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Design of low-energy transfer from lunar orbit to asteroid in the Sun-Earth-Moon system

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Acta Mechanica Sinica 2014年第6期30卷 966-972页

作者： Ya-min Wang Dong Qiao Ping-Yuan cui School of Aerospace Engineering Beijing Institute of Technology Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of Education

Asteroid exploration trajectories which start from a lunar orbit are investigated in this *** is assumed that the probe departs from lunar orbit and returns to the vicinity of Earth,then escapes from the Earth by performing a perigee maneuver.A low-energy transfer in Sun-EarthMoon system is ***,the feasible region of lowenergy transfer from lunar orbit to perigee within 5 000 km height above the Earth surface in Sun-Earth-Moon system is calculated and *** transfer types are found,i.e.,large maneuver and fast transfers,small maneuver and fast transfers,and disordered and slow *** of feasibility trajectories belong to the first two ***,the lowenergy trajectory leg from lunar orbit to perigee and a heliocentric trajectory leg from perigee to asteroid are patched by a perigee *** optimal full-transfer trajectory is obtained by exploiting the differential evolution ***,taking 4179 Toutatis asteroid as the target,some low-energy transfer trajectories are obtained and analyzed.

关键词： Lunar orbit Asteroid exploration Low-energy transfer Sun-Earth-Moon system

Behaviors of different inhibitors during secondary recrystallization of a grain-orientated silicon steel

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International Journal of minerals,Metallurgy and Materials 2011年第3期18卷 314-319页

作者： Feng-e cui Ping Yang Wei-min Mao School of Materials Science and Engineering University of Science and Technology Beijing 100083 China

The behaviors of different inhibitors including their composition, size, distribution, coalescence and coarsening were experimen-tally studied. It was observed that during secondary recrystallization of the tested steel, the key inhibition effect was produced by Cu2S and AlN, but not MnS. With the increase of temperature, the size distributions of AlN and Cu2S were changed to some extent. However, signifi-cant changes in particle size were not observed. The initial temperature of abnormal growth was determined by measuring the evolution of particle sizes and their distribution density during heat treatment. AlN and Cu2S are the dominant inhibitors and both are necessary, which is verified by calculating the Zener factor.

关键词： silicon steel secondary recrystallization inhibitors grain growth

Design and Synthesis of Chiral Molecular Tweezers Based on Deoxycholic Acid

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Chinese Chemical Letters 2001年第5期12卷 413-416页

作者： cui hua XUE Qi ming MU Shu hua CHEN The Faculty of chemistry Sichuan UniversityChengdu 610064

A series of new chiral molecular tweezers have been designed and synthesized by using deoxycholic acid as spacer and aromatic amines as arms. Instead of using toxic phosgene, the triphosgene was employed in synthesis of the molecular tweezers receptors. These chiral molecular tweezers showed good enantioselectivity for D-amino acid methyl esters.

关键词： Molecular tweezers synthesis deoxycholic acid recognition.

Innate immunity in tuberculosis: host defense vs pathogen evasion

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Cellular & Molecular Immunology 2017年第12期14卷 963-975页

作者： cui hua Liu Haiying Liu Baoxue Ge CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Savaid Medical School University of Chinese Academy of SciencesBeijing 101408China MOH Key Laboratory of Systems Biology of Pathogens Institute of Pathogen Biologyand Center for Tuberculosis ResearchChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100176China Shanghai Key Lab of Tuberculosis Shanghai Pulmonary HospitalTongji University School of MedicineShanghai 200433China

The major innate immune cell types involved in tuberculosis(TB)infection are macrophages,dendritic cells(DCs),neutrophils and natural killer(NK)*** immune cells recognize the TB-causing pathogen Mycobacterium tuberculosis(Mtb)through various pattern recognition receptors(PRRs),including but not limited to Toll-like receptors(TLRs),Nod-like receptors(NLRs)and C-type lectin receptors(CLRs).Upon infection by Mtb,the host orchestrates multiple signaling cascades via the PRRs to launch a variety of innate immune defense functions such as phagocytosis,autophagy,apoptosis and inflammasome *** contrast,Mtb utilizes numerous exquisite strategies to evade or circumvent host innate *** we discuss recent research on major host innate immune cells,PRR signaling,and the cellular functions involved in Mtb infection,with a specific focus on the host’s innate immune defense and Mtb immune evasion.A better understanding of the molecular mechanisms underlying host–pathogen interactions could provide a rational basis for the development of effective anti-TB therapeutics.

关键词： host–pathogen interactions immune evasion innate immune defense Mycobacterium tuberculosis tuberculosis

Spectroscopic investigation on chirality transfer in additive-driven self-assembly of block polymers

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Chinese Chemical Letters 2017年第7期28卷 1358-1364页

作者： Li-hua Pang Jing-min Li Xue-min Lu Qing-hua Lu School of Chemistry and Chemical Engineering State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

Chiral supramolecules prepared by the additive-driven self-assembly of block copolymers provide a facile method to construct helical nanostructures. In this study, we investigated the chiral transfer from chiral tartaric acid to poly（styrene）-b-poly（ethylene oxide） using small-angle X-ray scattering,transmission electron microscopy, circular dichroism, and vibrational circular dichroism. The results showed that the chirality was transferred to both the segments of block copolymer irrespective of the interaction with the chiral additives and formation of helical phase structure. However, the chirality transfer was carried out using different methods： for poly（ethylene oxide） segments, the chirality transfer was carried out via direct hydrogen bond formation; for polystyrene segments, the chirality transfer was carried out via the cooperative motion of block copolymers during the thermal annealing.

关键词： Block polymer Chirality Additive-driven Hydrogen bond Helical structure

Effect of Solvents on the Absorption Properties of GaP Nanocrystals

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Chinese Physics Letters 1998年第4期15卷 307-309页

作者： cui De-liang GAO Shan-min huaNG Bai-biao YU Shu-qin QIN Xiao-yan JIANG min-hua National Key Laboratory of Crystal Materials Institute of Crystal MaterialsShandong UniversityJinan 250100

GaP nanocrystals were synthesized by both the organic solvent reflux and high temperature high pressure benzene thermal synthesis *** effect of organic solvent on the optical absorption properties of GaP nanocrystals were *** results show that crystal grains of the sample synthesized by the latter method have better quality and *** solvents which consist of polar molecules and form strong chemical bonds with Ga atoms cause obvious redshift of the absorption spectra of GaP *** absorption spectra redshift much more if the solvent molecules have π electrons which involved in the formation of complex bond between Ga atoms and solvent molecules.

关键词： methods absorption bonds

A New 1D Iodoargentate Chain Based on Heptameric Ag7I13 Building Units Templated by Transition-metalcomplex Cation: Structure, Fluorescence and Visible Light Responding Photocatalytic Property

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1320-1328页

作者： WANG min ZHAO hua School of Science Beijing Technology and Business UniversityBeijing 100048China

Using transition-metal-complex cation as the structure-directing agent, a novel one-dimensional(1D) iodoargentate-based hybrid, namely, {[Co(2,2’-bipy)3]2(Ag7I11)·3H2O}n(1) has been synthesized and structurally characterized. The interesting 1D(Ag7I11)n4n- chain of 1 is constructed from a heptameric Ag7I13 secondary building unit, in which abundant argentophilic interactions can be observed. Intermolecular C–H···π among [Co(2,2’-bipy)3]2+ cations and C–H···I interactions between [Co(2,2’-bipy)3]2+ cations and(Ag7I11)n4n- chains contribute to the formation of a 3D network. The optical gap(2.58 eV) based on UV-Vis diffuse-reflectance measurement suggests the semiconductor nature of 1, which implies an efficient photocatalytic degradation activity on organic pollutants under visible light irradiation. As expected, 1 exhibits photocatalytic activity for the degradation of rhodamine B. The luminescence property was also studied.

关键词： organic-inorganic hybrid iodoargentate photocatalytic degradation

How to enhance the ability of mesenchymal stem cells to alleviate intervertebral disc degeneration

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World Journal of Stem Cells 2023年第11期15卷 989-998页

作者： Qing-Xiang Zhang min cui Department of Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina Department of Critical Care Medicine Wuhan Jinyintan HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430048Hubei ProvinceChina Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

Intervertebral disc(ID)degeneration(IDD)is one of the main causes of chronic low back pain,and degenerative lesions are usually caused by an imbalance between catabolic and anabolic processes in the *** environment in which the ID is located is harsh,with almost no vascular distribution within the disc,and the nutrient supply relies mainly on the diffusion of oxygen and nutrients from the blood vessels located under the *** stability of its internal environment also plays an important role in preventing *** main feature of disc degeneration is a decrease in the number of *** stem cells have been used in the treatment of disc lesions due to their ability to differentiate into nucleus pulposus cells in a nonspecific anti-inflammatory *** main purpose is to promote their *** current aim of stem cell therapy is to replace the aged and metamorphosed cells in the ID and to increase the content of the extracellular *** treatment of disc degeneration with stem cells has achieved good efficacy,and the current challenge is how to improve this ***,we reviewed current treatments for disc degeneration and summarize studies on stem cell vesicles,enhancement of therapeutic effects when stem cells are mixed with related substances,and improvements in the efficacy of stem cell therapy by adjuvants under adverse *** reviewed the new approaches and ideas for stem cell treatment of disc degeneration in order to contribute to the development of new therapeutic approaches to meet current challenges.

关键词： Mesenchymal stem cells Intervertebral disc degeneration Extracellular vesicles Nucleus pulposus cells Tissue regeneration

Optical system for extremely large spectroscopic survey telescope

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 158-174页

作者： Ding-qiang Su hua Bai Xiangyan Yuan Xiangqun cui Key Laboratory of the ministry of Education School of Astronomy and Space ScienceNanjing UniversityNanjing 210023China Nanjing Institute of Astronomical Optics and Technology(NIAOT) Chinese Academy of SciencesNanjing 210042China University of Chinese Academy of Sciences Nanjing 211135China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

This article presents research work on a spectroscopic survey *** idea is as follows:for such a telescope,a pure reflecting optical system is designed,which should have an aperture and a field of view(FOV)both as large as possible and excellent image quality,and then a strip lensm(lens-prism)atmospheric dispersion corrector(S-ADC)is added,only for correcting the atmospheric *** the fund limitation and the simplicity of scaling up,some 12-m telescopes are designed as ***,Korsch,and Meinel put forward the four-mirror Nasmyth systems I and II,which are used in this *** of 1.5°,2°,and 2.5°are *** all systems,the image qualities are *** the S-ADC relaxes the optical glass size restriction,this 12-m telescope with a FOV of 2.5°can be magnified in proportion to a 16-m *** etendue(from Frenchétendue)and focal surface will now be the largest in the *** such a telescope,a pure reflecting optical system can also be obtained.A subsequent coudésystem is designed with excellent image quality.

关键词： telescopes spectroscopic survey