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Rectangular optical filter based on high-order silicon microring resonators

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Optoelectronics Letters 2017年第4期13卷 268-270页

作者： bao Jia-qi YU Kan WANG Li-jun YIN juan-juan Department of lnformation Science and Technology Wenhua College Wuhan 430074 China

The rectangular optical filter is one of the most important optical switching components in the dense wavelength divi- sion multiplexing （DWDM） fiber-optic communication system and the intelligent optical network. The integrated high- order silicon microring resonator （MRR） is one of the best candidates to achieve rectangular filtering spectrum re- sponse. In general, the spectrum response rectangular degree of the single MRR is very low, so it cannot be used in the DWDM system. Using the high-order MRRs, the bandwidth of flat-top pass band, the out-of-band rejection degree and the roll-off coefficient of the edge will be improved obviously. In this paper, a rectangular optical filter based on high- order MRRs with uniform couplers is presented and demonstrated. Using 15 coupled race-track MRRs with 10 pm in radius, the 3 dB flat-top pass band of 2 nm, the out-of-band rejection ratio of 30 dB and the rising and falling edges of 48 dB/nm can be realized successfully.

关键词： Bandpass filters Dense wavelength division multiplexing Optical communication Optical filters Optical resonators Resonators

Numerical Investigation on Dynamic Characteristics of Casing Deformation During Marine Hydrate Production

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China Ocean Engineering 2022年第4期36卷 638-648页

作者： CHANG Yuan-jiang WANG kang CHEN Guo-ming SUN bao-jiang SUN Huan-zhao JI Miao-miao Centre for Offshore Engineering and Safety Technology(COEST) China University of Petroleum(East China)Qingdao 266580China College of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China

Formation subsidence is inevitable during marine hydrate decomposition,and the consequent casing deformation seriously threatens the security of sustainable hydrate *** to insufficient observed data of formation subsidence in field,displacement boundary condition of casing is *** the conventional static methods are inapplicable for the calculation of casing deformation in hydrate production *** present work aims at proposing an approach to investigate dynamic deformation of the casing during hydrate *** the proposed methodology,based on the movement theory of hydrate decomposition front,hydrate decomposition process can be simulated,in which hydrate reservoir strength formation subsidence showed time-dependent *** considering the actual interactions among casing,cement and formation,three models of hydrate production well are developed to reveal the static and dynamic deformation mechanisms of the *** application of the proposed methodology is demonstrated through a case *** show that buckling deformation and bending deformation of casing reduce the passing ability of downhole tools in deformed casing by 4.2%and 7.5%,*** the progress of hydrate production,buckling deformation will increase obviously,while a little increase of bending deformation will occur,as the formation slippage induced by formation inclination is much larger than that caused by hydrate *** proposed approach can provide theoretical reference for improving casing integrity of marine hydrate production.

关键词： hydrate production casing deformation dynamic characteristics formation inclination

FBXW7 regulates epithelial barrier impairment in human bronchial epithelial cells in vitro by targeting apoptosis signal-regulating kinase1 via the p38 pathway

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BIOCELL 2021年第3期45卷 723-731页

作者： JINGRONG SONG juan kang WEI LV YAN DONG XIAOYING ZHANG Department of Pediatrics Shanghai Ninth People’s HospitalShanghai Jiaotong University School of MedicineShanghai200011China

Bronchial asthma is a common chronic inflammatory disease characterized by airway hyperresponsiveness(AHR),inflammatory cell infiltration,and airway remodeling.F-box/WD repeat-containing protein 7(FBXW7),an E3 ubiquitin ligase,is required for various endothelial functions,such as cell migration,inflammation,and endothelial *** study aimed to investigate the role of FBXW7 in lipopolysaccharide(LPS)-induced epithelial barrier impairment in bronchial epithelial cells in *** using lentivirus-based technology,FBXW7 was overexpressed or silenced(24 h)in human bronchial epithelial(16HBE)cells,which were treated with LPS or not(24 h).Immunoprecipitation(IP)detection and Western blot analysis were used to evaluate the interaction of target *** permeability was measured using transepithelial electrical resistance and FITC dextran flux(48 h).IL-1β,IL-18 and TNF-αin cell supernatants were measured using ELISA(48 h).The results showed that LPS stimulation suppressed FBXW7 expression in a time-and dose-dependent *** exposure decreased cell proliferation,elevated IL-1β,IL-18 and TNF-α,increased epithelial permeability,and p38 *** LPS-induced changes were partly compromised by FBXW7 *** to LPS stimulation,FBXW7 knockdown increased epithelial permeability and levels of inflammatory cytokines and p38 phosphorylation,which were,in part,blocked by apoptosis signal-regulating kinase(ASK)1 knockdown or p38 pathway *** and Western blot analysis showed that FBXW7 interacted with ***1 expression was inversely associated with FBXW7 ***7 overexpression markedly enhanced ASK1 *** data revealed that FBXW7 counter against inflammation and protects epithelial barrier integrity in bronchial epithelial cells by promoting ubiquitination-mediated degradation of ASK1 via the p38 pathway.

关键词： Bronchial epithelial cells Inflammation Lipopolysaccharide Transepithelial electrical resistance FITC dextran flux

Triterpenoids from Uncaria rhynchophylla and Their PTP1B Inhibitory Activity

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Phyton-International Journal of Experimental Botany 2022年第8期91卷 1809-1816页

作者： Shuaibin Luo Xuemei Zhang kang He juan Zou Chang-An Geng Guizhou University of Traditional Chinese Medicine Guiyang550025China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesYunnan Key Laboratory of Natural Medicinal ChemistryKunming650201China

Uncaria rhynchophylla(Gouteng)is a famous traditional Chinese medicine used for psychiatric and hypotensive purposes in *** this study,the ethyl acetate(EtOAc)part of *** was revealed with protein tyrosine phosphatase 1B(PTP1B)inhibitory *** investigation on the EtOAc part yielded one new triterpenoid,3β-formyloxy-6β,19α-dihydroxyurs-12-en-28-oic acid(1)and four known ones,3β,6β,19α-trihydroxyurs-12-en-28-oic acid(2),2-oxopomolic acid(3),3β,19α-dihydroxy-6-oxo-olean-12-en-28-oic acid(4)and sumaresinolic acid(5).The structure of compound 1 was determined by extensive HRESIMS,IR,1D and 2D NMR spectroscopic *** ursane-type triterpenoids(2 and 3)showed selective inhibition on PTP1B with IC50 values of 48.2 and 178.7μ*** enzyme kinetic study suggested that compounds 2 and 3 were mixtype inhibitors on PTP1B with Ki values of 15.6 and 132.5μ*** investigation manifests the antidiabetic potency of *** with triterpenoids as the active constituents.

关键词： Uncaria rhynchophylla triterpenoids antidiabetic effects PTP1B inhibitors

Chiral Recognition and Photoreaction of β-Amino Acids with Iridium(III)Complexes

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Chinese Journal of Chemistry 2022年第24期40卷 2909-2918页

作者： Ming-Feng Xiong Hai-Yun Zhou Xiao-kang Huang Jing-Yan Fan bao-Hui Ye MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen UniversityGuangzhouGuangdong510275 China Instrumental Analysis and Research Center Sun Yat-sen UniversityGuangzhouGuangdong510275 China

β-Amino acids(AAs),homologs ofα-AAs,are important building blocks of biological ***,chiral recognitions ofβ-AAs with Ir(III)complexes are reported,in favor of formation of the thermodynamically stableΛ-[Ir(pq)_(2)(D-β-AAs)]andΔ-[Ir(pq)_(2)(L-β-AAs)](pq is 2-phenylquinoline)*** photoreactions of[Ir(pq)_(2)(β-AA)]complexes are observed in an EtOH solution in the presence of O_(2) at room *** primaryβ-AAs complexes,such as rac-[Ir(pq)_(2)(β-ala)](β-ala isβ-alanine),Δ-[Ir(pq)_(2)(D-β-ma)]andΛ-[Ir(pq)_(2)(D-β-ma)](β-ma isβ-methylalanine),Δ-[Ir(pq)_(2)(D-β-pa)]andΛ-[Ir(pq)_(2)(D-β-pa)](β-pa isβ-phenylalanine),and rac-[Ir(pq)_(2)(β-dma)](β-dma is 3,3-dimethyl-β-alanine),are interligand C—N cross-coupling in situ between pq andβ-AAs *** secondaryβ-AA complexesΔ-[Ir(pq)_(2)(L-β-pro)]andΛ-[Ir(pq)_(2)(L-β-pro)](β-pro isβ-proline,2-(pyrrolidin-2-yl)acetic acid)are dehydrogenatively oxidized into imino acid complexesΔ-[Ir(pq)_(2)(L-β-pro-2H^(β)’)]andΛ-[Ir(pq)_(2)(L-β-pro-2H^(β)’)](L-β-pro-2H^(β)’=2-(3,4-dihydro-2H-pyrrol-2-yl)acetic acid),***,the dehydrogenative reaction inΔ-[Ir(pq)_(2)(L-β-pro)]diastereomer is regioselective depending on the reaction temperature,affordingΔ-[Ir(pq)_(2)(L-β-pro-2H^(β)’)]andΔ-[Ir(pq)_(2)(L-β-pro-2H^(β))](β-pro-2H^(β)=2-(3,4-dihydro-2H-pyrrol-5-yl)acetic acid)at low *** chiral recognitions and photoreactions of Ir(III)-β-AAs complexes are much different from the previous observations in Ir(III)-α-AAs complexes.

关键词： Photooxidation Chiral recognition Regioselectivity Enantioselectivity β-Amino acid

Cloning and structural characterization of juvenile hormone diol kinase in Spodoptera litura

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Insect Science 2016年第6期23卷 819-828页

作者： bao-juan Zeng Yuan Lv Li-Li Zhang Li-Hua Huang Qi-Li Feng Guangzhou Key Laboratory of Insect Development Regulation and Application Research School of Life Sciences South China Normal University Guangzhou 510631 China

Juvenile hormone （JH） is one of the key insect hormones that regulate metamorphosis. Juvenile hormone diol kinase （JHDK） is an enzyme involved in JH metabolism and catalyzes JH diol to form a polar end product, JH diol phosphate that has no JH activity. In this study, a JHDK complementary DNA （cDNA） was cloned from Spodoptera litura and the structure and expression of the gene was characterized. The cDNA was 714 base pairs in length and encoded a protein of 183 amino acids with a molecular mass of 21 kDa and an isoelectric point of 4.55. Based on the structure, three putative calcium binding motifs and guanosine triphosphate-binding motifs were predicted in the protein. Modeling of the 3-D structure showed that the protein consisted of eight α-helixes linked with loops, with no β-sheets. The gene was expressed in the epidermis, fat body and midgut of fifth and sixth instar larvae. The expression level in the epidermis was lower than in the fat body and midgut. The gene was expressed at higher levels at the early stages than in the later stages of fifth and sixth instar midgut and fat body. The results suggest that this gene may be involved in the regulation of the JH titer in larvae ofS. litura.

关键词： juvenile hormone juvenile hormone diol kinase metabolism Spodoptera litura

Influence of metallurgical processing parameters on defects in cold-rolled steel sheet caused by inclusions

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International Journal of Minerals,Metallurgy and Materials 2019年第4期26卷 440-446页

作者： Rui Wang Yan-ping bao Yi-hong Li Zhi-jie Yan Da-zhao Li Yan kang School of Materials Science and Engineering North University of China State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Materials Science and Engineering Taiyuan University of Science and Technology

The cleanliness and defects for cold-rolled steel sheet caused by inclusions are greatly influenced by parameters in the metallurgical processing. Good control of parameters during the processing can lead to a better product. In this paper, data mining was used to explore the influence of parameters on defects in steel sheets. A decision tree model was established and it was found that the oxygen content before deoxidation, the end-point temperature of the converter, and the temperature before deoxidation had a great impact on the defects in the cold-rolled sheet that were caused by inclusions. This finding was confirmed by experiments with infrared absorption, scanning electron microscopy(SEM), energy dispersive X-ray spectroscopy(EDS), and automatic inclusion analysis methods. After optimization according to results from the model and experiments, the defect rate caused by the inclusions was reduced from 0.92% to 0.38%.

关键词： IF steel steel cleanliness data mining inclusions

Preparation of new hybrid organic/inorganic polymeric chiral stationary phases for ligand-exchange chromatography

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Chinese Chemical Letters 2007年第10期18卷 1250-1252页

作者： Rui juan Song Yu Fu Na Yao Yuan De Long Tian bao Huang Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Three new hybrid organic/inorganic polymeric ligand-exchange chiral stationary phases were developed by radical chain transfer reaction and surface grafting on silica gel, and successfully used for the enantioseparations of DL-amino acids and DL-hydroxyl adds. The resolutions were achieved by using water containing 2.0 × 10^-4 mol/L of CuAc2 as a mobile phase, column temperature of 40 ℃, flow rate of 1.0 mL/min and detection at UV 254 nm. The elution order of D-isomer before L-isomer was observed for all DL-amino acids resolved except DL-Pro.

关键词： Chiral stationary phase Ligand-exchange chromatography DL-Hydroxyl acid Surface grafting DL-Amino acid

Facile and Large-scale Fabrication of Self-crimping Elastic Fibers for Large Strain Sensors

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Chinese Journal of Polymer Science 2021年第7期39卷 914-924页

作者： Jin-Chao Yu kang Chen Hong Ji Yang Zhang Yu-Mei Zhang Zhi-juan Pan College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

Stretchable conductive fibers offer unparalleled advantages in the development of wearable strain sensors for smart textiles due to their excellent flexibility and ***,the practical applications of these fibers in wearable devices are hindered by either contradictory properties of conductive fibers(high stretchability versus high sensing stability),or lack of manufacturing ***,we present a facile approach for highly stretchable self-crimping fiber strain sensors based on a polyether-ester(TPEE)elastomer matrix using a side-by-side bicomponent melt-spinning process involving two parallel but attached components with different shrinkage *** TPEE component serves as a highly elastic mechanical support layer within the bicomponent fibers,while the conductive component(E-TPEE)of carbon black(CB),multiwalled carbon nanotubes(MWCNTs)and TPEE works as a strain-sensitive *** addition to the intrinsic elasticity of the matrix,theTPEE/E-TPEE bicomponent fibers present an excellent form of elasticity due to *** self-crimping elongation of the fibers can provide a large deformation,and after the crimp disappears,the intrinsic elastic deformation is responsible for monitoring the strain *** reliable strain sensing range of theTPEE/E-TPEE composite fibers was 160%-270%and could be regulated by adjusting the crimp *** importantly,the TPEE/E-TPEE fibers had a diameter of 30-40 pm and tenacity of 40-50 MPa,showing the necessary *** work introduces new possibilities for fiber strain sensors produced in standard industrial spinning machines.

关键词： Conductive polyether-ester elastic fiber Side-by-side bicomponent fiber Self-crimping Strain sensing