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High quantum yield yellow emission carbon dots for the construction of blue light blocking films
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作者 Liwen Wang Boyang Wang +2 位作者 Siyu Lu Shubo Lv Xiaoli Qu 《Chinese Chemical Letters》 2025年第2期216-221,共6页
White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual healt... White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual health.In this study,yellow-emitting carbon dots(CDs)with a quantum yield exceeding 94%were synthesized using citric acid and urea.These CDs effectively absorb blue light.By incorporating them into polystyrene,multiple films termed CDs-based blue light blocking films(CBFs)were developed,each offering different levels of blue light absorption.These CBFs exhibited excellent transparency and efficient blue light filtering capabilities.This study highlights the potential of high quantum yield CDs,which specifically absorb blue light,as foundational materials for developing light-blocking solutions against highenergy short-wavelength light. 展开更多
关键词 Carbon dots High quantum yield Controllable preparation Blue light blocking Composite film
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High thermal stability and quantum yields of green-emitting Sr_3Gd_2(Si_3O_9)_2:Tb^(3+) phosphor by co-doping Ce^(3+) 被引量:2
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作者 ZHU Yingli LIANG Yujun +3 位作者 LIU Shiqi LI Kai WU Xingya XU Rui 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第1期41-46,共6页
A series of Tb^3+ mono-doped and Ce^3+-Tb^3+ co-doped Sr3Gd2(Si3O9)2 phosphors with high thermal stability and quantum yields were successfully prepared via the solid state reaction. The as-prepared Sr3Gd2(Si3O9)2:Tb^... A series of Tb^3+ mono-doped and Ce^3+-Tb^3+ co-doped Sr3Gd2(Si3O9)2 phosphors with high thermal stability and quantum yields were successfully prepared via the solid state reaction. The as-prepared Sr3Gd2(Si3O9)2:Tb^3+ samples showed broad excitation spectrum from 250 to 400 nm and presented characteristic emission transitions ^5D4→^7FJ(J=6, 5, 4, 3) of Tb^3+ under 313 nm excitation, which were located at about 488, 541, 584 and 620 nm. The emission intensities of Tb^3+ rose steadily in Sr3Gd2(Si3O9)2 host with the increase of Tb^3+ concentration even though Gd^3+ ions were completely replaced by Tb^3+ ions. The Ce^3+ ion as a sensitizer could efficiently improve the performance of Tb^3+ ion. First, with Ce^3+ co-doping, the excitation spectrum of Tb^3+ monitored at 541 nm showed a similar band that responds to the violet emission of Ce^3+ monitored at 416 nm. Second, the quantum yields of Sr3Gd2(Si3O9)2:Tb^3+ phosphors could be enhanced from 26.6% to 80.2% by co-doping Ce^3+. Finally, the co-doping of Ce^3+ was also effective to improve the thermal stability of Sr3Gd2(Si3O9)2:Tb^3+. As the temperature rose to 150 oC, the emission intensity of Tb^3+ remained at about 83.6% of that measured at room temperature, which was better than the commercial YAG:Ce phosphor in terms of their thermal quenching properties. These results indicated that the as-prepared Sr3Gd2(Si3O9)2:Tb^3+,Ce^3+ samples could be used as green emission phosphors for possible applications in near ultraviolet based WLEDs. 展开更多
关键词 Sr3Gd2(Si3O9)2 photoluminescence quantum yields thermal stability LUMINESCENCE rare earths
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SINGLET OXYGEN QUANTUM YIELDS OF PORPHYRIN-BASED PHOTOSENSITIZERS FOR PHOTODYNAMIC THERAPY 被引量:3
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作者 BU-HONG LI LI-SHENG LIN +1 位作者 HUI-YUN LIN SHU-SEN XIE 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2008年第1期141-149,共9页
The major cytotoxic agent with most current photosensitizers used in photodynamic therapy(PDT)is widely believed to be singlet oxygen(^(1)O_(2)).Determination of the ^(1)O_(2) quantum yields for porphyrin-based photos... The major cytotoxic agent with most current photosensitizers used in photodynamic therapy(PDT)is widely believed to be singlet oxygen(^(1)O_(2)).Determination of the ^(1)O_(2) quantum yields for porphyrin-based photosensitizers,including hematoporphyrin derivative(HiPorfin),hematoporphyrin monomethyl ether(HMME)and photocarcinorin(PsD-007)in air-saturated dimethylformamide(DMF)solutions were performed by the direct measurement of their near-infrared luminescence.In addition,^(1)O_(2) quencher sodium azide was employed to confirm the ^(1)O_(2) generation from the investigated photosensitizers.The maximal ^(1)O_(2) luminescence occurs at about 1280 nm with full width at half maximum of 30 nm.The ^(1)O_(2) quantum yields were found to be 0.61±0.03,0.60±0.02 and 0.59±0.03 for HiPorfin,HMME and PsD-007,respectively.These results provide that these porphyrin-based photosensitizers produce ^(1)O_(2) under irradiation,which is of significance for the study of their photodynamic action in PDT. 展开更多
关键词 Photodynamic therapy PORPHYRIN singlet oxygen LUMINESCENCE quantum yield
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Synthesis and Fluorescence Quantum Yield of Gd<sub>1-x</sub>Eu<sub>x</sub>OOH Crystals 被引量:2
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作者 Hiroaki Samata Daisuke Itakura +1 位作者 Shungo Imanaka Tadashi C. Ozawa 《Journal of Materials Science and Chemical Engineering》 2014年第3期23-29,共7页
Eu3+-doped gadolinium oxyhydroxide Gd1-xEuxOOH crystals were synthesized by the flux method. The X-ray diffraction data for the crystals were well refined assuming a monoclinic structure with the P21/m space group. Gd... Eu3+-doped gadolinium oxyhydroxide Gd1-xEuxOOH crystals were synthesized by the flux method. The X-ray diffraction data for the crystals were well refined assuming a monoclinic structure with the P21/m space group. Gd1-xEuxOOH (x ≤ 0.2) crystals showed strong red emission, and the highest fluorescence quantum yield (Φf) was 0.27, obtained for x = 0.10. Φf decreased rapidly as the Eu3+ content x increased above 0.2, owing to concentration quenching. Analysis with a percolation model indicated three-dimensional energy transfer between the Eu3+ ions. 展开更多
关键词 GADOLINIUM Oxyhydroxide Fluorescence quantum yield PERCOLATION Model
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Progressive quantum algorithm for maximum independent set with quantum alternating operator ansatz
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作者 Xiao-Hui Ni Ling-Xiao Li +3 位作者 Yan-Qi Song Zheng-Ping Jin Su-Juan Qin Fei Gao 《Chinese Physics B》 2025年第7期75-87,共13页
The quantum alternating operator ansatz algorithm(QAOA+)is widely used for constrained combinatorial optimization problems(CCOPs)due to its ability to construct feasible solution spaces.In this paper,we propose a prog... The quantum alternating operator ansatz algorithm(QAOA+)is widely used for constrained combinatorial optimization problems(CCOPs)due to its ability to construct feasible solution spaces.In this paper,we propose a progressive quantum algorithm(PQA)to reduce qubit requirements for QAOA+in solving the maximum independent set(MIS)problem.PQA iteratively constructs a subgraph likely to include the MIS solution of the original graph and solves the problem on it to approximate the global solution.Specifically,PQA starts with a small-scale subgraph and progressively expands its graph size utilizing heuristic expansion strategies.After each expansion,PQA solves the MIS problem on the newly generated subgraph using QAOA+.In each run,PQA repeats the expansion and solving process until a predefined stopping condition is reached.Simulation results show that PQA achieves an approximation ratio of 0.95 using only 5.57%(2.17%)of the qubits and 17.59%(6.43%)of the runtime compared with directly solving the original problem with QAOA+on Erd?s-Rényi(3-regular)graphs,highlighting the efficiency and scalability of PQA. 展开更多
关键词 quantum alternating operator ansatz algorithm(QAOA+) constrained combinatorial optimization problems(CCOPs) maximum independent set(MIS) feasible space
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Maximum sustainable yield estimation of enhancement species with the characteristics of movement inside and outside marine ranching
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作者 Yingbin WANG Wei ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第6期2380-2387,共8页
Marine ranching can be regarded as a type of artificial fishery,and its construction aims at the sustainable utilisation of fishery resources.Therefore,the sustainable yield level of target species in marine ranching ... Marine ranching can be regarded as a type of artificial fishery,and its construction aims at the sustainable utilisation of fishery resources.Therefore,the sustainable yield level of target species in marine ranching has become one of the concerns of stakeholders.The enhancement surplus production model proposed by Wang(2021)based on the traditional surplus production model can be used to assess the sustainable utilisation of settled species in marine ranches.However,when the target species has the characteristics of migration inside and outside marine ranches,its sustainability assessment will be aff ected.Based on the movement range and resource density levels of enhancement species inside and outside marine ranches,we built a biomass change model that is suitable for enhancement species with migration characteristics inside and outside marine ranches(migration enhancement biomass model).Moreover,we simulated the effects of factors,such as the ratio of the movement range and the ratio of resource density within and outside marine ranches and the fishing strategy for the enhancement species in marine ranches,on the estimation of maximum sustainable yield(MSY).Results show that the large movement range of enhancement species outside marine ranches was associated with the obvious advantage of the proposed migration enhancement model over the traditional enhancement production model.A small difference in the densities of enhancement species inside and outside marine ranches was highly beneficial for improving the accuracy of MSY estimation.The migration enhancement biomass model proposed in this study provides an idea for estimating the MSY of an enhancement species that migrates inside and outside marine ranches.Researchers can adjust the parameters of the model in accordance with the actual situation of resource distribution and changes to improve the scientificity of fishery stock assessment. 展开更多
关键词 marine ranching stock enhancement and releasing MIGRATION production model maximum sustainable yield(MSY)
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Verification and evaluation of the “Three Optimums Theory”in rice breeding for maximum yield
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作者 YANG Shouern,ZHANG Longbu,CHEN Wenfu,XU Zhengjin,and WANG Jinmin,Shenyang Agri Univ 《Chinese Rice Research Newsletter》 1994年第4期11-11,共1页
Rice breeding for maximum yield is a hot topic today in the rice community of the world, and a hard nut to crack into the bargain. For many years, we have been devoted to the subject. In 1987 we discussed the subject ... Rice breeding for maximum yield is a hot topic today in the rice community of the world, and a hard nut to crack into the bargain. For many years, we have been devoted to the subject. In 1987 we discussed the subject in publications at home and abroad, in which we first introduced the general strategy of combining ideal plant morphology with the use of vigor. Afterward, drawing on the wisdoms of other researchers, we experimented with test materials featuring "rather short stalks" and "rather big panicles", but the results were not very satisfactory. Then, we switched from the "two rathers" to the "three optimums" (plant height, panicle size, and tillering ability). Three years’ (1991-1993) verification, especially the demonstra 展开更多
关键词 in rice breeding for maximum yield Three Optimums theory
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Influence of Gd doping on the absolute quantum efficiency and lifetime of Eu_xGd_(1-x)(TTA)_3 phens 被引量:6
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作者 Ting-Ting Dai Lei Liu +9 位作者 Dong-Liang Tao Shi-Gang Li HongZhang Yu-Min Cui Yong-Zhong Wang Ji-Tang Chen Kun Zhang Wen-Zhong Sun Xiao-Yun Zhao gel Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第6期892-896,共5页
Absolute quantum yield (Ф) is one of the most important parameters to evaluate the potential of novel materials. Lanthanide complexes EuxGd1-x(TTA)3phens are synthesized with the ratio of Gd3+ dopant concentrati... Absolute quantum yield (Ф) is one of the most important parameters to evaluate the potential of novel materials. Lanthanide complexes EuxGd1-x(TTA)3phens are synthesized with the ratio of Gd3+ dopant concentration ranging from 10% to 90% to improve the absolute quantum yield. EuxGd1-x(TTA)3phens possess similar infrared and ultraviolet spectra, showing that they have similar molecular structures. The absolute emission quantum yields of EuxGd1-x(TTA)3phens are determined using a fluoromax-4 spectrofluorometer equipped with an integrating sphere. The fluorescence lifetimes of the EuxGd1-x(TTA)3phens are measured in the same experiment. It was found that both absolute quantum yields and fluorescence lifetimes of EuxGd1-x(TTA)3phens are of quasi-periodic variation with the change of the Gd3. dopant concentrations. The absolute quantum efficiency and fluorescence lifetime vary with respect to the Gd content in an opposite fashion, indicating that the rate of energy absorption by the EuxGd1-x(TTA)3phens and the conversion to light energy is critical for the absolute quantum efficiency. The radiative rate constant Kr and non-radiative rate constant Knr are calculated. The dependence of Kr and Knr on the Gd3+ dopant concentrations is very similar to that of absolute quantum efficiency. The radiation rate constant Kr and absolute quantum efficiency have a linear relationship. 展开更多
关键词 JEuropium complexes Gd doping Absolute quantum yield Fluorescent lifetime
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Structure regulation for ultra-high luminescence quantum yield lanthanide complex and simultaneous detection of cancer marker and ferrous ion 被引量:6
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作者 Min Liu Zhifeng Li +6 位作者 Jianhui Xiong Yefei Jiang Ting Tang Jinkai Qiu Junwei Yao Seik Weng Ng Chenghui Zeng 《Journal of Rare Earths》 SCIE EI CAS CSCD 2021年第10期1194-1203,I0002,共11页
The exploitation of a highly selective and sensitive probe to detect both cancer marker and metal ion is of great importance.In this work,the "one stone two bird" agent of 1,10-phenanthroline(phen) is design... The exploitation of a highly selective and sensitive probe to detect both cancer marker and metal ion is of great importance.In this work,the "one stone two bird" agent of 1,10-phenanthroline(phen) is designed to disrupt the polymeric lanthanide MOFs(LnMOFs,[Ln(CHO_(2))_(3)]n,Ln=Tb,la;Eu,1 b,CHO_(2)=formic acid) {[Ln(CHO_(2))_(4)·(C_(2) H_(8) N)]n,Ln=Y,2 a;Gd,2 b;Dy,2 c,C_(2)H_(8) N=dimethylamine}) into a soluble mononuclear species [Ln(phen)_(2)(NO_(3))_(3),Ln=Tb,3 a;Eu,3 b] as well as to provide an antenna for efficient photons absorption,resulting in an ultra-high luminescence quantum yield(QY,90%) europium complex.The luminescence QY is among the highest record of monomeric(zero-dimensional) lanthanide complexes.Furthermore,mononuclear Tb3+complex(3 a) functions as a multiplex sensor towards both Fe^(2+)and cancer marker of 5-hydroxyindole-3-acetic acid(5-HIAA).Importantly,the limit of detection(LOD)for sensing 5-HIAA is an ultra-sensitive value of 1 × 10 s mol/L,which is even lower than that necessary for the early diagnosis of carcinoid tumors.More interestingly,sensing results in simulated urine reveals that 3 a has potential application for early diagnosis in the clinic. 展开更多
关键词 Ultra-high luminescence quantum yield Lanthanide complex Simultaneous detection Cancer marker Ferrous ion Rare earths
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Barium charge transferred doped carbon dots with ultra-high quantum yield photoluminescence of 99.6% and applications 被引量:3
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作者 Yao Liu Jianfei Wei +3 位作者 Xiang Yan Ming Zhao Chaozhong Guo Quan Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第2期861-865,共5页
Long-emission carbon dots(CDs) is triggering immense enthusiasm on account of their intrinsic merits of high chemical stability and excellent optical properties.In this study,a facile and rapid approach was developed ... Long-emission carbon dots(CDs) is triggering immense enthusiasm on account of their intrinsic merits of high chemical stability and excellent optical properties.In this study,a facile and rapid approach was developed for the preparation of barium-doped carbon dots(Ba-CDs) with yellow fluo rescence emission and high quantum yields.Surface chemistry and the chemical architecture of the Ba-CDs was revealed under various spectroscopic methods.This work provides more insights into the effects of charge transfer caused by Ba heteroatoms,which is considered as the most challenging step in the investigation on luminescence mechanism.Remarkably,the prepared Ba-CDs were successfully applied as fluorescent probes in the detection of trace water in organic solvents(ethanol,isopropanol,acetone,tetrahydrofuran).Comparing with traditional fluorescent probes for water detection in organic solvents,Ba-CDs detection provides a more sensitive,much faster and more economical approach. 展开更多
关键词 Ba-doped Carbon dots quantum yield Charge transfer Fluorescent sensors
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Europium Coordination Compound with Highly Improved Luminescent Quantum Yield 被引量:2
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作者 李鑫 李晨媛 +3 位作者 郑维维 杨丹 熊克才 盖艳丽 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第2期306-311,共6页
The luminescent properties of two Eu3+ compounds based on quinoline-2-car- boxylic acid (Hqc), [Na2Eu2(qc)6(CH3COO)2(H2O)4].2DMF (1) and [Eu2(qc)6(H2O)6].3H2O (2), as well as their syntheses and struc... The luminescent properties of two Eu3+ compounds based on quinoline-2-car- boxylic acid (Hqc), [Na2Eu2(qc)6(CH3COO)2(H2O)4].2DMF (1) and [Eu2(qc)6(H2O)6].3H2O (2), as well as their syntheses and structures are reported. Both compounds are formed by slow evaporation at room temperature and exhibit zero dimensional dinuclear structures. It is worth mentioning that a 4.5-fold enhancement in luminescent quantum yield is achieved by reducing the nonradiative deactivation, through which the quantum yield increases remarkably to 67.62% for 1 compared with 12.18% for 2. 展开更多
关键词 Eu3+ compound coordination environment luminescent quantum yield
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Quantum Generalized Measurement and Deterministic Generation of Maximum Entangled Pure State 被引量:1
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作者 ZHANG Ming DAI Hong-Yi +1 位作者 HU De-Wen XIE Hong-Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期833-837,共5页
We propose the concept of the quantum generalized projector measurement (QGPM) for finite-dimensional quantum systems by studying the quantum generalized measurement. This research reveals a distinguished property o... We propose the concept of the quantum generalized projector measurement (QGPM) for finite-dimensional quantum systems by studying the quantum generalized measurement. This research reveals a distinguished property of this quantum generalized measurement: no matter what the system state is prior to the measurement and what the result of the measurement occurs, the state of the system after the measurement can be collapsed into any specified pure state, i.e., the state of quantum system can be deterministically reduced to any specified pure state just by a single QGPM. Subsequently. QGPM can be used to deterministically generate the maximum entangled pure state for quantum systems. We give three concrete theoretic schemes of generating the maximum quantum entangled pure states for two 2-Jevel particles, three 2-level particles and two 3-Jevel particles, respectively. 展开更多
关键词 quantum generalized measurement maximum entanglement state
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Impact parameter dependence of the yield ratios of light particles as a probe of neutron skin 被引量:5
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作者 Ting-Zhi Yan Shan Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第3期59-64,共6页
The yield ratios of neutron/proton(R(n/p)) and ~3H=~3He(R(t/~3He)) with reduced rapidity from 0 to 0.5 are investigated for 50 MeV/u ^(42;44;46;48;50;52;54;56)Ca+^(40)Ca.This was conducted at whole reduced impact para... The yield ratios of neutron/proton(R(n/p)) and ~3H=~3He(R(t/~3He)) with reduced rapidity from 0 to 0.5 are investigated for 50 MeV/u ^(42;44;46;48;50;52;54;56)Ca+^(40)Ca.This was conducted at whole reduced impact parameters using the isospin-dependent quantum-molecular-dynamics model in which the initial neutron and proton densities are sampled within the Skyrme–Hartree–Fock model, using which the neutron skin thickness(△R_(np)) is determined for different neutron-rich Ca isotopes. The results show that both R(n/p) and R(t/~3He) have strong linear correlations with △R_(np) of different Ca isotopic projectiles from five different centralities. It is suggested that R(n/p) and R(t/~3He), from the same centrality, could be treated as possible experimental observables to extract the neutron skin or halo thickness for neutron-rich isotopic nuclei,including the nuclei near the neutron drip line. 展开更多
关键词 yield RATIO NEUTRON SKIN thickness Isospindependent quantum-molecular-dynamics
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The Effective Chiral Model of Quantum Hadrodynamics Applied to Nuclear Matter and Neutron Stars 被引量:1
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作者 Hiroshi Uechi 《Journal of Applied Mathematics and Physics》 2015年第2期114-123,共10页
We review theoretical relations between macroscopic properties of neutron stars and microscopic quantities of nuclear matter, such as consistency of hadronic nuclear models and observed masses of neutron stars. The re... We review theoretical relations between macroscopic properties of neutron stars and microscopic quantities of nuclear matter, such as consistency of hadronic nuclear models and observed masses of neutron stars. The relativistic hadronic field theory, quantum hadrodynamics (QHD), and mean-field approximations of the theory are applied to saturation properties of symmetric nuclear and neutron matter. The equivalence between mean-field approximations and Hartree approximation is emphasized in terms of renormalized effective masses and effective coupling constants of hadrons. This is important to prove that the direct application of mean-field (Hartree) approximation to nuclear and neutron matter is inadequate to examine physical observables. The equations of state (EOS), binding energies of nuclear matter, self-consistency of nuclear matter, are reviewed, and the result of chiral Hartree-Fock ?approximation is shown. Neutron stars and history of nuclear astrophysics, nuclear model and nuclear matter, possibility of hadron and hadron-quark neutron stars are briefly reviewed. The hadronic models are very useful and practical for understanding astrophysical phenomena, nuclear matter and radiation phenomena of nuclei. 展开更多
关键词 A Relativistic Field theORY of Nuclei: quantum Hadrodynamics (QHD) the Equivalence of MEAN-FIELD Approximations and HARTREE Approximation Density Functional theORY (DFT) maximum MASSES of Neutron Stars
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Maximum confidence measurements via probabilistic quantum cloning
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作者 张文海 余龙宝 +1 位作者 曹卓良 叶柳 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期169-172,共4页
Probabilistic quantum cloning(PQC) cannot copy a set of linearly dependent quantum states.In this paper,we show that if incorrect copies are allowed to be produced,linearly dependent quantum states may also be clone... Probabilistic quantum cloning(PQC) cannot copy a set of linearly dependent quantum states.In this paper,we show that if incorrect copies are allowed to be produced,linearly dependent quantum states may also be cloned by the PQC.By exploiting this kind of PQC to clone a special set of three linearly dependent quantum states,we derive the upper bound of the maximum confidence measure of a set.An explicit transformation of the maximum confidence measure is presented. 展开更多
关键词 probabilistic quantum cloning quantum state discrimination maximum confidence measurement
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Fluorescence quantum yield of Gd_(0.9-x)R_xEu_(0.1)OOH(R=Y, La) crystals
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作者 Hiroaki Samata Katsutoshi Kobayashi +1 位作者 Masashi Hanioka Tadashi C.Ozawa 《Journal of Rare Earths》 SCIE EI CAS CSCD 2015年第12期1256-1260,共5页
Gdo.9xRxEUo.lOOH (R=Y, La) crystals were synthesized by a flux method using a mixture of NaOH and KOH as the flux. X-ray diffraction data were well refined using the Rietveld method assuming that the crystals had a ... Gdo.9xRxEUo.lOOH (R=Y, La) crystals were synthesized by a flux method using a mixture of NaOH and KOH as the flux. X-ray diffraction data were well refined using the Rietveld method assuming that the crystals had a monoclinic structre belonging to the P21/m space group. The unit cell volumes of the Gdo.9 xLaxEuo.OOH crystals increased with increasing x, whereas those of Gdo.9-xYxEUo.lOOH decreased with increasing x. The Commission Internationale de IEclairage (CIE) chromaticity coordinates of Gdo.9 xRxEUo.lOOH (R=Y, La) crystals were located in the red region and were nearly constant over the range ofx values considered. The fluorescence quantum yield Dr monotonically decreased with increasing x regardless of the ionic radii of the substitute ions. The fact that the Dr value of Lao.9EuoAOOH was greater than that of Gdo.gEUo.lOOH indicated that the observed decrease in the values of the Gdo.9-,LaxEuo.1OOH crystals up to x=0.3 could not be attributed to an increase in the distance between Eu3+ ions or to a decrease in the Gd3+ content. The decrease might be due to an increase of killer centers introduced by elemental substitutions with the larger ion. 展开更多
关键词 rare-earth oxyhydroxide PHOSPHOR elemental substitution fluorescence quantum yield
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Fluorescent Quantum Yield of Pyrene Probe in Ultrathin Polymer Films
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作者 Wan-chu Wei Shuo Feng +2 位作者 Cai-xia Zheng Guo-dong Liang 祝方明 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2017年第3期400-406,共7页
The fluorescently labelled polymers including pyrene-labelled polystyrene(PyPS) and pyrene-labelled poly(methyl methacrylate)(PyPMMA) with narrow molecular weight distributions were synthesized by the atom transfer ra... The fluorescently labelled polymers including pyrene-labelled polystyrene(PyPS) and pyrene-labelled poly(methyl methacrylate)(PyPMMA) with narrow molecular weight distributions were synthesized by the atom transfer radical copolymerization(ATRCP) of styrene or methyl methacrylate with 1-pyrenemethyl methacrylate(PyMMA). The ultrathin PyPS and PyPMMA films with the thickness ranging from 30 nm to 400 nm supported on the quartz slides were prepared by spin-coating. The fluorescent quantum yield(QY) of the pyrene probe in the ultrathin polymer films was investigated by the photoluminescence spectrometer using an integrating sphere detector. The QY decreased with the reduction of film thickness in the sub-200 nm range. 展开更多
关键词 Pyrene-labelled polystyrene Pyrene-labelled poly(methyl methacrylate) Ultrathin polymer films Fluorescent quantum yield
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Effects of interface roughness on photoluminescence full width at half maximum in GaN/AlGaN quantum wells
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作者 王维颖 刘贵鹏 +5 位作者 金鹏 毛德丰 李维 王占国 田武 陈长清 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期562-565,共4页
Low temperature photoluminescence (PL) measurements have been performed for a set of GaN/AlxGal xN quantum wells (QWs). The experimental results show that the optical full width at half maximum (FWHM) increases ... Low temperature photoluminescence (PL) measurements have been performed for a set of GaN/AlxGal xN quantum wells (QWs). The experimental results show that the optical full width at half maximum (FWHM) increases relatively rapidly with increasing A1 composition in the AlxGal xN barrier, and increases only slightly with increasing GaN well width. A model considering the interface roughness is used to interpret the experimental results. In the model, the FWHM's broadening caused by the interface roughness is calculated based on the triangle potential well approximation. We find that the calculated results accord with the experimental results well. 展开更多
关键词 GaN/A1GaN quantum wells interface roughness optical full width at half maximum
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Maximum Momentum,Minimal Length and Quantum Gravity Effects of Compact Star Cores
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作者 张修明 付伟 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期14-18,共5页
Based on the generalized uncertainty principle with maximum momentum arid minimal length, we discuss the equation of state of ideal ultra-relativistic Fermi gases at zero temperature. Maximum momentum avoids the probl... Based on the generalized uncertainty principle with maximum momentum arid minimal length, we discuss the equation of state of ideal ultra-relativistic Fermi gases at zero temperature. Maximum momentum avoids the problem that the Fermi degenerate pressure blows up since the increase of the Fermi energy is not limited. Applying this equation of state to the Tolman-Oppenheimer Volkoff (TOV) equation, the quantum gravitational effects on the cores of compact stars are discussed. In the center of compact stars, we obtain the singularity-free solution of the metric component, gtt ~-(1 + 0.2185×r^2). By numerically solving the TOV equation, we find that quantum gravity plays an important role in the region r~10^4α0(△x)min. Current observed masses of neutron stars indicate that the dimensionless parameter α0 cannot exceed 10^19. 展开更多
关键词 of on it maximum Momentum Minimal Length and quantum Gravity Effects of Compact Star Cores in that is
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Dependence of Quantum Yields on Size of Ag Nano-particle Embedded in BaO Thin Film
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作者 CAIWu-de YANGYi-bing 《Semiconductor Photonics and Technology》 CAS 2002年第1期27-31,共5页
Theoretical dependence of the quantum yields on the size of Agnano-particle distribution from 0.8 nm to 37 nm embedded in BaOsemiconductor is discussed. The calculation results show that theincrease in Ag nano-particl... Theoretical dependence of the quantum yields on the size of Agnano-particle distribution from 0.8 nm to 37 nm embedded in BaOsemiconductor is discussed. The calculation results show that theincrease in Ag nano-particle diameter leads to the increase of thequantum yield threshold and the emergence of the rough Gaussian form,the results also shown that the greater increase in Ag nano-particlediameter causes the emergence of the exact Gaussian form and makesthe peaks rise up. 展开更多
关键词 quantum yield ag nano-prticles ultrafast nonlinear response
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