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A Tri-mode of Mock-Walker Cells

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Advances in Atmospheric Sciences 2024年第4期41卷 671-679页

作者： Han QIN ji nie Zhiyong MENG Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China China Meteorological Administration Tornado Key Laboratory Foshan 528061China

This work uses cloud-resolving simulations to study mock-Walker cells driven by a specified sea surface temperature(SST).The associated precipitation in the mock-Walker cells exhibits three different modes,including a single peak of precipitation over the SST maximum(mode 1),symmetric double peaks of precipitation straddling the SST maximum(mode 2),and a single peak of precipitation on one side of the SST maximum(mode 3).The three modes are caused by three distinct convective activity center migration *** indicate that the virtual effect of water vapor plays an important role in differentiating the three *** the SST gradient is large,the virtual effect may be strong enough to overcome the temperature effect,generating a low-level low-pressure anomaly below the ascending branch of the Walker cell off the *** results here highlight the importance of the virtual effect of water vapor and its interaction with convection and large-scale circulation in the Walker circulation.

关键词： Walker circulation cloud-resolving simulation virtual effect

A Two-plume Convective Model for Precipitation Extremes

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Advances in Atmospheric Sciences 2021年第6期38卷 957-965页

作者： Zihan YIN Panxi DAI ji nie Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijing 100029China

In the study of diagnosing climate simulations and understanding the dynamics of precipitation extremes,it is an essential step to adopt a simple model to relate water vapor condensation and precipitation,which occur at cloudmicrophysical and convective scales,to large-scale *** simple models have been proposed;however,improvement is still needed in both their accuracy and/or the physical ***,we propose a two-plume convective model that takes into account the subgrid inhomogeneity of precipitation *** convective model has three components,i.e.,cloud condensation,rain evaporation,and environmental descent,and is built upon the zero-buoyancy approximation and guidance from the high-resolution *** against the CMIP5 climate simulations,the convective model shows large improvements in reproducing precipitation extremes compared to previously proposed ***,the two-plume convective model better captures the main physical processes and serves as a useful diagnostic tool for precipitation extremes.

关键词： precipitation extremes convective model rain evaporation environmental descent

Evaluation indices of sour flavor for apple fruit and grading standards

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Journal of Integrative Agriculture 2018年第5期17卷 994-1002页

作者： YAN Zhen ZHENG Li-jing nie ji-yun LI Zhi-xia CHENG Yang Laboratory of Quality & Safety Risk Assessment for Fruit (Xingcheng) Ministry of Agriculture/Institute of Pomology Chinese Academy of Agricultural Sciences Xingcheng 125100 P.R. China Beijing Agriculture Technology Extension Station Beijing 100029 P.R. China

In order to establish grading standards of evaluation indices for sour flavor of apples, 10 indices of samples from 106 apple cultivars were tested, including： malic acid（Mal）, oxalic acid（Oxa）, citric acid（Cit）, lactic acid（Lac）, succinic acid（Suc）, fumaric acid（Fum）, total organic acids（To A, the sum of the six organic acids tested）, titratable acid（TiA）, acidity value（AcV）, and pH value. For most of the cultivars studied（85.8%）, the order of the organic acid contents in apples was Mal〉Oxa〉Cit〉Lac〉Suc〉Fum. Mal was the dominant organic acid, on average, accounting for 94.5% of To A. Among the 10 indices, the dispersion of pH value was the smallest with a coefficient of variation of only 8.2%, while the coefficients of variation of the other nine indices were larger, ranging between 31 and 66%. There were significant linear relationships between Mal and two indices（ToA and AcV） as well as between ToA and AcV. There were significant logarithmic relationships between pH value and four indices： Mal, TiA, ToA, and AcV. All the equations had very high fitting accuracy and can be used to accurately predict related indices. According to this study, Mal, ToA, and AcV of apple were normally distributed, TiA was close to normally distributed, whereas pH value had a skewed distribution. Using the fitted normal distribution curves, the grading standards of Mal, TiA, ToA, and AcV were established. The grading node values of pH value were obtained using the logarithmic relationship between pH value and Mal. The grading standards of these five indices can be used to evaluate the sour flavor of apple. This study provides a scientific basis for evaluating apple flavor and selecting apple cultivars.

关键词： apple organic acid sour flavor evaluation indices grading standard

Climate change attribution of the 2021 Henan extreme precipitation: Impacts of convective organization

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Science China Earth Sciences 2022年第10期65卷 1837-1846页

作者： Han QIN Wei YUAN Jun WANG Yang CHEN Panxi DAI Adam HSOBEL Zhiyong MENG ji nie Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China Aviation Meteorological Center Civil Aviation Administration of ChinaBeijing 100621China Key Laboratory of Regional Climate-Environment for Temperate East Asia(RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Department of Atmospheric Science School of Earth SciencesZhejiang UniversityHangzhou 310027China Department of Applied Physics and Applied Mathematics and Lamont-Doherty Earth Observatory Columbia University

In this study, we investigate the climate attribution of the 21·7 Henan extreme precipitation event. A conditional storyline attribution method is used, based on simulations of the event with a small-domain high-resolution cloud-resolving model. Large-scale vertical motion is determined by an interactive representation of large-scale dynamics based on the quasigeostrophic omega equation, with dynamical forcing terms taken from observation-based reanalysis data. It is found that warming may lead to significant intensification of both regional-scale(10–14% K, depending on convective organization) and station-scale precipitation extremes(7–9% K^(-1)). By comparing clustered convection organized by a localized surface temperature anomaly and squall-line convection organized by vertical wind shear, we further explored how convective organization may modify precipitation extremes and their responses to warming. It is found that shear convective organization is much more sensitive to large-scale dynamic forcing and results in much higher precipitation extremes at both regional and station scales than unorganized convection is. The clustered convection increases station-scale precipitation only slightly during heavy precipitation events. For regional-scale extreme precipitation sensitivity, shear-organized convection has a larger sensitivity by 2–3% Kthan that of unorganized convection, over a wide temperature range, due to its stronger diabatic heating feedback. For the station-scale extreme precipitation sensitivity, no systemic dependence on convective organization is found in our simulations.

关键词： Extreme precipitation Global warming Climate change attribution Convective organization Hourly precipitation

Multi-mycotoxin exposure and risk assessments for Chinese consumption of nuts and dried fruits

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Journal of Integrative Agriculture 2018年第7期17卷 1676-1690页

作者： WANG Yu-jiao nie ji-yun YAN Zhen LI Zhi-xia CHENG Yang Saqib Farooq Institute of Pomology Chinese Academy of Agricultural Sciences Laboratory of Quality and Safety Risk Assessment for Fruit (Xingcheng) Ministry of Agriculture Quality Inspection and Test Center for Fruit and Nursery Stocks (Xingcheng) Ministry of Agriculture

In this study, 15 mycotoxins were detected in 233 nut and dried fruit samples from China. The 15 mycotoxins included aflatoxins （AFs： AFB1, AFB2, AFG1 and AFG2）, trichothecene toxins （TCs： T-2, ZEA, ENA, ENA1, ENB, ENB1 and BEA）, Alternaria toxins （ATs： TEN, AOH and AME） and ochratoxin A （OTA）. The mycotoxins were detected in 47.6% of the samples and all 15 of the mycotoxins were found. Two samples were positive for AFB1 and exceeded the maximum tolerable levels allowed in China. The contamination levels of the mycotoxins found in nuts, dried jujubes, raisins, dried figs and dried Iongans were in the ranges of 0.1-462.7, 0.2-247.3, 0.8-10.1,0.2-384.1 and 0.1-89.2 μg kg^-1, respectively. Dried figs （80.0%） had the highest incidence of mycotoxins, followed by dried Iongans （60.0%）, dried jujubes （57.1%）, nuts （43.6%） and raisins （26.7%）. The estimated daily intake （EDI） values of each individual mycotoxin and all of the mycotoxins collectively were calculated by both the deterministic approach （DA） and the probability approach （PA）. For risk characterization, dietary exposure to TCs, ATs and OTA through consumption of nuts and dried fruits according to both approaches, showed no health risk to Chinese adults by exposure to either individual mycotoxins or in combination. To the best of our knowledge, this is the first work in which risk assessment of multimycotoxins is performed, specifically including the emerging ENNs and BEA, in nuts and dried fruits of China.

关键词： mycotoxins risk assessment deterministic analysis probabilistic analysis nuts dried fruits

Evaluation of sugar and organic acid composition and their levels in highbush blueberries from two regions of China

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Journal of Integrative Agriculture 2020年第9期19卷 2352-2361页

作者： ZHANG jia nie ji-yun LI jing ZHANG Hui LI Ye Saqib FAROOQ Syed Asim Shah BACHA WANG jie Laboratory of Quality&Safety Risk Assessment for Fruit(Xingcheng) Ministry of Agriculture and Rural Affairs/Institute of PomologyChinese Academy of Agricultural SciencesXingcheng 125100P.R.China College of Horticulture Qingdao Agricultural UniversityQingdao 266109P.R.China Institude of Crop Science Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

Sweet and sour are the most important taste of blueberries,and they are produced by sugar and acid,*** contributions to the taste depend not only on the levels of sugar and acid,but also on the types and relative proportions of sugar and ***,it is very important to evaluate the composition and levels of sugar and acid in *** differences and variety diversity also affect the sugar and acid characteristics of ***,this study selected two main producing regions in northern China(Weihai and Yingkou)to examine the sugar and acid characteristics of 11 common blueberry *** indexes measured included soluble sugars,organic acids,soluble solid content and titratable *** results showed that glucose and fructose were the major sugars,and citric acid and quinic acid were the major organic *** analysis showed that glucose,fructose,and sucrose were positively correlated with total sugar content;the citric acid content was positively correlated with the titratable acidity and total organic *** acidity,glucose,fructose,sucrose,total sugar content,citric acid,shikimic acid and total acid content of the blueberries varied significantly between regions(P<0.05).In general,compared with Weihai blueberries,Yingkou blueberries had higher sugar content and lower acid *** results of this study may provide useful references for the evaluation of sweet and sour flavors and cultivar selection of blueberries.

关键词： blueberry sugar organic acid level evaluation

杜甫引《易》诗的学术属性及中唐前象数易学背景

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周易研究 2019年第4期 77-84页

作者：聂济冬山东大学儒学高等研究院山东济南250100

通常认为,唐代儒玄合流,王弼《周易注》通行天下。在这种背景下,杜甫的易学接受面向应该是王弼义理之学,但考察过杜甫引《易》诗之后,却发现其中少有王弼义理,而多用汉儒易学。这种貌似不合拍的现象,并非是说杜甫不通王弼义理,而是反映... 详细信息

通常认为,唐代儒玄合流,王弼《周易注》通行天下。在这种背景下,杜甫的易学接受面向应该是王弼义理之学,但考察过杜甫引《易》诗之后,却发现其中少有王弼义理,而多用汉儒易学。这种貌似不合拍的现象,并非是说杜甫不通王弼义理,而是反映了杜甫引《易》之诗蕴含着儒家道德旨归,秉持了汉儒易学的政治思维。同时,杜诗中王弼义理的缺失,也反映出中唐以前象数易学的接受、传播态势未曾寂寥;而汉易学不绝如缕地传播,为杜甫引《易》诗采用汉儒易学思维提供了可能性。

关键词：杜甫引《易》诗象数易学政治思维

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谶纬“河图”、“洛书”中神话意象诠释

周易研究 2011年第3期 76-81页

作者：聂济冬山东大学文史哲研究院山东济南250100

谶纬"河图"、"洛书"神话,是在原始思维的集体记忆的基础上,发挥玄想,以象立意。根据受众的不同,可以将其分为政治、民生两类。从诠释发生的角度、诠释方式和诠释功能而言,谶纬"河图"、"洛书"与《周易》有异曲同工之妙。谶纬"河图"、"洛... 详细信息

谶纬"河图"、"洛书"神话,是在原始思维的集体记忆的基础上,发挥玄想,以象立意。根据受众的不同,可以将其分为政治、民生两类。从诠释发生的角度、诠释方式和诠释功能而言,谶纬"河图"、"洛书"与《周易》有异曲同工之妙。谶纬"河图"、"洛书"中的神话意象和意境,看似为非理性的构思,实为理性智慧的阐发,它阐释的重点是儒家仁政学说和民本思想,展现了汉儒的普世精神和政治诉求。

关键词：谶纬 “河图”“洛书” 神话政治理性

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北宋《盐铁论》接受特征与学术倾向

齐鲁学刊 2017年第6期 112-119页

作者：聂济冬山东大学儒学高等研究院山东济南250100

《盐铁论》是据汉昭帝时期盐铁会议纪要所作的再创作,它以"春秋"笔法反映了西汉中期儒生与文法吏之间的政治对立,成为后世王霸之争、义利之辨的政治标本。北宋时期,在偃武右文、寻求变革的时代背景下,士人群体对于《盐铁论》的接受呈现... 详细信息

《盐铁论》是据汉昭帝时期盐铁会议纪要所作的再创作,它以"春秋"笔法反映了西汉中期儒生与文法吏之间的政治对立,成为后世王霸之争、义利之辨的政治标本。北宋时期,在偃武右文、寻求变革的时代背景下,士人群体对于《盐铁论》的接受呈现出多元特征。早期多倾向于文学意象、历史典故层面的接受,同时亦注意《盐铁论》中资政类目的借鉴。在熙宁年间,以司马光为首的保守士人借古喻今,以书中"贤良文学"、"桑弘羊"的符号表象,诠释自己的政治见解,映射批评王安石变法的弊端。北宋关于《盐铁论》的诠释、接受特征,体现出彼时学术的演变倾向、发展脉络。

关键词：《盐铁论》北宋接受特征学术倾向