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Changing law of launching pitching angular velocity of rotating missile

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Chinese Journal of Aeronautics 2014年第5期27卷 1171-1179页

作者： Liu guang Xu Bin Jiao Xiaojuan zhen Tiesheng Department of Mechanics and Engineering Science Fudan University Shanghai Electro-Mechanical Engineering Institute

In order to provide accurate launching pitching angular velocity（LPAV） for the exterior trajectory optimization design, multi-flexible body dynamics（MFBD） technology is presented to study the changing law of LPAV of the rotating missile based on spiral guideway. An MFBD virtual prototype model of the rotating missile launching system is built using multi-body dynamics modeling technology based on the built flexible body models of key components and the special force *** built model is verified with the frequency spectrum analysis. With the flexible body contact theory and nonlinear theory of MFBD technology, the research is conducted on the influence of a series of factors on LPAV, such as launching angle change, clearance between launching canister and missile,thrust change, thrust eccentricity and mass eccentricity, etc. Through this research, some useful values of the key design parameters which are difficult to be measured in physical tests are obtained. Finally,a simplified mathematical model of the changing law of LPAV is presented through fitting virtual test results using the linear regression method and verified by physical flight tests. The research results have important significance for the exterior trajectory optimization design.

关键词： LPAV MFBD Modeling Rotating missile Simulation Virtual prototyping

Discrepancy between non-invasive prenatal testing result and fetal karyotype caused by rare confined placental mosaicism: A case report

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World Journal of Clinical Cases 2022年第24期10卷 8641-8647页

作者： zhen Li guang-Rui Lai Department of Obstetrics and Gynecology Shengjing Hospital of China Medical UniversityShenyang 110004Liaoning ProvinceChina Department of Clinical Genetics Shengjing Hospital of China Medical UniversityShenyang 110004Liaoning ProvinceChina

BACKGROUND Confined placental mosaicism(CPM)is one of the major reasons for discrepancies between the results of non-invasive prenatal testing(NIPT)and fetal karyotype *** SUMMARY We encountered a primiparous singleton pregnant woman with a rare CPM consisting of 47,XY,+21;47,XXY;and 46,XY,who obtained a false-positive result on NIPT with a high risk for trisomy ***-number variation sequencing on amniotic fluid cells,fetal tissue,and placental biopsies showed that the fetal karyotype was 47,XXY,while the placenta was a rare mosaic of 47,XY,+21;47,XXY;and 46,*** The patient had a rare CPM consisting of 47,XY,+21;47,XXY;and 46,XY,which caused a discrepancy between the result of NIPT and the actual fetal *** is important to remember that NIPT is a screening test,not a diagnostic *** positive result should be confirmed with invasive testing,and routine ultrasound examination is still necessary after a negative result.

关键词： Non-invasive prenatal testing Confined placental mosaicism Copy-number variation sequencing Karyotype analysis Case report

Aerodynamic actuation characteristics of radio-frequency discharge plasma and control of supersonic flow

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Chinese Physics B 2019年第2期28卷 321-330页

作者： zhen Yang Hui-Min Song Hong-Yu Wang Shan-guang Guo Min Jia kang Wang Science and Technology on Plasma Dynamics Laboratory Air Force Engineering University

In this paper, aerodynamic actuation characteristics of radio-frequency(RF) discharge plasma are studied and a method is proposed for shock wave control based on RF discharge. Under the static condition, a RF diffuse glow discharge can be observed; under the supersonic inflow, the plasma is blown downstream but remains continuous and ***-resolved schlieren is used for flow field visualization. It is found that RF discharge not only leads to continuous energy deposition on the electrode surface but also induces a compression wave. Under the supersonic inflow condition, a weak oblique shock wave is induced by discharge. Experimental results of the shock wave control indicate that the applied actuation can disperse the bottom structure of the ramp-induced oblique shock wave, which is also observed in the extracted shock wave structure after image processing. More importantly, this control effect can be maintained steadily due to the continuous high-frequency(MHz) discharge. Finally, correlations for schlieren images and numerical simulations are employed to further explore the flow control mechanism. It is observed that the vortex in the boundary layer increases after the application of actuation, meaning that the boundary layer in the downstream of the actuation position is thickened. This is equivalent to covering a layer of low-density smooth wall around the compression corner and on the ramp surface, thereby weakening the compressibility at the compression corner. Our results demonstrate the ability of RF plasma aerodynamic actuation to control the supersonic airflow.

关键词： radio-frequency(RF) discharge plasma surface discharge flow control aerodynamic actuation

Buqi-Tongluo Decoction inhibits osteoclastogenesis and alleviates bone loss in ovariectomized rats by attenuating NFATc1, MAPK, NF-κB signaling

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Chinese Journal of Natural Medicines 2025年第1期23卷 90-101页

作者： Yongxian Li Jinbo Yuan Wei Deng Haishan Li Yuewei Lin Jiamin Yang Kai Chen Heng Qiu Ziyi Wang Vincent Kuek Dongping Wang zhen Zhang Bin Mai Yang Shao Pan kang Qiuli Qin Jinglan Li Huizhi Guo Yanhuai Ma Danqing Guo Guoye Mo Yijing Fang Renxiang Tan Chenguang Zhan Teng Liu Guoning Gu Kai Yuan Yongchao Tang De Liang Liangliang Xu Jiake Xu Shuncong Zhang The First Clinical Academy Guangzhou University of Chinese Medicine The First Affiliated Hospital of guangzhou University of Chinese Medicine Lingnan Medical Research Center of guangzhou University of Chinese Medicine School of Biomedical Sciences University of Western Australia Curtin Medical School Curtin University Foshan Hospital of Traditional Chinese Medicine School of Public Health and Management Guangzhou University of Chinese Medicine The State Key Laboratory of Pharmaceutical Biotechnology Institute of Functional Biomolecules Nanjing University

Osteoporosis is a prevalent skeletal condition characterized by reduced bone mass and strength, leading to increased fragility. Buqi-Tongluo(BQTL) decoction, a traditional Chinese medicine(TCM) prescription, has yet to be fully evaluated for its potential in treating bone diseases such as osteoporosis. To investigate the mechanism by which BQTL decoction inhibits osteoclast differentiation in vitro and validate these findings through in vivo *** employed MTS assays to assess the potential proliferative or toxic effects of BQTL on bone marrow macrophages(BMMs) at various concentrations. TRAc P experiments were conducted to examine BQTL's impact on osteoclast differentiation. RT-PCR and Western blot analyses were utilized to evaluate the relative expression levels of osteoclast-specific genes and proteins under BQTL stimulation. Finally, in vivo experiments were performed using an osteoporosis model to further validate the in vitro findings. This study revealed that BQTL suppressed receptor activator of NF-κB ligand(RANKL)-induced osteoclastogenesis and osteoclast resorption activity in vitro in a dose-dependent manner without observable *** inhibitory effects of BQTL on osteoclast formation and function were attributed to the downregulation of NFATc1 and c-fos activity, primarily through attenuation of the MAPK, NF-κB, and Calcineurin signaling pathways. BQTL's inhibitory capacity was further examined in vivo using an ovariectomized(OVX) rat model, demonstrating a strong protective effect against bone loss. BQTL may serve as an effective therapeutic TCM for the treatment of postmenopausal osteoporosis and the alleviation of bone loss induced by estrogen deficiency and related conditions.

关键词： Buqi-Tongluo Estrogen deficiency MAPK NF-κB NFATc1 Osteoclast Osteoporosis

Effect of temperature and mating pair on tribological properties of DLC and GLC coatings under high pressure lubricated by MoDTC and ZDDP

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Friction 2021年第6期9卷 1390-1405页

作者： kang LIU Jia-jie kang guang-an ZHANG Zhi-bin LU Wen YUE School of Engineering and Technology China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Deep GeoDrilling Technology of Ministry of Natural Resources Beijing 100083China zhengzhou Institute China University of Geosciences(Beijing)Zhengzhou 451283China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Diamond-like carbon(DLC)and graphite-like carbon(GLC)coatings have good prospects for improving the surface properties of engine ***,further understanding is needed on the effect of working conditions on tribological *** this study,GLC and two types of DLC coatings were deposited on GCr15 substrate for *** friction and wear properties of self-mated and steel-mated pairs were *** temperatures(25 and 90℃),three lubrication conditions(base oil,molybdenum dithiocarbamate(MoDTC)-containing oil,MoDTC+zinc dialkyldithiophosphate(ZDDP)-containing oil),and high Hertz contact stress(2.41 GPa)were applied in the *** results showed that high temperature promoted the effect of ZDDP on steel-mated pairs,but increased wear under base oil *** increased wear for steel-mated pairs lubricated by MoDTC-containing oil was due to abrasive wear probably caused by MoO_(3) andβ-FeMoO_(4).It was also found that in most cases,the tribological properties of self-mated pairs were better than those of steel-mated pairs.

关键词： diamond-like carbon(DLC) graphite-like carbon(GLC) mating pair temperature oil additives

A facile synthesis of magnetite single-crystal particles by employing GO sheets as template for promising application in magnetic fluid

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Rare Metals 2019年第8期38卷 764-769页

作者： zhen Qin zhen-Hui Ma Jian-kang Zhi Yong-Ling Fu School of Mechanical Engineering and Automation Beihang University Beijing 100083China College of Materials Science and Engineering Beijing University of Technology Beijing 100124China

It was reported a facile strategy to fabricate magnetite(Fe3O4)single-crystal particles with critical single-domain size by employing graphene oxide(GO)sheets as *** this method,the small-sized Fe2 O3 nanoparticles were first synthesized,and then low-temperature annealing under H2 would convert them into large-sized Fe3 O4 single-crystal *** synthetic particles with an average size of 100 nm exhibit high saturation magnetization(Ms)of 0.085 A·m^2·g^-1,which is very close to theoretical value,being among the highest values in ever reported for Fe3O4 made from chemical *** this basis,the small-sized Fe3 O4 particles(average size of 30 nm)were also fabricated by coating with Na2 CO3 shell.

关键词： Fe3O4 Critical single-domain size Saturation magnetization Chemical synthesis

A phenylphenthiazide anchored Tb（Ⅲ）-cyclen complex for fluorescent turn-on sensing of ClO-

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Chinese Chemical Letters 2025年第2期 297-301页

作者： Ya-Ping Liu Zhi-Rong Gui zhen-Wen Zhang Sai-kang Wang Wei Lang Yanzhu Liu Qian-Yong Cao School of Chemistry and Chemical Engineering Nanchang University

A phenylphenothiazine anchored Tb（Ⅲ）-cyclen complex PTP-Cy-Tb for hypochlorite ion（ClO-） detection has been designed and prepared. PTP-Cy-Tb shows a weak Tb-based emission with AIE-characteristics in aqueous solutions. After addition of ClO-, the fluorescence of PTP-Cy-Tb gives a large enhancement for oxidization the thioether to sulfoxide group. The detection limit of PTP-Cy-Tb toward ClO-is as low as 8.85 nmol/L. The sensing mechanism was detailedly investigated by time of flight mass spectrometer（TOF-MS）, Fourier transform infrared spectroscopy（FT-IR） and density functional theory（DFT） *** addition, PTP-Cy-Tb has been successfully used for on-site and real-time detection of ClO-in real water samples by using the smartphone-based visualization method and test strips.

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Two Coordination Polymers Containing Linear Co(Ⅱ)-Trinuclear and Cu(Ⅱ)-Chain Assembled from 4-Fluorocinnamic Acid and N-Donor Ligand

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Chinese Journal of Structural Chemistry 2016年第2期35卷 286-292页

作者： kang Hai-Xia FU Yu-Qin XIN Ling-Yun LI Gui-Lian MA Lu-Fang LIU guang-zhen College of Chemistry and Chemical Engineering Luoyang Normal University

Two new coordination polymers,named {[Co3（pfca）6（phen）2]·2H2O}n（1） and[Cu（pfca）2（4,4＇-bpy）（H2O）]n（2）（Hpfca = 4-fluorocinnamic acid and 4,4-bpy = 4,4-bipyridine）,were hydrothermally synthesized and characterized by elemental analysis,IR spectroscopy,thermogravimetric analysis（TGA）,and single-crystal X-ray *** 1 crystallizes in the triclinic crystal system,space group P1 with a = 10.939（3）,b = 12.430（4）,c = 13.815（4） A,α=78.436（3）,β= 70.261（3）,γ= 80.268（3）°,V= 1721.8（9） A^3,Dc = 1.508 g/cm^3,Mr= 1564.06,Z = 1,F（000） = 799,μ= 0.802 mm^（-1）,the final R = 0.0432 and wR = 0.1015 for 13250 observed reflections with I 2σ（I）.Complex 2 is of monoclinic system,space group P2／lc with a =15.4985（14）,b = 15.8424（14）,c = 10.9528（10） A,β= 107.1600（10）°,V= 2569.6（4） A^3,Dc = 1.468g/cm^3,Mr = 568.02,Z = 4,F（000） = 1164,μ= 0.906 mm^（-1）,the final R = 0.0371 and wR = 0.0842 for 18183 observed reflections with I〉 2σ（I）.Complex 1 features linear Co（Ⅱ）-trinuclear units,which are assembled into a final 3D supramolecular structure through π…π stacking interactions and F-H weak *** 2 consists of 1D polymeric Cu（Ⅱ）-chains that are further cohered together by extensive H-bonds.

关键词： 4-fluorocinnamic acid coordination polymers trinuclear chainmagnetic property

Integrated Entry Guidance for Reusable Launch Vehicle

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Chinese Journal of Aeronautics 2007年第1期20卷 1-8页

作者： NING Guo-dong ZHANG Shu-guang FANG zhen-ping School of Aeronautical Science and Technology Beijing University of Aeronautics and Astronautics Beijing 100083 China

A method for the implementation of integrated three-degree-of-freedom constrained entry guidance for reusable launch vehicle is presented. Given any feasible entry conditions, terminal area energy management interface conditions, and the reference trajectory generated onboard then, the method can generate a longitudinal guidance profile rapidly, featuring linear quadratic regular method and a proportional-integral-derivative tracking law with time-varying gains, which satisfies all the entry corridor constraints and meets the requirements with high precision. Afterwards, by utilizing special features of crossrange parameter, establishing bank-reversal corridor, and determining bank-reversals according to dynamically adjusted method, the algorithm enables the lateral entry guidance system to fly a wide range of missions and provides reliable and good performance in the presence of significant aerodynamic modeling uncertainty. Fast trajectory guidance profiles and simulations with a reusable launch vehicle model for various missions and aerodynamic uncertainties are presented to demonstrate the capacity and reliability of this method.

关键词： guidance trajectory generation entry onboard constraint robustness