pure wax are arranged in a paralleled *** wax molecules in heavy oil,which are close to the surface of asphaltene aggregates,are bent and arranged *** the mass fraction of asphaltenes in asphaltene-wax system(ωasp) is 0-25 wt%,the attraction among wax molecules decreases and the bend degree of wax molecules increases with the increase of ω*** ωaspincreases from 0 to 25 wt%,and the attraction between asphaltene-wax is stronger than that among *** causes that the wax precipitation point changes from 353 to 333 *** the ωaspincreases to 50 wt%,wax molecules are more dispersed owing to the steric hindrance of asphaltene aggregates,and the interaction among wax molecules transforms from attraction to *** causes that the ordered crystal structure of waxes can't be formed at normal ***,the asphaltene,with the higher molecular weight or the more hetero atoms,has more obvious inhibition to the formation of wax ***,resins also have an obvious inhibition on the wax crystal due to the formation of asphalteneresin aggregates with a larger *** results reveal the interaction mechanism between asphaltene-wax,and provide useful guidelines for the development of heavy oil.

关键词： Heavy oil Interaction mechanism Asphaltenes Waxes Molecular dynamics

A highly sensitive LITES sensor based on a multi-pass cell with dense spot pattern and a novel quartz tuning fork with low frequency

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Opto-Electronic Advances 2024年第3期7卷 26-34页

作者： Yahui Liu Shunda Qiao chao fang Ying He Haiyue Sun Jian Liu Yufei Ma National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of TechnologyHarbin 150000China Zhengzhou Research Institute Harbin Institute of TechnologyZhengzhou 450000China Advanced Microscopy and Instrumentation Research Center School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China.

A highly sensitive light-induced thermoelectric spectroscopy(LITES)sensor based on a multi-pass cell(MPC)with dense spot pattern and a novel quartz tuning fork(QTF)with low resonance frequency is reported in this *** erbi-um-doped fiber amplifier(EDFA)was employed to amplify the output optical power so that the signal level was further *** optical path length(OPL)and the ratio of optical path length to volume(RLV)of the MPC is 37.7 m and 13.8 cm^(-2),respectively.A commercial QTF and a self-designed trapezoidal-tip QTF with low frequency of 9461.83 Hz were used as the detectors of the sensor,*** target gas selected to test the performance of the system was acetylene(C2H2).When the optical power was constant at 1000 mW,the minimum detection limit(MDL)of the C2H2-LITES sensor can be achieved 48.3 ppb when using the commercial QTF and 24.6 ppb when using the trapezoid-al-tip *** improvement of the detection performance by a factor of 1.96 was achieved after replacing the commer-cial QTF with the trapezoidal-tip QTF.

关键词： light-induced thermoelectric spectroscopy quartz tuning fork multi-pass cell gas sensing

Strong electron correlation-induced Mott-insulating electrides of Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)

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Matter and Radiation at Extremes 2024年第3期9卷 74-82页

作者： Ya Xu Lu Zheng Yunkun Zhang Zhuangfei Zhang QianQian Wang Yuewen Zhang Liangchao Chen chao fang Biao Wan Huiyang Gou Key Laboratory of Material Physics of Ministry of Education School of Physics and Laboratory of Zhongyuan LightZhengzhou UniversityZhengzhou 450052China School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan 056038China Center for High Pressure Science and Technology Advanced Research Beijing 100094China

The presence of interstitial electrons in electrides endows them with interesting attributes,such as low work function,high carrier concentration,and unique magnetic *** knowledge and understanding of electrides are thus of both scientific and technological ***,we employ first-principles calculations to investigate Mott-insulating Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)electrides with Mn_(5)Si_(3)-type structure,in which half-filled interstitial electrons serve as ions and are *** Mott-insulating property is induced by strong electron correlation between the nearest interstitial electrons,resulting in spin splitting and a separation between occupied and unoccupied *** half-filled antiferromagnetic configuration and localization of the interstitial electrons are critical for the Mott-insulating properties of these *** with that in intermetallic electrides,the orbital hybridization between the half-filled interstitial electrons and the surrounding atoms is weak,leading to highly localized magnetic centers and pronounced correlation ***,the Mott-insulating electrides Ae_(5)X_(3)have very large indirect bandgaps(0.30 eV).In addition,high pressure is found to strengthen the strong correlation effects and enlarge the *** present results provide a deeper understanding of the formation mechanism of Mott-insulating electrides and provide guidance for the search for new strongly correlated electrides.

关键词： intermetallic filled occupied

An innovative classification system for ranking the biological effects of marine aromatic hydrocarbons based on fish embryotoxicity

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Acta Oceanologica Sinica 2024年第6期43卷 153-162页

作者： Ronghui Zheng chao fang Fukun Hong Min Zhang Fulong Gao Yusheng Zhang Jun Bo Key Laboratory of Marine Ecological Conservation and Restoration Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China Observation and Research Station of Coastal Wetland Ecosystem in Beibu Gulf Ministry of Natural ResourcesBeihai 536015China

Petroleum hydrocarbon pollution is a global concern,particularly in coastal *** aromatic hydrocarbons(PAHs) are regarded as the most toxic components of petroleum *** this study,the biomonitoring and ranking effects of petroleum hydrocarbons and PAHs on the marine fish model Oryzias melastigma embryos were determined in the Jiulong River Estuary(JRE) and its adjacent waters in *** results showed that the levels of petroleum hydrocarbons from almost all sites met the primary standard for marine seawater quality,and the concentrations of the 16 priority PAHs in the surface seawater were lower compared with those in other coastal areas worldwide.A new fish expert system based on the embryotoxicity of ***(OME-FES) was developed and applied in the field to evaluate the biological effects of petroleum hydrocarbons and *** selected physiological index and molecular indicators in OME-FES were appropriate biomarkers for indicating the harmful effects of petroleum hydrocarbons and *** outcome of OME-FES revealed that the biological effect levels of the sampling sites ranged from level Ⅰ(no stress) to level Ⅲ(medium stress),which is further corroborated by the findings of nested analysis of variance(ANOVA) *** results suggest that the OME-FES is an effective tool for evaluating and ranking the biological effects of marine petroleum hydrocarbons and *** method may also be applied to evaluate other marine pollutants based on its framework.

关键词： petroleum hydrocarbons polycyclic aromatic hydrocarbons fish expert system integrated biomarker response nested one-way analysis of variance

Synthesis and nitrogen content regulation of diamond in a high-pressure hydrogen-rich environment

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Chinese Physics B 2024年第6期33卷 541-546页

作者：黄国锋陈良超房超 Inner Mongolia Key Laboratory of High-pressure Phase Functional Materials Chifeng UniversityChifeng 024000China Key Laboratory of Material Physics of Ministry of Education School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China

The regulating nitrogen content of diamond in a hydrogen-rich high-temperature and high-pressure(HPHT) growth environment was systematically investigated in this work by developing three growth systems,namely, "FeNi+Ti", "FeNi+G_(3)N_(6)H_(6)",and "FeNi+Ti+C_(3)N_(6)H_(6)".Optical microscopy,infrared spectroscopy,and photoluminescence(PL)spectroscopy measurements were conducted to analyze the spectroscopic characteristics of diamonds grown in these three *** our analysis,it was demonstrated that the presence of hydrogen in the sp^(3) hybrid C-H does not directly affect the color of the diamond and facilitates the increase of the nitrogen-vacancy(NV) center concentration in a highnitrogen-content *** addition,titanium plays an important role in nitrogen removal,while its impact on hydrogen doping within the diamond lattice is *** importantly,by regulating the ratio of nitrogen impurities that coexist in the nitrogen and hydrogen HPHT environment,the production of hydrogenous Ⅱa-type diamond,hydrogenous Ib-type diamond,and hydrogenous high-nitrogen-type diamonds was achieved with a nitrogen content of less than 1 ppm to 1600 ppm.

关键词： diamond HPHT superhard material hydrogen-rich environment

Experimental study of the influencing factors and mechanisms of the pressure-reduction and augmented injection effect by nanoparticles in ultra-low permeability reservoirs

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Petroleum Science 2024年第3期21卷 1915-1927页

作者： Pan Wang Yu-Hang Hu Liao-Yuan Zhang Yong Meng Zhen-Fu Ma Tian-Ru Wang Zi-Lin Zhang Ji-chao fang Xiao-Qiang Liu Qing You Yan Zhang Beijing Key Laboratory of Unconventional Natural Gas Geological Evaluation and Development Engineering China University of Geosciences(Beijing)Beijing100083China School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Petroleum Engineering Technology Research Institute Sinopec Shengli Oilfield CompanyDongying257000ShandongChina Hekou Oil Production Plant Sinopec Shengli Oilfield CompanyDongying257200ShandongChina Petroleum Exploration and Production Research Institute SINOPECBeijing102206China CNPC Engineering Technology R&D Company Limited Beijing102206China

Nanoparticles(NPs)have gained significant attention as a functional material due to their ability to effectively enhance pressure reduction in injection processes in ultra-low permeability *** are typically studied in controlled laboratory conditions,and their behavior in real-world,complex environments such as ultra-low permeability reservoirs,is not well understood due to the limited scope of their *** study investigates the efficacy and underlying mechanisms of NPs in decreasing injection pressure under various injection conditions(25—85℃,10—25 MPa).The results reveal that under optimal injection conditions,NPs effectively reduce injection pressure by a maximum of 22.77%in core *** pressure reduction rate is found to be positively correlated with oil saturation and permeability,and negatively correlated with temperature and ***,particle image velocimetry(PIV)experiments(25℃,atmospheric pressure)indicate that the pressure reduction is achieved by NPs through the reduction of wall shear resistance and wettability *** work has important implications for the design of water injection strategies in ultra-low permeability reservoirs.

关键词： Nanoparticle Pressure reduction Augmented injection Ultra-low permeability reservoir

J-family genes redundantly regulate flowering time and increase yield in soybean

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The Crop Journal 2024年第3期12卷 944-949页

作者： Haiyang Li Zheng Chen Fan Wang Hongli Xiang Shuangrong Liu Chuanjie Gou chao fang Liyu Chen Tiantian Bu Fanjiang Kong Xiaohui Zhao Baohui Liu Xiaoya Lin Guangdong Key Laboratory of Plant Adaptation and Molecular Design/Guangzhou Key Laboratory of Crop Gene Editing/Innovative Center of Molecular Genetics and Evolution School of Life SciencesGuangzhou UniversityGuangzhou 510006GuangdongChina

Soybean(Glycine max)is a short-day crop whose flowering time is regulated by *** longjuvenile trait extends its vegetative phase and increases yield under short-day *** variation in J,the major locus controlling this trait,modulates flowering *** report that the three J-family genes influence soybean flowering time,with the triple mutant Guangzhou Mammoth-2 flowering late under short days by inhibiting transcription of E1-family genes.J-family genes offer promising allelic combinations for breeding.

关键词： Soybean Flowering time Yield J-family genes

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公共教育扩张政策与教育收益率的城乡差异

复旦教育论坛 2024年第3期22卷 92-101页

作者：方超南京财经大学公共管理学院江苏南京210023 浙江省城市治理研究中心浙江杭州311121

基于2019年中国家庭收入调查数据,通过教育收益率的因果性和异质性测量,实证评估了公共教育扩张政策的个体增收效应和收入分配效应。研究结果如下:(1)利用描述性统计法分析发现,公共教育扩张政策对城镇劳动力受教育程度的提升作用高于农... 详细信息

基于2019年中国家庭收入调查数据,通过教育收益率的因果性和异质性测量,实证评估了公共教育扩张政策的个体增收效应和收入分配效应。研究结果如下:(1)利用描述性统计法分析发现,公共教育扩张政策对城镇劳动力受教育程度的提升作用高于农村,因而教育功能具有“城市偏向型”的特征;(2)利用工具变量法纠正内生性问题后,发现公共教育扩张政策对非农户籍具有更强的个体增收效应,农村劳动力的教育收益率高于城镇,大学教育收益率高于义务教育阶段,揭示了公共教育扩张政策的个体增收效应具有“农村导向型”的特征;(3)利用无条件分位数回归及其处理效应模型发现,义务教育改革和高校扩招具有缩小城乡劳动力组内工资收入差距的收入分配功能。

关键词：公共教育扩张政策教育收益率城乡差异收入分配效应无条件处理效应模型

Correction:Current overview on the genetic basis of key genes involved in soybean domestication

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aBIOTECH 2024年第2期5卷 279-279页

作者： Sijia Lu chao fang Jun Abe Fanjiang Kong Baohui Liu Innovative Center of Molecular Genetics and Evolution School of Life SciencesGuangzhou UniversityGuangzhou 510006China Guangzhou Key Laboratory of Crop Gene Editing Guangzhou UniversityGuangzhou 510006China Research Faculty of Agriculture Hokkaido UniversitySapporoHokkaido 060-0808Japan

Correction:aBIOTECH(2022)3:126–139 https://***/10.1007/s42994-022-00074-5 The article‘‘Current overview on the genetic basis of key genes involved in soybean domestication’’,written by Sijia Lu,chao fang,Jun Abe,Fanjiang Kong and Baohui Liu,was originally published Online First without Open *** publication in volume 3,issue 2,pages 126–139 the authors decided to opt for Open Choice and to make the article an Open Access ***,the copyright of the article has been changed to The Authors 2024 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License,which permits use,sharing,adaptation,distribution and reproduction in any medium or format,as long as you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons licence,and indicate if changes were made.

关键词： soybean Open Access