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Catchment environmental change over the 20th Century recorded by sedimentary leaf wax n-alkane δ^(13)C off the Pearl River estuary

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Science China Earth Sciences 2016年第5期59卷 975-980页

作者： XU ShenDong ZHANG Jie wang xianxu JIA GuoDong Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China State Key Laboratory of Marine Geology Tongji University

The compound-specific stable carbon isotope compositions(δ^(13)C) of leaf wax n-alkanes from two short sediment cores recovered off the Pearl River estuary(PRE) were analyzed to check for their capability of indicating decadal scale catchment environmental change. Sedimentary long-chain n-alkanes exhibited an odd-over-even predominance, with a maximum at n-C_(29) or n-C_(31), indicating their leaf wax origin was from vascular plants. The δ^(13)C values of C_(29) and C_(31) n-alkane in all the sediment samples were in the range of -28.8‰ to -31.2‰, consistent with the C_3 plant-dominated vegetation in the Pearl River catchments. The time series of δ^(13)C records from the two cores were comparable and displayed a decreasing trend from the early 20 th century to the end of the 1970s, followed by a reversal in that change leading to continued increase for ca. 15 years. After being corrected for the effect of atmospheric CO_2 rise and δ^(13)C_(atm) decline, the δ^(13)C_(29) records largely retained their raw changing pattern; the post-1980 increase being more conspicuous. The slightly decreasing trend in corrected δ^(13)C records before around 1980 may have been caused by an increase in precipitation, whereas the subsequent increase of δ^(13)C is likely associated with the observed dry climate and/or intensive anthropogenic deforestation. Our results thus demonstrate that leaf wax n-alkanes buried in the sediments off the PRE may well reflect change in the regional climate and/or human activity in the river catchments over the past century.

关键词： Leaf wax n-alkanes compound-specific δ^(13)C values environmental change Pearl River estuary

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Surface chemical microenvironment engineering of catalysts by organic molecules for boosting electrocatalytic reaction

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Chinese Chemical Letters 2024年第8期35卷 15-24页

作者： xianxu Chu Lu wang Junru Li Hui Xu Henan Key Laboratory of Biomolecular Recognition and Sensing College of Chemistry and Chemical EngineeringShangqiu Normal UniversityShangqiu 476000China Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou 213164China

Electrocatalysis is a surface-sensitive process,in which the catalytic activity of electrocatalyst highly re-lates to the surface adsorption/desorption behaviors of the reactants/intermediates/products on the cat-alytically active *** chemical microenvironment engineering via organic molecules functional-ization is a promising strategy to tune the electrocatalytic activity since it can well modify the elec-trode/electrolyte interface and alter the reaction *** this review,we summarize the recent progress of surface microenvironment engineering of electrocatalysts induced by organic molecules func-tionalization,with the special focus on the organic molecule-assisted growth mechanism and unique electronic *** importantly,the applications of organic molecule functionalized catalysts in var-ious electrocatalytic reactions are also systematically summarized,along with a deep discussion on the conclusion and *** work will open a new avenue for the construction and modification of advanced electrocatalysts based on organic molecule-mediated interface engineering.

关键词： Chemical microenvironment engineering Organic molecules Electrocatalysis Functionalization Interface

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高产紧凑红皮小麦新品种农麦156的选育与应用

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浙江农业科学 2024年第6期65卷 1320-1324页

作者：贾瑞宇施昙宋开业黄兴亮王先旭肖群江苏神农大丰种业科技有限公司江苏南京210031 中国种子集团有限公司江苏分公司江苏南京210095

农麦156是江苏神农大丰种业科技有限公司选育的春性中熟红皮小麦品种,该品种的研发主要为了解决传统红皮小麦品种株型散、叶片披、穗数不足、产量低等问题。于2019年通过江苏省审定(苏审麦20190004),2020年通过安徽省引种备案(皖引麦202... 详细信息

农麦156是江苏神农大丰种业科技有限公司选育的春性中熟红皮小麦品种,该品种的研发主要为了解决传统红皮小麦品种株型散、叶片披、穗数不足、产量低等问题。于2019年通过江苏省审定(苏审麦20190004),2020年通过安徽省引种备案(皖引麦2020033),2022年通过浙江省引种备案(浙引种[2022]第001号)。集高产、稳产、紧凑型于一体,具有分蘖力较强、抗寒性较好、株型较紧凑、抗倒性较好、抗病性较好、灌浆快、熟相好、商品性好等特点,适宜在长江中下游冬麦区的江苏和安徽两省淮河以南地区、湖北、浙江、上海、河南信阳地区种植。文章介绍了农麦156的特征特性,并对其选育过程、栽培要点及品种优势进行总结,以期为农麦156推广栽培提供参考,提升其应用价值。

关键词：红皮小麦农麦156 选育过程特征特性品种优势

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Comprehensive overview of genotype distribution and prevalence of human papillomavirus in cervical lesions

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Gynecology and Obstetrics Clinical Medicine 2024年第1期4卷 37-47页

作者： Yuhong Ye Terrel Jones Tiannan wang xianxu Zeng Yang Liu Chengquan Zhao Department of Pathology the First Affiliated HospitalFujian Medical UniversityFuzhouFujianChina Department of Pathology Magee-Womens HospitalUniversity of Pittsburgh Medical CenterPittsburghPennsylvaniaUSA Department of Pathology University of Southern CaliforniaLos AngelesCaliforniaUSA Department of Pathology The Third Affliated Hospital of Zhengzhou UniversityZhengzhouHenanChina Departments of Medicine and Bioengineering University of PittsburghPittsburghPennsylvaniaUSA Department of Bioengineering University of Illinois Urbana-ChampaignUrbanaIllinoisUSA

Acrosscervical squamousandgl and ular lesions,a spectrum of human papillomavirus(HPV)genotypes has been *** review aims to provide a comprehensive summary detailing the distribution and profile of HPV genotypes detected in cervical lesions,leveraging insights from histological and cytological ***-risk HPV(HR-HPV)genotypes exhibit varying degrees of oncogenic potential,with HPV16 and HPV18 identified as the most prevalent and oncogenic *** of HR-HPVgenotypes varies among different degrees of the cervical lesions and varies between squamous andglandular ***16 is predominantly associated with severe lesions(precancers and carcinomas),while HPV18 demonstrates a significantly higher prevalence in endocervical as compared with squamous *** distribution of HR-HPV in severe squamous lesions is complex,involving many HR-HPV genotypes in addition to HPV16,while the distribution of HR-HPV genotypes in endocervical glandular lesions is mainly limited in HPV18 and *** datasets from China have identified the three mostcommon HR-HPVgenotypes in this population as stratified by diagnostic category:HPV52,HPV16,HPV58 in histologically negative cases and cervical intraepithelial neoplasia 1(CIN1);HPV16,HPV52,HPV58 in CIN2/3;HPV16,HPV58,HPV52 or HPV18 in squamous cell carcinoma(SCC);HPV16,HPV18 and HPV52 in endocervical adenocarcinoma in situ(AIS),invasiveadenocarcinoma,as well asmixedsquamous and glandular ***33 is the fourth most common HPVtype in CIN2/3and SCC,whileHPV45occursmore commonly in AIS and adenocarcinoma,compared with squamous *** prevalence and distribution of multiple HR-HPV coinfections vary across different cervical *** clinical significance and pathogenesis of these multiple HR-HPV infections remain uncertain,although recent two large studies demonstrate that multiple HR-HPV infections are not associated with cumulatively higher risk of high-grade cervical squamous lesiondeve

关键词： cervical lesions prevalence

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不同养护制度下粉煤灰混凝土抗硫酸盐冻融循环性能

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水利水电技术（中英文） 2021年第2期52卷 207-214页

作者：王怀义杨桂权王显旭新疆水利水电科学研究院新疆乌鲁木齐830049 新疆水利水电材料工程技术研究中心新疆乌鲁木齐830049

为了揭示养护制度的变化在冻融硫酸盐环境下,对粉煤灰混凝土物理力学性能影响的变化规律,将浸泡不同龄期的粉煤灰混凝土抗压强度进行测试,改变了盐冻前的养护制度,并进行了不同循环后的物理性能试验;同时,对纯水和不同浓度硫酸钠溶液低... 详细信息

为了揭示养护制度的变化在冻融硫酸盐环境下,对粉煤灰混凝土物理力学性能影响的变化规律,将浸泡不同龄期的粉煤灰混凝土抗压强度进行测试,改变了盐冻前的养护制度,并进行了不同循环后的物理性能试验;同时,对纯水和不同浓度硫酸钠溶液低温下冻结过程进行监测。试验研究发现:首先,大掺量粉煤灰混凝土浸泡于硫酸钠溶液中随着龄期延长,抗压强度增长更快,但在高浓度溶液中浸泡60~90 d后强度出现拐点;其次,在非长龄期的硫酸盐溶液中的浸泡,提高了试件后续抵抗此环境下冻融的能力,从300个循环提高至500循环左右;最后,在冻融硫酸盐交互作用下,由于降温速度和完全冻结时长随溶液浓度增大而提高和缩短,最长缩短近200 min左右,从溶液低温化学性态的角度明晰了硫酸盐环境对混凝土抵抗冻融破坏所起的积极作用。

关键词：粉煤灰混凝土冻融硫酸盐养护制度冻结过程

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可压缩边界层的入口合成湍流生成方法

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力学学报 2024年第1期56卷 45-57页

作者：王天孙东郭启龙李辰袁先旭李博中国空气动力研究与发展中心空天飞行空气动力科学与技术全国重点实验室四川绵阳621000

在壁湍流中开展RANS-LES方法混合模拟时,入口处添加合理的湍流脉动能够缩短流场向完全湍流的发展距离,提高数值模拟精度以及节省计算资源.采用SA-IDDES方法对槽道湍流和可压缩湍流边界层开展了数值模拟研究,对比了3种较为常用的合成湍... 详细信息

在壁湍流中开展RANS-LES方法混合模拟时,入口处添加合理的湍流脉动能够缩短流场向完全湍流的发展距离,提高数值模拟精度以及节省计算资源.采用SA-IDDES方法对槽道湍流和可压缩湍流边界层开展了数值模拟研究,对比了3种较为常用的合成湍流方法对流场发展的影响,包括合成湍流生成器(STG)、数字滤波法(DFM)和合成涡方法(SEM);研究了不同合成湍流入口条件下流场壁面摩阻、流场结构、雷诺应力的发展过程,评估了各方法在壁湍流中的表现.其中在不可压槽道湍流和可压缩湍流边界层的模拟中,STG方法展现了较短的摩阻恢复距离,流场结构与雷诺应力发展相比DFM也有一定的优势.在高马赫数湍流边界层的数值模拟中,忽略热力学量脉动可能会降低合成边界层脉动恢复到物理真实脉动的速度.因此,文章进一步基于STG给出的速度脉动,在入口处通过若干强雷诺比拟方法(SRA,GSRA和HSRA)添加热力学脉动量,对比研究了对可压缩湍流边界层流场发展的影响,结果显示是否添加热力学脉动对于流场摩阻和雷诺应力发展影响较小,但对流场中的热力学量影响显著,其中GSRA下流场热力学量恢复得最快.

关键词：合成湍流入口边界条件可压缩性湍流边界层

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基于测井解释的碎屑岩储层成岩作用定量表征:以Q油田下干柴沟组下段为例

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地质科技情报 2018年第1期37卷 240-246页

作者：汪显栩牟中海张国成徐良威西南石油大学地球科学与技术学院成都610500 中国石油青海油田分公司青海敦煌736202

针对Q油田下干柴沟组下段的储层物性和含油性在横向上差异较大的特点,采用钻井取心、岩石薄片等资料对工区储层成岩作用类型及特征进行了定性分析,研究认为工区目的层储层物性横向变化主要由胶结作用和溶解作用共同控制。在此基础上,根... 详细信息

针对Q油田下干柴沟组下段的储层物性和含油性在横向上差异较大的特点,采用钻井取心、岩石薄片等资料对工区储层成岩作用类型及特征进行了定性分析,研究认为工区目的层储层物性横向变化主要由胶结作用和溶解作用共同控制。在此基础上,根据胶结作用、溶解作用的测井响应特征,选取经归一化处理后的GR、SP测井曲线,建立了成岩作用强度定量表征模型,并将各种成岩作用对储层物性综合效应定义为成岩系数。依据成岩系数的大小,将研究区目的层段储层划分为强胶结弱溶解相、中等胶结弱溶解相、中等溶解弱胶结相和强溶解弱胶结相4种类型,定量识别了研究区优质储层,确定了目的层优质储层的平面分布。最后,分析了储层产能和成岩系数之间的关系,验证了该定量表征模型的有效性和实用性。

关键词：成岩作用定量表征岩石薄片测井响应成岩系数

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Swarm intention identification via dynamic distribution probability image

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Chinese Journal of Aeronautics 2024年第10期37卷 380-392页

作者： Yinhan wang Jiang wang Shaoming HE Fei wang Qi wang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

In the realm of decision-making for defense and security applications,it is paramount to swiftly and accurately identify the intentions of incoming *** identification methods predominantly focus on single-target applications and overlook the perturbations introduced by measurement *** this study,we propose a novel concept:the Dynamic Distribution Probability(DDP)image,which is constructed using the estimated state and its covariance *** grayscale pixel value within the image signifies the probability of the presence of the agent within the *** proposed identification scheme integrates the use of Extended Kalman Filter(EKF),Convolutional Neural Network(CNN),Back Propagation(BP)network,and Gated Recurrent Unit(GRU)***,the DDP image is processed through a CNN to distill the formation characteristics,and the estimated swarm state from EKF is inputted into a BP network to deduce the kinematic *** outputs from both networks are summed and subsequently channeled into a GRU network to capture temporal *** numerical simulations and flight experiments are presented to demonstrate the robust anti-noise capability of the proposed scheme compared with conventional methods,as well as its superior training efficiency.

关键词： Intention Identification Kalman filters Convolutional neural networks Swarm intelligence

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尕斯库勒油田N_2~1油藏砂质辫状河储层构型研究

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地质科技情报 2019年第2期38卷 151-160页

作者：吴千然牟中海丁晓军汪显栩王帅陈有锋西南石油大学地球科学与技术学院成都610500 中国石油青海油田分公司研究院甘肃敦煌736202 中国石油西南物探研究院成都610500 中国石油大学(北京)地球科学学院北京102249

尕斯库勒油田已进入高含水期,油水关系复杂,剩余油分布不清,而目前储层构型研究是解决这些问题的主要手段之一。以尕斯库勒油田N■油藏的Ⅰ-5小层作为研究目的层段,采用模式拟合、层次分析等方法分别对单一辫流带级次、心滩级次、心滩... 详细信息

尕斯库勒油田已进入高含水期,油水关系复杂,剩余油分布不清,而目前储层构型研究是解决这些问题的主要手段之一。以尕斯库勒油田N■油藏的Ⅰ-5小层作为研究目的层段,采用模式拟合、层次分析等方法分别对单一辫流带级次、心滩级次、心滩内部级次进行了构型解剖,并提出了井下四级构型界面侧积泥的识别与表征方法,依据河道成因将辫状河道分为泥质充填河道、半泥质充填河道、单一砂体充填河道和多期砂体叠置河道4种类型,在此基础上完善了砂质辫状河的四级构型界面和构型模式;认为研究区辫状河的五级构型界面为泛滥平原泥岩,四级构型界面为泥质充填河道、半泥质充填河道和侧积泥,三级构型界面为落淤层和辫状河道间夹层;研究区只存在一个辫流带,该辫流带顺物源长度为2 326.16 m,切物源长度为2 314.26 m;心滩的平均长度为460 m,平均宽度为285 m,辫状河道的平均宽度为142 m。在此基础上,分析了各级构型界面对剩余油的控制作用。

关键词：砂质辫状河储层构型心滩辫状河道剩余油

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The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

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