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Chinese Journal of Chemical Physics 2014年第3期27卷 259-264页

作者： yu-jin Zhang yu-zhi song Chuan-kui Wang College of Physics and Electronics Shandong Normal University Jinan 250014 China

By numerically solving the Maxwell-Bloch equations using an iterative predictor-corrector finite-difference time-domain technique, we investigate propagating properties of a few-cycle laser pulse in a 4,4＇-bis（di-n-butylamino） stilbene （BDBAS） molecular medium when a static electric field exists. Dynamical two-photon absorption （TPA） cross sections are obtained and optical limiting （OL） behavior is displayed. The results show that when the static electric field intensity increases, the dynamical TPA cross section is enhanced and the OL behavior is improved. Moreover, both even- and odd-order harmonic spectral components are generated with existence of the static electric field because it breaks the inversion symmetry of the BDBAS molecule. This work provides a method to modulate the nonlinear optical properties of the BDBAS compounds.

关键词： Static electric field Optical limiting Two-photon absorption Organic molecule

Phase State as a Limiting Case of SU(1,1) Coherent State

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Communications in Theoretical Physics 2009年第1期51卷 68-70页

作者： yu zhi-song FAN Hong-Yi Department of Physics Hubei Normal University Huangshi 435002 China Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China

We show that the Susskind-Glogower phase state is a limiting case of a kind of SU（1,1） coherent states. By analogy, based on the bipartite entangled state representation （ESR） we demonstrate that an appropriate SU（1,1） coherent state composed of the two-mode unitary phase operator e^i also leads to a new phase state in two-mode Fock space, e^i is diagonalized in the ESR.

关键词： phase state unitary phase operator bipartite entangled state representation SU(1 1) coherentstate

Solvent Effects on Two-Photon Absorption of Alkyne and Alkene π-bridging Chromophores

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Chinese Journal of Chemical Physics 2017年第1期30卷 63-70,I0001页

作者： Jing Li Chuan-kui Wang yu-zhi song College of Physics and Engineering Qufu Normal University Qufu 273165 China School of Physics and Electronics 5handong Normal University ginan 250014 China

The present work concerns the study of solvent effects on the geometrical structures, as well as one- and two-photon absorption （TPA） processes, for two series of alkyne and alkene π-bridging molecules, within the framework of the polarization continuum model. Particular emphasis was put on the characterization of solvent effects on the molecular geometrical structures and geometric distortion, which were measured by the bond-length-alternation parameter. The π centres in the compounds are seen to play a decisive role in increasing the TPA cross section and nonlinear optical properties. All studied molecules have relatively strong TPA characteristics, while the alkyne π-bridging ones yield larger TPA cross sections.

关键词： Nonlinear optics Two photon absorption Solvent effect Charge transfer Bond length alternation

Theoretical Analysis on Optical Limiting Properties of Newly Synthesized Graphene Oxide-Porphyrin Composites

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Chinese Journal of Chemical Physics 2015年第3期28卷 257-262,I0001页

作者： yu-jin Zhang Wen-jing Yang Jian-zhong Fan yu-zhi song Chuan-kui Wang College of Physics and Electronics Shandong Normal University Jinan 250014 China

Optical limiting （OL） properties and two-photon absorption （TPA） of a series of covalently linked graphene oxide-porphyrin composite materials have been investigated by numerically solving the rate equations and field intensity equation with an iterative predictor-corrector finite-difference time-domain technique in nanosecond time domain. Our results show that graphene oxide-porphyrin composites exhibit enhanced OL behavior and possess larger TPA cross section compared with individual porphyrins. Interestingly~ unlike the previous result that porphyrin with heavier central metal shows better nonlinear abilities than that with- out metal substitute, graphene oxide-metal free porphyrin composite has stronger nonlinear absorption properties compared with graphene oxide-metal porphyrin composite. The com- putational results are in reasonable agreement with the experimental ones. Special attention has been paid to the influence of thickness of the medium and pulse width on TPA cross sections, which presents that larger TPA cross sections are obtained as the medium is thicker or the pulse duration is wider.

关键词： Optical limiting Two-photon absorption Graphene oxide Porphyrin

Field-free molecular orientation steered by combination of super-Gaussian and THz half-cycle laser pulses

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Chinese Physics B 2019年第11期28卷 150-155页

作者： Qi-yuan Cheng yu-zhi song Qing-Tian Meng Medical Engineering Department Shandong Provincial Hospital Affiliated to Shandong UniversityJinan 250021China School of Physics and Electronics Shandong Normal UniversityJinan 250358China

The molecular orientation created by laser fields is important for steering chemical reactions. In this paper, we propose a theoretical scheme to manipulate field-free molecular orientation by using an intense super-Gaussian laser pulse and a time-delayed terahertz half-cycle pulse(THz HCP). It is shown that the degree of field-free orientation can be doubled by the combined pulse with respect to the super-Gaussian pulse or THz HCP alone. Moreover, different laser intensities, carrier envelop phases, shape parameters, and time delays have great influence on the positive and negative orientations, with other conditions unchanged. Furthermore, it is indicated that the maximum degree and direction of molecular orientation can be precisely controlled by half of the duration of the super-Gaussian pulse. Finally, by adjusting the laser parameters of the super-Gaussian laser pulse and THz HCP, the optimal results of negative orientation and corresponding rotational populations are obtained at different temperatures of the molecular system.

关键词： molecular orientation terahertz half-cycle pulse super-Gaussian pulse

Decolorization of azo dyes with high salt concentration by salt-tolerant mixed cultures under anaerobic conditions

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Journal of Environmental Sciences 2005年第6期17卷 984-988页

作者： GUO Jian-bo ZHOU Ji-ti WANG Dong WANG Jing yu Hui song zhi-yong School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116023 China

Because the lack of detailed study of biological decolorization in high salt dye wastewater, it is still difficult to evaluate the biological treatment on high-salinity dye wastewater. The experiments were carried out to study the salt-tolerant bacteria, which is useful in the treatment of high-salinity colored wastewater. Simulated wastewater containing 5-150 g/L salt （NaCI） and 50-2000 mg/L Reactive Brilliant Red K-2BP was treated with three salt-tolerant mixed cultures （CAS, TAS, DSAS）, which were under a gradually acclimated procedure. With the increase of concentrations of salt and dye, the decolorization became low. The abilities of decolorization of dyes wastewater by three mixed cultures （CAS, TAS, DSAS） were studied, CAS and DSAS mixed cultures showed more active for the treatment of high-salinity colored wastewater than TAS mixed cultures. The results suggested that there might be a simple process for the high salt wastewater treatment, which could be incorporated into conventional activated sludge plants.

关键词： anaerobic decolorization hyper-salinity salt-tolerant mixed cultures

Dynamics of molecular alignment steered by a few-cycle terahertz laser pulse

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Chinese Physics B 2022年第10期31卷 377-383页

作者： Qi-yuan Cheng yu-zhi song Deng-Wang Li zhi-Ping Liu Qing-Tian Meng Medical Engineering Department Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021China School of Physics and Electronics Shandong Normal UniversityJinan 250358China Shandong Laibo Biotechnology Co. Ltd.Jinan 250101China School of Control Science and Engineering Shandong UniversityJinan 250061China

The field-free alignment of molecule Cl CN is investigated by using a terahertz few-cycle pulse(THz FCP)based on the time-dependent density matrix *** is shown that a high degree of molecular alignment can be obtained by changing the matching number of the THz FCPs in the adiabatic regime and the non-adiabatic *** matching number can affect both the maximum value of the alignment and the time at which it is *** is also found that a higher degree of alignment can be achieved by using the THz FCP at lower intensity and there exists an optimal threshold of molecular alignment with the increase of the field *** found is the frequency sensitive region in which the degree of maximum alignment can be enhanced greatly by modulating the center frequencies of different THz *** investigation demonstrates that comparing with a THz single-cycle pulse,a better result of the field-free alignment can be created by a THz FCP at a constant rotational temperature of molecule.

关键词： molecular alignment few-cycle terahertz pulse density matrix theory

Mucosa-associated lymphoid tissue lymphoma of the trachea treated with radiotherapy:A case report

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World Journal of Clinical Cases 2023年第7期11卷 1607-1614页

作者： Chan-Jun Zhen Ping Zhang Wen-Wen Bai yu-zhi song Jun-Li Liang Xue-Ying Qiao zhi-Guo Zhou Department of Radiation Oncology The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hebei ProvinceChina Nursing Department The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hebei ProvinceChina

BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma originates in the marginal zone of lymphoid *** is one of the most frequent non-gastrointestinal organs involved,here known as bronchus-associated lymphoid tissue(BALT)*** lymphoma of unknown etiology,and most patients are *** treatment of BALT lymphoma is *** SUMMARY A 55-year-old man admitted to hospital had a three-month history of progressively coughing up yellow sputum,chest stuffiness,and shortness of *** bronchoscopy revealed mucosal visible beaded bumps 4 cm from the tracheal carina at 9 o'clock and 3 o'clock,the right main bronchus,and the right upper lobe *** specimens showed MALT *** tomography virtual bronchoscopy(CTVB)showed uneven main bronchial wall thickening and multiple nodular *** lymphoma stage IE was diagnosed after a staging *** treated the patient with radiotherapy(RT)alone.A total dose of 30.6 Gy/17 f/25 d was *** patient had no obvious adverse reactions during *** CTVB was repeated after RT and showed that the right side of the trachea was slightly *** was repeated 1.5 mo after RT and again showed that the right side of the trachea was slightly *** CTVB showed no signs of *** patient now has no *** BALT lymphoma is an uncommon disease and shows good *** treatment of BALT lymphoma is *** recent years,less invasive diagnostic and therapeutic approaches have been *** was effective and safe in our *** use of CTVB could provide a noninvasive,repeatable,and accurate method in diagnosis and follow-up.

关键词： Mucosa-associated lymphoid tissue lymphoma Computed tomography virtual bronchoscopy Radiotherapy Prognosis Case Report

Review of gallium oxide based field-effect transistors and Schottky barrier diodes

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Chinese Physics B 2019年第1期28卷 65-81页

作者： Zeng Liu Pei-Gang Li yu-song zhi Xiao-Long Wang Xu-Long Chu Wei-Hua Tang Laboratory of Information Functional Materials and Devices School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China China Aerospace Academy of Systems Science and Engineering Beijing 100048China

Gallium oxide(Ga_2O_3), a typical ultra wide bandgap semiconductor, with a bandgap of ~4.9 e V, critical breakdown field of 8 MV/cm, and Baliga's figure of merit of 3444, is promising to be used in high-power and high-voltage ***, a keen interest in employing Ga_2O_3 in power devices has been aroused. Many researches have verified that Ga_2O_3 is an ideal candidate for fabricating power devices. In this review, we summarized the recent progress of field-effect transistors(FETs) and Schottky barrier diodes(SBDs) based on Ga_2O_3, which may provide a guideline for Ga_2O_3 to be preferably used in power devices fabrication.

关键词： gallium oxide(Ga2O3) field-effect transistors(FETs) Schottky barrier diodes(SBDs)

Synthesis of free-standing Ga_2O_3 films for flexible devices by water etching of Sr_3Al_2O_6 sacrificial layers

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Chinese Physics B 2019年第1期28卷 166-170页

作者： Xia Wang Zhen-Ping Wu Wei Cui yu-song zhi zhi-Peng Li Pei-Gang Li Dao-You Guo Wei-Hua Tang Laboratory of Information Functional Materials and Devices School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100876China Center for Optoelectronics Materials and Devices Department of PhysicsZhejiang Sci-Tech UniversityHangzhou 310018China

Flexible electronic devices have attracted much attention due to their practical and commercial value. Integration of thin films with soft substrate is an effective way to fabricate flexible electronic devices. Ga_2O_3 thin films deposited directly on soft substrates would be amorphous mostly. However, the thickness of the thin film obtained by mechanical exfoliation method is difficult to control and the edge of the film is fragile and easy to be damaged. In this work, we fabricated free-standing Ga_2O_3 thin films using the water-soluble perovskite Sr_3Al_2O_6 as a sacrificial buffer layer. The obtained Ga_2O_3 thin films were polycrystalline. The thickness and dimension of the films were controllable. A flexible Ga_2O_3solar-blind UV photodetector was fabricated by transferring the free-standing Ga_2O_3 film on a flexible polyethylene terephthalate substrate. The results displayed that the photoelectric performances of the flexible Ga_2O_3 photodetector were not sensitive to bending of the device. The free-standing Ga_2O_3 thin films synthesized through the method described here can be transferred to any substrates or integrated with other thin films to fabricate electronic devices.

关键词： free-standing Ga2O3 thin film crystalline Sr3Al2O6 flexible photodetector