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Resin composition: An indicator of oil maturity as revealed by fourier transform ion cyclotron resonance mass spectrometry

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Petroleum Science 2023年第2期20卷 769-775页

作者： tian Liang Zhao-Wen zhan.Guo-Xiang Wang Yan-Rong Zou State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryGuangzhouGuangdong510640China CAS Center for Excellence in Deep Earth Science GuangzhouGuangdong510640China University of Chinese Academy of Sciences Beijing100049China

A pyrolysis experiment was carried out on a Dongying Depression kerogen sample to separate the resin from the oil. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) with a positive-ion detector was used to detect the relative proportional changes in the compounds of the resin. During the whole pyrolysis experiment, the relative ratio of resin exceed 10% of the soluble component at each temperature point. Five compounds were detected from the resin: N1, N1O1, N1O_(2), O1, and O_(2). To research the changes in the proportions of the compounds during pyrolysis clearly, these five compounds were divided into three classes: N1, N1Ox, and Ox. The N1 class has the largest proportion in resin at the beginning of the pyrolysis, while Ox class has the least proportion. And the relationship between the number and the molecular mass of three classes compound was researched. With increasing maturity, the proportion of N1 and the N1Ox class decreased rapidly, while the Ox class increased slowly. Through researching these resin compounds, it was found that an inversion in the proportions of above three compounds appeared at the end of the oil window. At the same time, we found that the DBE and carbon number of resin compounds have changed obviously during the pyrolysis: the DBE increased, while the carbon number decreased significantly. And the details of the change of each compound have been researched. This research extends our knowledge of judging the maturity of crude oil during the pyrolysis through the characteristics of compounds in resin and provides the new index based on resin for the evaluation of thermal evolution stage and hydrocarbon generation capacity of source rocks.

关键词： Resin Pyrolysis FT-ICR MS Heteroatom compound Maturity DBE

Effects of Mg–Ca treatment and Ca treatment on impact toughness and morphology of sulfides in 45MnVS non-quenched and tempered steel

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Journal of Iron and Steel Research International 2024年第11期31卷 2755-2773页

作者： tian-yin zhan.Jun tian Xiang-long Li Li-juan Su Dong Hou tian-peng Qu De-yong Wang Shagang School of Iron and Steel Soochow UniversitySuzhou215137JiangsuChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina

An industrial experiment was conducted at a certain steel plant in China to compare and analyze the effects of Ca treatment and Mg–Ca treatment on inclusions in 45MnVS non-quenched and tempered steel. Through scanning electron microscopy-energy dispersive scanning analysis of the morphology and composition of inclusions, as well as Aspex quantitative analysis of their quantity, type and size, the formation mechanism of MnS–oxide (MnS inclusions with oxide cores) was intensively studied. The influence of sulfide morphology on the impact properties of steel was also analyzed. The results show that the quantity percentage of spindle-shaped sulfides in Ca-treated steel is 19.99%, and that in Mg–Ca-treated steel is 35.38%. Compared with Ca-treated steel, there are more MnS–oxide inclusions in Mg–Ca-treated steel. Controlling the content of Ca and Mg in the oxide core of MnS–oxide inclusion above 10 wt.% and the area ratio below 5 would contribute to the formation of spindle-shaped inclusions after rolling. The mismatch between MnS and oxides decreases with the increase in MgO content in the oxides, which is beneficial to nucleation and precipitation of MnS with this type of oxides as the core. Under the same deformation conditions, the size of sulfide does not affect its aspect ratio. Under the experimental conditions, the inclusion containing a certain amount of MgO can enhance its sulfur capacity, facilitating the formation of composite sulfides. The transverse impact energy of Ca-treated steel is 25.785 J, and that of Mg–Ca-treated steel is 32.119 J. Compared with the traditional Ca-treatment, Mg–Ca treatment can increase the number of spindle-shaped sulfides in the steel, thereby improving the transverse impact toughness of the steel and reducing the anisotropy of the mechanical properties of the material.

关键词： Non-quenched and tempered steel Calcium treatment Magnesium-calcium treatment Sulfide Impact toughness Morphology

Effects of acupuncture on hypothalamic–pituitary–adrenal axis:Current status and future perspectives

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Journal of Integrative Medicine 2024年第4期22卷 445-458页

作者： Jia-yuan Zheng Jing Zhu Yu Wang zhan.zhuang tian Department of Integrative Medicine and Neurobiology School of Basic Medical SciencesState Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceInstitutes of Brain ScienceInstitute of Acupuncture ResearchAcademy of Integrative MedicineShanghai Key Laboratory for Acupuncture Mechanism and Acupoint FunctionShanghai Medical CollegeFudan UniversityShanghai 200032China Department of Human Anatomy School of Integrative MedicineShanghai University of Traditional Chinese MedicineShanghai 201203China

The hypothalamic–pituitary–adrenal(HPA) axis is a critical component of the neuroendocrine system,playing a central role in regulating the body's stress response and modulating various physiological processes. Dysregulation of HPA axis function disrupts the neuroendocrine equilibrium, resulting in impaired physiological functions. Acupuncture is recognized as a non-pharmacological type of therapy which has been confirmed to play an important role in modulating the HPA axis and thus favorably targets diseases with abnormal activation of the HPA axis. With numerous studies reporting the promising efficacy of acupuncture for neuroendocrine disorders, a comprehensive review in terms of the underlying molecular mechanism for acupuncture, especially in regulating the HPA axis, is currently in need. This review fills the need and summarizes recent breakthroughs, from the basic principles and the pathological changes of HPA axis dysfunction, to the molecular mechanisms by which acupuncture regulates the HPA axis. These mechanisms include the modulation of multiple neurotransmitters and their receptors, neuropeptides and their receptors, and microRNAs in the paraventricular nucleus,hippocampus, amygdala and pituitary gland, which alleviate the hyperfunctioning of the HPA *** review comprehensively summarizes the mechanism of acupuncture in regulating HPA axis dysfunction for the first time, providing new targets and prospects for further exploration of acupuncture.

关键词： Acupuncture Electroacupuncture Hypothalamic-pituitary-adrenal axis Mechanism Neurotransmitter microRNA

Characterization of the key aroma compounds in four varieties of pomegranate juice by gas chromatography-mass spectrometry(GC-MS),gas chromatography-olfactometry(GC-O),odor activity value(OAV),aroma recombination,and omission tests

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Food Science and Human Wellness 2023年第1期12卷 151-160页

作者： Cong Lu Yuyu zhan. Ping zhan.Peng Wang Honglei tian College of Food Engineering and Nutritional Science Shaanxi Normal UniversityXi’an 710119China Beijing Key Laboratory of Flavor Chemistry Beijing Technology and Business UniversityBeijing 100048China

P omegranate(Punica granatum L.)has attracted considerable attention in world markets due to its valuable nutrients and highly appreciated sensory *** aroma profiles of 4 varieties of pomegranate juice,including Dahongtian(DP),Jingpitian(JP),Luyudan(LP),and tianhonngdan(TP),were investigated via gas chromatography-mass spectrometry(GC-MS)and gas chromatography-olfactometry(GC-O)analyses.A total of 43 volatile compounds were identified by using *** these compounds,16 were considered as potential aroma-active compounds as detected by *** compounds belonged to the classes of terpinenes,alcohols,and *** volatile compounds were defined as the main contributors to the overall aroma of pomegranate juice due to their high odor activity values(OAVs≥1).Aroma recombination and omission tests confirmed thatβ-myrcene,1-hexanol,and(Z)-3-hexen-1-ol were the key aroma compounds,and limonene,1-octen-3-ol,linalool,and hexanal were important aroma-active compounds in DP samples.

关键词： Pomegranate juice Aroma-active compounds GC-MS GC-O Odor active value(OAV) Omission tests

A study of the effect of local scour on the flow field near the spur dike

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 98-105页

作者： Yu-tian Li Jie-Min zhan.Wing-Hong Onyx Wai Department of Industrial Design School of Industrial Design and Ceramic ArtFoshan UniversityFoshan 528000China Department of Applied Mechanics and Engineering Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China

The flow field near a spur dike such as down flow and horseshoe vortex system(HVS)are susceptible to the topographic changes in the local scouring process,resulting in variation of the sediment transport with *** this study,large eddy simulations with fixed-bed at different scouring stages were conducted to investigate the changes in flow *** results imply that the bed deformation leads to an increase in flow rate per unit area,which represent the capability of sediment transportation by water,in the scour ***,the intensity of turbulent kinetic energy and bimodal motion near the sand bed induced by the HVS were also ***,the peak moments between the two sediment transport mechanisms were ***,understanding the complex feedback mechanism between topography and flow field is essential for the local scour problem.

关键词： Spur dike Local scour Large eddy simulation Down flow Horseshoe vortex system

Spatially-separated and photo-enhanced semiconductor corrosion processes for high-efficient and contamination-free electrochemical nanoimprint lithography

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Science China Chemistry 2022年第4期65卷 810-820页

作者： Hantao Xu Lianhuan Han Jian-Jia Su Zhong-Qun tian Dongping zhan Key Laboratory of Physical Chemistry of Solid Surfaces(PCOSS) Engineering Research Center of Electrochemical Technologies of Ministry of EducationDepartment of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Department of Mechanical and Electrical Engineering School of Aerospace EngineeringXiamen UniversityXiamen 361005China

Free of any thermoplastic or photocuring resists, electrochemical nanoimprint lithography(ECNL) has emerged as an alternative nanoimprint way to fabricate three-dimensional micro/nano-structures(3D-MNSs) directly on a semiconductor wafer by a spatially-confined corrosion reaction induced by the metal/semiconductor contact potential. However, the consumption of electron acceptors in the ultrathin electrolyte between imprint mold and semiconductor wafer will slow down or even cease the corrosion rate. To solve this problem, we change the short-circuited corrosion cell into a spatially-separated primary cell: the imprint mold compacted gallium arsenide(GaAs) wafer in the anodic chamber while the platinum(Pt) plate connected to the imprint mold in the cathodic chamber. Thus, the GaAs corrosion rate will be stabilized in its limiting steady-state current density because of the abundant source of electron acceptors in the catholic chamber. The corrosion processes can be photo-enhanced by white-light illumination. Consequently, both the accuracy and the efficiency are promoted dramatically, which are demonstrated by the excellent performance of the fabricated binary optical elements. Moreover, the contamination problem caused by the electron acceptors is totally avoided. All the results prove that this novel ECNL mode is competitive and prospective in imprinting 3D-MNSs directly on semiconductor wafer.

关键词： nanoimprint lithography electrochemical microfabrication semiconductor corrosion semiconductor microdevices 3D functional micro/nano-structures

Simulation and experiment on prediction of total rice seeds mass in vibrating tray for vacuum plate seeder

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International Journal of Agricultural and Biological Engineering 2019年第5期12卷 81-86页

作者： zhan.Zhao Mingzhi Jin Chunjie tian Fang Qin Institute of Agriculture Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

To improve the seeds pick-up precision of a vacuum plate seeder,it is important to accurately control the relative distance between suction plate and seeds layer in vibrating *** the excitation of reciprocating vibration with a time varying interference in direction angle,the seeds motion is simulated using the discrete element method(DEM).By analyzing the seeds distribution characteristics,it was found that the seeds-mass-per-unit-area(SMA)was approximately plane distributed in the ***,four square areas on the bottom of rectangular tray were divided symmetrically near the four vertices to measure the corresponding SMA respectively,and a monitoring plane model was established to predict the average SMA and total seeds mass in the *** prediction results of DEM simulation showed that the maximum and the mean relative errors were 6.75%and 2.85%.The influences of the normal vector of monitoring plane model and the standard deviation of SMA in four monitoring areas on the prediction errors were analyzed.A method for improving prediction accuracy by using linear regression correction was proposed,and the maximum and the mean relative errors could be reduced to 5.01%and 2.07%.When the tray was vibrated with the frequency of 11 Hz and the amplitude of 4 mm,experiments were carried out on the vacuum plate seeder test-rig.A Kalman filter was adopted to suppress the SMA measurement noise in four monitoring *** results indicated that the maximum and the mean relative errors were 10.2%and 3.46%with the average SMA in range of 0.9-1.5 g/cm2,*** paper can provide a basis for further study on the automatic control of suction plate motion according to the variation of seeds mass in the tray.

关键词： vacuum plate seeder rice seeds total mass prediction method vibrating tray discrete element method

Manipulated microtopography alters plant community development in fragile farm-pastoral transition zone

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Journal of Plant Ecology 2024年第5期17卷 176-188页

作者： Minxuan Gao Yining Wang Yongning Ren Jinyan zhan.tian Xie School of Environment State Key Joint Laboratory of Environmental Simulation and Pollution ControlBeijing Normal UniversityBeijing 100875China Yellow River Estuary Wetland Ecosystem Observation and Research Station Ministry of EducationDongying 257500China

The ecosystems within agro-pastoral transition zones exhibit inherent fragility and heightened susceptibility to climate variability,exacerbated by profound degradation resulting from anthropogenic *** vegetation degradation in these areas precipitates severe soil erosion,presenting formidable challenges for ecological restoration *** utilization of microtopographic structures to mitigate soil erosion and facilitate vegetation recovery stands as a prominent strategy for vegetation restoration within agro-pastoral transition *** the acknowledgment in current restoration practices that the efficacy of microtopography-based restoration is contingent upon slope,aspect and elevation,there remains a notable absence of precise observed information on this *** study,conducted in the Bashang Grassland,a typical agro-pastoral transition zone in northern China,aims to fill the information gap concerning the correspondence between microtopographic structures and restoration *** findings revealed that microtopography has a significant impact on vegetation characteristics,with outcomes varying by *** slopes displayed higher biomass and density compared with sunny slopes and *** microtopography affected community structure,it did not substantially alter species richness,highlighting the critical role of location and pit construction in successful restoration *** study provides insights for the selection,design and assessment of microtopography-based restoration in vulnerable ecosystems.

关键词： community structure microtopography-based restoration plant diversity plant restoration soil erosion

Agro-climatic adaptation of cropping systems under climate change in Shanghai

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Frontiers of Earth Science 2015年第3期9卷 487-496页

作者： Zhuoran LIANG Tingting GU zhan.tian Honglin ZHONG Yuqi LIANG Hangzhou Meteorological Service Hangzhou 310051 China Shanghai Climate Center Shanghai Meteorological Service Shanghai 200030 China Zhejiang Meteorological Service Center Hangzhou 310017 China Department of Geographical Sciences University of Maryland College Park MD 20742 USA Department of Physics and Technology Nanjing Normal University Nanjing 210023 China

Climate change affects the heat and water resources required by agriculture, thus shifting cropping rotation and intensity. Shanghai is located in the Taihu Lake basin, a transition zone for various cropping systems. In the basin, moderate climate changes can cause major shifts in cropping intensity and rotation. In the present study, we integrated observational climate data, one regional climate model, land use maps, and agricultural statistics to analyze the relationship between heat resources and multi-cropping potential in Shanghai. The results of agro-climatic assessment showed that climate change over the past 50 years has significantly enhanced regional agro- climatic resources, rendering a shift from double cropping to triple cropping possible. However, a downward trend is evident in the actual multi-cropping index, caused principally by the increasing costs of farming and limitations in the supply of labor. We argue that improving the utilization rate of the enhanced agro-climatic resources is possible by introducing new combinations of cultivars, adopting more laborsaving technologies, and providing incentives to farmers.

关键词： climate change cropping systems multicropping index double rice Cold Dew wind