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ANALYSIS OF REGULATION AND HARMONIZATION IMPLIED IN A-B CLASSIC ON ACUPUNCTURE AND MOXIBUSTION
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作者 姜燕 马新平 《World Journal of Acupuncture-Moxibustion》 2007年第1期46-48,共3页
It aims to draw the conclusion that the ideas of treatment in Zhen Jiu Jia Yi Jing (《针灸甲乙经》, A-B Classic on Acupuncture and Moxibustion ) can be summarized as "regulation" and "harmonization" through the ... It aims to draw the conclusion that the ideas of treatment in Zhen Jiu Jia Yi Jing (《针灸甲乙经》, A-B Classic on Acupuncture and Moxibustion ) can be summarized as "regulation" and "harmonization" through the research of words in the Classic, such as "being normal", "regulation" and "harmonization". The lost of regulation of a normal person shows disharmony. Regulation can make the person-being-sick become harmony and back to "being normal". "Regulation" and "harmonization" right imply the quintessence of traditional Chinese medicine. 展开更多
关键词 A-B Classic on Acupuncture and Moxibustion Rgulation and harmonization Being normal
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Unification and Harmonization in True Color Image City Map 被引量:3
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作者 ZHAO Xi PANG Xiaoping +1 位作者 ZHANG Shengli ZHANG Xiang 《Geo-Spatial Information Science》 2007年第1期75-78,共4页
True color image city map is a sort of new-style map which combines the high resolution image and map symbols and shows both advantages in visualization. At the same time, the map unification and harmonization should ... True color image city map is a sort of new-style map which combines the high resolution image and map symbols and shows both advantages in visualization. At the same time, the map unification and harmonization should be taken into account dur-ing the design process, since some visual conflicts appear when map symbols overlaid on the true color image. The objective of this research is to explore the rules in the process of true color image city map design based on chromatic and aesthetic knowledge. At the end, taking the Image Atlas of Guangzhou as an example, image color adjustment, road network presentation, and symbol de-signing issues will be discussed in the application. 展开更多
关键词 true color image city map map design unification harmonization
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The promotion of international certification harmonization of welding fabrication industries
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作者 解应龙 陈宇 +1 位作者 钱强 戴万福 《China Welding》 EI CAS 2005年第1期6-8,共3页
Enterprises and their products require corresponding international qualification when they participate in international market competition after China joined WTO. At present, the number of certified welding fabricatio... Enterprises and their products require corresponding international qualification when they participate in international market competition after China joined WTO. At present, the number of certified welding fabrication companies is still small. However, more and more enterprises are getting to realize the importance, and we have already had the following basic conditions: welding personnel qualification according to the international guidelines and rules, welding standards equivalent to ISO and EN standards, as well as full successful experiences of company certification gained through cooperation between China and Germany. So with additional industries’ support and government’s attention, company certification according to international rules will provide qualification guarantee for welding fabrication companies to participate in international market competition. 展开更多
关键词 COMPANY CERTIFICATION international harmonization
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Harmonization of Political and Administrative Boundaries in Kenya Using GIS: A Case Study of Mavoko Constituency
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作者 Kyatu Irene Godfrey Makokha Moses Ngigi 《Journal of Geographic Information System》 2017年第2期141-157,共17页
The objective of this research was to harmonize political and administrative boundaries in Mavoko Constituency, Machakos County, Kenya, using geo-spatial technology and public consultation in order to address the nume... The objective of this research was to harmonize political and administrative boundaries in Mavoko Constituency, Machakos County, Kenya, using geo-spatial technology and public consultation in order to address the numerous disputes that exist. Specifically, the project focused on analyzing the existing electoral and administrative boundaries in the area of study by identifying all existing gaps and overlaps, rectifying the identified gaps and overlaps and created a web based geo-portal of the harmonized sub location boundaries to enable sharing. This was achieved through first putting the various datasets on the same Spatial Reference System and comparing them in order to identify and rectify them using various geospatial operations, public consultation and field work. The result was a single harmonized layer for the sub location data set for the study area. The project finally developed a customized GIS web based portal for sharing the harmonized Sub location boundary. This was uploaded on an open source platform, which has the capability for offline use in the field. The project worked on a hypothesis that if the sub location boundaries adopted by the various Government and Public organizations and individuals doing any kind of mapping in Kenya was a single harmonized data set, the emerging issues on boundary disputes between Counties, Constituencies and County Assembly Wards (CAW’s) would not occur. This is because there would be authentic, consisted and authoritative geo-information which maintains a harmonized, consistent, reusable and readily available data. The development of the geo portal ensured that the results of the research are easily accessible on www.msc2015boundariesmavoko.info.ke/mavoko. 展开更多
关键词 Boundaries Data SHARING Geo PORTAL GIS harmonization
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Modulation of High-Order Harmonic Generation from a Monolayer ZnO by Co-rotating Two-Color Circularly Polarized Laser Fields 被引量:1
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作者 乔月 陈家祺 +3 位作者 周书山 陈基根 蒋士成 杨玉军 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第1期34-38,共5页
By numerically solving the two-dimensional semiconductor Bloch equation,we study the high-order harmonic emission of a monolayer ZnO under the driving of co-rotating two-color circularly polarized laser pulses.By chan... By numerically solving the two-dimensional semiconductor Bloch equation,we study the high-order harmonic emission of a monolayer ZnO under the driving of co-rotating two-color circularly polarized laser pulses.By changing the relative phase between the fundamental frequency field and the second one,it is found that the harmonic intensity in the platform region can be significantly modulated.In the higher order,the harmonic intensity can be increased by about one order of magnitude.Through time-frequency analysis,it is demonstrated that the emission trajectory of monolayer ZnO can be controlled by the relative phase,and the harmonic enhancement is caused by the second quantum trajectory with the higher emission probability.In addition,near-circularly polarized harmonics can be generated in the co-rotating two-color circularly polarized fields.With the change of the relative phase,the harmonics in the platform region can be altered from left-handed near-circularly polarization to right-handed one.Our results can obtain high-intensity harmonic radiation with an adjustable ellipticity,which provides an opportunity for syntheses of circularly polarized attosecond pulses. 展开更多
关键词 POLARIZATION ROTATING harmonIC
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Wave Harmonization in Hierarchic Quasicrystals by the Analytic Metric
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2019年第11期1364-1373,共10页
Thirty seven years after the discovery of quasicrystals, their diffraction is completely described by harmonization between the sine wave probe with hierarchic translational symmetry in a structure that is often calle... Thirty seven years after the discovery of quasicrystals, their diffraction is completely described by harmonization between the sine wave probe with hierarchic translational symmetry in a structure that is often called quasiperiodic. The diffraction occurs in geometric series that is a special case of the Fibonacci sequence. Its members are irrational. When substitution is made for the golden section τ by the semi-integral value 1.5, a coherent set of rational numbers maps the sequence. Then the square of corresponding ratios is a metric that harmonizes the sine wave probe with the hierarchic structure, and the quasi-Bragg angle adjusts accordingly. From this fact follows a consistent description of structure, diffraction and measurement. 展开更多
关键词 QUASICRYSTAL ICOSAHEDRA Hierarchic harmonization METRIC Geometric Series
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ESTIMATE ON THE BLOCH CONSTANT FOR CERTAIN HARMONIC MAPPINGS UNDER A DIFFERENTIAL OPERATOR 被引量:1
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作者 陈洁玲 刘名生 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期295-310,共16页
In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,... In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,using these results,we present better estimations for the Bloch constants of certain harmonic mappings L(f),where f is a K-quasiregular harmonic or open harmonic.Finally,we establish three versions of BlochLandau type theorem for biharmonic mappings of the form L(f).These results are sharp in some given cases and improve the related results of earlier authors. 展开更多
关键词 Bloch-Landau type theorem Bloch constant linear complex operator harmonic mapping biharmonic mapping UNIVALENT
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A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data 被引量:2
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作者 Yunping Chen Jie Hu +6 位作者 Zhiwen Cai Jingya Yang Wei Zhou Qiong Hu Cong Wang Liangzhi You Baodong Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1164-1178,共15页
Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while r... Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural inputs.However,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy weather.In this study,taking Qichun County in Hubei Province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)images.The PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature selection.Based on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover types.Furthermore,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice map.Finally,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively.These results demonstrate that the proposed PRVI based on HLS data can effectively identify ratoon rice in fragmented croplands at crucial phenological stages,which is promising for identifying the earliest timing of ratoon rice planting and can provide a fundamental dataset for crop management activities. 展开更多
关键词 ratoon rice phenology-based ratoon rice vegetation index(PRVI) phenological phase feature selection harmonized Landsat Sentinel-2 data
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Harmonics in the Squirrel Cage Induction Motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic 被引量:1
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作者 G.Kovács 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期86-102,共17页
The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an... The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the engineer.Thus, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end. 展开更多
关键词 Asynchronous parasitic torques Induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques
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International Harmonization of Guidelines-Role of ICLAS
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作者 Gilles Demers M.Sc. 《中国实验动物学报》 CAS CSCD 2005年第S1期1-,共1页
关键词 International harmonization of Guidelines-Role of ICLAS WILL
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Harmonization in auditing profession
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作者 Diaconu Paul Coman Nicoleta Dobroteanu Camelia Liliana Dobroteanu Laurentiu Minu Mihaela 《Journal of Modern Accounting and Auditing》 2009年第5期30-41,共12页
The globalization process is affecting a lot the economical environment and in many spheres has characterized the last decade of the twentieth century; accounting and auditing as information tools of the real econom... The globalization process is affecting a lot the economical environment and in many spheres has characterized the last decade of the twentieth century; accounting and auditing as information tools of the real economy are no exception. This paper introduces the analysis of the ongoing process of harmonization of the qualification to audit at a global level. The aim of the paper is to throw light on the processes of harmonizing auditing and accounting on a global basis, an issue that is of considerable debate at the current time both in the accountancy profession and in academia. The paper is structured is several chapters. In the first chapter entitled "Process of globalization and accounting evolution" the authors are presenting the steps in the main harmonization process and its major players during the last decades. The engine of internationalization seems to be the Anglo-Saxon accounting systems where the globalization issue was always very important. In the second chapter "Literature review" the authors are presenting some articles linked with the subject of our paper. In the third chapter "Harmonization of the qualification to audit" the authors are presenting need of "global qualification" in accounting and audit profession. In the fourth chapter "The field of global accountancy education", the authors are presenting the history of the adopting by the international organizations sustainable global education curricula in the field of accounting and audition profession. There the authors are underlying the role of Intergovernmental Working Group of Experts on International Standards of Accounting and Reporting International, which is considered to develop a "model curriculum" for a global accountancy qualification. Also is presented the IFAC's Education Committee's results and also the ACCA program in educational field. The chapter "Forces which are ruling the regulation process" is presented the IASC/IASB and the European directives in harmonization process. On the chapter "Global accountancy education" the authors are presenting the threats of using the need of "international qualification in audit" by developed countries as a tool of exploitation, using it as "cultural capital" for sale to developing countries (See the ACCA mechanism). Also the authors are presenting the IFAC role on building up international accounting curricula, which can be implemented through its members all over the world. The conclusions are trying to emphasize the steps which the accounting education needs to be followed in Romania due to the international evolutions. 展开更多
关键词 AUDITING accountancy education harmonization
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Harmonization of financial reporting of small and medium-sized enterprises in the Czech Republic
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作者 Libuse Mullerova Marie Pasekova Eva Hyblova 《Journal of Modern Accounting and Auditing》 2010年第1期55-64,共10页
A current problem of the present-day accounting and financial reporting consists in aligning the accounting in small and medium enterprises. In July 2009 the International Financial Reporting Standard for small and me... A current problem of the present-day accounting and financial reporting consists in aligning the accounting in small and medium enterprises. In July 2009 the International Financial Reporting Standard for small and medium-sized enterprises was issued, which extended the aligning possibilities also to small and medium enterprises considerably. If the standard is adopted by the national legislation, problems connected with the standard implementation in the national legislation will have to be solved as well as practical issues connected with making financial statements. At present the yields and the problems which can arise in connection with the standard application have to be focused on. A contribution of the standard application will be a better informative ability of financial statements on the international level. At small and medium enterprises this can contribute to better comanunication with banks, with investors, rating application are: parallel reporting according to national agencies etc. The problems connected with the standard regulations, differences between the national legislation and the standard, wide practice at keeping accounts and making financial statements and limited approach of small and medium enterprises to obtaining information and to training of their employees. Another problem can be a tight link between the trading income and the tax base, when small companies prefer rather the tax point of view. 展开更多
关键词 financial statements REPORTING small and medium-sized enterprises harmonization IFRS
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Principles of Indirect Tax Harmonization in the EU
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作者 Jaroslav Korecko Alzbeta Suhanyiova Ladislav Suhanyi 《Economics World》 2017年第6期608-617,共10页
Since the beginning of 60s of the 20th century the European Community has been voicing its concerns about the need for tax harmonization. First attitudes towards tax harmonization were very ambitious. The aim was not ... Since the beginning of 60s of the 20th century the European Community has been voicing its concerns about the need for tax harmonization. First attitudes towards tax harmonization were very ambitious. The aim was not only to reach structural harmonization in the Member States, but also harmonization of tax base and tax rates. The article explores the nature and conditions of the harmonization process while addressing its legislative modifications. The article analyses and compares the most important indirect taxes (value added tax, excise duties) in the Member States of the EU. Despite decades of efforts to harmonize taxes countries continuously apply national taxes. Heads of the Union argue that this approach can lead to disintegration in the future. 展开更多
关键词 harmonization COMPETITION VAT (value added tax) excise duty
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Minutes of the Second WHO Consultation Meeting on Harmonization of Traditional and Modern Medicine
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作者 Prof.XIEZhufan 《Chinese Journal of Integrated Traditional and Western Medicine》 2003年第4期313-314,共2页
关键词 WHO Minutes of the Second WHO Consultation Meeting on harmonization of Traditional and Modern Medicine of on
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A Ship of Fools Failing Harmonization and the Disregard of Principles of Finance
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作者 Tomas Hulko 《Cultural and Religious Studies》 2017年第1期30-40,共11页
The development of the EU according to the strategy Europe 2020 has encountered significant difficulties. It was caused in great part by the underestimation and in some cases total ignorance towards the principles of ... The development of the EU according to the strategy Europe 2020 has encountered significant difficulties. It was caused in great part by the underestimation and in some cases total ignorance towards the principles of financial science. The paper discusses the absence of financial-law based point of view regarding the future development scenarios until 2020. Then the five goals set out by the strategy are examined. The critical state of finance in the EU shows the fruitlessness of all the harmonization efforts lately. The authors of fake statistics and fake misleading prognoses have not been brought to justice. The causes of the crisis have been wrongly identified. We are losing our wealth, which generations had labored to accumulate. We are actively giving up our civil rights and the security of our citizens to create a more pleasant environment for Saudi Arabia. During this effort we have contributed to the destruction of millions of lives in the Middle East. We are the only ones in the world still lending our trust to rating agencies that deliberately derailed the global economy in the pursuit of extra profit. 展开更多
关键词 Europe 2020 strategy evaluation harmonization financial law growth scenarios headline targets crisis management synergles
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Accounting Harmonization for the Assessment of the Public Expenditure in Healthcare Service: Evidence From the Italian Experience
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作者 Niccol6 Persiani Alberto Romolini +1 位作者 Fabrizio Rossi Claudia Galanti 《Journal of Modern Accounting and Auditing》 2013年第8期1005-1017,共13页
The introduction of the New Public Management (NPM) has not bridged the differences among the various European accounting traditions. In Italy, in particular, there are still different accounting methods in all publ... The introduction of the New Public Management (NPM) has not bridged the differences among the various European accounting traditions. In Italy, in particular, there are still different accounting methods in all public sectors. In the healthcare system, these differences have emerged more strongly. The recent Italian reform on accounting harmonization seems to be the answer to this accounting disharmony and represents a means of controlling public expenditure. This study aims to analyze the consolidated financial statement and the consolidated cash flow statement of the regional healthcare system as a new tool for the accounting harmonization. This paper is divided into two logical parts: In the first part, the authors analyze how the new accounting model is evolving under the current reform; in the second part, the authors analyze the consolidated financial statement and the consolidated cash flow statement that has been applied experimentally over the last two years in the Umbria Region. 展开更多
关键词 accounting harmonization consolidated financial statement consolidated cash flow statement healthcare public expenditure
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Harmonization of Spatial Discrepancies from Land-related Data and Information Using Geospatial Technologies: A Case Study of OI-Kalou Township in Nyandarua County, Kenya
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作者 Paul K. Tower Tubei Patroba Achola Odera 《Journal of Geodesy and Geomatics Engineering》 2016年第2期37-51,共15页
This paper explores potential of Remote Sensing and Geospatial Information Systems as viable tools for data collection, processing, transformation and adjustment of cadastral data discrepancies often noted by geospati... This paper explores potential of Remote Sensing and Geospatial Information Systems as viable tools for data collection, processing, transformation and adjustment of cadastral data discrepancies often noted by geospatial practitioners during rasterization and vectorization of land related data. Necessary datasets were collected employing main approach/procedure of scanning, georeferencing, digitization, transformation and analysis in that order, to amalgamate and harmonize all datasets into one common projection and coordinate system (Universal Transverse Mercator (UTM) on Arc-Datum 1960). Discrepancies in derived areas against recorded values in land registries were noted, smaller parcels exhibited smaller discrepancies and vice versa. Discrepancies were found to be directly proportional to the parcel areas/sizes although large parcels (〉 1000 m2) exhibited abnormally high discrepancies. This procedure yielded systematic discrepancies that could be minimized by use of a fifth order polynomial. Resultant residuals were found to be tolerably low and could be ignored for small parcels (〈 1000 m2). Final outputs included automated GIS geodatabase cadastre, containing cadastral attributes harmonized to one projection and coordinate system that can be overlaid to other datasets from engineering design and construction works, geological and geotechnical investigation surveys, etc. tied to Remote Sensing data without the requirement of further transformations. 展开更多
关键词 Coordinate transformation GEOREFERENCING projection systems cadastre spatial data discrepancies spatial data harmonization.
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H_(3)Se in the Imˉ3m Phase:High-Pressure Superconductor with T_(c) Reaching 200K at 64GPa Mediated by Anharmonic Phonons
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作者 Yao Ma Mingqi Li +3 位作者 Wenjia Shi Vei Wang Pugeng Hou Mi Pang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第12期159-165,共7页
Hydrogen-based compounds have attracted significant attention in recent years due to the discovery of conventional superconductivity with high critical temperature under high pressure,rekindling hopes for finding room... Hydrogen-based compounds have attracted significant attention in recent years due to the discovery of conventional superconductivity with high critical temperature under high pressure,rekindling hopes for finding roomtemperature superconductors.In this study,we investigated the vibrational and superconducting properties of H_(3)Sein the Im ̄3m phase under pressures of 50-200GPa.Our approach combines the stochastic self-consistent harmonic approximation and first-principles calculations to account for the quantum and anharmonic effects of ions.According to the results,these effects significantly modify the crystal structure,increasing the inner pressure by approximately 8GPa compared to situations in which they are ignored.The phonon spectra suggest that when these effects are considered,the crystal stabilizes at pressures as low as approximately 61GPa,which is significantly lower than the previously predicted value of over 100GPa.Our calculations also highlight the critical role of quantum and anharmonic effects on the electron-phonon coupling properties.Neglecting these factors can result in a significant overestimation of the superconducting critical temperature(T_(c))by approximately 4K(200GPa)to 25K(125GPa).With anharmonic phonons,the T_(c) calculated from the Migdal-Eliashberg equations reaches 200K(μ⋆=0.1,λ=4.1)as the pressure decreases to 64GPa,indicating that the crystal is a rare high-Tc superconductor at moderate pressures. 展开更多
关键词 harmonIC critical SUPERCONDUCTOR
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Bunching enhancement for coherent harmonic generation by using phase merging effects
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作者 Ke Feng Kangnan Jiang +3 位作者 Runshu Hu Shixia Luan Wentao Wang Ruxin Li 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第5期10-21,共12页
In this paper,promising but simple schemes are investigated to enhance the micro-bunching of relativistic electron beams for coherent harmonic generation(CHG)by using phase merging effects.In contrast to the standard ... In this paper,promising but simple schemes are investigated to enhance the micro-bunching of relativistic electron beams for coherent harmonic generation(CHG)by using phase merging effects.In contrast to the standard CHG scheme,two specially designed dispersion sections(DSs)are adopted with the DS-modulator–DS configuration.The phase space of the e beam is appropriately coupled in the first DS,and the electrons within one seed wavelength can merge to the same phase with a matched second DS.Micro-bunching of the e beam can thus be enhanced by a large margin with much higher-harmonic components.Taking e beams from laser wakefield accelerators(LWFAs)as an example,start-to-end simulations are performed to show the effectiveness and robustness of the proposed schemes with several configurations.The beam current can be optimized to several tens to hundreds of kiloamperes,and the radiation power reaches hundreds of megawatts in the extreme ultraviolet regime within a 3.5 m-long beamline.The proposed schemes offer new opportunities for future compact free-electron lasers driven by LWFAs and provides prospects for truly compact and widely applicable systems. 展开更多
关键词 MODULATOR harmonIC PHASE
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High-order harmonic generation of ZnO crystals in chirped and static electric fields
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作者 张玲玉 何永林 +5 位作者 谢卓璇 高芳艳 徐清芸 葛鑫磊 罗香怡 郭静 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期335-343,共9页
High harmonic generation in ZnO crystals under chirped single-color field and static electric field are investigated by solving the semiconductor Bloch equation(SBE). It is found that when the chirp pulse is introduce... High harmonic generation in ZnO crystals under chirped single-color field and static electric field are investigated by solving the semiconductor Bloch equation(SBE). It is found that when the chirp pulse is introduced, the interference structure becomes obvious while the harmonic cutoff is not extended. Furthermore, the harmonic efficiency is improved when the static electric field is included. These phenomena are demonstrated by the classical recollision model in real space affected by the waveform of laser field and inversion symmetry. Specifically, the electron motion in k-space shows that the change of waveform and the destruction of the symmetry of the laser field lead to the incomplete X-structure of the crystal-momentum-resolved(k-resolved) inter-band harmonic spectrum. Furthermore, a pre-acceleration process in the solid four-step model is confirmed. 展开更多
关键词 high-order harmonic generation the semiconductor Bloch equation k-resolved inter-band harmonic spectrum four-step semiclassical model
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