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Molecular and Isotopic Characteristics of Mature Condensates from the East China Sea Shelf Basin Using GC×GC-TOFMS and GC-IRMS

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Journal of Earth Science 2019年第2期30卷 376-386页

作者： chao shan Jiaren Ye Alan Scarlett Kliti Grice Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences WA Organic and Isotope Geochemistry Centre and John de Laeter Centrethe Institute for Geoscience ResearchDepartment of Applied ChemistryCurtin University of Technology

In this study, biomarkers, together with stable carbon(δ13 C) and hydrogen(δD) isotopic compositions of n-alkanes have been examined in a suite of condensates collected from the East China Sea Shelf Basin(ECSSB) in order to delineate their source organic matter input, depositional conditions and evaluate their thermal maturity. Previously, GC-MS analyses have shown that all the condensates are formed in oxidizing environment with terrestrial plants as their main source input. No significant differences were apparent for biomarker parameters, likely due to the low biomarker content and high maturity of these condensates. Conventional GC-MS analysis however, may provides limited information on the sources and thermal maturity of complex mixtures due to insufficient component resolution. In the current study, we used comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry(GC×GC-TOFMS) to increase the chromatographic resolution. Compounds such as alkyl cyclohexanes, alkyl cyclopentanes and diamondoids, which can be difficult to identify using conventional GC-MS analysis, were successfully identified using GC×GC-TOFMS. From our analyses we propose two possibly unreported indicators, including one maturity indicator(C5--cyclohexane/C5+-cyclohexane) and one oxidation-reduction environment indicator(alkyl-cyclohexane/alkyl-cyclopentane). Multiple petroleum charging events were proposed as an explanation for the maturity indicators indexes discrepancy between methyl-phenanthrene index(MPI) and methyl-adamantane index(MDI). In addition, the stable isotopic results show that condensates from the Paleogene have significantly higher positive δ13 C values of individual n-alkanes than the Neogene samples. Based on δD values, the samples can be divided into two groups, the differences between which are likely to be attributed to different biosynthetic precursors. Variation within each group can likely be attributed to vaporization.

关键词： condensate biomarker characteristic source information GC×GC-TOFMS GC-IRMS

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发芽糙米特征营养、食味品质提升及功能性评价研究进展

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食品科学 2025年第1期46卷 284-292页

作者：任传英洪滨张珊袁迪冯俊然山珊张竞一管立军李波黄文功卢淑雯黑龙江省农业科学院食品加工研究所黑龙江省食品加工重点实验室黑龙江省全谷物营养食品工程技术研究中心黑龙江哈尔滨150086 黑龙江省农业科学院农产品质量安全研究所黑龙江哈尔滨150086

发芽糙米作为一种全谷物,保留了完整的皮层和胚,集中了大部分营养素和功能性活性物质,但由于皮层纤维结构致密,蒸饭过程中阻碍了吸水速率、吸水量和淀粉糊化,与大米相比,其蒸煮性和食用品质较差,且难以同煮同熟,因此一直以来未被广大消... 详细信息

发芽糙米作为一种全谷物,保留了完整的皮层和胚,集中了大部分营养素和功能性活性物质,但由于皮层纤维结构致密,蒸饭过程中阻碍了吸水速率、吸水量和淀粉糊化,与大米相比,其蒸煮性和食用品质较差,且难以同煮同熟,因此一直以来未被广大消费者接受。本文综述糙米发芽的生理代谢反应及发芽过程中营养成分、活性成分和食味品质的变化,总结发芽糙米胁迫富集γ-氨基丁酸(γ-aminobutyric acid,GABA)技术和发芽糙米的功能特性研究现状。糙米发芽过程中,多种生物活性物质在酶促反应下富集,尤其是特征成分GABA含量显著提升。多种逆境胁迫均可通过改变Ca^(2+)、H^(+)或底物水平促进GABA富集,一些预处理技术可进一步提升发芽糙米的食味品质。GABA与其他营养成分和活性成分发挥协同作用,赋予发芽糙米抗高血脂、抗高血糖、保护心脏、改善睡眠、抗炎和抗氧化等一系列功效与作用。

关键词：发芽糙米特征营养食味品质功能性

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Temporal and spatial variation of nitrogen and phosphorus and eutrophication assessment for a typical arid river - Fuyang River in northern China

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Journal of Environmental Sciences 2017年第5期29卷 41-48页

作者： Wenqiang Zhang Xin Jin Dong Liu chao Lang Baoqing shan State Key Laboratory on Environmental Aquatic Chemistry Research Center for Eco-Environmental Science Chinese Academy of Science Beijing 100085 China. University of Chinese Academy of Science Beijing 100049 China Hebei University of Engineering Hebei 056038 China

Based on water quality surveys over 2 years （July to December, in 2014 and 2015） in a typical arid fiver in northern China the Xingtai segment of the Yuyang River basin - the variation of nitrogen （N） and phosphorus （P） was analyzed. The extent of water eutrophication of this segment was also assessed using a universal index formula for eutrophic evaluation and a logarithmic power function. The results showed that the average concentration of total N （TN） was 27.2 mg/L （NH3-N, 63.5% ）, total P （TP） was 2.0 mg/L （solution reactive phosphorus, 68.8%）. Temporal and spatial variations of N and P in this segment were observed. Concentrations of N and P in the arid season were higher than those in the rainy season. Spatially, the N and P concentrations followed the same trend; i.e., higher in the city segment than in the suburbs, and decreasing along the river. The water eutrophication in the studied segment reached extremely high levels at all times （eutrophication index ≥76.3）. Spatially, its trend was clearly linked with N and P. Water shortage, pollution accumulation and a weak self-purification function are the main reasons for the prominent eutrophication in this segment.

关键词： Arid river Eutrophication Nitrogen Phosphorus Northern China

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Wake flow and vortex structures behind emergent vegetation patches elongated in the longitudinal direction

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Journal of Hydrodynamics 2021年第6期33卷 1148-1161页

作者： Zi-jian Yu Yu-qi shan chao Liu Xing-nian Liu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China Department of Civil and Environmental Engineering University of AlbertaEdmontonCanada Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu 610065China

In natural rivers,patches of vegetation generally expand over their steady wake region in the streamwise direction,forming elongated patches with length(L)greater than their width(b).This paper studies how the wake flows and the vortices develop as the emergent patches expand their length in the streamwise *** patches are modeled with the same width but different lengths in laboratory *** the patches,the steady wake region(L_(w))is not related to the width-related flow blockage(C_(d)ab),where C_(d) is the drag coefficient,a is the vegetation ***,L_(w) is related to the length-related flow blockage(C_(d)aL).On this basis,a model is proposed for predicting L_(w),which is in good agreement with the *** a patch becomes denser and/or longer(as C_(d)aL increases),the steady wake region becomes shorter(L_(w) decreases),and vortices are observed closer to the patch trailing edge,producing a turbulence of a greater magnitude beyond L_(w).When the flow blockage increases to the limit(C_(d)aL>8),the Karman vortices are observed directly behind the porous *** results can be used to explain the longitudinal elongation of the vegetation patches in the field.

关键词： Velocity profiles turbulent kinetic energy wakes vortex streets vegetation patch

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A Double-Stage Surrogate-Based Shape Optimization Strategy for Blended-Wing-Body Underwater Gliders

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China Ocean Engineering 2020年第3期34卷 400-410页

作者： LI Cheng-shan WANG Peng QIU Zhi-ming DONG Hua-chao School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

In this paper,a Double-stage Surrogate-based Shape Optimization(DSSO)strategy for Blended-Wing-Body Underwater Gliders(BWBUGs)is proposed to reduce the computational *** this strategy,a double-stage surrogate model is developed to replace the high-dimensional objective in shape ***,several First-stage Surrogate Models(FSMs)are built for the sectional airfoils,and the second-stage surrogate model is constructed with respect to the outputs of ***,a Multi-start Space Reduction surrogate-based global optimization method is applied to search for the *** order to validate the efficiency of the proposed method,DSSO is first compared with an ordinary One-stage Surrogate-based Optimization strategy by using the same optimization ***,the other three popular surrogate-based optimization methods and three heuristic algorithms are utilized to make *** indicate that the lift-to-drag ratio of the BWBUG is improved by 9.35%with DSSO,which outperforms the comparison ***,DSSO reduces more than 50%of the time that other methods used when obtaining the same level of ***,some considerations of the proposed strategy are further discussed and some characteristics of DSSO are identified.

关键词： shape optimization double-stage surrogate model kriging blended-wing-body underwater glider lift-to-drag ratio

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Improved tensile properties of Al_(0.5)CoCrFeNi high-entropy alloy by tailoring microstructures

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Rare Metals 2021年第9期40卷 2508-2513页

作者： Si-Zhe Niu Hong-chao Kou Jun Wang Jin-shan Li State Key Laboratory of Solidiﬁcation Processing Northwestern Polytechnical UniversityXi’an 710072China

The effect of heat treatment on microstructure and tensile properties of as-cast Al_(0.5)CoCrFeNi high-entropy alloy was investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM) equipped with energy-dispersive spectroscopy(EDS), and tensile *** results show that heat treatment strongly affects the microstructure, particularly the morphology of bcc phases,and improves tensile properties. Microstructure analysis reveals that rod-shaped and elliptoid phases appear in the matrix after heat treatment at 1150 ℃. Besides, under850 ℃ heat-treated condition, ultimate tensile strength increases by about 60% without sacrificing much plasticity,which can be attributed to the content of bcc phases and fine precipitates dispersed in the dendrites. For other heattreated conditions, tensile ductility increases by at least30%, especially 60% for heat treatment at 450 ℃, and strength also improves. Fracture analysis indicates that the fracture mode of heat treatment at 850 ℃ is a mixture of quasi-cleavage and ductile fracture, while the other heattreated conditions show the mode of ductile fracture.

关键词： High-entropy alloys Heat treatment Microstructure Tensile properties

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Long-term follow-up of cumulative incidence of hepatocellular carcinoma in hepatitis B virus patients without antiviral therapy

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World Journal of Gastroenterology 2021年第11期27卷 1101-1116页

作者： Xiao-Yan Jiang Bing Huang Dan-Ping Huang Chun-shan Wei Wei-chao Zhong De-ti Peng Fu-Rong Huang Guang-Dong Tong Department of Gastroenterology Shenzhen Traditional Chinese Medicine HospitalThe Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033Guangdong ProvinceChina Department of Hepatology Shenzhen Traditional Chinese Medicine HospitalThe Fourth Clinical Medical College of Guangzhou University of Chinese MedicineShenzhen 518033Guangdong ProvinceChina

BACKGROUND China has a high prevalence of hepatitis B virus(HBV),but most chronic hepatitis B(CHB)patients do not receive standardized antiviral *** are few relevant reports addressing the outcomes of the large number of CHB patients who do not receive antiviral *** To observe the outcomes of long-term follow-up of patients with CHB without antiviral *** This study included 362 patients with CHB and 96 with hepatitis B cirrhosis without antiviral treatment and with only liver protection and anti-inflammatory treatment from 1993 to *** median follow-up times were 10 and 7 years,respectively.A total of 203 CHB and 129 hepatitis B cirrhosis patients receiving antiviral therapy were selected as the control *** median follow-up times were 8 and 7 years,***-Meier curves were used to analyze the cumulative incidence of hepatocellular carcinoma(HCC),and the Cox regression model was used to analyze the risk factors for *** Among the patients in the non-antiviral group,16.9%had spontaneous decreases(HBeAg)*** the antiviral group,87.2%of patients had undetectable HBV DNA,and 52%showed HBeAg *** CHB and hepatitis B cirrhosis patients,the cumulative incidence rates of HCC were 14.9%and 53.1%,respectively,in the non-antiviral group and were 10.7%and 31.9%,respectively,in the antiviral *** was no difference between the two groups regarding the CHB patients(P=0.842),but there was a difference between the groups regarding the hepatitis B cirrhosis patients(P=0.026).The cumulative incidence rates of HCC were 1.6%and 22.3%(P=0.022)in the groups with and without spontaneous HBeAg seroconversion,*** incidence rates of HCC among patients with and without spontaneous declines in HBV DNA to undetectable levels were 1.6%and 19.1%,respectively(P=0.051).There was no difference in the cumulative incidence of HCC between the two groups regarding the patients with drug-resistan

关键词： Chronic hepatitis B Anti-inflammatory therapy Hepatoprotective therapy Cumulative incidence Hepatocellular carcinoma Antiviral therapy

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Theoretical characterization of hole mobility in BTBPD

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Chinese Chemical Letters 2013年第10期24卷 945-948页

作者： tie-chao Jiang Zhong-Yu Wang Bei-Bei Du shan-shan Zhao China-Japan Union Hospital of Jilin University Jilin University State Key Laboratory of Supramolecular Structure and Materials Jilin University

（ E）-5,5＇-Bis（ 5-（ benzo[ b ]thiophen- 2-yl ）thiophen-2-yl ）-1,1＇-bis（ 2-ethylhexyl ）-[ 3,3＇-bipyrrolylidene ]- 2,2＇（1H, l＇H）-dione （BTBPD） has been reported by Zhang and co-workers. To further understand the charge-transporting nature of BTBPD, the density-functional theory （DFF） and the Marcus charge transfer theory were performed. The character of the frontier molecular orbitals, reorganization energies and transfer integrals in different directions were considered in details. The results revealed that the BTBPD has high hole transport efficiency （μ = 0.29 cm2 V-1 s-1 ）. The intermolecular π-π interaction and S...S interaction provide the holes transport channels.

关键词： BTBPD DFT Marcus charge transport theory

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Enhanced precipitation responses over the tibetan Plateau following future Tambora-size volcanic eruption

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Advances in Climate Change Research 2024年第5期15卷 845-858页

作者： Xin-Jun GAN Lin-shan YANG Meng ZUO Fei LIU chao-chao GAO College of Environmental and Resource Science Zhejiang UniversityHangzhou 310058China Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control Hangzhou 310058China State Key Laboratory of Severe Weather and Institute of tibetan Plateau Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China School of Atmospheric Sciences&Key Laboratory of Tropical Atmosphere Ocean System Ministry of Education Sun Yat-sen UniversiyZhuhai 519082China Southern Marine Science and Engineering Guangdong Laboratory Sun Yat-sen UniversityZhuhai 519082China

Hydroclimate over the tibetan Plateau(TP)notably influences the eco-environment of the Northern *** its high elevation and complex topography,the climate in the TP shows a high sensitivity to anthropogenic warming and volcanic-induced *** mechanism by which a future volcanic or similar radiative perturbation affects precipitation in the TP under an anthropogenic warming climate must be addressed not only to enable regional adaptation but deepen our understanding of how a climate system evolves under such a dual ***,based on the Community Earth System Model version 1.2 and ensemble simulations under pre-industrial and RCP8.5 scenarios,we showed that a Tambora-sized volcanic perturbation led to severe rainfall reduction over the south TP in the following summer(June-August).Evaporation response accounted for a minor and relatively constant share of precipitation reduction following the Clausius-Clapeyron scaling,whereas dynamic processes triggered an El Nino-like response in the eastern equatorial Pacific,which suppressed the Walker and Hadley circulation and contributed to drying *** warming renders the post-Tambora hydroclimate responses with 30%higher severity as a result of the increased climatological moisture content and intensified El Nino response,which enhanced hydroclimate sensitivity and attenuated monsoon *** results illustrate the amplification effect of global warming on the plateau's hydroclimate responses to external forcings,which may add another layer of uncertainty on climate adaptation in this already complex region.

关键词： tibetan Plateau The community earth system model Hydrological response Tambora eruption El Nino

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Effects of Phosphorus Application in Different Soil Layers on Root Growth, Yield, and Water-Use Efficiency of Winter Wheat Grown Under Semi-Arid Conditions

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Journal of Integrative Agriculture 2014年第9期13卷 2028-2039页

作者： KANG Li-yun YUE shan-chao LI Shi-qing Sate Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau Northwest Agriculture and Forestry University College of Forestry Northwest Agriculture and Forestry University

Deep phosphorus application can be a usefull measure to improve crops＇ performance in semi-arid regions, but more knowledge of both its general effects and effects on specific crops is required to optimize treatments. Thus, the aims of this study were to evaluate the effects of phosphorus（P） application at different soil layers on root growth, grain yield, and water-use efficiency（WUE） of winter wheat grown on the semi-arid Loess Plateau of China and to explore the relationship between root distribution and grain yield. The experiment consisted of four P treatments in a randomized complete block design with three replicates and two cultivars： one drought-sensitive（Xiaoyan 22, XY22） and one drought-tolerant（Changhan 58, CH58）. The four P treatments were no P（control, CK）, surface P（SP）, deep P（DP）, and deep-band P application（DBP）. CH58 produced larger and deeper root systems, and had higher grain yields and WUE, under the deep P treatments（DP and DBP） than under SP, clearly showing that deep P placement had beneficial effects on the drought-tolerant cultivar. In contrast, the grain yield and root growth of XY22 did not differ between DP or DBP and SP treatments. Further, root dry weight（RW） and root length（RL） in deep soil layer（30-100 cm） were closely positively correlated with grain yield and WUE of CH58（but not XY22）, highlighting the connections between a well-developed subsoil root system and both high grain yield and WUE for the drought-tolerant cultivar. WUE correlated strongly with grain yield for both cultivars（r=0.94, P〈0.001）. In conclusion, deep application of P fertilizer is a practical and feasible means of increasing grain yield and WUE of rainfed winter wheat in semi-arid regions, by promoting deep root development of drought-tolerant cultivars.

关键词： water stress phosphorus application soil layers grain yield root growth water-use efficiency

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