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Photoelectron momentum distributions of single-photon ionization under a pair of elliptically polarized attosecond laser pulses

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Chinese Physics B 2020年第7期29卷 313-320页

作者： Hui-Fang Cui Xiang-yang miao College of Physics and Information Engineering Shanxi Normal UniversityLinfen 041004China Key Laboratory of Spectral Measurement and Analysis of Shanxi Province Shanxi Normal UniversityLinfen 041004China

The attosecond ionization dynamics of atoms has attracted extensive attention in these ***,the role of the initial state is not clearly *** address this question,we perform simulations on the neon atom and its model atom with different initial states by numerically solving the corresponding two-dimensional time-dependent Schrodinger¨*** theoretically investigate atomic photoelectron momentum distributions(PMDs)by a pair of elliptically polarized attosecond laser *** find that the PMD is sensitive not only to the ellipticities of the pulses,the relative helicity,and time delay of the pulses,but also to the symmetry of the initial electronic *** are analyzed by the first-order time-dependent perturbation theory(TDPT)and offer a new tool for detecting the rotation direction of the ring currents.

关键词： photoelectron momentum distributions elliptically polarized attosecond laser pulses magnetic quantum numbers rotation direction of the ring currents

Nonlinear Acoustic-Optical Effect and Extraordinary Diffraction Distribution in Liquid Surface

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Chinese Physics Letters 2013年第12期30卷 67-70页

作者： miao yang WANG Shao-Ping School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191

Nonlinear acoustic-optical effect is discovered by using a low-frequency liquid surface acoustic wave with great *** are higher harmonics in diffracted light and the intensity of the higher harmonic has the relation of Bessel's function with the *** light patterns diffracted by the wave can be classified into the ordinary and extraordinary beams which are corresponding to small and great amplitudes of the *** ordinary and extraordinary patterns are observed experimentally and the critical amplitude value is found.

关键词： ordinary Nonlinear wave

Metastable state of gas hydrate during decomposition: A novel phenomenon

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Chinese Journal of Chemical Engineering 2020年第4期28卷 949-954页

作者： Ronghui Sun Zhen Fan Lei yang Yuanping Li Xin Lü yang miao Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of TechnologyDalian 116023China School of Chemistry University of GlasgowGlasgow G128QQUnited Kingdom 3 Institute of Science and TechnologyShenzhen BranchChina National Offshore Oil CorporationGuangzhou 510420China CNOOC Research Institute Co.Ltd Beijing 100028China Xingang Shipbuilding Heavy Industry Co. Ltd.Tianjin 300452China

Natural gas hydrates are solid compounds with cage-like structures formed by gas and *** intriguing phenomenon that gas hydrates can dissociate at a low rate below the ice freezing point has been viewed as the metastability of *** mechanisms of hydrate metastability have been widely studied,and many mechanisms were proposed involving the self-preservation effect,supercooled water-gas-hydrate metastable equilibrium,and supersaturated liquid-gas-hydrate system *** metastable state of hydrate could be of crucial significance in the kinetics of hydrate formation and decomposition,heat and mass transfer during gas production processes,and the application of hydrate-based technique involving desalination,energy storage and transportation,and gas separation and *** researches have systematically considered this phenomenon,and its mechanism remains *** this work,various mechanisms and hypothesis explaining the metastable state of gas hydrates were introduced and *** studies are still required to reveal the intrinsic nature of this metastable state of gas hydrate,and this work could give some implications on the existing theory and current status of relevant efforts.

关键词： Hydrates Dissociation Metastability Self-preservation Supersaturation

Decoding the electron dynamics in high-order harmonic generation from asymmetric molecular ions in elliptically polarized laser fields

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Chinese Physics B 2022年第4期31卷 287-292页

作者： Cai-Ping Zhang Xiang-yang miao College of Physics and Information Engineering Shanxi Normal UniversityTaiyuan 030031China Key Laboratory of Spectral Measurement and Analysis of Shanxi Province Shanxi Normal UniversityTaiyuan 030031China

The high-order harmonic generation from an asymmetric molecular ion is theoretically investigated based on the Born-Oppenheimer model with two-dimensional electron *** is shown that the harmonic intensity changes periodically in elliptically polarized laser *** periodical character is *** establishing the physical image,the periodicity of the harmonic intensity can be ascribed to the contributions of the ground state and the excited ***,the electron dynamics from different electronic states can be selected via combining the elliptically polarized laser field with a static electric *** harmonics dominated either by ground state or excited state are emitted once in an optical cycle in the combined laser field.

关键词： asymmetric molecular ion high-order harmonic generation electron dynamics elliptically polarized laser field

Structural Characterization of AlMgB_(14) Prepared by Field-activated, Pressure-assisted Synthesis

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Journal of Materials Science & Technology 2013年第1期29卷 77-81页

作者： Wen Liu yang miao Qingsen Meng Shaoping Chen College of Materials Science and Engineering Taiyuan University of Technology School of Chemical and Biological Engineering Taiyuan University of Science and Technology

Mechanical alloying （MA） and field-activated, pressure-assisted synthesis （FAPAS） were used for the in situ synthesis and densification of ultra-hard, super-abrasive AIMgB14 metallic ceramic, performed at 1500 ℃ under a pressure of 60 MPa with the elemental constituents of aluminum, magnesium, and boron. The microstructure and components of synthesized metallic ceramic were observed and determined by scanning electron microscopy （SEM）, energy dispersive X-ray analysis （EDX）, X-ray diffraction （XRD）, and transmission electron microscopy （TEM）. The results showed that the main components of the samples were AIMgB14 with a few ***204 was derived from the contamination of the preliminary powders and the milling process. The average hardness of the samples that provided the results was 26.1 GPa. The average density of the samples was 2.62 g/cm^3, which is 98% of its theoretical density. The sample of AIMgB14-TiB2 composite with 30 wt% TiB2 had a hardness of 29.5 GPa, which is consistent with that of AIMgB14-TiB2 composite with 30 wt% TiB2 prepared by mechanical alloying/hot uniaxial pressing. Thus, a new approach was developed using the mechanical alloying and FAPAS process to synthesize AIMgB14 with fast heating, high efficiency, energy saving, and high yield.

关键词： Field-activated and Pressure-assisted synthesis (FAPAS) AIMgB14 Borides Microstructure

Radiotherapy targeting cancer stem cells “awakens” them to induce tumour relapse and metastasis in oral cancer

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International Journal of Oral Science 2020年第2期12卷 102-113页

作者： yangfan Liu miao yang Jingjing Luo Hongmei Zhou State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases&Department of Oral Medicine West China Hospital of StomatologySichuan UniversityChengduChina State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases&Department of Preventive Dentistry West China Hospital of StomatologySichuan UniversityChengduChina

Radiotherapy is one of the most common treatments for oral cancer. However, in the clinic, recurrence and metastasis of oral cancer occur after radiotherapy, and the underlying mechanism remains unclear. Cancer stem cells(CSCs), considered the "seeds"of cancer, have been confirmed to be in a quiescent state in most established tumours, with their innate radioresistance helping them survive more easily when exposed to radiation than differentiated cancer cells. There is increasing evidence that CSCs play an important role in recurrence and metastasis post-radiotherapy in many cancers. However, little is known about how oral CSCs cause tumour recurrence and metastasis post-radiotherapy. In this review article, we will first summarise methods for the identification of oral CSCs and then focus on the characteristics of a CSC subpopulation induced by radiation, hereafter referred to as "awakened"CSCs, to highlight their response to radiotherapy and potential role in tumour recurrence and metastasis post-radiotherapy as well as potential therapeutics targeting CSCs. In addition, we explore potential therapeutic strategies targeting these "awakened" CSCs to solve the serious clinical challenges of recurrence and metastasis in oral cancer after radiotherapy.

关键词： metastasis tumour hereafter

Synthesis and Structure Description of a New Tetradecaborate [H_3N(CH_2)_2NH_3]_2[B_(14)O_(20)(OH)_6]

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Chemical Research in Chinese Universities 2010年第3期26卷 335-338页

作者： yang miao ZHANG Zheng DING Hong LI Ji-yang State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 P. R. China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 P R. China

A new tetradecaborate, [H3N（CH2）2NH3]2[B14O20（OH）6]（1）, was synthesized by a boric acid ＇flux＇ method, and characterized by X-ray powder diffraction, ICP, IR, TGA and DTA analyses. Single-crystal X-ray diffraction analysis showed that it crystallized in the monoclinic space group P1（No.2） with a=0.85092（10） nm, b=0.88678（11） nm, c=1.00724（13） nm, α=95.099（2）°, β=96.950（2）°, γ=116.845（2）°, V=0.66425（14） nm^3, Z=2, R1=0.0625[1〉2σ（I）], and WRE=0.1172（all data）. The molecule structure of compound 1 comprises the isolated polyanion clusters [B14O20（OH）6]^4- and diprotonated ethylenediamine molecules. Each polyanion cluster contains an 8-ring enclosed by six B3O3 3-ring units. Adjacent clusters are further connected with each other through strong hydrogen-bonding interactions of N（O）-H…O to form a three dimensional（3D） supramolecular structure with 2D pseudo channels along the [010] and [001] directions. The diprotonated ethylenediamine molecules located in the channels interact with the host through extensive hydrogen-bonds. Compound 1 presents few example containing isolated polyborate anions synthesized by a boric acid ＇flux＇ method.

关键词： Polyborate anion Crystal structure Boric acid "flux" method

Preparation and scratch test of AlMgB_(14) modified by TiB_2

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Rare Metals 2015年第2期34卷 101-106页

作者： Lei Zhuang yang miao Wen Liu Qing-Sen Meng College of Materials Science and Engineering Taiyuan University of Technology College of Mechanical and Electrical Engineering Qingdao Binhai University Institute of Chemical and Biological Technology Taiyuan University of Science and Technology

In this paper, the Al Mg B14 and Al Mg B14–Ti B2 composites were synthesized by means of mechanical alloying and the field-activated and pressure-assisted synthesis process. The effect of temperature and pressure on the purity and property of products was discussed. The results show that the process of preparing Al Mg B14 bulk materials is optimized as follows： synthesis temperature1,400–1,500 ℃, heating rate 100 ℃ min^-1, axial pressure60 MPa, heat preservation 8–10 min, optimum starting powders＇ ratio Al： Mg： B = 0.1915：0.1363：0.6722, and adding excessive 3 wt% Al. The abrasion resistance of Al Mg B14 composites with varying amounts of Ti B2 was studied using single-point diamond scratch tests with loads ranging from 10 to 100 N in 10 N increments. The scratch width increases almost linearly with the applied load and decreases with Ti B2 proportion increasing up to 70 wt%.With its advantages of fast heating, short reaction time,energy conservation, and high purity, this method offers a new way to synthesize Al Mg B14 and Al Mg B14–Ti B2 composites.

关键词： AIMgB_14 Field-activated and pressure-assisted synthesis Temperature Pressure Property

Progress in Seed-assisted Synthesis of (Silico) Aluminophosphate Molecular Sieves

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Chemical Research in Chinese Universities 2022年第1期38卷 1-8页

作者： ZHANG Xiaosi yang miao TIAN Peng LIU Zhongmin National Engineering Laboratory for Methanol-to-Olefins Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Aluminophosphate(AlPO)and silicoaluminophosphate(SAPO)molecular sieves are an important class of open-framework crystalline materials with wide applications thanks to their molecular-scale selectivity,moderate/strong acidity and excellent(hydro)thermal *** recent decades,the manufacturing of new microporous solids with ordered structures has been widely investigated and many effective methods have been developed,which enriches the material types and broadens their applications beyond the traditional use as catalysts and ***,the development on the synthesis of AlPO/SAPO molecular sieves is still insufficient and lags behind the needs of ***,we summarize the work on the seed-assisted synthesis of AlPO/SAPO molecular sieves compared with the zeolite synthetic system,aiming to prompt the synthesis and application of AlPO/SAPO molecular sieves.

关键词： Seed-assisted synthesis AIPO/SAPO molecular sieve Crystallization mechanism