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Two types of uranium mineralization in Gulcheru quartzite:Fracture-controlled in Ambakapalle area and litho-controlled in Tummalapalle area,Cuddapah Basin,Andhra Pradesh,India 被引量:3
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作者 Sukanta Goswami Pradeep Kumar Upadhyay +2 位作者 Bhaskaran Saravanan V Natarajan Mohan Babu Verma 《China Geology》 2019年第2期142-156,共15页
The Cuddapah Basin in southern India has a potential for uranium mineralization due to some favorable factors such as its temporal, stratigraphic and tectonic settings. Systematic exploration program conducted by the ... The Cuddapah Basin in southern India has a potential for uranium mineralization due to some favorable factors such as its temporal, stratigraphic and tectonic settings. Systematic exploration program conducted by the Atomic Minerals Directorate for Exploration and Research (AMD) within the Cuddapah Basin resulting in the recognition of distinct types of uranium mineralization, viz., strata bound type, fracture/shear-controlled type and tabular type. The Gulcheru Formation which is the lowermost unit of the Cuddapah Basin is dominantly arenitic in nature. During the exploration works, a number of uranium anomalies were identified with dimensions ranging from 1 m to 1.5 km. Gulcheru quartzite hosted uranium mineralization is intermittent and inconsistent in nature. The anomalous outcrops are distributed over a strike length of ca. 60 km between Gandi in the SE and Ambakapallein the NW. Presently, two different types of uranium mineralization are characterized on the basis of field observations, mapping and structural interpretation, petro-mineralogy and geochemistry. Although the host rock is same for both types, the mechanism of uranium enrichment is totally different. The Ambakapalle uranium mineralization is controlled by fault zone and associated hydrothermal activity. Whereas, the Tummalapalle uranium mineralization is litho-controlled in nature influenced by suitable four ‘P’ factors, i.e., provenance, porositypermeability, precipitation and preservation. The geochemical characterization of Gulcheru quartzite suggest a passive margin type of provenance setting. Petro-mineralogically the quartz arenite suggests enough textural as well as mineralogical maturity. Ambakapalle quartzite is slightly strained and deformed due to faulting. Analysis of selected samples recorded 0.01% to 0.048% U3O8 and <0.01% ThO2. Petrographic observation revealed that the anomalies were appeared due to secondary uranium minerals occurring as surficial encrustations, fracture filling and lesser irregular patches. Structural analysis suggests the mineralization along E-W trace slip fault is possibly consistent in sub-surface. Tummalapalle quartzite is relatively less deformed arenitic in nature with significant enrichment in MREE. The genetic models for the two types of mineralization is totally different. 展开更多
关键词 Uranium MINERALIZATION Fracture-controlled MINERALIZATION Litho-contralled MINERALIZATION Gulcheru QUARTZITE Hydrothermal ALTERATION Andhra Pradesh INDIA
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Effect of methane content and the oscillating electric field between electrodes on atmospheric Ar/methane plasma jet and DLC coating deposition 被引量:1
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作者 Reza SAFARI Farshad SOHBATZADEH 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第8期76-89,共14页
In this work,the effects of the methane gas flow and the internal oscillating electric field between electrodes on radio-frequency(RF)atmospheric pressure argon/methane plasma jet and process of diamond-like carbon(DL... In this work,the effects of the methane gas flow and the internal oscillating electric field between electrodes on radio-frequency(RF)atmospheric pressure argon/methane plasma jet and process of diamond-like carbon(DLC)film deposition have been investigated.Properties of RF atmospheric Ar/methane plasma jet such as active species density,length,electron temperature,appearance and ionization process of argon/methane plasma jet are changed due to the changing of methane flow content and electric field vector and its gradient.With increasing methane flow,the formation of C2 hydrocarbon and CH band content is decreased because injected electrical energy to a mixture of Ar/methane gases is insufficient to stabilize the ionization process of methane gas and the electrical-chemical reaction rate is decreased.With shortening the gas gap between two electrodes,electric field strength and its gradient are increased leading to more energy injection to the electron.Electrical-chemical reactions are strengthened leading to increasing the CH band content.These phenomena introduce the Ar/methane plasma jet in different modes causing to deposit the DLC film with different structures and properties.With using quartz glass and alumina ceramic as dielectric barriers tubes,RF atmospheric pressure Ar/methane plasma jet has been used to deposit DLC coating in different modes.Increasing methane content and shortening the gas gap leads to decreasing sp3 bonded content and the quality of the deposited film. 展开更多
关键词 RF ATMOSPHERIC plasma METHANE flow electric field
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Phase Control of Transient Optical Properties of Double Coupled Quantum-Dot Nanostructure via Gaussian Laser Beams 被引量:1
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作者 J.Shiri F.Shahi +1 位作者 M.R.Mehmannavaz L.Shahrassai 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第2期29-33,共5页
We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorpt... We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorption and dispersion of the probe field can be dramatically influenced by the relative phase between applied fields and intensity of the Gaussian laser beams.Transient and steady-state behaviors of the probe field absorption and dispersion are discussed to estimate the required switching time.The estimated range is between 5-8 ps for subluminal to superluminal light propagation. 展开更多
关键词 Phase Control of Transient Optical Properties of Double Coupled Quantum-Dot Nanostructure via Gaussian Laser Beams QDs
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Tectonic Setting of the Kadiri Schist Belt, Andhra Pradesh, India
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作者 Sukanta GOSWAMI Pradeep K.UPADHYAY +1 位作者 Purnajit BHATTACHARJEE Malaiandi G.MURUGAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期1992-2006,共15页
Plate tectonic activity has played a critical role in the development of petrotectonic associations in the Kadiri schist belt. The calc alkaline association of basalt, andesite, dacite and rhyolite (BADR) is the sig... Plate tectonic activity has played a critical role in the development of petrotectonic associations in the Kadiri schist belt. The calc alkaline association of basalt, andesite, dacite and rhyolite (BADR) is the signature volcanic rock suite of the convergent margin. The N-S belt has gone below the unconformity plane of Cuddapah sediments. In the northern part geochemical and structural attributes of the Kadiri greenstone belt is studied along with microscopic observations of selected samples. Harker diagram plots of major elements generally indicate a liquid line of descent from a common source, such that BADR rocks are derived from a common parent magma of basaltic to andesitic composition. These calc-alkaline volcanic rocks are formed at convergent margins where more silicic rocks represent more highly fractionated melt. All the litho-units of this greenstone belt indicate crush and strain effects. The stretched pebbles in the deformed volcanic matrix with tectonite development along with associated greenschist facies metamorphism, alteration and hydration is remarkable. Flow foliation plane with N-S strike and very low angle (5~ to 10~) easterly dip and N-S axial planar schistosity formed due to later phase isoclinal folding can be clearly identified in the field. Basic intrusives are quite common in the surrounding area. All the observations including the field setting and geochemistry clearly demonstrate ocean-continent subduction as the tectonic environment of the study area. 展开更多
关键词 Kadiri schist belt TECTONICS Unconformity contact Ocean-continent subduction Andhra Pradesh Cuddapah basin Greenstone belt
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A study of PFBR auxiliary neutron source strength activation and its variability with respect to the neutron spectrum and 123Sb capture cross section
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作者 G.Pandikumar D.Sunil Kumar +4 位作者 M.M.Shanthi Bagchi Subhrojit A.John Arul D.Venkata Subramanian Rajeev Ranjan Prasad 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第8期114-122,共9页
In fast reactors, the inherent neutron source strength is often insufficient for monitoring the reactor start-up operation with ex-core detectors. To increase the subcritical neutron flux, an auxiliary neutron source ... In fast reactors, the inherent neutron source strength is often insufficient for monitoring the reactor start-up operation with ex-core detectors. To increase the subcritical neutron flux, an auxiliary neutron source subassembly(SSA) is generally used to overcome this problem. In this study, the estimated neutron source strength and detector count rate of an antimony-beryllium-based SSA are obtained using the deterministic transport code DORT and Monte Carlo calculations. Because the antimony activation rate is a critical parameter, its sensitivity to the capture cross section and neutron flux spectrum is studied. The reaction cross section sensitivity is studied by considering data from different evaluated nuclear data files.It is observed that, because of the variation in the cross sections from different evaluated nuclear data files, the values of the saturation gamma(> 1.67 MeV) activity and neutron strength predicted by ORIGEN2 lie within ±2%.The obtained antimony activation rate and sensitivity to the neutron flux are partially validated by irradiating samples of antimony in the KAMINI reactor. The average onegroup capture cross sections of bare and cadmium-covered 123Sb samples obtained by the ratio method are 4.0 and 1.78 b, respectively. The results of the calculation predicting the activated neutron source strength as a function of operating time and sensitivity to the neutron spectrum in the irradiation region are also presented. 展开更多
关键词 Fast reactors NEUTRON source Coremonitoring NEUTRON and GAMMA transport Antimonyactivation Material depletion
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Study of Current Sheath Velocity and Its Distribution Using Tridimensional Magnetic Probe in Sahand Plasma Focus
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作者 M.A.MOHAMMADI S.HEDYEH 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第5期353-357,共5页
The current sheath velocity in 0.25 Torr gas pressure of Filippov type plasma focus is studied experimentally. By using two tridimensional magnetic probes on top of the anode surface, the current sheath velocity is me... The current sheath velocity in 0.25 Torr gas pressure of Filippov type plasma focus is studied experimentally. By using two tridimensional magnetic probes on top of the anode surface, the current sheath velocity is measured for argon, oxygen and nitrogen. Additionally, the effect of charging voltage on the current sheath velocity is studied in both axial and radial phases. We found that, the maximum current sheath velocities at both radial and axial phases are respectively 4.33 ± 0.28 (cm/μs) and 3.92 ± 0.75 (cm/μs) with argon as the working gas at 17 kV. Also, the minimum values of current sheath velocity are 1.48 ± 0.15 (cm/μs) at the radial phase and 1.14 ± 0.09 (cm/μs) at the axial phase with oxygen at 12 kV. The current sheath velocity at the radial phase is higher than that at the axial phase for all gases and voltages. In this study, variation of the full width half maximum (FWHM) of magnetic probe signals with voltage is investigated for different gases at radial and axial phases. 展开更多
关键词 plasma focus tridimensional magnetic probe current sheath dynamics
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Micelle Mediated Extraction of Iron and Its Determination in Geological, Geochemical, Hydrogeochemical, Biogeochemical and Process Solutions
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作者 Pranab Kumar Tarafder Rabin Kumar Mondal 《American Journal of Analytical Chemistry》 2012年第5期339-346,共8页
Iron irrespective of its valency states forms bluish 1:1 cationic, bluish-violet 1:3 neutral and purple 1:3 anionic complexes with 2,3-dihydroxynaphthalene, at pH 2 - 3, 4 - 5 and 8 - 10, respectively. The cationic bl... Iron irrespective of its valency states forms bluish 1:1 cationic, bluish-violet 1:3 neutral and purple 1:3 anionic complexes with 2,3-dihydroxynaphthalene, at pH 2 - 3, 4 - 5 and 8 - 10, respectively. The cationic bluish complex is highly insensitive and not extractable in organic solvents. Similarly, the bluish violet 1:3 neutral complex is of moderate sensitivity, and it is extractable in organic solvents with reduced sensitivity. The purple 1:3 anionic complex is as such not extractable in any organic solvents. However, in the surfactant medium of the cationic surfactant, cetyltrimethylammonium bromide it is extractable in organic solvents with enhanced sensitivity. The 1:3 anionic complex which is extractable in organic solvents as an ion associate in the presence of cetyltrimethyl ammonium bromide is chosen for application to Silicate rocks, Minerals, Soils, Stream sediments, Concentrates, Tobacco leaves, Cigarettes and Waters, for accurate and sensitive determination of iron owing to facile extraction of iron, enhanced sensitivity high selectivity and better reproducibility of results. The present paper describes a systematic study on the development of an extraction spectrophotometric method for the determination of iron in samples of diverse matrices. 展开更多
关键词 2 3-Dihydroxynaphthalene CETYLTRIMETHYLAMMONIUM Ion SPECTROPHOTOMETRIC Solvent EXTRACTION Determination
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Producing High Intense Attosecond Pulse Train by Interaction of Three-Color Pulse and Overdense Plasma
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作者 M.Salehi S.Mirzanejad 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第5期52-55,共4页
Amplifying the attosecond pulse by the chirp pulse amplification method is impossible. Furthermore, the intensity of attosecond pulse is low in the interaction of laser pulse and underdense plasma. This motivates us t... Amplifying the attosecond pulse by the chirp pulse amplification method is impossible. Furthermore, the intensity of attosecond pulse is low in the interaction of laser pulse and underdense plasma. This motivates us to propose using a multi-color pulse to produce the high intense attosecond pulse. In the present study, the relativistic interaction of a three-color linearly-polarized laser-pulse with highly overdense plasma is studied. We show that the combination of ω1, ω2 and ω3 frequencies decreases the instance full width at half maximum reflected attosecond pulse train from the overdense plasma surface. Moreover, we show that the three-color pulse increases the intensity of generated harmonics, which is explained by the relativistic oscillating mirror model. The obtained results demonstrate that if the three-color laser pulse interacts with overdense plasma, it will enhance two orders of magnitude of intensity of ultra short attosecond pulses in comparison with monochromatic pulse. 展开更多
关键词 Producing High Intense Attosecond Pulse Train by Interaction of Three-Color Pulse and Overdense Plasma
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Effect of electrical discharge in water on concentration of nitrate solution
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作者 F Sohbatzadeh H Bagheri R Safari 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期305-312,共8页
In this work, the effect of electrical discharge on nitrate concentration is considered in aqueous solution. The atmospheric pressure plasma was produced by a high-voltage power supply at 27 k Hz using pin-to-pin conf... In this work, the effect of electrical discharge on nitrate concentration is considered in aqueous solution. The atmospheric pressure plasma was produced by a high-voltage power supply at 27 k Hz using pin-to-pin configuration. Air, argon,and argon/methane mixture were used to study the working gas effect. UV-VIS spectroscopy and ion chromatography were used to analyze the effect of the electrical discharge on nitrate concentration in deionized water. Optical emission spectroscopy(OES) was applied to diagnose active species inside and on the surface of the deionized water solution. The results of the present work showed that the atmospheric pressure electric discharge with air increases nitrate concentration while it remains constant using argon and argon/methane electrical discharges. It was also revealed that in the presence of air, the electrical discharge reduces p H, acidifying the solution and increasing solution conductivity due to production of extra nitrate ions. On the other hand, argon electrical discharge increases p H and conductivity due to production of OHion in water. 展开更多
关键词 electric discharge nitrate solution optical spectroscopy
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Development of a Novel Media-independent Communication Theology for Accessing Local&Web-based Data:Case Study with Robotic Subsystems
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作者 Debanik Roy 《Artificial Intelligence Advances》 2021年第1期1-35,共35页
Realizing media independence in today’s communication system remains an open problem by and large.Information retrieval,mostly through the Internet,is becoming the most demanding feature in technological progress and... Realizing media independence in today’s communication system remains an open problem by and large.Information retrieval,mostly through the Internet,is becoming the most demanding feature in technological progress and this web-based data access should ideally be in user-selective form.While blind-folded access of data through the World Wide Web is quite streamlined,the counter-half of the facet,namely,seamless access of information database pertaining to a specific end-device,e.g.robotic systems,is still in a formative stage.This paradigm of access as well as systematic query-based retrieval of data,related to the physical enddevice is very crucial in designing the Internet-based network control of the same in real-time.Moreover,this control of the end-device is directly linked up to the characteristics of three coupled metrics,namely,‘multiple databases’,‘multiple servers’and‘multiple inputs’(to each server).This triad,viz.database-input-server(DIS)plays a significant role in overall performance of the system,the background details of which is still very sketchy in global research community.This work addresses the technical issues associated with this theology,with specific reference to formalism of a customized DIS considering real-time delay analysis.The present paper delineates the developmental paradigms of novel multi-input multioutput communication semantics for retrieving web-based information from physical devices,namely,two representative robotic sub-systems in a coherent and homogeneous mode.The developed protocol can be entrusted for use in real-time in a complete user-friendly manner. 展开更多
关键词 Web COMMUNICATION Internet robotics Information retrieval Media Sensory system Database
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Analysis of Long Term Variation of the Total Column and Tropospheric Ozone over the Indian Region
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作者 C. T. Resmi T. Nishanth +2 位作者 P. S. Vijoy M. K. Satheesh Kumar M. Balachandramohan 《Atmospheric and Climate Sciences》 2021年第1期194-213,共20页
Ozone plays a significant part in regulating climate change and the chemical characteristics of the atmosphere. Changes in atmospheric ozone can be studied in more detail using ground-based and satellite-based instrum... Ozone plays a significant part in regulating climate change and the chemical characteristics of the atmosphere. Changes in atmospheric ozone can be studied in more detail using ground-based and satellite-based instruments. Studies on the long-term global changes in total column ozone have begun more than three-decade ago using satellite data. The main objective of this work is to analyze the Total Column Ozone (TCO) variations, and tropo-spheric ozone variations over different twenty locations in the Indian sub-continent by using Total Ozone Mapping Spectrometer (TOMS) and AURA OMI/MLS data. The long-term analysis of total column ozone is divided into two phases (1979-1994 and 2005-2018), and tropospheric ozone for one phase (2005-2018) in order to detect changes in the ozone trend pattern. The results of linear regression analysis show a declining trend of total column ozone, and an increasing trend of tropospheric ozone over the selected locations. The impact of wind pattern on the variation of ozone has been analyzed by using NCEP reanalysis data, and found that wind patterns played a prominent role in spatial and temporal changes in total and tropospheric ozone distribution over the subcontinent. Latitudinal variation of total column ozone from Nagarcoil to Anantanag has also been studied for the years 1979, 1994, 2005, and 2018, which indicates an increase in ozone concentration with latitude. 展开更多
关键词 OZONE Indian Sub-Continent Seasonal Variation Satellite Data Wind Profile
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Biochemical Composition and Anticancer Effect of Different Seaweed Species(In-vitro and In-vivo Studies)
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作者 T·H·Ranahewa A·D·Premarathna +3 位作者 R·M·K·K· V·Wijewardana A·P·Jayasooriya R·P·V·J·Rajapakse 《Sustainable Marine Structures》 2019年第2期5-11,共7页
Seaweed is an enormous resource comprised with natural bioactive compounds with several therapeutic effects including anticancer activity.In this context,the biochemical composition of seaweed plays a major role.Many ... Seaweed is an enormous resource comprised with natural bioactive compounds with several therapeutic effects including anticancer activity.In this context,the biochemical composition of seaweed plays a major role.Many biochemical compounds isolated from seaweed,fractions of seaweed and crude extracts has revealed ability of seaweed to fight against several cancer types.In this contrast seaweed extracts inhibit cancer cell growth and proliferation by inducing apoptosis and by inhibiting metastasis activity.In this review,biochemical and anticancer properties of seaweeds are discussed and this will provide the basic information to develop a novel chemotherapeutic drug to challenge the cancers. 展开更多
关键词 SEAWEED BIOCHEMICAL Bioactive ANTICANCER APOPTOSIS
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印度南部安得拉邦部分地区富含Zr、Hf、U、Th和稀土元素的古元古代钾质花岗岩
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作者 Yamuna SINGH 《地质学报》 EI CAS CSCD 北大核心 2004年第4期575-576,共2页
关键词 ZR HF U TH 稀土元素 古元古代 钾质花岗岩
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离子和冷却电子重组的高分辨谱研究(英文)
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作者 R. Schuch N. Eklw +8 位作者 M. Fogle E.Lindroth S. Madzunkov T. Mohamed D. Nikolic P.Glans H. Danared A. Kllberg A. Paal 《原子核物理评论》 CAS CSCD 北大核心 2002年第2期136-139,共4页
给出了在CRYRING重离子储存环上测量到的在很低能量下电子与离子重组的最新实验结果和有关速率系数增强的新的数据 .主要讨论类锂、类钠和类铜离子的共振双电子重组的新近测量结果 ,以及从这些共振谱中所导出的非常精确的离子能级劈裂... 给出了在CRYRING重离子储存环上测量到的在很低能量下电子与离子重组的最新实验结果和有关速率系数增强的新的数据 .主要讨论类锂、类钠和类铜离子的共振双电子重组的新近测量结果 ,以及从这些共振谱中所导出的非常精确的离子能级劈裂值 ,从而将严格检验相对论效应、电子关联效应和量子电动力学效应 .其中 ,对类锂Kr3 3 + 离子 2s1/2 能级Lamb移位的确定精度达到了0 .1%. 展开更多
关键词 离子 冷却电子 高分辨谱 重组速率系数 共振双电子重组 量子电动力学效应 冷却存储环 重离子储存环 电子关联效应
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Arriving at a correlation between the flagellar arrangement and multicellularity
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作者 Suruchi Jamkhedkar Jyotsna Dongerdive +2 位作者 Kavita Jain Siby Abraham Jacinta S. D’Souza 《Advances in Bioscience and Biotechnology》 2013年第1期93-102,共10页
Cilia and flagella are organelles of motility that enable cells to swim or move liquid over its surface. An exhaustive literature survey for the presence of the organelle in organisms across phyla showed that most ani... Cilia and flagella are organelles of motility that enable cells to swim or move liquid over its surface. An exhaustive literature survey for the presence of the organelle in organisms across phyla showed that most animal cells harbor cilia in contrast to very few fungal cells. While this was not unexpected, it was the position and arrangement of this organelle in each cell that intrigued our attention. Natural selection might have favored motility over chemotaxis;and it would have done so to evolve a stable structure that could have undergone an optimization process requiring a precise geometry in the shape of cells and the structure that would help cells to move. The positioning of such a structure would play a pre-dominant role in optimal motility. It is now known that the flagellar position of a cell is a genetically distinct trait, occasionally used in phylogeny of bacteria, distributed in distinguishing patterns over cellular surface, but basically are of two types, either polar (one flagellum arising from one pole per cell) or peritrichous (lateral flagella distributed over the entire cell surface). Irrespective of the cellular habitat, flagella origin, ultrastructure and proteome, the present investigation surveyed 26 sub-types of flagellar arrangements from as many species as possible. A peculiar pattern ensued-Prokaryotes harbored predominantly polar and peritrichous types;eukaryotes showed a mere change of the peritrichous one. These numbers when used to create a Similarity tree depicted a similarity distance of 14 between the Eubacteria and Archaebacteria forming the first neighborhood;Protozoans, Algae, Fungi, Plantae and Animalia formed a second neighborhood. We offer a working hypothesis for this pattern and the gradual shift in the flagellar arrangement from polar, peritrichous, sub-apical, and apical to lateral throughout evolution. 展开更多
关键词 FLAGELLA CILIA POLAR Peritrichous MULTICELLULARITY FLAGELLAR Arrangement
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First principles calculation of spin-related quantities for point defect qubit research 被引量:4
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作者 Viktor Ivády Igor A.Abrikosov Adam Gali 《npj Computational Materials》 SCIE EI 2018年第1期32-44,共13页
Point defect research in semiconductors has gained remarkable new momentum due to the identification of special point defects that can implement qubits and single photon emitters with unique characteristics.Indeed,the... Point defect research in semiconductors has gained remarkable new momentum due to the identification of special point defects that can implement qubits and single photon emitters with unique characteristics.Indeed,these implementations are among the few alternatives for quantum technologies that may operate even at room temperature,and therefore discoveries and characterization of novel point defects may highly facilitate future solid state quantum technologies.First principles calculations play an important role in point defect research,since they provide a direct,extended insight into the formation of the defect states.In the last decades,considerable efforts have been made to calculate spin-dependent properties of point defects from first principles.The developed methods have already demonstrated their essential role in quantitative understanding of the physics and application of point defect qubits.Here,we review and discuss accuracy aspects of these novel ab initio methods and report on their most relevant applications for existing point defect qubits in semiconductors.We pay attention to the advantages and limitations of the methodological solutions and highlight additional developments that are expected in the near future.Moreover,we discuss the opportunity of a systematic search for potential point defect qubits,as well as the possible development of predictive spin dynamic simulations facilitated by ab initio calculations of spin-dependent quantities. 展开更多
关键词 DEFECT QUANTITIES PRINCIPLES
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Ab initio theory of the negatively charged boron vacancy qubit in hexagonal boron nitride 被引量:4
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作者 Viktor Ivády Gergely Barcza +5 位作者 GergőThiering Song Li Hanen Hamdi Jyh-Pin Chou Örs Legeza Adam Gali 《npj Computational Materials》 SCIE EI CSCD 2020年第1期1332-1337,共6页
Highly correlated orbitals coupled with phonons in two-dimension are identified for paramagnetic and optically active boron vacancy in hexagonal boron nitride by first principles methods which are responsible for rece... Highly correlated orbitals coupled with phonons in two-dimension are identified for paramagnetic and optically active boron vacancy in hexagonal boron nitride by first principles methods which are responsible for recently observed optically detected magnetic resonance signal.Here,we report ab initio analysis of the correlated electronic structure of this center by density matrix renormalization group and Kohn-Sham density functional theory methods.By establishing the nature of the bright and dark states as well as the position of the energy levels,we provide a complete description of the magneto-optical properties and corresponding radiative and non-radiative routes which are responsible for the optical spin polarization and spin dependent luminescence of the defect.Our findings pave the way toward advancing the identification and characterization of room temperature quantum bits in two-dimensional solids. 展开更多
关键词 BORON HEXAGONAL VACANCY
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Design and Simulation of a Highly Sensitive SPR Optical Fiber Sensor 被引量:1
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作者 Motahare Sadat HOSEINIAN Mohammad Agha BOLORIZADEH 《Photonic Sensors》 SCIE EI CAS CSCD 2019年第1期33-42,共10页
An idea of the surface plasmon resonance(SPR)has been utilized for the design of highly sensitive sensors based on the wagon-wheel fiber technology.Such sensors are sensitive to changes in the refractive index of samp... An idea of the surface plasmon resonance(SPR)has been utilized for the design of highly sensitive sensors based on the wagon-wheel fiber technology.Such sensors are sensitive to changes in the refractive index of sample analyte.In this study,a three-strut wagon-wheel structure,coated with the gold layer of nano-sized thickness,has been proposed as the SPR sensor.Finite element method is employed to simulate and tune the proposed SPR's design,which leads to a highly sensitive and multichannel plasmonic sensor with the ability for a dual reading on a single analyte or simultaneous identification of two analytes.In this design,suitable thickness values for the gold layer and core struts are determined.Sensitivities of the detector due to the first resonance peak, second resonance peak,and the difference in resonance peaks are calculated to be 1120nm/RIU, 1540nm/RIU,and 420nm/RIU,respectively,when analytes are placed in all three channels of the fiber.Sensitivity of the detector with respect to the second resonant peak for analyte in Channels 2 and 3 is also found to be 1252nm/RIU when Channel 1 is filled with the reference.The sensitivity and resolution of the sensor increase as the refractive index of the analyte increases by almost a linear proportion.If the sensor is utilized to detect the difference in two peaks,it would substantially reduce the noise,and the best result is expected.The thicknesses of the struts and the gold layer are proper parameters to be tuned in designing the detector. 展开更多
关键词 PLASMONICS surface plasmon-polaritons sensor wagon-wheel fiber
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Operational effects of the UNOT gate on classical and quantum correlations 被引量:1
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作者 Kuan Zhang Jiajun Ma +4 位作者 Xiang Zhang Jayne Thompson Vlatko Vedral Kihwan Kim Mile Gu 《Science Bulletin》 SCIE EI CSCD 2018年第12期765-770,共6页
The NOT gate that flips a classical bit is ubiquitous in classical information processing.However its quantum analogue,the universal NOT(UNOT) gate that flips a quantum spin in any alignment into its antipodal counter... The NOT gate that flips a classical bit is ubiquitous in classical information processing.However its quantum analogue,the universal NOT(UNOT) gate that flips a quantum spin in any alignment into its antipodal counterpart is strictly forbidden.Here we explore the connection between this discrepancy and how UNOT gates affect classical and quantum correlations.We show that while a UNOT gate always preserves classical correlations between two spins,it can non-locally increase or decrease their shared discord in ways that allow violation of the data processing inequality.We experimentally illustrate this using a multi-level trapped ^(171)Yb^+ ion that allows simulation of anti-unitary operations. 展开更多
关键词 古典 关联 运作 信息处理 类似物 非局部 多水平 试验性
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Revisit to Two-Proton Radioactivity of 19Mg and Observation of Two-Proton Decay of 30Ar 被引量:1
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作者 徐晓栋 I.Mukha +44 位作者 L.Acosta E.Casarejos A.A.Ciemny W.Dominik J.Duénas-Díaz V.Dunin J.M.Espino A.Estradé F.Farinon H.Geissel A.Fomichev T.A.Golubkova A.Gorshkov L.V.Grigorenko Z.Janas G.Kamiński O.Kiselev R.Knbel S.Krupko M.Kuich Yu.A.Litvinov G.Marquinez-Dur'an I.Martel C.Mazzocchi C.Nociforo A.K.Ord'uz M.Pfützner S.Pietri M.Pomorski A.Prochazka S.Rymzhanova A.M.S'anchez-Benítez C.Scheidenberger P.Sharov H.Simon B.Sitar R.Slepnev M.Stanoiu P.Strmen I.Szarka M.Takechi Y.K.Tanaka H.Weick M.Winkler J.S.Winfield 《原子核物理评论》 CAS CSCD 北大核心 2016年第2期197-202,共6页
An experiment aimed to investigate the two-proton(2p) decay of the previously unknown nucleus ^(30)Ar was performed at GSI. By tracking the decay products in-flight with silicon micro-strip detectors, the 2p decays of... An experiment aimed to investigate the two-proton(2p) decay of the previously unknown nucleus ^(30)Ar was performed at GSI. By tracking the decay products in-flight with silicon micro-strip detectors, the 2p decays of ^(30)Ar were observed for the first time. For the calibration purpose, 2p decays of ^(19)Mg were also remeasured by tracking the coincident ^(17)Ne+p+p trajectories. By comparing the measured angular p-17 Ne correlations with those obtained from the corresponding Monte Carlo simulations,the simultaneous 2p decay of ^(19)Mg ground state and the sequential 2p emission of several known excited states of ^(19)Mg were confirmed. One new excited state in ^(19)Mg and two new excited states in ^(18)Na were observed. 展开更多
关键词 proton drip line decay by proton emission nuclear energy level
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