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Nonlinear suboptimal tracking control of spacecraft approaching a tumbling target

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Chinese Physics B 2018年第9期27卷 213-222页

作者： Zhan-Peng Xu Xiao-qian che Yi-Yong Huang Yu-Zhu Bai Wen Yao College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China National Innovation Institute of Defense Technology Chinese Academy of Military ScienceBeifing 100091China

We investigate the close-range relative motion and control of a spacecraft approaching a tumbling target. Unlike the traditional rigid-body dynamics with translation and rotation about the center of mass（CM）, the kinematic coupling between translation and rotation is taken into consideration to directly describe the motion of the spacecraft＇s sensors or devices which are not coincident with the CM. Thus, a kinematically coupled 6 degrees-of-freedom（DOF） relative motion model for the instrument（feature point） is set up. To make the chaser spacecraft＇s feature point track the target＇s, an optimal tracking problem is defined and a control law with a feedback-feedforward structure is designed. With quasi-linearization of the nonlinear dynamical system, the feedforward term is computed from a specified constraint about the dynamical system and the reference model, and the feedback action is derived starting from the state-dependent Ricca equation（SDRE）. The proposed controller is compared with an existing suboptimal tracking controller, and numerical simulations are presented to illustrate the effectiveness and superiority of the proposed method.

关键词： tumbling target 6 degrees-of-freedom(DOF) relative motion suboptimal tracking control state-dependent Ricca equation(SDRE) method

Microstructure and mechanical properties of magnesium–lithium alloy prepared by friction stir processing

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Rare Metals 2021年第9期40卷 2552-2559页

作者： qian-Ying che Kuai-She Wang Wen Wang Li-Ying Huang Tian-Qi Li Xiao-Peng Xi Pai Peng Ke Qiao School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China National and Local Joint Engineering Research Center for Functional Materials Processing Xi’an 710055China School of Materials Engineering Xi’an Aeronautical UniversityXi’an 710077China

In this study, the fine-grained Mg–Li alloy was prepared by friction stir processing(FSP). The microstructure and mechanical properties of the frictionstir-processed(FSPed) Mg–Li alloy were investigated. The result showed that FSP resulted in the grain refinement, and the average grain size of the b-Li phase was about 7.5 *** the a-Mg and b-Li phases, a small amount of Li_(3)Mg_(7), Li_(2)MgAl and AlLi phases were obtained. Compared with the base metal(BM), the weakening of the crystallographic texture occurred in the FSPed material,and the c-axis of the a-phase and the crystallographic orientation of the b-phase were tilted about 45°with respect to the transverse direction(TD). The average microhardness(HV 67.8) of the stir zone was higher than that of the BM(HV 61.5). The yield strength(YS) and the ultimate tensile strength(UTS) of the FSPed material were higher than those of the BM, while the elongation slightly reduced. Grain refinement had more significant effect on strength improvement compared with the texture variation for the FSPed material. The fracture surfaces of the BM and FSPed materials showed dimple characteristics.

关键词： Magnesium-lithium alloy Friction stir processing Grain size Grain orientation Mechanical property

sea-derived fungus Acremonium ***16-126

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Synthetic and Systems Biotechnology 2021年第2期6卷 127-133页

作者： Ruonan Sun Hengyi Xu Yanyan Feng Xuewen Hou Tianjiao Zhu qian che Blaine Pfeifer Guojian Zhang Dehai Li School of Medicine and Pharmacy Ocean University of ChinaQingdao266003People’s Republic of China Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology Qingdao266237People’s Republic of China Department of chemical and Biological Engineering The State University of New York at BuffaloBuffaloNY14260United States

Acremonium species are prolific producers of therapeutic molecules which include the widely used beta-lactam antibiotic,*** light of their significant medical value,an efficient gene disruption method is required for the physiological and biochemical studies on this genus of ***,the number of selection markers that can be used for gene targeting is limited,which constrain the genetic analysis of multiple functional *** this study,we established a uridine auxotrophy based marker recycling system which achieves scarless gene deletion,and allows the use of the same selection marker in successive transformations in a deep seaderived fungus Acremonium *** identified one homologue of Acremonium chrysogenum pyrG(also as a homologous gene of the yeast URA3)from HDN16-126,designated as pyrG-A1,which can be used as a selection marker on uridine free *** then removed pyrG-A1 from HDN16-126 genome via homologous recombination(HR)on MM medium with 5-fluoroortic acid(5-FOA),a chemical that can be converted into a toxin of 5-flurouracil by pyrG-A1 activity,thus generating the HDN16-126-△pyrG mutant strain which showed auxotrophy for uridine but insensitivity to 5-FOA and enabled the use of exogenous pyrG gene as both positive and negative selection marker to achieve the scarless deletion of target DNA *** further applied this marker recycling system to successfully disrupt two target genes pepL(encodes a putative 2OG-Fe(Ⅱ)dioxygenase)and pepM(encodes a putative aldolase)identified from HDN16-126 genome,which are proposed to be functional genes related to 2-aminoisobutyric acid metabolism in *** work is the first application of uridine auxotrophy based scarless gene deletion method in Acremonium species and shows promising potential in assisting sequential genetic analysis of filamentous fungi.

关键词： Acremonium sp. Deep sea-derived Homologous recombinant Marker recycling system Markerless deletion

High-Mobility Ambipolar Benzodifurandione-Based Copolymers with Regular Donor–Acceptor Dyads Synthesized via Aldol Polycondensation

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CCS chemistry 2023年第11期5卷 2603-2616页

作者： qian che Weifeng Zhang Xuyang Wei Yankai Zhou Hao Luo Jinbei Wei Liping Wang Gui Yu Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190 School of chemical Sciences University of Chinese Academy of SciencesBeijing 100049 School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083

In this study,a family of three benzodifurandione-baseddonor–acceptor(D–A)copolymers,namelypoly[3,7-bis((E)-1-(4-octadecyldocosyl)-2-oxo-6-yl-indolin-3-ylidene)-3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dionealt-(E)-1,2-di(2,2′-bithiophen-5-yl)ethene](PBDO-DTE),poly[3,7-bis((E)-7-fluoro-1-(4-octadecyldocosyl)-2-oxo-6-yl-indolin-3-ylidene)-3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione-alt-(E)-1,2-di(2,2′-bithiophen-5-yl)ethene](PFBDO-DTE),and poly[(3E,7E)-3,7-bis(1-(4-octadecyldocosyl)-2-oxo-6-yl-1,2-dihydro-3Hpyrrolo[2,3-b]pyridin-3-ylidene)-3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione-alt-(E)-1,2-di(2,2′-bithiophen-5-yl)ethene](PNBDO-DTE),was designed and synthesized by employing aldol polycondensation reactions between benzodifurandione and bisindolin-2-ones in high *** incorporation of fluorine or sp2-hybridized nitrogen atoms on the bisindolin-2-one unit induced S…F or S…N nonbonding interactions-locked polymeric conjugated backbones for PFBDO-DTE and PNBDO-DTE,*** photoelectron spectroscopy and inverse photoemission spectroscopy measurements revealed that the two copolymers have lower frontier molecular orbitals than that of *** force microscopy and two-dimensional grazing-incidence wide-angle X-ray scattering investigations indicated the PNBDO-DTE copolymer could form more ordered molecular aggregation in the solid state than PBDO-DTE and PFBDO-DTE *** fabricated thin film transistors based on these copolymers on plastic polyethylene terephthalate substrates,and they all showed ambipolar charge transport *** them,the PNBDO-DTE-based devices afforded optimal charge transport characteristics with high hole and electron mobilities of 5.16 and 1.33cm^(2)V^(−1)s^(−1),*** study highlights that aldol polycondensation would be an extremely useful protocol in constructing high-performance polymer semiconductors.

关键词： aldol polycondensation polymer semiconductors thin filmtransistors ambipolar charge transport nonbonding interactions mobilities

Peptaibols:Diversity, bioactivity, and biosynthesis

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Engineering Microbiology 2022年第3期2卷 1-12页

作者： Xuewen Hou Ruonan Sun Yanyan Feng Runfang Zhang Tianjiao Zhu qian che Guojian Zhang Dehai Li Key Laboratory of Marine Drugs Chinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China Marine Biomedical Research Institute of Qingdao Qingdao 266101China

Peptaibols are a large family of linear,amphipathic polypeptides consisting of 5-20 amino acid residues gener-ated from the fungal nonribosomal peptide synthetase(NRPS)*** a relatively high content of non-proteinogenic amino acids such as𝛼-aminoisobutyrate(Aib)and isovaline(Iva)in the skeleton,peptaibols exhibit a wide range of biological activities,including anti-microbial,cytotoxic,and neuroleptic *** five peptai-bols brought to market for use as biocontrol agents,this class of peptides has received increasing attention from both biochemists and *** this review,we summarized the progress made in structural character-ization,elucidation of biosynthetic pathways,and investigation of biosynthesis elucidation and bioactivities,to promote further efforts to develop peptaibols as pharmaceuticals.

关键词： Peptaibols Structural diversity Bioactivity,anti-infection Biosynthesis

Penicacids E-G, three new mycophenolic acid derivatives from the marine-derived fungus Penicillium parvum HDN17-478

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Chinese Journal of Natural Medicines 2020年第11期18卷 850-854页

作者： cheN Xiao-Hui ZHOU Guo-Liang SUN Chun-Xiao ZHANG Xiao-min ZHANG Guo-Jian ZHU Tian-Jiao LI Jing che qian LI De-Hai Key Laboratory of Marine Drugs Chinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory.for Marine Drugs and Bioproducts of Qingdao Pilot National Laboratory for Marine Science and Technology Qing-dao266237China

Three new mycophenolic acid derivatives, penicacids E-G(1-3), together with three known analogues, mycophenolic acid(4), 4′-hydroxy-mycophenolic acid(5) and mycophenolic methyl ester(6), were isolated from a marine-derived fungus Penicillium parvum HDN17-478 from a South China Sea marine sediment sample. The structures of compounds 1-3 were elucidated by HRMS, NMR, and Mosher’s method. Among them, compounds 1 and 2 were the first examples of mycophenolic acid analogs with a double bond at C-3′/C-4′ position. The cytotoxicity of 1-6 was evaluated against the HCT-116, BEL-7402, MGC-803, SH-SY5 Y, HO-8910 and HL-60 cell lines, and compounds 4 and 6 showed potent cytotoxicity with IC50 values ranging from 1.69 to 12.98 μmol·L–1.

关键词： Mycophenolic acid derivatives Marine-derived fungus Penicillium parvum Cytotoxicity

Linear polyketides produced by co-culture of Penicillium crustosum and Penicillium fellutanum

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Marine Life Science & Technology 2022年第2期4卷 237-244页

作者： Guihong Yu Peng Sun Reyilamu Aierken Chunxiao Sun Zhenzhen Zhang qian che Guojian Zhang Tianjiao Zhu qianqun Gu Mingyu Li Dehai Li Key Laboratory of Marine Drugs Chinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao266003China Laboratory for Marine Drugs and Bioproducts of Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266237China Fujian Provincial Key Laboratory of Innovative Drug Target Research School of Pharmaceutical ScienceXiamen UniversityXiamen361102China School of Life Sciences Shandong Province Key Laboratory of Applied MycologyQingdao Agricultural UniversityQingdao266109China

Two new polyketides, penifellutins A (1) and B (2), possessing a 22 carbon linear skeleton, were isolated from a co-culture of the deep-sea-derived fungi Penicillium crustosum PRB-2 and Penicillium fellutanum HDN14-323. Meanwhile, two esterification products of 1, penifellutins C (3) and D (4), were obtained because compound 1 could be esterified spontaneously when stored in methanol. Their configurations were difficult to determine because of chiral central crowdedness, structural flexibility and instability. As such, we solved this issue by comprehensively using Mo2(OAc)4-based CD experiments, density functional theory calculation of 13C NMR, DP4 + probability analysis and many chemical reactions, including making acetonide derivative, Mosher’s method, PGME method, etc. Compounds 1 and 2 show obvious inhibitory activity on the liver hyperplasia of zebrafish larvae at a concentration of 10 μmol/L, while 3 and 4 show no activity, indicating that two carboxyls in the structure are important active sites.

关键词： Co-culture Polyketides Extraction and isolation Structure elucidation Antiproliferation

Development of DWDM Filter Manufacture

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光学精密工程 2001年第5期9卷 487-492页

作者： MIAO Tong qun,JIN Nan shan, ZHOU Fang che, qian Long sheng (Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130022, China) 中科院长春光学精密机械与物理所吉林长春 130022

DWDM technology is developing rapidly. Thin film narrow bandpass filter plays an important role in this field. This article presents some achievements in developing the DWDM narrow bandpass filters and also describes ... 详细信息

关键词： thin films optical coating narrow - band. filters DWDM

Effectiveness and Safety of Qishen Yiqi Dripping Pill in Patients with Acute Coronary Syndrome after Percutaneous Coronary Intervention:3-Year Results from a Multicentre Cohort Study

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Chinese Journal of Integrative Medicine 2024年第10期30卷 877-885页

作者： BAI Rui-na GU Feng che qian-zi ZHANG Xuan CAI Ya-jie XI Rui-xi ZHAO Yang GUO Ming DONG Guo-ju GAO Zhu-ye FU Chang-geng WANG Pei-li DU Jian-peng ZHANG Da-wu DUAN Wen-hui LI Li-zhi YANG Qiao-ning SHI Da-zhuo Department of Cardiovascular Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing100091China National Clinical Research Center for Chinese Medicine Cardiology Beijing100091China Department of Evidence-Based Medicine Basic Research Laboratory Institute of Basic Research in Clinical MedicineChina Academy of Chinese Medical SciencesBeijing100700China Department of Traditional Chinese Medicine Beijing Shangdi HospitalBeijing100193China National Medical Products Administration Key Laboratory for Clinical Research and Evaluation of Traditional Chinese MedicineBeijing100091China

Objectives:To evaluate the effectiveness and safety of Qishen Yiqi Dripping Pill(QSYQ)in patients with acute coronary syndrome(ACS)after percutaneous coronary intervention(PCI).Methods:This multicentre prospective cohort study was conducted at 40 centers in *** with ACS after PCI entered either the QSYQ or Western medicine(WM)groups naturally based on whether they had received QSYQ before *** group received QSYQ(0.52 g,3 times a day for 12 months)in addition to *** primary endpoint included cardiac death,non-fatal myocardial infarction,and urgent *** secondary endpoint included rehospitalization due to ACS,heart failure,stroke,and other thrombotic *** of life was assessed by the Seattle Angina Questionnaire(SAQ).Results:A total of 936 patients completed follow-up of the primary endpoint from February 2012 to December ***,487 patients received QSYQ and *** a median follow-up of 566 days(inter quartile range,IQR,517–602),the primary endpoint occurred in 46(9.45%)and 65(14.48%)patients in QSYQ and WM groups respectively[adjusted hazard ratio(HR)0.60,95%confidence interval(CI)0.41–0.90;P=0.013].The secondary endpoint occurred in 61(12.53%)and 74(16.48%)patients in QSYQ and WM groups,respectively(adjusted HR 0.76,95%CI 0.53–1.09;P=0.136).In sensitivity analysis,the results still demonstrated that WM combined with QSYQ reduced the risk of the primary endpoint(HR 0.67,95%CI 0.46–0.98;P=0.039).Moreover,QSYQ improved the disease perception domain of the SAQ(P<0.05).Conclusions:In patients with ACS after PCI,QSYQ combined with WM reduced the incidence of the primary *** findings provide a promising option for managing ACS after PCI and suggest the potential treatment for reducing the risk of primary endpoint included cardiac death,non-fatal myocardial infarction,and urgent revascularization through intermittent administration of QSYQ.(Registration *** CTR-OOC-14005552).

关键词： Qishen Yiqi Dripping Pill acute coronary syndrome percutaneous coronary intervention primary and secondary endpoint