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作者： David andreea 浙江师范大学

学位级别：硕士

香根草油是从香根草(Vetiveria zizanioides(L.)Nash)的根中提取的一种植物精油,在香料工业中常被大量用作主要的调香成分,而且在食品工业中也可用作调味剂。由于香根草油用途广泛,且具有抗氧化、抗菌、消炎等生物活性,近年来有大量有... 详细信息

香根草油是从香根草(Vetiveria zizanioides(L.)Nash)的根中提取的一种植物精油,在香料工业中常被大量用作主要的调香成分,而且在食品工业中也可用作调味剂。由于香根草油用途广泛,且具有抗氧化、抗菌、消炎等生物活性,近年来有大量有关其提取技术和成分分析的研究报道,研究热点围绕如何降低生产成本及环境污染,以满足日益增长的市场需求。二氧化碳膨胀乙醇(CO expanded ethanol,CXE)是一种环境友好的新型绿色溶剂,提取的效率及成本与传统蒸馏法相当,并高于超临界二氧化碳萃取。本研究经优化得到最优的工艺操作条件,与水蒸汽蒸馏工艺和超临界流体萃取工艺进行比较,评估新工艺的特点及可行性。由于香根草的化学成分复杂,香气及功效成分含量低,传统方法很难进行分离鉴定。本研究对香根草油进行了二级分子蒸馏,去除了大部分非挥发成分,显著增强色谱峰分离度,对有效成分进行了富集,结合GC-MS精油的组成分析,鉴定主要的特征性香气成分、抗菌成分及抗氧化成分,为制定产品质量标准提供理论依据,同时考察分子蒸馏用于精制香根油的可行性。CXE是一种混合流体,由主体的极性溶剂乙醇和压缩的超临界或亚临界二氧化碳组成,二氧化碳会导致溶剂的体积膨胀,对其溶解能力和传质效率等性能产生了显著影响。CXE流体对各种溶质均具有很强的溶解能力,其低温和隔氧的操作条件尤其适用于易氧化和不耐热的组分的提取。通过与水蒸汽蒸馏(HD)、间接蒸气蒸馏(IVD)及超临界流体萃取(SFE)等传统方法进行对比,综合评测了CXE萃取获得的香根草油的化学组成、抗菌及抗氧化活性。由于根系材料提取油的化学组成比植物的其他部位提取物更为复杂,因此需要进一步的精炼过程。分子蒸馏是一种在真空和低温条件下进行的分离富集技术,比较适用于热敏性的精油组分。两级分子蒸馏是一种有效的预处理方法,能使各组分有效分离,提供更可靠的成分鉴定,并对各馏分的抗氧化活性进行了测定。主要研究内容如下:(1)水蒸汽蒸馏、间接蒸气蒸馏和超临界流体萃取等传统方法提取香根草油的研究。结果表明提取时间、物料粒径及浸泡时间对香根草精油的得率有显着影响。水蒸汽蒸馏和间接蒸汽蒸馏法的提取时间为12-18小时,而超临界流体萃取的提取时间仅为2小时。HD和IVD的油得率为0.6%(w/w),SFE油得率约为0.5%(w/w)。(2)采用由极性溶剂(乙醇)和压缩的CO形成的CXE进行了香精油的绿色提取,并与纯乙醇提取进行了对比。采用基于中心组合设计(CCD)响应面法(RSM),优化了萃取工艺,得到了最佳操作条件:温度50oC,压力8.4 MPa,CO摩尔分数0.22及乙醇流速5 m L/min。CXE萃取的油得率为5.12-7.42%,显著高于常规方法。气相色谱-质谱(GC-MS)分析了CXE方法得到的香根草精油样品。结果表明,CXE油主要成分为烃、醇、羰基化合物及羧酸,其中22种成分与传统香根草精油的成分相同或相似。CXE油中的三种主要成分分别为valerenol(18.48%)、valerenal(10.21%)和β-cadinene(6.23%)。(3)结合GC-MS分析,对香根草油进行了两阶段的分子蒸馏,进一步精制分离。通过调节压力、进料温度、蒸发温度、进料速度和刮板转速进行第一阶段分子蒸馏,在低压(0-2 Pa)、进料温度80oC的条件下,可以确保精油样品的流动性,其密度约为0.878g/m L,粘度为4.764 mPa·s。在蒸发温度80oC的条件下可得到相对较高的总回收率(79.81%),并得到三个馏分:1R含量为28.61%,1D为51.01%和1D为0.19%。刮板转速设定为300 rpm,进料速度为2 m L/min,可形成约5 mm完整的蒸发膜,停留时间约为15 s。第二阶段的分子蒸馏将一级冷凝器温度降为5oC,其他条件与第一阶段相同。GC-MS分析表明,在第一阶段分子蒸馏中,可以去除大部分相对分子量较高的非挥发组分,在第二次分子蒸馏中,轻馏分(2D)中,一些特定组分出现了富集,如khusimene(1.79%),β–vatirenene(5.86%)和humulane-1,6-dien-3ol(10.74%)等。此外,两阶段的分子蒸馏总共发现了74种成分,第一阶段发现了38种成分,第二阶段发现了43种成分。经分子蒸馏后,GC色谱峰的分离度显著改善,因而分子蒸馏可用作色谱法鉴定香精油总组成的预处理方法。(4)通过DPPH和ABTS自由基清除试验检测了传统提取和绿色提取的香根草精油的抗氧化活性,结果表明香根草精油的抗氧化能力按降序排列依次为:IVD>HD>CXE>SFE。此外,DPPH自由基清除试验表明,新方法得到的香根草精油及分子蒸馏馏分的抗氧化活性与传统精油相近。(5)通过微量稀释法测定了香根草精油对革

关键词：香根草油 CO2膨胀乙醇分子蒸馏 GC-MS 生物活性

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The ARTICONF approach to decentralized car-sharing

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Blockchain(Research and Applications) 2021年第3期2卷 1-16页

作者： Nishant Saurabh Carlos Rubia Anandakumar Palanisamy Spiros Koulouzis Mirsat Sefidanoski Antorweep Chakravorty Zhiming Zhao Aleksandar Karadimce radu Prodan Institute of Information Technology University of KlagenfurtK€arnten 9020Austria Agilia Center Aljaraque21110Spain bitYoga AS Stavanger4021Norway Institute for Informatics University of AmsterdamAmsterdam1012 WXNetherlands University of Information Science and Technology Ohrid North Macedonia University of Stavanger stavanger4021Norway

Social media applications are essential for next-generation ***,social media are centralized platforms with a single proprietary organization controlling the network and posing critical trust and governance issues over the created and propagated *** ARTICONF project funded by the European Union's Horizon 2020 program researches a decentralized social media platform based on a novel set of trustworthy,resilient and globally sustainable tools that address privacy,robustness and autonomy-related promises that proprietary social media platforms have failed to deliver so *** paper presents the ARTICONF approach to a car-sharing decentralized application(DApp)use case,as a new collaborative peer-to-peer model providing an alternative solution to private car *** describe a prototype implementation of the car-sharing social media DApp and illustrate through real snapshots how the different ARTICONF tools support it in a simulated scenario.

关键词： Social media Car-sharing Decentralization Blockchain

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Blockchain-based prosumer incentivization for peak mitigation through temporal aggregation and contextual clustering

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Blockchain(Research and Applications) 2021年第2期2卷 82-96页

作者： Nikita Karandikar Rockey Abhishek Nishant Saurabh Zhiming Zhao Alexander Lercher Ninoslav Marina radu Prodan Chunming Rong Antorweep Chakravorty Department of Electrical Engineering and Computer Science University of StavangerStavanger86004036Norway Department of Energy and Petroleum Engineering University of StavangerStavanger86004036Norway Institute of Information Technology University of KlagenfurtKlagenfurt am Worthersee9020Austria Multiscale Networked Systems University of AmsterdamAmsterdam 1012 WXNetherlands University of Information Science and Technology OhridNorth Macedonia

Peak mitigation is of interest to power companies as peak periods may require the operator to over provision supply in order to meet the peak *** the usage curve can result in cost savings,both for the power companies and the end *** of renewable energy into the energy infrastructure presents an opportunity to use excess renewable generation to supplement supply and alleviate *** addition,demand side management can shift the usage from peak to off-peak times and reduce the magnitude of *** this work,we present a data driven approach for incentive-based peak *** user energy profiles is an essential step in this *** begin by analysing a popular energy research dataset published by the Ausgrid *** aggregated user energy behavior in temporal contexts and semantic linking and contextual clustering give us insight into consumption and rooftop solar generation *** implement,and performance test a blockchain-based prosumer incentivization *** smart contract logic is based on our analysis of the Ausgrid *** implementation is capable of supporting 792,540 customers with a reasonably low infrastructure footprint.

关键词： Peak shaving Aggregation analysis Contextual clustering Blockchain Incentivization

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Clinical characteristics and outcomes in carbohydrate antigen 19-9 negative pancreatic cancer

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World Journal of Clinical Oncology 2022年第7期13卷 630-640页

作者： Daniel Vasile Balaban Flavius Stefan Marin George Manucu andreea Zoican Marina Ciochina Victor Mina Cristina Patoni Catalina Vladut Sandica Bucurica Raluca Simona Costache Florentina Ionita-radu Mariana Jinga Department of Gastroenterology Carol Davila University of Medicine and PharmacyDr.Carol Davila Central Military Emergency University HospitalBucharest 020021Romania Department of Gastroenterology and Digestive Oncology Hôpital CochinParis 75014France Department of Gastroenterology Carol Davila University of Medicine and PharmacyProf Dr.Agrippa Ionescu Clinical Emergency HospitalBucharest 020021Romania

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is a leading cause of death from cancer *** markers like carbohydrate antigen 19-9(CA 19-9)have been proven valuable as a diagnostic tool and a predictor for tumor staging and response to *** To delineate the phenotype of normal CA 19-9 PDAC according to clinical features,disease staging and prognosis as compared with high CA 19-9 PDAC *** We performed a retrospective single-center analysis of all PDAC cases admitted in our Gastroenterology department over a period of 30 mo that were diagnosed by endoscopic ultrasound-guided tissue *** were divided into two groups according to CA 19-9 levels over a threshold of 37 U/*** performed a comparison between the two groups with regard to demographic and clinical data,biomarkers,tumor staging and 6-mo *** Altogether 111 patients were recruited with 29 having documented normal CA 19-9(<37 U/mL).In the CA 19-9 negative group of patients,20.68%had elevated levels of both CEA and CA 125,13.79%for CA 125 only whilst 17.24%for CEA *** two groups had similar demographic *** pain was more frequently reported in positive vs negative CA 19-9 PDAC cases(76.83%vs 55.17%),while smoking was slightly more prevalent in the latter group(28.04%vs 31.03%).Tumors over 2 cm were more frequently seen in the positive CA 19-9 group,reflecting a higher proportion of locally advanced and metastatic neoplasia(87.7%vs 79.3%).Sixmonth survival was higher for the negative CA 19-9 group(58.62%vs 47.56%).CONCLUSION Elevated CA 19-9 at diagnosis seems to be associated with a more pronounced symptomatology,high tumor burden and poor prognosis compared to negative CA 19-9 PDAC *** and CA 125 can be adjunctive useful markers for PDAC,especially in CA 19-9 negative cases.

关键词： Pancreatic cancer Carbohydrate antigen 19-9 Survival Lewis Outcome

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Solid state anaerobic digestion of water poor feedstock for methane yield:an overview of process characteristics and challenges

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Waste Disposal and Sustainable Energy 2021年第3期3卷 227-245页

作者： Kunwar Paritosh Vinod Kumar Nidhi Pareek Dinabandhu Sahoo Yadira Bajon Fernandez Frederic Coulon Tanja radu Nupur Kesharwani Vivekanand Vivekanand Centre for Energy and Environment Malaviya National Institute of TechnologyJaipurRajasthan 302017India School of Water Energy and EnvironmentCranfield UniversityCranfield MK430 ALUK Department of Microbiology School of Life SciencesCentral University of Rajasthan BandarsindriKishangarhAjmerRajasthan 305801India Department of Botany University of DelhiDelhi 110007India School of Architecture Building and Civil EngineeringLoughborough UniversityLoughborough LE113TUUK Department of Civil Engineering National Institute of TechnologyRaipurChhattisgarh 492010India

Solid state anaerobic digestion(SSAD)of water poor feedstock may be a promising technology for energy *** having high solid concentration like lignocellulosic biomass,crop residues,forestry waste and organic fraction of municipal waste may be the appropriate feedstock for its biochemical conversion into energy carries like biomethane through *** to liquid state anaerobic digestion(LSAD),SSAD can handle higher organic loading rates(OLR),requires less water and smaller reactor volume and may have lower energy demand for heating or stirring and higher volumetric methane *** these,pathogen inactivation may also be achieved in SSAD of biodegradable *** 60%of recently built AD systems have adopted SSAD ***,the process stability of an SSAD system may have several constraints like limited mass transfer,process inhibitors and selection of digester type and should be addressed prior to the implementation of SSAD *** this article,a comprehensive overview of the key aspects influencing the performance of SSAD is discussed along with the need for mathematical modelling *** to this,reactor configuration for SSAD and digestate management requirement and practice for solid-state condition are reviewed for a better insight of SSAD technology.

关键词： Solid state anaerobic digestion Clean energy Mathematical modelling Digestate management Biogas Biomass

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The Modeling of the Heating Resistors in Transient Regime

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材料科学与工程（中英文B版） 2011年第2期1卷 170-177页

作者： Mitica Iustinian Neaca andreea Maria Neaca Faculty of Electrotechnics University of Craiova Bdul Decebal nr. 107 Craiova 200440 Romania

The present paper presents an applicative solution of mathematical modeling and simulation for resistive heating elements. A frequently problem, which appears during the use of these ovens, is the rapid aging who leads to the break down the heating resistors. This model allows the simulation of the transient self-heating regime, as well as of the continuous heating regime. To verify this, the authors have realized a more complex model of an electrical oven with resistors, which integrates the models of the heating resistors as subsystems. The paper presents a part of the simulation results and the conclusions generated by their analysis.

关键词：加热元件数学建模电阻器瞬态加热制度加热电阻微波炉老龄化

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罗马尼亚语版《当代中文》研究

罗马尼亚语版《当代中文》研究

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作者： Marcu andreea 浙江大学

学位级别：硕士

随着中国经济的发展,中国在世界上的地位越来越重要了,所以学习汉语的外国人越来越多。由于罗马尼亚和中国的关系越来越亲密,越来越多的罗马尼亚人开始学习汉语。目前在罗马尼亚有几种汉语教材,《当代中文》的罗马尼亚语版在大学应用较... 详细信息

随着中国经济的发展,中国在世界上的地位越来越重要了,所以学习汉语的外国人越来越多。由于罗马尼亚和中国的关系越来越亲密,越来越多的罗马尼亚人开始学习汉语。目前在罗马尼亚有几种汉语教材,《当代中文》的罗马尼亚语版在大学应用较多,而且是在大学目前唯一一部罗语教材。本文主要以罗马尼亚语版(2010年修订版)汉语教材《当代中文(初级)》(吴中伟编著,由李家渔,骆东泉翻译)为分析对象,研究该教材存在的翻译问题以及其他与教材适用性方面相关的问题,例如罗马尼亚母学习者使用该教材时遇到的实际问题和使用效果。本文主要通过内容分析法和问卷调查的方法,分析罗马尼亚语版《当代中文》存在的翻译问题,以及罗马尼亚汉语学者对教材的使用体验和对《当代中文》的评价。研究发现,罗马尼亚语版《当代中文》在翻译上有很明显的问题,包括词汇与句子的准确性、翻译的含义和对照、译文语义的自然性和流畅性以及翻译中的语法错误等等,。此外对使用者的调查研究结果也为《当代中文》教材提出了一些不足及改进意见。这些研究结果对完善罗马尼亚本地汉语教材有直接的启示作用。

关键词：当代中文罗马尼亚翻译本土化

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关于最佳风场和风轮尺寸的研究

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太阳能学报 1993年第1期14卷 77-84页

作者： Gheorghe Olaru Adriau radu 罗马尼亚电工研究所布加勒斯特

为了降低风力发电成本,使其具有较好的经济性,应选择最佳的风场和与之匹配的风力机。以安装在罗马尼亚加拉茨(Galati)和苏利纳(Sulina)的10kW和1000kW风力发电机为例进行了分析讨论。

关键词：风力发电风电场风力发动机风轮

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罗马尼亚在建立路面管理系统与HDM—Ⅲ联系方面的经验

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公路交通科技 1996年第A期13卷 134-136页

作者： radu,PE 张建

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Allergic rhinitis facts from an Irish pediatric population

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2023年第4期9卷 333-339页

作者： andreea Nae Colleen B.Heffernan Michael Colreavy Department of Otorhinolaryngology Ireland

Objective:Assessing the main allergens in the pediatric population from the largest urban area in the ***:Clinical letters of patients referred with possible allergic rhinitis(AR)were retrospectively reviewed over the past 5 ***:Five hundred and fifty‐five patients were *** suffer twice as often with AR than females and have high titers of *** dust mites(44.7%)and grass pollen(29%)were the main allergens in our area,with 48%of patients sensitized to both *** of the patients had the diagnosis of AR confirmed with positive allergen‐specific *** the other half,the diagnosis was based on a clinical assessment performed by a pediatric ***:Half of suspected AR children have environmental allergen sensitivity confirmed by testing,and a large number had a clinical diagnosis of AR after an otolaryngology *** findings can help clinicians to initiate AR treatment considering the most problematic allergens in the area.

关键词： aeroallergens allergic rhinitis grass pollens house dust mites skin prick

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