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Chinese Journal of Aeronautics 2015年第2期28卷 488-498页

作者： Deng Sen Jing Bo sheng sheng Huang Yifeng Zhou Hongliang Aeronautics and Astronautics Engineering College Air Force Engineering University Unit 94371 of People's Liberation Army

Impulse components in vibration signals are important fault features of complex machines. Sparse coding （SC） algorithm has been introduced as an impulse feature extraction method, but it could not guarantee a satisfactory performance in processing vibration signals with heavy background noises. In this paper, a method based on fusion sparse coding （FSC） and online dictionary learning is proposed to extract impulses efficiently. Firstly, fusion scheme of different sparse coding algorithms is presented to ensure higher reconstruction accuracy. Then, an improved online dictionary learning method using FSC scheme is established to obtain redundant dictionary and it can capture specific features of training samples and reconstruct the sparse approximation of vibration signals. Simulation shows that this method has a good performance in solving sparse coefficients and training redundant dictionary compared with other methods. Lastly, the proposed method is further applied to processing aircraft engine rotor vibration signals. Compared with other feature extraction approaches, our method can extract impulse features accurately and efficiently from heavy noisy vibration signal, which has significant supports for machinery fault detection and diagnosis.

关键词： Dictionary learning Fault detection Impulse feature extraction Information fusion Sparse coding

Synthesis and Crystal Structure of a New Glycinato Copper Compound

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Chinese Journal of Structural Chemistry 2006年第5期25卷 631-635页

作者： XIANG sheng-Chang sheng Tian-Lu FU Rui-Biao HU sheng-Min WU Xin-Tao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A glycinato copper compound {Cu（NH2CH2COO）（H2O）ClO4} crystallizes in monoclinic, space group P21/n with a = 7.8299（9）, b = 10.3807（10）, c = 9.4775（12）A, β = 109.659（6）°, V = 725.43（12）A^3, Z = 4, Mr = 255.07, Dc = 2.335 g/cm^3, F（000） = 508,μ = 3.381 mm^-1, R = 0.0270 and wR = 0.0707 for 1677 observed reflections with Ⅰ 〉 2σ（Ⅰ）. The title compound contains a chain in the syn-anti conformation, which is generated by the glide-plane operation. The adjacent layers made up of the chains through the connection of perchlorate are related by inversion center operation, which links with each other through the hydrogen bonds.

关键词： glycinato copper complex chain hydrogen bonds

Impact of habitat diversification on arthropod communities： A study in the fields of Chinese cabbage, Brassica chinensis

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Insect Science 2007年第3期14卷 241-249页

作者： HONG-JIAO CAI ZHI-sheng LI MIN-sheng YOU Institute of Applied Ecology Research Centre for Biodiversity and Eco-Safety Fujian Agriculture and Forestry University Fuzhou China

Field trials were carried out from June to August in 2004 at Wuyishan （Wuyi Mountains）, Fujian province, China, to determine the effects of habitat diversification on arthropod communities. Two Chinese cabbage, Brassica chinensis, field 1 （F1） and field 2 （F2） surrounded by diverse vegetable cultivars were selected, while a monoculture of Chinese cabbage served as the control field （CK）. The results showed that：（i） when comparing insect abundance of each order between different habitats, significantly higher numbers of lepidopterous insects （39.76% from the each order） and lower densities of Hymenoptera （19.82%） were found in CK than in F1 and F2; （ii） compared with CK, F1 and F2 had a lower percentage of species richness and an abundance of herbivorous insects, but increased richness, abundance and biodiversity of predatory insects; （iii） no differences were observed in neutral insects＇ guild between different fields; and （iv） the dominant species for each guild depends on the habitat types and sampling dates. This study suggests that intercropping could conceivably be used in these habitats to increase the population of natural predators, thus achieving desirable and ecologically friendly results in vegetable fields.

关键词： arthropod community community composition community architecture diversity habitat

Preparation of Near IR Reflective Materials via Hollow Ballotini Enwrapped by TiO_2

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Chinese Chemical Letters 2006年第6期17卷 829-832页

作者： Cheng Yin MA Ping sheng TANG Yan sheng LI College of Chemistry and Chemical Engineering Central South University Changsha 410083

Near IR reflective functional material was made via hollow ballotini enwrapped by TiO2 according to IR reflective principles. Metatitanic acid covers on the surface of hollow ballotini through electrostatic attraction as pH is less than 2.5. The results of SEM and XRD spectrum show that TiO2 enwraps hollow ballotini well and the crystal form is anatase. When TiO2 covering thickness is below 0.5 μm, reflectance swells along with the increase of thickness, whereas above 0.5 μm it keeps stable. Coatings made from mixing enwrapped I-IB with styrene-acrylic latex were coated on aluminum foil, and reflectances were mensurated. It is found that reflectance keeps stable when the coating can wrap the base and reflectances of the coating in visible range and in near IR range are 86% and 81%, resoectively.

关键词： Titanium dioxide hollow ballotini near IR reflective material enwrap.

Lipopolysaccharide-induced Trigeminal Ganglion Nerve Fiber Damage is Associated with Autophagy Inhibition

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Current Medical Science 2023年第3期43卷 489-495页

作者： Yong LI Jing LI sheng-sheng WEI Jing DU Refractive Surgery Center Shaanxi Eye HospitalXi'an People's Hospital(Xi'an Fourth Hospital)Affiliated Guangren HospitalSchool of MedicineXi'an Jiaotong UniversityXi'an 710004China

Objective This study aimed to determine whether lipopolysaccharide(LPS)induces the loss of corneal nerve fibers in cultured trigeminal ganglion(TG)cells,and the underlying mechanism of LPS-induced TG neurite *** TG neurons were isolated from C57BL/6 mice,and the cell viability and purity were maintained for up to 7 ***,they were treated with LPS(1µg/mL)or the autophagy regulator(autophibib and rapamycin)alone or in combination for 48 h,and the length of neurites in TG cells was examined by the immunofluorescence staining of the neuron-specific proteinβ***,the molecular mechanisms by which LPS induces TG neuron damage were *** The immunofluorescence staining revealed that the average length of neurites in TG cells significantly decreased after LPS ***,LPS induced the impairment of autophagic flux in TG cells,which was evidenced by the increase in the accumulation of LC3 and p62 *** pharmacological inhibition of autophagy by autophinib dramatically reduced the length of TG ***,the rapamycin-induced activation of autophagy significantly lessened the effect of LPS on the degeneration of TG *** LPS-induced autophagy inhibition contributes to the loss of TG neurites.

关键词： lipopolysaccharide autophagy trigeminal ganglion neurons

Nitrogen-doped carbon dots as photocatalysts for organic synthesis:Effect of nitrogen content on catalytic activity

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Nano Research 2024年第6期17卷 4825-4833页

作者： Kai-Kai Niu Chao-Qun Ma Rui-Zhi Dong Hui Liu sheng-sheng Yu Ling-Bao Xing School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Regulating the doping of carbon dots(CDs)and the generation of reactive oxygen species(ROS)is essential to selectively control their application in photocatalytic organic *** study successfully synthesized five newly developed nitrogen-doped carbon dots(CDs 1-5)with varying nitrogen content,which have the ability to generate ROS when exposed to light radiation,specifically superoxide anion radicals(O_(2)•-)and singlet oxygen(^(1)O_(2)).The utilization of the aforementioned nitrogen-doped CDs as photocatalysts enables the realization of their potential in facilitating efficient photocatalytic organic ***,it was observed that the photocatalytic efficiency exhibited a gradual decrease when the nitrogen content in the CDs *** order to provide more evidence for this claim,we employed a set of five CDs in the context of photocatalytic dehalogenation ofα-bromoacetophenone,photocatalytic oxidative coupling reaction of amines to imines,photooxidation reaction of sulfides to sulfoxides,and cross-dehydrogenation coupling(CDC)reaction,in which it was further observed that there was a steady decrease in the yields of photocatalytic organic reactions as the nitrogen content in CDs ***,CDs 1 exhibited the best photocatalytic efficiency,thereby reinforcing the hypothesis that a higher nitrogen content corresponds to a decreased catalytic *** study not only investigates the impact of the nitrogen content on the catalytic performance of CDs,but also offers valuable insights for the future utilization of CDs for photocatalytic organic reactions in water.

关键词： carbon dots nitrogen-doped reactive oxygen species photocatalysis

A Network-Attached Storage System Supporting Guaranteed QoS

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Wuhan University Journal of Natural Sciences 2005年第5期10卷 838-842页

作者： KONG Hua-feng YU sheng-sheng LU Hong-wei School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 Hubei China

We propose a network-attached storage system that can support guaranteed Quality of Service （QoS）, called POPNet Storage. The special policy of date access and disk scheduling is enable users to access files quickly and directly with guaranteed QoS in the POPNet Storage. The POPNet Storage implements a measurement-based admission control algorithm （PSMBAC） to determine whether to admit a new data access request stream and admit as many requests as possible while meeting the QoS guarantees to its clients. The data reconstruction algorithms in the POPNet Storage also put more emphasis on data availability and guaranteed QoS, thus it is designed to complete the data recovery as soon as possible and at the same time provide the guaranteed QoS for high-priority data access. The experiment results show that the POPNet Storage can provide more significant performance, reliability, and guaranteed QoS than conventional storage systems.

关键词： network-attached storage storage system QoS disk scheduling admission control

Synthesis and Fungicidal Activities of 2-Alkylthio-5-(3,4,5-tribenzyloxyphenyl)-1,3,4-oxadiazoles

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Chinese Chemical Letters 2006年第11期17卷 1427-1430页

作者： De Qing LONG De Jiang LI Wei Quan CAI sheng sheng CHEN Department of Chemistry Yunyang Teachers College Hubei 442700 College of Chemical Engineering Wuhan University of Technology Wuhan 430070

Abstract： Ten novel 2-alkylthio-5-（3, 4, 5-tribenzyloxyphenyl）-1, 3, 4-oxadiazole derivatives （5a-j） were synthesized from methyl 3, 4, 5-trihydroxybenzoate by ethedfication, hydrazidation, cyclization and thioetherification reactions. The structures of 5a-j were confirmed by 1HNMR, MS spectra and elemental analysis. The results indicated that most of the compounds 5 exhibited good fungicidal activities. The activity of 5h is higher than 90% against Fusarium oxysporum and Botrytis cinereapers in 50 mg/L.

关键词： 1,3,4-Oxadiazole derivatives synthesis fungicidal activity.

Crevice Corrosion Performance of 436 Ferritic Stainless Steel Studied by Different Electrochemical Techniques in Sodium Chloride Solutions with Sulfate Addition

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 815-822页

作者： Jia-Ming Wang sheng-sheng Qian Yuan-Yuan Liu Yang-Ting Sun Yi-Ming Jiang Jin Li Department of Materials Science Fudan University

The crevice corrosion behaviors of 436 stainless steels in chloride-containing solutions with sulfate addition were studied using potentiodynamic, galvanostatic and repassivation potential measurements. The results of these electrochemical tests were compared and discussed. Galvanostatic test was proved to be the most powerful technique in detecting the crevice corrosion of 436 stainless steels, while the repassivation potential measurement was the most time-saving method in this study. Sulfate ions have inhibited the crevice corrosion of 436 stainless steels in chloride-containing solution, which may result from the effects of competitive adsorption and the IR drop mechanism.

关键词： Crevice corrosion Ferritic stainless steels Electrochemical techniques Sulfate ions Competitive adsorption IR drop mechanism

Design and screening of antisense oligodeoxynucleotides against PAI-1 mRNA in endothelial cells in vitro

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Acta Pharmacologica Sinica 2006年第8期27卷 1018-1023页

作者： Qi-sheng JIANG sheng-qi WANG~2 Beijing Institute of Radiation Medicine,Beijing 100850,China Beijing Institute of Radiation Medicine Beijing China

Aim:To design and screen antisense oligodeoxynucleotides(ASODNs),whichinhibit type-1 plasminogen activator inhibitor(PAI-1)expression in human umbili-cal vein endothelial cells(HUVEC)in ***:Twenty seven ASODNsagainst different sites of PAI-1 mRNA were designed and transfected to HUVECby lipofectin in *** effects of ASODNs on PAI-1 antigen,PAI-1 activityand PAI-1 mRNA expression were detected by ELISA,amidolytical assay and RT-PCR,***:Transforming growth factor β1(TGF-β1)-treatedHUVEC increased the expression of PAI-1 compared with the normal *** among twenty seven designed ASODNs were effective in inhibiting the in-crease in PAI-1 antigen and PAI-1 activity in a dose-dependent manner after *** particular,ASODN 14(AO14)exhibited the best inhibitory *** control sequences of AO14,including sense,scramble,and mismatchsequences,did not significantly inhibit PAI-1 *** was revealed that theinhibitory efficacy of AO14 was in a sequence-specific ***-PCR showedthat ASODN 1,7,8,14,and 15 decreased PAI-1 mRNA expression induced byTGF-β1and AO14 showed the best inhibitory ***:ASODN 1,7,8,14,and 15,among twenty seven designed ASODNs against PAI-1 mRNA,signifi-cantly decreased PAI-1 antigen and PAI-1 activity induced by TGF-β1x in a dose-dependent manner in HUVEC in ***14 showed the best inhibitory effect onPAl-1 expression in a sequence-specific *** results of RT-PCR indicatedthat inhibitory effects of ASODNs on PAI-1 biosynthesis occurred at the *** among five effective target sites of ASODNs located at the translationinitiation Site or within the translation area of PAI-1 mRNA,suggesting that thesesites may be promising sites for the design of effective ASODNs.

关键词： plasminogen activator inhibitor 1 antisense oligodeoxynucleotide endothelial cells