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Detoxification of ferrocyanide in a soil–plant system

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Journal of Environmental Sciences 2019年第3期31卷 54-64页

作者： Tsvetelina dimitrova Frank Repmann Dirk Freese Brandenburg University of Technology Cottbus-Senftenberg

The detoxification of iron cyanide in a soil–plant system was investigated to assess the total cyanide extracted from contaminated soil and allocated in the leaf tissue of willow trees(Salix caprea). They were grown in soil containing up to 1000 mg/kg dry weight(dw) of cyanide(CN),added as ^(15)N-labeled potassium ferrocyanide and prepared with a new method for synthesis of labeled iron cyanides. CN content and ^(15)N enrichment were monitored weekly over the exposure in leaf tissue of different age. The ^(15)N enrichment in the young and old leaf tissue reached up to 15.197‰ and 9063‰, respectively; it increased significantly over the exposure and with increasing exposure concentrations(p < 0.05). Although the CN accumulation in the old leaf tissue was higher, compared to the young leaf tissue(p < 0.05), the ^(15)N enrichment in the two tissue types did not differ statistically. This indicates a non-uniform CN accumulation but a uniform ^(15)N allocation throughout the leaf mass. Significant differences were detected between the measured CN content and the C^(15)N content, calculated from the ^(15)N enrichment(p < 0.05), revealing a significant CN fraction within the leaf tissue, which could not be detected as ionic CN. The application of labeled iron CN clearly shows that CN is detoxified during uptake by the willows. However, these results do not exclude other detoxification pathways, not related to the trees. Still, they are strongly indicative of the central role the trees played in CN removal and detoxification under the experimental conditions.

关键词： Iron cyanide Detoxification Exposure Phytoremediation

Improved proper motion determinations for 15 open clusters based on the UCAC4 catalog

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Research in Astronomy and Astrophysics 2016年第7期16卷 39-46页

作者： Alexander Kurtenkov Nadezhda dimitrova Alexander Atanasov Teodor D.Aleksiev Department of Astronomy University of Sofia5 James Bourchier Blvd.1164 SofiaBulgaria Institute of Astronomy and National Astronomical Observatory Bulgarian Academy of Sciences72 Tsarigradsko Shose Blvd.1784 SofiaBulgaria Anglo-American School of Sofia 1 Siyanie Str.1138 SofiaBulgaria Geo Milev High School of Mathematics Storgozia5802 PlevenBulgaria Sofia High School of Mathematics 61 Iskar Str.1000 SofiaBulgaria

The proper motions of 15 nearby（d 〈 1 kpc） open clusters（OCs） were recalculated using data from the UCAC4 catalog. Only evolved or main sequence stars inside a certain radius from the center of the cluster were used. The results significantly differ from the ones presented by Dias et al.（2014）. This could be explained by a different approach in which we take the field star contamination into account. The present work aims to emphasize the importance of applying photometric criteria for the calculation of OC proper motions.

关键词： proper motions Galaxy open clusters and associations general

China’s Energy Silk Road to the Caspian Region and Its Geopolitical Implications

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China’s Energy Silk Road to the Caspian Region and Its Geop...

作者： Julita Pacewicz-dimitrova 外交学院

学位级别：硕士

As China diversifies its energy strategy towards the historic Silk Road, many wonderabout the geopolitical implications of this move. This paper analyses motives behind country’s expansion in the Caspian region, focusingon energy security as an integrating factor of a complex strategy. It proves that the resourcerich area is also of great political, security and economic importance to Beijing. China’s well-timed energy quest combined with economic influence and financialinvolvement in the Caspian states, help to establish win-win cooperation. Non-interventionprinciple and relative neutrality of Beijing’s foreign policy, as well as similar view onregional security issues, allow establishing integration mechanisms and bolstering China’sgeopolitical influence in the region. The research includes perspective on major powers competition in Central Asia in contextof Chinese accomplishments. As Russia, the US, EU, India and Iran struggle forsupremacy in this focal point of global geopolitics, Beijing’s dominance seems hard totopple. Findings prove that China has been effectively implementing its geopolitical strategyobjectives in the Caspian and became successful player in regional energy game.

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The Analysis on the Trade Relations of Sino-Bulgaria

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The Analysis on the Trade Relations of Sino-Bulgaria

作者： Maria dimitrova Ignatova 华中师范大学

学位级别：硕士

保加利亚是东南欧的一个小国,位于罗马尼亚和土耳其之间的黑海海岸354公里处,与前南斯拉夫和希腊接壤。其次还与阿塞多尼亚、罗马尼亚、塞尔维亚和土耳其相邻。保加利亚有700多万的人口,首都在索非亚。本研究的目的是探讨1949年以来保... 详细信息

保加利亚是东南欧的一个小国,位于罗马尼亚和土耳其之间的黑海海岸354公里处,与前南斯拉夫和希腊接壤。其次还与阿塞多尼亚、罗马尼亚、塞尔维亚和土耳其相邻。保加利亚有700多万的人口,首都在索非亚。本研究的目的是探讨1949年以来保加利亚与中国贸易关系的现状和动态。保加利亚和中国的贸易和经济关系有着悠久的历史,两国元首高度重视双边经贸合作的重要性,并给予了有力的支持。在庆祝保加利亚与中华人民共和国建交65周年之际,两国建立了全面的友好合作伙伴关系,并努力将两国的合作提高到一个新的、更高的水平,因此,提高双方在所有领域的合作水平成为了两国未来的主要目标。保加利亚和中国的双边关系近年来迎来了新的阶段,双方在多方面开展合作,两国关系稳步发展,政治互信不断加深,经济、贸易、投资、农业、文化、教育等方面的发展成效有目共睹。保加利亚和中国承诺在平衡的基础上努力扩大贸易,为此,两国将努力提供必要的体制基础,寻求农业合作的新形式,这有可能成为两国务实合作的一个新的重要方向。保中双方将积极发挥各自的优势,扩大与高速公路、隧道、桥梁建设有关的合作伙伴关系。并促进保加利亚的机场扩建、港口、铁路和其他基础设施和能源项目的现代化。保加利亚和中国公司之间也正在寻求在能源、新技术、创新、可再生能源等领域的合作共同发展。在中国政府看来,保加利亚是进一步投资的重要战略国家之一,为此需要筹建两国的商业论坛,其目的是建立一个平台,在两国公司之间建立一个信息交流机制。这样的信息交流机制将取得令人满意的结果,无疑将对今后贸易的扩大和两国之间的经济关系产生积极的影响。本研究旨在为中国政府或企业在保加利亚的贸易机会提供一个理论分析的框架。通过对经济发展环境和保加利亚现有中国投资者经验的综述,可以帮助中国政府或公司充分了解保加利亚的经济状况。事实上,无论是学术工作者还是其他行业从业者,都为进一步研究中国与保加利亚的贸易关系将提供至关重要的信息。从理论上讲,通过中国对保加利亚贸易影响的概况描述和中国企业在保加利亚市场上的经验研究,将有助于促进保加利亚贸易的发展。此外,本研究旨在为寻求在保加利亚市场拓展业务的中国企业或政府提供一些启示和政策建议。这项研究的结果将有助于我们协助策划他们的贸易策略,并计划未来的发展方向。本研究将重点放在中国与保加利亚之间的贸易关系上,将有助于更好地发展两国贸易市场。这也为政府官员提供了一个清晰的路径,使他们能够采取重大行动,发展国际合作。中国与保加利亚于1949年10月4日建交,1952年中保签订了两国政府间第一个贸易协定,实行政府间记账贸易方式。从1991年开始改为现汇贸易方式。2017年中国自保加利亚进口额为9.69亿美元,中国向保加利亚的出口额为11.69亿美元。同年,保加利亚的总进口为342.64亿美元,总出口额为315.88亿美元。作为欧盟的成员国之一,其超过一半的货物贸易是在欧盟内部进行,也就是说保加利亚与中国的贸易关系目前一直处于非常低的水平。虽然中国和保加利亚的贸易额比较低,但是随着中国“一带一路”战略的推进和中欧“16+1合作”的开展,中保贸易关系迎来了较好的发展机遇,在这样的背景下分析中保贸易关系中存在的问题就显得尤为重要。本文的研究将对今后的研究产生重要的意义。本文先描述中国与保加利亚贸易关系的历史和现状,探讨中国与保加利亚政府在国际贸易合作中面临的问题和困难,最后提出建设性的意见。本研究主要探讨和解决的一些问题是:1.分析中保贸易关系中存在的问题?中国和保加利亚的贸易异质处于比较低的水平,虽然在中国“一带一路”战略和中欧“16+1合作”的推进,但是中保贸易还存在这一些结构性的问题,分析这些问题对于理解中保贸易的特点和未来趋势有着重要的意义。首先,两国经贸往来还不够多,对对方市场情况了解不够透彻,合作机会还不多;其次,在大多数情况下,中国和保加利亚企业作为“独行侠”在国外开拓市场,没有实现规模效益,没有有针对性的战略规划,资源还没有得到充分的汇集和利用;第三,监管措施和政策不够稳定。2.怎样改善中国和保加利亚的贸易合作以及未来合作前景?在分析问题的基础上,探讨这些问题产生的原因,并研究如何改善中国和保加利亚的贸易合作,并对中国和保加利亚的贸易合作的前景进行展望。中保经贸合作是建立在两国要素禀赋优势基础上的,双边合作的扩大和深化有利于促进保加利亚经济的发展。保加利亚越来越倾向于向中国出口货物,出口值近年来稳步上升。表明保中两国贸易关系发生了明显变化。两国应努力提供必要的体制基础,并寻求新的农业合作形式。保中双方应当积极发挥各自的优势,扩大在保高速公路、隧道、桥梁、机场扩建、港口、铁路等基础设施和能源项目建设方面的伙伴关系。3.中国作为保加利亚的贸易伙伴和来源地国对保加利亚的重要意义是什么?虽然保加利亚的主要贸易伙伴国都在欧盟内部,但

关键词： Sino-Bulgarian trade relations One Belt One Road 16+1 Cooporation

Prognostic value of von-Willebrand factor in patients with liver cirrhosis and its relation to other prognostic indicators

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World Journal of Hepatology 2022年第4期14卷 812-826页

作者： Elena Curakova Ristovska Magdalena Genadieva-dimitrova Intensive Care Unit University Clinic for GastroenterohepatologySkopje 1000North Macedonia Faculty of Medicine Ss.Cyril and Methodius University in SkopjeSkopje 1000North Macedonia Hepatology Department University Clinic for GastroenterohepatologySkopje 1000North Macedonia

BACKGROUND Von-Willebrand factor(vWF)disposes certain prognostic value in patients with liver cirrhosis,but its relation to other prognostic indicators has not been fully *** To analyze the relation between vWF and other prognostic indicators in cirrhotic patients and to evaluate its prognostic value for *** This analytic prospective study was carried out in a tertiary center and initially enrolled 71 patients with liver cirrhosis and portal *** analyzed the relation between vWF and the stage of the disease and several inflammatory and prognostic *** prospective analysis,performed on a sample of 63 patients,evaluated the association between the selected variables[vWF,Model for End-stage Liver Disease(MELD)score,C-reactive protein(CRP),ferritin,vitamin D,activated partial thromboplastin time,thrombin time,D-dimer concentration]and the survival time as well as their predictive value in terms of 3-mo,6-mo and 1-year *** vWF was significantly higher in patients with higher Child-Turcotte-Pugh class(P=0.0045),MELD group(P=0.0057),ferritin group(P=0.0278),and D-dimer concentration(P=0.0232).vWF significantly correlated with D-dimer concentration,ferritin,CRP,International Normalized Ratio,and MELD,Child-Turcotte-Pugh,Sequential Organ Failure Assessment,and CLIF-consortium organ failure(CLIF-C OF)***,MELD score,and CRP were significantly associated with death and were significant predictors of 3-mo,6-mo,and 1-year *** vWF unit significantly increased the probability for 3-mo mortality by 1.005 times(P=0.008),for 6-mo mortality by 1.006 times(P=0.005),and for 1-year mortality by 1.007 times(P=0.002).There was no significant difference between the diagnostic performance of vWF and MELD score and also between vWF and CRP regarding the 3-mo,6-mo,and 1-year *** In patients with liver cirrhosis,vWF is significantly related to other prognostic indicators and is a significant predict

关键词： von-Willebrand factor Cirrhosis Mortality C-reactive protein D-dimer

Corona-Support for the Entirety of High Energetic Disk

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Journal of Earth Science and Engineering 2012年第7期2卷 395-400页

作者： Krasimira dimitrova Yankova Space and Solar-Terrestrial Research Institute Bulgarian Academy of Sciences Sofia i113 Bulgaria

Based on results obtained from the study for MHD （magneto-hydrodynamics） of advective accretion disk, which are applied to real source showing typical values for CBS （close binary star-system）, it will investigate on self-structuring in the disk under the impact of the distribution of leading parameters （density, velocity ...）. The paper is considering the problem of development of the corona and will analyze the process of interaction of the plasma with the magnetic field in connection to support for the instabilities.

关键词： Accretion disk advection MHD (magneto-hydrodynamics) instabilities.

Official Statistics as Clickbait—The New Threat in the Post-truth Society?

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Journal of Mathematics and System Science 2019年第4期9卷 95-99页

作者： Lyubomira dimitrova Department of Public Administration Sofia Univeristy“St.Kliment Ohridski”125 Tsarigradsko shose blvdbl.44131113 SofiaBulgaria

The aim of this paper is to raise awareness on the consequences of dissemination of official statistics through online media that uses clickbait headlines to generate *** order to tackle on this issue,a Natural Language Processing(NLP)model was developed in order to distinguish the clickbait headline from the non-clickbait one when it comes to articles presenting information from the Bulgarian National Statistical Institute press *** yielded results are rather satisfactory as the parts-of-speech features model achieved an accuracy for 92%of the cases.

关键词： Official statistics online media clickbait

Steganography of Hypertext Transfer Protocol Version 2 (HTTP/2)

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Journal of Computer and Communications 2017年第5期5卷 98-111页

作者： Biljana dimitrova Aleksandra Mileva Faculty of Computer Science University Goce Delcev &Scaron tip Republic of Macedonia

Network steganography consists of different steganographic technics that utilize network protocols for hiding data. We present nine new covert channels which utilize the new standard, HTTP/2, and which can be used regardless its transport carrier (TLS or clear TCP). These covert channels use a protocol feature that has dual nature (for example, no padding can be represented in two ways);or a feature that is not mandatory (as streams prioritization and dependencies);or random value field (as PING frame payload field);or there is no strict rule how to obtain new values for some fields (as stream identifiers). As far as we know, this is the first research about hiding data in HTTP/2. Also, we give a small survey of existing covert channels that can be created using HTTP/1.x, with the analysis do they work or not work with the HTTP/2.

关键词： Network Steganography Network Security Information Hiding Covert Channels

Simulation Models for Evaluation and Selection of Depreciation Policy for Agricultural Companies in the Republic of Bulgaria

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Journal of Modern Accounting and Auditing 2013年第10期9卷 1322-1333页

作者： Ivanka Borisova dimitrova Yordanka Velcheva "Angel Kanchev" University of Ruse Ruse Republic of Bulgaria

In the present paper, the results from research on the influence of criteria （factors） such as depreciation method, materiality threshold, and inflation rate on the selection of depreciation policy are shown. The research has been carried out with the help of specifically devised simulation models. The simulation is realized in accounting for the unevenness of money in time and the profitability of the company, the tax rates for corporate tax, and the inflation rate. The models have been devised after analyzing methodology issues, related to depreciation policy and investigating current practices in its implementation in specific agricultural companies in present-day Bulgaria. It has been determined that there is a clear-cut relation between the profitability of the companies and the materiality threshold and depreciation method chosen. The main conclusion is that when the companies develop their depreciation policy, at ceteris paribus they should select higher materiality thresholds and diminishing balance depreciation methods due to the inequality of money in time, the acceleration of obsolescence, and the inflation processes.

关键词： depreciation policy materiality threshold methods of depreciation future value inflation rate