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Half-Lives of Spherical Proton emitters

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Chinese Physics Letters 2006年第4期23卷 812-814页

作者：蒋建国任中洲 Department of Physics Nanjing University Nanjing 210008 Center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion Accelerator Lanzhou 730000

The distorted-wave Born approximation （DWBA） method is used to calculate the half-lives of spherical proton emitters. The calculated results are in agreement with the experimental data, The sensitivity of the half-lives to the depth of central potential V0 is investigated by using the DWBA method. The half-lives of spherical proton emitters are insensitive to the detail of their nuclear potential.

关键词： Half-Lives emitters

A Quantum-Chemical Insight into the Role of Charge-Transfer States in Organic emitters for Electroluminescence

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CCS Chemistry 2020年第4期2卷 1256-1267页

作者： Xian-Kai Chen Department of Chemistry and Biochemistry University of ArizonaTucsonAZ 85721

The rapid progress of the design and development of efficient organic electroluminescent emitters without heavy transition metals has been achieved in recent experimental *** this minireview,based on his recent theoretical works on purely organic emitters,the author provides a quantum-chemical insight into the role of charge-transfer(CT)electronic states in electroluminescence exploiting organic thermally activated delayed fluorescence(TADF)and radical emitters.

关键词： purely organic emitters thermally activated delayed fluorescence organic radical emitters charge-transfer states Quantum-chemical insight

Comparing and evaluating the nationally determined contributions of the top six emitters under the Paris Agreement goals

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Chinese Journal of Population,Resources and Environment 2018年第3期16卷 211-219页

作者： Xunzhang Pan Jie Tao Hailin Wang Academy of Chinese Energy Strategy China University of Petroleum-Beijing Institute of Energy Environment and Economy Tsinghua University

Comparing and evaluating the Nationally Determined Contribution(NDC) is an important element in global stocktake in the post-Paris climate negotiations, aimed at closing the emissions gap with the Paris Agreement goals. To date, however, there has still been no explicit guideline or method. By applying emissions allowance allocated by 16 schemes as benchmarks, this paper tries to compare and evaluate the NDCs of the top six emitters, which jointly account for about 70% of the world's CO_2 emissions. Results show that the four developed countries' NDCs lack ambition with respect to most allocations under 2℃ and all under 1.5℃, indicating they need to substantially ratchet up their NDCs and lead elevating mitigation. Evaluating cumulative emissions is more likely to clarify the ambition and fairness of China's NDC. If considering cumulative emissions, China's NDC is aligned with the median of cumulative allowances under 2℃ and within the 1.5℃ range. The Paris Agreement invited the Parties to communicate the mid-century low emissions strategies. This paper also tries to explore the mid-century mitigation in the perspective of allocations, which might provide decision-makers with some useful information when envisaging the post-NDC mitigation.

关键词： Paris Agreement nationally determined contribution top six emitters emissions allowance allocations midcentury mitigation

Ⅲ–Ⅴ compounds as single photon emitters

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Journal of Semiconductors 2019年第7期40卷 63-74页

作者： Xu Wang Lei Xu Yun Jiang Zhouyang Yin Christopher C. S. Chan Chaoyong Deng Robert A. Taylor Key Laboratory of Electronic Functional Composite Materials of Guizhou Province Guizhou University Guiyang 550025 China Guizhou Institute of Quantum Information and Big Data Applied Technology Guiyang 550002 China Department of Physics The Hong Kong University of Science and Technology Hong Kong 999077 China Department of Physics University of Oxford Clarendon Laboratory Oxford OX1 3PU UK

Single-photon emitters (SPEs) are one of the key components in quantum information applications. The ideal SPEs emit a single photon or a photon-pair on demand, with high purity and distinguishability. SPEs can also be integrated in photonic circuits for scalable quantum communication and quantum computer systems. Quantum dots made from Ⅲ-Ⅴ compounds such as InGaAs or GaN have been found to be particularly attractive SPE sources due to their well studied optical performance and state of the art industrial flexibility in fabrication and integration. Here, we review the optical and optoelectronic properties and growth methods of general SPEs. Subsequently, a brief summary of the latest advantages in Ⅲ-Ⅴ compound SPEs and the research progress achieved in the past few years will be discussed. We finally describe frontier challenges and conclude with the latest SPE fabrication science and technology that can open new possibilities for quantum information applications.

关键词： single photon emitters solid-states quantum dots 2D materials

HYDRAULIC CHARACTERIZATIONS OF TORTUOUS FLOW IN PATH DRIP IRRIGATION EMITTER

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Journal of Hydrodynamics 2006年第4期18卷 449-457页

作者： LI Yun-kai YANG Pei-ling REN Shu-mei XU Ting-wu College of Hydraulic and Civil Engineering China Agricultural University Beijing 100083 China International College at Beijing China Agricultural University Beijing 100083 China

At present, the tortuous emitter has the most advanced performances in drip irrigation. But the theories and methods for designing its flow path have been strictly confidential and the researches on the function of practical guidance have seldom been published. Seven types of most representative tortuous emitting-pipes currently used in agricultural irrigation regions of China were chosen for investigating the geometric parameters of the flow path by means of combining high-precision microscope and AutoCAD technology. By the measurement platform developed by the authors for hydraulic performances of emitters, the free discharge rates from the 7 types of emitters were measured at 9 pressure levels of 1.5 m, 3.0 m, 5.0 m, 7.0 m, 9.0 m, 10.0 m, 11.0 m, 13.0 m and 15.0 m. Then the discharge-pressure relationship, manufacturing variation coefficient, average velocity on the cross-section of flow path and the critical Reynolds number for the flow regime transformation within the paths were analyzed in detail. The results show that both pressure-ascending work pattern and pressure-descending work pattern have some impacts on the discharge rates of tortuous emitters, but the impact level is not significant. The target pressure could be approached by repetitive applications of the two work patterns during pressure regulation. The operation under low pressures has some impacts on the hydraulic performances of emitters, but the impact level is also not significant. The classical model of the discharge-pressure relationship is suitable for the pressure range of 1.5 m -15.0 m. The Reynolds number for fluids within the 7 types of tortuous emitters ranges from Re=105 to Re =930. The critical Reynolds number for the flow regime transformation is smaller than that for the routine dimension flow path. The variation coefficient of emitter discharge rates is slightly fluctuating around a certain value within the whole pressure range.

关键词： drip irrigation emitters tortuous flow pathhydraulic performances flow characteristics

Li2SnO3 branched nano- and microstructures with intense and broadband white-light emission

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Nano Research 2019年第2期12卷 441-448页

作者： Miguel Garcia-Tecedor Javier Bartolome David Maestre Achim Trampert Ana Cremades Dpt. Fisica de Materials Facultad de CC. Fisicas Universidad Complutense de Madrid Madrid 28040 Spain Paul-Drude-Institut fur Festkorperelektronik Hausvogteiplatz 5-7 Berlin 10117 Germany Institute of Advanced Materials (INAM) Universitat Jaume I Castello 12006 Spain Dpt. Fisica de Materiales Facultad de CC. Ftsicas Universidad Complutense de Madrid Madrid 28040 Spain

Exploiting the synergy between microstructure, morphology and dimensions by suitable nanomaterial engineeri ng, can effectively upgrade the physical properties and material performances. Li2SnO3 elongated nano- and microstructures in form of belts, wires, rods and branched structures have been fabricated by a vapor-solid method at temperatures ranging from 700 to 900℃ using metallic Sn and Li2CO3 as precursors. The achievement of these new morphologies can face challenging applications for Li2SnO3, not only in the field of energy storage, but also as building blocks in optoelectronic devices. The micro? and nanostructures grown at 700 and 800℃ correspond to monoclinic Li2SnO3, while at 900℃ complex Li2S nO/SnO2 core-shell microstructures are grow n, as con firmed by X-ray diffractio n and Rama n spectroscopy. Transmission electron microscopy reveals structural disorder related to stacking faults in some of the branched structures, which is associated with the prese nee of the low-temperature phase of L12S nO3. The luminescent resp onse of these structures is domi nated by in tense emissi ons at 2, 2.5 and 3 eV, almost completely covering the whole range of the visible light spectrum. As a result, white-light emission is obtained without the need of phosphors or complex quantum well heterostructures. Enhanced functionality in applications such as in light-emitting devices could be exploited based on the high luminescenee intensity observed in some of the analysed Li2SnO3 structures.

关键词： lithium oxides white light emitters nanostructures luminescenee

Theoretical Analysis and New Formulae for Half-Lives of Proton Emission

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Chinese Physics Letters 2009年第7期26卷 81-84页

作者：张鸿飞董建敏王艳召苏昕宁王永佳蔡凌志朱天宝胡碧涛左维李君清 School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000

The proton radioactivity hMf-lives of spherical proton emitters are calculated by the cluster model with the con- tribution of a centrifugal potential barrier considered separately. The results are compared with the experimental data and other theoretical data, and good agreement is found for most nuclei. In addition, two formulae are pro- posed for the proton decay half-life of spherical proton emitters through the least squares fit to the experimental data available, and could reproduce the experimental half-lives successfully.

关键词： DECAY emitters NUCLEI

Diversity-oriented synthesis of blue emissive nitrogen heterocycles and their conjugation with carbon nano-onions

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Frontiers of Chemical Science and Engineering 2020年第1期14卷 76-89页

作者： Viviana Maffeis Lisa Moni Daniele Di Stefano Silvia Giordani Renata Riva Nano Carbon Materials Istituto Italiano di Tecnologia(IIT)10144 TorinoItaly Department of Chemistry and Industrial Chemistry University of Genova16146 GenovaItaly School of Chemical Sciences Dublin City UniversityDublin 9Ireland Department of Pharmacy University of Genova16147 GenovaItaly

The search for new fluorescent molecules for possible applications as functional p-electron systems and their conjugation with different nanomaterials is nowadays of paramount importance to broaden the availability of materials with different *** we present a diversity-oriented approach to heterocyclic luminophores based on a multicomponent Ugi reaction followed by a Pd-mediated cascade *** new molecules are coupled to carbon nano-onions,and hybrid systems represent the first example of blue emitters conjugated with these carbon nanoparticles.

关键词： carbon nano-onions multicomponent reactions blue emitters fluorescence isoquinolines

High power laser diodes of 2 μm AlGaAsSb/InGaSb type I quantum-wells

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Journal of Semiconductors 2015年第5期36卷 50-53页

作者：廖永平张宇邢军亮魏思航郝宏玥王国伟徐应强牛智川 State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

2μm A1GaAsSb/InGaSb type-I quantum-well high-power laser diodes （LDs） are grown using molec- ular beam epitaxy. Stripe-type waveguide single LD （single emitter） and array LD （four emitters） devices without facet coatings are fabricated. For the single LDs （single emitter） device, the maximum output power under contin- uous wave （CW） operation is 0.5 W at 10℃ with a threshold current density of 150 A/cm^2 and a slope efficiency of 0.17 W/A, the output powers under the pulse mode in the 5% duty cycles are much higher, up to 0.98 W. For the array LD devices, the maximum output powers are 1.02 W under the CW mode and 3.03 W under the pulse mode at room temperature.

关键词： laser diodes arrays emitters quantum wells